Investig Magn Reson Imaging.  2020 Mar;24(1):46-50. 10.13104/imri.2020.24.1.46.

MR Imaging of Radiation-Induced Lumbosacral Plexopathy, as a Rare Complication of Concomitant Chemo-Radiation for Cervical Cancer

• Hwang ET
• Son HM
• Kim JY
• Moon SM
• Lee HS

• KMID: 2508217
• DOI: http://doi.org/10.13104/imri.2020.24.1.46

Abstract

Radiation-induced lumbosacral plexopathy (RILSP) is an uncommon complication of pelvic radiotherapy that can result in different degrees of sensory and motor deficits. An age 59 female with cervical cancer, who had received combined chemotherapy and radiation therapy two years before, presented with bilaterally symmetric lowerextremity weakness and tingling sensation. The magnetic resonance imaging showed diffuse T2 bright signal intensity and mild enhancement along the bilateral lumbosacral plexus with no space-occupying masses. RILSP was diagnosed after the exclusion of malignant and inflammatory plexopathies.

Keyword

Radiation plexopathy; Lumbosacral plexus; Radiotherapy; Magnetic resonance imaging; Cervical carcinoma

Figure

• 

  Fig. 1. Contrast-enhanced hip MRI two years after the completion of CCRT. Coronal MRI at the first sacral foramen level reveals bilateral, symmetric, and diffuse T2 hyperintensity of LSP on coronal FS T2WI (a, arrows). The consecutive coronal FS T2WIs in the posterior direction demonstrated extensive involvement of LSP (b, c, arrows). Also, diffuse mild enhancement of the impacted LSP at the first sacral foramen level is depicted on T1WI (d, arrows) and contrast-enhanced T1WI (e, arrows). Note the asymmetric T2 signal change (pronounced on the right side) of the bilateral piriformis muscle (f, arrows). FS = fat suppressed; LSP = lumbosacral plexus

• 

  Fig. 2. The MR feature of the LSP before CCRT. The pre-CCRT pelvic protocol MRI (a, axial T2WI; b, oblique coronal T2WI perpendicular to the cervix) reveal normal bilateral LSP at both of the sciatic foramen (arrows). Newly defined diffuse thickening of the bilateral LSP after CCRT completion can be heightened by comparing the images acquired before and after the CCRT. LSP = lumbosacral plexus

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