The Acute Scrotum: Sonographic Findings 가천의대길병원방사선과 양달모 Gachon Medical School
Introduction Many diseases presenting as acute scrotal pain DDx is important for determining the appropriate treatment US with high-frequency transducer (7-10 MHz) is the imaging modality of choice for evaluating patients with acute scrotal pain Color and power Doppler US demonstrate testicular perfusion and aid in reaching a specific diagnosis
Anatomy of scrotum US appearances of acute scrotal disease
Anatomy Testis 5 x 3 x 2 cm Tunica vaginalis; parietal layer, visceral layer Tunica albuginea seminiferous tubules tubulus rectus rete testis efferent duct epididymal duct Epididymis Head (7~8 mm), body, tail (1~2 mm) Vas deferens
US Anatomy US of testis homogeneous, medium-level echo texture mediastinum testis US of Epididymis isoechoic to the testis
Vascular Anatomy Artery Testicular artery (br of the abdominal aorta) Deferential artery (br of the superior vesical a) Cremasteric artery (br of inferior epigastric a) Vein Pampiniform plexus testicular vein IVC (Rt), left renal vein (Lt)
Acute Scrotum Epididymitis, Epididymo-orchitis Testicular torsion Appendiceal Torsion Testicular Trauma Varicocele
Acute epididymo-orchitis m/c cause of acute scrotum in adolescent boys and adults younger than 35 yrs: Chlamydia trachomatis, Neissseria gonorrhea over 35 years: E coli, Proteus mirabilis positive Prehn s sign first affect tail, spreads to the body and head
Acute epididymitis Gray scale US enlarged, hypoechoic hydrocele, pyocele, scrotal wall thickening
Acute epididymitis Color Doppler US increased number and concentration of identifiable vessels
Acute epididymitis: focal involvement
Acute epididymitis Involvement of vas deferens
Acute epididymitis: pitfall
Epididymal Abscess
Acute epididymo-orchitis Gray scale US testicular enlargement and inhomogeneous echotexture
Acute epididymo-orchitis Color Doppler US hyperemia in the testis Spectral Doppler RI of less than 0.5 (50% )
86 Y Testicular abscess
Testicular ischemia secondary to Epididymo-orchitis compromise of testicular blood flow from a/w edema and swelling 52 Y
Focal orchitis US poorly defined, hypoechoic, increased blood flow difficult to differentiate from testicular tumor tumor marker, follow-up sonography 45 Y
Mumps orchitis It occurs15-30% of men with mumps usually occur within several days of having parotid infection 15Y
Testicular torsion occurs most commonly from 12 to 18 years of age sudden onset of pain followed by nausea, vomiting negative Prehn s sign venous engorgement edema, hemorrhage arterial compromise ischemia The testicular salvage rate depends on the degree of torsion and the duration of ischemia within 6hrs : 100% 6-12hrs : 70% 12-24 hrs : 20%
Testicular torsion Intravaginal torsion : Bell-Clapper deformity Extravaginal torsion
Testicular torsion Gray scale US non-specific vary with duration and degree of rotation
Testicular torsion Color Doppler US absence of intratesticular flow sensitivity; 86%, specificity; 100%, accuracy; 86% 16 Y
Testicular detorsion 16 Y Courtesy of Park SJ, Soonchunhyang Univ
Appendages in scrotum Appendix testis Appendix epididymis Paradidymis (Organ of the Giraldes) Vas aberrans of Haller
US of Appendages Appendix testis attached to upper pole of testis in the groove between the testis and the epididymis ovoid structure 5 mm in length isoechoic to the testis and may be cystic Appendix epididymis attached to head of the epididymis
Appendiceal Torsion The most common cause of acute painful scrotum in the child (35~67%) occur aged 7 to 14 years Appendix testis: 91-95% Physical exam a small, firm nodule that is palpable on the superior aspect of testis a bluish discoloration through the overlying skin blue dot sign self-limiting process, the symptoms will usually subside within a week
Appendiceal Torsion Gray scale US a circular mass that variable echogenicity adjacent to the testis or epididymis hydrocele, scrotal wall thickening 10 Y
Appendiceal Torsion Color Doppler US no blood flow within the appendix increased peripheral blood flow around the torsed appendages 10 Y
Appendiceal Torsion A size of 5 mm or larger, a spherical shape, and increased periappendiceal blood flow are indicative of a torsed appendix testis J Ultrasound Med 2005 13 Y
Testicular trauma result from athletic injury, a motor vehicle accident, straddle injury, penetrating gunshot trauma Contusion, hematoma, rupture of testis
Testicular rupture US disruption of the tunica albuginea direct visualization of a fracture line. large hematocele 45 Y
16 Y Testicular rupture
Varicocele Idiopathic or primary varicocele abnormal dilatation of the veins of the pampiniform plexus usually caused by incompetent valves in the internal spermatic veins Secondary varicocele hydronephrosis, cirrhosis, abdominal neoplasm US - multiple,serpigeneous, tubular structures of varying sized larger than 2 mm in diameter - upright position or Valsalva s maneuver
Varicocele
Summary Gray scale and color Doppler US is helpful for differential diagnosis of acute scrotal pain Epididymo-orchitis vs Testicular torsion Torsion of appendix testis, varicocele, testicular rupture Focal orchitis vs Testicular tumor