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E C McClees

Publications and source records attributed to E C McClees.

9 recordsLinked to original sources
PubMed1984

Assessing the activity of sarcoidosis: quantitative 67Ga-citrate imaging.

Three different methods of quantitating 67Ga-citrate lung images--a visual index, a computer-assisted index, and the total-lung-to-background ratio--were compared in 71 studies of patients with biopsy-proven sarcoidosis. Fifty consecutive cases were analyzed independently by two different observers using all three methods. In 45 patients, both gallium lung scans and bronchoalveolar lavage were performed within 2 weeks. In these studies, each index was correlated with the cell differential in the bronchoalveolar lavage fluid. The total-lung-to-background ratio proved to be the simplest to perform; correlated best with the original visual index (r = 0.81, p less than 0.00001) and the percentage of lymphocytes obtained in bronchoalveolar lavage fluid (r = 0.39, p less than 0.004); and showed the lowest interobserver variation. Sensitivity for detecting active disease was 84% compared with 64% and 58% for the visual and computer-assisted indices, respectively, with no sacrifice in specificity.

Cell Count↗
PubMed1984

Thoracic findings in gastrointestinal pathology.

A large variety of gastrointestinal and abdominal pathologic processes can be diagnosed or suspected by their direct effects on the chest. The chest radiograph, as often the first admission film, can aid the radiologist in recommending the appropriate follow-up examinations.

Adult↗
PubMedDate not supplied

A phantom study of intracranial CSF signal loss due to pulsatile motion.

MR imaging of the head often reveals localized areas of decreased signal intensity (flow voids) within the CSF. These flow voids are caused by turbulence within the CSF resulting from its pulsatile back-and-forth flow through the cerebral aqueduct and foramina. We describe a phantom that mimics the essential features of the CSF flow, and discuss its use in studying the dependence of the CSF flow void (CFV) on spin-echo (SE) and inversion-recovery pulse sequence parameters. The phantom had fluid-filled spaces to represent ventricles, and channels connecting these spaces to represent the aqueduct and foramina. A pump pushed the fluid in a pulsing manner through the phantom at various rates. The CFV was quantified by measuring signal loss relative to nonflowing fluid. The CFV did not appear to depend on repetition time or inversion time. The CFV was, however, strongly dependent on echo time (TE), and for single-echo SE sequences CFV became less severe as TE decreased. An even-echo rephasing effect was observed for multiecho sequences. Slice thickness and field of view also affected the appearance of the CFV, as did gating with respect to the pulsatile motion. These results imply that TE, field of view, slice thickness, and gating must be considered when using the appearance or absence of the CFV in diagnosis.

Cerebrospinal Fluid↗