Ofer Arnon

Selectivity of a bromelain based enzymatic debridement agent: A porcine study

BACKGROUND Debridement of the burn eschar is a cornerstone of burn wound care. Rapid enzymatic debridement with a bromelain-based agent (Debriding Gel Dressing-DGD) has recently been investigated. The current study was designed to further investigate the selectivity of DGD to burned eschar in a larger number and more varied types of wounds. METHODS A systematic animal experiment was conducted to determine the effects of DGD on normal, non-injured skin, burns, exposed dermis of donor sites, and skin punch biopsy wells. Partial thickness dermal burns and partial thickness skin graft donor sites were created on a pig and treated with a 4-h application of DGD or its control hydrating vehicle that does not have any activity except hydration. Punch biopsy samples were taken before and after treatment and microscopically assessed for evidence of tissue viability and its respective components thickness. RESULTS Rapid dissolution of the burn eschar was noted in all DGD but not vehicle treated burns. There was no apparent damage to the underlying sub eschar dermis, donor sites, normal skin or punch biopsy wells after exposure to DGD. While the thickness of the treated tissues slightly increased due to edema, the increase in dermal thickness was similar after treatment with DGD or its vehicle. The increase in the cross section surface area of the treated punch biopsy wells was similar after treatment with DGD and its control vehicle. CONCLUSIONS Exposure of the burn eschar to DGD results in its rapid dissolution. Exposure of normal skin or non-burned dermis to DGD has no effects demonstrating its selectivity to eschar.

An analysis of pain and analgesia after Mohs micrographic surgery.

BACKGROUND Pain characteristics and analgesia in patients undergoing Mohs micrographic surgery have not been systematically studied. It is important to know about pain after Mohs micrographic surgery to better serve patient needs. OBJECTIVE We sought to measure pain in patients after Mohs micrographic surgery, and to investigate the relationship among postoperative pain, surgical characteristics, patient characteristics, and analgesics used. METHODS The Wong-Baker 0-to-10 pain scale was prospectively administered postoperatively to all patients presenting for Mohs micrographic surgery in a private practice setting between October 1, 2007, and December 31, 2008. Patients recorded their pain level from the day of surgery through postoperative day 4. The age, sex, location of surgery, number of lesions operated on, postoperative size, type of repair, severity of pain, and oral analgesics consumed and dosages used were recorded. RESULTS A total of 433 patients were included in the final analysis. The highest pain scores were found on the day of surgery and steadily declined until postoperative day 4 (P < .000). In all, 52% of patients took pain medication on the day of surgery, which declined successively with each postoperative day. The highest mean pain scores were statistically significantly associated with repair type (flaps), age (<66 years), number of lesions, and consumption of narcotics for pain relief. No statistically significant differences existed for sex or postoperative defect size. LIMITATIONS The instrument used to measure pain relied on patient self-report in a private practice surgery center. Only the validated Wong-Baker pain scale was used to assess pain in this study. CONCLUSION Approximately half of the patients after Mohs micrographic surgery take medication for pain control. Type of closure, location of surgery, age, and type of pain medication taken were significantly associated with postoperative pain.

Differential optical spectropolarimetric imaging system assisted by liquid crystal devices for skin imaging

Skin cancer diagnosis depends not only on histopathological examination but also on visual inspection before and after the excision of suspected lesion. Neoplasm is accompanied with changes in birefringence of collagen, pleomorphicity, and hyperchromatic state of epithelial nuclei. These phenomena can be measured by spectral and polarization changes of light backscattered by the examined tissue. A new differential spectropolarimetric system is proposed using liquid crystal devices, one as a tunable filter and the other as a polarization rotator, both operating at wide spectral ranges from the visible to the near-infrared. Since collagens fibrils texture orientation depends on its location in the skin and since it is not well organized, our system scans the bipolarization states by continuously rotating the linearly polarized light incident on a skin lesion, and collecting differential contrasts between sequenced images when simultaneously averaging the statistical readout of a video camera. This noninvasive method emphasizes areas on skin where the neoplasm, or tumor, minimizes the statistical polarization change of the scattered light from the lesion. The module can be considered as an assistant tool for epiluminescence microscopy. Images of skin tumors were captured in vivo before the patients having their surgery and compared to histopathological results.

Skin biomedical optical imaging system using dual-wavelength polarimetric control with liquid crystals

Spectropolarimetric skin imaging is becoming an attractive technique for early detection of skin cancer. Using two liquid crystal retarders in combination with a dual-band passive spectral filter and two linear polarizers, we demonstrate the spectral and polarimetric imaging of skin tissue in the near infrared. Based on this concept, a compact prototype module has been built and is being used for clinical evaluation.

Galactorrhea complicating wound healing following reduction mammaplasty.

Galactorrhea complicating wound healing following reduction mammaplasty occurs rarely; only isolated cases have been reported in recent years. We report the case of a 25-year-old woman who presented with delayed healing and dehiscence of surgical wounds 3 weeks following vertical scar reduction mammaplasty. During surgical debridement, spontaneous discharge of milk in the wound was noted. Serum prolactin levels were high, and she was treated with carbegoline, a dopamine agonist, which suppressed the prolactin secretion and led to rapid cessation of lactation. A second debridement and delayed primary closure were performed to achieve a satisfactory postoperative result.

Double-Bladed Scalpel in Mohs Micrographic Surgery

Mohs micrographic surgery is a tissue-sparing technique that allows for excision of cutaneous tumors under complete microscopic margins control. Mohs surgery boasts high cure rates and maximum tissue conservation. We introduce the double-blade scalpel in Mohs surgery as a timesaving and easy way to harvest tissue strips of uniform width and therefore increase the intraoperative efficiency of the procedure.