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Transplantation Surgery (transplantation + surgery)
Selected AbstractsIntricacies of the Single-Scar Technique for Donor Harvesting in Hair Transplantation SurgeryDERMATOLOGIC SURGERY, Issue 6 2004Dominic A. Brandy MD Background. Although single-scar techniques have been published and are used by approximately half of all surgeons, this approach is not as common as one might suspect. Objective. The objective is to demonstrate several surgical gems that make the single-scar donor technique a viable method that can be performed by the vast majority of hair restoration surgeons. Methods. The author presents various techniques such as postauricular skin elevation, subcutaneous undermining of the nape scalp, debulking of underlying scar tissue, temporary staple closure, and permanent double-layered closure using magnification (preferably 2.5 × or greater). All of these contribute to a loose closure with an aesthetically pleasing single donor scar after multiple surgeries. Results. Utilizing the various techniques described in this article, the author has been able to achieve a cosmetically attractive single scar after multiple surgeries in the vast majority of patients. Conclusion. An aesthetically pleasing single, thin donor scar is preferable to multiple scars or a thick single scar at the donor area after multiple hair restoration surgical procedures. The author presents several methods that help hair restoration surgeons conquer some of the obstacles that have deterred them from performing a single-scar technique with consistently excellent results. [source] Enhancement of In Vitro Hair Shaft Elongation in Follicles Stored in Buffers That Prevent Follicle Cell ApoptosisDERMATOLOGIC SURGERY, Issue 1 2004Walter Krugluger MD Background. Viability and survival of stored micrografts during hair follicle transplantation are important limitations of micrograft transplantation procedures. In this study, we investigated the effect of different storage solutions and inhibitors of apoptotic cell death (ACD) on hair follicle cell viability by measuring in vitro hair shaft elongation (HSE) for 5 days. Methods. Micrografts from informed patients undergoing routine micrograft transplantation were stored for 5 hours at room temperature in phosphate-buffered salt solution (PBS) or HEPES-buffered Dulbecco's modified Eagle's medium (DMEM), containing different concentrations of the ACD-inhibitors aminoguanidine (AMG), hormones (insulin, hydrocortisone), 14,15-epoxy-eicosatrienoic acid (14,15-EET), or combinations of these. Results. In vitro, HSE was significantly increased in micrografts stored in DMEM compared with PBS (2.3%±0.6% vs. 28.4%±3.9%, P<0.0001). DMEM supplemented with AMG (10 ,g/mL) or 14,15-EET (1 ng/mL) further increased in vitro HSE (33.9%±7.1%, p=0.01, and 32.8%±6.1%, P=0.02, respectively). Evaluation of ACD in stored micrografts, performed by determination of cytoplasmic histone-associated DNA fragments, confirmed the results found by HSE. ACD was detectable after a 36-hour culture in serum-containing medium and was higher in micrografts stored in PBS compared with micrografts stored in DMEM (A405nm/A492nm: 1.63±0.21 vs. 1.42±0.07, respectively; P<0.01). The addition of AMG further decreased serum-induced ACD in the micrografts (DMEM 1.42±0.07 vs. DMEM/AMG 0.90±0.11, P<0.0001). Conclusion. Our study demonstrated an important role of ACD in micrograft transplantation surgery. Preconditioning of micrografts with storage buffers containing inhibitors of ACD could prevent serum-induced ACD after transplantation and might increase the viability of micrografts and the clinical outcome in micrograft transplantation. [source] The Distribution of Follicular Units in the Chinese Scalp: Implications for Reconstruction of Natural-Appearing Hairlines in OrientalsDERMATOLOGIC SURGERY, Issue 6 2002Ren-Yeu Tsai MD background. Follicular transplantation using hair in its naturally occurring groups, called follicular units (FUs), has become the most popular technique in hair restoration surgery. Recently follicular transplantation was performed with a qualitative and quantitative concept to achieve the best clinical result. The characteristics and distribution of FUs are well studied in Caucasians and widely applied in hair transplantation surgery. objective. In order to understand the normal distribution of FUs in the Chinese scalp, we counted the number of hairs and FUs in normal Chinese scalp to provide general information for surgical planning and design in bald Chinese patients. methods. A total of 50 normal and 50 bald Chinese adults were enrolled to count the hairs on their scalp. One hundred bald patients receiving hairline reconstruction were also prospectively quantitatively evaluated. results. In normal Chinese scalp, an average 71.78 FUs/cm2 and 137.08 hairs/cm2 were calculated with a follicular density of 1.91 hairs/FU. Two-hair FUs are the predominate group (50.29%). In bald patients, an average of 68.07 FUs/cm2 was found, which was less than that of the occipital scalp in normal nonbald patients. In reconstruction of the frontal hairline, a total of 700,1000 FUs were implanted with an average density of 30 FUs/cm2. conclusion. We found the average number of FUs (0.72 FU/mm2) was less than that in Caucasian patients (1 FU/mm2). The average density of 30 FUs/cm2 implanted was suitable to reconstruct a natural frontal hairline in bald Chinese patients, which can achieve about 40% of normal hair density. Our results could provide the hair surgeon with general information about hair distribution on the Chinese scalp for surgical planning and design in their patients. [source] Impaired EDHF-Mediated Relaxation in Porcine Pulmonary Micro-Arteries by Cold Storage with University of Wisconsin and Euro-Collins SolutionsJOURNAL OF CARDIAC SURGERY, Issue 6 2002Wei Zou Background: Vascular endothelium plays a key role in regulation of vascular tone. Hyperkalemia has been demonstrated to impair the EDHF-mediated endothelial function in coronary circulation. University of Wisconsin (UW) and Eruo-collins (EC) solutions are used for organ preservation in transplantation surgery. The potassium concentration in UW or EC solutions is as high as 125 mmol/L or 115 mmol/L, respectively. This study was designed to examine whether hyperkalemia or storage with UW and EC solutions affects the relaxation mediated by EDHF in the porcine pulmonary micro-arteries. Methods: Porcine pulmonary micro-artery rings (diameter 200,450 ,m) were studied in myograph (n = 8 in each group). After incubation with hyperkalemia (K+ 125 mmol/L, at 37° C), UW or EC solutions (at 4° C for 4 hours), EDHF-mediated relaxation induced by bradykinin (BK, ,10 to ,6.5 log M) in the presence of inhibitors for cyclooxygenase (Indomethacin, 7 ,M), nitric oxide synthase (NG -nitro- L -arginine, 300 ,M), and oxyhemoglobin (20 ,M) was compared with control (Krebs' solution) in precontraction with U46619 (,7.5 log M). Results: The EDHF-mediated relaxation to BK was 69.6 ± 6.3% compared with 97.1 ± 1.7% (p= 0.003) in control (no inhibitors). After incubation with hyperkalemia, the relaxation significantly decreased (38.6 ± 3.0% vs. 59.1 ± 7.4%, p= 0.03). Storage with UW or EC solutions also significantly decreased the relaxation (49.3 ± 7.3% vs. 65.2 ± 3.5%, p= 0.04 and 51.9 ± 8.4% vs. 60.3 ± 6.1%, p= 0.02, respectively). Conclusions: In porcine pulmonary micro-arteries, exposure to hyperkalemia or storage with UW or EC solutions at 4°C for 4 hours impairs the EDHF-mediated endothelial function. The clinical significance of this effect should be further studied. [source] Protection from phototoxic injury during surgery and endoscopy in erythropoietic protoporphyriaLIVER TRANSPLANTATION, Issue 9 2008Staffan Wahlin Erythropoietic protoporphyria is an inherited condition characterized by pronounced solar photosensitivity and in a minority of patients severe liver disease that necessitates liver transplantation for survival. Phototoxic injury to abdominal organs and skin has been reported in several cases of liver transplantation surgery, including a few transplants in which protective light filters were used. This study discusses the optimal characteristics of light filters used during liver transplantation surgery. An experimental model is used to evaluate the relative protection of different filters, and the results are compared with theoretical calculations regarding the risk for phototoxic injury from light sources in health-care procedures. Whether protective measures are warranted in other illuminated procedures besides liver transplantation has been discussed often but never studied. This study elucidates the risk for phototoxic injury in endoscopy, laparoscopy, and non,liver transplant surgery. A theoretical model and epidemiological data are considered. Our findings indicate that endoscopy, laparoscopy, and surgical procedures other than liver transplantation are safe in the noncholestatic protoporphyria patient and that general recommendations for using filters in these situations are not warranted. Among the tested filters, a flexible yellow filter omitting wavelengths below 470 nm is recommended for liver transplant surgery. This filter has been readily accepted by surgeons and offers a good balance between protection and altered visual color perception. The experimental model, using hemolysis of protoporphyrin-loaded erythrocytes as a measure of phototoxicity, has substantiated theoretical findings on relative filter protection. Liver Transpl 14:1340,1346, 2008. © 2008 AASLD. [source] Cyclosporine treatment of RPE allografts in the rabbit subretinal spaceACTA OPHTHALMOLOGICA, Issue 2 2000Sven Crafoord ABSTRACT. Purpose: To determine the effects of systemic cyclosporine A (CsA) on the survival of retinal pigment epithelial (RPE) allografts in the subretinal space in an animal model using atraumatic transplantation surgery. Methods: Following pars plana vitrectomy, an RPE cell suspension from brown rabbits was injected with a glass micropipette into the subretinal space of 39 albino rabbits. For immunosuppression, 22 rabbits were given an injection of CsA, 20 mg daily intramuscularly, 17 rabbits with RPE grafts were controls. The grafts were monitored by biomicroscopy, color fundus photography, and fluorescein angiography. Rabbits were sacrificed at 1, 3 and 6 months, respectively, and the eyes processed for light and electron microscopy including immunohistochemistry. Results: After three months, the transplanted RPE cells, in both the CsA group and the controls, formed a monolayer in the subretinal space. Although a few macrophages were encountered, there was no massive cellular infiltration and the photoreceptor layer was well preserved. After six months, however, there was a disruption of grafted RPE cells in both groups, characterized by dispersion of melanin pigment in the subretinal space, and invasion of macrophages with focal photoreceptor damage but no infiltration of lymphocytes in the retina or choroid. No significant differences between the CsA treated and the control eyes were discernible. Conclusion: Although the subretinal space has been considered an immunologically privileged site, we found that the survival of RPE allografts was limited. CsA did not prevent RPE allograft destruction in the subretinal space. The transplant seems to be disrupted either by immunological mechanisms that are not inhibited by CsA, or by nonimmunologic events. [source] | ||||||||||