Epididymitis is the commonest intra-scrotal inflammation.
Epididymitis accounts for 75% to 80% of acute inflammatory disease
of the scrotum. Swelling and sonographic epididymal abnormalities,
skin thickening, and hydrocele are more suggestive of an infectious
process than of tumor. Patients have pain for at least 2 days
and may have a discharge.
Epididymitis may be acute or chronic and related to infection
The most frequent cause of epididymitis is a bacterial infection
(nonspecific germ : frequently the chlamydia or specific : gonorrhea
or syphilis). This infection is usually from an urinary tract
Sonographic appearances are variable depending upon the stage
and severity of the disease. The epididymus is usually enlarged
and hypoechoic, but it may be intensely echogenic. Colour Doppler
imaging shows hypervascularity within the epididymus.
In uncomplicated cases of epididymitis the testicle is usually
not involved though there may be hypoechoic foci in the testicular
parenchyme adjacent to the epididymus. With advanced epididymitis,
small abscesses are occasionally seen as complex hypoechoic collections
in the epididymis.
In chronic epididymitis, the epididymus is thickened and focally
echogenic and may have calcifications.
In tuberculous epididymitis, the epididymus may become heterogeneous
and hypoechoic associated with concomitant hypoechoic lesions
in the testis and a discharging sinus. The testis may become stony
hard associated with extra-testicular calcification.
Orchitis usually occurs in conjunction with epididymitis. Isolated
orchitis is less common and generally is viral. Testicular enlargement,
decreased echogenicity, and hypervascularity are ail typical findings
As with epididymitis, hypervascularity may be the only abnormal
finding, so color Doppler analysis is more sensitive in the diagnosis
of orchitis than is gray-scale sonography alone.
Torsed appendix testis.
Benign solid tumors of the epididymus.
Fibrous pseudo-tumor of the epididymus.
Lipoma or fibrolipoma of the spermatic cord.
Papillary cystadenoma of the epididymus.
Paratesticular rhabdomyosarcoma, leiomyosarcoma and other extratesticular
Metastatic tumor of the tunica vaginalis.