Bilateral intrauterine testicular torsion: ultrasound findings

Clinical History

Male presenting at birth with bilateral tough scrotal swelling with widespread bruising (Fig. 1). Normal development of male external genitalia. Aporetic. General condition is good.

Imaging Findings

Testicular ultrasound: bilateral thickening of the scrotal tunics (Fig. 2). Left testis (15 x 14 x 18 mm) markedly destructured with multiple anechoic intraparenchymal ulcerations, hypoechoic peripheral ring and thickening of the albuginea tunic. Organised intrascrotal effusion (Fig. 3). Lack of intraparenchymal blood flow (Fig. 4). Right testis (15 x 10 x 10 mm) with less severe similar findings and intraparenchymal vascular spots. Intrascrotal blood effusion with sediment (Fig. 5).
Transfontanellar ultrasonography: normal findings.

Discussion

Intrauterine torsion of the testis (IUTT) is a rare pathology which afflicts 1/7500 newborns [1]. It can be unilateral with no predilection of laterality or, in 10% of cases, bilateral [2]. The increasing number of reported cases with bilateral IUTT supports a predisposing factor [3]. The torsion is normally extravaginal [4] and, in most cases, occurs between the 34th and the 36th gestational week or during labour [5]. The aetiology is unknown but the very mobility of the neonatal tunica vaginalis within the scrotum, difficult labour, breech presentation, high birth weight, over reactive cremasteric reflex and multiparity may be involved [5, 6].
Infant presents at birth with hard, swollen, non-tender tests, often asymptomatic. The intrauterine bilateral torsion may have occurred asynchronously with different clinical appearance, although both tests are damaged.
Prenatal US findings include hydrocele, enlarged testis with hyperechoic parenchymal spot or disarranged texture, hypoechoic peripheral ring [5] but prenatal diagnosis is rare.
Colour Doppler Ultrasound (CD-US) is the method of choice to confirm the diagnosis. It shows a decreased or absent vascular flow. Exact timing and duration of torsion can’t be defined but in the acute phase, US shows enlarged testis and epididymis, surrounded by organised haematocele. Subsequently the testis eco-structure becomes heterogeneous with a central hypoechoic area and a hypoechoic peripheral ring corresponding to infarction and necrosis. In chronic phase calcifications of the transition zone between residual testicular parenchyma and tunica albuginea can appear [2].
Bilateral IUTT represents a surgical emergency because of the risk of anorchia. The management is controversial. In our case left orchiectomy was performed because the testicle appeared grossly necrotic and nonviable (fig. 6). Detorsion and orchiopexy of the right testicle, which appeared ischaemic but not frankly necrotic (Fig. 7), were performed. Intraoperative CD-US showed a slight increase of the blood flow.
Some authors [5] suggest to replace the gangrenous testis after derotation because the endocrine cells are resistant to ischaemia.
Prognostic data about fertility in bilateral IUTT are insufficient due to the long-term follow-up.
In conclusion, clinical and CD-US findings are highly suggestive of IUTT and permit to act promptly, reducing the risk of anorchia, especially in cases of bilateral IUTT.

Differential Diagnosis List

Final Diagnosis

Bilateral intrauterine testicular torsion

URL:	https://eurorad.org/case/15293
DOI:	10.1594/EURORAD/CASE.15293
ISSN:	1563-4086