CASE 9098 Published on 09.03.2011

Scrotal pearl

Section

Uroradiology & genital male imaging

Case Type

Clinical Cases

Authors

Zilinskiene L1, Cleasby MJ2

1 Radiology Registrar, Good Hope Hospital, Heart of England NHS Trust, UK
2 Consultant Radiologist, Good Hope Hospital, Heart of England NHS Trust, UK

Patient

58 years, male

Categories
Area of Interest Genital / Reproductive system male ; Imaging Technique Ultrasound
Clinical History
A 58-year-old male patient was referred for a right groin and scrotal ultrasound scan due to a two months history of right iliac fossa and groin pain.
Imaging Findings
A 58-years-old male patient with no significant past medical history was reviewed in the outpatient clinic due to prolonged right groin pain. The clinical examination of the abdomen, right groin and both testes was unremarkable and the patient was referred for an ultrasound scan of the right groin and scrotum.

The ultrasound scan revealed no abnormalities in the right inguinal region, and no lymphadenopathy was seen in the groin. Both testes were normal in size, shape and echo-pattern (Fig. 1) with normal intra-testicular vascular flow.

Several small cysts and cystic appendages were seen in the rete-testis and epididymal heads bilaterally. A rounded, hyper-echoic, 5 mm extra-testicular nodule was seen freely mobile in the right hemiscrotum (Fig. 2). It cast an acoustic shadow and was thought to represent a separated epididymal appendage, which has calcified to form a scrotal calculus, or scrotal pearl.
Discussion
Scrotal calculi, scrotoliths, or scrotal pearls are mobile calcific bodies located between the layers of tunica vaginalis. First described in 1935, they are found in about 2.5% of the general male population, and may be solitary or multiple.

Although the exact aetiology of scrotal pearls is unclear, they are thought to result from either inflammation within the tunica vaginalis, or the torsion and detachment of the appendix testis or epididymis. Various traumatic or inflammatory factors cause damage to the layers of tunica vaginalis with obstruction of the lymph drainage. Subsequent reabsorbtion of calcium, cholesterol and fibrin results in calculus formation.

Ultrasound is the modality of choice for diagnosing scrotal pearls, as they may be difficult to palpate, especially in the presence of a hydrocoele. They are identified as discrete, well defined, hyper-echoic loose bodies which may cast an acoustic shadow, or have a ‘comet tail’ artefact. An attachment to the membranes of the tunica vaginalis may occasionally be seen. The calculi themselves are of no large clinical significance and are completely benign lesions not requiring any treatment or follow up.

Calcification within the extra-testicular portion of the scrotum is a more common condition as compared to intra-testicular calcification, and usually represents a benign disease.

Differential diagnosis of extra-testicular calcific lesions includes calcification of the epididymis, sperm granuloma or tunica vaginalis (linear plaque). Calcification of the epididymis is a common finding in chronic epididymitis and occurs secondary to inflammatory / granulomatous conditions such as tuberculosis or trauma. Appendix testis and appendix epididymis may both calcify without torsion and separation, and are recognised by their characteristic shape and position.

Differential diagnosis of calcified intra-testicular lesion includes a post-traumatic change, calcified benign Sertoli or Leydig-cell tumour, or a regressed ‘burnt out’ germ cell testicular tumour.
Differential Diagnosis List
Scrotal calculus, or scrotal pearl.
Epididymal calcification
Sperm granuloma
Calcification of tunica vaginalis
Final Diagnosis
Scrotal calculus, or scrotal pearl.
Case information
URL: https://eurorad.org/case/9098
DOI: 10.1594/EURORAD/CASE.9098
ISSN: 1563-4086