MCQ Radiology Answer 09

The correct answer is D

Explanation:

Epidermoid cyst is a rare benign lesion of the testis (1%–2% of testicular lesions). Commonly the patients present between 2nd and 4th decades. Most of the epidermoid cysts are single and unilateral. Multiple or bilateral cysts are associated with Gardner syndrome, Klinefelter syndrome and cryptorchid testes. They are filled with laminated cheesy material. The clinical management is controversial and recently, organ-preserving surgery has been favored over traditional orchidectomy.Most patients present with painless mass, but a few complain of pain or discomfort.

US may show an echogenic centre surrounded by a hypoechoic ring and hyperechogenic rim, causing 'bull’s-eye' or 'target' lesion; or alternating hypoechoic and hyperechoic concentric rings, causing 'onion skin appearance'. The lesions are not vascular.MR shows low signal peripheral rim on both T1- and T2-weighted images and a circumferential high signal zone surrounding a low-signal central zone, or alternating concentric rings of low and high signal on T1- and T2-weighted images. On contrast, there is no enhancement.The central echogenic center may represent keratin debris and the concentric layeers may represent lipid and water containing materials. The squamous cell capsule causes hyperechoic rim.

The 'onion ring' appearance is charecteristic for an epidermoid cyst, although not pathognomonic. Simple and tunica albuginea cysts are anechoic. Tumors, abscesses and chronic inflammatory processes may have capsule, but are likely to show hypervascularity. Neoplasms usually enhance on Gd-enhanced MR. Hemorrhage may have heterogenous appearance on ultrasound.

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Category: Radiology MCQs