Moe Khan

Acute spinal cord injury in the rat: comparison of three experimental techniques

Three techniques to produce experimental spinal cord injuries in the rat are compared; 1) the weight dropping method, 2) the aneurysm clip compression method and 3) the extradural balloon compression method. In principle, different forces were used in technique one, while a constant force for different durations is maintained in techniques two and three. The relationship between these different types of injuries and subsequent clinical recovery was assessed quantitatively by the inclined plane method of Rivlin and Tator. The weight dropping technique was found unreliable for experimental spinal cord injury in the rat while the aneurysm clip compression technique resulted in consistent cord injuries with respect to subsequent clinical recovery. The extradural balloon compression method invariably resulted in complete recovery after three and five minutes but no recovery after seven minutes of 0.1 cc air inflated balloon compression of the cord indicating a steep dose--response curve. However, using a 0.2 cc air inflated balloon, no recovery was noted after one minute compression. The major factor in the pathogenesis of spinal cord injury produced by the weight dropping technique is believed to be mechanical, while both mechanical and vascular factors seem to operate in the clip and balloon compression techniques.

CSF shunt complications: an analysis of contributory factors

The complications arising from 195 shunting procedures are described and correlated with patient and operative variables. Neither the patients age, sex, type of hydrocephalus, length of surgery, nor the use of prophylactic antibiotics correlated significantly with subsequent shunt complications. However, the surgeon performing the procedure and the type of shunt used were highly significant correlates.

Hemorrhagic changes in experimental spinal cord injury models

Early hemorrhagic changes in the spinal cord were compared in three experimental spinal cord injury models in the rat in order to determine the nature and consistency of spinal cord hemorrhage following specific and quantitated forces of injury. The spinal cords were injured by weight-dropping, aneurysm clip and extradural balloon compression techniques. Hemorrhagic changes were assessed quantitatively by the image analyser at 1 and 3 hours after injury. Tissue damage was assessed by determining the percentage of total cross sectional area containing hemorrhage. The extent of hemorrhage at site of injury in the clip and balloon preparations was equal, but several times lower in the weight-drop induced injury. Within each experimental group no appreciable differences were observed at the site of injury between the 1 and 3 hours preparations. The variability of damage within experimental groups was most in the weight-dropping and balloon and least in the clip preparations. Differences were also indicated with respect to the distribution of hemorrhage in grey versus white matter. These findings may be of significance when functional recovery is considered in various experimental acute spinal cord injury models.

Clinical - radiological correlates in intracerebral hematomas due to aneurysmal rupture.

In this series of intracerebral hematomas from aneurysmal rupture, gathered from several neurosurgical services, certain morphological features were studied in detail. Patients with very large hematomas tended to have poor neurological grades on admission to hospital and their immediate discharge outlook was correspondingly poor. Ruptured middle cerebral and pericallosal artery aneurysms were relatively common causes of intracerebral hematomas. Patients with temporal lobe hematoma did relatively well; those with parietal hematoma did poorly. The larger the hematoma the less chance there was of developing cerebral vasospasm but the more likely was pre-operative brain herniation. The survival was more closely linked to size and location of the hematoma than to the location of aneurysm or the degree of midline shift.

Pasteurella Multocida Subdural Empyema: A Case Report

The first case of Pasteurella Multocida subdural empyema is reported. This was secondary to hematogenous spread from the pharynx to a chronic subdural hematoma. Positive cultures were obtained from the primary source, the blood and the subdural space. The patient was discharged with no neurological deficit following surgical drainage and parenteral antibiotics. The incidence, predisposing factors, clinical features, bacteriology, diagnostic procedures, treatment and mortality of subdural empyema are briefly discussed.