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Yair Lampl

Publications and source records attributed to Yair Lampl.

At least 19 recordsLinked to original sources
PubMed2006

Low-level laser therapy applied transcranially to rats after induction of stroke significantly reduces long-term neurological deficits.

BACKGROUND AND PURPOSE: Low-level laser therapy (LLLT) modulates various biological processes. In the present study, we assessed the hypothesis that LLLT after induction of stroke may have a beneficial effect on ischemic brain tissue. METHODS: Two sets of experiments were performed. Stroke was induced in rats by (1) permanent occlusion of the middle cerebral artery through a craniotomy or (2) insertion of a filament. After induction of stroke, a battery of neurological and functional tests (neurological score, adhesive removal) was performed. Four and 24 hours poststroke, a Ga-As diode laser was used transcranially to illuminate the hemisphere contralateral to the stroke at a power density of 7.5 mW/cm2. RESULTS: In both models of stroke, LLLT significantly reduced neurological deficits when applied 24 hours poststroke. Application of the laser at 4 hours poststroke did not affect the neurological outcome of the stroke-induced rats as compared with controls. There was no statistically significant difference in the stroke lesion area between control and laser-irradiated rats. The number of newly formed neuronal cells, assessed by double immunoreactivity to bromodeoxyuridine and tubulin isotype III as well as migrating cells (doublecortin immunoactivity), was significantly elevated in the subventricular zone of the hemisphere ipsilateral to the induction of stroke when treated by LLLT. CONCLUSIONS: Our data suggest that a noninvasive intervention of LLLT issued 24 hours after acute stroke may provide a significant functional benefit with an underlying mechanism possibly being induction of neurogenesis.

Animals↗
PubMed2006

Prospective evaluation of malignant middle cerebral artery infarction with blood-brain barrier imaging using Tc-99m DTPA SPECT.

BACKGROUND: Malignant middle cerebral artery (MMCA) infarction is associated with severe brain edema which may lead to a rapid deterioration of consciousness, increase of intracranial pressure, brain midline shift and finally, herniation. We examined the correlation between the degree of the blood-brain barrier (BBB) permeability and MMCA. METHODS: Twenty-five consecutive patients (17 men and 8 women, mean age 62.1+/-10.1) were included in the study. Each patient had a daily clinical examination, and the neurological deficits were scored using NIHSS score. A CT without contrast material was performed in all patients. (99m)Tc-DTPA SPECT was performed at 36 h after the stroke. A quantitative index of BBB breakdown (disruption index) was calculated. RESULTS: The mean volume of stroke was 138+/-87 cm(3). The mean DTPA disruption index was 6.6+/-4.6 (range 1.0-21.0). The mean NIHSS score was 14+/-4 (p=0.2). Five of 25 patients had brain herniation as evidenced on brain CT. The volume of stroke was only marginally elevated in patients with herniation (p=0.062). All patients showed significant, inverse correlation between NIHSS score and DTPA uptake (r=-0.43, p=0.033). There was a significant correlation between the extent of DTPA distribution (more than one vascular territory) and the occurrence of herniation (p<0.001). CONCLUSIONS: DTPA-SPECT imaging is a reliable complementary predictive tool in patients with an MCA stroke. The specific pattern found on DTPA SPECT, compatible with diffuse BBB disruption, may be of value in predicting "malignant MCA."

Aged↗
PubMed2006

In vivo imaging of apoptosis in patients with acute stroke: correlation with blood-brain barrier permeability.

BACKGROUND: We wished to determine the ability of radiolabeled annexin V to concentrate at sites of ischemic injury in patients with acute cerebral stroke. Secondly, we sought to correlate annexin V imaging in these patients with the degree of blood-brain barrier (BBB) breakdown. METHODS: Twelve patients with acute stroke had a complete neurological examination, including the National Institutes of Health (NIH) stroke scale and the Glasgow Coma Score (GCS). A non-contrast CT scan was performed on all patients. A SPECT of the brain was obtained 2 h after injection of annexin V. The integrity of the BBB was evaluated in seven patients using Tc-99m-DTPA brain SPECT. RESULTS: All patients had an infarct in the MCA territory. Eight patients had abnormal increased annexin V activity, which was more common in patients with cortical strokes (P = 0.01). The concentration of annexin had no correlation to the volume of stroke, but it was significantly and inversely related to the GCS on admission (r = -0.7, P = 0.02). Foci of apoptosis were noted contralateral to the affected hemisphere as well. All seven patients who underwent DTPA SPECT showed breakdown of the BBB. DTPA uptake was significantly and positively associated with NIH score (r = 0.80, P = 0.01) and inversely associated with GCS (r = -0.89, P = -0.03). CONCLUSION: This study shows that it is possible to identify in vivo regions of ischemic neuronal injury using radiolabeled annexin V in patients with acute stroke. Annexin imaging can play a major role in the selection of therapy in the initial period following stroke in adults.

Acute Disease↗
PubMed2006

[123I]-FP/CIT SPECT imaging for distinguishing drug-induced parkinsonism from Parkinson's disease.

Parkinsonism in patients taking neuroleptic medications might be induced by dopamine receptor blockade alone or by dopamine blockade with nigrostriatal dysfunction. The differentiation between Parkinson's disease (PD) and drug-induced parkinsonism (DIP) is difficult to assess on clinical grounds alone. In this study, we have evaluated the clinical characteristics and striatal binding of (123)I-FP-CIT (N-omega-fluoropropyl-2beta-carboxymethoxy-3beta-{4-iodophenyl}tropane) in patients who developed DIP. A total of 20 patients (mean age, 62 +/- 13 years) who developed parkinsonism while on neuroleptic agents and 10 age-matched controls were enrolled. [123]-FP-CIT single-photon emission computed tomography (SPECT) was performed in all subjects. Neurological assessment was performed with the Motor part of the Unified Parkinson's Disease Rating Scale. [123]-FP-CIT binding of the entire striatum, caudate, and putamen was calculated. Patients were divided into two subgroups according to SPECT results for comparison of clinical characteristics. There were 9 patients who had normal scans and 11 who showed significantly diminished striatal binding, suggesting degeneration of the nigrostriatal system. Subanalyses of abnormal scans revealed significantly diminished binding in the caudate (P < 0.001 for right and left caudate) and putamen (P = 0.002 and P < 0.05 for right and left putamen, respectively). There were no differences in clinical features between patients with normal and abnormal scans. Symptoms included asymmetric tremor, bradykinesia, and rigidity in both groups. Freezing gait was present in two patients with normal scans. These results indicate that DIP is clinically indistinguishable from PD. Brain imaging with FP-CIT helps to determine whether DIP is entirely drug-induced or an exacerbation of subclinical PD.

Aged↗
PubMed2006

Visual spatial neglect in multiple sclerosis.

Neuropsychological dysfunction in multiple sclerosis (MS) patients is now a well-established clinical finding. We examined the entity of visual spatial neglect in demyelinating disease and its correlation to the functional and neuroradiological parameters. The phenomenon of visual spatial neglect was examined in 20 (5 male and 15 female) MS patients. Two different examination methods were used--the line bisection test and the random shape cancellation test. The results were compared with 20 aged matched control individuals. The correlation of the visual spatial neglects to neurological deficits and handicaps, using Kurtzke's Expanded Disability Status Scale (EDSS), as well as with the MRI's neuroradiological findings, was analyzed. A highly significant different result on the line bisection test for three various line lengths (p = .006, p < .0001, p < .001) with displacement towards the right side was found. In all the cancellation subtests, a significant difference in error rate was found in comparing patients to controls toward a higher one on the left side of the MS patients (p = .005, p < .002, p < .0001 and p = .02 in the left side subtest, and p = n.s. in the right side subtest). There was no significant correlation between the cancellation tests and bisection results and the EDSS scale data, as well as with the neuroradiological findings. The present results demonstrate the presence of visual spatial neglect among MS patients, even without the demonstration of a characteristic neuroanatomical lesion. The hypotheses for this finding are discussed with a stress on the possibility of disruption of multiple intrahemispheric connections, especially under the condition of asymmetry of dominance regarding spatial attention.

Adult↗
PubMed2006

Acute steroid responsive small-fiber sensory neuropathy: a new entity?

Small-fiber neuropathy is often idiopathic and commonly follows a chronic course. Treatment is often effective in treating the core symptom of pain, but it has no effect on the pathologic process. We describe four patients with acute small-fiber neuropathy who responded dramatically to steroid therapy. All patients had acute onset neuropathic pain, normal nerve conduction studies, and evidence of small-fiber dysfunction in quantitative sensory testing and skin biopsy. Symptoms were distal and symmetrical in three patients and generalized in one patient. In two cases, the neuropathy presented as an erythromelalgia-like syndrome. Marked clinical improvement occurred 1-2 weeks after oral prednisone therapy was initiated. Three patients remained symptom free, and one patient experienced recurrence of neuropathy after prednisone was tapered.

Adolescent↗
PubMed2006

[Guidelines for the management of acute stroke--2005].

Stroke is a major cause for morbidity and mortality in Israel, the third most common cause of death and the main cause for neurological disability among adults. Several significant breakthroughs occurred over recent years in the management of stroke, and acute stroke has increasingly been recognized as a medical emergency--a "brain attack" comparable to a "heart attack". Several new scientific publications, guidelines and consensus statements from Europe and North America necessitate a paradigm shift in the management of acute stroke. The guidelines focus on a number of issues: acute stroke as a medical emergency, dedicated stroke units, early reperfusion therapy for acute ischemic stroke, emergency management and general stroke treatment, use of diagnostic tests in the acute phase, and the prevention and treatment of complications.

Acute Disease↗
PubMed2005

Prognostic significance of blood brain barrier permeability in acute hemorrhagic stroke.

BACKGROUND: Blood brain barrier (BBB) disruption is accompanied by edema in the surrounding areas of the intracerebral hemorrhage (ICH). The aim of the study was to clarify the correlation between BBB breakdown and outcome in ICH. PATIENTS: Twenty-seven patients with primary ICH were included in the study. Each patient underwent CT and DTPA-SPECT, and the National Institutes of Health (NIH) and modified Rankin score were performed as well. RESULTS: DTPA-SPECT had a significant correlation with the modified Rankin score after 3 months (p = 0.008) and 6 months (p = 0.01). The CT scan was directly correlated with the NIH score on days 1, 7 and 30 (p = 0.01, p = 0.01 and p = 0.04, respectively). No correlation was found between DTPA-SPECT and CT scan data. CONCLUSIONS: The degree of BBB breakdown, as imaged by the DTPA-SPECT technique, was directly correlated with the late functional outcome. The CT scan has an inverse correlation with the NIH score. These findings may have broad clinical implications.

Acute Disease↗
PubMed2005

Auditory hallucinations in acute stroke.

Auditory hallucinations are uncommon phenomena which can be directly caused by acute stroke, mostly described after lesions of the brain stem, very rarely reported after cortical strokes. The purpose of this study is to determine the frequency of this phenomenon. In a cross sectional study, 641 stroke patients were followed in the period between 1996-2000. Each patient underwent comprehensive investigation and follow-up. Four patients were found to have post cortical stroke auditory hallucinations. All of them occurred after an ischemic lesion of the right temporal lobe. After no more than four months, all patients were symptom-free and without therapy. The fact the auditory hallucinations may be of cortical origin must be taken into consideration in the treatment of stroke patients. The phenomenon may be completely reversible after a couple of months.

Acute Disease↗
PubMed2004

Pathological laughter as a symptom of midbrain infarction.

Pathological laughter is an uncommon symptom usually caused by bilateral, diffuse cerebral lesions. It has rarely been reported in association with isolated cerebral lesions. Midbrain involvement causing pathological laughter is extremely unusual. We describe three patients who developed pathological laughter after midbrain and pontine-midbrain infarction. In two patients a small infarction in the left paramedian midbrain was detected, whereas the third one sustained a massive bilateral pontine infarction extending to the midbrain. Laughter heralded stroke by one day in one patient and occurred as a delayed phenomenon three months after stroke in another. Pathological laughter ceased within a few days in two patients and was still present at a two year follow-up in the patient with delayed-onset laughter. Pathological laughter can herald midbrain infarction or follow stroke either shortly after onset of symptoms or as a delayed phenomenon. Furthermore, small unilateral midbrain infarctions can cause this rare complication.

Brain Stem Infarctions↗
PubMed2004

123I-FP-CIT SPECT imaging of dopamine transporters in patients with cerebrovascular disease and clinical diagnosis of vascular parkinsonism.

UNLABELLED: The purpose of our study was to prospectively evaluate the striatal uptake of 123I-labeled N-(3-fluoropropyl)-2beta-carbomethoxy-3beta-(4-iodophenyl)nortropane (FP-CIT) and the response to l-dopa therapy in patients with cerebrovascular disease (CVD) who develop clinical symptoms of vascular parkinsonism (VP). METHODS: Twenty consecutive patients who developed VP in the course of CVD were prospectively enrolled in the study. All patients had CT evidence of CVD (17 patients had lacunar infarcts, 3 patients had territorial strokes). The clinical stage of the patients was assessed using the Hoehn and Yahr scale, and the severity of the symptoms was measured using the Unified Parkinson's Disease Rating Scale score. Ten age-matched subjects were used as controls. SPECT was performed 180 min after injection of 185 MBq 123I-FP-CIT using a dual-head gamma-camera. The ratio of the mean specific-to-nonspecific striatal binding for the entire striatum, caudate, and putamen was calculated in all patients and compared with that of controls. Putamen-to-caudate binding ratios were compared as well. The response to therapy was compared between patients with normal and abnormal 123I-FP-CIT binding. RESULTS: No correlation was found between any of the clinical variables and response to therapy in patients with VP. Nine patients had normal striatal 123I-FP-CIT binding with no significant differences in striatal or subregional binding ratios compared with those of the controls. In contrast, 11 patients had significantly diminished striatal binding compared with that of controls (P < 0.001). Subanalyses showed significantly decreased binding in the caudate (P < 0.04 and P < 0.01 for the right and left caudate, respectively), diminished binding in the putamen (P < 0.04 and P < 0.01 for the right and left putamen, respectively), and a decreased putamen-to-caudate ratio on the right side (P < 0.001). The latter ratio was not significant on the left. Two of the 3 patients with territorial strokes had significantly diminished striatal 123I-FP-CIT binding in the hemisphere contralateral to the CT lesion. All 9 patients with normal scan findings had a poor response to L-dopa. Six of 11 patients with abnormal studies had no response to L-dopa, whereas 5 patients had a good response (P < 0.03). CONCLUSION: The diagnosis of VP cannot be accurately confirmed on the basis of clinical features alone because CVD may alter the typical presentation of PD. Functional imaging with 123I-FP-CIT is highly recommended in patients with CVD who develop symptoms of VP to confirm or exclude the existence of nigrostriatal dopaminergic degeneration. Identifying a subset of patients with reduced 123I-FP-CIT binding in the striatum is important for better treatment selection.

Aged↗
PubMed2003

Correlation of neuropsychological evaluation and SPECT imaging in patients with Alzheimer's disease.

BACKGROUND: Mini-Mental State Examination (MMSE) is a very useful tool for diagnosing changes in cognitive functions by the general practitioner or other medical staff who is not familiar with neuropsychological tests. On the other hand, HMPAO brain SPECT has been shown to have a high sensitivity to detect neurodegenerative processes, which lead to dementia. The correlation between both methods is unknown. We compared both methods in order to find a rational evaluation tool for the practitioner to obtain a higher efficacy and cost effective way of using both methods. PATIENTS AND METHODS: Fifty-one patients diagnosed as having Alzheimer's disease (AD) were examined. Each patient underwent MMSE analysis, as well as HMPAO brain SPECT. The severity of SPECT abnormalities was categorized into mild, moderate and severe. Statistical analysis was performed in order to evaluate the correlation between imaging findings and neuropsychological testing. RESULTS: Marginal inverse correlation was found between global MMSE SPECT imaging on right and left side (p = 0.05) and the left temporal region (p = 0.05). MMSE subgroup component of orientation was highly significantly inversely associated with SPECT imaging of right and left frontal region (p > 0.0001). The MMSE subgroup of immediate memory was significantly correlated to left and right temporal regions (p = 0.001 and p = 0.002 respectively). Age was not significantly correlated to global MMSE or any of its subtest components. CONCLUSION: MMSE score has no linear correlation to SPECT perfusion findings. In cases of abnormal orientation score subgroup SPECT imaging is not recommended. In most instances, a combination of both methods should be employed by the general practitioner for further evaluation of dementia.

Aged↗
PubMed2003

[Functional transcranial Doppler].

Transcranial Doppler is an ultrasonic technique, which demonstrates the blood flow velocity in the intracranial arteries. Functional Transcranial Doppler (fTCD) is a method of comparing the cerebral blood flow velocities of different arteries demonstrated simultaneously in both hemispheres. The examination is performed before and after fulfilling certain motor and sensory functions and execution of cognitive tasks. The rationale behind this method is discussed as it is applied in each of those functions. It must be stressed that there is a different role of the fTCD in the anterior vs the posterior circulation systems. Whereas many studies prove good efficacy with use of middle cerebral artery and anterior cerebral artery method, the role of the vertebrobasilar system method is unclear. In addition, although visual functions can be demonstrated well by examination of the posterior cerebral arteries, only few evidences of efficacy were published concerning vertebral and basilar artery functions. However, fTCD is useful, easy to perform and presents a very cost effective method for demonstration of cerebral blood flow changes during and after completing cognitive and motor tasks. The tests can be used in healthy persons, as well as in patients with neurological diseases and during rehabilitation period.

Blood Flow Velocity↗
PubMed2003

Correlation of 99mTc-DTPA SPECT of the blood-brain barrier with neurologic outcome after acute stroke.

UNLABELLED: We conducted a study on humans to determine whether quantitative evaluation of blood-brain barrier (BBB) breakdown using the (99m)Tc-diethylenetriaminepentaacetic acid ((99m)Tc-DTPA) SPECT technique at the peak time of stroke evolution can predict neurologic outcome. METHODS: Thirty consecutive patients with acute stroke of the middle cerebral artery occurring >24 h and <48 h before admission were included in the study. Each patient underwent a complete neurologic examination according to the Scandinavian stroke score at 72 h after the stroke (S1) and again at 30 d (S2). The difference between initial and late scores was calculated (Delta S) and used to evaluate the change in neurologic status. A CT scan was obtained on all patients to determine the volume of stroke. The integrity of the BBB was evaluated using (99m)Tc-DTPA brain SPECT. A quantitative index of BBB disruption was defined as the ratio of the mean counts/pixel in the infarcted region compared with the mean counts/pixel in the contralateral nonaffected hemisphere. SPECT perfusion imaging was also performed with (99m)Tc-hexamethylpropyleneamine oxime ((99m)Tc-HMPAO) at 24 h after the (99m)Tc-DTPA study. The relative perfusion in the infarct region was expressed as the percentage of contralateral perfusion. RESULTS: The mean (99m)Tc-DTPA disruption index was 6.8 +/- 6.9 (range, 1-26.2). Seven patients (23%) had no BBB disruption. Statistical analysis showed that the disruption index was negatively correlated with Delta S (r = -0.423, P < 0.02). A disruption index of <2.5 was associated with a significantly better neurologic outcome (mean Delta S, 17.5 +/- 9.5) compared with patients with an index of >2.5 (mean Delta S, -0.85 +/- 4.97, P < 0.0001) with a sensitivity of 95% and a specificity of 89%. S2 was significantly correlated with S1 (r = 0.738, P < 0.001) and with Delta S (r = 0.656, P < 0.001). Perfusion abnormalities on the (99m)Tc-HMPAO SPECT studies ranged between 12% and 90% (mean, 37.6% +/- 17.8%) compared with those on the contralateral nonaffected side. No correlation was found between (99m)Tc-HMPAO uptake and Delta S, infarct volume by CT, or disruption index. The CT volume measurements were negatively correlated with S2 (r = -0.560, P < 0.004) but not with Delta S. CONCLUSION: (99m)Tc-DTPA SPECT of the BBB combined with quantitative analysis in patients with acute stroke is significantly related to clinical outcome, with a distinct prognostic cutoff threshold of 2.5. The use of this radionuclide brain SPECT technique represents a unique application of conventional nondiffusible brain agents.

Adult↗
PubMed2002

Diagnosing brain death using the transcranial Doppler with a transorbital approach.

BACKGROUND: Transcranial Doppler is a sensitive instrument for the diagnosis of brain death. The guidelines for the determination of brain death include the demonstration of specific blood flow patterns in the anterior and posterior circulation systems. A limitation of this method is the frequent false finding of no flow, especially when using the transtemporal approach in older women. OBJECTIVE: To evaluate the efficacy of the transorbital approach in the diagnosis of brain death using transcranial Doppler. METHODS: A prospective controlled, diagnostic test study was performed. Transorbital, transtemporal, and transforaminal approaches were used. Fifty-seven patients (29 men and 28 women; mean +/- SD age, 68.2 +/- 12.1 years) with clinically determined brain death were examined. RESULTS: In 45 patients, oscillatory flow or systolic spikes were found in all approaches. In 4 patients, no flow was detected. In 6 patients, oscillatory flow or systolic spikes were found in 2 approaches, including the transorbital one. In 2 patients, a positive finding was demonstrated only using the transorbital approach. Using the transorbital approach, the percentage of positive findings with definitive diagnoses of brain death rose from 79% to 88%. CONCLUSION: The transorbital approach is a useful addition for the diagnosis of brain death, using the transcranial Doppler technique.

Adult↗