Radiology, Vol 185, 105-108, Copyright © 1992 by Radiological Society of North America
Lateral arcuate ligaments of the diaphragm: anatomic variations at abdominal CT
PM Silverman, C Cooper and RK Zeman
Department of Radiology, Georgetown University Hospital, Washington, DC 20007.
The authors have occasionally observed nodular areas abutting the lateral
diaphragmatic surface and extending into the posterior pararenal space on
computed tomographic (CT) scans. Review of the anatomy literature revealed
that this finding represents inferolateral extension of the lateral arcuate
ligaments, which reflect over the quadratus lumborum muscles to fuse with
the diaphragm. CT scans from 100 consecutive patients were reviewed to
determine the frequency, relationship to habitus, and appearance of this
finding. Nodularity was found in five patients (bilateral in three,
unilateral in two). The average size was 9.4 mm in the transverse plane,
6.3 mm in the anteroposterior plane, and 4.3 cm in the cephalocaudal plane.
The extent of retroperitoneal fat was normal in all five patients. In one
patient, there were easily visible lobulations; three patients had
prominent lobulations, and one patient had few lobulations. It is important
to recognize this anatomic variant to avoid confusion with disease.
