TABLE 1.
List of original studies that investigated infancy, childhood and adolescence US aspects of main scrotal pathologies
| Author, year of publication and journal | Caseload | Study populations’ characteristics | Scrotal disease | US findings |
|---|---|---|---|---|
| Cain, 1996, J Urol. | 64 patients | Mean age 4.5 years (0.5 to 17 years) | Cryptorchidism | Scrotal‐inguinal ultrasound correctly identified 40 of the 42 inguinal testes (95% sensitivity), 7 of the 21 atrophic inguinal testes (33% sensitivity) and 1 of the 11 intra‐abdominal testes (9% sensitivity). |
| Kollin, 2012, J Clin Endocrinol Metab. | 225 patients | Mean age 1.87 years (0.7 to 3 years) | Cryptorchidism | Correlation between US‐obtained testicular volume and number of germ and Sertoli cells in cryptorchid patients who underwent testicular biopsies. This randomized controlled study compared the outcome of surgery for congenital cryptorchidism at 9 months or 3 years of age: at both ages, testicular volume correlated to the number of germ and Sertoli cells. |
| Jedrzejewski, 2012, Early Hum Dev. | 1448 patients | Mean age 1.4 years (0.7 to 3 years) | Cyptorchidism and hydrocele | In this scrotal ultrasound screening program performed on boys up to 3 years old, abnormalities in scrotal ultrasound were found in 20.1% of boys. Undescended, cryptorchid testes were found in 4.8% of patients, mobile testicle in 7.6% and hydrocele in 2.8%. |
| Cuervo, 2009, J Pediatr Surg. | 9 patients | Newborns | Hydrocele | Ultrasound was useful to confirm the initial suspicion of the presence of an abdomen‐scrotal hydrocele. Hydrocele appeared as an hourglass‐shaped cystic mass with homogeneous anechoic content. |
| Chmelnik, 2010, Pediatr Surg Int. | 25 patients | Mean age 9.8 (0.3 to 15 years) | Testicular torsion | TT was detected in 16 out of 25 patients. The Authors, in addition to the absence of blood flow, detected focal hyper‐/hypoechogenicity in 12.5% of patients, diffuse hyper‐/hypoechogenicity in 31.3% of patients and a normal echogenicity in 56.3%. US features changed over time: the time span since torsion developed determined testicular viability. No testis with focal hyper/ipoechogenicity could be saved. The mean volume of the affected testes was 6.0 ± 6.9 mL, significantly higher than the mean volume of the non‐affected ones (3.3 ± 3.7 mL). |
| Liang, 2012, Am J Roentgenol. | 266 patients | Mean age 12.2 years (from 1 month to 17 years) | Testicular torsion |
TT was detected in 29 out of 266 patients, with absent blood flow seen by color Doppler. The affected testes were found to have a significantly higher incidence of decreased flow and heterogeneous echogenicity. Similarly, a higher incidence of decreased flow also in the epididymis and enlarged scrotal size were found in testicular torsion patients. |
| Lev, 2015, Eur J Endocrinol. | 19 patients | Mean age 9.4 years (3 to 14 years) | Torsion of the testicular appendix |
It appeared as an oval, avascular mass with increased, low, or mixed echogenicity, which could be located between the head of the epididymis and the upper pole of the testis. Torsion of the testicular appendix is often accompanied by hydrocele, enlargement of the head of the epididymis and surrounding hyperemia. The lesions had a maximal diameter ranging from 5.8 to 15.6 mm (mean 9.5 mm). |
| Karmazyn, 2009, Pediatr Radiol. | 47 patients | Mean age 9.6 years (from 1 month to 17 years) | Epididymitis | Increased epididymal blood flow was seen in all children. Epididymal enlargement was bilateral in 4 cases, right‐sided in 23 cases, and left‐sided in 20 children. Epididymal enlargement was marked in 14 children, moderate in 26 children, and mild in 7 children. Testicular swelling and hydrocele could also occur. |
| Caballero Mora, 2012, An Pediatr (Barc). | 15 patients | Mean age of the patients was 9.7 years (0.6 months to 16 years) | Testicular cancer | US detects testicular neoplasms in almost 100% of cases. Benign tumours appeared as well‐defined masses with demarcated borders and poor vascularity. Epidermoid cysts appeared as well‐defined intratesticular lesions with a central hypoechogenic area surrounded by a hyperechogenic ring. Yolk sac tumours have a more solid, hypoechogenic, homogeneous appearance. |
| Song, 2018, J Ultrasound Med. | 21 patients | Mean age 16.2 months (0.8 to 5 years) | Yolk‐sac tumor | Grayscale US images showed focal lesions in 14 out of 21 cases. The focal lesions were purely solid in 10 patients or solid with cystic components in 4 patients. The mixed focal lesions (both solid and with cystic components) were ovoid, with randomly distributed multiple anechoic spaces, which were variable in number, size, and shape. In most of cases homogeneous echo texture (43%) and increased blood flow (85.7%) were found. |
| Epifanio, 2014, Urology | 7 patients | Mean age 8.1 months (from the date of birth to 4 years) | Teratoma | The US findings were heterogeneous: cystic (1 case), multi‐cystic (2 cases), solid‐cystic (1 case), solid containing larger or smaller calcifications (2 cases), and focal calcification (1 case). All the solid lesions had few vessels in the interior of the lesions. Testicular teratoma could be single, multiseptated, small, or large, and could contain diffuse or localized calcifications. Finally, the gonad could also have an increased or a normal volume. |
| Posey, 2010, J Urol. | 1765 patients | Patients were grouped into 5‐year age intervals, including less than 5, 5 to 10, 10 to 15 and greater than 15 years | Epididymal cysts | This retrospective study on the occurrence of epididymal cysts showed an increased incidence with age and a correlation between epididymal cysts and testicular size, which resulted larger in boys with cysts. |
| Christman, 2014, J Urol. | 73 patients | Mean age 15.5 years (13.2 to 17.7 years) | Varicocele in adolescence | In this retrospective study on adolescents with varicocele evaluated by serial scrotal ultrasound, testicular volume was shown to predict total motile count at the end of adolescence but not throughout. |
| Zampieri, 2008, J Urol. | 2107 patients | Mean age 13 years (10 to 16 years) | Varicocele in adolescence | This longitudinal follow‐up observational study determined the prognostic value of clinical examination and US in predicting the risk of progression, time to worsening and the final outcome of varicocele in adolescence. |
| Cooper, 2014, Radiology | 3370 patients | Mean age 11.0 years (0.6 to 17.9 years) | Testicular microlithiasis | In this large US study, TM had a prevalence of 2% in boys who underwent scrotal US. It was most commonly bilateral, classic type, and stable at follow‐up. There was a significant association of TM and testicular tumors. Malignant tumors were seen only in adolescent boys. |
| Trout, 2017, Radiology | 37863 patients | Mean age 11.1 years (6.4 to 15.8 years) | Testicular microlithiasis |
In this retrospective study on a large pediatric population the strong association between TM and testicular neoplasia was assessed. Primary testicular tumors of any type were present in 4.64% of boys with TM. Malignant germ cell tumors were present in 2.83% of boys with TM and sex cord–stromal tumors were identified in 0.46% of boys with TM. |
Abbreviations: TM, testicular microlithiasis; TT, testicular torsion; US, ultrasound