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Society for Pediatric Radiology – Poster Archive

Alexis Maddocks

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Showing 5 Abstracts.

Intraabdominal cystic lesions are relatively common prenatal diagnoses. Determining its etiology and diagnosis can be challenging on prenatal imaging. Fetal MR is a helpful imaging modality that can provide additional anatomic and physiologic information. The purpose of this study is to evaluate MR imaging findings of fetal intraabdominal cystic lesions with correlation with postnatal imaging and outcome. Read More

Meeting name: SPR 2017 Annual Meeting & Categorical Course , 2017

Authors: Ayyala Rama, Maddocks Alexis, Anupindi Sudha, Victoria Teresa

Keywords: Fetal, MRI, Cyst

Post-Transplant Lymphoproliferative Disease (PTLD) is a polyclonal and monoclonal lymphoid proliferation which occurs in 1-20% of solid organ transplant recipients. It is most common in multivisceral organ transplants followed by small bowel transplants, heart and lung transplants and less commonly in liver and kidney transplants. PTLD has a bimodal distribution of occurrence with the largest peak occurring within 1 year after transplantation and a second peak at approximately 4-5 years after transplantation. The Epstein Barr virus (EBV) is associated in 50-70% of cases. EBV seronegativity in the recipient at the time of transplant predicts a 2-4 times increased risk of PTLD especially if they receive a donor organ which is positive for EBV. This may explain the higher incidence in the pediatric population who tend to be seronegative for EBV. The World Health Organization (WHO) identifies four pathologic categories of PTLD: early lesions, polymorphic type, monomorphic type and classic Hodgkins lymphoma. The majority of PTLD cases are caused by B-lymphocyte proliferation in a T-cell depleted environment in the setting of immunosuppression. However, there is a subset of cases that are caused by T-cell or natural killer cells as well as cases that occur in the setting of negative EBV. Multiple clones of proliferating B-cells can be seen in a single patient. 2/3 of cases have diffuse expression of CD20 which is an important target for therapy. PTLD may be focal or diffuse and can manifest in a variety of different organ systems or even in the allograft itself. There is a higher percentage of extranodal disease in PTLD as compared to immunocompetent patients with lymphoma. The GI tract and liver are most commonly involved. Isolated lymph node involvement in comparison is less common in patients with PTLD. Central nervous system (CNS) involvement is relatively rare in PTLD. This educational exhibit will provide a pictorial review of PTLD and illustrates cases from one of the busiest transplant centers in North America to highlight the major imaging findings as well as complications seen on imaging of this disease. Extranodal and nodal disease will be demonstrated on multiple modalities as well as complications of this disease including intussusception and biliary obstruction. CNS disease will also be shown. The clinical manifestations, imaging characteristics, prognosis and treatment will be discussed and depicted. Read More

Meeting name: SPR 2019 Annual Meeting & Postgraduate Course , 2019

Authors: Maddocks Alexis, Fenlon Edward, Chen Susie, Ruzal-shapiro Carrie, Jaramillo Diego

Keywords: PTLD

Congenital pulmonary airway malformations (CPAM), bronchopulmonary sequestrations (BPS), and hybrid lesions are the most common congenital lung lesions. They are primarily diagnosed prenatally via ultrasound and further characterized by MRI. While most affected neonates are asymptomatic at birth, some may experience varying severities of respiratory distress requiring intervention. We seek to develop a prognostic model for prediction of post-natal outcomes in patients with congenital lung lesions using fetal MRI calculated observed to expected normal lung volume (O/E NLV). Read More

Meeting name: SPR 2019 Annual Meeting & Postgraduate Course , 2019

Authors: Maddocks Alexis, Ayyala Rama, Jacobs Shimon, Miller Russell, Duron Vincent

Keywords: CPAM, prenatal, MRI

Proximal humeral epiphyseal fracture-separation is a rare fracture pattern in infants often associated with birth-related or non-accidental trauma, representing a Salter-Harris type I or type II fracture. Lack of a proximal humeral epiphyseal ossification center in most newborns or only subtle displacement of a small epiphyseal ossification center in older infants, makes this injury difficult to diagnose on plain radiographs, potentially leading to delayed diagnosis or misdiagnosis. Ultrasound and MRI are therefore useful imaging modalities in indeterminate cases. Clinical findings of infant proximal humeral epiphyseal fracture-separation such as shoulder swelling, tenderness, and decreased active motion, overlap with more common entities including clavicular fracture, brachial plexus injury and osteomyelitis. Radiographs are often the first diagnostic study ordered to evaluate these symptoms but are insensitive due to minimal ossification of the proximal humeral epiphysis. Radiographs may be normal or show subtle displacement of the epiphyseal ossification center, apparent joint space widening, small metaphyseal fracture fragments or displacement of the proximal humeral metaphysis in relation to the scapula. These findings can be misdiagnosed as shoulder dislocation or pseudosubluxation due to a joint effusion. Careful review of the medical record may elucidate a history of difficult delivery with shoulder dystocia or suspected shoulder trauma. Ultrasound and MRI are useful in indeterminate cases due to their ability to resolve the cartilaginous physis and proximal humeral epiphysis, and to resolve their relationship to the humeral shaft and cartilaginous labrum. Ultrasound has higher anatomic resolution and offers the flexibility to quickly image the asymptomatic contralateral shoulder and image in planes that best show the relationship between the non-ossified epiphysis and the humeral shaft. Doppler ultrasound demonstrates epiphyseal perfusion without the need for contrast administration, and serial ultrasound imaging can be used to evaluate healing and remodeling. MRI is more useful in evaluating cases where osteomyelitis and/or septic arthritis are being considered, or in cases of an inconclusive history suspicious for non-accidental trauma to evaluate for additional osseous and soft tissue injuries. Several examples of typical proximal humeral epiphyseal fracture-separations in infants will be presented and the relevant imaging findings discussed. Read More

Meeting name: SPR 2019 Annual Meeting & Postgraduate Course , 2019

Authors: Fenlon Edward, Degnan Andrew, Maddocks Alexis, Chen Susie, Jaramillo Diego

Keywords: Fracture, Infant, Trauma

Monochorionic multiple gestations are at risk for complications related to a shared placenta. In utero therapies such as fetoscopic laser and radiofrequency ablation (RFA) are used to treat these complications. Previous work at our institution demonstrated a low rate of neuroanatomical abnormalities on post-therapy fetal imaging. The purpose of this study was to evaluate postnatal neurological outcomes within the same cohort. Read More

Meeting name: SPR 2017 Annual Meeting & Categorical Course , 2017

Authors: Soun Jennifer, Ayyala Rama, Maddocks Alexis, Miller Russell, Simpson Lynn, Laifer-narin Sherelle

Keywords: Fetal, MRI, Brain