Acute idiopathic segmental thrombosis of the corpus cavernosum. Imaging findings on MR

Clinical History

Male patient aged 20 with 7 days continuous perineal pain which increases during erection without response to analgesics treatment. He denied trauma, sexual injury, symptoms of urinary infection or drug treatments. Physical examination showed a painful perineal mass with the penis in a flaccid state (partial priapism).

Imaging Findings

MR showed an image on the left corpus cavernosum, hypointense on T2-weighted sequences (relative to the normal cavernous), faintly hyperintense on T1-weighted sequences, with no significant signal increase after administration of intravenous paramagnetic contrast agent. The process described expands the corpus cavernosum, shifting the midline to the contralateral side, measuring approximately 78 x 21 mm (Fig. 1).

Discussion

Background: The partial priapism is the most common manifestation of the unilateral partial thrombosis, characterised by affecting the proximal sector of the penis presenting a hardened perineal mass, being the remainder of the penis in a flaccid state [5]. Infrequently, discomfort or pain in the perineal region without palpable mass may also be present [3].
Clinical Perspective: The unilateral partial thrombosis of the corpus cavernosum is a rare entity and its aetiology is unclear so far, but repetitive microtrauma (cycling and vigorous sexual activity), marihuana abuse, smoking, blood diseases (sickle cell anaemia and congenital esferositosis) , history of priapism and diseases predisposing to blood hyperviscosity, particularly leukaemia and lymphoma have been associated with this disease [1, 2, 3].
Imaging Perspective: MRI visualisation of thrombus presents different types of signal intensity on T1 and T2, depending on the stage of degradation of haemoglobin. The affected cavernous body appears enlarged and usually compresses or displaces the contralateral one [6].
Outcome: The clinical presentation (palpable painful mass in the perineal region or partial priapism), Doppler ultrasound and MRI are useful at the time of noninvasive aetiologic diagnosis of this condition [7]. That is why the spontaneous signal hyperintensity in T1 suggests a period haematic content subacute (methaemoglobin) (4.6). The presumptive diagnosis was confirmed by surgical biopsy (Fig. 2). After 6 months an MRI control study showed a favourable radiologic (Fig. 3) and clinical evolution.

Differential Diagnosis List

Final Diagnosis

Acute idiopathic segmental thrombosis of the left corpus cavernosum

URL:	https://www.eurorad.org/case/10019
DOI:	10.1594/EURORAD/CASE.10019
ISSN:	1563-4086