Faculty Bibliography

BACKGROUND:Zygomatic arch (ZA) fractures are a common facial fracture, and reduction is typically performed blind via a Gillies or Keen approach. Postoperative confirmation of reduction thus requires advanced imaging, which may not be readily available in all settings. Thus, there exists a need for an effective, low-cost imaging paradigm to employ in these clinical scenarios. Herein, we introduce the ultrasonic arch reduction (USA Reduction) for ZA fractures. METHODS:All consecutive patients with ZA fractures undergoing a USA Reduction at a single public hospital were reviewed. Patients were operated on by two plastic surgeons. A standard Gillies approach was used in all cases in conjunction with real-time intraoperative ultrasound. All relevant patient data were collected and analyzed. RESULTS:Two patients were included in our study. Patient 1 was a 43-year-old man who was assaulted and sustained a right comminuted zygomatic arch fracture without concomitant trauma. Patient 2 was a 35-year-old man who was hit by a train and sustained a left comminuted ZA fracture in addition to traumatic subarachnoid hemorrhage. Both fractures were successfully reduced under ultrasound guidance in under 1 hour of operating room (OR) time without necessitating the use of postoperative CT. To date, both patients endorse positive postoperative satisfaction with their results. CONCLUSIONS:Intraoperative ultrasound is a safe and effective tool for confirming reduction of ZA fractures in a resource-limited practice while obviating the need for additional radiation. Further investigations to standardize the technique and approach will be useful to optimize this intraoperative adjunct.

PURPOSE/OBJECTIVE:Although many factors in prepectoral breast reconstruction such as mastectomy weight and flap quality are out of the plastic surgeon's control, some elements such as intraoperative tissue expander (TE) fill can be optimized. This study assesses the impact of intraoperative TE fill on postoperative complications in prepectoral breast reconstruction and posits the optimal fill. METHODS:All consecutive, prepectoral TE reconstructions performed between March 2017 and December 2022 at a single center were reviewed. A "fill ratio" or ratio of intraoperative TE fill to mastectomy weight (TEF/MW) was constructed to quantify deadspace in the breast pocket, with values closer to 1 signifying less deadspace. Major complications include those requiring readmission or reoperation and minor complications include those that could be treated as an outpatient. A P < 0.05 was considered statistically significant. RESULTS:A total of 200 patients (318 breasts) with average follow-up of 22 months were included. Patients were, on average, 53 years old, were nonsmoker (98%), were nondiabetic (91%), and had a body mass index of 26 kg/m2. Only immediate reconstructions were included and were performed following prophylactic mastectomies in 34% and therapeutic mastectomies in 66% of cases. Seventy-six (24%) breasts were radiated, and 93 (47%) patients received chemotherapy. Mean mastectomy weight was 546 g, median intraoperative TE fill was 175 ± 250 cc, and median final TE fill was 390 ± 220 cc.Major complications occurred in 64 (20%) breasts and were associated with less deadspace (0.49 vs 0.36, P < 0.05). In multivariable models, a higher fill ratio was associated with 2.4 times higher odds of major complications (95% CI, 1.2-4.7; P = 0.01). Optimal intraoperative TE fill for avoiding major complications was 80 cc, and optimal fill ratio was 0.09.Explantation occurred in 44 (14%) breasts and was associated with less deadspace (0.51 vs 0.35, P < 0.05); the optimal fill for avoiding explantation was 80 cc, and optimal ratio was 0.12. CONCLUSIONS:Higher intraoperative TE fill and less deadspace were associated with postoperative complications. Filling a TE to 80 cc or approximately a tenth of mastectomy weight may reduce complications.

BACKGROUND:The learning curve (LC) is the process of mastering a new technique. This study assesses the LC for robotic-assisted peritoneal flap gender-affirming vaginoplasty (RPGAV). METHODS:A retrospective chart review of all consecutive patients undergoing RPGAV between 09/2017 and 02/2023 at a single center was performed. Operative times (OT) were analyzed to describe the LC. A cutoff point was determined after which OT stabilized, and this was used to compare perioperative and postoperative outcomes. RESULTS:Five hundred RPGAVs were performed. Median OT was 125 (interquartile range 105-181) minutes and decreased significantly over time. The minimum number of cases required to observe a plateau in OT is 300 patients.After adjusting for the LC, 2 variables significantly affected OT: a 1-point increase in body mass index increased OT by 1.4 minutes [95% confidence interval (1.0, 1.9), P < 0.001] and the single port robot decreased OT by 34 minutes [95% CI 1 (-43.1, -25.0), P < 0.001] as compared to the traditional multiport Xi robot.When comparing the first 300 cases (learning phase) to the last 200 (expert phase), length of stay, blood transfusions, and rates of elective revision surgery were lower in the expert phase. CONCLUSIONS:The LC for RPGAV in this large cohort was 300 cases. Patient body mass index causes a dose-response increase in OT and the single port robot dramatically decreases OT. Although OT is just one facet of overall efficiency, differences between learning and expert phases are evident in decreased length of stay, transfusions, and rates of revision surgery.

GENERAL PURPOSE/OBJECTIVE:To provide an evidence-based review of strategies for the prevention and management of wounds and postoperative scars following microsurgical autologous breast reconstruction. TARGET AUDIENCE/BACKGROUND:This continuing education activity is intended for physicians, physician assistants, nurse practitioners, and registered nurses with an interest in skin and wound care. LEARNING OBJECTIVES/OUTCOMES/OBJECTIVE:After participating in this educational activity, the participant will: 1. Identify operative considerations to promote wound healing in microsurgical autologous breast reconstruction. 2. Synthesize management strategies for major flap complications following microsurgical autologous breast reconstruction. 3. Explain features in the assessment, prevention, and treatment of scars following microsurgical autologous breast reconstruction.

This preclinical, in vivo study aimed to histologically and histomorphometrically evaluate the effect of implant design features on bone healing during the early stages of osseointegration. Three different implant macrogeometries and surface treatments were evaluated: (1) trapezoidal threads with decompressing vertical chambers and blasted acid-etched surface (Maestro/Blasted+AE); (2) large thread pitch implant with deep and wide threads, with TiUnite surface (RS/TiUnite); and (3) progressive buttress threads with SLActive surface (BL/SLActive). Implant surfaces were characterized by scanning electron microscopy, profilometry, and energy-dispersive X-ray spectroscopy. Implants were placed in the iliac bone of 12 female sheep (~65 kg and 2 years old). Following healing times of 3- and 6- weeks, samples were harvested and subjected to qualitative and quantitative histological/histomorphometric evaluations. Percentages of bone-to-implant contact (%BIC) along the implant's perimeter and bone area fraction occupancy (%BAFO) within implant threads were measured, and results were analyzed using a linear mixed model analysis. All implants, irrespective of differences in macrogeometry and surface treatment, at both healing times demonstrated successful osseointegration. Evaluations of %BIC yielded no statistically significant differences among groups at 3 and 6 weeks (p > 0.052). While no significant differences were detected among groups for %BAFO at 3 weeks (p > 0.249), Maestro/Blasted+AE yielded significantly higher degrees of bone formation within implant threads relative to RS/TiUnite (p = 0.043) and BL/SLActive group (p = 0.032) at the 6-week time point. Qualitative histological analyses depicted different osseointegration features for the different implants. While Maestro/Blasted+AE portrayed evidence of an intramembranous-like osseointegration pathway in the healing chambers and interfacial remodeling at thread tips, BL/SLActive and RS/TiUnite groups predominantly presented an interfacial bone remodeling healing pathway. Implant design features influenced the osseointegration pathway, where implants with decompressing vertical chambers enhanced bone formation between implant threads.

Aging populations worldwide face an increasing burden of age-related chronic conditions, necessitating a deeper understanding of the underlying mechanisms. Purine metabolism has emerged as a crucial player in the pathophysiology of aging, affecting various tissues and organs. Dysregulation of purine metabolism, particularly alterations in extracellular adenosine levels and adenosine receptor signaling, contributes to age-related musculoskeletal problems, cardiovascular diseases, inflammation, and impaired immune responses. Changes in purine metabolism are associated with diminished tissue repair and regeneration, altered bone density, and impaired muscle regeneration. Mechanistically, age-related alterations in purine metabolism involve reductions in extracellular adenosine production, impaired autocrine signaling, and dysregulated expression of CD73 and CD39. Targeting adenosine receptors, such as A_2A and A_2B receptors, emerges as a promising therapeutic approach to mitigate age-related conditions, including sarcopenia, obesity, osteoarthritis, and impaired wound healing. Since we cannot reverse time, understanding the intricate molecular interplay between purine metabolism and aging-related pathologies holds significant potential for developing novel therapeutic strategies to improve the health and quality of life of aging populations. In this review, we compile the findings related to purine metabolism during aging in several tissues and organs and provide insights into how these signals can be manipulated to circumvent the deleterious effects of the passage of time on our body.

BACKGROUND:The National Comprehensive Cancer Network guidelines consider pancreatic cancer with celiac axis (CA), proper hepatic artery (PHA), and superior mesenteric artery (SMA) involvement unresectable. Thus, technical reports and video illustrations of these operations are rare. We report the stepwise management of multivascular reconstruction for Mayo Clinic class IIIb CA resections at New York University Langone Health, a dedicated center of excellence in pancreatic surgery. METHODS:We illustrated the management of a 56-year-old patient with biopsy-confirmed pancreatic ductal adenocarcinoma arising from the pancreatic body and involving the CA, PHA, SMA, and mesentericoportal venous axis. PERIOPERATIVE MANAGEMENT/UNASSIGNED:The preoperative stepwise considerations include: 1) mandatory patient selection; 2) planning vascular reconstructability; 3) tailoring risk assessment while carefully considering the need for total pancreatectomy, total gastrectomy, and mesenteric/hepatic revascularization; and 4) 3D-reconstruction for arterial evaluation. The key intraoperative considerations include: 1) selective and sequential clamping for vascular reconstruction in a "domino" fashion, to minimize warm ischemic time 2) a combined multi-surgeon approach to comprehensively tackle vascular reconstructions; 3) a low threshold for total pancreatectomy to avoid pancreatic leak; and 4) two-stage surgery to reassess the blood supply to the liver and stomach for on-demand gastric preservation instead of a theoretically advised total gastrectomy. CONCLUSION/CONCLUSIONS:Liver, stomach, and bowel vascularization present life-threatening risks that require an extensive preoperative evaluation and a multidisciplinary approach. Our stepwise management for these extensive operations includes total pancreatectomy, "domino" vascular reconstruction, and two-stage surgery.

OBJECTIVES/OBJECTIVE:To characterize two experimental zirconia bilayer materials compared to their monolithic controls, before and after hydrothermal aging. METHODS:Commercial zirconia powders were utilized to fabricate two bilayer materials: 3Y-TZP+ 5Y-PSZ (3Y+5Y/BI) and 4Y-PSZ+ 5Y-PSZ (4Y+5Y/BI), alongside control groups 3Y-TZP (3Y/C), 4Y-PSZ (4Y/C), and 5Y-PSZ (5Y/C). Compacted specimens were sintered (1550 °C- 2 h, 3 °C/min), and half of them underwent hydrothermal aging (134 °C-20h, 2.2 bar). Characterizations were performed through scanning-electron microscopy (SEM), X-ray diffraction (XRD), Raman spectroscopy, reflectance tests and biaxial flexural strength test (ISO:6872). Weibull statistics were applied to determine the characteristic strength and Weibull modulus. Grain size and optical properties were analyzed using two-way ANOVA followed by the Tukey test. RESULTS:Degradation regions and monoclinic phase were observed at aged 3Y-TZP and 4Y-PSZ surfaces. Significant differences were observed in the evaluation of optical properties between the bilayer and control groups. The bilayer materials presented intermediate characteristic strength values compared to their controls and aging significantly increased the strength of some groups. SIGNIFICANCE/CONCLUSIONS:Experimental bilayer materials presented lower mechanical properties than monolithic controls, 3Y/C and 4Y/C. Hydrothermal aging increased the characteristic strength of bilayered and monolithic controls, except for 5Y-PSZ. Both experimental bilayer systems, as well as monolithic controls, met the ISO 6872:2015 requirements for single-unit crowns (100 MPa), 3-unit fixed dental prostheses (FDPs) up to premolars (300 MPa), and 3-unit FDPs involving molars (500 MPa). However, for FDPs with four or more units, only monolithic 3Y-TZP and 4Y-PSZ, and bilayered 3Y+5Y met the required minimum flexural strength (≥800 MPa).

OBJECTIVE:To synthesize bilayer zirconia systems based on commercial or recycled 3Y-TZP obtained from non-milled remnants and to compare their optical and mechanical properties before and after aging. METHODS:Bilayer zirconia samples were fabricated using either recycled 3Y-TZP (3Y-R/4Y and 3Y-R/5Y) or commercial powders (3Y/4Y and 3Y/5Y). Microstructure and phase composition were analyzed using ScanningElectronMicroscopy (SEM) and X-Ray Diffraction (XRD). Optical and mechanical properties were assessed via reflectance and biaxial flexural strength tests (BFS), followed by fractographic analysis. Optical properties and BFS data were analyzed using two-way ANOVA and Tukey test, and Weibull statistics, respectively. RESULTS:Recycled powder exhibited particle sizes < 2.07μm. SEM micrographs depicted dense surfaces with largest grains in the 5Y, followed by recycled-3Y, 4Y, and commercial-3Y. XRD analysis revealed tetragonal peaks in commercial and recycled 3Y-TZPs, and tetragonal and cubic phases in the 4Y and 5Y surfaces. Aging induced significant phase transformation in 4Y (∼40 %), commercial- (58 %) and recycled-3Y (53 %), with no effect in 5Y surfaces. Commercial bilayers exhibited higher translucency and strength (∼1130 MPa) compared to recycled bilayers (∼935 MPa), with no significant differences within commercial, nor within recycled groups. Aging decreased contrast ratio for recycled groups and increased the strength of all groups. While all groups presented high reliability up to 500MPa, commercial bilayers outperformed recycled systems at 800-MPa. SIGNIFICANCE/CONCLUSIONS:The synthesis of bilayered systems using recycled-3Y was successful, resulting in high reliability in missions up to 500MPa. Bilayers based on commercial powder demonstrated superior translucency, strength, and reliability at 800MPa compared to their recycled counterparts.