gms | German Medical Science

Objective: This study was conducted to determine the risk factors in the treatment of symptomatic and asymptomatic unruptured intracranial aneurysms (UIAs) with special regard on the clinical impact of intraprocedural aneurysm rupture (IAR) and periprocedural ischemia.

Method: A single center retrospective data analysis of 563 UIAs treated between 2000 and 2010 was conducted - 363 microsurgical and 200 endovascular procedures. Treatment assignment was made on the basis of individual aneurysmal criteria in an interdisciplinary neurovascular conference.

Results: Prevalence of aneurysms’ diameter was: < 7 mm (195;35 %), 7 - 15 mm (303;54 %), 16-24mm (40;7%) and <FONT face=Symbol>³ </FONT>25 mm (25;4 %). 92 aneurysms were classified as symptomatic - cranial nerve palsies (34), transient ischemic attacks (40) and brain stem compression (18) - 12 % and 23.5 % in the microsurgical and endovascular group (p = 0.001). Symptomatic aneurysms exhibited significantly larger diameters compared to asymptomatic ones (p = 0.001). Overall rate of transient, permanent morbidity and mortality in microsurgery was 14 %, 4.9 % and 0 % and 12 %, 6 % and 2 % in endovascular treatment. Risk factors for overall morbidity and mortality were IAR, periprocedural ischemia, age, aneurysm diameter > 7 mm, aneurysms in the posterior circulation and smoking in both treatment modalities. Furthermore, morbidity was significantly increased in endovascular treatment of symptomatic aneurysms (p = 0.001) – mainly in aneurysms symptomatic of brain stem compression. IAR occurred in 34 (9.4 %) microsurgical and 8 (4 %) endovascular procedures (p = 0.03) and was associated with significantly worse short-term outcome after microsurgical and short- and long-term outcome after endovascular procedures and followed by fatal outcome in 4 endovascular cases. Risk factors for IAR were age, aneurysm diameter > 7 mm, symptomatic aneurysms, hypertension and smoking in microsurgery. Periprocedural ischemia (12 % vs. 9 %) resulted in significantly worse short- and long-term outcome in both groups. Respective risk factors for ischemia were IAR during microsurgery, diameter > 7 mm and symptomatic aneurysms in either group.

Conclusions: Symptomatic UIAs bear a significantly larger procedural risk. IAR was less frequent during coiling but was associated with relevant mortality. IAR and periprocedural ischemia represent significant treatment associated risks, which should be taken into account in interdisciplinary treatment planning and patients' counseling, especially in symptomatic aneurysms.