Comprehensive Ultrasound Assessment of the Craniocervical Circulation in Transient Global Amnesia.

OBJECTIVES: Structural changes and metabolic stress have been reported on diffusion-weighted magnetic resonance imaging in the cornu ammonis 1 area of the hippocampus in patients with transient global amnesia (TGA), but a consensus on pathogenesis is still lacking. The aim of our study was to perform a comprehensive ultrasound analysis of the cerebrovascular circulation in our population of patients with TGA. METHODS: One hundred patients with TGA and 50 age- and sex-matched control participants underwent ultrasound examinations of the cervicocranial circulation. RESULTS: The most significant risk factor for TGA was arterial hypertension (P < .01). There were no significant atherosclerotic lesions on the large arteries of the neck (mean internal carotid artery stenosis ± SD, 28.7% ± 11.7%) or on the large intracerebral arteries (good structural and hemodynamic status; P > .05). Rarely detected microembolic signals or a right-left cardiopulmonary shunt excluded an emboligenic mechanism of TGA (P > .05). The internal jugular vein valves were incompetent in 54% of patients with TGA, and this condition was associated with an increased risk of TGA (odds ratio, 4.16; 95% confidence interval, 1.91-9.04). The mean values of the breath holding index and pulsatility index, as parameters of small-vessel function, were within normal ranges and without differences between the TGA and control groups (P > .05). CONCLUSIONS: Our ultrasound examination did not detect significant structural atherosclerotic changes of cervicocranial arteries, and an emboligenic mechanism was excluded. Only a significant rise of blood pressure in TGA and significant valvular insufficiency of the internal jugular vein were established. New research should clarify whether these simultaneous functional circulatory changes have relevance for metabolic stress in the cornu ammonis of the hippocampus.

Migraine with aura and TCD bubble-test: The significance of positive result.

BACKGROUND/AIM: The association between the right-to-left shunt (RLS) and migraine with aura (MA) has been proven so far. The aim of this study was to determine if the presence of RLS detected as a result of transcranial doppler (TCD) bubble-test, makes any difference in clinical presentation, aura and headache in patients with MA. METHODS: A single-group descriptive study was conducted on 153 patients diagnosed with MA. TCD bubble-test was performed on 135 of them. The recorded demographic and clinical features of patients were analyzed and compared with the results of the TCD bubble test. RESULTS: In the group of 135 patients, 88 (65.2%) had positive TCD bubble-test. The difference in the investigated clinical features of patients of the patients and aura between the patients with and without RLS, was not found. CONCLUSION: The results of our study confirm a high prevalence of right-to-left shunt in patients with MA, but the clinical relevance of this association was not shown.

Transcranial Doppler assessment of cerebral vasomotor reactivity in evaluating the effects of vinpocetine in cerebral small vessel disease: a pilot study.

BACKGROUND: There are still dilemmas about the vasodilating effect of vinpocetine, a synthetic ethyl alkaloid vincamine. The method of measuring cerebral vasomotor reactivity (VMR) by transcranial Doppler (TCD) technique before and after administration of the medication was used to estimate the degree of arterioles vasodilatation. The aim of this study was to test of the vasodilating effect of vinpocetine in patients with cerebral small vessel disease (SVD) by measuring cerebral VMR. MATERIAL AND METHODS: Thirty patients with SVD were on 3-month-long oral treatment with 15 mg vinpocetine daily. Cerebral VMR was determined by breath holding test. The breath holding index (BHI) was calculated in standard manner and values > 0.69 were considered normal. At the baseline, before treatment (I), BHI, modified Rankin scale (mRS) score, Mini Mental State Examination (MMSE) score were determined. One month later (II) BHI was assessed again, while after 3 months of treatment (III) we analyzed BHI, mRS score and MMSE score. RESULTS: The average age of patients was 61.4 +/- 11.5 years (range 40 to 77 years), 18 (60%) female and 12 (40%) males. Values of BHIs were increased during treatment at the right MCA (I) 1.18 +/- 0.53, (II) 1.26 +/- 0.54, (III) 1.37 +/- 0.41, with statistical significance between I and III measurement (p < 0.05). An increase was noted on the left MCA (I) 1.25 +/- 0.53, (II) 1.31 +/- 0.55 and (III) 1.32 +/- 0.42, but it did not reach statistical significance (p > 0.05). Mean MMSE score significantly increased from baseline 27.4 +/- 2.3 to 28.5 +/- 2.0 after three months of treatment (p < 0.001). Functional status showed a statistically significant improvement with mRS score increasing from 2.1 +/- 1.0 to 1.1 +/- 0.6 (p < 0.001). CONCLUSION: This pilot study showed that 3-month-long oral treatment with vinpocetine 15 mg daily had tendency to increase BHI, indicating improvement of cerebral VMR. It is possible that higher doses of vinpocetine are needed to achieve substantial increase of VMR.

[Incompetence of internal jugular vein valve in patients with transient global amnesia].

BACKGROUND/AIM: Transient global amnesia (TGA) could be related to acute ischemic disturbances in mesial parts of temporal lobes, which are important for memory. Incompetence of internal jugular vein (IJV) valve with venous congestion causes venous microthrombosis of hippocampus. The aim of this study was to investigate the frequency of IJV valve incompetence, as well as other hemodynamic and structural properties of cerebral circulation in TGA patients. METHODS: IJV valve competence was investigated in 40 TGA patients and 30 persons of the control group (matched by age and sex), as well as detection of microembolic signals and detection of right to left cardiopulmonal shunt, cerebral vasomotor reactivity and echocardiography by color triplex ultrasonography and transcranial doppler. RESULTS: A significant difference in frequency of IJV valve incompetence was found between the TGA patients and the control persons (55% TGA vs. 30% controls; p < 0.001). We did not find a significant structural (plaques frequency) or hemodynamic (flow velocity, pulsatility index) differences on arteries of the neck and cerebral arteries between the TGA patients and the controls, except for the increased pulsatility index on the basilar artery (40% TGA vs. 16.6% controls; p < 0.01) and decreased vasomotor reactivity in TGA patients (50% TGA vs 26.6% controls;p < 0.001). Microembolic signals were detected very rarely (17.5% TGA patients vs. 13.3% controls; p > 0.05), as well as right to left cardiopulmonal shunt (15% TGA vs. 16.6% controls; p > 0.05), indicating that embolism was not important for pathogenesis of TGA. Transesophageal echocardiography confirmed it, because only one TGA patient had a potent foramen ovale. CONCLUSION: We found a significantly increased frequency of IJV incompetence in the TGA patients, which confirmed the role of vein drainage disturbances in pathogenesis of TGA.

[Transcranial Doppler test for evaluation of cerebral artery embolism--microemboli detection].

About one third of ischaemic cerebrovascular diseases have embolic properties. Because of that, transcranial Doppler (TCD) test for detection of microembolic signals (MES), as the only one method for detection of microemboli, is a very important test for the evaluation of cerebral artery embolism. Cerebral emboli are particles of thrombus or atheromatous plaque, platelet aggregates, lipid or air particles in cerebral circulation, which can occlude arterioles and cause ischaemic transient attack (TIA) or stroke. Most frequently, they derive from exulcerated plaques of the carotid bifurcation or the aortic arch, from the atrial thrombus, prosthetic heart valves, as well as during carotid endarterectomy, arterial stent, aortocoronary by-pass. For MES detection, bilateral monitoring of a. cerebri mediae (ACM) is performed with each probe held in place over a temporal bone. MES are represented as brightly coloured embolic tracks as they pass through the insonated arteries. A computer hard disk provides continuous recording that is replayed for counting embolic signals. Colour intensity or acoustic range indicate the size and structure of MES. MES in the range of one ACM indicate the source of embolism on the ipsilateral carotid artery, while the bilateral detection of MES suggests a cardiogenic source. Indications for TCD detection of MES are the evaluation of pathogenesis and risk for embolic stroke or TIA and assessing the source of embolism. We started applying this method at the Institute of Neurology in Belgrade 2 years ago. We have investigated 78 patients till today and detected MES in 23 patients (28.7%). The Report of the Therapeutics and Technology Assessment Subcommittee of the American Academy of Neurology, 2004, considers that TCD is probably useful for detection of cerebral MES in various cardiovascular and cerebrovascular disorders and procedures.

[Plasminogen activator inhibitor-1 in the evolution of stroke]. / Inhibitor 1 aktivatora plazminogena u evoluciji mozdanog udara.

Fibrinolytic activity in the acute stroke was examined by monitoring the level of plasminogen activator inhibitor-1 (PAI-1), as one of the indicators of fibrinolytic activity. Given the role of PAI-1 in the processes of atherogenesis and thrombogenesis, plasma PAI-1 level was measured in 59 patients (up to 50 years of age) with atherothrombotic stroke (verified by computed tomography scanning or magnetic resonance imaging of brain) in the period from 12 to 24 hours (I analysis) and 30 days after the onset of stroke (II analysis); then, it was correlated with plasma PAI-1 level in the control group (57 healthy subjects), which was 2.86 +/- 0.70 U/ml. It was found that PAI-1 level was significantly higher in the acute stroke (I analysis: PAI-1 = 4.10 +/- 1.40 U/ml, p < 0.001; II analysis: PAI-1 = 3.64 +/- 0.90 U/ml, p < 0.001), while fibrinolytic activity was lower, especially on the first day from the stroke that was not completely increased even after 30 days. There was no difference in PAI-1 levels between the subgroups of patients with infarction and lacunar cerebral ischemia (p > 0.05), as well as between females and males (p > 0.05). Along with significantly increased fibrinogen level (4.65 +/- 1 g/l, in the controls--2.83 +/- 0.64 g/l, p < 0.001), significantly higher triglycerides (2.04 +/- 0.76 mmol/l, in the controls--1.38 +/- 0.54 mmol/l, p < 0.001) and lipoproteins(a) (0.405 +/- 0.29 g/l, in the controls--0.172 +/- 0.14 g/l, p < 0.001) were found, correlating with higher plasma PAI-1 level in these patients. The increased plasma level of PAI-1 pointed to possibility of decreased fibrinolytic activity in pathogenesis of ischemic stroke, as well as, risk of reinsult, which had been the greatest after the onset of stroke and declined gradually within several weeks.