Cerebral Arteries In Patients Research Articles

Effect of Transdermal Nitroglycerine on Doppler Velocity Waveforms of the Uterine, Umbilical and Fetal Middle Cerebral Arteries in Patients with Chronic Placental Insufficiency: A Prospective RCT.

Increase in Nitric Oxide (NO) may be important in vascular adaptation needed to accommodate increased uteroplacental blood flow as pregnancy advances. Hence, in certain conditions like Pregnancy Induced Hypertension (PIH) and Fetal Growth Restriction (FGR), NO donors may play an effective role in increasing uteroplacental perfusion. Transdermal route appears to be a safe and effective route. To evaluate the effect of nitroglycerine patch on Doppler velocity waveforms of the uterine, umbilical and fetal middle cerebral arteries in patients with chronic placental insufficiency. A prospective randomized controlled clinical trial was conducted on eighty consecutive pregnant women with FGR with or without PIH and having evidence of altered waveform velocimetry in uterine, umbilical and fetal middle cerebral artery. They were divided into two groups- study and control group. Transdermal nitroglycerine patch (10 mg per 24 hours) was applied in study group for three consecutive days. Changes in various Doppler indices were noted after three days of patch application and compared between the two groups. Analysis was carried out using SPSS (Statistical Package for Social Studies) for Windows version 20.0 and online GraphPad software (Prism 5 for Windows) version 5.01. A significant fall in the systolic and diastolic ratio (S/D), Pulsatility Index (PI) and Resistivity Index (RI) of the uterine (3.07±0.52, 1.04±0.14 and 0.54±0.10 respectively, p<0.001) and umbilical artery (3.73±3.30, 1.18±0.21and 0.64±0.07 respectively, p<0.001) was noted after three days of patch application. No such significant change was observed in the middle cerebral artery indices. The therapeutic approach of NO donor administration via transdermal route in pregnant patients with chronic placental insufficiency, apparently improved both maternal and fetoplacental haemodynamics, thus may help in improving perinatal outcome.

Multiple factor analysis of symptomatic intracranial arterial stenosis

Objective To discuss the correlation among intracranial arterial stenosis and its risk factors. Methods A total of 486 patients with transient ischemic attack (TIA) or ischemic cerebral infarction were examined using color doppler flow imaging (CDFI) and transcranial doppler ultrosonography (TCD).According to the degrees of extracranial arterial stenosis, patients with mild-to-moderate extracranial stenosis were classified into group A (435 cases) while those with constant severe stenosis or occlusion were classified into group B (51 cases).The differences between the two groups of risk factors were compared, and the multi-factor logistic regression analysis of risk factors associated with moderately severe intracranial arterial stenosis was performed. Results ① The risk factors that were significantly associated with intracranial arterial stenosis included age ( P =0.034) and gender ( P =0.044).② Intracranial artery stenosis was observed in both anterior and posterior cerebral arteries in patients with hypertension, diabetes, and coronary heart disease respectively ( P P =0.000), with a higher proportion of men ( P =0.037), and the intracranial arterial stenosis degrees were significantly higher ( P =0.013).â'£ Multi-factor logistic regression analysis showed that diabetes is a risk factor for moderately severe intracranial arterial stenosis ( P P =0.012). Conclusions Age, gender, hypertension, diabetes, coronary heart disease, and smoking are risk factors for the distribution of intracranial arterial stenosis.The degrees of intracranial arterial stenosis are related with extracranial arterial stenosis.Diabetes is a risk factor for moderately severe intracranial arterial stenosis while hyperlipidemia is a protective factor.

Predictive Factors for the Spontaneous Recanalization of Large and Middle Cerebral Arteries after Acute Occlusion

This study aims to investigate the predictive factors for the spontaneous recanalization of occluded arteries in patients with acute ischemic stroke. A total of 139 patients with consecutive acute ischemic stroke were enrolled from June 2010 to June 2013. The clinical and biochemical parameters were measured in each participant. Occlusion and recanalization of the carotid artery, the middle cerebral artery, and the vertebral and basilar arteries were identified by using computed tomographic angiography or digital subtraction angiography. Among the 139 patients, 23 showed spontaneous recanalization, whereas 116 did not. In the patients with spontaneous recanalization, the proportion of atrial fibrillation was significantly lower (0% versus 29.31%, P= .01), whereas the proportion of stage 3 hypertension was significantly higher (60.87% versus 32.76%, P= .01) than that of those without recanalization. Logistic regression analysis showed that the proportion of atrial fibrillation was negatively (odds ratio [OR]: .117, 95% confidence interval [CI]: .015-.918, P= .04) associated with spontaneous recanalization, whereas the proportion of stage 3 hypertension was positively (OR: 4.316, 95% CI: 1.533-12.154, P= .01) associated with it. Atrial fibrillation is associated with reduced spontaneous recanalization of the large and middle cerebral arteries in patients after acute ischemic stroke-induced occlusion, whereas stage 3 hypertension may contribute to the promotion of the recanalization.

Relationship between deep medullary veins in susceptibility-weighted imaging and ipsilateral cerebrovascular reactivity of middle cerebral artery in patients with ischemic stroke.

Deep cerebral veins have been recently associated with the severity of hemodynamic impairment in moyamoya disease. The aim of the current study was to determine the correlation of deep medullary veins (DMVs) in susceptibility-weighted imaging (SWI) with ipsilateral cerebrovascular reactivity (CVR) of and anterior cecebrocervical artery stenosis in patients with ischemic stroke. Patients with unilateral TIA or infarction who underwent 3.0 T magnetic resonance imaging SWI, digital subtraction angiography and transcranial Doppler with CO2 stimulation within the first 7 days of hospitalization were retrospectively selected. CVR and stenosis of anterior cerebrocervical arteries were compared between different DMVs stages in symptomatic hemispheres (SHs) and asymptomatic hemispheres (AHs). A total of 61 patients were subsequently included in the present study. A univariate analysis was conducted and results for age (PAHs=0.004, PSHs=0.006), hypertension (PAHs=0.008, PSHs=0.020), current smoking (PAHs=0.006, PSHs=0.021), CVR (PAHs=0.000, PSHs=0.000), and artery stenosis (PAHs=0.000, PSHs=0.000) were obtained. The results suggested statistically significant differences between DMVs grades in SHs and AHs. A subsequent multivariate analysis revealed that CVR (ORAHs=0.925, 95% CIAHs: 0.873–0.981; ORSHs=0.945, 95% CISHs: 0.896–0.996), and artery stenosis (ORAH=3.147, 95% CIAH: 1.010–9.806; ORSHs=2.882, 95% CISHs: 1.017–8.166) were independent risk factors of DMVs. In conclusion, 3.0 T SWI was useful in detecting the DMVs around the lateral ventricle in patients with atherosclerotic ischemic stroke. CVR and stenosis of anterior cerebrocervical arteries were independent risk factors for ipsilateral DMVs in SHs and AHs.

Historical Perspective and the Role of Endoscopy in Intracranial Aneurysm Surgery

The surgical treatment of cerebral aneurysms has a relatively recent history, dating to the 1930s, and it is still an evolving field. In 1931, Norman Dott performed the first direct treatment of a ruptured intracranial aneurysm successfully packing the aneurysm and internal carotid artery (ICA) with muscle. Dott was also credited with introducing cervical carotid ligation for the treatment of ruptured intracranial aneurysms in 1933. The first successful description of an intracranial aneurysm clipping was in 1937, when Walter Dandy used a silver clip to treat a ruptured ICA aneurysm. Dutton and Selverstone introduced wrapping as a routine method for treating intracranial aneurysms that were difficult or impossible to clip. Suboptimal results in the 1950s led to the reappraisal of the indirect method, which was first described by Dott. Valentine Logue was responsible for its popularization advocating the proximal ligation of the dominant anterior cerebral artery in patients with ruptured anterior communicating aneurysms. Despite the technical advances, the morbidity resulting from direct treatment of intracranial aneurysms was still substantial. The introduction of the microscope to neurosurgery in the 1960s had a tremendous impact on the results of aneurysm surgery. In addition to improving the results of aneurysm surgery by experienced surgeons, the microscope accelerated the learning curve of young neurosurgeons who applied themselves to learning and

Accuracy of CT angiography in detection of blood supply dominance of posterior cerebral artery in patients with posterior communicating artery aneurysm.

The use of computed tomography angiography (CTA) as the sole vascular imaging study for preoperative planning for clipping of aneurysms is well described in the literature. CTA is widely available, provides quick acquisition, has low morbidity, and low cost. In this study, we describe the accuracy of CTA in determining the blood supply dominance in comparison to standard digital subtraction angiography. Sixty-six patients, with both CTAs and angiograms, were reviewed by two independent neuroradiologists. The posterior cerebral artery was determined to have dominant supply from the posterior communicating artery if it was of similar size to the P2 segment and the P1 segment was smaller by approximately 50%. If the posterior communicating artery and P1 segment were the same size, it was considered to have a dual supply. If P1 and P2 segments were the same caliber and the posterior communicating artery was smaller by 50%, it was deemed to have posterior circulation dominance. Based on the findings of our reviewers, CTA had a sensitivity and specificity of 69% and 96%, respectively, in predicting the presence of a fetal PCA. The positive predictive value was found to be 82% while a negative predictive value was estimated as 93%. A small-caliber P1 segment and large-caliber posterior communicating artery led to inaccurate interpretations of the CTAs. This study shows that one cannot accurately predict blood supply dominance of the posterior cerebral artery. Knowledge of the blood flow dominance is essential when clipping a posterior communicating artery aneurysm to avoid compromise in posterior circulation.

Histologic Analysis of Retrieved Clots in Acute Ischemic Stroke: Correlation with Stroke Etiology and Gradient-Echo MRI.

It is unclear whether clot composition analysis is helpful to predict a stroke mechanism in acute large vessel occlusion. In addition, the relationship between early vessel signs on imaging studies and clot compositions has been poorly understood. The purpose of this study was to elucidate the relationship between clot composition and stroke etiology following mechanical thrombectomy and to investigate the effect of varied clot compositions on gradient-echo MR imaging of clots. Histopathologic analysis of retrieved clots from 37 patients with acute MCA occlusion was performed. Patients underwent gradient-echo imaging before endovascular therapy. Retrieved clots underwent semiquantitative proportion analysis to quantify red blood cells, fibrin, platelets, and white blood cells by area. Correlations between clot compositions and stroke subtypes and susceptibility vessel signs on gradient-echo imaging were assessed. Stroke etiology was classified as cardioembolism in 22 patients (59.4%), large-artery atherosclerosis in 8 (21.6%), and undetermined in 7 (18.9%). The clots from cardioembolism had a significantly higher proportion of red blood cells (37.8% versus 16.9%, P = .031) and a lower proportion of fibrin (32.3% versus 48.5%, P = .044) compared with those from large-artery atherosclerosis. The proportion of red blood cells was significantly higher in clots with a susceptibility vessel sign than in those without it (48.0% versus 1.9%, P < .001), whereas the proportions of fibrin (26.4% versus 57.0%, P < .001) and platelets (22.6% versus 36.9%, P = .011) were significantly higher in clots without a susceptibility vessel sign than those with it. The histologic composition of clots retrieved from cerebral arteries in patients with acute stroke differs between those with cardioembolism and large-artery atherosclerosis. In addition, a susceptibility vessel sign on gradient-echo imaging is strongly associated with a high proportion of red blood cells and a low proportion of fibrin and platelets in retrieved clots.

Arteriovenous shunts and capillary blush as an early sign of basal ganglia infarction after successful mechanical intra-arterial thrombectomy in ischaemic stroke.

Recent studies indicate an interest in early infarct assessment, mainly using post-interventional perfusion imaging. This work evaluated two specific angiographic signs for infarct prediction in the basal ganglia immediately after successful mechanical intra-arterial thrombectomy. In this retrospective study, 57 consecutive patients (mean ± SD age 67 ± 15 years) with acute occlusion of the proximal anterior circulation who underwent mechanical thrombectomy of the M1 segment of the middle cerebral artery were included. Two separate angiographic signs, early venous drainage and capillary blush, were identified and analysed regarding their statistical significance for infarct prediction within the basal ganglia. Four patients were excluded due to parenchymal haemorrhage. Forty-four of 53 patients developed infarction of the basal ganglia. Sensitivity/specificity were 93%/27%, respectively, for the capillary blush sign and 88%/63%, respectively, for the early venous drainage sign. Combining both signs increased the sensitivity and specificity to 88% and 81%, respectively, and increased the positive predictive value to 95%. Both angiographic signs seem to predict the irreversible damage of tissue in the basal ganglia reliably despite successful recanalization of the middle cerebral artery in patients with ischaemic stroke. • Evaluation of success in neurointerventional procedures is mainly based on recanalization rates. • Two separate angiographic signs can predict infarction immediately after proximal MCA recanalization. • Combining both signs increases their specificity.

Vascular tortuosity may be related to intracranial artery atherosclerosis.

Conventional risk factors cannot explain the individual or ethnic difference in the location of cerebral atherosclerosis. Vascular geometry may play a role on this. To investigate the association between the geometrical properties of the middle cerebral artery and intracranial atherosclerosis. Stroke patients with either symptomatic middle cerebral artery or proximal internal carotid artery diseases were enrolled. The diameter, length, and tortuosity (arc-chord ratio, by percent) of the middle cerebral artery was compared between stroke patients and the age- and gender-matched healthy subjects. The geometrical property was also compared between the symptomatic middle cerebral artery and the normal-looking contralateral middle cerebral artery, and between the contralateral middle cerebral arteries in patients with symptomatic middle cerebral artery and proximal internal carotid artery diseases. One hundred seventy-seven patients (101 with middle cerebral artery disease and 76 with proximal internal carotid artery disease) were studied. Symptomatic middle cerebral artery was more tortuous (119·31 ± 16·95 vs. 112·98 ± 14·16; P = 0·009) than the contralateral middle cerebral artery. The contralateral middle cerebral artery of patients with symptomatic middle cerebral artery disease demonstrated a smaller proximal diameter (P = 0·007) and a greater vascular tortuosity than the contralateral middle cerebral artery of patients with proximal internal carotid artery disease (112·01 ± 12·25 vs. 107·46 ± 9·35; P = 0·008) and corresponding middle cerebral artery of healthy control subjects (112·01 ± 12·25 vs. 108·73 ± 9·79; P = 0·04). Young age, female, small diameter, the absence of diabetes, and high tortuosity of the contralateral middle cerebral artery were independently associated with middle cerebral artery atherosclerotic disease. High tortuosity and small diameter are related to middle cerebral artery atherosclerosis, probably by altering hemodynamics. Different degree of tortuosity may be one of the reasons for individual differences in location of cerebral atherosclerosis.

Middle cerebral arterial flow changes on transcranial color and spectral Doppler sonography in patients with increased intracranial pressure.

Intracranial pressure usually increases after severe brain injury. However, a method for noninvasive evaluation of intracranial pressure is still lacking. The purpose of this study was to explore the potential role of transcranial color Doppler sonography in assessing intracranial pressure by observing the middle cerebral artery blood flow parameters in patients with increased intracranial pressure of varying etiology. The hemodynamic changes in the middle cerebral artery in patients with varying degrees of increased intracranial pressure were investigated by transcranial color Doppler sonography in 93 patients who had emergency surgery for brain injury. Middle cerebral artery Doppler flow spectra changed regularly as intracranial pressure increased. The pulsatility index (PI) and resistive index (RI) had a significantly positive correlation with intracranial pressure (r = 0.90 and 0.89, respectively; P< .001), whereas the middle cerebral artery diastolic velocity showed a significant negative correlation with intracranial pressure (r = -0.52; P< .01). A receiver operating characteristic curve showed that the RI and PI cutoff values were 0.705 and 1.335, respectively, for predicting increased intracranial pressure, with sensitivity of 0.885 and specificity of 0.970. In addition to the PI and RI, middle cerebral artery diastolic flow velocity measurement by transcranial color Doppler sonography may also be a useful variable for evaluating intracranial pressure in patients with acute brain injury.

Cerebrolysin effects on neurological outcomes and cerebral blood flow in acute ischemic stroke.

BackgroundCerebrolysin, a brain-derived neuropeptide, has been shown to improve the neurological outcomes of stroke, but no study has demonstrated its effect on cerebral blood flow. This study aimed to determine the cerebrolysin impact on the neurological outcomes and cerebral blood flow.MethodsIn a randomized, double-blinded, placebo-controlled trial, 46 patients who had acute focal ischemic stroke were randomly assigned into two groups to receive intravenously either 30 mL of cerebrolysin diluted in normal saline daily for 10 days (n=23) or normal saline alone (n=23) adjunct to 100 mg of aspirin daily. All patients were examined using the National Institutes of Health Stroke Scale and transcranial Doppler to measure the mean flow velocity and pulsatility index (PI) of their cerebral arteries at baseline as well as on days 30, 60, and 90.ResultsThe patients’ mean age was 60±9.7 years, and 51.2% of patients were male. The National Institutes of Health Stroke Scale was significantly lower in the cerebrolysin group compared with the placebo group on day 60 (median 10, interquartile range 9–11, P=0.008) and day 90 (median 11, interquartile range 10–13.5, P=0.001). The median of PI in the right middle cerebral artery was significantly lower in the cerebrolysin group compared with the placebo group on days 30, 60, and 90 (P<0.05). One patient in the cerebrolysin group and two patients in the placebo group died before day 30 (4.3% versus 8.7%).ConclusionCerebrolysin can be useful to improve the neurological outcomes and the PI of middle cerebral artery in patients with acute focal ischemic stroke.

THE ASSESSMENT OF SPECTRAL INDICES OF HEMODYNAMICS OF EXTRA- AND INTRACRANIAL ARTERIES IN AN ACUTE SEVERE craniocerebral injury

Objective: to identify the indices of spectral Doppler intra- and extracranial arteries, as well as the diagnostic value of the indices of internal carotid arteries to assess the cerebral blood flow in an acute severe craniocerebral injury. Material and methods. The state and hemodynamic indices of the internal carotid artery (ICA) were studied in 26 patients with severe craniocerebral injuries. In 23 (88.5 %) cases ultrasonic characteristics were evaluated in the artery cerebri media (MCA). All patients (n = 26) were divided into 2 groups based on the width of the transverse displacement of the medial structures of the brain: the first group (n = 19) had dislocation ≤ 5 mm, the second group (n = 7) - offset > 5 mm. For comparative analysis and identification of correlations between the ICA and MCA hemodynamic indices, patients (n = 23) who had underwent homolateral ultrasound scanning of the arteries were picked out from subgroups 1a (n = 17) and 2a (n = 6). Results. The comparative analysis of the ICA hemodynamic parameters in the groups 1 and 2 revealed an increase in the indices of peripheral resistance in the extracranial cerebral arteries in patients with lateral dislocation more than 5 mm (p < 0.05). The study of the spectral indices of the blood flow in the homolateral arteries in the 1a group showed the presence of a close inverse correlation between the Gosling index in the ICA and Vps in MCA and significant inverse correlation between Ved and TAMX. The patients of the 2a group showed a strong direct correlation between Vps, PI in the ICA and PI in the MCA, as well as RI of both the arteries. Conclusion. The spectral indices of the ICA blood flow (Vps, PI and RI) acquire diagnostic value in the evaluation of cerebral hemodynamics in patients with dislocation of midline structures more than 5 mm.

The diameters of the A2 segment of the anterior cerebral artery in patients without and with intracranial aneurysms

The diameters of the A2 segment of the anterior cerebral artery in patients without and with intracranial aneurysms

The preparation and evaluation of thrombus model used for acute ischemic stroke

Objective To prepare a new thrombus model by fluid model method , which is suitable for evaluation of mechanical thrombectomy devices for acute stroke.Methods The fluid model adopted the Chandler loop theory , while the static model adopted conventional method.Mechanical properties of thrombi prepared by fluid model and static model were measured by manual elongation test ( 15 samples in each group) and catheter injection test (15 samples in each group ).Histological structure was compared among the above thrombus models ( 5 samples in each group ) and specimens of five patients with stroke by hematoxylin-eosin staining method.Then, thrombi in fluid model were utilized to establish embolization of vessels in swine model ( two pigs ) for evaluation of radiopacity.Independent-Sample test was performed to compare the maximum tensile length of two methods , and Fisher′s exact test was used to compare the rate of thrombus fragmentation after catheter injection test.Results The maximum tensile length of two models were (4.28 ±0.23) and (3.16 ±0.13) cm, respectively, and the difference was statistically significant (t=16.38, P<0.01);After catheter injection, the fracture rates of thrombus were 13% (2/15) and 60%(9/15), which were also statistically significant (P<0.05).As to histological structure, thrombi prepared by fluid model showed mixed thrombus structure , which similar to thrombi of stroke patients , But thrombi prepared by static model were replete with erythrocytes under the microscope .A total of eight vessels ( lingual arteries and superficial cervical arteries ) in two swines were successfully occlusive ( TIMI 0 or 1 ) , and sufficient radiopacity of each injected thrombus was observed.Conclusions The thrombi prepared by fluid model not only have good mechanical stability and sufficient radiopacity , but their histological structure is similar to thromboemboli retrieved from cerebral arteries of patients with acute stroke. Key words: Stroke ; Thrombosis ; Models,animal ;

Cerebral microembolism in patients with segmental left ventricular wall motion abnormalities

Background and purposeThe significance of segmental heart wall motion abnormalities for stroke is unknown. The aims of the study included (1) comparison of the frequency and type of embolic signals in the middle cerebral artery in patients with segmental left ventricular wall hypokinesis due to coronary heart disease with and without stroke, and (2) determination of the relationship between inflammatory parameters, fibrinogen level, dyslipidemia and microembolic signals in the middle cerebral artery in patients with segmental heart hypokinesis. Material and methodsThe study included 68 patients with segmental heart hypokinesis (33 without stroke [group I] and 35 with stroke [group II]), as well as 37 healthy volunteers and a reference group of 30 patients. Echocardiography and carotid/transcranial Doppler with detection of microembolic signals were performed. Patients from group I and II had erythrocyte sedimentation rate, leucocyte count, triglycerides, total cholesterol, HDL, and LDL examined. ResultsEmbolic signals were detected in patients with segmental heart hypokinesis significantly more frequently than in the control and reference groups. The high number of embolic signals, signals of high intensity, hypokinesis of the distal part of the intraventricular septum, increased cholesterol levels, LDL and triglycerides were all found more frequently in patients from group II than in group I. Embolic signals were detected more frequently in patients with high fibrinogen levels and leukocytosis. ConclusionsEmbolic signals in the middle cerebral artery in patients with segmental left ventricular hypokinesis have to be considered as a risk factor of stroke. The following changes are observed in patients with cardiogenic stroke: hypokinetic intraventricular septum, high intensity embolic signals, increased serum fibrinogen levels and leucocyte count. It may indicate the importance of these factors in the aetiology of stroke.

Reduced Cerebrovascular Reactivity in Posterior Cerebral Arteries in Patients with Primary Open-Angle Glaucoma

To evaluate the hemodynamics and vasoreactivity in the posterior cerebral artery (PCA) in patients with primary open-angle glaucoma (POAG). Case-control study. Thirteen POAG patients (age range, 40-60 years) with marked visual field loss (mean deviation [MD], <-6 dB); a preserved, mostly normal, central visual field of at least 5°; and best-corrected visual acuity of at least 20/40 formed the study group. Exclusion criterion was presence or history of any systemic disorder including cardiovascular diseases. The control group consisted of 12 healthy subjects matched for age and sex with the study group. Applying transcranial Doppler sonography, we measured hemodynamic parameters in both PCAs at baseline, under monocular reversing checkerboard stimulation, and under hyperventilation. The eye with more marked visual field loss was selected in glaucoma patients, whereas in controls, the tested eye was chosen randomly. Ipsilateral and contralateral PCA were defined according to the tested eye. Peak systolic velocity (PSV), end-diastolic velocity, mean velocity (MV), MV change percentage (MV%), resistivity index (RI), pulsatility index (PI). At baseline, RI (0.55 ± 0.04 vs. 0.52 ± 0.03; P = 0.04) and PI (0.88 ± 0.11 vs. 0.80 ± 0.07; P = 0.04) in the ipsilateral PCA were significantly higher in glaucoma patients than in controls. During checkerboard stimulation, MV% in both PCAs were significantly smaller in the glaucoma group than in controls (19.7 ± 7.2% and 19.0 ± 8.3% vs. 30.7 ± 7.9% and 27.5±9.0%, respectively; P = 0.001 and 0.02, respectively). During hyperventilation, glaucoma patients showed significantly lower MV% in the contralateral PCA than control subjects (-39.8 ± 9.6% versus -47.4 ± 7.0%; P = 0.03). Perimetric pattern standard deviation (PSD) in the tested eye was correlated significantly with RI and PI of the ipsilateral PCA during checkerboard stimulation (P = 0.003, r = -0.76; and P = 0.002, r = -0.76). The MV% of contralateral PCA was correlated inversely with PSD in the fellow eye (P = 0.02, r = -0.64). The difference in MV% between both PCAs was correlated positively with the difference in MD between 2 eyes (P = 0.003, r = 0.75). Under hyperventilation, PSV in the contralateral PCA was correlated negatively with the PSD in the fellow eye (P = 0.03, r = -0.60). Vascular insufficiency in the PCAs may be associated with POAG. Changes in the vasoreactivity of PCAs to central visual stimulation may precede marked central visual field loss.

Doppler Ultrasound Velocimetry of Middle Cerebral Arteries of Patients With Sickle Cell Disease At Aminu Kano Teaching Hospital: A Preliminary Report

Transcranial Doppler ultrasound scan is a noninvasive method of evaluating the major intracranial vessels. It is becoming an important screening tool for predicting high-risk sickle cell patients for developing cerebrovascular disease. This study evaluates the patients' characteristics, common indications, and findings on Doppler ultrasound of the middle cerebral arteries of sickle cell patients performed at Aminu Kano Teaching Hospital, Kano, Nigeria.This is a preliminary report of an ongoing review of the transcranial Doppler scans done at Aminu Kano Teaching Hospital. The records of all patients, the indications for Doppler examination, and major findings on the middle cerebral arteries were documented.There are 60 patients, consisting of 22 males and 38 females. Their ages ranged from 1.0 to 41.0 years, with mean of 11.58 ± 7.30 years. About a third of the patients were asymptomatic (38.3%). Those with headache constituted 20.0%, whereas those with past cerebral syndrome constituted 8.3%. Other indications include stroke (11.67%) and transient ischemic attack (3.3%).The mean peak systolic velocity of the middle cerebral artery measured 204.8 cm/s (±80 cm/s) and 208.8 (±79 cm/s) on the respective right and left side. This right-to-left difference was statistically significant (P = 0.046). Symptomatic and female patients showed higher mean peak systolic velocity values when compared with males, although the difference was not statistically significant.

Search for varicella zoster virus and herpes simplex virus-1 in normal human cerebral arteries

Virological confirmation of varicella zoster virus (VZV) vasculopathy is provided by presence of virus in the cerebral arteries, frequently associated with inflammation. Yet, cerebral arteries from normal subjects have never been studied for VZV DNA or antigen. We analyzed 63 human cerebral arteries from 45 subjects for VZV DNA and antigen, control herpes simplex virus (HSV)-1 DNA and antigen, and leukocyte-specific CD45 antigen. No cerebral arteries contained VZV or HSV-1 DNA or antigen; eight arteries from seven subjects contained leukocytes expressing CD45. Thus, the presence of VZV antigen in cerebral arteries of patients with stroke is likely to be clinically significant.

Doppler Ultrasound Velocimetry of Middle Cerebral Arteries of Patients With Sickle Cell Disease at Aminu Kano Teaching Hospital

Transcranial Doppler ultrasound scan is a noninvasive method of evaluating the major intracranial vessels. It is becoming an important screening tool for predicting high-risk sickle cell patients for developing cerebrovascular disease. This study evaluates the patients' characteristics, common indications, and findings on Doppler ultrasound of the middle cerebral arteries of sickle cell patients performed at Aminu Kano Teaching Hospital, Kano, Nigeria.This is a preliminary report of an ongoing review of the transcranial Doppler scans done at Aminu Kano Teaching Hospital. The records of all patients, the indications for Doppler examination, and major findings on the middle cerebral arteries were documented.There are 60 patients, consisting of 22 males and 38 females. Their ages ranged from 1.0 to 41.0 years, with mean of 11.58 ± 7.30 years. About a third of the patients were asymptomatic (38.3%). Those with headache constituted 20.0%, whereas those with past cerebral syndrome constituted 8.3%. Other indications include stroke (11.67%) and transient ischemic attack (3.3%).The mean peak systolic velocity of the middle cerebral artery measured 204.8 cm/s (±80 cm/s) and 208.8 (±79 cm/s) on the respective right and left side. This right-to-left difference was statistically significant (P = 0.046). Symptomatic and female patients showed higher mean peak systolic velocity values when compared with males, although the difference was not statistically significant.

Segmental left ventricular hypokinesis is associated with embolic signals in transcranial Doppler

Global left ventricular (LV) hypokinesis is considered to be the cause of stroke, while the significance of segmental wall motion abnormalities is still unknown. The aim of the study was to determine the frequency of embolic signals in the middle cerebral artery in patients with segmental LV wall hypokinesis in the course of coronary artery disease (CAD) with and without stroke. The study included 68 patients (aged 21-87 years) with segmental LV wall hypokinesis (33 patients without and 35 with stroke). The reference group comprised 30 patients (aged 43-76 years) with atherosclerotic risk factors; the control group comprised 37 healthy volunteers (aged 41-71 years). All subjects underwent echocardiography and carotid and transcranial Doppler ultrasound with the detection of microembolic signals. Embolic signals were observed significantly more often in patients with segmental LV wall hypokinesis than in the control and reference groups. In patients with CAD and stroke, an increased number of embolic signals (≥3) was observed significantly more often compared with patients without stroke. Compared with other locations, interventricular septum and apex hypokinesis was associated with a higher frequency of embolic signals in the middle cerebral arteries. Segmental LV motion abnormalities in the form of hypokinesis in patients with CAD are associated with the presence of embolic signals in the middle cerebral arteries, which may have clinical significance as a risk factor for stroke.