Sonography of acute scrotal abnormalities

Accurate diagnosis in patients with acute scrotal abnormalities remains a challenge to both radiologists and clinicians. Sonography using either small parts scanners or conventional equipment available in almost all departments will continue to play a larger role in aiding the clinical assessment of these patients. As a rapid, noninvasive imagining technique, sonography can reliably answer important clinical questions and guide prompt, early surgical or medical therapy.     

Asymptomatic scrotal masses in children

The ultrasound scans of 16 boys with asymptomatic scrotal masses were retrospectively studied. Ultrasound localized seven of the masses as primary testicular lesions and nine as extratesticular lesions, six of which were hydroceles. Ultrasonography also characterized the scrotal masses as predominantly cystic or solid. Ultrasound could not differentiate benign from malignant disease when a solid mass was found. When a hydrocele was identified, ultrasound was able to image the underlying testis and accurately evaluate it for primary disease. These ultrasound observations can help the surgeon decide when to explore the scrotum and whether to approach the testes via an inguinal or scrotal incision. Conversely, ultrasonographic confirmation of a normal testis may prevent needless surgery and the removal of a normal testis.     

Sonography of neck masses in children

The sonograms and medical records of 49 patients were reviewed to determine if there is a characteristic sonographic appearance for certain neck masses. Neck masses included: inflammatory masses (12), noninflammatory masses (23), and thyroid masses (14). Four entities including thyroglossal duct cyst, fibromatosis colli, cystic hygroma, and multiple lymphadenopathy showed characteristic sonographic appearance. Thyroglossal duct cysts were seen as midline or slightly off midline cystic masses. A sinus tract extending superiorly was nicely demonstrated in one patient. The mass in fibromatosis colli (neonatal torticollis) appeared as a well defined mass clearly within the sternocleidomastoid muscle, uniformly echogenic, but less echogenic than the normal surrounding muscle, without good through-transmission. A cystic or primarily cystic mass with linear septations was the characteristic finding of the cystic hygroma. Multiple lymphadenopathy demonstrated multiple discrete, oval, relatively hypoechoic masses along the cervical lymphatic chain. The sonographic appearance of inflammatory masses was variable, being either inhomogeneously echogenic or of mixed echogenicity. Hemangiomas were either echogenic with cystic vascular spaces or linear septations or relatively homogeneously echogenic. Intrinsic thyroid masses could be distinguished from extrinsic masses in most cases. The demonstration of calcification in a mass was useful in narrowing the differential diagnosis. Although it is not a specific finding, the presence of calcification highly suggests a neoplastic lesion, particularly neuroblastoma or teratoma. Not only can the location, extent, and internal characteristics of a mass be determined, but in certain entities, the sonographic appearance is characteristic and an accurate diagnosis can be made.     

Sonography in benign and malignant renal masses

Ultrasonography and CT have allowed improved detection of renal mass lesions. Though ultrasonography is less sensitive in the characterization of the renal mass lesions, it is often the first imaging modality for evacuation of the kidneys. This article gives an overview of the benign and malignant renal mass lesions and the role of ultrasonography in their characterization.     

Differential diagnosis of scrotal masses by ultrasound

Ultrasound is the mainstay for imaging of the scrotum. It is used primarily for determining the location and nature of palpable lesions and to demonstrate nonpalpable lesions. Scrotal US is characterized by high sensitivity in the detection of intrascrotal abnormalities and is a very good mode for differentiating testicular from paratesticular lesions. However, scrotal US is limited in determining whether a focal testicular lesion is benign or malignant. The limitations of gray-scale US in the assessment of an acute scrotum and in particular of testicular torsion have now been overcome by color-coded duplex sonography and power Doppler.     

Sonography of the adrenal glands: normal glands and small masses

To evaluate sonographic imaging of the normal adrenal glands, anterior transverse and longitudinal scans were made on 200 patients who had no evidence of adrenal disease. In 78 additional patients who were suspected of having adrenal masses, anterior and posterior transverse and longitudinal scanning and longitudinal oblique scanning were done. Anterior transverse scanning proved to be the best single method of scanning the adrenal gland and small adrenal masses. The normal adrenal gland which is 3-6 mm thick and adrenal masses as small as 1.3 cm can be delineated. Although the frequency of visualizing normal adrenal glands (78.5% on the right and 44% on the left) with sonography is not as high as with CT, masses are more readily detected than the normal glands. The accuracy for detecting adrenal masses is very high, with a false-negative rate of only 3%. Sonography can be a useful screening test for many patients who are suspected of having adrenal masses. However, for obese patients the image is degraded and a higher false-positive rate (3.5%) is obtained. CT provides better resolution for such patients.     

Sonography of small renal masses with indeterminant density characteristics on computed tomography

Nine small renal masses with attenuation coefficients greater than 20 HU on computed tomography (CT) were termed indeterminate for cyst or renal cell carcinoma. Correlative sonography identified the fluid-filled internal architecture in four of five cysts and correctly characterized as solid four small renal cell carcinomas. The sonogram was particularly valuable in assessing masses that were indeterminate on CT when enhancement was equivocal or when intravenous contrast could not be administered. We conclude that sonography is extremely useful as a noninvasive procedure in evaluating the occasional small renal mass with CT number greater than 20 HU.     

Sonography of small renal masses with indeterminant density characteristics on computed tomography

Nine small renal masses with attenuation coefficients greater than 20 HU on computed tomography (CT) were termed indeterminate for cyst or renal cell carcinoma. Correlative sonography identified the fluid-filled internal architecture in four of five cysts and correctly characterized as solid four small renal cell carcinomas. The sonogram was particularly valuable in assessing masses that were indeterminate on CT when enhancement was equivocal or when intravenous contrast could not be administered. We conclude that sonography is extremely useful as a noninvasive procedure in evaluating the occasional small renal mass with CT number greater than 20 HU.     

From the archives of the AFIP: extratesticular scrotal masses: radiologic-pathologic correlation.

The extratesticular scrotal contents consist of the epididymis, spermatic cord, and fascia derived from the embryologic descent of the testis through the abdominal wall. As opposed to intratesticular masses, most extratesticular masses are benign. Cystic masses (including hydroceles, epididymal cysts, and varicoceles) are easily diagnosed with ultrasonography (US) and are benign. Epididymitis is a common extratesticular lesion as well as the most frequent cause of an acute scrotum. It may be either acute or chronic and can be potentially complicated by epididymo-orchitis or scrotal abscess. Findings include epididymal enlargement, skin thickening, hydroceles, and hyperemia. The epididymis can also be affected by sarcoidosis, a noninfectious granulomatous disorder. The most common extratesticular neoplasms are lipomas (most often arising from the spermatic cord) and adenomatoid tumors (most often found in the epididymis). Despite their relative rarity, malignant neoplasms do occur and include rhabdomyosarcoma, liposarcoma, leiomyosarcoma, malignant fibrous histiocytoma, mesothelioma, and lymphoma. These tumors are often large at the time of presentation. The US findings of solid masses are often nonspecific. Magnetic resonance imaging can be very helpful in the evaluation of some of these disorders, allowing for a more specific diagnosis in cases of lipoma, fibrous pseudotumor, and polyorchidism. Copyright RSNA, 2003.     

Unusual scrotal mass and review of scrotal imaging

Asymptomatic painless testicular swellings are not uncommon. The differential diagnosis of scrotal mass includes cysts, lipomas, hydrocele, varicocele, benign and malignant testicular masses. Prompt clinical examination followed by appropriate imaging is the key to early diagnosis and appropriate management. Our case is that of a self-neglected, long standing partially ruptured benign epidermal inclusion cyst masquerading as a massive painless scrotal mass. Magnetic resonance imaging not only displays the size and margins of these lesions, but also shows characteristic internal features that may suggest the preoperative diagnosis. We report a case of unusually large cystic scrotal extratesticular epidermal inclusion cyst, illustrate the imaging characteristics and discuss the differential diagnoses.