MRI findings in juvenile Huntington's disease.

Juvenile Huntington's disease is a rare neurodegenerative disorder that first affects the basal ganglia. Presented here is a case of juvenile Huntington's disease in an 8-year-old male. Clinical features included epilepsy and developmental delay. Imaging findings showed severe atrophy of the caudate nuclei and putamina which prompted a genetic evaluation. The diagnosis was confirmed via molecular analysis which revealed the amplified CAG triplet characteristic of this disorder. This case report highlights the imaging features common in this rare cause of pediatric epilepsy.

CT and MRI findings in infantile vanishing white matter.

Infantile vanishing white matter disease is an uncommon cause of developmental delay and seizures in children. Presented here is a case of vanishing white matter disease diagnosed at 6 months of age. Imaging findings demonstrated widespread white matter abnormalities throughout the supratentorial and infratentorial brain. The diagnosis of infantile vanishing white matter disease was confirmed via molecular analysis which revealed a rare mutation in the gene responsible for this disorder.

ACTA2 leukovasculopathy: A rare pediatric white matter disorder.

A 3-year-old girl presented with ataxia, dilated pupils, and behavioral change prompting work up for stroke. Her medical history included chronic mydriasis and patent ductus arteriosus requiring aortoplasty. Magnetic resonance imaging of the brain demonstrated confluent white matter signal abnormality concerning for leukodystrophy. Magnetic resonance angiography revealed a cerebral vessel arteriopathy with a "broomstick appearance" and other neuroradiographic findings consistent with ACTA2 mutation. Pathogenic Arg179His ACTA2 mutation was confirmed in the patient. ACTA2-related leukovasculopathy should be considered during workup of patients with abnormal white matter (eg, leukodystrophies), childhood stroke, and arteriopathies. Recognizing the combination of commonly associated physical and medical conditions associated with radiographic features of this neurogenetic condition will prompt appropriate care and screening for comorbidities associated with this disorder.

Third ventricle choroid plexus papilloma: 2 cases.

The third ventricle is an uncommon location for choroid plexus papillomas. In adults, these tumors most commonly occur in the fourth ventricle. In children, they are more commonly found in the lateral ventricles. When these lesions are discovered in the third ventricle, they are often posteriorly located. Hydrocephalus and macrocephaly are typical sentinel findings. We present 2 cases of this uncommon presentation of third ventricular choroid plexus papilloma.

CT and MRI findings in leptomeningeal melanocytosis.

Leptomeningeal melanocytosis is a rare cause of seizure in the pediatric population. Shown here is a case of this disease in a 9-year-old male who presented with seizures and minor trauma. Imaging showed progression of leptomeningeal enhancement in the setting of increased seizure activity, and biopsy confirmed the diagnosis. The patient received immunotherapy but eventually succumbed to the disease. This case serves as an educational tool to improve awareness of melanocytic proliferation as a differential consideration for leptomeningeal enhancement.

Pontine tegmental cap dysplasia with a duplicated internal auditory canal.

Pontine tegmental cap dysplasia (PTCD) is a rare neurological syndrome that results in a hypoplastic ventral pons, tegmental cap at the dorsal pons, and cranial nerve dysfunction. The most common symptoms are hearing loss and speech problems. We present a case of a 9-month-old male who presented with developmental delay and hypotonia. Magnetic resonance imaging revealed ectopic dorsal transverse pontine fibers and a cap-like protrusion of the dorsal pons. Diffusion tensor imaging showed that the ventral pontine fibers were absent. The cause of PTCD is undiscovered, but proposed hypotheses include dysfunction in axonal guidance, neuronal migration, and ciliary protein function. PTCD is a rare neurological disorder, but the diagnosis can be suggested with MRI using diffusion tensor imaging as an aid.

Cystic fibrosis and Chiari type I malformation: autopsy study of two infants with a rare association.

Cystic fibrosis (CF), an epithelial cell transport disorder caused by mutations of the cystic fibrosis transmembrane conductance regulator (CFTR) gene, is not generally associated with malformations of the central nervous system (CNS). This report describes two African-American children who died at less than 2 years of age with known Chiari I malformations and were found, unexpectedly at autopsy, to have the classic pancreatic and respiratory changes of CF. Both patients had suffered from failure to thrive that had been attributed to their CNS malformations. One child also had recurrent pneumonia and died with Pseudomonas sepsis. Mutational analysis for > 70 common CFTR mutations identified a single delta F508 mutation in one patient and a single 3120+1G to A mutation in the other. Their second CFTR mutations were not identified. The association of CF with Chiari I malformation is not likely to be purely coincidental, as the probability of such an occurrence in African-Americans is greater than one in 7,500,000 patients. It is possible that the CFTR gene may play a previously unrecognized role in CNS development. Alternatively, this CNS abnormality may be acquired due to the metabolic and electrolyte imbalances that characteristically occur in CF.