Biomedical subjects

J Wirth

Publications and source records attributed to J Wirth.

At least 55 records · Page 3Linked to original sources

PubMed1990

Histopathology of veins and venous valves of patients with venous insufficiency syndrome: ultrastructure.

Vein and vein valve biopsies were obtained from venous insufficiency syndrome (VIS) patients undergoing venous valve transplants. Normal control biopsies were obtained from other non-VIS procedures. The specimens were examined using light and transmission electron microscopy (TEM). Biopsies from VIS patients showed a variety of changes from what was considered normal structure. Most histopathologic changes were noted in the endothelium and subendothelial layer of the vein valve and wall, and in the media of the vein wall. These changes included 1) erosion of the endothelium with consequent adherence of blood elements, 2) intact endothelium with a thickened subendothelial zone which was populated with migrated smooth muscle and perhaps other cell types, 3) occurrence of abnormal or over-abundant collagen, and 4) thickening of the media with changes in the smooth muscle population therein.

Biopsy↗

PubMed1988

Silicone rubber temporomandibular joint (TMJ) meniscal replacements: postimplant histopathologic and material evaluation.

Medical grade silicone rubber has long been considered a suitable meniscal replacement, but there has been increasing concern about migration of this material into adjacent tissues. The objectives of this study were to determine the definitive composition of tissue-incorporated material which is presumed by light microscopy to be silicone and to identify long term histopathologic sequelae of meniscal replacements. Adult female patients underwent meniscectomy and replacement with silicone rubber (Silastic) implants. After 12 to 18 months, recurrence of symptoms in 8% of these cases led to implant removal with excision of peri-implant fibrous pseudocapsules. Excised tissues, including one preauricular lymph node and implants were submitted for light microscopy, SEM, and energy dispersive x-ray microanalysis (EDX) for the identification of elemental composition, critical surface tension measurement, and internal reflection infrared spectroscopy. EDX revealed prominent peaks for silicon in both pseudocapsular and nodal tissues. Morphologic findings surrounding the long-term implants included foreign body reaction, synovitis, dystrophic calcification, fibrocartilaginous metaplasia, hyalinization, and scarring. Particulate silicone debris induced a pathologic response in the tissues and migrated to nodes. These findings suggest that periodic evaluation be performed over the life of such implants to rule out breakdown under function. These findings should intensify the search for improvements or replacements for silicone rubber as an interpositional material in the temporomandibular joint.

Calcinosis↗

PubMed1988