Ken-ichi Homma

Successful preservation of human skin by vitrification

The vitrification technique was applied to the preservation of human skin. This technique was simple, and no expensive equipment was needed. Split-thickness human skins from 8 patients were immersed in vitrification solution for 10 minutes at room temperature, immediately plunged into a liquid nitrogen tank, and cryopreserved for 3 weeks. The vitrification solution consisted of 40% ethylene glycol (vol/vol) and phosphate buffered saline solution that contained 30% Ficoll 70 (vol/vol; Wako Junyaku, Co, Tokyo, Japan) and 0.5 mol/L sucrose. The viability of vitrified and cryopreserved skin was evaluated with the trypan blue dye exclusion test, the methyl-thiazoldiphenyl-tetrazolium (MTT) colorimetric assay, and a culture test of the keratinocytes obtained from vitrified skin. The results of the trypan blue dye exclusion test showed 87.4% of viable cells, and MTT developed an average 0.817 absorbance. When vitrified skin was compared with 4 degrees C refrigerated skins after 3 weeks of storage, the difference of viability was significant both on the trypan blue dye exclusion test (P < .05) and on the MTT assay (P < .01). However, there was no significant difference in the viability of vitrified skins compared with fresh skin. Furthermore, keratinocytes from vitrified skin grew uneventfully in culture test. We used these vitrified skin allografts for patients with flame burns and electric burns. These allografts took well in both cases and promoted wound healing. We concluded that the vitrification method for skin preservation is simple and reliable, and this method could contribute to skin banking.

Razor-assisted treatment of axillary osmidrosis.

Shaving off the sweat glands and hair follicles with a single-use safety razor is described.

Prefabricated flaps using tissue expanders : An experimental study in rats.

The aim of this study was to determine if muscle vascularized pedicle flaps (MVP flaps) elevated in expanded tissue on the rat would survive to the same or greater area than flaps elevated in nonexpanded tissue. The animals were divided into three groups: group I (n = 10), with a tissue expander; group II (n = 10), with a tissue expander but not expanded; and group III (n = 10), with a thin silicone sheet (Biobrane). The mean surviving area of group I (96.6 ± 3.6 percent) was statistically higher than that of group II (73.2 ± 24.7 percent) (p < 0.05) and group III (59.5 ± 25.1 percent) (p < 0.005). These experiments demonstrate that there is a larger area of flap survival in expanded muscle vascularized pedicle flaps than that found in nonexpanded flaps in rats. The mechanism of increased vascularity associated with tissue expansion is still unclear, but microangiography of flaps showed increased vascularity of the pedicle itself, especially in group I.

Color Doppler sonography in monitoring after free jejunum transplantation

The authors assessed the usefulness of color Doppler imaging in the monitoring of vascular circulation after free jejunum transplantation. Seven male patients were examined daily with color Doppler sonography for the first postoperative week between 1999 and 2000. All sonographic examinations were performed with an SSD5500 ultrasound scanner. Arterial and venous signals were documented reliably in all patients. The flashing red spots around the serosal wall revealed the patency of the anastomosed artery and vein. No failures of the graft occurred. The presence of the color Doppler signals was considered sufficient to define vascular patency. The real-time monographic (B-mode) examination revealed the thickness and the plicae circulares of the jejunum wall. These monographic (B-mode) images supported the viability of the transplanted jejuna. The authors found color Doppler sonography to be a reliable and effective form of monitoring after free jejunum transplantation.