Severe penile torsion of 180 degrees in an adult patient: a uro-radiological case report

Abstract

Penile torsion is the abnormal three-dimensional twisting of penile corporal bodies. It can be classified as mild, moderate, or severe, depending on the degree of torsion. Severe penile torsion (>90°) is a very rare condition, with an estimated incidence of 0.4%-1% among all penile torsion cases. Our patient was a 37-year-old man complaining of a 2-year history of lower urinary tract symptoms. These symptoms appeared after the patient sustained an iatrogenic injury during Foley catheter insertion. Physical examination incidentally revealed an obvious counterclockwise penile rotation of 180°. Several theories have been proposed to explain the etiology of penile torsion, including theories based on genetic factors, abnormal urethral development, and abnormal attachment of the dartos fascia to the skin. Penile torsion may be associated with other penile anomalies, including chordee, hypospadias, and epispadias; however, it is often detected as an isolated finding. Clinical examination is sufficient to confirm its diagnosis without the need for further imaging. While no standardized procedure has been indicated for all penile torsion cases, the severity of torsion and the presence of other anomalies determine the most suitable procedure. No reports on the imaging features of penile torsion (irrespective of the degree of torsion) are available. We present the first such report on the imaging features, including advanced magnetic resonance imaging findings, of a 180° penile torsion in an adult patient.

Keywords: magnetic resonance imaging; penile torsion; penis; stricture; urethra; urethrogram.

Figure 1

Gross image of the patient’s penis showing a 180˚ counterclockwise torsion

Figure 2

Left anterior oblique projection fluoroscopic static image from retrograde urethrography obtained after injection of a dilute solution of ioptridol (Xenetix 300) contrast in normal saline (1:2) through the urethral opening. The image shows normal opacification of the anterior urethra (bulbar and penile) and an irregular outline with a stricture at the posterior urethra (membranous urethra). No opacification of the prostate urethra is noted. The contrast does not exceed the urogenital diaphragm into the bladder.

Figure 3

Sagittal MRI scan of the penis. A. T1-weighted spin-echo sequence shows counterclockwisetunical narrowing and torsional twisting at the dorsal and ventral aspects of the proximal penile shaft (white arrows). No fascial discontinuity or uplifting of the superior dorsal vein are noted. B. T2-weighted spin-echo sequence shows heterogenous, multifocal, high-signal intensities distributed across all fascial layers at the dorsal aspect of the corpora (black arrow). C. T1-weighted post-contrast image with fat saturation sequence shows heterogeneous enhancement of the corpora and glans penis, corresponding to areas of chronic tissue ischemia (arrowhead). Additionally, the dorsal-covering fascial layers show intense enhancement secondary to contrast engorgement within the superior dorsal vein. A corresponding lack of central enhancement of the spongy urethra (asterisk) is noted, indicating necrosis as a sequela of chronic ischemia.

Figure 4

Axial MRI scan of the penis obtained without and with contrast. A, B, and C. T2-weighted sequences obtained at the root (A), body (B), and head (C) levels clearly show counterclockwise torsional twisting of the three erectile structures (corpora), starting from the root (A) and continuing in a 180˚ right-sided torsion. The corpora cavernosa (reversed right to left) and the corpus spongiosum (uplifted) are seen (arrow). D, E, and F. T1-weighted post-contrast image with fat saturation sequence shows heterogeneous enhancement of the corpora and glans penis, corresponding to areas of decreased perfusion and tissue ischemia (arrowheads).

Figure 5

Axial diffusion-weighted MRI scan of the penis. A. Diffusion-weighted sequence, at a high b value of 1,000, shows a small focus of high-signal intensity at the left corpus cavernosum at the body level (arrow). B. Apparent diffusion coefficient map shows the corresponding focus with a lower apparent diffusion coefficient in the same region of interest, reflecting an element of reduced perfusion.