Biomedical subjects
Publications and source records attributed to W R Oliver.
Image processing applications in forensic pathology are becoming increasingly important. This article introduces basic concepts in image processing as applied to problems in forensic pathology in a non-mathematical context. Discussions of contrast enhancement, digital encoding, compression, deblurring, and other topics are presented.
We used image processing to elucidate patterned injuries in a case of assault with a police baton. Three-dimensional visualization techniques were then used to correlate the location of patterned injuries with subjacent fracture and soft tissue damage. The visualization methods are discussed.
OBJECTIVE: To compare two visual enumeration methods to determine whether the confocal approach yielded better counts of chromosome-specific hybridization sites. STUDY DESIGN: Brightfield microscopy was used to count in situ hybridization (ISH) sites in 4-microns tissue sections. Confocal microscopy was used to collect three-dimensional (3D) data sets from fluorescence in situ hybridization (FISH) preparations made with sections of various thicknesses. Analysis of the confocal images relied on custom-built interactive visualization software. RESULTS: The confocal method yielded higher average counts of hybridization sites per nucleus due to fewer truncated nuclei in thicker sections and to visual exclusion of the truncated nuclei that remained. Optimal section thickness was 8-12 microns. Limited penetration by FISH reagents restricted the use of thicker sections. CONCLUSION: Analysis of intact nuclei visualized in three dimensions was more sensitive in demonstrating high centromere number than was brightfield ISH analysis of 4-microns sections. Improvements in semiautomated interactive software may make the confocal approach practical for accurate evaluation of chromosome number in precise histologic contexts.
Three-dimensional visualization is an important tool in the evaluation and demonstration of injury. Creating convincing graphics, however, requires strict distinction between illustrative and reconstructive visualizations and a method of validation. We present a case in which we used a radiation-planning tool to provide a 3-dimensional illustrative visualization of a contact gunshot wound to the head, and validated the result by comparing computed radiographs with radiographs taken at autopsy. We discuss the use of visualization tools for data exploration in forensic pathology.
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Although a great deal of understanding of blood cell locomotion can be derived from the evaluation of cell paths, cell movement may also be examined by evaluating how the cell changes shape as it moves. In order to understand how a cell changes shape, it is first necessary to be able to quantitatively describe cell shape and cell shape change. A review of current work in computer vision and shape description as applied to blood cells is presented.
Ewing's sarcoma is a rare tumor of the bone. In the Intergroup Ewing's Sarcoma Study (IESS) approximately 4% of the primary bone tumors arose in the bones of the head and neck. The mean age of patients was 10.9 years; boys slightly dominated the group. Signs and symptoms were local in distribution, with a mass or swelling most frequent. As in other sites, we categorized the dominant histologic pattern as diffuse or filigree, the latter carrying a more unfavorable prognosis. The radiographic appearance may be atypical as compared to Ewing's sarcoma at other sites. Prognosis of head and neck Ewing's is significantly better than Ewing's sarcoma overall. The gnathic bones were commonly affected, yet there was no associated mortality. No patient with primary disease in the bones of the head and neck who survived for 5 years on any of the IESS protocols has subsequently died.
Solitary schwannomas arising in the juxtadrenal region are exceedingly rare. A middle-aged woman with a confusing clinical course was found to have a solid periadrenal mass, which was surgically excised. The gross and light microscopic appearance of the tumor was suggestive but not diagnostic of this entity. However, electron microscopic evaluation of the neoplasm revealed prominent basal lamina and interdigitating cellular processes characteristic of a schwannoma. The diagnosis of schwannoma was further supported by the demonstration of S-100 protein, type IV (basement membrane) collagen, and laminin immunoreactivity by immunohistochemical techniques. The use of these special studies to arrive at the diagnosis in this case and in the larger context in the diagnosis of rare adrenal and periadrenal tumors of uncertain origin is fully discussed.
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This paper reports correlations between female sex role and attitudes toward male sexual dysfunction in a sample of 30 women. The findings mirror those of a related much larger study. Mechanisms that might explain these findings are explored.
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