Preliminary experience of carbon fibre cage prostheses for treatment of cervical spine disorders.

The objective of this study was to assess the technical feasibility, and the clinical and radiological results of interbody fusion with a carbon fibre cage following anterior cervical discectomy. Nineteen consecutive patients, eight male and 11 female, with an age range from 28 to 75 years (mean 45) underwent anterior cervical discectomy and interbody fusion with a carbon fibre cage at one or two levels. Subjective assessment of symptomatic improvement and radiological assessment of cervical spine alignment and stability was made. All complications were recorded. The procedure was technically feasible. There was no increased morbidity and the length of procedure was no longer when compared with the similar operation but using tricorticate bone graft. All patients initially lost their radicular symptoms and the patients with myelopathy had subjective improvements of their symptoms. Fourteen of the 17 patients with neck pain showed some improvement. Bony fusion was achieved in all cases.

Phosphorus-31 magnetic resonance spectra reveal prolonged intracellular acidosis in the brain following subarachnoid hemorrhage.

Subarachnoid hemorrhage may be complicated by cerebral ischemia which, though reversible initially, can progress to an irreversible neurological deficit. 31P magnetic resonance spectroscopy, which can determine intracellular pH and thus detect areas of ischemia noninvasively, was applied to 10 patients on 30 occasions, at various times after subarachnoid hemorrhage. In 5 of them, there were focal areas of the brain in which the intracellular pH was reduced to < 6.8 compared with the normal range of 7.05 +/- 0.05. Consciousness was impaired in 4 of these patients. Repeat studies in these 4 patients showed that intracellular pH remained abnormally low for several days but eventually returned toward normal. The return of intracellular pH to normal paralleled an improvement in clinical condition in each case. In the fifth patient with lowered regions of intracellular pH, there had been an impaired level of consciousness and a transient focal deficit prior to the single study. In the other 5 patients there were no areas of reduced pHi even though in 3 of them there was intraventricular or cisternal blood shown on brain computerized tomography. In 2 of these 3 patients there were no abnormal neurological signs at the time of the magnetic resonance study. The third patient had a dense and persistent hemiparesis. The remaining two patients had no abnormal neurological signs at any stage. We suggest that the areas of acidosis may reflect ischemia which is potentially reversible. Since the technique is noninvasive, sequential 31P magnetic resonance spectroscopy of the brain offers a method of detecting cerebral ischemia and, more importantly, of assessing methods of treatment.