Zawin Joan,  Buyukkaya Ayla

Final Pr. ID: Poster #: CR-031

Subcutaneous fat necrosis of the newborn (SCFN) is an infrequent, self-limiting panniculitis observed in neonates. We report an unusual presentation of SCFN in a premature infant who developed a progressively enlarging mass in the supraclavicular region. Lesions commonly develop on the shoulders, back, buttocks, thighs, and cheeks.
The patient was a male infant born via emergency cesarean delivery at 30 weeks and 6 days gestation due to fetal distress. Maternal history was significant for diabetes. His postnatal course was complicated by hypoglycemia, episodes of apnea associated with hypoxia, and hypotension.
Physical examination revealed a firm, non-tender, subcutaneous mass without overlying skin changes in the left supraclavicular area. Ultrasonography demonstrated ill-defined thickening of the subcutaneous fat with heterogeneous echogenicity and internal blood flow. MRI showed reduced T1 signal intensity lower than that of normal fat and increased signal on T2 and fat-suppressed T2 sequences, indicating abnormal subcutaneous fat.
The differential diagnosis included SCFN, infantile myofibromatosis, embryonal rhabdomyosarcoma, hemangioma, and neurofibroma. Embryonal rhabdomyosarcoma is the most prevalent tumor affecting young children. Unlike subcutaneous fat necrosis, however, rhabdomyosarcoma typically arises after the first few months of life. It usually presents as a solitary, rapidly growing, firm mass involving striated muscle. Infantile myofibromatosis commonly involves multiple sites, including the bone, lungs, heart, and gastrointestinal tract. Given the infant’s prematurity and clinical history of perinatal hypoxia, metabolic derangements, and maternal diabetes, SCFN was considered the most likely diagnosis.
While SCFN resolves spontaneously, the most significant potential complication is hypercalcemia, which occurs in approximately 28% of cases. Additionally, renal ultrasound should be performed to assess nephrocalcinosis and nephrolithiasis.
In summary, subcutaneous fat necrosis may be present in premature infants with relevant perinatal risk factors. Its clinical and radiologic features can mimic neoplastic or infectious conditions. It is essential for radiologists to recognize the clinical and imaging characteristics of this rare condition to enable timely diagnosis and avoid unwarranted surgical intervention. Read More

Authors:  Zawin Joan , Buyukkaya Ayla

Keywords:  Soft Tissue Mass, MR, Ultrasound

Eliades Sarah,  Pomeranz Christy,  Baad Michael,  Roytman Michelle,  Kovanlikaya Arzu

Final Pr. ID: Poster #: EDU-056

Ultrasound is typically the first-line imaging modality for the evaluation of superficial soft tissue masses in the pediatric population. While certain superficial soft tissue masses have a classic appearance on ultrasound, others may have a nonspecific appearance and may vary in their sonographic characteristics. This can make a definitive diagnosis and follow-up recommendations difficult, especially for trainees.

We aim to provide a basic overview of some of the common and less common superficial soft tissue masses that may be encountered in pediatric imaging, and introduce a novel, structured algorithmic approach for evaluating these lesions on ultrasound. The algorithm will assist the radiologist in reaching a definitive diagnosis or narrowing the differential such that a helpful recommendation for further workup can be made. For example, the algorithm will include internal vascularity, border distinctness, cystic or solid components, presence or absence of calcifications, and location in the body and within the superficial soft tissue layers. Pictorial examples of each sonographic feature in the algorithm will provide further assistance.

Pathologies will include but not be limited to: pilomatricoma, glanuloma annulare, epidermal inclusion cyst, ganglion cyst, abscess/infection, lipoma, hematoma, lymph nodes, vascular anomalies, and soft tissue sarcomas. When a definitive diagnosis is not achievable, this algorithm will help the radiologist determine the likelihood of benignity, a short differential diagnosis, and a recommendation for any further imaging workup. Read More

Authors:  Eliades Sarah , Pomeranz Christy , Baad Michael , Roytman Michelle , Kovanlikaya Arzu

Keywords:  Soft tissue mass, Ultrasound, Superficial

Chitalkar Sachin,  Shet Narendra

Final Pr. ID: Poster #: EDU-055

To review the characteristic imaging findings of pediatric fibroblastic/myofibroblastic masses to aid in their diagnosis and management.
Soft tissue lesions in pediatric patients encompass a wide variety of pathologies. While a comprehensive review of all possible pathologies is beyond the scope of this poster, we aim to review one particular subset of lesions, fibroblastic lesions (including myofibroblastic neoplasms), in hopes to bring these to mind when evaluating a pediatric soft tissue mass to improve diagnosis and management of these entities.
Soft tissue masses typically present clinically on the basis of history and physical examination. US and MRI are used as first- and second-line imaging modalities, with limited roles for radiographs, CT and FDG-PET. In this poster, we will review the pertinent imaging findings of these neoplasms. Read More

Authors:  Chitalkar Sachin , Shet Narendra

Keywords:  Soft Tissue Mass, Soft-Tissue Tumors, Pediatric Radiology

Ziehe Luis,  Navarro Oscar

Final Pr. ID: Poster #: CR-035

Talar callosity, also known as foot pressure pad, is relatively rare in children. It is characterized by the development of a localized thickening of the skin and subcutaneous tissues on the dorsolateral aspect of the hindfoot to midfoot, most commonly at the level of the talus, navicular, or cuboid bones, and is attributed to repetitive pressure of the soft tissues against the bone. Such mechanical stress typically occurs in children who frequently maintain flexed leg positions with direct pressure on the dorsolateral foot, often in the absence of footwear.
The clinical course of talar callosity is benign, tending to remain stable over time as long as the underlying positioning persists. Clinically, talar callosity can be uni or bilateral and may present as focal skin hyperpigmentation and hyperkeratosis, which is often more obvious during foot adduction and plantar flexion. The true prevalence of this condition is likely underestimated, as it is typically asymptomatic and does not cause pain or functional impairment. The most frequent reason for medical consultation is the parental concern generated by the appearance of a painless nodule on the dorsum of the foot.
Although clinical diagnosis is usually straightforward, imaging studies may be requested when the lesion is mistaken for other entities, such as ganglion, vascular malformations, or soft tissue tumors. In such scenarios, ultrasound is the preferred initial imaging modality.
This exhibit illustrates five ultrasound-documented cases of talar callosities in children aged 4-10 years, two of which also had investigation with MRI. In each case, the ultrasound showed a partially defined, heterogeneous, hypoechoic thickening of the subcutaneous tissue, typically with an ellipsoid morphology, measuring between 1.3 cm and 1.8 cm in the maximal dimension, with absence of significant vascularity, and no involvement of tendinous or deep osseous structures, in keeping with the previously reported cases in the literature. MRI showed the lesions but did not add any further information to aid in the final diagnosis.
Recognition of this benign entity by clinicians and radiologists is crucial, as it can prevent unnecessary diagnostic procedures and invasive interventions, such as biopsy. The primary objective of this exhibit is to increase awareness of talar callosity among radiologists, thereby promoting accurate diagnosis and reducing the frequency of unwarranted investigations and decreasing parental concern. Read More

Authors:  Ziehe Luis , Navarro Oscar

Keywords:  Soft Tissue Mass, Benign