A patient with delayed onset of deteriorating consciousness and episodes of opisthotonos, following rupture of an aneurysm of the basilar artery is described. The condition was reversed by intravenous nimodipine and the final outcome was excellent.
Computed tomographic (CT), magnetic resonance (MR), MR angiographic and angiographic images, obtained after complete nidus obliteration had been angiographically confirmed, were reviewed in 9 patients who had undergone Gamma Knife treatment for cerebral arteriovenous malformations (AVMs). The period between angiographic confirmation of nidus obliteration and the most recent examinations was 12–84 months (mean 29 months). The patients ranged in age from 9 to 54 years (mean 22 years). There were 6 females and 3 males. In 8 patients, the obliterated nidus was shown on CT to be isodense. Calcification was identified in 3 patients, 1 of whom had not shown calcification on CT before treatment. Contrast enhancement of the nidus was seen in 6 patients, in 5 of whom a significant time-related decrease in contrast enhancement was observed following nidus obliteration. In 6 patients, T1-weighted MR imaging showed a hypointense nidus in 4 cases, both hypo- and isointense in 1 and isointense in 1. T2-weighted imaging showed a more varied nidus intensity than was seen on T1-weighted imaging. No flow signal void was demonstrated in any of these cases. After gadolinium administration, the nidus was enhanced in all cases, markedly in 4 and moderately in 2. In 5 of the 6 cases a time-related decrease in gadolinium enhancement was observed following nidus obliteration. This change was, however, less significant than that observed on contrast-enhanced CT. Angiography and/or MR angiography showed no vascular abnormalities in 7 patients. These results show that radiosurgery-induced changes in a nidus may continue for several years after angiography has shown complete AVM obliteration. These late changes can be considered to involve further obliteration of the remaining or recanalizing vessels, reflecting an ongoing process from coagulation necrosis to liquefaction necrosis.
EDITOR-It would appear from the article by Krilov et al.[1], on antibody-mediated enhancement of respiratory syncytial virus (RSV) infection that the authors, and presumably the referees of the Journal, were unaware of an earlier publication from my colleagues and me [2] in this area.We demonstrated that human sera containing RSV-specific antibodies enhanced the in vitro infection
EDITOR—Brada and Cruickshank express their concerns about the lack of evidence based research in the field of radiosurgery.1 We agree that radiosurgery replaced neurosurgical resection or fractionated radiotherapy in the treatment of certain intracranial lesions before randomised controlled trials were performed.2–5 However, the original and continual biological basis for radiosurgery remains strong. …
