Microstructural and mechanical characterization of human tissue at and adjacent to pressure ulcers.

This investigation evaluated the microstructural and mechanical properties of human skin at and adjacent to pressure ulcers (PUs). Healthy breast and leg tissue served as control tissue. The tissue was characterized through uniaxial tensile testing and histomorphometric analysis. The PU tissue had significantly fewer straight and wavy fibers, but the fibers present were significantly wider and longer than those found in the healthy control tissue. PU ulcer tissue tested in tension had significantly lower strains at peak stress, versus the control breast tissue. Tissue at and adjacent to PUs has undergone significant adaptation or remodeling, as a result of the pressure sustained by the tissue.

The fate of intraoral free muscle flaps: is skin necessary?

Intraoral free musculocutaneous flaps can be bulky and inflexible for reconstruction of mucosal and soft-tissue defects to the head and neck. Free muscle flaps alone can be much less bulky and restore better contour than musculocutaneous flaps. When using free muscle flaps, however, it was felt that a skin graft was needed for proper epithelialization without significant contracture. Nine patients, average age 59 years (range 42 to 71 years), six males and three females, underwent extirpation of head and neck tumors and reconstruction with free muscle flaps only. Mucosal defects from 4 x 4 to 12 x 10 cm (four floor of mouth, five hard palate) were filled. Reconstruction was done with seven free rectus abdominis muscle flaps and two internal oblique/iliac bone flaps. All flaps survived with no significant complications. There was one minor abdominal wound separation. All patients who were able to swallow started oral feedings by 2 weeks postoperatively. Total epithelialization of even the large defects was completed by 8 weeks. Histologic assessment revealed an early fibrin layer over the muscle at 1 week with eventual epithelialization that was indistinguishable microscopically from normal surrounding mucosa. There was some contracture in all the flaps, but this was not clinically significant, even in the large defects. Intraoral free muscle flaps offer a safe and reliable reconstructive method that has led to a good functional result.

Endoscopic implant evaluation and capsulotomy.

Clinical use of breast endoscopy was begun 5 years ago for the purpose of internal endoscopic capsulotomy. This limited role for the endoscope has been entirely displaced by its use for inspection of implants for leaks or rupture. The materials and equipment are readily available, the proper techniques are safe for patient and implant, the method is easily learned, and the evaluation has been reliable. This report describes our first 50 breast endoscopies and details the technique and the means of learning it. The accuracy is far superior to that of mammogram or ultrasound, and to date, there have been no infections or damaged implants from the technique as described.

Dose-response effects of pentoxifylline on erythrocyte filterability: clinical and animal model studies.

Ten patients with chronic occlusive arteriosclerosis received single oral doses of 100, 200, 400, 800, and 1200 mg pentoxifylline in a single-blind, placebo-controlled study. Blood samples were drawn at baseline and at 2 hour intervals for 6 hours. Drug and metabolite levels, as well as red cell filterability (deformability), were determined on all blood samples. Statistically significant dose-response increases of red cell filterability were found 4 and 6 hours after oral medication with the dosages of 200 to 1200 mg pentoxifylline. These changes were proportional to the plasma levels of pentoxifylline and metabolites 1 and 5 of this agent. Attempts were made to develop a suitable animal-screening method for agents with similar activity and to determine whether red blood cells in the absence of disease-related abnormalities may respond to this type of therapy. Five healthy Macaca arctoides monkeys were given 24 mg/kg pentoxifylline intravenously, and measurable but lesser increases in red cell deformability were recorded than in the patients.