title: Dual registration of abdominal motion for motility assessment in free-breathing data sets acquired using dynamic MRI.
abstract: At present, registration-based quantification of bowel motility from dynamic MRI is limited to breath-hold studies. Here we validate a dual-registration technique robust to respiratory motion for the assessment of small bowel and colonic motility. Small bowel datasets were acquired in breath-hold and free-breathing in 20 healthy individuals. A pre-processing step using an iterative registration of the low rank component of the data was applied to remove respiratory motion from the free breathing data. Motility was then quantified with an existing optic-flow (OF) based registration technique to form a dual-stage approach, termed Dual Registration of Abdominal Motion (DRAM). The benefit of respiratory motion correction was assessed by (1) assessing the fidelity of automatically propagated segmental regions of interest (ROIs) in the small bowel and colon and (2) comparing parametric motility maps to a breath-hold ground truth. DRAM demonstrated an improved ability to propagate ROIs through free-breathing small bowel and colonic motility data, with median error decreased by 90% and 55%, respectively. Comparison between global parametric maps showed high concordance between breath-hold data and free-breathing DRAM. Quantification of segmental and global motility in dynamic MR data is more accurate and robust to respiration when using the DRAM approach.
authors: Centre for Medical Imaging, 3rd Floor East, 250 Euston Road London NW1 2PG, UCL Division of Medicine, London, UK.
authors: A
authors: A
authors: Menys
authors: V
authors: V
authors: Hamy
authors: J
authors: J
authors: Makanyanga
authors: C
authors: C
authors: Hoad
authors: P
authors: P
authors: Gowland
authors: F
authors: F
authors: Odille
authors: S A
authors: SA
authors: Taylor
authors: D
authors: D
authors: Atkinson
mesh_terms: D000005:Abdomen / Q000502:physiology*; D000328:Adult; D016477:Artifacts; D003106:Colon / Q000502:physiology; D005260:Female; D005769:Gastrointestinal Motility; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D007421:Intestine, Small / Q000502:physiology; D008279:Magnetic Resonance Imaging; D008297:Male; D009068:Movement; D012119:Respiration; D055815:Young Adult