Transcranial Doppler in brain death confirmation in clinical practice.

PURPOSE: Transcranial Doppler (TCD) can be used as a confirmatory test in brain death. The aim was to present the usefulness of TCD in brain death confirmation. MATERIALS AND METHODS: Forty-four patients with severe brain lesions leading to brain death were treated over a 4-year period. After the clinical diagnosis of brain death was made, the appropriate confirmatory test was chosen according to patient condition, taking into consideration the restrictions of the test protocol. Due to the inconclusive test results, some patients underwent repeat testing. RESULTS: Among 44 patients, 19 had neurotrauma, 11 massive aneurysmal subarachnoidal hemorrhages, 1 arteriovenous subarachnoidal and parenchymal hemorrhage, 12 hypertensive parenchymal hemorrhages, and 1 ischemic stroke. As a primary test, TCD was used in 30, brain scintigraphy in 2, multislice CT angiography (CTA) in 10, and cerebral angiography in 2 patients, and the diagnosis was confirmed in 26, 3, 9 and 2 patients, respectively. Due to inconclusive results CTA was repeated in five patients. In patients in whom TCD was applied, the time to confirm the diagnosis was the shortest, and in most (61 %) cerebral circulatory arrest was confirmed within 2 hours of clinical diagnosis. CONCLUSION: TCD is a favorable confirmatory test for cerebral circulatory arrest in brain death diagnosis.

Perception of stroke in Croatia--knowledge of stroke signs and risk factors amongst neurological outpatients.

BACKGROUND AND PURPOSE: The aim of this hospital-based survey was to determine baseline stroke knowledge in Croatian population attending the outpatient services at the Department of Neurology. METHODS: A multiple choice questionnaire was designed, divided into three sections: (i) demographic data, (ii) knowledge of stroke risk factors and stroke signs and (iii) actions the patients would undertake if confronted with risk of stroke and information resources regarding health. RESULTS: The analysis included 720 respondents (54.9% women). The respondents most frequently indicated stroke symptoms as following: speech disorder 82%, paresthesiae on one side of the body 71%, weakness of arm or leg 55%, unsteady gait 55%, malaise 53%, monocular loss of vision 44%. The risk factors most frequently identified were hypertension 64%, stress 61%, smoking 59%, elevated lipids 53%, obesity 52%, coagulation disorder 47%, alcoholism 45%, low-physical activity 42%, elderly age 39%, cardiac diseases 38%, weather changes 34%, drugs 33% and diabetes 32%. If confronted with stroke signs 37% of respondents would consult the general practitioner and 31% would call 911 or go to a neurologist. Amongst patients with a risk factor, only diabetics were aware that their risk factor might cause stroke (P < 0.001). Respondents with lowest education had the least knowledge regarding stroke signs (P < 0.01). DISCUSSION: The results of this study indicate that respondents showed a fair knowledge about stroke signs and risk factors for stroke. The results of our study will help to create and plan programmes for improvement of public health in Croatia.

Distinguishing Parkinson's disease and essential tremor with transcranial sonography.

OBJECTIVES: Until today there is no reliable test that can clearly distinguish Parkinson's disease (PD) from the essential tremor (ET). Our aim was to determine the usefulness of the transcranial sonography (TCS) in the differential diagnosis of the PD and ET as well as the interobserver reliability for this method. METHODS: Transcranial sonography of substantia nigra and clinical examination were performed on 80 PD patients, 30 ET patients, and 80 matched controls by two independent physicians. RESULTS: Bilateral SN hyperechogenicity over the margin of 0.20 cm(2) was found in 91% of PD patients, 10% of healthy subjects, and in 13% patients with ET. Interobserver agreement for this method was significant (Student's t-test, P = 1.000). CONCLUSIONS: Substantia nigra hyperechogenicity on TCS is a highly specific finding of PD, where in healthy individuals or in ET patients, it might correspond to an increased risk of developing PD later in life or might also be because of the impairment of nearby area of nucleus ruber in ET patients, as suggested by positron emission tomography studies. TCS may serve as a practical and sufficiently sensitive neuroimaging tool in PD diagnoses and in distinguishing it from ET; its repeatability and accuracy might add to its practical value.

Pineal gland cyst evaluated by transcranial sonography.

Transcranial sonography (TCS) has never been used in the evaluation of morphology of pineal gland. The aim of the study was to assess the possibility of TCS to distinguish normal from cystic pineal gland and to correlate its size with magnetic resonance imaging (MRI) at the first examination and during follow-up. Sixty patients with previously made MRI of the brain were evaluated by two independent observers using TCS, blinded to the results of the MRI. Inappropriate bone window limited TCS examination in seven patients. All 14 pineal gland cysts (PGC) seen on MRI were detected by both observers using TCS. Control group consisted of 39 healthy examinees. No statistically significant difference has been found between: PGC size measured by first and second observer by TCS (P = 0.425), PGC size measured by TCS and MRI (first observer, P = 0.353; second observer, P = 0.425), size of the pineal gland measured by TCS and MRI in control group (first observer, P = 0.497; second observer, P = 0.370) or interobserver variability in control group (P = 0.373). The MRI and TCS follow-up of ten patients after six months did not show any difference in size of PGC. TCS can be used as a method in detection, measurement and follow-up of PGC.

Aortic arch dissection presenting with hemodynamic spectrum of aortic regurgitation on transcranial Doppler.

The diagnosis of aortic dissection is frequently missed at the time of hospital admittance. Neurological presentations are rare, and neuro-sonography is rarely used. We describe a patient with atypical clinical presentation of aortic arch dissection in whom neuro-sonological investigations showed a "cathedral like" haemodynamic spectrum of aortic regurgitation, directing the investigation towards the diagnosis.

Polymorphism of apoprotein E (APOE), methylenetetrahydrofolate reductase (MTHFR) and paraoxonase (PON1) genes in patients with cerebrovascular disease.

Although controversial, data on the genetic polymorphism of apoprotein E (APOE), methylenetetrahydrofolate (MTHFR) and paraoxonase (PON1) genes implicate their role in the development of cerebrovascular disease. The aim of this study was to assess the association of polymorphism of APOE, MTHFR and PON1 genes in 56 stroke and 36 carotid stenosis patients, and in 124 control subjects by PCR-restriction fragment length polymorphism analysis. In the stroke group a significantly different MTHFR genotype distribution (p=0.004, odds ratio for T/T of 17.571), but no significant difference in APOE and PON1 allele and genotype distribution compared to the control was found. The carotid stenosis group exhibited a significantly different APOE allele and genotype distribution (p=0.023, odds ratio APOEepsilon3epsilon4 of 4.24), but no significant difference in the MTHFR and PON1 allele and genotype distribution from the control group. The preliminary results obtained in this study revealed an association of the MTHFR and APOE gene polymorphism with cerebrovascular disease, suggesting a significant risk for stroke in subjects who are homozygous for the T allele and for carotid stenosis in subjects having APOEepsilon3epsilon4 genotype. Additional studies in larger patient groups are needed to confirm these observations.

Vertebral artery hypoplasia--sex-specific frequencies in 36 parent-offspring pairs.

The major interest in vertebral artery (VA) hypoplasia comes from its possible connection to migraines with aura as well as from the fact that it is one of the risk factors for a stroke. Therefore, the aim of this preliminary study was to investigate the mode of inheritance of VA hypoplasia. Initially, color Doppler of VA was performed in 64 first- and second-degree relatives of 33 probands, and the presence of VA hypoplasia was confirmed according to the already established criteria. Since a higher prevalence of VA hypoplasia (15.6%) in probands'relatives in comparison with 2.34% in the general population of Croatia was indicative of a strong familial predisposition for this condition, an analysis of family data by means of Pearson's chi-square statistics has been performed. In this analysis, the observed sex-specific frequencies of 36 parent-offspring pairs composed only of affected parent and his/her (affected or non-affected) offspring are compared to the frequencies as expected under eight proposed models. For both--autosomal and X-linked monogenetic inheritance--four hypotheses have been chosen, assuming that the individuals having the affected allele (in combination with a healthy one) have 100%, 50%, 40% and 0% chances of developing VA hypoplasia. Out of eight tested models only two--completely dominant and completely recessive X-linked models--were rejected. But, from the six non-rejected models, goodness-of-fit statistics showed that the hypothesis of X-linked inheritance of VA hypoplasia with the "healthy" allele being stronger (60% effect on phenotype)--almost perfectly fit the data (chi2 = 2.0023; df = 7; p = 0.9597). Further research encompassing a more enlarged family sample is needed to confirm the present findings.

Value of color-Doppler imaging in diagnosis of intrabulbar and intraorbital tumors.

Patients with intrabulbar and intraorbital tumours have been investigated by colour Doppler imaging. In the first group there were 20 patients with malignant melanoma of the uvea and in the second group there were 19 patients with cavernous hemangioma. The third group was a control group represented by 20 healthy individuals. In the group of patients with uveal melanoma it has been established that every patient, except one, has a blood flow inside of tumour tissue. Internal blood flow of intraorbital hemangioma was slower than inside the melanoma and the resistance index was lower. Comparison of blood flow in all patients has shown that there is no statistically significant difference between ophthalmic artery, central retinal artery and posterior ciliary arteries except in maximal blood flow in central retinal artery and posterior ciliary arteries.

Color Doppler flow imaging of ocular tumors.

AIM: To analyze the usefulness of color Doppler flow imaging in the differentiation of benign and malign ocular tumors. METHODS: Blood flow in tumor and ocular blood vessels was assessed by color Doppler flow imaging in 20 patients with malignant melanoma of the uvea and 19 patients with cavernous hemangioma. Blood velocity measurements in orbital vessels in these patients were compared with the same measurements in 20 healthy individuals. RESULTS: Blood flow inside the tumor tissue was observed in all patients, except in a single case of uveal melanoma. Internal blood flow of intraorbital hemangiomas was slower and their resistance index lower than that of melanomas. Patients with a tumor did not differ from the controls in blood flow velocities in the ophthalmic artery, central retinal artery, and posterior ciliary arteries. Only the patients with uveal melanoma had higher maximal blood flow in central retinal artery and posterior ciliary arteries compared to other patients. CONCLUSION: Color Doppler flow imaging of blood flow can be a useful method to assess the vascularization of ophthalmological tumors, and to differentiate uveal melanoma from orbital hemangioma.

Color Doppler flow imaging (CDFI) of the vertebral arteries--the normal appearance, normal values and the proposal for the standards.

In order to assess mean diameters and blood flow velocities (BFV), Color Doppler Flow Imaging (CDFI) of vertebral arteries (VA) was performed. Five hundred and ninety six persons without carotid disease or symptoms related to vertebrobasilar system were analyzed by CDFI of VA. Mean right VA diameter was 3.37 +/- 0.6 mm and left 3.55 +/- 0.61 mm. Women had thinner VA (p < 0.05). Left VA was wider (p < 0.05). Mean right BFV was 48.31 +/- 14.09 cm/s and left 48.93 +/- 13.94 cm/s. Females had higher BFV (p < 0.05). BFV didn't very with age (p > 0.05). The VA hypoplasia was present in 2.34%, asymmetry in 15% (left VA dominant in 64%). Visualisation of V1 and V2 segment was possible in 100% and of the origin in 81.7% on the right, and 80.7% on the left side. CDFI is a reliable method for evaluation of VA. Left VA was wider. Women had thinner VA. Hypoplasia was present in 2.34% and asymmetry in 15%.

Role of vertebral artery hypoplasia in migraine.

The role of cerebral hypoperfusion in the posterior circulation has not been clearly established in migraine. The purpose of this study was to determine the role of vertebral artery (VA) hypoplasia in the pathogenesis of migraine. We studied the extracranial part of VA in 59 migraine patients (17 with and 42 without aura) using color Doppler. In migraine with aura, 29% of patients had hypoplastic VA, and in migraine without aura 7%. In migraine with aura, mean diameter of the right VA was 2.7+/-0.7 mm, and of the left 3.3+/-0.7 mm; in migraine without aura mean diameter was 3.1+/-0.5 mm on the right, and 3.3+/-0.6 on the left. In migraine with aura, mean systolic blood flow velocity was 55+/-16 cm/s on the right, 60+/-17 cm/s on the left, in migraine without aura 57+/-18 cm/s on the right, 57+/-18 cm/s on the left. We observed higher frequency of hypoplastic VA in migraine with aura, suggesting that hypoplasia of VA may be an additional factor which can lead to hypoperfusion in the posterior circulation during the aura phase.

A correlation of 5-hydroxytriptamine and cerebral vasoreactivity in patients with migraine.

Cerebral haemodynamics and the level of serum 5-hydroxytriptamine (5-HT) were analysed in 21 migraine patients (8 with and 13 without aura) during the headache-free period as well as the attack. Cerebral vasoreactivity was evaluated by acetazolamide test and Transcranial Doppler ultrasonography (TCD). TCD findings were within normal ranges in the majority of migraine patients. Patients with migraine without aura had higher blood flow velocities (BFV) than patients with aura. Comparison of BVF and pulsatility index (PI) data patterns in migraine with and in migraine without aura during the attack revealed differences indicating cerebral hypoperfusion. It was noticed that systolic BFV decreased in migraine with aura on the headache side while PI increased. In migraine without aura, both systolic BFV and PI increased. 5-HT findings were heterogeneous. Reduction of cerebral vasoreactivity was observed especially in migraine with aura. Our results suggest different pathogenic mechanisms between migraine with and without aura, supporting the neurogenic inflammation theory.