AbstractsMedical & Health Science

Intracranial aneurysms (IAs) affect 2-3% of the population. In Finland, their rupture rate has been exceptionally high. This study aims to evaluate the prevalence and risk factors affecting neuro-ophthalmic findings in patients undergoing treatment for IAs. We also investigate the utility of conventional head computed tomography (CT) in the diagnosis of Terson´s syndrome (TS, vitreous hemorrhage in association with aneurysmal subarachnoid hemorrhage (aSAH)). Patients treated endovascularly or microsurgically for their IAs at the Department of Neurosurgery, Helsinki University Central Hospital, in 2011 prospectively underwent a neuro-ophthalmic examination preoperatively and at 3 days, 14 days, 2 to 4 months, and 6 months postoperatively. Findings suggestive of TS, as independently reviewed by two radiologists, on conventional CT head scans were compared with dilated fundoscopic findings. Participants comprised 121 patients with a ruptured aneurysm and 142 patients with an unruptured intracranial aneurysm (UIA). TS was present on fundoscopy in 13 patients (11%); the overall observed agreement between the two radiologists was 96% (116/121), with a substantial κ of 0.69 (95% CI 0.56-0.82). On average, CT demonstrated sensitivity of 42% and specificity of 97%. Factors independently predicting TS were female gender (OR 5.34, 95% CI 1.05-27.17) and World Federation of Neurosurgical Societies (WFNS) grade (OR 15.05 for grades IV-V vs. I-III, 95% CI 3.07-73.89). For patients with aSAH, the frequencies of a third, fourth, or sixth nerve palsy were 11 (9%; preoperatively), 16 (13%; immediately postoperatively), and 3 (3%; at the last follow-up), compared with corresponding frequencies of 6 (4%), 15 (11%), and 7 (5%) for patients with UIAs. Significant risk factors for postoperative eye movement disorders (EMDs) among patients with UIAs were aneurysm location in the posterior circulation (OR 142.02, 95% CI 20.13-1002.22) and aneurysm size (OR 1.28, for each 1-mm increase in diameter, 95% CI 1.12-1.47). After a follow-up time of 6 months, patients with aSAH presenting with visual field defects (VFDs) for aneurysm- or operation-related reasons numbered 20 (19%); homonymous VFDs were the most prevalent finding, and in logistic regression analysis, they were significantly associated with the Hunt and Hess (H and H) grade (OR 4.45 for grades IV-V vs. I-III, 95% CI 1.21-16.39) and presence of intracranial hemorrhage (OR 8.93, 95% CI 2.14-37.28). By contrast, seven patients (5%) treated for a UIA had VFDs. Poor-grade aSAH (H and H or WFNS grade IV-V) appears to be a strong predictive factor for TS and VFDs. With a high specificity value, conventional head CT scan might prove a useful tool in the diagnosis of TS. Although a common finding in the acute postoperative stage of ruptured and unruptured IAs, EMDs show marked improvement during follow-up. Väitöstutkimuksessa selvitettiin aivovaltimopullistumien (aneurysmien) ja niiden hoidon aiheuttamia silmälöydöksiä, joihin kuuluvat näöntarkkuuden aleneminen, silmänliikehäiriöt…