Pictorial ReviewThe testis: the unusual, the rare and the bizarre
Introduction
Ultrasound is the method of choice in assessing the scrotum, providing detailed information and optimum resolution of both the testes and para-testicular structures, often enabling the sonographer to make a confident diagnosis. However, in order to do this it is important for the operator to be aware of unusual appearances of any normal testicular variant. The operator also needs to consider rarer pathology, as diagnosis of these conditions is often reliant on the sonographer being aware of their existence. Although by no means exhaustive, this article reviews some of the rare conditions and unusual appearances that may be encountered.
Section snippets
Polyorchidism (Fig. 1)
Polyorchidism is a rare anomaly described as the presence of more than two testes. The proposed mechanism is division of the genital ridge possibly by peritoneal bands around 4–6 weeks of embryonic life.1, 2 Based on the embryological development polyorchidism may be classified into four types3: type A: the supernumerary testis lacks either an epididymis or vas deferens. Type B: the supernumerary testis has an epididymis but no vas deferens, and the epididymis may be connected to the normal
Intra-testicular haematoma (Fig. 4)
Testicular rupture, extra-testicular haematoma and a haematocele are the most common sequelae of testicular trauma.21 Testicular rupture is a surgical emergency.22 An uncommon finding is an isolated intra-testicular haematoma.23 An intra-testicular haematoma has a variable appearance on ultrasound, with a temporal change in characteristics on repeat ultrasound, as would be expected.23, 24 A history of trauma to the scrotum should prompt the diagnosis, but this history is not always forthcoming.
Orchitis (Fig. 12)
This usually occurs in patients with epididymitis, giving rise to epididymo-orchitis. Primary orchitis without associated epididymitis is relatively rare but may be caused by human immunodeficiency virus (HIV) or mumps virus.55 The great range of appearances seen on ultrasound in acute orchitis may give rise to confusion. Initially oedema of the testis occurs with associated pain, ultrasound appearances are those of a diffuse low reflective pattern.56 The appearances then evolve to areas of
‘Snowstorm’ hydrocele (Fig. 15)
A hydrocele, a common finding, arises when serous fluid accumulates between the visceral and parietal layers of the tunica vaginalis and may be primary or secondary to scrotal disease.63 Septation may occur following infection or haemorrhage. Often, in the uncomplicated hydrocele, internal echoes produced by numerous small particles may be observed. This appearance is attributed to the presence of cholesterol crystals circulating within the fluid64 or to high protein content,65 which are of no
Conclusion
Ultrasound assessment of the scrotal contents is widely accepted as the first-line imaging technique for many common diseases. There are also numerous rare, unusual and often bizarre abnormalities for which ultrasound is again the appropriate investigation. The inherent high-resolution capabilities of ultrasound allow for exquisite demonstration of structures, surpassing that available with other imaging methods. Awareness on the part of the operator is essential for the correct interpretation
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Ultrasonography of the scrotum: Revisiting a classic technique
2021, European Journal of RadiologyCitation Excerpt :The spermatic cord is difficult to appreciate on grayscale imaging, assessed either on CDUS or in presence of fluid [5]. Five testicular appendages are seen, including the appendix testis, the appendix epididymis, the superior and inferior vas aberrans of Haller and the paradidymis [1,40,41]. The appendix testis (hydatid of Morgagni) is detected in up to 92% of men, in the groove between the testis and the epididymal head, measuring 1–7 mm, with a variable morphology, including oval, pedunculated, cystic or calcified.
Sarcoidosis-the greatest mimic
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