|
P067 |
DIAGNOSIS OF STENOSES OF THE PROXIMAL
VERTEBRAL ARTERY USING 2-D- AND 3-D-COLOR-CODED-DUPLEXSONOGRAPHY Lammers G1 , Poerwowidjojo S1 , Mull M2 ,
Klötzsch C1 , Depts. of Neurology1 and
Neuroradiology2 ; RWTH Aachen, Germany Background: Vessel tortuosity of the proximal vertebral artery
is the main reason for insufficient visualization of stenoses using 2D-color
coded duplexsonography. In addition the differentiation between a stenosis
and a compensatory elevated flow in the vertebral artery caused by a severe
stenosis in the carotid circulation may be difficult. The aim of the present
study was to determine the clinical value of 3D- duplexsonography of the
proximal vertebral artery relative to 2D- duplexsonography in patients with
normal vessel findings and in patients with vertebral artery stenoses. Methods: We
included 25 patients with normal color-coded 2D-sonography findings of the
proximal vertebral artery (Group A; mean age 35 years; range: 19 to 47 years)
and 13 patients with proximal vertebral artery stenosis (Group B; mean age:
67 years; range: 58 to 74 years). All patients underwent additional
3D-sonography of the proximal vertebral artery and the subclavian artery. The
degree of stenosis using 2D-sonography was determined according to
hemodynamic criteria while for 3D-sonography it was calculated using the
intra-stenotic diameter in relation to the post-stenotic diameter (NASCET
criteria). Five patients of group A underwent additional digital
subtraction angiography (DSA). Results: Sufficient
visualization of the proximal 1-2 cm of the vertebral artery at the origin
from the subclavian artery were possible in 15 patients of group A using
2D-sonography (60%) and in 21 patients using 3D-sonography (84%).
2D-sonography enabled a visualization of the suspected pathological area in 7
patients of group B (54%) while 3D-sonography lead to a suitable
demonstration of the stenosis in 11 cases (85%). In one of the five patients
DSA failed to demonstrate a low grade stenosis which was detected with 2D-
and 3D-duplexsonography. Conclusions: 3D-sonography can be used as an additional tool for the detection of proximal vertebral artery stenosis. In comparison to conventional 2D-sonography it is easier to differentiate between extracranial stenosis, vessel tortuosity and compensatory elevated flow of the vertebral artery. |
|
P068 |
CAROTID AND FEMORAL INTIMA-MEDIA
THICKNESS IN ADULT PATIENTS SUCCESSFULLY OPERATED FOR AORTIC COARCTATION Eric de Groot, Joris Vriend, John Kastelein, Barbara Mulder. Departments
of Cardiology and Vascular Medicine, AMC, Amsterdam, Netherlands Background Despite succesful aortic coarctation surgery, cardiovascular mortality and morbidity, notably premature coronary artery disease and cerebrovascular accidents, are greatly increased in middle aged adult post-coarctectomy patients. This may be due to increased blood pressure in pre-coarctatial arterial conduits. Methods B-mode ultrasound imaging can describe status and changes in intima-media complex thickness (IMCT) of carotid and femoral arterial walls. IMTC was investigated in 26 normotensive (SBP≤140mmHg) adult post-coarctectomy patients (31.7(SD9.1)yrs) and age and sex matched controls (33.9(9.9)yrs). Per subject IMTC was defined as average of three right and three left carotid, and two left and two right femoral arterial wall segments. In comparisons of carotid and femoral IMTC per subject averages of arterial conduits were used. Unpaired t-tests were used. Results Post-coarctectomy patient IMTC was increased (0.65(0.17) vs 0.59(0.11)mm: D IMT= 0.06mm, p=0.002). Carotid IMTC was increased increased in patients (0.70(0.10) vs. 0.60(0.09)mm: D IMT=0.14mm, p<0.0001). Femoral IMTC’s were similar: (0.56(0.10)mm vs. 0.57(0.07)mm: D IMT=0.01mm, p=0.64). Conclusions Normotensive post-coarctectomy patients presented with increased carotid IMTC where femoral IMTC is similar to controls. Vascular arterial wall change in post-coarctectomy patients is more appearent in the vascular bed proximal to the former aortic coarctation. This finding reflects increased risk for cardiovascular and cerebro-vascular events in patients. Moreover, the results illustrate the need to investigate multiple vascular beds according to a standardized protocol in order to describe mechanism of disease and improve disease prevention in those at vascular risk. |
|
P069 |
IN-VIVO DUPLEX ULTRASOUND OF CAROTID
STENOSIS COMPARED WITH PLANIMETRIC MEASUREMENTS OF THE CORRESPONDING
POSTMORTEM SPECIMENS G. Schulte-Altedorneburg, D.W. Droste, S. Felszeghy, L. Csiba, V. Popa, L.
Módis, E.B. Ringelstein Departments of Neurology and Anatomy,
University of Debrecen, Hungary Department of Neurology, University of
Münster, Germany Background: The correct detection and quantification of
carotid artery disease is of decisive impact for the patient´s prognosis and
his adequate treatment. In this study, we evaluated the ability of
ultrasonography to detect and to grade carotid artery stenosis by means of a
comparison of the in-vivo ultrasound findings with the planimetric analysis
of the corresponding postmortem specimens. Methods:
Shortly before their death, fifty-nine critically ill neurological patients
(mean age 70 years) were prospectively examined by extra- and intracranial
Doppler sonography, as well as colour-coded duplex ultrasound. Carotid
stenosis was classified by haemodynamical and morphological ultrasound
criteria. Carotid specimens were removed in toto during autopsy. Under
standardised conditions, specimens were redistended, sectioned and
histologically processed. Computerised planimetric measurements of the
arteries were carried out and were compared with the ultrasound findings. Results: Correlation
of the ultrasound and postmortem planimetric findings was available in 93
carotid bifurcations. By means of both techniques 46 carotid arteries were
found to be normal. Stenoocclusive carotid lesions ranged from 8.5 % to 100%
lumen reduction. The overall r was 0.96, and adjusted R2 was 0.90,
respectively. For the stenoocclusive carotid lesions, the r value was 0.91. Conclusion: Extra- and intracranial Doppler and colour-coded
duplex ultrasound permit a reliable detection and quantification of carotid
artery stenoses and occlusions even under difficult examination conditions in
critically ill patients. |
|
P070 |
COLOUR DUPLEX SCANNING IN INVESTIGATION
OF CHILDREN WITH PATHOLOGICAL KINKING OF INTERNAL CAROTID ARTERIES J.V. Smirnova, K.V. Smirnov, M.V. Sidor Altai Diagnostic Center, Barnaul, Russia Background: Previous work shows that the kinking
of internal carotid arteries (ICA) in adults is a common pathology. But the
prevalence of this anomaly in children is unknown. The purpose of study was to investigate
the prevalence and influence of pathology kinking (PK) of ICA upon brain
circulation in children by using Color Duplex Scanning (CDS). Methods: 2520 children aged from 1 month to 15 years old
were investigated. All examined children were divided into four groups: 36
children aged from 1month to 12 months (5,5± 1,2); 32 children aged from
1 to 3 years old (1,9± 0,7); 102 - aged from 3 to 7 years old (5,8± 1,2) and
508 - aged from 7 to 15 years old (10,5± 1,9). CDS of neck vessles were performed by using
ultrasound scaner "Spectra Masters" (Diasonics, USA). Results: It was established that the prevalence of PK of
ICA was the same in all groups. PK of ICA was found out in 26,9 % of
children. This anomaly occured more frequently in the boys (69 %). PK of ICA
more often had the S-shape. The loop was found out in 7,7 % of children. The
C-shape of PK of ICA did not meet. It has been established that PK of ICA in
children was characterized by a marked turbulence of blood flow at the sites
of curves. Belateral PK of ICA was marked at 51 % of the patients. Unilateral
PK of ICA was scanned more often on the right side (60% of cases). In 58 % of
cases unilateral PK of ICA was combined with hemodinamical nonsignify
elongation of opposite ICA. At half of patients the PK of ICA was combined
with a different anomaly of vertebral arteries (VA) such as: elongation and
kinking of V2 and V1, asymmetry of diameters and blood velocities of VA, high
entrance of VA in bone channel and hypoplasia of VA. In children with PK of
ICA the symptoms of chronic cerebrovascular insufficiency were dominated. In
19,5 % of cases the epilepsies syndroms were established. The transitor
ishemic attack were reveled in 4,4 %. 72 children with PK of ICA were examined
several times during 6 years. It is necessary to note that the shape of
kinking and hemodinamical desorders did not change with age. Conclusion: Thus, the PK of ICA is a common pathology in
children. The PK of ICA may be cause of brain circulation disorders and
epilepcy in children. The shape and hemodinamical infringements in children
with PK of ICA have no any positive dynamic changes with age. The results
received by using CDS of neck vessels in children testify that this anomaly
has inherent character. |
|
P071 |
A parental history of early stroke is
independently and specifically associated with early carotid bulb
arteriosclerosis Sitzer M, Jerrard-Dunne P*, Steckel DA, Buehler A, von
Kegler S, Markus HS*. Dept. Neurology, J.W. Goethe-University Frankfurt/Main,
Germany; *Div. Clin. Neurosciences, St. Georges Hospital. Medical. School,
London, UK Background: Carotid artery intima-media-thickness (IMT) is an
intermediate-phenotype for studies of candidate stroke genes. However, genes
may predispose either to stroke risk itself, or merely to conventional
risk-factors. We hypothesised that a measure of "unexplained" IMT
might be a useful way of identifying individuals with a specific genetic
predisposition to carotid atherosclerosis, independent of conventional risk
factors. Methods: Using IMT measurements and regression modelling we
determined the proportion of IMT that remains unexplained after controlling
for vascular risk-factors ("IMT residuals"). In a middle-aged
community population (n=5460), we determined whether parental history of
stroke is associated more strongly with this measure of unexplained
atherosclerosis than with unadjusted IMT values and whether these
associations differed at specific sites in the carotid arterial tree. Results: A parental history of stroke £ 60 years
was strongly associated with increased carotid BULB IMT residuals- odds-ratio
(OR) for BULB IMT residuals in the upper quartile 2.14(1.59-2.89),
p<0.001. The association with common carotid artery (CCA) IMT residuals
was much weaker - OR 1.21(0.87-1.70), p=0.262. In contrast there was no
relationship between a parental history of young myocardial infarction and
BULB IMT residuals, but a highly significant association with CCA IMT residuals-
OR 2.18(1.75-2.71) p<0.001. All associations were much weakened when
unadjusted IMT values were used. Conclusions: Internal carotid BULB IMT is more strongly
associated with familial stroke risk than CCA IMT. Future candidate gene
studies may be more successful if they determine associations with carotid
BULB IMT, as opposed to CCA IMT. Our measure of "unexplained" IMT
identifies individuals with a particularly strong genetic component, which is
independent of conventional risk-factors. |
|
P072 |
Internal Carotid Artery Angle of Origin
– A Novel Risk Factor for Early Carotid Atherosclerosis Sitzer M, Puac D, Buehler A, Steckel DA, von Kegler S,
Markus HS*. Dept. Neurology, J.W. Goethe-University Frankfurt/Main, Germany;
*Div. Clin. Neurosciences, St. Georges Hospital. Medical. School, London, UK Background: Established ‘systemic‘ vascular risk factors do not
fully explain the occurrence of atherosclerosis at the carotid bifurcation.
Local anatomical and hemodynamic factors may also influence the initiation of
the atherosclerotic process. We determined whether the angle of internal
carotid artery (ICA) origin is a risk factor for early atherosclerosis. Methods: In 1300 normal population individuals aged 40-70
years, we measured both carotid intimal-media thickness (IMT) at three
arterial sites (common carotid artery, CCA; bifurcation, BIF; internal
carotid bulb, BULB), and the presence of any atherosclerotic plaque within
the BULB on both sides by means of high-resolution ultrasound. A standardised
transverse insonation was used to determine the angle of ICA origin,
expressed as the angle of rotation relative to the external carotid artery. Results: This angle was positively associated with
BULB-IMT but not with IMT at other sites. After controlling for age, gender
and other cardiovascular risk factors each 15° increase in the ICA angle of
origin conferred an odds ratio (OR) for having an IMT in the highest quartile
of 1.25 (95% CI, 1.12-1.40) on the left and 1.22 (1.11-1.35) on the right,
both p<0.001. A similar relationship was found for plaque. On multivariate
analysis these odds ratios were 1.38 (1.10-1.72) on the left and 1.33
(1.10-1.60) on the right side, both p<0.025. Conclusion: This study provides the first evidence that the
angle of ICA origin is an independent risk factor for early atherosclerotic
changes at the ICA bulb. |
|
P073 |
Evaluation of a Screening Protocol for
Carotid IMT using a hand-held Ultrasonography Instrument U. Schminke, R. Tang, J.H. Burkart, M.G. Bond Wake Forest University School of Medicine,
Winston-Salem, USA and Ernst Moritz Arndt University Greifswald, Germany Background: Although it has been proposed to include carotid
artery IMT ultrasound measurement as a part of screening procedures for
cardiovascular risk assessment, this method is still regarded as a research
tool because of high instrument costs, and complex scanning and reading
protocols that are performed exclusively in specialized ultrasound reading
centers. However, IMT measurements would become more feasible if simple
screening methods were available to measure carotid IMT during clinical
practice. Methods: Three different IMT measurement protocols were
applied to 41 patients with end-stage renal disease receiving hemodialysis
treatment. (1) Standard scanning and reading protocols using a duplex
sonography instrument (AU 5, Biosound Esaote, Italy); (2) the same standard
protocol using a hand-held, lightweight (2.4 kg) ultrasonography device
(SonoSite 180, Bothel, WA, USA); and (3) an abbreviated screening protocol,
in which IMT measurements were performed by the sonographer on frozen digital
images during the exam. For each exam, the average time cost was
approximately 60 minutes using the standardized research protocol and 10
minutes using the screening protocol, respectively. Results: The average absolute difference of the mean carotid
IMT (MMax) using standard research protocols and comparing the two
instruments was 0.1 mm (correlation: r = 0.84). Comparing the research with
the screening protocol, the absolute MMax IMT differences were 0.3 mm,
regardless of combination of instruments used (correlation r = 0.47 and 0.56,
respectively). Conclusions: The present study demonstrates the feasibility of using a screening protocol for assessment of carotid IMT, even if applied in a worst case scenario involving patients with advanced atherosclerosis. Using a portable hand-held instrument that can be hand carried allows carotid IMT screening independently of expensive stationary laboratories. |
|
P074 |
THROMBUS IN THE INTERNAL CAROTID ARTERY
COMPLICATING AN « UNSTABLE » ATHEROMATOUS PLAQUE F. Perren, L. Urbano, A. Rossetti, L. Von Segesser, P.-A.
Despland, J. Bogousslavsky, G. Devuyst, CHUV, University of Lausanne,
Switzerland Background: To report and illustrate with 4 dynamic B-mode
high-resolution and Duplex imaging cineloops, the importance of arterial wall
imaging in acute cerebrovascular disease. Method/Results: A 64-year-old healthy man, under treatment of
pravastatin was admitted to our stroke unit following brief clumsiness of the
left hand associated to ipsilateral numbness one week before. Neurological
examination disclosed a left-sided sensory deficit. MRI of the brain revealed
a subacute infarction of the right fronto-parietal region suggesting a
"borderzone infarct". Extracranial ultrasound examination showed
a non-stenotic, heterogenous plaque with an interrupted "fibrous
cap" (FC) situated at the origin of the right internal carotid artery
(ICA). The patient treated under anticoagulants
could be rapidly discharged; unfortunately he had to be readmitted 10 days
later after recurrence of left sensitive symptoms. An extracranial ultrasound
was again performed and revealed the presence of an isoechoic pulsating mass
attached to the plaque previously seen in the right ICA. This finding
strongly evoked a floating thrombus, which was confirmed by MRA. The patient
underwent emergency ICA thrombendarterectomy which allowed to remove the
suboccluding fresh thrombus from the above mentioned plaque. Conclusions: This case illustrates well the new concept of unstable atherosclerotic plaques described by the cardiologists and probably applicable to the ICA. We consider that at least some ischemic stroke could be the consequence of the rupture of a lipid-laden coronary plaque covered by a thin FC from a carotid atheromatous plaque. We want here to highlight the importance of ultrasound as a useful diagnostic tool to explore the emergence of a fresh thrombus on an "unstable plaque". |
|
P075 |
ULTRASONIC ASPECTS OF COMMON CAROTID
ARTERY THROMBUS. J.M. de BRAY 1, G. DEVUYST 2,
J BOULLIAT, J.O. FORTRAT 3, F. DUBAS 1, A. ROSSETTI 2,
J. BOGOUSSLAVSKY 2. 1 – Département de Neurologie-Larrey – CHU
- 49033 ANGERS cedex 01 2 – Département de Neurologie – CHU
Vaudois – LAUSANNE 3 – Laboratoire d’Explorations
Fonctionnelles Vasculaires – CHU – 49033 ANGERS cedex 01 Carotid artery thrombi are uncommon
(Buchan , Caplan, Akins, Devuyst) but they cause strokes and could be
misdiagnosed by ultrasonic methods .Our aim is to analyse the color Doppler
flow imaging finding, in 6 cases of ³ 70 % common carotid thrombus without identifiable
carotid disease by this investigation . POPULATION. 3 females and 3 males, mean
age 53 ± 11 years, have been admitted for a stroke in 5
cases and for transient ischemic attacks in 1 case. All were studied by
Duplex scanning then by intra arterial angiography or MR angiography. RESULTS. The thrombus was always
hypoechoic with a regular linear surface. It was located 1 to 2 cm before the
carotid bifurcation and respected the intima media layer. This fact allowed
to exclude a dissection and did not seem in favor of an atheroma disease.
This lesion could be a soft thrombus since it was compressible by the probe
and gave no increase of blood flow velocities within the residual lumen. This aspect was assessed by angiography
and by pathological studies in 3 cases, all the patients were treated by
intravenous Heparin. Two thrombi were resolutive, 4 were operated, followed
by a stroke in 1 case. The main causes of this series were an
atheroma, a presumed paroxystic arythmia. an essential thrombocythemia and a Sneddon
Syndrom DISCUSSION. These thrombi seem exceptional
but have characteristic ultrasonic aspects. They could be misidentified if
the Duplex scanning examination was late or incomplete on this site. An hypercoagulable status with local turbulences could favor this soft thrombus, but a minimal atheroma ulceration unrecognized by ultrasound was present in 3 cases . |
|
P076 |
ACCELERATION OF THROMBOLYSIS IN ACUTE
STROKE PATIENTS BY TCCS MONITORING – CASE REPORTS D.Skoloudik, M.Bar, P.Hradile, M.Häringova Faculty Hospital Ostrava-Poruba Some in vitro and in vivo experiments
indicate that ultrasound can accelerate thrombolysis. We started to use TCCS
monitoring in acute stroke patients. We report results of our first four
patients. Methods: In January and February 2002 we admitted to Dept.
of Neurology four patients with acute stroke in MCA territory and with TCCS
finging of MCA occlusion (main stem or branches occlusion). We performed
60-minutes TCCS monitoring with maximum energy. It started 60-150 minutes
after stroke onset (median 118 minutes). One patient was treated with IV
rtPA. Results: Mean NIHSS score at admission was 13.8 (8-18), at
1 hour after start of TCCS monitoring NIHSS score was 3.8 (0-6) and at 24
hour it was 1.8 (0-4). In all cases we detected recanalization of occluded
artery between 18 and 27 minutes after beginning (mean 24 minutes). In 3
patients was detected complete recanalization within 1 hour, in the last
patient it was at 24 hours. Mean Rankin score at day 7 was 1 (0-2). Discussion: Acceleration of thrombolysis by ultrasound could be a perspective method of acute stroke treatment. It could improve outcome of patients treated by rtPA (Alexandrov 2000) and without thrombolytic treatment too (Cintas 2002). Conclusion: TCCS monitoring could improve outcome of acute stroke patients but it must be properly investigated further. |
|
P077 |
Cag-A positive Helicobacter pylori strains
and IMT in different stroke subtypes: a possible role in progression of
atherosclerotic process. M. Diomedi, B. Rizzato, L.M. Cupini, A. Pietroiusti*, F.
Ferrante, M. Silvestrini** Neurological Clinic and * Medical
Semiology and Methodology, University of Rome Tor Vergata;**Neurological
Clinic, University of Ancona: Italy Background: Several studies have discussed about the
possibility of an involvement of chronic bacterial infections in
atherosclerotic process and in predisposing to an increased risk of
cardiovascular and cerebrovascular diseases. The aim of this study was to
evaluate the possibility of a relationship between virulent H. pylori
(HP) strains infection, the evolution of atherosclerotic process and
the occurrence of different stroke subtypes. Method: 145 consecutive patients with acute first ever
ischemic stroke were included in the study. According to TOAST criteria on
the basis of neurological manifestations, neuroimaging and clinical history,
ischemic events were classified in 1) large artery stroke (55); 2) lacunar
stroke (42); 3) cardio-embolic stroke (48). 143 controls were recruited among
the relatives of patients and were matched for age and sex. Serum titres of IgG
antibodies against H. pylori, seropositivity and IgG antibodies
to cytotoxin-associated gene-A (CagA) protein, a strong virulence factor,
were determined by enzyme linked immunoadsorbent assays. In stroke patients,
inflammatory markers (C-reactive protein, withe blood cell count, SER,
fibrinogen, a 1 antitrypsin, a 1 acid glycoprotein) were
also evaluated. All subjects performed a complete ultrasonographic study of
extracranial vessels to evaluate plaque status and intima-media thickness
(IMT) on the common carotid arteries, along » 1.5 cm proximal to the flow
divider. Results: The titre of HP antibodies, CagA seroprevalence,
and mean IMT were significantly higer in patients than in controls. Among
stroke subgroups, the seroprevalence of CagA positive strains was
significantly higher in large artery stroke in comparison to lacunar stroke
and cardio-embolic stroke, whereas IMT was significantly higher in patients
with large artery stroke in comparison to patients with lacunar stroke.
Differently from the other stroke subtypes, in lacunar patients there was a
significative correlation between IMT and serum titre of antibodies to HP.
Plaque status was not correlated with HP infection or with the presence of
Cag-A positive strains. Conclusions: The evolution of the atherosclerotic process, as showed by a thickening of vessel wall, seems to be influenced by a significantly higher immune response towards a chronic infection and by the presence of virulent H. pylori strains. An increased IMT in lacunar stroke might help to identify a subgroup of patients at risk for the subsequent development of large artery stroke. |
|
P078 |
CAROTID INTIMA-MEDIA THICKNESS IN
HEALTHY KOREANS: IS IT ALSO USEFUL IN CEREBROVASCULAR RISK ASSESSMENT IN
INTRACRANIAL DISEASE PRONE POPULATION? Kim YJ1, Park KD1, Choi KG1, Han SR2,
Kho SB2, Cho HG1, Heo GB3 EWHA Womans Univeristy1,
Catholic University of Korea2, Yonsei University3,
SEOUL, KOREA Background: Carotid intima-media thickness (IMT) measurements
are being applied widely as a measure of atherosclerosis. There is a growing
belief that changes in carotid IMT is associated with atherosclerosis elsewhere
in the arterial system. However, evidence of an association between carotid
IMT and intracranial atherostenosis is sparse. Data on IMT has been available
mostly from studies of whites. Unlike whites, atherostenosis arising within
the intracranial arteries, especially of medium-sized branches, is common in
Asian people. We investigated the hypothesis that extracranial carotid IMT is
also useful in stroke risk assessment in Korean individuals, whose major
stroke subtype is intracranial atherosclerosis. Methods: Noninvasive measurements of the IMT of the common
carotid artery were made with high-resolution B-mode ultrasonography in 1,230
healthy subjects, living in the district of Hwagock in Seoul, Korea. Detailed
information about number of parameters, including classical risk factors of
stroke, was gathered. Results: IMT was significantly correlated with age and systolic blood pressure (p<0.05). However history of smoking and fasting sugar were correlated weakly with IMT without stastical significance. Alcohol intake was not related to IMT. Though it made a room for further analysis, this preliminary data showed that carotid IMT might be an useful tool in stroke risk assessment also in intracranial disease-prone group. |
|
P079 |
THE OXFORDSHIRE COMMUNITY STROKE
PROJECT CLASSIFICATION PREDICTS FOR SYMPTOMATIC OCCLUSIVE EXTRACRANIAL
CAROTID DISEASE RU Esagunde, CLHP Chen, HM Chang Singapore General Hospital, Singapore Background: The Oxfordshire Community Stroke Project (OCSP)
classification may be useful in predicting stroke aetiologies, such as
symptomatic severe extracranial carotid disease (SSECD), and hence may have a
role in selecting appropriate investigations. Methods: Patients were identified from the Singapore
General Hospital Brain Centre Stroke Database which prospectively classified
patients using the OCSP criteria and documented the presence or absence of
SSECD ( 70-100%) by Doppler and duplex studies. Results: Over a 2-year period from January 1999 to
December 2001 , 2585 stroke patients were admitted. 111 with intracerebral
hemorrhage, 735 without Doppler studies and 197 POCI were excluded. 1542
patients were included in the analysis. 56% were male and the mean age was
65.3 years. 81.6% were Chinese, 10.1% Malays, 5.9% Indians and 2.4% other
races. OCSP classification was 5.6% TACI, 15.7% PACI, 66.1% LACI and 12.6%
TIA . SSECD was found in 6.7% of patients. Univariate analysis showed that
SSECD was more common in male patients (p<0.01), and in patients with TACI
(16.2 %), PACI (11.9 %) or TIA (10.2 %) compared to LACI (3.9 %). Patients
with SSECD were also significantly older. Logistic regression analysis showed
that age, gender and OCSP classification independently predicted for SSECD. Conclusions: SSECD is more common in patients with TACI, PACI and TIA. It is also present in a small percentage of LACI strokes. As carotid endarterectomy is beneficial in non-disabling strokes, our results suggest that all TIA and PACI strokes should be screened. The cost benefit of screening LACI is yet to be determined. |
|
P080 |
b -Fibrinogen Gene Polymorphism (-455G/A) Is Mediated
Inflammation Degree and Is Associated With Asymptomatic Carotid Artery
Atherosclerosis E Ben-Assayag¹, I Bova², D Zeltser³, S Berliner³,T Nissel², S
Lorenz M Levkovski², I Shapira³, N Bornstein² ¹Dpt. of Human Genetics and Molecular Medicine, Sackler Faculty of
Medicine, Tel-Aviv Universisty,
Dpt. of ²Neurology and ³Internal
"D", Tel-Aviv Sourasky Medical Center, Israel Background: The -455G/A polymorphism at the promoter region of
the b -fibrinogen gene has been related to plasma fibrinogen concentration
and to the severity of coronary artery disease, the progression of atheroma,
thrombosis risk and was associated with stroke in Japanese. Since fibrinogen
is an acute-phase protein, an increased plasma fibrinogen level may reflect
the inflammatory state of the vascular wall. Inflammatory processes may
facilitate the transition of clinically stable to unstable atherosclerotic
plaques. Methods: We investigated the relation of this polymorphism
with carotid atherosclerosis and inflammation in 162 neurologically
asymptomatic individuals. Atherosclerosis was quantified as intima-media
thickness (IMT) measured in the common carotid artery and degree of stenosis
measured in the internal and external carotid arteries by high-resolution
ultrasonography. Inflammation examined using common inflammatory markers and
erythrocyte aggregation test by a simple slide technique and image analysis. Results: The b -fibrinogen -455G/A polymorphism was significantly
associated with elevated inflammatory degree and atherosclerosis: elevated
plasma fibrinogen level (p=0.033), high-sensitive CRP (p=0.011), WBC
(p=0.004), erythrocyte sedimentation rate (ESR), plasma interleukin-6 and
increased degree of stenosis in the right carotid artery and slightly
increase in mean IMT in the right common carotid artery. Individuals
homozygous for the A allele had very high correlation between plasma
fibrinogen and ESR (r=0.91, p=0.001) versus individuals homozygous to the G
allele (r=0.62, p=0.000). The homozygous AA individuals presented also very
high correlation between their other inflammatory markers, erythrocyte
aggregation and with their IMT. Conclusions: These data suggest that the A-455 allele of the b -fibrinogen promoter is associated with elevated inflammation and increased susceptibility for atherosclerosis in the carotid artery. The data suggest that their fibrinogen is more adhesive, and therefore they have such high correlation between their fibrinogen and ESR. Due to their baseline inflammatory degree, individuals homozygous for the fibrinogen –455A allele may be at particular risk for thrombotic event following an acute phase stimulus. Once identified, they may benefit from risk factor reduction and early therapy with statins or anti-inflammatory agents. |
|
P081 |
DIFFERENCES IN CEREBRAL HAEMODYNAMICS
IN FEMALES WITH MIGRAINE. TCD STUDY. Lutfiyya Khalilova MD., Yunus Efendiev MD. Institute of Physiology, Academy of
Science, Baku, Azerbaijan Background: In the study we have evaluated cerebrovascular
reactivity to hypercapnia that occurs in women suffering from migraine,
before and after menopause. Methods: 23 premenopausal (mean ± SD age 34 ± 7) and 21
postmenopausal (48 ± 6) females were studied during headache-free periods as
well as during migraine attacks. Cerebral reactivity was evaluated with the breath holding index (BHI). Bilateral TCD measurements of mean flow velocity (MFV) in the MCA and ACA before and after breath holding have been used to evaluate possible side asymmetries. The same measurements were recorded in two
control groups of women of the same age, who had no symptoms of classic
migraine. The examination was performed with "Angiodin" TCD unit
(BIOSS, Russia). Results: In the younger group of women with migraine, BHI
was much lower (0.78 ± 0.4) than in the older group (1.49 ± 0.4). These
results are comparable with those of the premenopausal (0.70 ± 0.5) and
postmenopausal (1.63 ± 0.7) control groups. BHI values during the period of
migraine attack was reduced in 70% of the migraine patients and was similar
both in the headaches presenting and headaches free head sides in all
arteries During the headache-free period, there was
no detectable BHI differences between the all groups. Marked MCA MFV
asymmetry was found in 29% of the patients with migraine and only in 9 % of
the "healthy" patients group. At all the tests, the variability of MFV
was significantly higher in the migraineurs than in the control group of
women. Conclusions: TCD cerebrovascular reactivity tests proved to be diagnostically insufficient for examining the patients with migraine. BHI in postmenopausal females could be considered as a factor influenced by hormonal disturbances, and age. Failure of cerebrovascular regulation occurs during migraine attacks. |
|
P082 |
THE TRANSESOPHAGEAL ECHOCARDIOGRAPHY
AND ISCHEMIC STROKE Tavciovski D, Raicevic R*,Markovic Lj**, T.Lepic*, M.Cvejic*.
Department of Neurology*, Department of Cardiology, Department of
Radiology**. Military Medical Academy, Belgrade, Yougoslavia. Introduction. Ischemic stroke (IS) represents unique clinical
entity with various ethiological factors. Embolic mechanisms of development
with thrombotic material of cardiac origin is the cause in 20-50% of the
cases.The aim of the study was to determine the significance and sensitivity
of TEE in detection of cardiac abnormalities which are considered to be the
small risc source in patients with IS in which the embolic mechanism of
disease development was suspected. Methods and results: We examined 80 patients with acute acute IS, proved
according to clinical and radiological criteria, of probably cardioembolic
development mechanism and by transthoracal(TTE) and TEE peformed by two
examiners in order to exclude bias.Significance of diferences in detection of
cardiac abnormalities was determined by statistical calculations.In patients group
examined by TEE mitral valve prolaps was detected in 24 patients(was detected
in 13 cases when TTE was used). Atrial septal aneurism was detected in 11
patients by TEE and with only 2 positive finding when TTE was used.
Spontaneous echo contrast was seen in 7 cases only by TEE method. Conclusions: According to our results,we can conclude that TEE is significantly more sensitive diagnostic method for detection of small risk cardioembolic sources in development of IS which is specially related to younger patients. |
|
P083 |
EFFECT OF ANTIHYPERTENSIVE TREATMENT ON
CO2 REACTIVITY OF CEREBRAL ARTERIOLES DURING PHYSICAL EXERCISE T. Magyar, A. Valikovics,* I. Czuriga, L. Csiba. Departments of Neurology and * Cardiology,
University of Debrecen, H-4012 Debrecen, Hungary Background: Previously, 30 untreated hypertensive patients
(mean age 42.4 + 5.4 years) were investigated by transcranial Doppler monitoring during physical exercise, and changes of hemodynamic parameters were compared with those of age-matched healthy subjects. The aim of this study was to investigate the effect of 3-year antihypertensive treatment on cerebral hemodynamics in hypertesives during ergometer cycling. Methods: Until now, 12 out of 30, previously untreated
hypertensive patients were investigated after 3-year antihypertensive
treatment. The examination will be continued. Blood pressure, heart rate,
end-tidal CO2 (Capnogard capnograph), and MCA mean blood flow
velocity (Multidop X DWL) were continously monitored during ergometer cycling
according to the WHO protocol. Our preliminary results: Loading time of the 1st and the 2nd
examination didn't differ significantly (mean + SD: 4.58 + 1.92
and 4.41 + 1.67 min). Systolic blood pressure decreased after 3-year
treatment (mean + SD: 176.16 + 11.35 mmHg and 162.66 +
21.81 mmHg) (p< 0,05). Unfortunately, out of 12 patients 3
hypertensives didn't take any antihypertensive drugs. In one of them, maximal
CO2-reactivity during exercise decreased from 1.82 cm/s/mmHg (1st)
to 1.54 cm/s/mmHg (2nd examination) after 3 years. Otherwise, in
one of 3-year regularly treated patient maximal CO2-reactivity
increased from 1,38 cm/s/mmHg (1st) to 2 cm/s/mmHg (2nd
examination). Conclusions: TCD combined with ergometer cycling might be useful for evaluation of therapeutic efficacy. |
|
P084 |
Impaired dynamic cerebral
autoregulation in eclampsia? E. Oehm, M. Reinhard, J. Spreer1, C. Keck2,
T. Els, and A. Hetzel Department of Neurology and Clinical
Neurophysiology, University of Freiburg, Germany 1 Section of Neuroradiology, University of Freiburg, Germany 2 Department of Gynaecology and Obstetrics, University of Freiburg,
Germany Background: Eclampsia accounts for 24-47% of ischemic stroke
during pregnancy or the puerperium. It causes cerebral arteriopathy, leading
frequently to dilation of arteriolar vessels and arterial vasospasms,
resulting in cerebral edema or infarction. We analysed the vasodilatory response
by CO2-reactivity testing and dynamic cerebral autoregulation
(DCA) by transfer function phase between spontaneous oscillations of arterial
blood pressure (ABP) and cerebral blood flow velocity (CBFV) in an eclamptic
woman. Case Report: A 28 year old primaparous woman with normal
pregnancy presented 3 days after delivery with preeclampsia. On the fifth day
postpartum sudden manifestation of reduced consciousness, bilateral cortical
blindness and generalized seizures occured. T2-weighted MRI revealed cortical
and subcortical, as well as deep white matter lesions, most pronounced in the
occipital and parietal lobes. Venous and arterial MRA showed normal findings.
Control MRI two months later documented a complete resolution of the lesions.
CSF analysis, vasculitis and hemostasis screening, HSV 1+2 and VCV PCR were
normal. TCD demonstrated increased CBFV in both MCA and ACA. CO2-reactivity
of right MCA was reduced to 1,2%/mmHg (normal range: 1,5-4%/mmHg).
Cross-spectral analysis revealed significant coherency values between ABP and
CBFV (right MCA) at 0.1 Hz. Phase shift was substantially reduced to +5°
(normal range: +60± 30°). Neurological symptoms resolved within 5
days. Conclusions: To our knowledge, we present the first case of impaired DCA, as documented by decreased transfer function phase, in eclampsia. The vasodilatatory response was only slightly reduced compared to severely altered DCA, suggesting dissociated vasoparalysis, a condition described as diffuse loss of cerebral autoregulation with widely preserved vasomotor reactivity. |
|
P085 |
THE EFFECTS OF ACUTE SMOKE ON THE
CEREBRO-VASCULAR SYSTEM ARE DIFFERENT IN QUOTIDIAN VERSUS OCCASIONALLY
SMOKERS V. Bohotin, C Bohotin, D Baltag, CD Popescu University of Medicine and Pharmacy Iasi Romania Background : The acute systemic haemodynamic effects of the cigarette smoking are well known, but there are no studies dealing with the possible smoke-related changes of cerebral circulation. Objective : In the present study we evaluated the acute
effects of cigarette smoking on blood flow velocity of the internal carotid
artery by use of extracranial Doppler ultrasound in people who smoke at least
15 cigarettes/day (quotidian smoker CS)and in people who smoke occasionally
less then 5 cigarette/month (occasionally smoker OS). Methods : Twenty five normal volunteers (15 CS and 10
OS with a mean age of 24 ± 3 years) were asked to smoke one cigarette with a
total known nicotine content (1.1 mg) during a five minutes period. Using
extracranoial Doppler we measure the systolic, diastolic and mean flow
velocity and resistivity index in right internal carotid artery before and
immediately after a cigarette smoke. Results : No significant difference was found in the baseline
condition between the two groups. The resistance index increase after
cigarette smoke. The increase is more evident in OS group but is also present
in CS group. (IR 0.56 ± 0.09 before and 0.85 ± 0.05
after in OS group before 0.58 ± 0.08 and after 0.79 ± 0.06 CS group). The systolic
and diastolic flow velocity increase was not significant. There is an
increase of the heart rate from 65 ± 8 to 76 ± 11.and of the blood pressure from 120/75 mmHg to
155/90 mmHg which is not different in the two groups. Conclusion : The cigarette smoke induce an sudden vasoconstriction of the cerebral vascular bed more pronounced in the occasional smoker reflected by an increase of the resistance index which could induce a decrease of the blood supply to the cerebral tissue. |
|
P086 |
CEREBRAL AUTOREGULATION IN PATIENTS
WITH MIGRAINE AND TENSION HEADACHE Z. Kazibutowska, A. Gołba, A. Bal,
A. Warsz-Wianecka, J. Machowski Neurological Clinic SLAM Katowice, Poland Background. Headache etiology is heterogeneous and still unknown.
The most recent findings delineate three mechanisms: autonomic, vascular and
neuronal (n. trigeminal). The increased arterial reactivity and serotonin
metabolism disturbances are postulated. The data imply that vascular
abnormalities observed in migraine may be secondary to a primary
abnormalities in neuronal function in the brainstem. Vascular mechanism in migraine is based on
changes in cerebral flow as follows: angiospasm causing visual deficit
(aura), next vasodilatation causing pain and oedema. The studies examining
cerebral blood flow try to characterize vasomotor sensitivity and explain
whether cerebral autoregulation is intact or impaired in patients with
migraine end tension headache. The aim of this study was to evaluate the mean velocity blood
flow (mVBF) and pulsatility index (PI) in middle cerebral artery (MCA) during
normocapnia, hypocapnia and relative hypercapnia in patients with migraine
and tension headache. Methods. Transcranial Doppler sonography was performed in 20 patients diagnosed with migraine, 20 with tension headache and 20 control subjects matched in age and sex to the patient group. There were mVBF and PI measured in right
middle cerebral artery at rest, next after 30-sec hyperventilation test and
after 5% CO2 + 95% air rebreathing for 3 min. The time of return these
parameters to baseline values was measured. Results. The mean velocity flow in MCA at rest is higher
in patient with migraine in comparison with patients with tension headache
and control group. The decrease of mean velocity flow in MCA
after HV test was greater and faster in patients with migraine. PI increased 2-fold more during HV test in
patients with migraine vs patients with tension headache. The return mVBF in MCA and PI after HV
test and rebreathing CO2 + air to baseline values was faster in patients with
migraine in comparison with patients with tension headache. Conclusions. Approximately 2-fold more cerebral vasoreactivity in patients with migraine vs patients with tension headache can be associated with small vessels diameter changes dependent on autonomic mechanism. |
|
P087 |
ESTROGENE-PROGESTERONE THERAPY
INFLUENCE ON CEREBRAL BLOOD FLOW DISORDERS IN TRANSCRANIAL COLOR DOPPLER
MEASUREMENTS. E.Kudybka-Glownia;J.Siejka-Jurenczyk Neurology d.,Municipal Hospital
Katowice-Murcki,Poland A
group of 40 women at the age 25-55y.o.,during or after finishing hormone
therapy /supplementary or contraceptive h.th./ had been examined.Patients
suffered from headaches,dizziness,transient or fixed speech abnormalities and
weakness of the limbs-in 55% of the right side.Neurological examination
showed senso-motorial aphasia/30%/,pyramid symptoms /75%-on the right side/
and cerebellar symptoms/20%/. Transcranial
Color Doppler/TCD/ examination performed invariably showed cerebral blood
flow/CBF/ disorders /Vmax decrease,turbulances,no echo in the cerebral
arteries/ concerning the left brain hemisphere in 95% of patients;bilateral
abnormalities concerned 5%group of elderly patients.EEG rutine procedure
showed vascular record in 80% of patients. Blood examination showed high
coagulability /INR 0,9-1,1/ in 60% of cases;lipids level increase occured in
40% of elderly patients.Anticlot treatment,finishing hormone therapy
/supervised by gyneacologist/ and motorial rehabilitation gave improvement of
neurological state. Taking into consideration majority of disorders in the left brain hemisphere,we suggest that because of anatomical difference between precerebral vessels of the left and right side , left hemisphere is more exposed to pharmacodynamic consequences od drugs activity /e.g.influence of h.th.on blood thickness/. |
|
P088 |
CHANGES IN BASILAR ARTERY BLOOD FLOW IN
PATIENTS WITH SYNCOPE OF UNKNOWN ORIGIN Z. Kazibutowska, A. Gołba, A. Bal, A.
Warsz-Wianecka, J. Machowski Neurological Clinic SLAM Katowice, Poland Background: Differential diagnosis of syncope frequently
imposes a major problem in clinical practice.Previous work shows that
cerebral blood flow changes alone , in the absence of systemic hypotension ,
may result in syncope. We use Transcranial Doppler
Ultrasonography to asses basilar cerebral artery mean flow velocity (Vmean)
and pulsatility index (PI) during orthostatic challenge and CO2 reactivity
testing. Methods: Twenty five patients with history of cerebral
syncope and twenty healthy controls were examined .Basilar cerebral artery V
mean and PI and end –tidal pressure of carbon dioxide were measured in
patients et rest during normocapnia , after 30 –second hyperventilation and
during hypercapnia. The same parametres were assesed under
postural stress. Results: Et rest basilar cerebral artery V mean was
significant lower in patients with syncope during normo- hypo- et hypercapnia
.They have also higher values of PI but it was nonsignificant.Under postural
stress in patients with syncope a significant increase in V mean and decrease
of PI can be observed. Conclusions: TCD measurements may represent e new approach to the work-up of patients with syncope of unknown origin.In those patients myogenic mechanism of cerebral blood flow autoregulation may an important role in derangement of cerebral autoregulation with resultant cerebral hypoxia. |
|
P089 |
INNOVATIVE NONINVASIVE TECHNOLOGY FOR
LONG - TERM CEREBROVASCULAR AUTOREGULATION MONITORING A.Ragauskas1, G.Daubaris1, V. Ragaisis2 1Kaunas University of Technology and 2Kaunas Medical
University Neurosurgical Clinic, Kaunas, Lithuania Background: The ultrasonic "time-of-flight"
monitoring technique (Vittamed) was investigated in our previous works (1-3).
This technique can be used for up to 120h of patients‘ continuous
cerebrovascular autoregulation (CA) monitoring because it‘s brain insonation
energy is 180 times less comparing with the standard TCD technique. The
objectives of this study are to show the similarity between invasively
recorded ICP slow B waves and simultanesouly noninvasively recorded
intracranial blood volume slow waves and also to prove the reliability of the
"time-of-flight" long-term CA noninvasive monitoring technology
under ICU conditions. Methods: A new noninvasive "time-of-flight"
monitor (Vittamed) has been used at first time in ICU for clinical study of
CA simultaneously with invasive ICP and ABP slow wave monitoring techniques.
One hour CA monitoring sessions have been repeatedly performed on 12 patients
with traumatic brain injuries (10 M, 2 F, age average 26 years). Data were
collected from 83 one hour sessions of simultaneous invasive and noninvasive
intracranial slow B wave monitoring and from 55 one hour sessions of invasive
and noninvasive CA monitoring. Bland & Altman plots were used to assess
the agreement between invasive and noninvasive slow wave and CA monitoring
data. Results: It has been shown experimentally that the reliable
long-term continuous noninvasive CA monitoring (Vittamed) can be used
interchangeably with invasive CA monitoring under ICU conditions. The
statistically estimated (Bland & Altman) difference between invasively
and noninvasively recorded intracranial slow B waves (standard deviation
SD=0.089, p=4.5x10-7) and the difference between invasively and
noninvasively recorded CA indexes (SD=0.05, p=1.1x10-6) are small
enough and such differences are not clinically important. Conclusions: In this clinical study it is shown at the first
time that ultrasonic "time-of-flight" technique (Vittamed) provides
reliable information about cerebrovascular autoregulation state during
long-term continuous noninvasive monitoring. 1. Cerebrovasc Dis 1999;9 (suppl.2):31,
46; 2. Cerebrovasc Dis 2000;10 (suppl.1):34; 3. Cerebrovasc Dis 2001;11 (suppl.3):44 This work is supported by US DAMD Award
17-00-2-0065
|
|
P090 |
CEREBROVASCULAR REACTIVITY TO VISUAL
STIMULI 1Zaletel M,
1Žvan B, 2Štrucl M, 1Pogačnik T 1University Clinical Center, Dept. of Neurology, 2School of
Medicine, Institute of Physiology, Ljubljana, Slovenia Cerebrovascular reactivity (CVR) to
complex visual stimuli is higher compared to simple-white stimuli. It is not
clear, whether CVR to red light stimuli is different compared to simple–white
stimuli and complex stimuli. Methods: 19 healthy volunteers (mean age 29± 6.7
years) participated in our study. Visually evoked flow responses (VEFRs) were
measured in the posterior and middle cerebral arteries by 2 MHz probe using
TCD monitoring system. Mean arterial pressure was continuously measured by
Tonometer, End-tidal (Et-CO2) was monitored by infrared
capnograph. Stimulus was applied by computer screen with adjustable intensity
of light. Three different intensity of white, simple stimulus was used: 21.4
cd/m2, 10.5 cd/m2 and 2 cd/m2. Than we
performed different type of stimuli with different intensity: white-simple
stimulus (WSS) (21.4cd/m2), red stimulus (RS) (3.9cd/m2)
and complex-checkerboard stimulus (CCS) (10.5cd/m2). The
amplitudes of VEFR were further statistically evaluated by ANOVA for repeated
measures and paired t-test. Results: The results of repeated measures ANOVA for
different intensities of WSS did not show significant differences between
measurements (p=0.56). The ANOVA of repeated measures for different type of
stimuli showed significant differences between measurements (p=0.001). Paired
t-test showed significant differences between WSS and CCS (p=0.002 ), WSS and
RS (p=0.010) as well as red and CCS (p=0.044). MAP and Et-CO2 did
not change significantly during stimulation. Conclusions: We concluded that CVR to red stimuli is higher compared to simple-white stimuli, however, it is lower compared to complex stimuli. |
|
P091 |
Effects of nitrous oxide
on cerebral autoregulation during Sevoflurane anaesthesia. A transcranial
Doppler Study Iacopino DG, Conti A, Battaglia C,
Santamaria L, Tomasello F. Neurosurgical Clinic and Anesthesiological
Service. University of Messina. Italy. Background.
Cerebral autoregulation is a homeostatic mechanisms that minimizes deviations
in cerebral blood flow when cerebral perfusion pressure changes. It acts
through vasomotor effectors that control cerebrovascular resistance (CVR). A
number of studies have demonstrated an adverse effect of N2O on
cerebro-vascular hemodynamics, in both humans and animals. Increased
intracranial pressure, cerebral blood flow (CBF), cerebral metabolic rate of
oxygen (CMRO2) and reduced autoregulation indexes have been
reported, but their magnitude is still debated. Objectives. Our
study was designed to evaluate the effect of N2O on CBF and
autoregulatory indexes during N2O/Sevoflurane anesthesia in a
large prospective randomized controlled series of patients. Methods.
Patients were randomly divided in two groups of twenty on the base of the use
of N2O in the gas mixture, creating a study group (O2-N2O-SEVOFLURANE)
and a control group (O2-NITROGEN-SEVOFLURANE). The Transient
Hyperemic Response Test, using transcranial Doppler techniques, was used to
assess cerebral autoregulation. Results. The systolic flow velocity, considered as an
index of actual CBF, demonstrated a statistical significant difference
between the two groups (p= 0.0011) with an increase after introduction of N2O.
The hyperaemic response, considered as the index of autoregulatory potential,
decreased significantly in the study group after the introduction of N2O,
compared with the control group (p< 0.001). Conclusions. The increase of cerebral blood flow and the reduction of autoregulatory indices suggests caution in using N2O during Sevofluorane anesthesia, especially in patients with reduced autoregulatory reserve, and during neurosurgical interventions. |
|
P092 |
L-ARGININE IMPROVES DIMINISHED CEREBRAL
CO2 REACTIVITY IN PATIENTS C. Zimmermann, R.Haberl Krankenhaus München-Harlaching, Department
of Neurology, Munich, Germany Background There
is experimental evidence that L-arginine restores diminished CO2
reactivity after mild traumatic brain injury in rats. This effect is believed
to be mediated by L-arginine derived nitric oxide being a permissive
substrate for CO2 reactivity. To verify these findings and
underline a possible beneficial effect of L-arginine in clinical situations
we have tested the influence of L-arginine on CO2 reactivity of
the cerebral vessels in human subjects. Methods 42
patients with mild signs of arteriosclerosis without having extra- or
intracranial stenoses were examined by bilateral transcranial
Dopplersonography of the right and left middle cerebral artery. Vasomotor
reserve (VMR) was tested by 1min hyperventilation followed by a 3min inhalation
of 5%CO2. Examination was performed twice, once before and once
after infusion of 30g L-arginine over 30 min and results were compared before
and after administration of L-arginine. Results There
was no difference of right and left side vasoreactivity, initial mean
vasomotor reactivity (VMR) of 42 patients was 51 ± 14%. In
patients with reduced VMR (< 50%) in the first examination (42 ± 8%, n=22)
vasoreactivity was significantly increased after infusion of L-arginine (52 ± 14%,
p=0.005). In patients with normal CO2 reactivity (> 50%, n=20)
values did not change after infusion of L-arginine (59 ± 8% before
versus 59 ± 13% after L-arginine). Conclusions Our data supports the hypothesis that L-arginine is able to improve impaired cerebral CO2 reactivity also in patients when they have slight disturbances of vasomotor reactivity. |
|
P093 |
CEREBRAL VASOMOTOR INSTABILITY CAUSED
BY THE DECREASE OF VESSELS WALL’S TONE G.Baltgaile , T.Timofejeva Latvian Medical Academy, Riga, Latvia Autonomic regulation of haemodynamic
involves the regulation of vessels wall’s tone and is examined as a clinical
routine tests and dopplerographical tests for autoregulation. Sonologically
detected vasomotor instability manifested as an abnormal blood flow
velocity’s distribution in cerebral arteries without certain signs of
arterial wall pathology is often defined in young people with symptoms of
autonomic nervous system dysfunction. To define the role of vessel wall’s tone
in such processes 25 healthy subjects and 73 patients (19-38 y.o.) with
autonomic nervous system dysfunction had been examined clinically and
sonologically. Carotidal arterial wall dilatation in diastole-systole had
been measured used M-mode (cardiac regime) as well as routine distance
measurement by linear probes 7-12Mhz and 4-7Mhz (HDI-5000, ATL). Other pre-
and cerebral vessels have been examined usual way. The most characteristic ultrasonological
feature in patients with autonomic nervous system dysfunction was decrease of
precerebral and cerebral vessels wall’s tone detected as: 1) the increase of
carotid artery’s wall dilatation during diastole (mean on 0,07+-0,03 cm) with
the increase of pulsative index (mean 1,96+=0,67); 2) the flow acceleration
in normal sized or dilated middle cerebral arteries (Vmax +=s/d 136+=15,6
cm/sec) with the presence of vascular noises in cerebral arteries (in 38% of
cases on arterial branching); 3) the dilatation of vertebral and basal veins (in 24% of patients) with the venous flow’s acceleration in a varying degree ( in 68% of patients). |
|
P094 |
TCD FINDING OF BASILAR OCCLUSION IN
PATIENTS AFFECTED BY MILD ASPECIFIC SYMPTOMS WITHOUT STROKE. D.Bosone , S. Marcheselli, A. Cavallini, G.Giardini, G.
Micieli. Neurovascular Unit, "C.Mondino"
Foundation, University of Pavia. Italy Background: Basilar artery occlusion (BAO) is known as a
cause of dramatic ischemic stroke presenting with well described clinical
syndromes (1) and characterised by a very poor outcome and no effective
treatment. The introduction of early intra-arterial fibrinolysis has provide
a stimulus to develop non invasive diagnostic tools like Transcranial
Doppler. The chance to investigate non invasively and within few minutes a
large number of patients is now disclosing new correlation between clinical
symptoms and vascular status. In particular there are few data concerning
premonitory symptoms of BAO, not associated with stroke (2). We describe two
cases in which BAO Doppler finding was surprisingly associated with mild and
non-specific clinical symptoms. Case1: A men (50 years old) was admitted at the end of 2001 to our hospital
for a 10 minutes lasting episode of vertigo and headache in orthostatic
position. He was a smoker, affected by arterial hypertension. CT scan was
normal. A routine TCD examination disclosed a suspect of BAO, confirmed with
MRA. The patient received anticoagulant therapy. Two months later TCD still
confirmed occlusion of basilar artery. The patients up to date is still alive
and free of symptoms. Case2: A woman (60 years old) was admitted in
2000 for two year-lasting vertigo and more recent transient episodes of
ocular flashes and palpebral ptosis. Personal history was positive for
arterial hypertension. CT scan was normal. A routine TCD suggested BAO,
confirmed by arterial angiography. This patient received anticoagulant
therapy too. One year later the basilar artery was still occluded but the
patient was alive and free of symptoms. Conclusions: TCD helped to discover BAO and to prevent very probable serious stroke in patients with underestimated premonitory symptoms. |
|
P095 |
INVESTIGATION OF CEREBROVASCULAR
REACTIVITY IN MIGRAINE WITH AURA AND WITHOUT AURA J. Petrova, E. Vassileva, P. Shotekov University Hospital
"Alexandrovska", Sofia, Bulgaria Background: Migraine pain is usualy ascribed to changes of
blood flow of transcranial arteries. In this study we have investigated
cerebrovascular reactivity in migraine patients with aura (MWA) and without
aura (MWOA). Methods: By using transcranial Doppler ultrasonography we
studied the changes of flow velocity after Valsalva, dynamic orthostatic
tests and Nytroglicerine test. 15 patients with MWA and 15 with MWOA.
Inclusion criteria were: 1) Age >18 years, 2) Migraine patients out of
attacks, 3) Adequate transtemporal visualization of the MCA, 4) Non-smokers. Results: The group with aura had higher baseline systolic
velocity and lower distolic velocity than the group without aura. The
response to Valsalva and Nitroglicerine tests had significantly higher values
at patients with aura than the group without aura. The group with aura had significantly
lower diastolic velocity at Valsalva, Orthostatic and Nitroglicerin tests
than this without aura. Conclusions: These data shows that the cerebrovascular failures are of different type in migraine patients with aura and without aura. |
|
P096 |
Cerebral Autoregulation in Patients
with Intracranial Aneurysms after Anesthesia Induction V.B. Semenyutin, V.A. Aliev, V.V.
Alexeev, G.A. Assaturyan, S.K. Sergienko Russian Polenov Neurosurgical Institute,
St. Petersburg, Russia Background: An effect of different types of anesthesia on
cerebral autoregulation (CA) has been described in volunteers and patients,
subject to orthopedic operations. However, these data do not permit to give
reliable assessment of anesthesia induction (AI) and its effect on CA in patients
with intracranial aneurysms (IA). Methods: We examined 25 patients, who underwent surgical
interventions for IA. They were divided into two groups. The 1st
group included 13 patients, operated in a "cold" period of SAH; the
2nd group comprised 12 cases, operated in its acute period (grade
ll-lll, WFNS scale). A combination of arduan, propophol and clophelin was
used for AI. CA was assessed with the help of a cuff test. Systemic blood
pressure (SAP) in a radial artery was registered continuously by the M-34
Mingograph (Siemens). Blood flow velocity (BFV) in both middle cerebral
arteries was recorded, using the Multi-Dop X (DWL) system. Results: Before AI patients of the 1st group
had SBP equal to 96.7+7.2 mm Hg; a rate of regulation (RoR) on the
right and left was 20.9+2.0%/s and 20.5+1.7%/s respectively.
These data correspond to normal values, determined earlier. SBP in the 2nd
group was 97.1+9.2 mm Hg; RoR on the left and right 13.1+2.3%/s
and 13.5+2.1%/s respectively. These indices were considerably smaller
(p<0.001) and reflected CA disorders. AI was followed by decrease both SBP
and BFV up to 31.9+8.5% and 38.7+10.1% respectively in 10
patients of the 1st group and 8 patients of the 2nd
group (there was no reliable difference in changes of BFV and RoR on the left
and right; thus, all the values presented below, are referred to the side of
their maximum decrease). At the same time SBP in 3 patients of the 1st
group and 4 patients of the 2nd group fell to 18.4+4.1%
after AI; BFV decreased up to 20.9+7.8.%. After AI and during normal
ventilation ROR of all patients of the 1st group was 13.7+1.2%/s,
it was equal to 9.5+1.3%/s in all patients of the 2nd
group. As for hyperventilation, there was a significant increase of ROR
(p<0.001) both in patients of the 1st (17.5+1.9%/s) and
2nd groups (13.5+3.4%/s). Conclusion: Anesthesia induction in ICA causes decrease of RoR in patients, operated in "cold" and acute periods of SAH. |
|
P097 |
STUDY THE EFFECT OF CARBON DIOXIDE
PNEUMOPERITONEUM ON THE CEREBRAL BLOOD FLOW VELOCITY USING TRANS-CRANIAL
DOPPLER DURING LAPAROSCOPIC SURGERY Chunfeng Liu, Hong Xie, Hao-rong Wu, et al. Department of
Neurology,Second Affiliated Hospital of Suzhou University,Suzhou,China Background:Recently laparoscopic surgery has been widely used
in the clinic particuly in elderly patients,but it is not reported that
carbon dioxide pneumoperitoneum effects on the cerebral circulation during
operation. Methods: Use the TCD of biprobe(EME 2020) to monitor
dynamically the MCA’s mean cerebral blood flow velocity and pulsatility
indexes through the temporal windons,also measurements of blood pressure in
19 patients with cholelithiasis underwent laparoscopic surgery. Results: The mean cerebral blood flow velocity of MCA has no
change,even though the pulsatility indexes decreases and blood pressure
increases after carbon dioxide inflation of the peritoneum,during the
laparoscopic operative procedure.When the operation was over,the pulsatility
index and blood pressure soon became normal,especially the diastolic pressure
became stable. Conclusions: carbon dioxide pneumoperitoneum will not do any harm to the cerebral blood flow while operation clone with laparoscopiy. |
|
P098 |
CHANGES IN CEREBROVASCULAR RESISTANCE
AFTER HEAD-UP TILT IN COMPENSATED AND DECOMPENSATED ORTHOSTATIC HYPOTENSION
PATIENTS H.Y. Hsu, H.H. Hu, Y.C. Chen, P.Y. Wang Section of Neurology, Taichung Veterans
General Hospital, Taiwan Background: Patients with decompensated orthostatic
hypotension(OH) had decreased cerebral blood flow on head-up tilt (HUT).
Patients with compensated OH had normal cerebral blood flow despite postural
hypotension. Loss of cerebrovascular reserve might result in the difference.
We tried to investigate the pathogenesis of decompensated cerebral flow
change. Methods: Totally, 36 subjects were study. There were 12
subjects in each group (control, compensated & decompensated OH). Radial
blood pressure(ABP) (tonometer, Colin 7000) and middle cerebral artery flow
velocity (CBFV) (transcranial doppler, Nicolet, EME TC4040) were recorded
continuously. Both signals were digitalized and stored into an IMB compatible
PC. Critical closing pressure (CrCP) and resisatnce-area product (RAP) were
calculated from 2 stable segments (before and after HUT respectively) of CBFV
and ABP signals using beat-to-beat linear regression method. Non-parametric
Kruskal-Wallis test and Mann-Whitney test were used to compare the change in
CrCP and percentage change of RAP among groups. Results: The reduction of ABP was similar between
compensated OH and decompensated OH groups. The decompensated OH group had
significant reduction in mCBFV( 12.6±2.6 cm/sec,p<0.001). The change in
CrCP was not different among 3 groups (p=0.597). The percentage reduction of
RAP after HUT was significantly larger in the compensated group (35.4±4.9%,
p=0.007). However, the percentage change of RAP was not significant different
between control (14.3±7.9%)and decompensated group (24.1±7.1%). Conclusions: The limited cerebrovascular reserve was insufficient to cope with marked ABP change on HUT in patients with decompensated OH. RAP was a useful parameter in assessing cerebrovascular reactivity. |
|
P099 |
SMALL VS LARGE-VESSEL STROKE: IS
CEREBRAL VASOMOTOR REACTIVITY DIFFERENT? ISRAELI-TURKISH COLLABORATIVE STUDY A.Y. Gur,¹ D. Gücüyener,² N. Üzüner,² G.
Özdemir,² A.D. Korczyn,¹ N.M. Bornstein¹, Departments of Neurology,
Tel Aviv University, Tel Aviv, Israel,¹ Osmangazi University, Eskisehir,
Turkey Background: Both small- and large-vessel strokes are
well-known types of cerebrovascular ischemic events. The cerebral hemodynamic
features of patients after different types of stroke are still poorly
defined. Our study aimed to assess and compare cerebral vasomotor reactivity
(VMR) in patients with small- (SV) and large-vessel (LV) strokes. Methods: We assessed VMR using transcranial Doppler and the
Diamox test (1 g acetazolamide i.v.) in 20 post-stroke patients. The percent
difference between blood flow velocities in the middle cerebral arteries
before and after the Diamox test was defined as VMR%. All patients underwent
carotid duplex to exclude severe carotid occlusive disease as a factor which
might affect VMR. Lacunar or single large artery infarcts were confirmed by
CT and/or MRI in all patients. The patients were divided into those with SV
(group 1) and LV (group 2) strokes; their VMR% values were compared using the
ANOVA test. Results: Group 1 (n=10, 7 men, mean age 64.2±19.5 years)
and group 2 (n=10, 5 men, mean age 68.2±18.5) were well matched for common
vascular risk factors and timing after stroke (3-36 months). The mean VMR%
was 43.7±29.5% for group 1 and 40.8±24.8% for group 2. There was no statistically
significant difference between the VMR% of the two groups (P=0.2). Conclusions: Our data suggest a similar VMR in patients with SV and LV types of ischemic stroke. While they are clearly different in terms of etiology, clinical features and prognosis, both types have comparable hemodynamic patterns. |
|
P100 |
KINETICS OF CBF AUTOREGULATION WITH
AGEING A Pavy-Le Traon, M C Costes-Salon, G.Geraud, V Larrue *Neurology department, Rangueil Hospital,
1 Avenue Jean Poulhes, 31 054 TOULOUSE CEDEX, France Background and objectives Cerebral autoregulation can be defined as the
homeostatic mechanism that minimises changes in cerebral blood flow (CBF) in
response to changing cerebral perfusion pressure. Ageing is associated with
cardio-vascular changes including more frequent orthostatic hypotension but
the effects of normal ageing on cerebral autoregulation capacity are not well
known. The objectives of our study were to assess changes in kinetics of CBF
autoregulation with age.3. Methods Continuous monitoring of middle cerebral artery
(MCA) blood flow velocity (BFV) by TCD and beat-to-beat blood pressure (BP)
by Finapres was performed during the sharp physiological decrease in blood
pressure induced by standing up rapidly after two minutes in squatting
position in three groups of male and female healthy volunteers (14/group) of
different ages (Group 1: 30+/-6 y ; Group 2: 44+/-3y ; Group 3: 63+/-6 y). To
assess the effects of BP decrease on CBFV, an index (CR) was calculated by
dividing mean BP by mean MCA BFV. Rate of regulation was determined as
normalised changes in CR per second during the blood pressure drop. Results In squatting position, mean BP was significantly
higher in Group 3; mean MCA BFV did not differ in the three groups. The mean
decrease in MBP induced by standing up tended to be greater in group 3 (-40%)
than in group 1 (-31%) (P=0.06) as well as the mean decrease in mean BFV
(-34% vs -23%) (P=0.04).In response to the larger drop in BP, the rate
of autoregulation was larger in group 3. The time to obtain maximum
vasodilation (in sec) did not differ with age (group 1 : 11.3+/-2.5 ; group
3: 12.7+/-4.8). Conclusion This study suggests that the kinetics of cerebral autoregulation is maintained with normal ageing. |
|
P101 |
FRACTAL ANALYSIS OF MCA FLOW VELOCITY FLUCTUATIONS IN PATIENTS WITH VASOMOTORIC DISTURBANCES M.Glaubic-Latka*, M.Latka**, D.Latka*, B. J. West*** *Dept.of Neurology, Dept.of Neurosurgery,
Opole, POLAND **Physics Department, University of
Technology, Wroclaw, POLAND ***Mathematic Division, Army Research Office, NC, USA Background: Many physiological signals fluctuate in apparently
irregular and complex manner. However, the fractal analysis of these
fluctuations often reveal the existence of long-range correlations in healthy
subjects. The breakdown of these correlations may be caused by disease or
aging. In the same way, the authors decided to establish how the normal
cerebral blood flow autoregulation in healthy subjects is reflected in the
fractal properties of MCA flow velocity fluctuations and whether these
properties may be altered in pathological states. Method: We studied the MCA flow velocity (MCAfv) in human
using TCD (DWL Multi-Dop T). The 2-MHz Doppler probes were placed over the
temporal windows and fixed at a constant angle and position. The measurements
were taken continuously for approximately 2 hours at supine rest. The study
comprised the healthy individuals and the subjects with presumed vasomotoric
disturbances. The fractal analysis of the time series of
the axial flow velocity fluctuations averaged over a cardiac beat interval
was performed. The Hurst exponent which determines the monofractal properties
as well as the singularity spectrum which characterizes the multifractal
properties were calculated. Results: The time series of the axial flow velocity averaged
over a cardiac beat interval exhibit clear multifractal properties for
healthy subjects. We observe a loss of multifractality for some subjects with
vasomotoric disturbances. Conclusion: The fractal analysis of MCA blood velocity may be useful in diagnostics of vasomotoric disturbances. We are currently investigating the fractal properties of the MCAfv time series in migraineurs. |
|
P102 |
THE POSSIBLE MECHANISMS OF THE CEREBRAL
BLOOD FLOW CHANGES IN HYPOKINESIA CONDITION A.H. Manukyan Yerevan State Medical University, Yerevan,
Republic of Armenia Background: To determine the possible mechanisms of the
changes of the local cerebral blood flow (lCBF) in early (15 day) hypokinesia
(HK) condition and to establish the possible ways of a correction of these
changes. Previous works show that a decrease of lCBF may be mediated by the
different factors such as the vascular sensitivity increase to the endogenous
vasoconstrictor substances, the changes in aggregation and metabolic
intensity. Methods: lCBF was measured by laser Doppler flowmetry in
rats being in early HK condition. The isotonic contractions of the isolated
grafts of the thoracic aorta of rats were registered with the help of the
apparatus "Isotoche Messeinrichtung" (Germany) on the apparatus of
registration "Hitachi" (Japan). The thrombocyte aggregation was
investigated by classic nephelometric method on aggregometer
"Payton" (USA). Results: In early HK the intensification of the lipid
peroxidation processes are observed. Some products of lipid degradation have
a vasoconstrictor activity. One of these substances is malonic dialdehyde
(MDA). It results in the decrease in lCBF in early HK. The reason of lCBF
decrease may be the vascular sensitivity increase to the vasoconstrictor substances
that is manifested by the increase of the isolated graft contractility to
MDA. The decrease of lCBF may be also mediated by the strengthening of
thrombocyte aggregation caused by MDA. In early HK both atropine and a
-tocopherol acetate diminish the drop of lCBF. Besides GABA-ergic remedies
render a positive influence on the lCBF changes that is possibly explained by
the antioxidant action of GABA-mimetics as well as the antagonism with MDA in
regard to GABA receptors. Conclusion: The worsening of cerebral blood flow in HK may be the result of an influence of some products of lipid degradation, accumulation of which is observed in an intensification of the lipid peroxidation processes, on the cerebral vessels and an aggregating ability of thrombocytes. In HK condition the substances with the antioxidant and antiaggregating activities as well as the compounds with GABA-ergic and M-cholinolytic properties can compensate the infringements of the cerebral blood flow. |
|
P103 |
CEREBROVASCULAR RESISTANCE DURING ACUTE
OSMOTIC BLOOD-BRAIN BARRIER DISRUPTION JM McGregor, ME Miner, S Bell The Ohio State University, Columbus, Ohio,
USA BACKGROUND: Cerebral hemodynamics and resistance during osmotic blood brain barrier disruption (BBBD) remain to be fully elucidated. The effects of this method of drug delivery on Transcranial Doppler velocity parameters were studied in our patient population undergoing disruption. METHODS: Continuous TCD monitoring was performed on patients undergoing BBBD for delivery of chemotherapy in the treatment of their brain tumor (glioblastoma, anaplastic astocytoma, CNS lymphoma). Anterior circulation disruptions were studied. Per protocol, each patient was anestheized, intubated, and stabilized for BP, HR, and end-tidal CO2 immediately prior to disruption. Continuous TCD monitoring of the ipsilateral MCA was performed (depth 56-48cm) and recordings of mean velocity(Vm), systolic velocity(Vs), diastolic velocity(Vd), pulsatility index(PI), and resistance index(RI) were made. Values from infusion of mannitol to completion of chemotherapy (15-20min) were compared to pre-disruption baselines. CT scans post disruption classified the degree of disruption and were compared to changes in TCD parameters. RESULTS: At BBBD onset, velocity measures increased by over
150%. Average time to maximum velocities was 2.2 – 2.9 minutes; Average times
back to baseline was 15-17 minutes. Three resistance patterns were noted: a
decrease in resistance that slowly returned to baseline, a bi-phasic pattern
of a drop then elevation of resistance, and a pattern of prolonged elevation.
CONCLUSIONS: Multiple physiologic alterations are at work
during osmotic BBBD, and the effects on vascular resistance are somewhat
variable. The BBBD that show patterns of decreased resistance are associated
with CT scans showing greater degree of disruption.
|
|
P104 |
THREE DIMENSIONAL ULTRASOUND OF THE
VERTEBROBASILAR SYSTEM Zavoreo I, Kesic MJ, Lovrencic-Huzjan A, Roje Bedekovic M,
Demarin V Neurology Depr University Hospital
"Sestre milosrdnice", Zagreb, Croatia Background: Transcranial color-coded sonography (TCCS) is used
for evaluation of the vertebrobasilar (VB) system. In most indviduals the
origin of the basilar artery (BA) can not be visualised due to unfavourable
angle of the vertebral arteries (VA) junction or unfavourable angle of
insonation. All three vessels can be rearly visualised at the same time.
Three-dimensional ultrasound (3D US) enables reconstruction from transcranial
power Doppler (PD) imaging of the VB system. Methods: We tried to display the 3D images of the
intracranial parts of the VA and BA. Interactive 3D imaging software was
integrated into an ultrasound platform (Aloka Prosound 5500). Data aquisition
was performed using 2,5 MHz sector transducer, freehanded in a fixed length
of time (10 seconds), allowing PD sonography. The images were postprocessed
(TomTec imaging system). 12 patients were investigated in order to visualise
all three vessels at the time, and to calculate the angle between each pair
of vessels, according to the direction of the blood vessels. Results: In TCCS was not possible to obtain all three
vessels at the time in niether patient while in PD mode we were able to
obtain all three vessels at the time in 2/12 patients. 3D PD enabled
visualization of all three vessels at the time in 9/12 patients (1 VA was
occluded-diagnose was suspected by 3D PD and confirmed by angiography, in 2
cases suboptimal suboccipital window ). The angle between VA could be obtained
in 9/12 patients. In 2 patients the the angle between VA and BA origin
couldn’t be adequately visualised, but mathematical reconstruction according
to the direction of the blood vessels was possible. Conclusions: 3D US enabled visualization of the VB junction, and in the cases of inadequate visualisation of the BA origin mathematically reconstruction was possible. |
|
P105 |
GLOBAL CEREBRAL CIRCULATION TIME (CCT)
MEASURED BY EXTRACRANIAL DOPPLER IN PATIENTS WITH DEMENTIA S. Schreiber, F. Doepp, E. Spruth, J.M. Valdueza Dept. of Neurology, University Hospital
Charité, Berlin, Germany Background: Differentiation of vascular dementia (VD) from non
vascular dementia (NVD) is a difficult clinical task. Microangiopathy as one
of the main causes for VD leads to vessel rarification and a subsequent
prolongation of CCT. Assessment of a global CCT might allow a clear
differenttiation between VD and NVD. Methods: Global CCT was assessed as the extracranial time
delay of an echocontrast bolus arrival (Levovist ®) between the distal
internal carotid artery and the internal jugular vein. 27 VD patients, 9 NVD
patients and 28 healthy age matched controls were studied. Results: Median CCT was 8.8 sec in the VD group (mean± SD: 9.0 ± 2.4 sec),
8.0 sec in the NVD group (8.2± 1.8 sec) and 6.6 sec in controls (6.9± 1.1 sec).
Statistical analysis revealed a significant difference among the group
medians (Nonparametric ANOVA, p=0.001, KW=13.9). Post test analysis showed a
significant difference between controls and VD only (Dunn, p<0.05) but not
between VD and NVD. Discussion: VD patients show a significantly prolonged global CCT when compared to healthy controls, supporting the hypothesis of increased blood flow resistancy in microvasculopathy. In contrast to previous reports also the NVD patients seem to have an altered cerebral circulation time which reduces the power of the test for the differentiation between patients with VD and NVD. Further inclusion of patients should allow to perform sensitivity and specificity analysis for the proposed test. |
|
P106 |
COMPARISON OF PLATELET FUNCTION
ANALYSIS; PLATELET AGGREGATION TESTS AND MICROEMBOLUS DETECTION BY
TRANSCRANIAL DOPPLER ULTRASOUND IN IDENTIFICATION OF ASA-NONRESPONDER S.Guhr, T.Blaser, K.Hofmann, G.Lutze, M.Goertler Department of Neurology,
Otto-von-Guericke-University Magdeburg, Germany Background: Conventional platelet aggregation tests have failed
to detect patients who are at increased risk for a recurrent stroke even
under secondary prevention with ASA (ASA-nonresponder). Laboratory testing by
the Platelet Function Analyser (PFA) 100 might be an alternative. In
contrast, cessation of embolic signals after antithrombotic prevention in
patients with arterio-embolic stroke was associated with a reduced risk of
stroke recurrence. Methods: Twenty patients (12 men, mean age 63.5 years) with
a recently (<30 days) symptomatic stenosis of the internal carotid or
middle cerebral artery underwent collagen induced platelet aggregation test
as well as PFA 100 testing just before and 11 days (mean) after start of a
secondary prevention with ASA. Eleven patients additionally underwent
transcranial Doppler (TCD) for the detection of embolic signals. Results: After ASA, 19 patients showed pathologic
aggregation test (maximal aggregation <82%) as well as increased PFA
values (> 165 s). Of the 11 patients who underwent TCD, 5 initially were
signals positive ( mean 23/h; range 1 to 37), who all demonstrated laboratory
response to ASA by both, platelet aggregation and PFA 100 test. Conclusion: ASA response at PFA 100 testing is not related to cessation of embolic signals. As the latter has shown to be related to stroke recurrence, PFA 100 tsting might not predict clinically relevant ASA response. |
|
P107 |
Reduced risk of recurrent arterio-embolic
TIA and stroke is related to cessation of embolic signals after
antithrombotic prevention M. goertler, T. Blaser, S. Krueger,
K. Hofmann, S. Guhr, CW. Wallesch Department of Neurology, Otto-von-Guericke
University Magdeburg, Germany Background: We aimed to determine the predictive value of
decreased embolic signals on the risk of early stroke recurrence after the
initiation of an antithrombotic secondary prevention in patients with recent
arterio-embolic stroke. Methods: Eighty six consecutive patients with a
non-disabling arterio-embolic ischemic event within the last 30 days and a
medium- or high-grade stenosis of the ipsilateral carotid or middle cerebral
artery underwent one-hour transcranial Doppler monitoring at admission. Then
antithrombotic secondary prevention was started. Patients who had embolic
signals underwent a second monitoring within 4 days. All patients were
followed up within the next 6 weeks. Results: Embolic signals were detected at admission, 5.4
days (mean) after the initial event in 44 patients, 25 were positive for
embolic signals also at the second monitoring, in 19 signals had ceased. 42
patients, without embolic signals already at admission, served as controls.
During follow-up, 6 ischemic events occurred in 25 patients with persisting
embolic signals but none in 19 patients in whom signals had ceased by the
second monitoring. One patient of the control group suffered a TIA.
Persistence of embolic signals was an independent predictor of a recurrent
ischemia (adjusted odds ratio: 37.0; 95% CI: 3.5-333; p<0.003). Cessation
and decrease of embolic signals was associated with the administration of
antiplatelet agents but not with anticoagulation with intravenous heparin
(p<0.001). Conclusions: Rapid cessation of embolic signals detected in patients with recently symptomatic arterial stenosis decreases elevated risk of an early ischemic recurrence. Effect of antithrombotic agents on embolic signals might serv |