Neurological, neuropsychological and psychosocial outcome of treatment for unruptured intracranial aneurysms

Abstract

This thesis investigates the outcome of treating unruptured intracranial aneurysms (UIAs). The effects of aneurysm rupture are potentially devastating with estimates that approximately 50% of cases result in death or long term disability. With rupture producing such disastrous consequences it seems sensible to treat these aneurysms before this event occurs. But in considering this option it needs to be noted that most aneurysms never rupture. The primary issue then becomes one of weighing up the risks and benefits of treatment. Whilst a review of thirty five studies published between 1977 and 2002 suggests that outcome from UIA treatment is reasonably good many of the complex issues associated with treatment remain controversial. The current study used a prospective design to evaluate the outcome of UIA treatment. Experimental participants (n=26) were tested prior to treatment, during hospitalisation, at three months, six months and, where relevant, at twelve months following treatment. Of the 26 UIA participants, 16 had experienced a previous aneurysm rupture and 10 had not. The UIA treated groups performance was compared to matched controls (n=20). Psychosocial outcome data were also collected for a group of untreated UIA participants (n=23) and a group of "close others" (n=22). Results indicate neurological morbidity (attributed to a combination of previous aneurysm rupture and current UIA treatment) ranged between 5% (Rankin Scale) and 10% (Glasgow Outcome Scale). Reliability of change analysis revealed a pattern of cognitive deficits in 10% of cases as a result of the UIA treatment. This finding of a moderate UIA treatment effect was, to some extent, supported by further individual data analysis. In addition, 25% of participants changed their work role or did not return to work following treatment, although it is difficult to separate out the effect of previous subarachnoid haemorrhage from this result. Treated UIA participants did not however report psychosocial deficits following treatment, instead frequently describing improvements in quality of life and psychological functioning. In the untreated participants there was a trend towards minor decreases in overall quality of life whilst the "close others" of treated UIA participants also reported a trend towards minor psychological functioning impairments. It was concluded that whilst a small percentage of participants reported a poor outcome following UIA treatment, outcome was better than that which has been observed to follow aneurysm rupture. In addition, a minor cost was also found to be associated with harbouring an untreated UIA and with caring for a patient with a treated UIA.