Interhemispheric subdural hematoma: an uncommon sequel of trauma.

Interhemispheric subdural hematomas are relatively uncommon and usually seen in patients with bleeding disorders. They may present with signs of the falx syndrome or seizures. The management options range from craniotomy and evacuation to conservative management. We report such a case in a patient with normal bleeding parameters, which was managed with a twist drill craniostomy and drainage of the hematoma.

Hemorrhagic necrosis of pituitary adenomas.

A clinicopathological study of 41 cases of pituitary apoplexy in a series of 324 surgically treated pituitary adenomas is presented. In 23 patients, the predominant operative finding was hemorrhage with or without necrosis. However, there were 15 (37.7%) cases where pale, necrotic tissue with no evidence of hemorrhage was found at surgery. Pale, necrotic material was particularly found when there was a long interval between the acute clinical event and surgery. It is concluded that the pale, necrotic debris represents one stage in the resorption process of blood after hemorrhagic necrosis of pituitary adenomas. This entity needs to be kept in mind especially since the material closely resemble the pultaceous material seen in craniopharyngiomas and epidermoid cysts.

Management of symptomatic vertebral hemangiomas: review of 13 patients.

Thirteen consecutive cases with symptomatic vertebral hemangiomas, managed during a five year period from January 1995 at the Christian Medical College and Hospital, Vellore, were analysed. Twelve patients had lesions in the thoracic and 1 in the sacral region. Eight patients had multiple level involvement. Seven patients had laminectomy and soft tissue component excision, of which one had intraoperative injection of absolute alcohol and one had postoperative radiotherapy. One patient had vertebrectomy and stabilization with preoperative embolization. One patient underwent only endovascular embolization. However, the focus of this communication is on 4 patients who underwent a CT guided percutaneous transpedicular injection of absolute alcohol into the affected vertebral body. In the surgical group, 6 patients had cavernous type and 2 patients had mixed type of hemangiomas. Ten patients improved on the Ranawat grade by the time of discharge. On the MRC grade, 11 patients had improved, one was grade 5 pre and postoperative, while one did not improve. Several options are available for the management of symptomatic vertebral hemangiomas and multiple modalities may have to be used for a single patient. CT guided percutaneous transpedicular injection of absolute alcohol shows promising results. However, long term follow up is mandatory.

Transsphenoidal line of vision on MRI for pituitary tumor surgery.

This study was done to determine the usefulness of the sagittal magnetic resonance image (MRI) in predicting the ease of resectability of pituitary adenomas operated through the transsphenoidal route. Tumors were graded according to Hardy's method and a new system proposed by us. In this system the amount of tumor above the line of vision (V-line) as seen on the sagittal MRI was estimated and correlated with the extent of excision assessed on the postoperative computed tomogram (CT). There were 7 Hardy's grade A (8.8%), 32 grade B (41.3%), 31 grade C (37.5%), 6 grade D (8.8%) and 2 grade E tumors (3.8%) among the 78 tumors studied. It was seen that most of the tumor volume was below the V-line in Hardy's grade A and B tumors. In grade C tumors 5 were < 25% above, 14 were 25-50% above and 12 were 50-75% above the V-line. A radical excision was possible in 15 of l9 grade C tumors in which < 50% of the tumor was above the V-line. However, only 5 of 12 with Hardy's grade C were radically excised when >50% of the tumor was above the V-line. In conclusion, Hardy's grade C tumors are not a homogenous group radiologically and using the V-line on MRI helps in predicting the case of respectability in a single stage.

Midbrain venous angioma with obstructive hydrocephalus.

A rare case of a mid brain venous angioma with obstructive hydrocephalus is described. A dilated draining vein from the lesion in the aqueduct as the cause of the hydrocephalus is highlighted, and interesting features of the pathology of venous angiomas and associated cavernous hemangioma are described. The management of this interesting condition is discussed.

Quantitative study of muscle spindles in suboccipital muscles of human foetuses.

The proprioceptive inputs from the cervical musculature play an important role in head-eye co-ordination and postural processes. Deep cervical muscles in humans are shown to have high spindle content. The density, distribution and morphology of muscle spindles were studied in superior oblique capitis, inferior oblique capitis and rectus capitis posterior major and minor three small suboccipital muscles. The muscles were obtained, post-mortem from stillborn human foetus. The spindle density was calculated as the ratio of mean spindle content to the mean wet weight of that muscle in grams. The distribution and arrangement of spindles within the muscle and their arrangement was studied. The spindle density of superior oblique muscle was found to be 190, that of inferior oblique was 242 and the rectus capitis posterior contained 98 spindles per gram of muscle. No tendon organs were seen. The serial transverse sections of inferior oblique muscle revealed muscle spindles of varying sizes, length varying between 100-650 microns and, diameter 50-250 microns. A complex parallel arrangements of group of large spindles were seen in the belly of the inferior oblique muscle, while the polar regions contain few small isolated spindles. The relevance of such high spindle receptor content in these tiny muscles is discussed.

Motor and somatosensory evoked potentials in a primate model of experimental spinal cord injury.

Motor and somatosensory evoked potentials (MEP and SSEP) were compared after experimental spinal cord injury in Bonnet monkeys (macaca radiata). The MEP and SSEP changes following graded injuries were related to clinical outcome. Eight healthy mature monkeys with a mean weight of 4.2 + 0.9 Kg were chosen for the study. Graded spinal cord injury was caused using 50, 100, 200, 300 gm-cm force by modified Allens' weight drop device. MEP and SSEP recordings were done before injury and at 0, 2, 4 and 6 hours after injury and on the 7th postoperative day. Neurological assessment was done at 24 hours and on the 7th day following injury. 50, 100, 200 gm-cm force caused partial injuries and 300 gm-cm force caused severe spinal cord injury. The predictive value of MEP and SSEP following partial injuries was 80% and 66.67% respectively. Both MEP and SSEP were 100% predictive in severe injury. MEP and SSEP monitoring can therefore be complementary to each other in predicting the neurological outcome in partial injuries to the spinal cord.

Determination of Ki-67 labeling index in pituitary adenomas using MIB-1 monoclonal antibody.

Proliferative activity of 94 pituitary adenomas was assessed by the determination of the growth fraction, using MIB-1 monoclonal antibody in formalin fixed, paraffin embedded sections. This index was correlated with clinical and radiological evidence of invasiveness. The mean Ki-67 labeling index for all pituitary adenomas was 0.84% (range 0-17.45%). Hardy stage E tumours (1.44%) had a higher Ki-67 labeling index (LI) as compared with Hardy stage 0 tumours (0.36%). The difference in the Ki-67 labeling indices between invasive and non-invasive adenomas was not statistically significant. Hence, the Ki-67 labeling index is not a reliable indicator of invasiveness in pituitary adenomas.

Effect of dichloracetate on infarct size in a primate model of focal cerebral ischaemia.

Acidosis is a major contributing factor towards spread of the ischaemic focus in the brain. Drugs that increase pyruvate dehydrogenase activity could decrease the formation of lactic acidosis. The sodium salt of dichloracetic acid (DCA) has been found to be effective in reducing lactate. This study was undertaken to study the efficacy of DCA in reducing infarct size in experimental focal ischaemia in monkeys. Macaca radiata monkeys in the treatment group were given 35 mg per kilogram of dichloracetate intravenously immediately before occluding and interrupting the middle cerebral artery, and the control group was given saline as placebo under similar conditions. Mean infarct size expressed as a percentage of the size of the hemisphere in all the three brain slices was 35.38 in the control group as against l2.06 in the treated group (p=0. 0008).

Central nervous system toxoplasmosis in acquired immunodeficiency syndrome: An emerging disease in India.

With the incidence of patients infected with human immuno-deficiency virus (HIV) increasing in India, the central nervous system (CNS) manifestations of the disease will be seen more frequently. The CNS may be primarily afflicted by the virus or by opportunistic infections and neoplasms secondary to the immune suppression caused by the virus. In India, although mycobacterium tuberculosis has been reported to be the most common opportunistic infection, toxoplasmosis may become as common owing to the ubiquitous nature of the protozoan. Since an empirical trial of medical therapy without histopathological diagnosis is recommended, the true incidence of this condition may remain under estimated. The role of ancillary tests such as radiology and serology in the initial diagnosis of this condition remain crucial. This report highlights two patients who were diagnosed to have acquired immuno-deficiency syndrome (AIDS) only after the biopsy of the intracranial lesion was reported as toxoplasmosis. Presently all patients for elective neurosurgery are tested for HIV antigen. The management protocol to be followed in a known patient with AIDS presenting with CNS symptoms is discussed in detail. The value of ancillary tests is also reviewed.

Management of intramedullary spinal cord tumours: review of 68 patients.

68 consecutive patients admitted with intramedullary spinal cord tumours and operated at Vellore during a six year period from January 1990 are discussed. 41 tumours were radically resected, 11 partially excised while 14 had only a biopsy. Radiation therapy was advised post operatively to those patients for whom a partial excision or biopsy was done. There was no postoperative mortality. Two patients developed wound infection and one developed postoperative hydrocephalus. Postoperative clinical assessment between four to eight weeks after surgery showed that 25 out of 68 patients improved, 29 remained unchanged, while 14 had worsening of deficits. Immediate post operative assessment, however, was less encouraging. Evaluation of these patients was done using a functional scoring system and Karnofsky rating. The follow up period ranged from 2 weeks to 64 months after discharge from hospital with a mean of 14.6 months. The indicators of radical excision were good tumour-cord interface, cranially located tumours, presence of syringomyelia and histology of ependymoma. Two patients had recurrence of tumour.

Epilepsy surgery : overview Of forty years experience.

Although many patients with epilepsy achieve control of their seizures with medication, a substantial number ultimately develop intractable epilepsy. Patients with intractable epilepsy form the group for whom surgical procedures may be beneficial. We retrospectively analyzed the clinical profile and outcome of 141 patients operated for intractable epilepsy at Vellore between 1949 and 1990. The operative procedures done for suprasylvian epilepsy were topectomy (24 cases) and lobectomy (2 cases). For temporal lobe epilepsy the surgical procedures done were topectomy (28 cases), temporal lobectomy with amygdalectomy (25 cases), temporal lobectomy with amygdalectomy and hippocampectomy (10 cases), amygdalectomy (15 cases) and topectomy with amygdalectomy in one case. Hemispherectomy was done for 12 cases with multilobe epilepsy. For multifocal epilepsy, four patients underwent stereotactic ansotomy. Post operative complications included infections (10 cases) and acute post operative haematoma in one patient. There was transient neurological deterioration in ten patients. Three patients operated prior to 1960 died due to peri operative complications. Follow up data of 80 patients, ranging from 1 to 42 years (mean 10 years) was analysed. Total or near total seizure control was obtained in 53% patients and a worthwhile outcome in 20% patients. Mental retardation, pre operative scalp electroencephalography and post excision electrocorticography has been shown to be predictors of outcome with respect to seizures.

Medullomyoblastoma: A case report.

Medullomyoblastoma is a rare tumour seen in childhood. We report a medullomyoblastoma occurring in the cerebellar vermis of a 4 year old boy. The light microscopic features, immunohistochemistry and histogenesis are described.

Sacral nerve root cysts: A review on pathophysiology.

Nerve root cysts of the sacral region are generally asymptomatic but are known to cause neurogenic claudication. In this paper we present an elderly lady who presented with claudication, whose MR imaging showed a sacral cyst. She underwent lumbo-sacral laminectomy, partial excision of the cyst wall with plication. A review of the possible pathophysiology of such a lesion is discussed.

Changes in phospholipids and acetylcholinesterase during early phase of injury to spinal cord--an experimental study in rats.

Injury to spinal cord was produced in rats by the clip compression technique by placing the aneurysm clip extradurally for 30 seconds. The traumatised spinal segment and the adjoining upper segment were used for biochemical estimations. Motor function of the injured rats was evaluated using the inclined plane. Phospholipid phosphorus values were significantly decreased in the injured spinal segment at 24 hrs. AchE activity was also decreased in the traumatised segment one week after injury. Dexamethasone and verapamil reversed the changes in AchE activity at the end of one week. At the one week assessment period, aneurysm clipped rats showed a decrease in the maximum angle in the inclined plane. Dexamethasone and verapamil treated rats showed improvement in the neurologic function, neurologic recovery was better in the dexamethasone treated group.

Melioidosis In India: the tip of the iceberg?

Diagnosis of melioidosis by the isolation of Burkholderia pseudomallei from one or more body fluid/tissue specimens of 6 Indian subjects, 5 of whom had not travelled outside India, is reported. The places of residence of these 6 and one patient previously reported, namely Tripura (2), Kerala (2), Orissa (1), Tamil Nadu (1) and Maharashtra (1) are therefore potentially endemic for melioidosis. B.pseudomallei closely resembles common contaminant Pseudomonas sp. and are easily mis-identified in microbiology laboratories. We surmise that melioidosis is underdiagnosed and underreported in India and we alert clinicians, microbiologists and public health professionals to the possibility of melioidosis being far more common than previously recognised.