Assessment of the clinical utility of transcranial doppler in acute stroke patients

The aim of this work is to correlate clinical features of stroke progression with transcranial Doppler findings of arterial reperfusion, and to define the prevalence and time course of Doppler emboli signals after acute stroke Transcranial Doppler [TCD] as a non-invasive, simple, cheap, and repeatable gives on-line information about recanalisation of obstructed vessels. An increase in TCD velocity can be due to stenosis, vasospasm, or hyperemia. The microemboli signals are transient, unidirectional, 3 to 60 decibels in amplitude, and have a clicking sound. Their duration is inversely proportional to their velocity. They are randomly distributed within the cardiac cycle. The overall prevalence of microemboli in acute stroke patients depends on patient population, treatment regimens, study protocols, and prior stroke or TIA. One hundred and fifteen stroke patients [61 females and 54 males], with mean age 66.7+1-15.4, were valuated clinically on admission using National Institute of Health Stroke Scale [NIHSS], TCD study was done on admission and repeated for patients who stayed more than one day in the hospital. Patients were classified according to the perfusion patterns, CT appearance and risk factors of stroke. Eighty-eight patients [49 men and 39 women] with mean age 67.2 +/- 13.9 years were successfully monitored for microemboli signals [MES]. Clinically, 18[20%] patients were diagnosed as TIA and 70[80%] as complete stroke. There were 11 with atrial fibrillation [AF], 17 with myocardial infraction [MI] 14 with internal carotid artery stenosis [CS], and 46 patients with other risk factors such as hypertension, diabetes, cigarette smoking and alcohol consumption. The overall prevalence MES was 10.2% [12% in MI patients, 0% in AF patients, and 50% in CS patients]. Carotid stenosis patients had significantly [p=0.04] higher prevalence of embolic signals than the other groups. There was a significant difference [p=0.001] in the mean velocities [MV] between the four groups in the healthy hemisphere, but not in the diseased one. There was a significant difference [p=0.05] in healthy sides between AF and other risk factors group. Also there was a significant difference [p=0.01] in both healthy and diseased sides between CS and AF patients. There was a significant difference [p=0.01] between four groups in the pulsatility indices [P1] in the diseased sides but not in the healthy sides. Also positive correlation was obtained between perfusion pattern and NIHSS in each group of stroke subtype. It was higher in both lacuner infarcts and normal CT groups and lower in territorial group. The perfusion patterns evolved from hypoperfusion, normal perfusion, and then hypoperfusion side with time. A negative correlation was established between the time and asymmetry indices [Al], more significant [p=0.02] in hypoperfusion group. Conclusions: In conclusions TCD is a helpful method for studying the pathophysiological mechanisms in stroke. IT is recommended to early, prolonged monitoring, and strict setting of TCD machine. Cerebral embolism is the likely mechanism of stroke in MI patients, while haemodynamic insufficiency may be cerebral haemodynamic state. Perfusion patterns in the acute stage are indicators for the clinical condition and should be combined with CT results and clinical scoring

Brain mapping in comparison to EEG and CT in transient ischemic attacks

This study was carried out on 68 patients suffering from TIA either of carotid or vertebro basilar origin with the aim of investigating the role of brain mapping in diagnosis of TIAs. In addition to the clinical assessment, brain mapping was carried out simultaneously with a 16 channel EEG recording, being done within 12 hours from the disappearance of symptoms, or sometimes could be done during the attack. Also, CT was done 48 to 72 hours following the attack. The patients were 47 males and 21 females with age ranged between 42 - 82 years. According to clinical presentation and results of neuro examination, patients could be classified into 2 main groups: Patients with TIA of carotid origin [44] and those of TIA affecting VB system [24]. The clinical presentation within each group was rather variable with most of the patients showing combinations of relevant neuro symptoms and signs. CT showed relevant infarctions [mostly lacunar] in 20% of patients, EEG was positive in 57%, while brain mapping gave positive figures in about 85% of patients. The most commonly encountered map findings were decrease in alpha power and increase in the power of delta and theta bands. Also, it could differentiate well between TIAs of carotid origin [main abnormality is asymmetry] and those of VB origin [main abnormality is the increase of power of slow bands posteriorly]. Both EEG and mapping gave higher positive figure with increased duration of the attack

CT versus MR in epilepsy

One hundred twenty seizure patients with positive EEG were studied using CT and MR to determine the efficacy of each in detection of epileptic focus. MR was considered to be the imaging procedure of choice for detection of an epileptogenic focus in seizure patients. When indicated, CT may be done as a second procedure to distinguish neoplasms from thrombosed vascular malformations, or to detect small foci of calcification and other lesions

Clobazam as adjunctive therapy in drug-resistant seizures: clinical, EEG and psychological study

The anticonvulsant effect of clobazam in refractory epileptics of all types in different age groups was studied. Subjects were kept on their basic monotherapy antiepileptic regimens with phenytoin, valproic acid or carbamazepine [to which the response was unsatisfactory], in addition to 0.5-1 mg clobazam/kg/day for 6 months. Clinical, EGG and psychological assessments were carried out at the start, 3 months and at the end of the study. An improvement [50% reduction of seizure frequency or more] was noticed in 24 patients, but with no statistical significance. None of the subjects in this study developed tolerance. There was no correlation between the degree of the effect and serum levels of phenytoin and carbamazepine; while valproic acid was positively correlated, but without statistical significance. Normal EEG patterns were obtained in two patients. Although the present study was populated by negative sample of problem patients, the results were encouraging to recommend inclusion of clobazam in unproblematic cases with expected greater success rates than have been observed so far