Volume Measurement of the Intracranial Aneurysm: A Discussion and Comparison of the Alternatives to Manual Segmentation

다국어 초록 (Multilingual Abstract)

Objective : Several modalities are available for volumetric measurement ofthe intracranial aneurysm. We discuss the challenges involved in manualsegmentation, and analyze the application of alternative methods usingautomatic segmentation and geometric formulae in measurement of aneurysmvolumes and coil packing density.
Methods : The volumes and morphology of 38 aneurysms treated withendovascular coiling at a single center were measured using three-dimensionalrotational angiography (3DRA) reconstruction software using automaticsegmentation. Aneurysm volumes were also calculated from theirheight, width, depth, size of neck, and assumed shape in 3DRA imagesusing simple geometric formulae. The aneurysm volumes were dichotomizedas "small" or "large" using the median volume of the studied population(54 mm3) measured by automatic segmentation as the cut-off valuefor further statistical analysis.
Results : A greater proportion of aneurysms were categorized as being"small" when geometric formulae were applied. The median aneurysm volumesobtained were 54.5 mm3 by 3DRA software, and 30.6 mm3 usingmathematical equations. An underestimation of aneurysm volume with aresultant overestimation in the calculated coil packing density (p = 0.002)was observed.
Conclusion : Caution must be exercised in the application of simple geometricformulae in the management of intracranial aneurysms as volumesmay potentially be underestimated and packing densities falsely elevated.
Future research should focus on validation of automatic segmentation involumetric measurement and improving its accuracy to enhance its applicationin clinical practice.

참고문헌 (Reference)

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