Validation and initial application of a semiautomatic aneurysm measurement software: a tool for assessing volumetric packing attenuation.
OBJECTIVE
Precise aneurysm measurements and volume embolization ratios are essential for long-term durability of endovascular coil embolization. We evaluated the accuracy of newly developed semiautomatic cerebral aneurysm measurement software, NeuroVision, and explored the value of volume embolization ratio in the prediction of re-treatment.


METHODS
We compared software-derived volume measurements of 4 silicone aneurysm models with those calculated with an approximation formula and ground truth values (validation study). We used NeuroVision to retrospectively evaluate outcomes of 100 unruptured aneurysms (97 patients) treated with embolization (clinical study). Aneurysm size (height, width, and neck), volume, and volume embolization ratios were calculated for 3 groups (stable, recanalization, and re-treatment) and were compared.


RESULTS
This validation study illustrated higher accuracy of NeuroVision in computing aneurysm volume compared with an approximation formula: percentage absolute errors were 4.50% ± 3.18% and 23.07% ± 17.60%, with maximal percentage absolute errors of 8.99% and 45.63%, respectively. Of 100 unruptured aneurysms, 20 recanalized and 12 were re-treated. Average volume embolization ratios of stable and re-treated aneurysms were 24.88% ± 5.91% and 20.50% ± 4.06%, respectively (P ≤ .01). The optimal volume embolization ratio cutoff point for re-treatment was < 19.15%, at which the Youden index was 0.50 (sensitivity, 58.33%; specificity, 87.50%; area under the receiver operating characteristic curve, 0.74).


CONCLUSIONS
The NeuroVision software provided accurate aneurysm volume measurements and may be a useful standardized tool to measure aneurysm size and volume, especially for multicenter clinical studies. Volume embolization ratio may be a valuable predictor of aneurysm occlusion changes.
From the Division of Endovascular Neurosurgery and Neurosurgery (H.T., T.I., H.A., M.E., K.I., Y.M.), Jikei University School of Medicine, Tokyo, Japan.
H
H
Takao
T
T
Ishibashi
T
T
Saguchi
H
H
Arakawa
M
M
Ebara
K
K
Irie
Y
Y
Murayama
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002533:Cerebral Angiography / Q000379:methods* / Q000592:standards*; D016208:Databases, Factual; D004621:Embolization, Therapeutic; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods* / Q000592:standards*; D002532:Intracranial Aneurysm / Q000000981:diagnostic imaging* / Q000473:pathology / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D008953:Models, Anatomic; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D012720:Severity of Illness Index; D012825:Silicon; D012985:Software Design
D012825:Silicon