Caudal cell mass developmental aberrations: an imaging approach.

The objective of this review is to describe antenatal and postnatal imaging criteria, which allow diagnosis and aid workup, prognostication and treatment of developmental anomalies of the caudal cell mass. The lower spinal cord (conus medullaris), filum terminale and inferior lumbar and sacral nerve roots develop from the caudal cell mass, a remnant of the embryologic primitive streak composed of undifferentiated pluripotential cells. Anomalous caudal cell mass development can manifest as tight filum terminale, caudal dysgenesis, terminal myelocystocele, anterior sacral meningocele or sacrococcygeal teratoma. Lower spinal cord development occurs simultaneously and in topological proximity to the developing lower gastrointestinal and genitourinary tracts, leading to coexistent malformations. We review the embryology of the caudal cell mass, describe the role of antenatal and postnatal imaging for diagnosing, staging, prognosticating and guiding intranatal or postnatal intervention for developmental anomalies of this region and briefly discuss clinical manifestations and treatment goals and strategies. An overview of antenatal imaging diagnosis of associated multisystem abnormalities will be provided where applicable.

Neonatal neuroblastoma 4s with diffuse liver metastases (Pepper syndrome) without an adrenal/extraadrenal primary identified on imaging.

We report the imaging appearances of a case of pathologically proven, neonatal neuroblastoma 4S with diffuse hepatic metastatic involvement at presentation. Patient had an abnormal appearing liver both by ultrasound and MR. There was no evidence for associated adrenal tumor by imaging. Lack of an associated adrenal mass led to initial misinterpretation of diffuse hepatic accumulation of MIBG seen with radionuclide scintigraphy. To the best our knowledge, this is the first report of metastatic neonatal 4S neuroblastoma without an adrenal (or extra-adrenal) primary identified either on pre- or post-natal imaging.

Neonatal distal femoral physeal injury secondary to mechanical trauma of birth: A case report.

Physeal injuries occurring secondary to neonatal birth-related trauma are rare entities. Most reported cases of physeal injury involve the distal humerus with only a few published case reports of proximal femoral involvement. So far, we have found only one reported case of neonatal distal femoral epiphysiolysis following Caesarean section. We hereby report a unique case of distal femoral physeal injury with at least partial epiphyseal separation following an uneventful, spontaneous vaginal delivery. Given the uneventful delivery and no known prenatal risk factors, the imaging findings were initially not recognized as being secondary to birth-related injury. Nonaccidental trauma and infection were considered among the possible etiologies for the clinical and imaging findings and a detailed workup for both these entities was performed. Distal femoral physeal injury was considered as a diagnosis of exclusion only after both initial differential considerations were excluded. The authors hope that a knowledge of this entity will facilitate a more accurate differential in cases of thigh swelling and hypomobility in the newborn.

CNS hemangioblastomatosis in a patient without von Hippel-Lindau disease.

We report on a case of disseminated CNS hemangioblastoma, also referred to as hemangioblastomatosis, involving the supratentorial compartment and the entire spine. The patient presented with new onset headache, gait difficulties and memory deficits many years following resection of a hemangioblastoma from the cerebellum. The patient's family history was negative for von Hippel-Lindau (VHL) disease, and his personal history was negative for any additional VHL-defining lesions. Imaging revealed extensive dural caking and nodularity both supratentorially and in the spine, along with scattered parenchymal tumors showing a more typical appearance for hemangioblastoma. Biopsy of the dural thickening revealed histologic features compatible with hemangioblastoma. Genetic testing for VHL was eventually completed, and no evidence of a germline VHL mutation was detected.

Bilateral Common Iliac Artery Endofibrosis in a Recreational Cyclist: Case Report and Review of the Literature.

External iliac artery endofibrosis is a rare medical condition typically encountered in young endurance athletes, mainly cyclists. Iliac endofibrosis usually develops in the external iliac artery and is rarely seen in the common iliac or in common femoral arteries. We describe a unique case of a patient who was not a professional or high-endurance cyclist. The lesions in our case appeared to be bilateral in the common iliac arteries and were not limited to the external iliac artery as most commonly described. We present an overview of the literature regarding this medical condition.

A Rare Triad of Giant Occipital Encephalocele with Lipomyelomeningocele, Tetralogy of Fallot, and Situs Inversus.

Giant encephalocele is an uncommon congenital anomaly with very few published reports available in the English literature. Tetralogy of Fallot associated with situs inversus is also infrequently reported. To our knowledge there are no published reports of an association between giant encephalocele and Tetralogy of Fallot. The additional finding of situs inversus results in a rare pathologic triad, not heretofore described.

Delayed Myocardial Enhancement in Cardiac Magnetic Resonance Imaging.

Delayed myocardial enhancement MRI is a highly valuable but non-specific imaging technique that is ancillary in the diagnosis of a variety of diseases including myocardial viability, cardiomyopathy, myocarditis and other infiltrative myocardial processes. The lack of specificity stems from the wide variety of differential diagnoses that may present with overlapping patterns of delayed enhancement. Many of these differential diagnoses have been presented and discussed in this article.

The quadricuspid aortic valve.

The quadricuspid aortic valve is a very rare congenital defect that may be an isolated entity or associated with a multitude of cardiovascular abnormalities. Isolated cases usually manifest late in life with the complication of aortic regurgitation, which can be delayed by early valve replacement. We present a case of quadricuspid aortic valve associated with truncus arteriosus, ventricular septal defect, and interrupted aortic arch.

A case of Rosai-Dorfman disease in a pediatric patient with cardiac involvement.

Rosai-Dorfman disease (RDD) involves abnormal proliferations of oddly behaving histocytes that are not derived from the Langerhan's Cell linage. These collections tend to occur within lymph nodes, with occasional extra nodal presentation. While RDD is a rare entity itself, extra nodal cases are even more so, with even fewer reporting cardiac involvement, and previously only in adults. This report describes the disease in a pediatric patient who had the unique feature of an extra nodal cardiac mass. The patient, who was known to have sickle cell disease, was initially erroneously thought to have acute chest syndrome. Sudden changes in the patient's status, including development of 3rd degree heart block, demanded investigation with additional imaging. Chest CT revealed a mass arising from the cardiac interatrial septum and encircling the entire thoracic aorta. Imaging features of Rosai-Dorfman disease are nonspecific, complicating the diagnosis. We present this case with discussion of this extremely uncommon entity. We describe the diagnostic methods, the differential diagnosis, and the treatment options.

Paucity of biliary ducts: A rare etiology of neonatal cholestasis.

We report a case of a newborn with cholestasis that was diagnosed as nonsyndromic Alagille syndrome. The main feature of the disease is a paucity of biliary ducts. There are two known types of the disease: the syndromic type which is associated with other congenital defects and the nonsyndromic type without other anomalies detected at birth. We describe the case and discuss its clinical and radiologic findings. We also discuss the various etiologies of cholestasis that are included in the differential diagnosis.

Unusual Concentration of Tc-99m methylendiphosphonate in Rhabdomyosarcoma.

Extraosseous accumulation of bone-seeking agents is rare, but has been previously reported in pediatric sarcomas and neuroblastomas. We present an unusual case of a 5-month-old male with an abdominal mass observed clinically by his parents and referring pediatrician. Contrast abdominal computerized tomography confirmed the presence of a large pelvic mass that was diagnosed pathologically as embryonal rhabdomyosarcoma. A bone scintigraphy that was performed for staging of the disease revealed accumulation of the radiopharmaceutical in the tumor. There was no evidence for skeletal metastatic disease. This case further demonstrates the nonspecificity of soft-tissue tumor uptake on bone scintigraphy.

Focal small-bowel localization of bone-imaging radiopharmaceutical in a child.

Bone scintigraphy is an important diagnostic tool in the evaluation of skeletal pathologic conditions. However, the extraskeletal uptake of bone-seeking radiotracers is still an unexpected finding in most cases. We present a 5-year-old male with an unexpected focal accumulation of the radiotracer in the small bowel. Bowel accumulation of bone-seeking radiopharmaceuticals has been seen previously in children in the colon and mainly in the cecum, but not in the small bowel. The mechanism for such accumulation is not completely clear and may be explained by focal histological disturbances of a small-bowel segment that contributed to excretion of the radiotracer from the blood-to-bowel lumen.

Molecularly confirmed primary malignant rhabdoid tumor of the urinary bladder: implications of accurate diagnosis.

Malignant rhabdoid tumors (MRTs) are well recognized in the kidney and extrarenal sites such as soft tissues, retroperitoneum, and bladder but are classified as atypical teratoid/rhabdoid tumors in the central nervous system. The unifying features of both extracranial MRT and atypical teratoid/rhabdoid tumors are the exon deletions/mutations of the SMARCB1 (SWI/SNF related, matrix associated, actin dependent regulator of chromatin, subfamily b, member 1) gene in 22q11.23 and resulting loss of SMARCB1/INI1 (integrase interactor 1) protein expression by immunohistochemistry. We herein report a case of extrarenal rhabdoid tumor confined to the bladder in a 3-year-old child, diagnosed by histopathology and confirmed by immunohistochemical and molecular studies. This is only the fourth molecularly proven primary MRT of the bladder to be reported. The patient's peripheral blood was negative for the deletions observed in the tumor, thereby confirming a sporadic origin for the tumor. Given the possible dismal outcome, urgency for definitive diagnosis to institute intensive multimodality therapy, histopathologic differential diagnosis with rhabdomyosarcoma and urothelial carcinoma with rhabdoid features, and lack of consensus management guidelines, oncologists, urologists, and pathologists must be aware of this entity. Evaluation for a germ line SMARCB1 alteration may greatly aid risk stratification and family planning.

Daughter cyst sign.

The daughter cyst sign is a specific indicator of an uncomplicated ovarian cyst and pathologically represents a stimulated ovarian follicle. This finding must be differentiated from an ectopic pregnancy in a patient who has the potential to become pregnant. We report an uncomplicated ovarian cyst in a 3-year-old female with McCune-Albright syndrome and precocious puberty mimicking an ectopic pregnancy.

Pediatric rhabdomyosarcoma at presentation: can cross-sectional imaging findings predict pathologic tumor subtype?

OBJECTIVE: The purpose of the study is to determine whether there are cross-sectional imaging features of pediatric rhabdomyosarcoma that are specific to the different pathologic subtypes of the tumor. MATERIALS AND METHODS: Medical records of 14 pediatric patients who were diagnosed with rhabdomyosarcoma were reviewed retrospectively. Patient demographics, including age and sex, as well as final pathologic report were obtained. The initial CT, MRI, or both obtained at presentation, prior to the diagnosis being established, were reviewed by two radiologists. We recorded tumor features including site, size, margins, local extension, and presence of metastases. Presence of calcification, hemorrhage, or necrosis as well as attenuation and heterogeneity of the tumor were also recorded. RESULTS: Ten of our fourteen patients were formally diagnosed with the embryonal subtype of rhabdomyosarcoma, while three were found to have the alveolar subtype, and one subtype was poorly differentiated. There was no significant difference in the attenuation and in the heterogeneity of the tumor between the embryonal and the alveolar subtype on CT. CONCLUSION: Imaging features at presentation, such as attenuation and heterogeneity, could not correlate to the pathologic subtype of pediatric rhabdomyosarcoma.