Ultrasound Assessment of Scrotal Emergencies

Summarized by: Akshay Wadera, M.D.

Reviewed by: Zonia Ghumman, M.D.

Original publication details

Authors: Christopher R. McAdams & Andrew J. Del Gaizo

DOI: https://doi.org/10.1007/s10140-018-1606-y

Reference: McAdams, C. R., & Del Gaizo, A. J. (2018). The utility of scrotal ultrasonography in the emergent setting: beyond epididymitis versus torsion. Emergency Radiology, 25(4), 341-348.

Background

Physical examination and sonography are cost-effective ways of assessing scrotal and periscrotal emergencies

Testicular torsion and epididymo-orchitis are two of the most common diagnoses

Technique

Position

Supine position with penis positioned superiorly/superolaterally and proper draping technique

Transducer

Linear high frequency (7.5 - 15 MHz). Curvilinear lower frequency in cases with significant scrotal edema. 

Views:

Saddle view, sagittal and transverse planes

Testicular Torsion

Typical presentation

Acute scrotal pain

Imaging: 

Can be relatively hypoechoic, homogenous (early) and heterogeneous (late after 24 hours) suggesting necrosis

Decreased or absent blood flow

Epididymitis-Orchitis

Typical presentation

Acute scrotal pain

Imaging: 

Relatively hypoechoic in orchitis 

Variable echogenicity in epididymitis 

Increased blood flow/hyperemia

Torsed Testicular/Epididymal Appendage

Typical presentation

Unilateral focal acute scrotal pain in prepubertal males. No clinical significance between torsed testicular appendage or torsed epididymal appendage

Imaging: 

Ovoid extratesticular/extra-epididymal mass 

Variable echogenicity

Peripheral vascularity with no internal blood flow

Associated findings: ipsilateral scrotal skin thickening and reactive hydrocele

Intratesticular or Epididymal Abscess

Typical presentation

Untreated epididymitis-orchitis or retrograde spread lower urinary tract bacterial infections. May progress to pressure necrosis if left untreated

Imaging: 

 Round intratesticular/intraepidydmal collection 

Variable echogenicity

Peripheral vascularity with no internal blood flow

Hematoma

Typical presentation

Acute scrotal pain, usually traumatic.

Imaging: 

Hyperechoic ovoid collection of varying size

Variable echogenicity

No internal blood flow or peripheral vascularity 

Sonographic follow-up to resolution recommended due to high risk of infection/necrosis and exclusion of incidental tumor

Testicular Fracture/Rupture

Typical presentation

Acute scrotal pain after blunt trauma. Delayed surgical management can lead to increased risk of infection and necrosis 

Imaging: 

 Linear hypoechoic abnormality extending across parenchyma

Rupture defined by visible discontinuity/irregularity of tunica albuginea

Associated findings: Can have extrusion of testicular parenchyma through defect

Penetrating Trauma

Typical presentation

Most common source is gunshot wounds

Imaging: 

 Hypoechoic tracts 

Associated findings: may have secondary testicular parenchymal injury, vascular compromise, and spermatic cord transection

Intratesticular or Extratesticular Varicocele

Typical presentation

Vague discomfort or palpable mass, more common on the left

Imaging: 

 Hypoechoic/anechoic tubular structures inside testicular parenchyma close to mediastinum testes or extratesticular tubular structures measuring over than 2mm.

Internal blood flow with venous spectral waveforms that enlarge with Valsalva or standing maneuvers

Simple Hydrocele

Typical presentation

Idiopathic or reactive to infection, trauma, torsion, or neoplasm

Imaging: 

Uniform anechoic extratesticular collection with no blood flow

Complex Hydrocele

Typical presentation

Traumatic or infectious presentations are most common. Large collections can exert mass effect which predispose patent to vascular compromise/infarct

Imaging: 

Extratesticular collection with mobile internal echoes. 

Foci of dirty shadowing may represent gas in cases of pyocele 

Variable echogenicity

No internal blood flow. Peripheral vascularity in cases of abscess

Inguinal Hernia

Typical presentation

Acute pain/swelling in cases of incarceration that may enlarge with Valsalva 

Imaging: 

Hyperechoic fat or bowel signature with foci of dirty shadowing that may represent gas in bowel

Variable blood flow pattern on Doppler depending on contents

Fat demonstrates no blood flow in normal circumstances  Decreased/absent blood flow in cases of incarceration

Funiculitis

Typical presentation

Painful unilateral scrotal pain 

Imaging: 

Edematous enlargement of ipsilateral spermatic cord

Heterogeneous echotexture

Increased blood flow

Associated Findings: engorged para-funicular vessels that enlarge with Valsalva maneuver

Funicular Collections

Pathology

Encysted hydroceles result from irregular closure of processus vaginalis and does not communicate with the peritoneum or scrotum 

Imaging: 

Beaded/loculated fluid collections accumulate along spermatic cord

Penile Trauma/Fracture

Typical presentation

Blunt trauma when the penis is erect because of physiologic stretching/thinning of tunica albuginea 

Imaging: 

Discontinuity of thin echogenic tunica albuginea band 

Associated Findings: possible hematoma and herniation of corpora

Fournier Gangrene

Typical presentation

Pain and swelling is an often common first presentation making sonography often the initial imaging study. CT is preferred for potential perineal infection.

Imaging: 

Multiple echogenic foci with dirty shadowing representing gas within the scrotal wall 

Increased blood flow

Cellulitis

Typical presentation

Erythema swelling and warmth of the scrotal skin surface

Imaging: 

Subcutaneous reticulation with heterogeneous/hypoechoic scrotal wall thickening 

Increased blood flow

Associated Findings: Possible localized superficial fluid collections

3rd Spacing

Typical presentation

Generalized ascites or volume overload states due to systemic process such as congestive heart failure or sepsis

Imaging: 

Diffuse symmetric scrotal heterogeneous/hypoechoic skin thickening due to edema

Variable blood flow

Referred Pain

Typical presentation

Colicky pain in a patient with history of urolithiasis and no periscrotal cause

Imaging: 

Echogenic focus with shadowing most commonly in the lower urinary tract 


Citation


McAdams, C. R., & Del Gaizo, A. J. (2018). The utility of scrotal ultrasonography in the emergent setting: beyond epididymitis versus torsion. Emergency Radiology, 25(4), 341-348.