12/04/2021

Scrotal Ultrasound

Scrotal Ultrasound

Paul S. Sidhu CONTENT Professor of Imaging Sciences King’s College Hospital London

Scrotal Ultrasound

Lecture Content

• Background Anatomy • Normal Variants • Extra-testicular pathology • Intra-testicular pathology • Global Abnormalities Scrotal Ultrasound • New US techniques ANATOMY

Scrotal Ultrasound Scrotal Ultrasound Anatomy Vascular Anatomy

• Testicular artery Low vascular resistance Broad systolic peak High diastolic flow • Cremasteric artery and artery to ductus deferens /Peri-testicular tissues Narrower systolic peak Low diastolic flow

Aziz ZA, Satchithananda K, Khan M, Sidhu PS. High Frequency Colour Doppler Ultrasound of the Arteries: Resistive Index Variation in a Cohort of 51 Healthy Men. Journal of Ultrasound in Medicine 2005;24:905-909.

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Scrotal Ultrasound Vascular Anatomy

• Pampiniform plexus • Cremasteric plexus • Testicular vein

Scrotal Ultrasound NORMAL VARIANTS

Scrotal Ultrasound Scrotal Ultrasound Normal Variants Normal Variants

Torsion of an Appendix Testis • Testicular appendages are remnants of the paramesonephric ducts, found at the upper pole of the testes in a groove between the testis and the head of the • Age range 7-12 years epididymis. • ‘Blue dot’ sign on a fair skin. • Similar reflectivity to the epididymal head and ovoid shaped, may be cystic. • Torsion of a testicular appendix is a common cause for scrotal pain in children. • Appendix is usually sessile but may be pedunculated and sometimes calcifies. • The presenting features of appendicular torsion and testicular torsion are often similar, • Seen in 92% of post mortems, 90% of cases are appendix testis • Infarcted appendix may form a scrotal pearl though pain localised to the upper pole of the and a tender nodule are suggestive of a torsed appendix. • Differentiation is important as an appendicular torsion may be managed conservatively. • Ultrasound appearances are variable but usually there is a rounded mass at the superior aspect of the testicle with increased surrounding color Doppler flow and an associated hydrocele. Testicular Appendages

Paradidymis (Organ of Giraldes) Appendix testis (Hydatid of Mogagni) Appendix epididymis Vas abberrrans of Haller 12 year old boy with 7 day history of left testicular pain with a ‘blue dot’ sign Sellars MEK, Sidhu PS. Ultrasound Appearances of the Testicular Appendages. European Radiology 2003;13:127-135.

Scrotal Ultrasound Scrotal Ultrasound Normal Variants Normal Variants • Composed of numerous seminiferous serpiginous tubules which drain to the epididymal head. • Dilatation of the rete testis is common and seen in patients over 50yrs. • Associated with epididymal obstruction, a spermatocele or dilated efferent spermatic ducts. ‘Two-tone’ Testis • The cystic structures usually measure a few millimetres but as large as 7cm.

• This describes the appearance of a normal testis where the testis is divided into by an intra-testicular artery. • The portion nearest to the probe is of normal reflectivity whereas the portion distal to the probe is of decreased reflectivity. • The appearance is thought to be due to a refractive artefact caused by scanning obliquely through the walls of the artery.

68 year old man with obstructive azoospermia, which is responsible for 5% of male infertility

Bushby LH, Sellars ME, Sidhu PS. The ‘Two-Tone’ Testis: Spectrum of Ultrasound Appearances. Clinical Radiology 2007;62:1119-1123. Sellars MEK, Sidhu PS. Pictorial review: ultrasound appearances of the rete testis. European Journal of Ultrasound 2001;14:115-120.

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Scrotal Ultrasound Scrotal Ultrasound Normal Variants Normal Variants

Polyorchidism

• A rare abnormality described as the presence of three or more testes. SplenogonadalFusion • Occurs following division of the genital ridge at 4-6 weeks of embryonic life. • Reproductive potential of the supernumerary testis is dependant on any attachment • Splenogonadal fusion is a rare congenital abnormality where an to a draining vas and epididymis. accessory spleen exists within the fused to the testis. • There may be maldescent of the supernumerary testis or the normal testicle and • There are two types, continuous and discontinuous. In the the condition is associated with torsion, inguinal hernia and cryptorchidism. RIGHT continuous type the spleen is connected to the accessory spleen by a cord. • The condition usually presents as a painless mass • Diagnosis is problematic as often the accessory spleen is • The ultrasound features are a well defined rounded lump occurring either at the confused for a testicular tumour. superior or inferior aspect of the ipsilateral testicle with identical reflectivity and • If suspected a sulphur colloid scan is diagnostic demonstrating blood flow. tracer uptake in the spleen and accessory splenic tissue. • The length of the supernumerary testes and ipsilateral testicle added together equates to the length of the contra lateral testicle. • The management is conservative unless there are associated complicated features.

LEFT

Rajbabu K, Morel JC, Thompson PM, Sidhu PS Multi-cystic (rete testis) supernumerary testis in polyorchidism with underlying microlithiasis: Ultrasound features. Australasian Radiology 2007;51:B56-B58. Stewart VR, Sellars M, Somers S, Muir G, Sidhu PS. Splenogonadal fusion. B-Mode and Color Doppler Sonographic Appearances. J Ultrasound Med 2004; 23:1087-1090.

Scrotal Ultrasound Extra-testicular Pathology

The para-testicular space contains the epididymis, spermatic cord and the cavity and is affected by a variety of inflammatory or tumoral entities. Differential diagnosis based on US criteria is frequently problematic, as the findings are non-specific. Some general rules apply;

i) unlike testicular lesions, extra-testicular entities are usually benign in the adult

ii) the first steps to accurate diagnosis include careful localization of the lesion and assessment of its consistency (solid or cystic)

Scrotal Ultrasound iii) MRI is useful for tissue characterization of lesions suspected to contain fat, but surgical biopsy will often provide the definite diagnosis. EXTRA-TESTICULAR PATHOLOGY iv) Contrast-enhanced ultrasound (CEUS) has been applied with limited experience indicating a narrow role, primarily for the differential diagnosis of echogenic cystic entities and the delineation of a necrotic abscess from a solid neoplasm.

Vasileios Rafailidis, Dean Y. Huang, Paul S. Sidhu. Para-testicular lesions: Aetiology and Appearances on Ultrasound. Andrology in press 2021

Scrotal Ultrasound Scrotal Ultrasound Extra-testicular Pathology Extra-testicular Pathology

Benign entities Malignant entities

• Hydrocele • Rhabdomyosarcoma • Inflammatory lesions: epididymitis and abscess • Liposarcoma • Epididymal and spermatic cord cyst • Leiomyosarcoma • Fibrous pseudo-tumour • Malignant fibrous histiocytoma • Lipoma • Mesothelioma • Adenomatoid tumour • Lymphoma and leukemia • Leiomyoma • Papillary cystadenoma of the epididymis • Para-testicular hemangioma • Hernias A transverse image through the right A longitudinal image through the left scrotal sac, A longitudinal image through the scrotal sac, with the testis (star) demonstrating a normal testis (star) with a • Scrotal calculi right scrotal sac following a road surrounded by a septated pyocoele hydrocoele surrounding the upper aspect of the • Varicocele traffic accident. The testis (star) is (arrowheads and displaced posteriorly by testis, and with an irregular walled abscess within displaced inferiorly by a large thickened inflamed epididymis (long the thickened epididymis and with echogenic debris septated haematocele (arrow). arrow). There is scrotal wall thickening present (arrows). (short arrows). Rafailidis V, Robbie H, KonstantatouE, Huang DY, Deganello A, Sellars ME, Cantisani V, Isidori AM, Sidhu PS. Sonographic imaging of extra-testicular focal lesions: Comparison of grey-scale, colour Doppler sonography and contrast-enhanced ultrasound (CEUS) Ultrasound 2016;24:23-33

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Scrotal Ultrasound Scrotal Ultrasound Extra-testicular Pathology Extra-testicular Pathology

A longitudinal image through the A longitudinal image through the left scrotal right scrotal sac, with the testis (star) A longitudinal image through the A longitudinal image through the left sac, with the testis (star) superior to a A longitudinal image through the right scrotal A longitudinal image through the left scrotal inferior to a simple cyst of the right scrotal sac, with the testis scrotal sac, with the testis (star) predominantly septated lesion with linear sac, seen at the upper aspect of the testis is a sac, a heterogenous testis (star) is displaced epididymis (long arrow). There is (star) superior to a well superior to a well circumscribed low areas of high reflectivity; a papillary mixed reflective area (arrows); a low grade superiorly by a mixed reflective lesion posterior acoustic enhancement circumscribed high reflectivity reflectivity adenoma (arrow). cystadenoma of the epididymis (arrows). liposarcoma. (arrows), with patchy areas of increased present (short arrows) distal to the lipoma (arrow). reflectivity; epididymal lymphoma. cystic structure, confirming the fluid content.

Scrotal Ultrasound Scrotal Ultrasound Extra-testicular Pathology Varicoceles

Sarteschi et al Standing and [1] [2] [3] [4] [5] (1993) Supine Inguinal reflux Supra-testicular Peri-testicular Enlarged vessels Enlarged vessels only during varicosities with reflux only during in supine and in supine and Valsalva in not reflux only during Valsalva in standing position, standing position, enlarged vessels Valsalva enlarged vessels. with increasing with caliber not Visible but not caliber with increasing with dilated vessels Valsalva. Reflux at Valsalva. Reflux at when supine. rest, increasing rest, not Enlarged when during Valsalva. increasing during standing Possible testicular Valsalva. hypotrophy Testicular hypotrophy. Intratesticular varices may be present

Sarteschi LM, Paoli R, Bianchini M, Menchini Fabris GF. (1993) Lo studio del varicocele con eco-color-Doppler. G Ital Ultrasonologia. 4(2):43-49.

A transverse image through the lower A longitudinal image through the right A longitudinal image through the right left aspect of the left scrotal sac, scrotal sac, with the testis (star) superior scrotal sac, with the testis (star) displaced demonstrating a varicocele (arrowheads) to a focal high reflective area in the sac, superiorly by a mixed reflective, partly and a well circumscribed mixed reflective between the two layers of the tunica calcified lesion identified as a lesion; a haemangioma of the para- vaginalis and albuginea (arrow), pseudotumour. testicular space. demonstrating posterior acoustic shadowing; a scrotal pearl.

Scrotal Ultrasound Intra-testicular Pathology

Malignant Lesions Benign lesions

Germ cell tumours Epidermoid cyst Segmental Infarction Precursor lesions Abscess formation Intratubular germ cell neoplasia cyst Tumours of one histological type Rete testis Seminoma Simple cyst Embryonal carcinoma Fibrosis and scarring Post-biopsy Yolk sac tumour Sarcoidosis Choriocarcinoma Adenomatoid tumour Teratoma Lipoma Scrotal Ultrasound Tumours of more than one histological type Granuloma Polyorchidism Tumours with both sex cord and stromal Ectopic spleen cells and germ cells Haematoma INTRA-TESTICULAR PATHOLOGY Gonadoblastoma Fracture Lymphoid and hematopoietic tumours Sex cord and stromal tumours Lymphoma tumour Leukaemia tumour Metastasis Granulosa cell tumour Fibroma-thecoma

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Scrotal Ultrasound Scrotal Ultrasound Intra-testicular Pathology Intra-testicular Pathology Testicular Tumours Seminoma • Incidence and Aetiology – Affects younger men – Commonest malignancy in men aged 20-40 years Segmental Infarction Epidermoid Cyst – 1400 new cases per year in UK Mixed – 1% of all cancers in men Germ Cell • Incidence varies from country to country Teratoma – Denmark 6 per 100,000 men Adenocarcinoma • Seminoma Incidence steadily increasing Teratoma Leydig Cell tumour – 1940; incidence in USA 2.88 per 100,000 men Lymphoma – 1990; incidence in USA 4.50 per 100,000 men

Acute Myeloid Leukaemia • Increased in; – Undescended testis (2-4%) – Contralateral cancer (5%) Embyronal Cell Carcinoma Lymphoma – Extra-gonadal germ cell cancer (40%) – Cases of intersex – x 6-10 in siblings (mutation chromosome Xq27)

Scrotal Ultrasound Scrotal Ultrasound Intra-testicular Pathology Intra-testicular Pathology

Intra-testicular Haematoma

Seminoma • The ultrasound appearance of an intra-testicular haematoma changes 3 x 4 mm with time. • Acutely the haematoma appears as a patchy area of increased reflectivity. • The haematoma does not demonstrate vascular flow. Embryonal cell carcinoma • The most important differential diagnosis is malignancy and therefore an accurate history, lack of vascularity and tumour markers are important. • If suspected sequential scans are advocated to show the haematoma decreasing in size.

The assumption is that intra-lesion

vascularity is a hallmark of malignancy. Purushothaman H, Sellars MEK, Clarke JL, Sidhu PS. Intra-testicular haematoma: Differentiation from tumour on clinical history and ultrasound appearances in two cases. British Journal of Radiology 2007;80:e184-e187

Scrotal Ultrasound Scrotal Ultrasound Intra-testicular Pathology Intra-testicular Pathology Epidermoid Cysts Intra-testicular Abscess

• Epidermoid cysts are the commonest benign tumours arising from the testis though accounting for only 1-2% of all resected testicular masses. • Intratesticular abscesses are unusual and are usually associated • The ultrasound features varies with the degree of maturation, compactness and with epidiymo-orchitis but may also arise secondary to mumps, quantity of the keratin within the cyst trauma or infarction. • The ultrasound appearances are of a complex hypoechoic Type 1: classic ‘onion-ring’ appearance. intratesticular lesion with irregular shaggy borders. Type 2: densely calcified mass with no cyst seen. Type 3: cyst with a rim and either peripheral or central calcification. Type 4: mixed pattern, heterogeneous and poorly defined.

Dogra VS, Gottlieb RH, Rubens DJ, Oka M, Di Sant Agnese AP. Testicular epidermoid cysts: sonographic features with histopathological correlation. J Clin Ultrasound 2001; 29:192-196.

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Scrotal Ultrasound Scrotal Ultrasound Intra-testicular Pathology Intra-testicular Pathology

Segmental Testicular Infarction Neoplastic Lesions

• The inability to differentiate this from testicular malignancy has resulted in orchidectomy. • Clinically segmental infarction presents with pain. • Segmental infarction appears on ultrasound as a low reflective area which may be wedge shaped. • There is no posterior acoustic enhancement and focal expansion of the testis has been described. • Crucially there is no Doppler flow within an area of infarction whereas a malignant lesion usually demonstrate increased flow.

Bilagi P, Sriprasad S, Clarke JL, Sellars ME, Muir GH, Sidhu PS. Clinical and ultrasound features of segmental testicular infarction: Six-year experience from a single centre. European Radiology 2007;17:2810-2818.

Scrotal Ultrasound Global Abnormalities Scrotal Content Torsion Spermatic Cord Torsion • Age range 12 - 18 years A. Extra-vaginal Torsion • 1 in 4000 males under 15 years Neonatal Spermatic Cord Torsion Tumeh SS, Benson CV, Richie JP. Acute diseases of the scrotum. Seminars in Ultrasound, CT, and MRI 1991;2:115-130. B. Intra-vaginal Torsion • Most commonly as puberty approaches when Classical Spermatic Cord Torsion testicular volume increases by x5 C. Torsion of an Appendix Appendix Testis Appendix Epididymis Viability < 4 hours : 95% < 8 hours : 90% Predisposing factors < 12 hours : 80% < 24 hours : 40% Scrotal Ultrasound Narrow mesenteric attachment, 80 % bilateral (‘bell-clapper’ > 24 hours : 10% deformity) Sheldon CA. Symposium on pediatric surgery. 1. Undescended testes and Bellinger MF. The blind-ending vas: the fate of the contralateral testis. Journal of testicular torsion. Surgi Clini North Am 1985;65:1303-1329. GLOBAL ABNORMALITIES Urology 1985;133:644-645. Other factors as incidence of torsion is 0.025% compared with a post mortem incidence of 12% of ‘bell-clapper’ deformity Caesar RE, Kaplan GW. Incidence of bell-clapper deformity in an autopsy series. Pediatric Urology 1994;44:114-116.

Whirlpool sign Absent vascularity

Scrotal Ultrasound Scrotal Ultrasound Global Abnormalities Global Abnormalities • Acute Torsion Scrotal calcification Testicular Microlithiasis – Low reflective • Defined as the presence of multiple (>5) tiny (2- Intratesticular Extratesticular – Echogenic tunica/mediastinum 3mm) echogenic foci throughout the testis – Small amount of fluid Malignant Benign Chronic inflamation • Usually bilateral – Enlarged epididymis/scrotal skin oedema • Calcification in degenerating seminiferous tubules Phleboliths – Twisted spermatic cord Calcification in tumours Testicular Microlithiasis (TM) • Classification into Limited (<5) and Classical (>5) Scrotal pearl • Chronic/missed Torsion Non TM benign calcification – Bennett HF, Middleton WD, Bullock AD, Teefey SA. Testicular microlithiasis: US follow-up. Radiology 2001;218:359-363 – High reflective Epididymal calcification Granuloma – Heterogeneous with haemorrhage – Low reflective/small Infarct Haematoma

Is Testicular Microlithiasis Associated with Malignancy? • Asymptomatic testis serves as baseline for colour flow • Testicular cancer arises from intra-tubular germ cell neoplasia • There is no single clinical feature that can (ITGCN) on the basal membrane of the seminiferous tubules – symmetry of flow < 13 years; 58% Ingram S, Hollman AS. Colour Doppler sonography of the paediatric testis reliably distinguish torsion from other causes • TM in any testis is associated with the presence of ITGNC Clin Radiol 1994;49:266-267 of testicular pain • The assumption is that patients with TM have ITGNC as a – Testicular volume > 1ml; 84% precursor to the development of a tumour Atkinson GO, Patrick LE, Ball TI et al. The normal and abnormal scrotum in children: evaluation with color Doppler sonography AJR • CDUS can reliably image acute epididymo- • Very few case reports of testicular tumour developing in patients 1992;158:613-617 with TM, particularly in patients without other risk factors orchitis but there is no imaging ‘gold-standard’ for testicular torsion • Should we follow-up men with non-TM calcification? • Should we advocate self-examination only?

Sidhu PS. Clinical and imaging features of testicular torsion: role of ultrasound. Clinical Radiology 1999;54:343-352. Patel KV, Navaratne S, Bartlett E, Clarke JL, Muir GH, Sellars ME, Sidhu PS. Testicular Microlithiasis: Is Sonographic Surveillance Necessary? Single Centre 14 Year Experience in 442 Patients with Testicular Microlithiasis. Ultraschall in der Medizine 2016;37:68-73

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Scrotal Ultrasound Global Abnormalities A : No risk factors for testicular cancer Self testicular examination Patient TC 28 years old Annual physical examination by GP Follow-up as needed by Urologist • 1997 – Bilateral classical TM • 2002 – Multi-centric left seminoma with B : Risk factors for testicular cancer surrounding intra-tubular germ cell Self testicular examination neoplasia • 2006 Annual physical examination by Urologist – 4 x 5 mm right seminoma with Annual ultrasound surrounding intra-tubular germ cell neoplasia 2002

Gilbert S, Nuttall MC, Sidhu PS, Ravi R. Metachronous Testicular Tumours Developing Five and Nine Years Following the Diagnosis of Testicular Microlithiasis. Journal of Ultrasound in Medicine 2007;26:981-984. Scrotal Ultrasound

Risk factors for Germ Cell Tumour Age Cryptorchidism (risk x4 - 8) NEW TECHNIQUES Contralateral tumour (risk x12.4 - 27.5) Family history – first degree relative (risk x4 - 8) 2006 Risk for Leydig cell hyperplasia Kleinfelter's syndrome Infertility

Rashid HH, Cos LR, Weinberg E et al. Testicular microlithiasis: a review and its association with testicular cancer. Uro Oncol 2004;22:285-289

Scrotal Ultrasound Scrotal Ultrasound New Techniques New Techniques Contrast Enhanced Ultrasound (CEUS)

Truly intravascular agent, able to depict Tissue Elastography vascularity to very low levels, good to distinguish vascularised from non–vascularised tissue Able to depict the ‘stiffness’ of the lesion with the presumption that a ‘hard’ lesion is more likely malignant

Seminoma

Scrotal Ultrasound Scrotal Ultrasound New Techniques New Techniques

Leydig Cell Tumour Seminoma

Heterogenous More homogenous Highly vascular on CDUS Less vascular on CDUS Haematoma Epidermoid Cyst Rapid and longer lasting enhancement on CEUS Rapid and shorter lasting enhancement on CEUS Strain ratio 1.56 Strain ratio 43.72

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Scrotal Ultrasound Scrotal Ultrasound New Techniques New Techniques

(a) (b)

Scrotal Ultrasound New Techniques

Scrotal Ultrasound ROLE OF MRI

Incidental Indeterminate Testicular Lesion Thank you Role of MR Imaging Scrotal MRI is a problem-solving tool

▪ Most testicular tumours are of low signal intensity on T2-WIs, iso-intense to testicular parenchyma on T1-WIs, and demonstrate enhancement with contrast. Non-seminomatous germ cell tumours are typically heterogeneous, while teratomas may show cystic or fatty component.

▪ Leydig cell is of low signal intensity on T2-WIs with mild enhancement after contrast administration.

▪ Different types of time-intensity curves have been defined on dynamic contrast-enhanced MRI. ▪ 44 testicular lesions, including 21 sex cord stromal tumours, reports well-defined margins, rapid and marked wash-in followed by slow and late wash-out should orient to the diagnostics of Leydig cell tumours.

▪ Benign and malignant lesions in the testes cannot accurately be distinguished by ADC values as significant variations and overlap exist between different tumour subtypes; tumour size and degree of necrosis can also influence the ADC values.

Manganaro L, Vinci V, Pozza C, et al. (2015) A prospective study on contrast-enhanced magnetic resonance Leydig Cell Hyperplasia imaging of testicular lesions: distinctive features of Leydig cell tumours. Eur Radiol 2015;25:3586-95 Seminoma Thank You

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