Biomedical subjects

W Smoker

Publications and source records attributed to W Smoker.

3 recordsLinked to original sources

PubMed1990

MRI in familial multiple sclerosis.

We obtained cranial MRIs of 76 individuals from 13 MS multiplex families. Thirty-one MS patients and 45 normal family members participated in the study. Twenty-eight of the 31 individuals with definite or probable MS had multiple white matter lesions by MRI. Thirty-five normal family members had normal MRIs, and 10 had abnormal studies. Four normal individuals under age 40 had abnormal MRIs. Three had multiple white matter lesions. The 4th had a single small white matter lesion in the left centrum semiovale. Six normal individuals over age 50 had multiple white matter lesions. Although diffuse white matter lesions in individuals over age 50 should be interpreted with caution, these lesions in individuals under age 40 with no history of underlying medical illness are suggestive of demyelination. The results of the present study indicate that subclinical MS may be present in apparently normal members of multiplex families.

Adult↗

PubMed1986

The tailored CT evaluation of persistent facial nerve paralysis.

The clinical, radiographic, and pathologic records of 39 patients with peripheral facial nerve dysfunction seen from October 1981 through July 1984 are reviewed. The extent of preradiologic clinical localization of suspected lesions and their subsequent pathologic confirmation is correlated to the number, sequence, and type of radiographic evaluations performed.

Adolescent↗

PubMedDate not supplied

Magnetic field strength dependence of chemical shift artifacts.

The dependence of proton MRI chemical shift artifacts on main magnetic field strength was investigated using three MR whole body systems from 0.3 to 1.5 T with both permanent and superconducting magnet designs. The magnetic field gradients varied from 0.09 to 1.0 gauss/cm. The image bandwidth varied from 8.54 to 32 kHz. Both phantoms and normal volunteers were studied. The chemical shift misregistration error in hertz was determined by the main magnetic field strength of the system which was proportional to the Larmor frequency. The actual image error in millimeters was determined by a combination of the shift in hertz as well as by the amplitude of the magnetic field gradients applied to form the image. Steeper gradients mapped a given shift in hertz onto a smaller millimeter displacement. The higher field strength systems tended to use steeper magnetic field gradients, but this increase was not enough to offset the higher absolute shift in hertz due to the higher Larmor frequencies. In general, the chemical shift in millimeters tended to increase with the increasing field strength despite the steeper imaging gradients. Based on these findings, strategies for minimizing the chemical shift artifact may be developed.

Adipose Tissue↗