AIMS: The purpose of this study is to clarify the rearrangement of the arachnoid membrane on the vestibular schwannoma during its growth in relation to adjacent neurovascular structures for a better understanding of dissecting plane of arachnoid during surgery. METHODS: Arachnoid membrane over the tumour was investigated during surgery with suboccipital transmeatal approach in twenty-six tumours. All microsurgical procedures were recorded with a video and reviewed. The tumour growth was classified into five stages depending upon the tumour diameter in the cerebello-pontine (CP) angle: Stage 1; purely intracanalicular (2 cases), Stage 2; less than 5 mm (2 cases), Stage 3; > or = 5 and <15 mm (8 cases), Stage 4; > or = 15 and <25 mm (9 cases) and Stage 5; > or = 25 mm (5 cases). Rearrangement of the arachnoid on the tumour was conceptualised throughout all stages. RESULTS: All tumours of Stage 1 and 2 were entirely located in the subarachnoid space of the cerebello-pontine cistern without arachnoidal rearrangement, while all tumours of Stages 3 to 5 were enveloped, in the CP angle, with invaginated arachnoid membrane consisting of cerebello-pontine cistern except two surfaces; the medial pole and the tumour surface under the facial and cochlear nerves near the porus. CONCLUSION: The tumour originates subarachnoidally within the internal auditory meatus (IAM) and grows epiarachnoidally in the CP angle. Rearrangement of the arachnoid begins with its adhesion on the medial pole of the tumour along the porus, resulting in the arachnoidal invagination into the cerebello-pontine cistern with further growing of the tumour.

BACKGROUND: Controversial results have been obtained in measuring insulin sensitivity (S(I)) during recombinant human growth hormone (rhGH) treatment in adult growth hormone deficient (GH-deficient) patients. AIMS: The aim of our study was to estimate S(I) before and during treatment using three different methods for quantifying insulin sensitivity in GH-deficient adults treated with rhGH. SETTINGS AND DESIGN: Twenty-one GH-deficient adults were treated with rhGH during 12 months. S(I) was estimated using Minimal model analysis, Homeostatic Model of Assessment (HOMA) and Quantitative Insulin Sensitivity Check Index (QUICKI) before and after 3, 6, 9 and 12 months of rhGH therapy. MATERIAL AND METHODS: Oral Glucose Tolerance Test (OGTT) and Frequently Sampled Intravenous Glucose Tolerance Test (FSIGT) were performed in each patient at respective time intervals. QUICKI and HOMA were calculated using basal values of glucose and insulin from FSIGT. Minimal model computer analysis was calculated from glucose and insulin data obtained during FSIGT. STATISTICAL ANALYSIS: Area under the curve for glucose, insulin and C-peptide were calculated using trapezoidal rule from OGTT data. Differences and correlations were tested using ANOVA for repeated measures, Wilcoxon's matched-paired test, paired t-test, Pearson's correlation and Bland Altman plot. RESULTS: There were no significant changes in S(I) using Minimal model analysis and QUICKI during rhGH treatment. On the contrary, HOMA analysis indicated significant deterioration in S(I) after 12 months of therapy. CONCLUSION: Our study did not demonstrate any changes in S(I) using Minimal model and QUICKI analysis, while there was significant increase in insulin resistance using HOMA model. We suggest that the choice of method for the determination of S(I) may influence the interpretation of results concerning the effect of rhGH therapy on S(I) in GH-deficient adults.

BACKGROUND: The insertion/deletion (I/D) polymorphism of angiotensin converting enzyme (ACE) gene has been associated with progression of renal diseases. AIMS: We investigated its role in the rate of progression of focal segmental glomerulosclerosis (FSGS). METHODS: Forty-seven patients with end-stage renal disease (ESRD) due to FSGS were evaluated. RESULTS: The distribution of ACE genotype was II-25.5%, ID-55.5%, and DD-19%, as compared to 40 controls with genotype of 7.5%, 60%, and 32.5%, respectively (p= NS). In African Americans (AA) the gene frequencies among patients and controls were I-43%, D-57% vs I-36%, D-64%, respectively. This was different than the gene frequencies in White/Hispanic (W/H) patients I-61.5%, D-38.5% vs I-38.6%, D-61.4%, in controls (P < 0.05). In 22 patients with rapid progression (RP) of FSGS to ESRD the genotype distribution was II-18%, ID -64%, and DD-18%. In 25 patients with FSGS who progressed slowly (SP) the genotype was similar (II-32%, ID-48% and DD-20%, P >0.05). With respect to rate of progression, D allele frequency was similar in AA patients (RP 64% vs SP 50%) and W/H patients (RP 36% vs SP 40%). CONCLUSION: Our study reveals no association between the I/D polymorphism of the ACE gene and the presence of and rapidity progression of FSGS.

AIM: To evaluate the accuracy of magnetic resonance (MR) arthrographic imaging in the diagnosis of glenoid labral and ligament tears in recurrent shoulder instability. SETTINGS AND DESIGN: Prospective, comparative study at a tertiary care centre. MATERIAL AND METHODS: Patients with three or more episodes of anterior shoulder dislocation were enrolled in the study. They were subjected to magnetic resonance arthrography (MRA) for delineation of abnormalities. The findings obtained at MRA were compared with those found at arthroscopy and surgical exploration. RESULTS: MRA detected glenoid tears in all 22 patients with 20 (90%) patients having antero-inferior tears, 3 (14%) patients had superior labral involvement and 2 (10%) patients had posterior labral abnormality. On arthroscopy, antero-inferior, superior and posterior labral tear were found in 21 (95%), 5 (22%) and 7 (32%) patients respectively. MRA showed a sensitivity of 95%, and a specificity of 100% for the detection of the antero-inferior labral tears. The sensitivity of MRA for the detection of superior, middle and inferior glenohumeral ligament tear was 83%, 80% and 86% with a specificity of 100%, 71% and 93% respectively. MRA was 100% sensitive for the detection of rotator cuff injuries and detection of bony lesions like Hill-Sach's and bony Bankart's lesion. CONCLUSIONS: MRA is a sensitive and specific modality for evaluation of anterior shoulder instability.

BACKGROUND AND AIMS: Snake bite is an important cause of mortality and morbidity in certain parts of Sri Lanka. This study was designed to determine the offending snakes, neurological manifestations, disease course, and outcome in neurotoxic envenomation. METHODS AND MATERIAL: Fifty six consecutive patients admitted with neurological manifestations following snake bite were studied prospectively. Data were obtained regarding the offending snakes, neurological symptoms, time taken for onset of symptoms, neurological signs, and time taken for recovery. RESULTS: The offending snake was Russell's viper in 27(48.2%), common and Sri Lankan krait in 19(33.9%), cobra in 3(5.4%), and unidentified in 7(12.5%). Ptosis was the commonest neurological manifestation seen in 48(85.7%) followed by ophthalmoplegia (75%), limb weakness (26.8%), respiratory failure (17.9%), palatal weakness (10.7%), neck muscle weakness (7.1%), and delayed sensory neuropathy (1.8%). Neurological symptoms were experienced usually within 6 hours after the bite. Following administration of antivenom, the signs of recovery became evident within a few hours to several days. The duration for complete recovery ranged from four hours to two weeks. CONCLUSIONS: Complete recovery of neuromuscular weakness was observed in all patients except for one who died with intracerebral haemorrhage shortly after admission.

BACKGROUND: Several studies in the last few years have shown that the standard 250 micro g dose used in ACTH stimulation test may be very high and have suggested that a dose of 1 micro g may be sufficient for evaluating hypothalamo-pituitary adrenal (HPA) axis. AIMS: To evaluate the role of low dose ACTH stimulation test in patients with suspected Secondary Adrenal Insufficiency (SAI). SUBJECTS AND METHODS: Thirty-one patients of suspected SAI with a documented pituitary lesion and seven normal healthy controls were included in the study. All the subjects underwent ACTH stimulation test with standard high dose (HD= 250 microg) and low dose (LD= 1 microg) ACTH. Insulin Induced Hypoglycaemia (IIH) test was done in 7 out of 9 patients in whom the results of the two tests were discordant. The cut off for normal HD stimulation test was taken as peak cortisol response > 18 microg/dl and for LD test, either a cortisol response of > 18 microg/dl or an increment of more than 7 micro g/dl over the basal value at any time during the test, on the basis of response observed in controls. RESULTS: 22/31 patients (74%) in SAI group showed concordant results with both tests, whereas nine patients had discordant results. These nine patients showed AI with LD ACTH, but HD ACTH test showed a normal response. In 7 of these 9 patients who underwent IIH, AI was confirmed in 6. CONCLUSION: The LD ACTH stimulation test seems to be better than HD ACTH stimulation test for evaluating HPA axis in patients with suspected SAI. When basal cortisol is normal, LD ACTH stimulation test detects subtle SAI.

We describe a patient with orofacial pain as the presenting symptom caused by a mandibular metastasis from a previously undiagnosed cancer of the prostate. This possibility should be considered in the differential diagnosis of male patients presenting with orofacial pain.

Chordomas are rare tumours which arise from remnants of the primitive notochord. They occur primarily in the sacrum, clivus and cervical regions. We report a case of retroclival chordoma which presented as an extradural haemorrhage following minor trauma. The underlying tumour was not apparent on imaging performed immediately following the event, and chordoma presenting in this manner has not previously been described in the literature. The tumour became apparent on subsequent imaging, and progressed despite surgical debulking and radiotherapy.

Gastroepiploic aneurysms are extremely rare. They occur mainly in elderly men and in 90% of cases are ruptured at presentation. Visceral aneurysms though rare should be borne in mind in cases of unexplained haemorrhagic shock. We present a case of a 79-year-old man who presented with abdominal pain, hypotension and anaemia but no obvious source of bleeding. He had undergone a prior aorto-bifemoral graft. The patient refused an operation and died the following day.

Electro Convulsive Therapy (ECT) in pre-pubertal children is a controversial and underreported treatment. Even though the effectiveness and side effects of ECT in adolescents are comparable with those in adults, there is a pervasive reluctance to use ECT in children and adolescents. We report the case of a pre-pubertal child in an episode of severe depression with catatonic features, where a protracted course of ECT proved life-saving in spite of prolonged duration of seizures and delayed response to treatment. The case illustrates the safety and efficacy of ECT in children. Relevant literature is also reviewed along with the case report.

Anxiety disorders and medical illness present to the primary care physician as a common comorbidity. This article aims to review the literature on the prevalence of anxiety disorders in patients presenting to primary care physicians; to address the key issues in assessing the comorbid condition; and to discuss psychological and pharmacological treatment options for patients with a comorbid anxiety disorder and medical illness. Anxiety disorders are highly prevalent within the primary care population, and these disorders significantly impact the patient's course and outcome. Fortunately, primary care physicians have a variety of effective cognitive, behavioral and pharmacological interventions available for managing these patients with comorbid anxiety and medical illnesses.

Cancer survival estimation is an important part of assessing the overall strength of cancer care in a region. Generally, the death of a patient is taken as the end point in estimation of overall survival. When calculating the overall survival, the cause of death is not taken into account. With increasing demand for better survival of cancer patients it is important for clinicians and researchers to know about survival statistics due to disease of interest, i.e. net survival. It is also important to choose the best method for estimating net survival. Increase in the use of computer programmes has made it possible to carry out statistical analysis without guidance from a bio-statistician. This is of prime importance in third- world countries as there are a few trained bio-statisticians to guide clinicians and researchers. The present communication describes current methods used to estimate net survival such as cause-specific survival and relative survival. The limitation of estimation of cause-specific survival particularly in India and the usefulness of relative survival are discussed. The various sources for estimating cancer survival are also discussed. As survival-estimates are to be projected on to the population at large, it becomes important to measure the variation of the estimates, and thus confidence intervals are used. Rothman's confidence interval gives the most satisfactory result for survival estimate.