Faculty Bibliography

Perforator flap breast reconstruction is an accepted surgical option for breast cancer patients electing to restore their body image after mastectomy. Since the introduction of the deep inferior epigastric perforator flap, microsurgical techniques have evolved to support a 99 percent success rate for a variety of flaps with donor sites that include the abdomen, buttock, thigh, and trunk. Recent experience highlights the perforator flap as a proven solution for patients who have experienced failed breast implant-based reconstructions or those requiring irradiation. Current trends suggest an application of these techniques in patients previously felt to be unacceptable surgical candidates with a focus on safety, aesthetics, and increased sensitization. Future challenges include the propagation of these reconstructive techniques into the hands of future plastic surgeons with a focus on the development of septocutaneous flaps and vascularized lymph node transfers for the treatment of lymphedema.

The inferior gluteal artery perforator (IGAP) free flap represents an alternative technique for autogenous breast reconstruction in patients with insufficient abdominal donor tissue. Historically, patients underwent a staged approach for bilateral breast reconstruction with the IGAP because it is technically demanding and can be time consuming. The bilateral simultaneous IGAP can be performed effectively with 2 microsurgeons operating together. This is a retrospective study of 22 patients (44 flaps) who underwent bilateral breast reconstruction with bilateral IGAP flaps in one operation between January 2005 and December 2007. The following parameters were evaluated and compared to our published data with unilateral IGAP flap reconstruction: operating time, blood loss, flap weight, hospital length of stay, and perioperative complications. A follow-up patient survey was also conducted to gauge patient's satisfaction with the donor site and procedure. The flap survival rate was 100%. Complications included 1 patient with 1 flap with partial fat necrosis, 2 patients who required reoperation for venous congestion, 1 patient with a hematoma, 2 patients with delayed buttock wound healing, 2 patients requiring resuturing for buttock wound dehiscence, and 1 patient with resolved paresthesias. The majority of patients were satisfied with the procedure and donor site. In this study, we detail our experience with the inferior gluteal region as a reliable source of donor tissue and the simultaneous bilateral IGAP flap as an efficient method of breast reconstruction.

Impaired repair of skin defects is a major complication of diabetes; yet, the pathophysiology of diabetic (db) wound healing remains largely opaque. Here, we investigate the role of humoral factors in modulating db wound repair by generating chimeric animals through parabiotic joining of wild-type (wt) and diabetic (db/db) mice. This strategy allows wounds on healing-deficient db/db mice to be exposed to factors derived from the wt circulation at physiologically appropriate concentrations. When compared with db controls, chimeric db/db animals showed significantly improved healing of full-thickness, cutaneous wounds, with enhanced granulation tissue formation, angiogenesis, cell proliferation, and collagen deposition. Glycemic control was unaffected by parabiosis; however, the distribution of circulating leukocytes, altered in db controls, normalized in db-chimeras. Both wt and db cells were recruited from circulation into db wounds, but wt cells never exceeded 20% of total cells. Improved angiogenesis persisted in db-chimeras separated 24 hours after wounding, suggesting the existence of long-term normalizing factors. This study establishes a new model for studying db wound healing, and shows a key role for circulating factors in normalizing wound repair in diabetes.

Clinical detection of free flap failure lacks sensitivity. Failure is likely accompanied by altered gene expression; however, a genomic approach that identifies potential biomarkers and therapeutic targets has not been described. This study identifies genetic RNA expression alterations via microarray in a free flap failure animal model. A free tissue transfer rat model based on the inferior epigastric vessels was utilized. After microscopic anastomosis, the vein was occluded and RNA extracted from flap tissue of failure and control groups. Gene expression of 3 experimental and control group samples was assessed with the Affymetrix GeneChip Rat 230 v2.0 microarray. Quantitative reverse transcription polymerase chain reaction was performed on RNA of genes identified on an additional 6 experimental and 7 control group flaps. Eight hundred ninety of 28,000 genes had greater than 2-fold expression differences between experimental and controls. Student t test and 2-way analysis of variance filtering with equal variance identified 53 genes with statistically significant differences. Hierarchical clustering by gene ontology identified 4 genes with likely involvement in failure pathogenesis: RT1 class II, locus Bb, secreted frizzled-related protein 1, platelet/endothelial cell adhesion molecule, and Claudin 5. Validation performed by quantitative reverse transcription polymerase chain reaction revealed statistically significant expression alterations in locus Bb, platelet/endothelial cell adhesion molecule, and Claudin 5 of the failure group. Utilizing expression thresholds for test positivity, venous occlusion was predicted with 100% sensitivity and 86% specificity. Three highly sensitive and specific novel genes predictive of flap failure from venous occlusion were identified with altered expression in an animal model.

OBJECTIVE: Determine long-term loss of mandible height with use of stress-shielding reconstruction plates for free fibula flap mandible reconstruction. DESIGN: Retrospective single-blinded medical record review. SUBJECTS: Seventy patients who had fibula free flap mandible reconstructions performed for 10 years. Patients who underwent radiotherapy were excluded. METHODS: Review of 70 fibula free flap mandible reconstructions performed for the last 10 years in a city hospital revealed 7 patients (10%) who had resections for benign odontogenic diseases. All had a three-dimensional cast model made, on which the reconstruction plate was bent to the desired shape preoperatively. Free fibula height on panoramic x-ray images taken preoperatively and at 2 and 12 months postoperatively. RESULTS: Seven (10%) patients met criteria for the study. Bone height was maintained at 2 months postoperatively, but at 12 months, there was a statistically significant loss of fibular bone height averaging 20% in the anterior, body, and ramus areas (P < 0.05). Despite this, all patients were considered eligible for dental rehabilitation, and 4 of 7 patients have had osseointegrated implants placed. CONCLUSIONS: As opposed to miniplates, increased resorption may have been due to the stress-shielding phenomenon unique to a reconstruction plates. However, this did not seem to affect the ability to place osseointegrated implants.

The Allen test is used to diagnose the relative contribution of the ulnar and radial arteries to each hand. We modified this test to investigate the relative vascular contributions to distal perfusion of the lower extremity. With the patient supine, a handheld Doppler is used to locate the first dorsal metatarsal artery. The posterior tibial artery (PT) and dorsalis pedis artery (DP) pulses are compressed. A persistent signal indicates collateral flow through the peroneal artery (PA). Sequential decompression is then used to evaluate the relative contribution of the PT and DP to distal circulation. We report a case in which angiography failed to predict reliance on the PT. In this case, performance of the lower-extremity Allen test (LEAT) led to an alternative recipient vessel choice. The LEAT is simple to perform and provides a valuable adjunct to angiographic data

In this study, we hypothesize that local sustained release of vascular endothelial growth factor (VEGF), using adenovirus vector (ADV)-mediated gene transfer, accelerates experimental wound healing. This hypothesis was tested by determining the specific effects of VEGF(165) application on multiple aspects of the wound healing process, that is, time to complete wound closure and skin biomechanical properties. After showing accelerated wound healing in vivo, we studied the mechanism to explain the findings on multiple aspects of the wound healing cascade, including epithelialization, collagen deposition, and cell migration. Intradermal treatment of wounds in non-obese diabetic and db/db mice with ADV/VEGF(165) improves healing by enhancing tensile stiffness and/or increasing epithelialization and collagen deposition, as well as by decreasing time to wound closure. VEGF(165), in vitro, stimulates the migration of cultured human keratinocytes and fibroblasts, thus revealing a non-angiogenic effect of VEGF on wound closure. In conclusion, ADV/VEGF is effective in accelerating wound closure by stimulating angiogenesis, epithelialization, and collagen deposition. In the future, local administration and sustained, controlled release of VEGF(165) may decrease amputations in patients with diabetic foot ulcers and possibly accelerate closure of venous ulcers and pressure ulcers.Journal of Investigative Dermatology advance online publication, 12 March 2009; doi:10.1038/jid.2009.26

PURPOSE: We examined preoperative factors that could predict successful microdissection testicular sperm extraction in men with azoospermia and nonmosaic Klinefelter's syndrome. We also analyzed the influence of preoperative hormonal therapy on the sperm retrieval rate. MATERIALS AND METHODS: A total of 91 microdissection testicular sperm extraction attempts were done in 68 men with nonmosaic Klinefelter's syndrome. Men with serum testosterone less than 300 ng/dl received medical therapy with aromatase inhibitors, clomiphene or human chorionic gonadotropin before microdissection testicular sperm extraction. Preoperative factors of patient age and endocrinological data were compared in those in whom the procedure was and was not successful. The sperm retrieval rate was the main outcome. Clinical pregnancy (pregnancy with heartbeat) and the live birth rate were also calculated. RESULTS: Testicular spermatozoa were successfully retrieved in 45 men (66%), representing 62 (68%) attempts. Increasing male age was associated with a trend toward a lower sperm retrieval rate (p = 0.05). The various types of preoperative hormonal therapies did not have different sperm retrieval rates but men with normal baseline testosterone had the best sperm retrieval rate of 86%. Patients who required medical therapy and responded to that treatment with a resultant testosterone of 250 ng/dl or higher had a higher sperm retrieval rate than men in whom posttreatment testosterone was less than 250 ng/dl (77% vs 55%). For in vitro fertilization attempts in which sperm were retrieved the clinical pregnancy and live birth rates were 57% and 45%, respectively. CONCLUSIONS: Microdissection testicular sperm extraction is an effective sperm retrieval technique in men with Klinefelter's syndrome. Men with hypogonadism who respond to medical therapy may have a better chance of sperm retrieval.

Genetics gains more and more importance in all areas of health care including craniofacial surgery and dentistry. This does not mean that every patient will benefit from genetic advances, but for many health problems, we will see progress in explaining disease pathogenesis, establishing diagnosis, guiding therapy, predicting prognosis, and achieving prevention. In this report, we briefly review the roles of the PAX9, MSX1, AXIN2, and EDA genes in the causation of congenital tooth agenesis and the promise of molecular genetic research for the improvement of patient care