Faculty Bibliography

INTRODUCTION: Lymphedema is the chronic swelling of an extremity that occurs commonly after lymph node resection for cancer treatment. Recent studies have demonstrated that transfer of healthy tissues can be used as a means of bypassing damaged lymphatics and ameliorating lymphedema. The purpose of these studies was to investigate the mechanisms that regulate lymphatic regeneration after tissue transfer. METHODS: Nude mice (recipients) underwent 2-mm tail skin excisions that were either left open or repaired with full-thickness skin grafts harvested from donor transgenic mice that expressed green fluorescent protein in all tissues or from LYVE-1 knockout mice. Lymphatic regeneration, expression of VEGF-C, macrophage infiltration, and potential for skin grafting to bypass damaged lymphatics were assessed. RESULTS: Skin grafts healed rapidly and restored lymphatic flow. Lymphatic regeneration occurred beginning at the peripheral edges of the graft, primarily from ingrowth of new lymphatic vessels originating from the recipient mouse. In addition, donor lymphatic vessels appeared to spontaneously re-anastomose with recipient vessels. Patterns of VEGF-C expression and macrophage infiltration were temporally and spatially associated with lymphatic regeneration. When compared to mice treated with excision only, there was a 4-fold decrease in tail volumes, 2.5-fold increase in lymphatic transport by lymphoscintigraphy, 40% decrease in dermal thickness, and 54% decrease in scar index in skin-grafted animals, indicating that tissue transfer could bypass damaged lymphatics and promote rapid lymphatic regeneration. CONCLUSIONS: Our studies suggest that lymphatic regeneration after tissue transfer occurs by ingrowth of lymphatic vessels and spontaneous re-connection of existing lymphatics. This process is temporally and spatially associated with VEGF-C expression and macrophage infiltration. Finally, tissue transfer can be used to bypass damaged lymphatics and promote rapid lymphatic regeneration.

Homeostasis and wound healing rely on stem cells (SCs) whose activity and directed migration are often governed by Wnt signaling. In dissecting how this pathway integrates with the necessary downstream cytoskeletal dynamics, we discovered that GSK3β, a kinase inhibited by Wnt signaling, directly phosphorylates ACF7, a > 500 kDa microtubule-actin crosslinking protein abundant in hair follicle stem cells (HF-SCs). We map ACF7's GSK3β sites to the microtubule-binding domain and show that phosphorylation uncouples ACF7 from microtubules. Phosphorylation-refractile ACF7 rescues overall microtubule architecture, but phosphorylation-constitutive mutants do not. Neither mutant rescues polarized movement, revealing that phospho-regulation must be dynamic. This circuitry is physiologically relevant and depends upon polarized GSK3β inhibition at the migrating front of SCs/progeny streaming from HFs during wound repair. Moreover, only ACF7 and not GSKβ-refractile-ACF7 restore polarized microtubule-growth and SC-migration to ACF7 null skin. Our findings provide insights into how this conserved spectraplakin integrates signaling, cytoskeletal dynamics, and polarized locomotion of somatic SCs.

Fifty-seven adult patients with facial paralysis, who underwent direct muscle neurotisation, were reviewed and divided into three categories depending on the function that direct neurotisation was aiming to augment. Group 1 included 30 patients who underwent direct neurotisation for eye closure and blink, group 2 consisted of 23 patients for smile augmentation, and group 3 comprised 31 patients for depressor. The age of the patients ranged from 21 to 74 years. Denervation time (Dt) ranged from 8 months to 42 years. Eight patients had partial facial paralysis, and 49 patients had complete facial paralysis. The results were based on the functional and electromyography (EMG) scoring of the neurotised muscles showing an overall EMG mean improvement of 26.56% in eye closure, 34.47% in smile restoration and 32.67% in depressor function by the procedure. Median improvement in all facial functions was one grade (25%) in theTerzis grading systems regarding the respective facial functions. The prerequisites are Dt less than 6 months and a functional contralateral facial nerve. In cases where Dt is more than 27 months and preoperative EMG's are silent, a free or pedicled muscle should be used to substitute the denervated native facial muscle. Promoting expressivity and augmenting facial muscle function using direct muscle neurotisation are important components in facial reanimation

BACKGROUND: Occult breast carcinoma is occasionally found in reduction mammaplasty specimens. Historically, these patients were treated with mastectomy because the exact location of the tumor was unknown. Currently, breast conservation is the treatment of choice in 50 to 85 percent of breast cancers. The authors present a technique of routine specimen marking that allows localization of the tumor and preservation of the choice of lumpectomy. METHODS: This is a retrospective review of 866 patients who underwent reduction mammaplasty performed by a single surgeon between 1990 and 2009. Data were collected for patients who had occult cancer found in their specimens, including age, cancer risk factors, abnormality, nodal status, selected treatment, and survival status. Specimens were marked and oriented and then sent in separate bags to the pathologist. RESULTS: There were 10 cases of occult carcinoma among the 866 women (1.15 percent) who underwent reduction mammaplasty. Six cancers were found in patients undergoing reduction for symptomatic macromastia [n = 629 (0.95 percent)]. Four new cancers were found in the group of patients with a personal history of cancer [n = 237 (1.69 percent)]. All 10 patients had normal preoperative mammograms. Location, size, and margin status were easily identified and patients were offered the choice of lumpectomy or mastectomy. CONCLUSIONS: This article demonstrates that careful marking of reduction specimens in high-risk patients or in women older than 40 years allows the pathologist to orient, localize, and further section tissue for margin status. Communication among plastic surgeon, pathologist, oncologist, and radiation therapist preserves the choice of breast conserving therapy for early cancers.

BACKGROUND: This study aimed to assess the efficacy of laparoscopic adjustable gastric banding (LAGB) during a 6-year follow-up period. METHODS: A retrospective database analysis of patients who underwent LAGB at New York University Medical Center between 1 January 2000 and 29 February 2008 was conducted. Patients were included for the efficacy analysis if they were 18 years old or older at the surgery date and had one or more visits with a recorded weight after surgery. Efficacy was assessed using percentage of excess weight loss (%EWL) at 1-year intervals after surgery. Missing weight values were interpolated using a cubic spline function. Linear regression models were used to assess the characteristics that affected the last available %EWL. All patients had implantation of the LAP-BAND system. RESULTS: The inclusion criteria for the efficacy analysis were met by 2,909 patients. The majority of the patients were white (83.3%) and female (68.4%). The mean patient age was 44.6 years, and the mean baseline body mass index (BMI) was 45.3 kg/m2. The %EWL 3 years after surgery was 52.9%, which was sustained thereafter. In multivariate models, increased number of office visits, younger age, female gender, and Caucasian race were significantly associated with a higher maximum %EWL. CONCLUSIONS: The LAP-BAND patients achieved a substantial and sustainable weight loss of approximately 50% at 6 years after surgery

Abstract This article describes the evolution of a computer-aided design/computer-aided manufacturing (CAD/CAM) process where ceramic paste is deposited in a layer-by-layer sequence using a computer numerical control machine to build up core and fixed partial denture (FPD) structures (robocasting). Al(2)O(3) (alumina) or ZrO(2) (Y-TZP) are blended into a 0.8% aqueous solution of ammonium polyacrylate in a ratio of approximately 1:1 solid:liquid. A viscosifying agent, hydroxypropyl methylcellulose, is added to a concentration of 1% in the liquid phase, and then a counter polyelectrolyte is added to gel the slurry. There are two methods for robocasting crown structures (cores or FPD framework). One is for the core to be printed using zirconia ink without support materials, in which the stereolithography (STL) file is inverted (occlusal surface resting on a flat substrate) and built. The second method uses a fugitive material composed of carbon black codeposited with the ceramic material. During the sintering process, the carbon black is removed. There are two key challenges to successful printing of ceramic crowns by the robocasting technique. First is the development of suitable materials for printing, and second is the design of printing patterns for assembly of the complex geometry required for a dental restoration. Robocasting has room for improvement. Current development involves enhancing the automation of nozzle alignment for accurate support material deposition and better fidelity of the occlusal surface. An accompanying effort involves calculation of optimal support structures to yield the best geometric results and minimal material usage

BACKGROUND: Browpexy returns the brow to an anatomical, aesthetically-appealing location on the upper face. Recently, browlifting techniques have evolved from aggressive, open approaches toward less invasive, limited-incision techniques. Browpexy through the upper lid (BUL), an innovative technique based on earlier practices, anchors the underlying brow soft tissue to the bone, allowing for stabilization. Furthermore, this procedure can be performed concomitantly with an upper eyelid blepharoplasty through the same access incision. OBJECTIVE: The authors evaluate the efficacy of BUL in patients with ptotic eyebrows requiring stabilization and/or elevation and in patients with prominent brow fat pads. METHODS: The charts of 21 patients who were treated with BUL by the senior author (HMS) between February 2007 and October 2008 were retrospectively reviewed. RESULTS: The age range of the 21 patients in this study was 54 to 70 years. Twelve patients were men; nine were women. Each patient presented with complaints of tired-appearing or "weighed-down" upper eyelids. All patients were uniformly happy with their postoperative aesthetic results. There were no major immediate or long-term complications (including, but not limited to, uneven postoperative brow position, loss of suspension, frontal nerve injury, hematoma, infection, or wound dehiscence). No patients required reoperation for recurrent brow ptosis or upper lid deformity. CONCLUSIONS: BUL is ideal for patients with ptotic eyebrows who need brow stabilization and/or elevation, as well as for patients with prominent brow fat pads who require stabilization. BUL achieves excellent results through a standard upper eyelid blepharoplasty incision, and allows the surgeon to perform a concomitant upper eyelid blepharoplasty and browpexy without a traditional coronal, scalp, or forehead incision.

BACKGROUND: Flexor tendon injuries are common problems faced by hand surgeons. To minimise the surgical trauma associated with localisation and retrieval of the proximal tendon end, we investigated the use of surgeon-performed ultrasound in the evaluation of injured flexor tendons in a cadaver model. Our goal was to use surgeon-performed ultrasound: (1) to correctly diagnose flexor tendon injuries and (2) to correctly localise the proximal tendon ends within 1cm. METHODS: Flexor tendon injuries with varying degrees of retraction were randomly created in individual digits of cadaver upper extremities, with a number of tendons left uninjured. A surgeon, blinded to the injury status of each digit, imaged each tendon by ultrasound. Predicted injury status of each tendon and localisation of the proximal stump was recorded. A total of 81 tendons were studied. FINDINGS: Correct diagnosis of flexor tendon injury was made in 78 of 81 tendons (96.2% success). Correct localisation of the proximal tendon stump was made in 39 of 50 lacerated tendons (78% success). Small finger injuries were most difficult to assess (66.7% success). With the small finger excluded from our analysis, the localisation success rate increased to 86.8%. The average time taken to image each digit was just under 2.5min. CONCLUSIONS: Surgeon-performed ultrasound evaluation of the hand is a reliable means to diagnose flexor tendon injuries and to accurately localise the proximal tendon ends. This imaging modality may limit the need for extensive surgical exploration during flexor tendon repair. We do not recommend using this technique to image flexor tendon injuries of the small finger at this time