Faculty Bibliography

BACKGROUND: Methylmalonic acidemia (MMA) is an autosomal-recessive inborn error of metabolism. OBJECTIVE: To recognize the CT and MR brain sectional imaging findings in children with MMA. MATERIALS AND METHODS: Brain imaging studies (47 MR and 5 CT studies) from 52 children were reviewed and reported by a neuroradiologist. The clinical data were collected for each patient. RESULTS: The most common findings were ventricular dilation (17 studies), cortical atrophy (15), periventricular white matter abnormality (12), thinning of the corpus callosum (8), subcortical white matter abnormality (6), cerebellar atrophy (4), basal ganglionic calcification (3), and myelination delay (3). The brain images in 14 patients were normal. CONCLUSION: Radiological findings of MMA are nonspecific. A constellation of common clinical and radiological findings should raise the suspicion of MMA.

An inherent drawback of the traditional diffusion tensor model is its limited ability to provide detailed information about multidirectional fiber architecture within a voxel. This leads to erroneous fiber tractography, results in locations where fiber bundles cross each other. In this paper, we present a deterministic two-tensor extended Streamline Tractography (XST) technique, which successfully traces through regions of crossing fibers. The method has been evaluated on simulated and in-vivo human brain data, and compared with the traditional single tensor, and a probabilistic tractography technique. By tracing the corticospinal tract we demonstrate that when compared to the two methods, our technique can accurately identify fiber bundles known to be consistent with anatomy. When compared to the dense connectivity maps generated by probabilistic tractography, the method is computationally efficient and generates discrete geometric pathways that are simple to visualize and clinically useful.

Chronic granulomatous disease (CGD) is a rare primary immunodeficiency disease characterized by recurrent life-threatening bacterial and fungal infections. We report a 4-month-old girl with CGD, was firstly presented with an anterior chest wall protrusion because of an aspergillosis mass.