Male infertility: the role of imaging in diagnosis and management

Abstract

The investigation of male infertility is assuming greater importance, with male factors implicated as a causal factor in up to half of infertile couples. Following routine history, examination and blood tests, imaging is frequently utilised in order to assess the scrotal contents for testicular volume and morphology. Additionally, this may give indirect evidence of the presence of possible reversible pathology in the form of obstructive azoospermia. Further imaging in the form of transrectal ultrasound and MRI is then often able to categorise the level of obstruction and facilitate treatment planning without resort to more invasive imaging such as vasography. Ultrasound guidance of therapy such as sperm or cyst aspiration and vasal cannulation may also be performed. This article reviews the imaging modalities used in the investigation of male infertility, and illustrates normal and abnormal findings that may be demonstrated.

Figure 1

(a) Normal longitudinal ultrasound image of the testis, demonstrating a uniform texture and reflectivity with a length of 5.0 cm (normal 3.5–5.0 cm). Volume measurement is calculated as length×height×width×0.51. (b) Longitudinal ultrasound image of a small (length 2.5 cm) testis with an abnormal texture and reflectivity in a patient being investigated for infertility.

Figure 2

Normal ultrasound anatomy of the seminal vesicles and vasa deferentia. Transverse image from a transrectal ultrasound image, obtained superior to the prostate, shows symmetric seminal vesicles (short arrows) and more medially located vasa deferentia (long arrows).

Figure 3

Ultrasound evaluation of a normal cavernosal artery response post intracavernosal injection of prostaglandin E1. Reversal of end diastolic velocity at 15 min is demonstrated, with a peak systolic velocity measured at 141.5 cm s⁻¹ (normal >35 cm s⁻¹) and an end diastolic velocity measured at −27.9 cm s⁻¹.

Figure 4

Normal T₁ (a) and T₂ (b) weighted axial MR images through the prostate (long arrow). The peripheral zone is of high signal on the T₂ weighted images (short arrows).

Figure 5

A difficult and less frequently performed right testicular vein embolisation, as the right testicular vein drains directly into the inferior vena cava. (a) An 0.018 inch coaxial microcatheter (arrow) is used on the right owing to the sharp reverse angle of the testicular vein and the inferior vena cava. Collaterals are seen at the mid-testicular vein level (short arrow). (b) Coil embolisation (arrows) of the testicular vein with successful obliteration of collateral filling.

Figure 6

Heterogeneous testis with associated ectasia of the rete testis (short arrows) and dilated body of the epididymis (long arrow) in keeping with long-standing obstruction.

Figure 7

A transrectal ultrasound examination demonstrating calcification within the ejaculatory duct (short arrow) with dilatation of the vas deferens proximally (long arrow).

Figure 8

Scrotal ultrasound demonstrating thickening and enlargement of the epididymal body (arrow) in a case of infective epididymitis. The testis is spared from the infective process.

Figure 9

(a) Longitudinal scan demonstrating a small testis with a heterogeneous echo-texture and a varicocoele (arrows) in a patient being investigated for infertility. (b) Focal dilatation of the epididymis (arrow) in keeping with chronic obstruction secondary to infection.

Figure 10

Longitudinal ultrasound of the epididymis demonstrating the classical appearance associated with a vasectomy (long arrow) and an additional less well appreciated view of the dilated vas deferens (short arrows).

Figure 11

Bilateral thickening of the vas deferens on a transrectal ultrasound examination in keeping with vesiculitis (arrows).

Figure 12

Small cyst lying within the midline within the prostatic utricle (arrow). This returns a low signal on the T₁ weighted images (not shown) and a high signal on the T₂ weighted images in keeping with cystic dilatation of the prostatic utricle.

Figure 13

Ultrasound image of the left groin in a patient with testicular maldescent demonstrates a heterogeneous, with focal areas of low reflectivity and a small testis in keeping an infracted undescended testis within the inguinal canal.

Figure 14

Scrotal ultrasound image demonstrating global reduction in testicular volume and reflectivity on the right (arrow) on this “spectacle” view of both the testes.

Figure 15

A severely affected testis following orchitis, demonstrating mixed reflectivity with pockets of high reflectivity likely to represent areas of infarction and haemorrhage.

Figure 16

(a) On greyscale imaging a varicocoele is seen as serpiginous tubules inferior to the testis (arrow). (b) Colour flow Doppler confirms flow within the varicocoele (arrow).

Figure 17

Longitudinal ultrasound image of a testicular mass demonstrating increased Doppler flow within the lesion; a histologically proven seminoma.