title: Whole Abdominal Wall Segmentation using Augmented Active Shape Models (AASM) with Multi-Atlas Label Fusion and Level Set.
abstract: The abdominal wall is an important structure differentiating subcutaneous and visceral compartments and intimately involved with maintaining abdominal structure. Segmentation of the whole abdominal wall on routinely acquired computed tomography (CT) scans remains challenging due to variations and complexities of the wall and surrounding tissues. In this study, we propose a slice-wise augmented active shape model (AASM) approach to robustly segment both the outer and inner surfaces of the abdominal wall. Multi-atlas label fusion (MALF) and level set (LS) techniques are integrated into the traditional ASM framework. The AASM approach globally optimizes the landmark updates in the presence of complicated underlying local anatomical contexts. The proposed approach was validated on 184 axial slices of 20 CT scans. The Hausdorff distance against the manual segmentation was significantly reduced using proposed approach compared to that using ASM, MALF, and LS individually. Our segmentation of the whole abdominal wall enables the subcutaneous and visceral fat measurement, with high correlation to the measurement derived from manual segmentation. This study presents the first generic algorithm that combines ASM, MALF, and LS, and demonstrates practical application for automatically capturing visceral and subcutaneous fat volumes.
authors.affiliation: Electrical Engineering, Vanderbilt University, Nashville, TN, USA 37235.
authors.forename: Zhoubing
authors.initials: Z
authors.lastname: Xu
authors.affiliation: General Surgery, Vanderbilt University Medical Center, Nashville, TN, USA 37235.
authors.forename: Rebeccah B
authors.initials: RB
authors.lastname: Baucom
authors.affiliation: Radiology and Radiological Science, Vanderbilt University, Nashville, TN, USA 37235.
authors.forename: Richard G
authors.initials: RG
authors.lastname: Abramson
authors.affiliation: General Surgery, Vanderbilt University Medical Center, Nashville, TN, USA 37235.
authors.forename: Benjamin K
authors.initials: BK
authors.lastname: Poulose
authors.affiliation: Electrical Engineering, Vanderbilt University, Nashville, TN, USA 37235; Radiology and Radiological Science, Vanderbilt University, Nashville, TN, USA 37235.
authors.forename: Bennett A
authors.initials: BA
authors.lastname: Landman
keywords: abdominal wall; active shape model; computed tomography; level set; multi-atlas label fusion