✓ The oncotic pressure of fluid from subdural heatomas and subdural hygromas was compared to that of simultaneously drawn venous blood in 20 patients. There was no significant difference in the oncotic pressure of fluid from subdural hematomas and venous blood; however, the oncotic pressure of fluid from subdural hygromas was significantly less than that of blood. This finding fails to support the Zollinger and Gross modification of Gardner's theory, that chronic subdural hematomas grow and produce symptoms after a latent interval because they attract fluid from the blood via dural vessels.
Object. In this article, pathological, radiological, and clinical information regarding unruptured intracranial aneurysms is reviewed.
Methods. Treatment decisions require that surgeons and interventionists take into account information obtained in pathological, radiological, and clinical studies of unruptured aneurysms. The author has performed a detailed review of the literature and has compared, contrasted, and summarized his findings. Unruptured aneurysms may be classified as truly incidental, part of a multiple aneurysm constellation, or symptomatic by virtue of their mass, irritative, or embolic effects. Unruptured aneurysms with clinical pathological profiles resembling those of ruptured lesions should be considered for treatment at a smaller size than unruptured lesions with profiles typical of intact aneurysms, as has been determined at autopsy in patients who have died of other causes. The track record of the surgeon or interventionist and the institution in which treatment is to be performed should be considered while debating treatment options. In cases in which treatment is not performed immediately, ongoing periodic radiological assessment may be wise. Radiological investigations to detect unruptured aneurysms in asymptomatic patients should be restricted to high-prevalence groups such as adults with a strong family history of aneurysms or patients with autosomal dominant polycystic kidney disease. All patients with intact lesions should be strongly advised to discontinue cigarette smoking if they are addicted.
Conclusions. The current state of knowledge about unruptured aneurysms does not support the use of the largest diameter of the lesion as the sole criterion on which to base treatment decisions, although it is of undoubted importance.
Report of two cases
✓ Two cases with technical failures of aneurysm clipping are reported in which immediate postoperative angiography permitted corrections to be made, with good outcome.
Bryce K. Weir
✓ A retrospective clinico-pathological analysis of 78 cases of fatal subarachnoid hemorrhage (SAH) was carried out: 71% had a pathological diagnosis of pulmonary edema (PE), and of these 31% had a clinical diagnosis of PE. Patients with pathological PE were younger and died sooner after their SAH than those without. The incidence of PE fell with the passage of time following SAH, while the occurrence of pneumonia and embolism increased. There were hypoxemia and hypocapnia in both groups, more severe in the group that had pathological PE. The pathophysiology of neurogenic PE is discussed and possible therapeutic approaches indicated.
Bryce K. A. Weir
✓ A prospective study of 100 patients undergoing discectomy was carried out. The neurological findings were documented preoperatively and at 1 month and 1 year postoperatively. The clinical and radiological data were analyzed with respect to significant associations. There were no complications. At a minimum of 1 year postoperatively, 63% of patients had complete relief of back pain and 73% had complete relief of leg pain. A discriminant analysis equation was derived which assessed the relative significance of factors as determinants of outcome. A method is given for estimating whether a patient will have a good or a poor outcome following the discectomy. Factors shown to be of significance should be recorded in prospective series to allow for comparison as to the efficacy of different methods of treatment. The results are better than those described for chemonucleolysis.
Bryce Weir and Philip Gordon
✓ Plasminogen, alpha2-antiplasmin, fibrinogen, fibrin degradation products (FDP's), and hemoglobin were measured in the supernatant fluid of 25 chronic subdural hematomas and five chronic subdural hygromas. The 30 patients underwent pre- and postoperative computerized tomography. The hematomas were characterized by low fibrinogen and high fibrin degradation product concentrations. The hemoglobin content varied directly with the alpha2-antiplasmin, and inversely with the plasminogen. Four patients underwent reoperation for recurrences. The initial fluid from these cases was characterized by relatively high plasminogen and low alpha2-antiplasmin. The hygromas had no hemoglobin, and low fibrinogen, high FDP's, low alpha2-antiplasmin, and variable plasminogen levels. It is possible that those cases having the greatest capacity to produce plasmin (high plasminogen and low alpha2-antiplasmin) can produce more FDP's which in turn causes more rebleeding and an increased risk of reaccumulation of chronic subdural hematomas.
An Analysis of 63 Cases
Bryce Weir and Arthur R. Elvidge
Bryce Weir and Keith Aronyk
✓ A retrospective analysis of 224 patients with a ruptured supratentorial aneurysm, admitted to the care of one of six neurosurgeons on the day of or the day following their subarachnoid hemorrhage, was carried out. Both postoperative and management mortality rates were calculated by the grade of the patient on admission. There were no statistically significant differences in postoperative and management mortality rates when patients were categorized by time of operation, except for the increased management mortality for Grade 3 and 4 patients who were operated on late.