Pitfalls and Practical Challenges in Imaging of the Pediatric Scrotum.

ABSTRACT: Ultrasound is the modality of choice for evaluation of the pediatric scrotum, as it provides excellent image quality without the use of radiation, need for sedation/anesthesia, or use of contrast material and can be used for serial examination. Ultrasound of the scrotum has proven to be useful for assessment of a wide gamut of congenital, infectious, inflammatory, endocrine, neoplastic, and traumatic abnormalities in pediatric patients of all ages from the tiniest premature infant to a fully grown young adult. This review article presents a varied spectrum of conditions that may affect the pediatric scrotum, what the radiologist needs to know to meet the challenge of limiting the differential diagnosis, and how to avoid pitfalls when imaging the scrotum.

US of Pediatric Superficial Masses of the Head and Neck.

Superficial palpable masses of the head and neck are common in the pediatric population, with the vast majority of the lesions ultimately proven to be benign. Duplex ultrasonography (US) has emerged as the first-line imaging modality for the evaluation of superficial pediatric masses. Without utilizing radiation, iodinated contrast material, or sedation and/or anesthesia, US provides a means for quick and cost-effective acquisition of information, including the location, size, shape, internal content, and vascularity of the mass. In this review, the US findings are described for a variety of common and uncommon pediatric head and neck masses diagnosed in our practice. Specifically, the entities covered include neonatal scalp hematoma, craniosynostosis, dermoid and epidermoid cysts, Langerhans cell histiocytosis, lymph nodes and their complications, fibromatosis colli, thyroglossal duct cyst, branchial cleft cyst, cervical thymus, congenital goiter, thyroid papillary carcinoma, parathyroid adenoma, hemangioma, lymphangioma, jugular vein phlebectasia, Lemierre syndrome, acute parotitis and parotid abscess, leukemia and/or lymphoma, neurogenic tumor, and rhabdomyosarcoma. Ultimately, in situations in which the head or neck mass is too large, deep, or hyperechoic to be fully assessed within the US field of view, or if malignancy or a high-flow vascular lesion is suspected, then further evaluation with cross-sectional imaging is warranted. Online supplemental material is available for this article. ©RSNA, 2018.

Anatomy and pathology of the canal of Nuck.

The canal of Nuck is the female equivalent of the processus vaginalis in the male but is less well known than its male counterpart. It is a rare entity not commonly encountered by radiologists, particularly in the adult population. Knowledge of the embryology and anatomy of the canal of Nuck is essential for identification of the various pathologic conditions that may occur in this location. Moreover, radiologists should be familiar with this entity to compose an appropriate and thorough differential diagnosis of a labial mass/swelling. In this review, we discuss both the anatomy and the more common pathology that can be encountered within it.

Sonography of pediatric superficial lumps and bumps: illustrative examples from head to toe.

Superficial lumps and bumps are extremely common in children, and the vast majority ultimately prove to be benign. Duplex/color Doppler ultrasound (US) has emerged as the first-line imaging modality for the evaluation of these superficial pediatric masses because it provides a means for rapid acquisition of information including size, shape, location, internal content and vascularity. More important, it does so without utilizing radiation, iodinated contrast material or sedation/anesthesia. In this review, we present the sonographic findings of a variety of cases ranging from head to toe that are either uncommonly seen or were diagnosed in an atypical fashion (i.e. ultrasound). In situations where the lesion is too deep, hyperechoic or large to be fully assessed within the field of view or if malignancy is suspected, then additional cross-sectional imaging is warranted for further evaluation.

Thyroid Imaging in Infants.

Congenital hypothyroidism is the most common preventable cause of mental retardation. It is important to know the cause of each patient's thyroid dysfunction to foresee the course of therapy and outcomes. Imaging methods, such as ultrasound and thyroid scan, help determine the anatomy and function of the thyroid gland. Although thyroid scan is considered superior in detecting ectopic thyroid tissue, ultrasound is able to detect the presence of thyroid tissue not otherwise visualized in 15% of patients.

Pelvic ultrasonography in the evaluation of central precocious puberty: comparison with leuprolide stimulation test.

OBJECTIVE: To compare the ovarian and uterine structure demonstrated sonographically with baseline and leuprolide-stimulated luteinizing hormone (LH) and estradiol values in females with suspected precocious puberty. STUDY DESIGN: Retrospective chart review. Fifty females (age 3.1 to 9.5 years) underwent stimulation testing with leuprolide (20 µg/kg) and pelvic ultrasonography. Subjects were grouped as (1) prepubertal (baseline and stimulated LH and estradiol in prepubertal range); (2) early pubertal (baseline LH and estradiol in prepubertal range but stimulated LH or estradiol in pubertal range); and (3) pubertal (baseline and stimulated LH or estradiol in pubertal range). Sonographic data were compared with baseline and leuprolide-stimulated LH and estradiol. RESULTS: Baseline and stimulated LH and stimulated estradiol significantly correlated with ovarian and uterine volumes. Ovarian and uterine volumes were significantly higher in females in the pubertal group than in females in the prepubertal group. No significant differences were noted in the ovarian or uterine dimensions between the prepubertal and early pubertal groups. There was significant overlap in ovarian and uterine volumes among females in all three groups. CONCLUSION: Contrary to leuprolide stimulation, pelvic ultrasonography alone cannot distinguish between prepubertal females and those in the early stages of puberty.

Sonography of the pelvis in patients with primary amenorrhea.

Duplex/color Doppler sonography (US) is the imaging modality of choice for the evaluation of patients with primary amenorrhea. Careful correlation with clinical history, physical examination and laboratory findings significantly narrows the diagnostic possibilities thus allowing for a more precise diagnosis. This article discusses the wide gamut of etiologies of primary amenorrhea, the US appearance of pathologic processes that result in primary amenorrhea, and helps the reader understand when additional higher tech imaging is indicated.

Duodenal and rectal hematomas complicating endoscopic biopsy: use of sonography in pediatrics.

OBJECTIVE: Intramural duodenal hematomas (IDHs) after nontherapeutic endoscopic biopsy are rare. Rectal hematomas (RHs) have not been reported previously. A review of the literature revealed 18 cases of IDHs. METHODS: We reviewed 3 cases that occurred within a 4-month period at our institution. RESULTS: We report a series of 3 cases occurring within a 4-month period. In addition, we report a concurrent RH in 1 of these cases. After becoming symptomatic, 2 of these patients had a diagnosis by computed tomography, the third by sonography. All patients had conservative management and were followed with sonography. CONCLUSIONS: Sonography was found to be an accurate, safe, and nonionizing way to diagnose and follow hematomas in pediatric patients.

Sonography of pediatric neck masses.

Duplex/color Doppler ultrasound is the imaging modality of choice for the evaluation of soft tissue masses of the pediatric neck. Information regarding the size, shape, borders, location, internal consistency and vascularity of the mass, and its relationship to the major neck vessels may be rapidly obtained. If the lesion is too large to be completely imaged within the ultrasound field of view available or malignancy is suspected, computed radiography or magnetic resonance imaging is required before surgical removal. Scintigraphy is reserved for evaluation of midline masses, which are thought to be due to ectopic thyroid, to determine preoperatively if the mass is the patient's only functioning thyroid tissue. Correlation of the sonographic findings with the clinical information narrows the differential diagnosis; thus, more appropriate therapeutic decisions can be made. When indicated, ultrasound-guided interventional procedures can be performed for diagnosis and/or treatment.

Intussusception.

Intussusception is the most common cause of intestinal obstruction in children between 3 months and 6 years. Intussusception occurs when a more proximal portion of bowel invaginates into more distal bowel. These patients often present with a wide range of non-specific symptoms, with less than one quarter presenting with the classic triad of vomiting, abdominal pain, and bloody stools. Thus, the diagnosis continues to rely on clinical suspicion. This review article discusses the clinical presentation of intussusception and the state-of-the art diagnostic and treatment options, as well as a review of the pertinent literature.

Sonography of hip dysplasia.

Early diagnosis of developmental dysplasia of the hip (DDH) is important to institute appropriate treatment and reduce the incidence of long-term complications. Risk factors for DDH include genetic, developmental, mechanical, and physiologic factors. Physical examination using Ortolani and Barlow maneuvers is standard for early detection. Plain film radiography is limited for the diagnosis of DDH even when applying several classic landmarks, lines, and measurements, due to the lack of visualization of the cartilaginous components of the infant's hip. Ultrasound arose as a tool for evaluation of the cartilaginous structures of the hip in the early 1980s. Graf's method of examination by ultrasound stresses morphology, whereas dynamic examination uses physical maneuvers to elicit laxity of the hip. The Pavlik harness is the mainstay of treatment of DDH in the young infant, and ultrasound examination in the harness is useful to monitor progress. Closed or open surgical reduction is reserved for unresponsive or advanced cases. Universal ultrasound screening of newborns is not deemed cost effective by most North American authors, although in Europe non-selective screening has been more widely used.