Hydrocephalus is a common complication of tuberculous meningitis. Case studies of 114 patients with tuberculous meningitis and hydrocephalus, who underwent shunt surgery between July, 1975, and June, 1986, were reviewed to evaluate the long-term outcome and to outline a management protocol for these patients based on the results. Seven factors were studied in each case: 1) age at admission; 2) grade on admission (I to IV, classified by the authors; Grade I being the best and Grade IV being the worst); 3) duration of alteration of sensorium; 4) cerebrospinal fluid (CSF) cell content at initial examination; 5) CSF protein levels at initial examination; 6) number of shunt revisions required; and 7) the necessity for bilateral shunts. During a long-term follow-up period ranging from 6 months to 13 years (mean 45.6 months), the mortality rate was 20% for patients in Grade I; 34.7% for patients in Grade II; 51.9% for patients in Grade III; and 100% for patients in Grade IV. Only the grade at the time of admission was found to be statistically significant in determining final outcome (p less than 0.001). Based on these results, the authors advocate early shunt surgery for Grade I and II patients. For patients in Grade III, surgery may be performed either if external ventricular drainage causes an improvement in sensorium or without selection. All patients in Grade IV should undergo external ventricular drainage and only those who show a significant change in their neurological status within 24 to 48 hours of drainage, should have shunt surgery.

It is commonly believed that differentiating solitary small cysticercus granulomas and small tuberculomas in patients with seizures is difficult without resorting to an excision biopsy. The aim of this study was to formulate clinical and computerized tomography (CT) criteria to distinguish these two entities in patients with epilepsy. Toward this end, clinical and CT data from six consecutive patients with histologically proven small solitary tuberculomas and 25 consecutive patients with histologically proven solitary cysticercus granulomas were compared. Evidence of raised intracranial tension and a progressive focal neurological deficit was seen only in patients with tuberculomas (two of six cases). All tuberculomas were greater than 20 mm in size and five of the six were irregular in outline. Only tuberculomas were associated with a midline shift on CT (four of six cases). All cysticercus granulomas were less than 20 mm in size and 24 (96%) of the 25 were regular in outline, conforming to one of two characteristic patterns. No cysticercus granuloma was associated with a midline shift. Based on the above clinical findings (evidence of raised intracranial tension and a progressive neurological deficit) and CT criteria (size, shape, and association with a midline shift), it is possible to separate these two entities in a majority of patients with seizures and with a single small lesion on CT.

The benefits of the use of computerized tomography (CT)-guided stereotactic surgical techniques for the management of intrinsic brainstem masses diagnosed from clinical evaluation and imaging studies were evaluated vis-à-vis the risks involved in 71 consecutive patients. Seventy-two procedures were performed. The masses were diffuse, involving two or three contiguous brainstem segments, in 60 patients and focal in 11 patients. On the CT scans, 25 patients had hypodense nonenhancing masses, two had isodense nonenhancing masses, 19 had ring-enhancing masses, and 25 had heterogeneously enhancing masses. A positive biopsy was obtained in 68 of 69 patients (98.5%) undergoing a biopsy procedure. In nine patients (12.6%) with suspected malignant masses a benign pathology was diagnosed (four tuberculomas, two epidermoid cysts, one pyogenic abscess, one epidermal cyst, and one case of encephalitis). Additionally, fluid from cystic masses could be aspirated in eight cases, providing benefit in six (four patients had benign lesions and two had neoplastic lesions). Thereby, a total of 13 patients (18.3%) were deemed to have benefited from the surgery (two patients were included in both categories). Patients with focal masses and ring-enhancing masses had the highest proportion of benign lesions (60% and 36.8%, respectively) and therefore derived the most benefit from histological verification. There was no procedure-related mortality. One patient (1.4%) suffered permanent morbidity and four others (5.6%) had transient worsening attributable to the procedure. The authors conclude that CT-guided stereotactic surgery of the brainstem is safe and reliable. Histological verification of all enhancing (especially ring-enhancing) and focal brainstem masses should be undertaken to identify patients with benign nonneoplastic lesions. Selected patients with diffuse hypodense nonenhancing masses with atypical clinical or imaging features may also benefit from stereotactic biopsy. Even in these patients the lack of enhancement on a contrast-enhanced magnetic resonance image, rather than the diffuse location of the tumor alone, should form the basis for diagnosing a malignant glioma. The main value of stereotactic surgery lies in the identification of benign masses in a significant proportion of patients with intrinsic brainstem masses and in providing a rapid and safe method for evacuation of the contents of cystic masses.

Thirty two poor grade patients (grade 3, 20 patients and grade 4, 12 patients) with tuberculous meningitis and hydrocephalus were prospectively studied to evaluate the response to external ventricular drainage in predicting outcome after shunt surgery. All grade 3 patients underwent a shunt procedure irrespective of their response to external ventricular drainage, and an attempt was made to correlate the immediate response to external ventricular drainage to their long term outcome. Patients in grade 4 underwent shunt surgery only if there was clinical improvement by at least one grade after external ventricular drainage. Follow up (mean 23.1 months) was available for 30 patients (93%). Of the 20 patients in grade 3, seven underwent shunt surgery directly, 13 after an external ventricular drainage. In the group which underwent drainage, the immediate clinical response was improvement in six, no change in six, and death in one. Long term improvement or death occurred almost equally in all the subgroups. The immediate response to external ventricular drainage was not predictive of the long term outcome in grade 3 patients. All 12 patients in grade 4 underwent an external ventricular drainage and only one improved. The rest continued to deteriorate and succumbed to the disease. Grade at admission was the single most important predictor of good outcome (p=0.002) and severity of hydrocephalus had an adverse impact on outcome (p= 0.04). The rest of the variables studied (age, duration of illness, duration of altered sensorium, CSF cell count, and CSF protein concentrations) had no eVect on long term outcome. All patients in grade 3 should be given the benefit of shunt surgery without a trial of external ventricular drainage. However, patients in grade 4 should undergo an external ventricular drainage in view of the high mortality in this group.

The main objective of our study was to evolve a practical management protocol for neurosurgical patients with hyponatremia and natriuresis, based on their blood volume status and hematocrit. Twenty-one patients with hyponatremia and natriuresis and 3 control patients were studied. Patients with hyponatremia were categorized on the basis of their hematocrit, central venous pressure, and total blood volume. Group A consisted of patients with hypovolemia and anemia (16 patients); Group B patients had hypovolemia but no anemia (5 patients); Group C included those with hypervolemia (0 patients). Patients in Groups A and B received isotonic saline (> 50 ml/kg/d) and oral salt (12 g/d). Additionally, those in Group A were transfused with 500 ml of whole blood. The end points in the study were 72 hours after entry or two consecutive serum sodium values of > 130 mEq/L, whichever was earlier. Hyponatremia was corrected in all the patients within 72 hours (1 patient, < 24 h; 13 patients, < 48 h; and 7 patients, < 72 h). We conclude that most neurosurgical patients with hyponatremia and natriuresis have hypovolemia, with or without anemia. Fluid and salt replacement and a blood transfusion rather than fluid restriction often results in the correction of the hyponatremia. Our findings offer indirect evidence to support the hypothesis that in most of these patients, hyponatremia is caused by cerebral salt wasting syndrome, rather than the syndrome of inappropriate secretion of antidiuretic hormone.