Toxic neuropathies generally result in length dependent axonal neuropathy with the exception of diphtheria and a few toxic neuropathies. In spite of occurrence of diphtheria in India there is paucity of published reports on diphtheritic neuropathy. Arsenic neuropathy commonly occurs in Bengal and Bangladesh because of ground water contamination whereas in Punjab it is due to contamination of opium. Lead neuropathy is rare and has been reported in battery workers and silver refining workers. It produces motor neuropathy resulting in foot drop and wrist drop. Organophosphates are used as pesticides, industrial chemicals and food adulterant. Certain organophosphates such as triorthocresyl phosphate used for or oil adulteration inhibit neurotoxic esterase and result in a delayed type of axonal neuropathy. Alcohol related neuropathy is a controversial issue whether it is due to alcohol related toxicity or due to nutritional deficiencies. Indian studies have revealed that neuropathy occurs both in alcoholic and nonalcoholic cirrhosis. Hexane neuropathy is reported in screen printers and these cases highlight the need for better preventive and occupational measures. Iatrogenic toxic neuropathies have been reported with cisplatin and vincristine. Because of geographical, occupational and health related conditions toxic neuropathies are likely to be more common than reported and greater awareness is needed.

The nearly absent ability of the neurons to regenerate or multiply has prompted neuroscientists to search for the mean to replace damaged or dead cells. The failed attempts using adult tissue, initiated nearly a century ago, ultimately brought rays of hope when developing fetal neurons were used for transplantation in 1970s. The initial excitement was tempered by limited success and ethical issues. But these efforts unequivocally established the feasibility of successful neural transplantation provided appropriate tissue was available. The ability to derive embryonic stem cells with their totipotent potential by Thomson in 1998 rekindled the interest in their use for replacement therapy for damaged brain tissue. The present review surveys the current status of this promising field of stem cell research especially in respect to their therapeutic potentials for purposes of neural transplantation. A brief account is provided of the ongoing Indian efforts in this direction.

Pedicle screws are widely used for instrumentation of the thoracolumbar spine. The anatomic studies performed in the last two decades, detailing the complex morphometry and three-dimensional anatomy of the thoracolumbar pedicles, have enabled the emergence of the so-called "free-hand" technique of pedicle screw placement based exclusively on anatomical parameters. However, in the thoracic spine, the benefits of pedicle screws have been tempered by its potential risks, such as, spinal canal violation, pedicle fracture, nerve root compression, and vascular lesions. Furthermore, the narrow and inconsistent shape of the thoracic pedicles, especially in spinal deformity, makes their placement technically challenging. In this article, the authors make a critical appraisal of current "state-of-art" of "free-hand" technique of pedicle instrumentation, analyzing its anatomical basis, surgical technique, present indications and limitations as well as the role of adjuvant image-guided and neurophysiological monitoring methods.

Background : Traumatic brain injury (TBI) is an important cause of adult mortality and morbidity. Erythropoietin (Epo) has been shown to promote the viability of cerebral cells by upregulating Bcl-2 gene; however, Epo may exert its antiapoptotic effect via the differential regulation of the expression of genes involved in the apoptotic process. Aim : The present study examined the neuroprotective effect of Epo as a survival factor through the regulation of the Bax. Materials and Methods : Wistar rats were randomly divided into three groups: Recombinant human EPO treated (rhEPO) TBI, vehicle-treated TBI, and sham-operated. Traumatic brain injury was induced by the Feeney free-falling model. Rats were killed 5, 12, 24, 72, 120, or 168 h after TBI. Regulation of Bcl-2 was detected by reverse transcription-polymerase chain reaction (RT-PCR), western blotting and immunofluorescence. Results : Bax mRNA and protein levels were lower in the rhEPO)-treated rat brains than in the vehicle-treated rat brains. Induction of Bax expression peaked at 24 h and remained stable for 72-120 h in vehicle-treated rat brains, whereas induction of Bax expression was only slightly elevated in rhEPO-treated rat brains. The number of TdT-mediated dUTP Nick-End Labeling(TUNEL)-positive cells in the rhEPO-treated rat brains was far fewer than in the vehicle-treated rat brains. Conclusions : Epo exerts neuroprotective effect against traumatic brain injury via reducing Bax gene expression involved in inhibiting TBI-induced neuronal cell death.

Background : Restless leg syndrome (RLS) has negative effects on the quality of life of the patients. Epidemiological studies on RLS are limited. Aim : To determine the prevalence of RLS among people aged 40 years and above in Orhangazi district of Bursa, Turkey. Materials and Methods : The study was carried out between 2004 and 2005. This population-based study was conducted in two phases. In the phase 1, residents conducted door-to-door interviews using a short questionnaire to determine the possible cases of RLS. In the phase 2, physicians ascertained the suspected cases of RLS. Diagnosis of RLS was made using the criteria proposed by the International Restless Legs Syndrome Study Group (IRLSSG) and also the rating scale for RLS. Results : Out of 1, 256 subjects screened in phase 1, 1,124 (89.6%) were included in the study. Also, 161 cases with suspected symptoms of RLS were detected in phase 1, 49 of the suspected cases could not be evaluated in phase 2. A diagnosis of RLS was also made in 60 cases during phase 2. Conclusions : We defined the prevalence of RLS as 9.71% among 40 years of age and older population. The prevalence of RLS did not differ by age and was 2.6 times more in women. None of the patients were diagnosed as RLS sought medical care for the symptoms, possibly due to lack of knowledge of patients and physicians about RLS. Prevalence studies help to provide knowledge on morbidity, which is essential for diagnosis and early treatment.

Background : Duchenne muscular dystrophy (DMD) is the most common muscular dystrophy that affects young boys and the dystrophin gene on the X chromosome has been found to be associated with the disorder. Materials and Methods : In this prospective study, 112 clinically diagnosed DMD patients had muscle biopsy and were tested for exon deletions. Genotyping was also carried out at STR44, STR45, STR49 and STR 50 markers in 15 families. Results : Of the 112 clinically suspected DMD patients, the diagnosis of DMD was confirmed by histopathology and/or genetics in 101 patients. The mean age of onset was 3.1±1.44 years (1-6 years) and the mean age at presentation was 8.0±3.1 years (1.1-18.0 years). Delayed motor milestones were present in 63 (62.3%) patients. The mean creatine kinase value was 11822.64±8206.90 U/L (1240-57,700). Eighty-four patients had muscle biopsy and immunohistochemistry was done in 60 muscle samples, all of which demonstrated absence of dystrophin staining. Of the 60 dystrophin-negative cases, 73% showed deletion of at least one exon. Single exon deletion was found in 20.4%. Distal hotspot Exons 45, 47, 49 and 50 were the commonly deleted xenons and the deletion rates were 36%, 35%, 33.7% and 38.5% respectively. Conclusions : In this study population in south India the deletion rate was 73% and were more frequent in the distal end exon. With the availability of genetic analysis, the first investigation of choice in DMD should be genetic studies and muscle biopsy should be considered only if the genetic tests are negative or not available.

Background : In patients with acute stroke receiving intravenous tissue plasminogen activator (tPA), we postulated that the presence of intracranial occlusion on CT angiography (CTA) modifies the benefit of thrombolysis. Materials and Methods : Using a retrospective cohort design, we identified patients with acute ischemic stroke in our CTA database between May 2002 and August 2007. All the patients had a CTA within 12 h of onset, a premorbid modified Rankin scale (mRS) #1, and a baseline National Institute of Health Stroke Scale score(NIHSS)f $6. The primary outcome was early effectiveness of tPA defined as an NIHSS score of #2 at 24 h or a 4-point NIHSS improvement at 24 h. Secondary outcome included mRS #1 at 90 days. The relationship between intracranial occlusion on CTA and benefit of tPA was assessed using a test for interaction. Results : A total of 287 patients met the criteria [occlusion present N =168; (98 with tPA; 70 without tPA) and occlusion absent N = 119; (52 with tPA; 67 without tPA)]. Those with intracranial occlusion were likely to have more severe strokes (NIHSS $15; P < 0.001) and abnormal brain imaging (ASPECTS #7; P < 0.001). For outcome of 4-point NIHSS score improvement at 24 h, benefit from tPA was observed only among patients with a visible occlusion (absolute difference in favor of tPA: 20.4% vs. 0.7%; P = 0.06). Conclusion : In patients with acute ischemic stroke, thrombolysis produced a better early clinical response among patients with intracranial occlusion, which needs to be confirmed in stroke thrombolysis trials.

Background : Meningiomas are presently categorized into three grades by World Health Organization (WHO). Grade I, in general, is expected to behave in a benign fashion. However, a borderline group of grade I meningioma also exists, which may behave aggressively. Aims and Objective : To evaluate the proliferation index and p53 antigen expression of meningiomas and correlate with histological grade and clinical course. Materials and Methods : All 123 cases of meningiomas, diagnosed between January 2000 and August 2007, were regraded according to WHO 2000 criteria. Immunostaining for Ki-67 antigen and p53 protein were performed on 68 cases selected for the study. Results : Six of the 68 cases presented with recurrence. Mean Ki-67 labeling index (Ki­67 LI) was 3.8%, 13.7%, 19.4% for grade I, II, and III cases, respectively. Multivariate analysis of mean Ki-67 LI showed statistically significant difference between subgroups. Mean p53 expression was found to be 15.5%, 57%, 60.8%, and 62.5% for grade I, II, III, and recurrent cases, respectively. Multivariate analysis of mean p53 expression showed no statistically significant difference between higher grades. All recurrent cases were histologically WHO grade I, and showed a high Ki-67 LI and p53 expression with mean Ki-67 LI and p53 expression of 8.6% and 62.5% respectively. Conclusion : Utilization of markers for proliferation and cell cycle regulators in combination with histopathological features helps in the identification of a subset of biologically aggressive morphologically benign meningiomas.

Background : Intracranial arteriovenous malformations (AVM) are being increasingly managed by multimodality approach. This changing scenario encouraged us to study the present state of surgery in intracranial AVMs and the outcomes. Materials and Methods : Of a total of 868 patients evaluated for suspected or known AVMs between January 2000 and July 2008, 790 had intracranial AVMs. The clinical characteristics and surgical outcomes of the 111 opeated patients were analyzed. Results : Of the 111 patients, 73 were males. Clinical features included: Headache (70%), loss of consciousness (48%) and seizures (32%). The commonest AVM grade was Spetzler-Martin (SM) grade II (41%), 7% had AVM >6 cm and 78% had evidence of bleed. In total 143 surgeries were performed and 22% of patients required multiple interventions. The types of surgical interventions included elective excision of AVM in 23%, emergency surgery (either AVM excision or evacuation of hematoma) in 55%, surgery following radiosurgery/embolization in 5% and palliative non-definitive surgeries (e.g. shunt) in 15%. Post-operative angiography was done in 67% of patients. Obliteration rates for elective excision of AVM in Spetzler Martin Grade I, II, IIIa, IIIb and IV were 100%, 71%, 33%, 50% and 67% respectively (mean follow-up:31.6 months). Of 39 patients with residual AVMs, 33 received gamma knife and four underwent embolization. Outcome was modified Rankin scale (mRS) grade 1 in 34% of paitnets and the overall favorable outcome was 83% and there were six deaths. Conclusion : In our patients' cohort one in every eight patients required surgery. In intracranial AVMs, surgery still plays an important role. In developing countries like India it may be beneficial to electively excise Grade I and II AVMs if cost is a consideration.

Background : Primary central nervous system (CNS) lymphoma (PCNSL) is a rare malignant non-Hodgkin's lymphoma and it accounts for 1% of all intracranial tumors. Only a few PCNSL studies have been reported from India, and studies on prognostic factors determining outcome, or evaluation of the response to currently accepted treatment, are lacking. Aims : This study attempts to further delineate the clinical, radiological and pathological profile of PCNSL in India, to evaluate response to treatment and to assess usefulness of the International Extranodal Lymphoma Study Group (IELSG) score. Settings and Design : All patients with pathologically proven PCNSL admitted over three years at a large tertiary care institution were studied. Materials and Methods : Clinical features, IELSG prognostic score, imaging and pathological features, and response to treatment were evaluated. Results were analyzed using χ ² test. Results : Of 26 patients found, all except two were immunocompetent. Median age at diagnosis was 59 years. Focal deficits (76.9%) and neuropsychiatric symptoms (57.6%) were the commonest presenting complaints. Except for one case, at least some contrast enhancement was seen in brain lesions of all patients. Pathological studies showed high grade diffuse large B-cell (DLBCL) histology in 96.2% of patients. Of 22 patients who received methotrexate (MTX) based chemotherapy with/without radiotherapy; six died, with a response rate of 72.7%. Median survival was 10 months. Median follow-up duration was 14.5 months. Four patients developed treatment-related cognitive decline. All six patients with IELSG score of 4/5 died, while all 16 patients with a score of 0-3 survived. Conclusions : PCNSL presents most commonly in the sixth decade with focal neurological deficit, behavioral symptoms and cognitive decline. High grade DLBCL is the commonest histological subtype. Steroids should ideally be withheld until biopsy as they may confound the diagnosis. Most immunocompetent patients respond well to high dose MTX-based chemotherapy with/without radiation. High IELSG scores correlate with worse prognosis in patients with PCNSL

Intra-arterial thrombolysis (IAT) is a treatment modality in patients with acute large vessel occlusive ischemic stroke. To our knowledge, this is probably the first reported study of intra-arterial thrombolysis in acute ischemic stroke from India. Of the 17 patients treated who recieved IAT, successful recanalization was achieved in nine patients, Thrombolysis in Myocardial Infarction (TIMI) score of 2 or 3. At 90-day follow-up, eight patients achieved modified Rankin Scale (mRS) score of <2.

One of the prominent disturbances in Parkinson's disease (PD) is bradykinesia. We studied performance of hand-to-mouth reach reaction time (RT) in right-handed PD patients and nine age and sex matched healthy control subjects. Participants practiced hand-to-mouth reach skill in response to a visual stimulus, 120 times a day for a period of one week. Using Kinemetrix 3D Motion Analysis system, the effects of motor skill practice and learning retention were investigated. Pretest performance was compared with performances on the second and seventh day of the study, and also performance on fourteenth day with no further practice for one week. There was a significant reduction in the mean RT in the control group after one week of practice. In PD patients the reduction in the mean RT was significant between pretest and first test sessions (P < 0.01). However, the difference was not significant between the first and second session (P = 0.06) and also between the second and third test sessions (P = 1.0). Short-term practice can improve bradykinesia in patients with PD but it is not long-lasting.

Meningiomas associated with intracranial aneurysms are very rare. The co-existence of both lesions is not only a diagnostic challenge but also has important therapeutic implications. We analyzed our experience of five such patients, the second largest group in the literature. All the lesions were successfully managed surgically. All the patients were female. The location of the meningioma was clinoidal (2), planum sphenoidale (1), petroclival (1) and pterional (1). Three patients had posterior communicating (PCOM) artery aneurysm associated with meningioma. The other aneurysms were internal carotid artery (ICA) and anterior communicating artery (ACOM). One patient with pterional meningioma had an anomalous meningeal artery arising from the right ophthalmic artery. In three patients both lesions underwent treatment at the same sitting. In two patients meningioma underwent excision first followed by aneurysm clipping. From our experience the incidence of meningiomas associated with aneurysms was 1.1%, which is not higher than the incidence of aneurysms in the general population.

Background: The retrosigmoid approach is a common route to the cerebellopontine angle and lateral clivus. Patient's head positioning just before the operation is crucial to perform the procedure effectively and safely. Aim : The aim of the study is to determine the positional angle of the head on preoperative axial sequences of the cranial magnetic resonance imaging (MRI). Materials and Methods : The angle between the line drawn along the petrous bone ventral to the internal auditory canal and the line drawn parallel to the dorsal face of the clivus on the axial view of MRI sequences was measured. Results : This method of patient positioning has resulted in minimal cerebellar retraction, less time in the preoperative preparation period and less postoperative headache and neck pain. Conclusions : This method can provide quick and better exposure of the cerebellopontine angle. Preoperative measurement of positional angle on axial MRI sequences is a very simple and sufficient way to determine the angle of the head that is turned to the contralateral side.

A 59-year old man developed perioperative stroke following left carotid endarterectomy seconday to thrombosis at the endarterectomy site. Transcranial Doppler ultrasonography revealed very frequent microembolization in the left middle cerebral artery territory. The patient was successfully treated with intravenous abciximab with complete neurological recovery.

Bell's palsy is a peripheral facial palsy of sudden onset. The etiology of Bell's palsy is unknown and hereditary components may play a role in familial recurrent Bell's palsy. We report three families in which eight patients had a total of 12 episodes of typical Bell's palsy. The pathophysiology of familial recurrent Bell's palsy is discussed.

The coexistence of a cerebral and a spinal arteriovenous malformation (AVM) together is extremely rare. We present a 31-year-old woman, who suffered from severe root pains in the left upper extremity. Magnetic resonance imaging (MRI) revealed the abnormal vessels in the left occipital lobe and upper cervical segment of spinal cord. Cerebral angiography and spinal angiogram revealed two AVMs: One was in the right occipital lobe and the other was located in the C1-C2 segments of cervical cord. She had no other vascular lesions, and nor did her other family members. As the primary problem in her was left upper extremity root pains, which we considered was related to the spinal AVM, the first therapeutic treatment was focused on spinal AVM. The cerebral AVM of the right occipital lobe was surgically resected after part embolization.

Both akinetic and hyperkinetic movement disorders may rarely be the presenting feature of human immunodeficiency virus (HIV) infection. The possible pathogenic basis is the involvement of subcortical structures by the HIV infection-related pathology. Opportunistic infections, or mass lesions complicating HIV infection. In addition dopaminergic dysfunction and medications may also play a role. We report a HIV infected male who presented with progressive choreoathetoid movements and dystonia. He had remarkable improvement of the movement disorder with tetrabenazine and anti-retroviral therapy (HAART) treatment.

Papillary glioneuronal tumor (PGNT) is a newly described mixed glioneuronal tumor, recently included in the World Health Organization classification of central nervous system tumors. We report morphologic and immunohistochemical characteristics PGNT of the pineal region extending into the third and lateral ventricles in a four-year-old male child and reviewed all the cases reported in the international literature till date. In this child the diagnosis of PGNT was established by endoscopic biopsy and squash smear examination.

Desmoplastic infantile gangliogliomas (DIGG) are low-grade (WHO Grade I) tumors of early childhood rarely occurring in older children and young adults. The mainstay of treatment is surgical. We report two older children with DIGG, both showing atypical radiology. One case was treated with radiation. The recurrence treated with only surgical excision showed excellent response to treatment.

Giant parenchymal cysticercosis is a relatively rare condition and surgical treatment may be required when it is associated with elevated intracranial pressure. We report two patients with giant parenchymal cysticercosis who were treated surgically for the elevated intracranial pressure. In both the patients the preoperative diagnosis was of a cystic glioma. Total excision of the lesions was achieved in both the patients. In countries endemic to neurocysticercosis gaint parenchymal cysticercosis should be considered in the differential diagnosis of cystic enhancing mass lesion. Surgical excision may be indicated when it is associated with elevated intracranial pressure.

Anterior cervical location of arachnoid cyst is a rare and only 22 cases have been reported in the literature. The surgical approach was quite varied and mostly these cysts were accessed via dorsal laminectomy, with few patients developing postoperative neurological deficit. We report a 51-year-old male with a cervical arachnoid cyst extending from the dens to the inferior border of the C3 body, which was successfully decompressed via an anterior cervical approach through the partial corpectomy of C2. This is probably the first case report demonstrating the safety of anterior partial median corpectomy of the C2 body with micro discectomy of C2-C3 space for excision of the anterior cervical archnoid cyst. The additional advantage of this procedure is that it may not result in spinal instability.