Computed tomography interobserver agreement in the assessment of aneurysmal subarachnoid hemorrhage and predictors for clinical outcome.

BACKGROUND: The severity of aneurysmal subarachnoid hemorrhage (SAH) is often assessed by the clinical state of the patient on presentation, but radiological evaluation of the extent of hemorrhage has rarely been examined in the literature. Several CT scan based grading systems exist yet only a few studies have investigated interobserver agreement. We evaluated five radiological grading systems and assessed their clinical value for early prognostication. METHODOLOGY: This was a retrospective study of patients diagnosed with aneurysmal SAH with a CT scan performed within 72 hours of symptom onset. Four independent observers, blinded to patient outcome, evaluated each scan using the five grading systems. A separate assessor determined 6 month outcome from clinical records. The primary outcome was interobserver agreement for each grading system using the Fleiss κ statistic. The secondary endpoint was the 6 month modified Rankin Scale score, with poor outcome defined as a score of 4-6. RESULTS: 165 patients with a mean age of 59 years were assessed. Interobserver agreement for the Fisher, modified Fisher, Claassen, Barrow Neurological Institute, and Hijdra grading systems were as follows: k=0.53 (moderate), k=0.42 (moderate), k=0.38 (mild), k=0.20 (poor), and k=0.66 (good), respectively. The only independent clinical risk factor for poor outcome was a World Federation of Neurological Surgeons (WFNS) grade of 4 or 5 (adjusted OR 6.55; p<0.05). After adjusting for confounders, Fisher grade 4 (adjusted OR 17.84), modified Fisher grade 4 (adjusted OR 5.65), and Hijdra grade 3 (adjusted OR 3.34) were associated with poor outcome. Receiver operator characteristic analysis revealed that the Hijdra grading system (area under the curve=0.76) was more predictive of outcome compared with the Fisher and modified Fisher systems. A Hijdra cut-off score of 22 was associated with poor outcome (adjusted OR 5.92). CONCLUSIONS: The Hijdra grading system had the best interobserver agreement and was a better independent early predictor for 6 month clinical outcome than the other systems. A Hijdra score ≥22 was associated with poor outcome.

Use of the pipeline embolization device to treat recently ruptured dissecting cerebral aneurysms.

The Pipeline embolization device (PED) is one of the flow-diverting stents approved for the treatment of unruptured large or wide-necked cerebral aneurysms in 2011(1). Its use has now been extended to the treatment of recently ruptured dissecting cerebral aneurysm, carotid pseudoaneurysm from radiation injury, and blister aneurysms(2,3). We aimed to evaluate the effectiveness of utilizing the PED as a primary treatment for ruptured dissecting intracranial aneurysms. A single center retrospective review was conducted for all patients primarily treated with PED for acute subarachnoid hemorrhage (SAH) from ruptured dissecting cerebral aneurysms between December 2010 and February 2013. Patients were followed up with CT angiogram (CTA) or digital subtraction angiogram (DSA). Eight patients with a total of eight dissecting aneurysms were identified. The mean duration from SAH to treatment was 2.5 days. Six of the aneurysms arose from vertebral arteries and two from the basilar artery. Immediate check-DSA confirmed satisfactory contrast stasis in all eight cases, and complete aneurysmal obliteration was achieved at six months. There were two (25%) procedure-related complications, but no major procedure-related complications, such as thromboembolic events or rebleeding from aneurysm were encountered. The PED is a feasible treatment option for ruptured dissecting cerebral aneurysms in acute phase. According to our experience, using PED as flow-diverters in acute SAH does not significantly increase the complication risks or mortality rate if the antiplatelet regime is carefully monitored. Future studies shall evaluate the optimal antiplatelet regimen for using the PED in the acute phase.