Computerized Angiographic Occlusion Rating for Ruptured Clipped Aneurysms is Superior to Subjective Occlusion Rating

BACKGROUND AND PURPOSE

The computerized occlusion rating to estimate angiographic occlusion of embolized aneurysms is superior to the subjective occlusion rating. In this study, we compared the 2 methods in the analysis of aneurysms clipped after subarachnoid hemorrhage.

MATERIALS AND METHODS

The pre- and postoperative angiographic images (DSA) of 95 selected patients were analyzed and stratified in 4 grades (grade 0 for 100%, grade I for <99%-90%, grade II for <89%-70%, grade III for <70% occlusion) by using the subjective (angiographic) occlusion rating and the computerized (angiographic) occlusion rating. For the subjective occlusion rating, the occlusion rate was estimated; for the computerized occlusion rating, the "occluded" and "nonoccluded" aneurysm areas were automatically calculated in square millimeters after outlining the ideal occlusion line.

RESULTS

With the subjective occlusion rating, 75 (78.9%), 12 (12.6%), 7 (7.4%), and 1 (1.1%) and with the computerized occlusion rating 45 (47.4%), 24 (25.3%), 20 (21.0%), and 6 (6.3%) patients had aneurysms stratified to grades 0, I, II and III, respectively. The interobserver variation was significant with the subjective occlusion rating but not with the computerized occlusion rating. The subjective occlusion rating overestimated aneurysm occlusion in 30 (31.6%) patients. Mean values were the following: subjective occlusion rating of 97.5 ± 6.3% and computerized occlusion rating of 93.5 ± 9.7%; P = < .001. No patient rebled, and 4 patients underwent retreatment during 36 ± 38.9 months; the predictive value (log-rank, Kaplan-Meier) of the subjective and computerized occlusion ratings with respect to retreatment was highly significant for both methods (subjective occlusion rating: χ(2), 29.65; P < .001; computerized occlusion rating: χ(2), 35.57, P < .001).

CONCLUSIONS

The 2 methods showed remarkable differences in the estimation of the angiographic occlusion rates of clipped aneurysms. The clearly lower interobserver variation of the computerized versus subjective occlusion rating may indicate a superiority of the computerized occlusion rating.

The pharyngo-tympano-stapedial variant of the middle meningeal artery. A case report

Atypical origin of the middle meningeal artery from the cervical internal carotid artery is a rare angiographic finding. We describe a case of the pharyngo-tympano-stapedial variant of the middle meningeal artery in a young patient. In this vascular variation the proximal segment of the middle meningeal artery, corresponding to an annexed inferior tympanic artery, originates from the cervical carotid artery. Then over the promontory it unites with the superior tympanic artery and continues with its intracranial course via the petrous branch.

Endovascular occlusion of a lacerated primitive trigeminal artery during surgical resection of clival chordoma. a case report

We describe a case of a persistent primitive trigeminal artery (PPTA) coexistent with a clival chordoma. During surgery of the tumor, the partially incorporated PPTA was inadvertently traumatized and ruptured. The operation was discontinued and the PPTA was endovascularly occluded permitting further safe resection of the tumor.

Visual worsening after incomplete coiling of a small asymptomatic aneurysm: case report and review of the literature

OBJECTIVE

Complications with increased mass effect on surrounding structures have as yet only been noted after coiling of large, giant, and thrombosed aneurysms. We describe a case of optic chiasm compression after incomplete coil embolization of a small ICA aneurysm and discuss the potential mechanisms causing this phenomenon.

CASE REPORT

A 57-year-old male presented with an incidental, 7-mm diameter, C2 segment, ICA aneurysm. Endovascular intervention with platinum coils resulted in 80% obliteration. Approximately three weeks later the patient developed visual changes which progressed over 10 days to a homonymous hemianopsia with a central scotoma. A pterional craniotomy was performed to decompress and to definitively clip the aneurysm. Histological evaluation of the aneurysm showed sinusoidal vessels, filled with proliferated endothelial cells and being encapsulated by fibrous tissue, suspicious for exposure to systemic blood pressure.

CONCLUSION

Even small aneurysms undergoing incomplete coil embolization may affect surrounding, eloquent neural structures due to unexpected tissue formation in the aneurysm.

The Accuracy of Plain Skull X-ray Examination as a Predictor of Recanalization Following Guglielmi Detachable Coil Embolisation in the Treatment of Cerebral Aneurysms

SUMMARY

We evaluated the accuracy of plain skull x-ray series as an imaging modality for the follow-up of cerebral aneurysm recanalization after Guglielmi Detachable Coil (GDC) embolisation. We retrospectively reviewed of 100 consecutive follow-up angiograms and skull x-ray examinations in 78 patients harboring 82 aneurysms and in whom 85 procedures were performed. Angiography was performed between 1 and 54 months (mean: 10.8 months) after embolisation. The skull series (AP, lateral and Towne's projections) were taken at the time of follow-up angiography. Each follow-up angiogram and skull series were compared to the immediate post-coiling, correlating presence or absence of coil compaction on the skull series and recanalization of the aneurysm at angiography. In 97 (97%) examinations, skull x-ray findings correlated with the angiographic findings. In three cases, skull x-ray examination suggested compaction when no recanalization was seen angiographically; in these three cases, the aneurysms were small and found to be more thrombosed than baseline. In no case did angiographic recanalization occur in the absence of compaction on skull series. These findings yield 100% sensitivity, 95% specificity, 93% positive predictive value, 100% negative predictive value and 97% accuracy. The location, size, configuration and neck/dome ratio of the aneurysm were not related to the correlation between angiography and skull x-ray exam. Skull x-ray series is a safe, accurate, and costeffective mode of follow-up for patients with GDC-treated aneurysms. The possibility of it replacing angiography still requires a more comparative skull x-ray modality in follow-up studies.