Magnetic resonance imaging diagnosis of a skeletal dysplasia mimicking erosive arthropathy.

This case report of a 14-year-old boy with arthralgia and clinically suspected inflammatory arthropathy highlights how magnetic resonance imaging (MRI) ultimately diagnosed skeletal dysplasia. A genetic evaluation revealed a transient receptor potential vanilloid 4 (TRPV4) pathogenic variant. This is a rare description of the MRI appearance of this type of dysplasia in long bone epiphyses corresponding with the histological findings of disrupted endochondral ossification. This report offers imaging support to the description of endochondral bone growth disruption in TRPV4-related skeletal dysplasias.

Magnetic resonance imaging of the brain in glutaric acidemia type I: a review of the literature and a report of four new cases with attention to the basal ganglia and imaging technique.

RATIONALE AND OBJECTIVES: In glutaric acidemia type I (GA I), a pediatric neurometabolic disease that may be mistaken for nonaccidental trauma, expeditious detection is critical as early treatment may substantially improve psychomotor dysfunction. In this study, we examine in depth the magnetic resonance (MR) findings, with special attention to the basal ganglia, in 4 new cases and compare the findings with those described in the literature. METHODS: MR studies of 4 children, diagnosed to have GA I via cultured fibroblast enzyme studies or urine metabolite assays, were performed on a 1.5 T system in the axial plane using spin echo T(1)-weighted, fast spin echo T(2)-weighted, and fluid-attenuated inversion recovery (FLAIR) technique. Three of 4 patients were followed with serial exams to document temporal evolution of the disease. RESULTS: On T(2)-weighted images, abnormal increased signal intensity was seen in both the putamen and globus pallidus in all cases. However, in contradistinction to cases reported in the literature, involvement of the caudate nucleus was minimal or absent even on serial MR exams. In children 15 months and older, FLAIR improved recognition of basal ganglia and white matter abnormalities. The previously described widened cerebrospinal fluid spaces anterior to the temporal lobes, increased T(2)-weighted signal intensity in the periventricular white matter, and widened sylvian fissures characteristic of GA I were noted in all patients. CONCLUSIONS: Abnormalities of the caudate nucleus are not a prominent presentation of these patients and the absence of this finding should not exclude a diagnosis of GA I. FLAIR scans, as an adjunct to more conventional T(1)- and T(2)-weighted sequences, can play an important role in children 15 months or older despite immature myelination in these patients.