ABSTRACT
MRI has become a major diagnostic tool in ophthalmology for evaluation of ocular pathology. There is excellent delineation of anatomy of the ocular globe with MRI, and specific characteristics of derangement of anatomy by pathological processes are well delineated by MRI. Optimum MRI technique for evaluation of ocular pathology were discussed. Various entities of the ocular globe where MRI is useful in the detection and estimation of the extent of the pathological process and their specific MRI characteristics were discussed, including retinoblastoma, ROP, PHPV, uveal melanoma, choroidal hemangioma, and simulating lesions.
Subject(s)
Eye Diseases/diagnosis , Magnetic Resonance Imaging , Eye Neoplasms/diagnosis , HumansABSTRACT
1H MR spectra were recorded from human gastrocnemius muscle at 63.86 MHz using the body coil of the Signa scanner as transmitter and a 3-in. surface coil as receiver. The fat content of the muscle was quantified relative to that of water in a selected volume or slice. The fat/water ratio was 0.05-0.07 for normal muscle but increased to 0.5-6.0 in primary and secondary muscular disorders such as Duchenne and myotonic dystrophy, Charcot-Marie-Tooth and polio muscular atrophy, cerebral palsy, and spina bifida. In Werdnig-Hoffmann spinal atrophy the ratio was above 10. Water-suppressed and slice-selective 1H spectroscopy was used for qualitative analysis of fat. The 1H profile of gastrocnemius muscles between healthy individuals and patients with neuromuscular diseases showed two major differences. In the normal muscle spectra, the resonance from the -(CH2)n- protons at 1.6 ppm was the most pronounced, whereas in the diseased muscle spectra resonances also appeared between 1.1 and 1.4 ppm. Some diseased muscle spectra showed multiple resonances from -CH = CH- in polyunsaturated fatty acids between 5.5 and 7.0 ppm. The corresponding resonances from = CH-CH2-, 1.9-2.0 ppm, and = CH-CH2-CH =, 2.7-2.9 ppm, were also seen. These peaks are usually not detected in normal muscle.
Subject(s)
Adipose Tissue/analysis , Magnetic Resonance Spectroscopy , Muscles/analysis , Neuromuscular Diseases/metabolism , Humans , Leg , Muscles/anatomy & histology , Neuromuscular Diseases/pathologyABSTRACT
Cortical heterotopia is a rare disorder of migrational brain development. A case of subependymal cortical heterotopia is reported. Usual clinical features and specific computed tomography findings are discussed.
