Value of Multimode Sonography for Assessment of Pelvic Lipomatosis Compared with Computed Tomography.

OBJECTIVES:To assess imaging features of pelvic lipomatosis with a multimode sonographic technique, including 2-dimensional (2D) grayscale sonography, 3-dimensional (3D) sonography, and transrectal sonography, and compare its diagnostic features with those of computed tomography (CT).METHODS:In this study, 7 patients with different clinical manifestations were incidentally discovered by 2D sonography and followed by 3D and transrectal sonography before CT was performed for comparison. The urinary tract morphologic characteristics, bladder shape, and amount and distribution of perivesical or perirectal fatty tissue in all 7 patients were evaluated by both imaging modalities. Ten healthy participants were recruited and imaged as a control group.RESULTS:The following sonographic features were shown in all 7 patients: (1) bilateral hydroureters and hydronephrosis on 2D sonography; (2) bladder shifting anteriorly and superiorly on 2D sonography; (3) nonvisualization of the prostate through the bladder window on transabdominal scanning and nonvisualization of the bladder when the prostate was scanned by transrectal sonography; (4) bladder elongation in the craniocaudal dimension, which appeared as a gourd or pear shape on 3D sonography; and (5) excessive fat accumulation between the prostate and rectum as well as in perivesical or perirectal regions on 2D and transrectal sonography. Computed tomography in these patients confirmed the sonographic findings, with evidence of hydronephrosis, bladder location shift and elongation, and excessive fitty tissue with extrinsic compression.CONCLUSIONS:This preliminary study has shown that the application of a multimode sonographic technique (ie, 2D, 3D, and transrectal sonography) can provide unique evidence and imaging features of pelvic lipomatosis, which are comparable with CT for making a suggestive diagnosis of pelvic lipomatosis. Thus, multimode sonography may be the modality of choice for assessment of patients with a suspicion of lipomatosis.