Details of a simple low-resistance flap valve for pulmonary ventilation studies are presented. It has a space of 11 ml, weighs 28 g and is constructed from 3 mm thick perspex sheet. The opening pressure for both the inlet and the outlet is zero as its flaps normally remain open. The resistance of the valve to a flow of air at a rate of 20 l min-1 is 2.2 mm of water at the inlet and 4.2 mm of water at the outlet. At a rate of flow of 100 l min-1 the corresponding figures are 8.9 and 24.6 mm of water. All these values compare favourably with those obtained from three commercially available units. The valve has been in use over the past four years and the patient compliance has been found to be excellent.

BACKGROUND Watertight dural closure is a vital and desirable step following all intracerebral operations to prevent CSF leakage, consequent infection and wound dehiscence and delayed wound healing which in turn increases patient morbidity and mortality. Various autologous and synthetic materials have been tried for duraplasty. This study was done to compare two types of synthetic materials used for duraplasty. METHODS This randomised prospective study was done at our institute on 56 patients who underwent decompressive craniectomy. Patients were randomly divided into two groups, one group underwent duraplasty with synthetic fabric patch graft and the other group underwent duraplasty with collagen matrix graft and results were compared between the two groups. RESULTS Patients who underwent duraplasty with collagen matrix graft were found to have a significantly reduced operating time of nearly 34 minutes as compared to the synthetic fabric patch and also there was no incidence of CSF leakage or wound infection in those patients in whom collagen matrix was used. CONCLUSIONS Collagen matrix graft is far superior to synthetic fabric graft for duraplasty as it saves valuable operating time and has fewer complications as compared to synthetic fabric grafts. KEY WORDS Duraplasty, Collagen Matrix Graft, Synthetic Fabric Patch Graft

BACKGROUND Lumbosacral Radiculopathy is one of the most common disorders treated by neurologists and spine surgeons. Intervertebral disc herniation is the most common cause of lumbosacral radiculopathy in patients under the age of fifty years. There are some known factors which can increase the degeneration of lumbar disc like smoking, sedentary lifestyle, driving, male sex, increasing age, obesity, heredity and poor posture. Acute events can easily produce disc prolapse in an individual already having degenerated disc. A retrospective and prospective study was undertaken among patients of lumbar disc prolapse to measure the acute events that lead to disc prolapse.

BACKGROUNDCervical disc prolapse causing radiculopathy is one of the most common disorders treated by both neurologists and spine surgeons. Herniation of disc most commonly occurs in those below the age of 45 years. Pain appears in the neck and radiates towards the arms or vice versa i.e. arises in the arm and radiates to the neck. With aging and other risk factors, nucleus pulposus of cervical intervertebral disc show degeneration or dehydration. This disc may rupture through the posterior annulus fibrosus into the spinal canal or into the neural foramen compressing the exiting nerve root. Acute events can produce disc prolapse in those susceptible individuals who are already having degenerated disc. METHODSThe study includes patients attending the OPD or those admitted in the Neurology and Neurosurgery Department of Calcutta National Medical College and Hospital with symptoms of cervical radiculopathy. The study period was from 01.03.2018 to 28.02.2019. Inclusion criteria of the study were radicular pain with or without sensory or motor signs with MRI evidence of root compression, electrophysiologic evidence of cervical radiculopathy when MRI was contraindicated or noncontributory and symptoms onset was within the last 3 months. RESULTSIn this retrospective descriptive study, acute events noted within 48 hours that lead to cervical disc herniation are road traffic accidents in 27.9%. of the cases, lifting heavy objects accounted for 16.1% of the cases, violence and assault accounted for 11.7% of the cases, fall accounted for 10.3% of the cases, repetitive strain accounted for 10.3% of cases, Sports & recreation accounted for 7.3% of the cases, falling objects accounted for 4.4% of the cases and no obvious cause (idiopathic) accounted for 11.7% of the cases. 77.9% of the cases of cervical disc prolapse occurred in persons below 49 years of age. In this series, incidence of cervical disc prolapse was higher in males 69.1%. CONCLUSIONSThere is a need for increasing awareness among both the medical and general population about the acute events that can cause cervical disc herniation so that necessary precautions taken and lifestyle modifications be done to maintain cervical spine health.