Faculty Bibliography

PURPOSE/OBJECTIVE:The purpose of this study was to compare the dimensional accuracy, translucency, and biaxial flexural strength of milled zirconia (MZ) versus 3D-printed zirconia (PZ) discs. MATERIALS & METHODS/METHODS:A circular disc measuring 14.0 mm in diameter and 1.20 mm in thickness was designed using computer-aided design (CAD) software. The resulting standard tessellation language (STL) file was used both as a control and to fabricate 36 zirconia (3Y-TZP) disc specimens (n = 36): 18 were milled (group MZ) and 18 were 3D-printed (group PZ). The diameter and thickness of each disc were measured using a digital caliper. Translucency was evaluated using a calibrated dental colorimeter. The flexural strength was determined using the piston-on-three-ball biaxial flexure test. All measurements were done by one blinded examiner. The statistical significance level was set to α = 0.05. RESULTS:The MZ discs had significantly more accurate dimensions than the PZ discs in both diameter and thickness when compared to the control CAD software-designed disc. The MZ discs exhibited significantly higher translucency (translucency parameter (TP) = 16.95 ±0.36 vs. 9.24 ±1.98) and biaxial flexural strength (996.16 ±137.37 MPa vs. 845.75 ±266.16 MPa) than the PZ discs. Finally, MZ possessed a significantly higher Weibull modulus relative to PZ. CONCLUSIONS:The results showed that the milled specimens achieved better dimensional accuracy and were more translucent, stronger, and less prone to failure than printed specimens.

OBJECTIVE:Assess the use of video otoscopy (VO) as a tool for teaching Emergency Department (ED) residents and remote Otolaryngology consultation. STUDY DESIGN/METHODS:Survey and retrospective chart review. SETTING/METHODS:Tertiary care center. METHODS:Emergency Medicine resident physicians completed an otologic skill self-assessment and pathology followed by an interactive training on VO and postintervention assessment after 9 months of use. Outcomes compared change in pre- to posttraining scores. ED consultations using VO during this time period were reviewed to detect differences between the presumed diagnosis/treatment based only on phone consultation and VO image compared to the final diagnosis/treatment after in-person Otolaryngology consultation. RESULTS:Forty-six (63.1%) ED residents participated. Diagnostic accuracy improved by 20.7% overall. The most improved diagnoses were of a normal ear canal (+75%), tympanosclerosis (+58.4%), and ear canal foreign body (+57.1%); most challenging were external auditory canal cyst (-13.6%), hemotympanum (-11.3%), and cerumen (-1.9%). Cholesteatoma did not improve because all responses were incorrect; neither did tympanic membrane perforation because all were correct. Confidence in the otologic exam and anatomy also increased (P < .01). Thirteen consults used VO and 3 (23.1%) had a change in diagnosis/treatment after in-person Otolaryngology evaluation. CONCLUSION/CONCLUSIONS:Training on the use of VO significantly improves the confidence and diagnostic skills of ED providers for many pathologies. This application suggests the efficacy of an otologic e-consultation model.

Nerve growth factor (NGF) monoclonal antibodies inhibit chronic pain, yet failed to gain approval due to worsened joint damage in osteoarthritis patients. We report that neuropilin-1 (NRP1) is a coreceptor for NGF and tropomyosin-related kinase A (TrkA) pain signaling. NRP1 was coexpressed with TrkA in human and mouse nociceptors. NRP1 inhibitors suppressed NGF-stimulated excitation of human and mouse nociceptors and NGF-evoked nociception in mice. NRP1 knockdown inhibited NGF/TrkA signaling, whereas NRP1 overexpression enhanced signaling. NGF bound NRP1 with high affinity and interacted with and chaperoned TrkA from the biosynthetic pathway to the plasma membrane and endosomes, enhancing TrkA signaling. Molecular modeling suggested that the C-terminal R/KXXR/K NGF motif interacts with the extracellular "b" NRP1 domain within a plasma membrane NGF/TrkA/NRP1 of 2:2:2 stoichiometry. G α interacting protein C-terminus 1 (GIPC1), which scaffolds NRP1 and TrkA to myosin VI, colocalized in nociceptors with NRP1/TrkA. GIPC1 knockdown abrogated NGF-evoked excitation of nociceptors and pain-like behavior. Thus, NRP1 is a nociceptor-enriched coreceptor that facilitates NGF/TrkA pain signaling. NRP binds NGF and chaperones TrkA to the plasma membrane and signaling endosomes via the GIPC1 adaptor. NRP1 and GIPC1 antagonism in nociceptors offers a long-awaited nonopioid alternative to systemic antibody NGF sequestration for the treatment of chronic pain.

This study explores the novel application of pyronin Y for fluorescently labeling extracellular matrices (ECMs) and gelatin cryogels, providing a simple and reliable method for laser scanning confocal microscopy. Pyronin Y exhibited remarkable staining ability of the porous structures of gelatin cryogels, indicating its potential as a reliable tool for evaluating such biomaterials. Confocal imaging of pyronin Y-stained cryogels produced high signal-to-noise ratio images suitable for quantifying pores using Fiji/Image J. Importantly, pyronin Y enabled effective dual-color imaging of cryogel-labeled mesenchymal stem cells, expanding its utility beyond traditional RNA assays. Traditional staining methods like Mason's trichrome and Sirius Red have limitations in cryogel applications. Pyronin Y emerges as a powerful alternative due to its water solubility, minimal toxicity, and stability. Our results demonstrate pyronin Y's ability to specifically stain gelatin cryogel's porous structures, surpassing its weak staining of ECMs in 2D. Confocal imaging revealed enduring staining even under rigorous scanning, with no notable photobleaching observed. Furthermore, pyronin Y's combination with Alexa Fluor 647 for dual-color imaging showed promising results, validating its versatility in fluorescence microscopy. In conclusion, this study establishes pyronin Y as a cost-effective and rapid option for fluorescent staining of gelatin cryogels. Its simplicity, efficacy, and compatibility with confocal microscopy make it a valuable tool for characterizing and evaluating gelatin-based biomaterials, contributing significantly to the field of cryogel imaging. The study opens new avenues for dual-color imaging in biomaterial research and tissue engineering, advancing our understanding of cellular interactions within scaffolds. Key features • Fluorescent staining of gelatin-based cryogels with an inexpensive yet less time-consuming protocol. • Pyronin Y staining is suitable for dual-color confocal imaging by combining with far-red fluorophores (such as Alexa Fluor 647). • The method is conducted routinely. Graphical overview Gelatin cryogel staining using pyronin Y.

BACKGROUND/UNASSIGNED:Our objective is to evaluate the utilization fraction (UF) of surgical instruments during a commonly performed ambulatory hand surgery case as an avenue for cost reduction, increased operating room efficiency, and systems quality improvement. METHODS/UNASSIGNED:The total number of instruments opened at the start of the case was recorded followed by instruments being divided into those used and not used during the procedure. Total sterile processing costs were estimated at $1.56 per instrument according to data from our institution's central sterilization processing (CSP) department. RESULTS/UNASSIGNED:Nineteen hand procedures performed by 2 surgeons were included in this study. An average of 120.1 ± 10.9 instruments were opened at the start of each case, while an average of 12.6 ± 5.4 instruments were used per case (Figure 1). This yielded an UF of 10.7% ± 4.8%. Using our internal CSP estimate, we calculated an annual cost of $16 863 to reprocess the current hand tray (Figure 2). Using literature data, this cost ranged from $5 513 to $34 484 annually. The same cost calculations were performed for the theoretical optimized tray (incorporating instruments used at least 20% of the time when opened) containing 23.2 instruments. The annual reprocessing cost of this new tray according to CSP data was $3 260, demonstrating a cost-reduction of $13 603 or 80.7% (Figure 2). CONCLUSIONS/UNASSIGNED:Evaluation of pre- and peri-operative processes is a valuable technique to mitigate increasing healthcare costs and reduce unnecessary healthcare spending, with broad applicability to multiple surgical subspecialties and procedures.

BACKGROUND:The iPhone (Apple Inc, Cupertino, California) contains a high-fidelity 3D-scanner and is widely distributed in the United States. Presently, 3D analysis of the breast necessitates ownership of cost-prohibitive cameras and software packages such as the Vectra system. OBJECTIVES/OBJECTIVE:We compared the accuracy of 3D photos of the breast obtained with the iPhone X 3D scanner against the Canfield Vectra H2 (Canfield Scientific Inc. Parsippany, NJ) in an effort to expand access to 3D technology in plastic surgery. METHODS:Twenty breasts (n=20) were 3D-photographed with iPhone X and the Vectra H2 and compared with color map analysis and by measuring distances across the model between key anatomical landmarks. These distances included sternal notch to nipple (SN-N), mid-chest to nipple (M-N), nipple to mid-inframammary fold (N-IMF), and inframammary fold width (IMF). Statistical tests included the Bland-Altman Plot analysis. RESULTS:When comparing absolute differences in distances between key anatomical landmarks, the average discrepancy in measurements between iPhone and Vectra image pairs were the following: SN-N: 0.94mm, M-N: 0.70mm, N-IMF 0.81mm, and IMF 0.96mm. Colormap analysis demonstrated an average error of 1.53mm, mean of 0.53mm, and standard deviation of ±1.81mm. Bland-Altman Plot revealed a mean difference of 0.13mm and an agreement interval between -1.90 and 2.17mm. CONCLUSIONS:The iPhone is capable of capturing 3D-photographs with a high level of fidelity when compared to Vectra. 3D-scans obtained with the iPhone may be useful for planning nipple position, measuring the breast footprint, choosing implants, and performing other functions using 3D technology that are typically performed using the more expensive systems.

IMPORTANCE/UNASSIGNED:Catastrophic facial injury with globe loss remains a formidable clinical problem with no previous reports of reconstruction by whole eye or combined whole eye and facial transplant. OBJECTIVE/UNASSIGNED:To develop a microsurgical strategy for combined whole eye and facial transplant and describe the clinical findings during the first year following transplant. DESIGN, SETTING, AND PARTICIPANT/UNASSIGNED:A 46-year-old man who sustained a high-voltage electrical injury with catastrophic tissue loss to his face and left globe underwent combined whole eye and face transplant using personalized surgical devices and a novel microsurgical strategy at a specialized center for vascularized composite allotransplantation. MAIN OUTCOMES AND MEASURES/UNASSIGNED:Reperfusion and viability of the whole eye and facial allografts, retinal function, and incidence of acute rejection. RESULTS/UNASSIGNED:The patient underwent a combined whole eye and face transplant from an immunologically compatible donor with primary optic nerve coaptation and conventional postoperative immunosuppression. Globe and retinal perfusion were maintained throughout the immediate postoperative period, evidenced by fluorescein angiography. Optical coherence tomography demonstrated atrophy of inner retinal layers and attenuation and disruption of the ellipsoid zone. Serial electroretinography confirmed retinal responses to light in the transplanted eye. Using structural and functional magnetic resonance imaging, the integrity of the transplanted visual pathways and potential occipital cortical response to light stimulation of the transplanted eye was demonstrated. At 1 year post transplant (postoperative day 366), there was no perception of light in the transplanted eye. CONCLUSIONS AND RELEVANCE/UNASSIGNED:This is the first report of whole eye transplant combined with facial transplant, demonstrating allograft survival including rejection-free graft survival and electroretinographic measurements indicating retinal response to light stimuli. These data highlight the potential for clinical allotransplantation for globe loss.

Large osseous defects resulting from trauma, tumor resection, or fracture render the inherent ability of the body to repair inadequate and necessitate the use of bone grafts to facilitate the recovery of both form and function of the bony defect sites. In the United States alone, a large number of bone graft procedures are performed yearly, making it an essential area of investigation and research. Synthetic grafts represent a potential alterative to autografts due to their patient-specific customizability, but currently lack widespread acceptance in the clinical space. Early in their development, non-autologous bone grafts composed of metals such as stainless steel and titanium alloys were favorable due to their biocompatibility, resistance to corrosion, mechanical strength, and durability. However, since their inception, bioceramics have also evolved as viable alternatives. This review aims to present an overview of the fundamental prerequisites for tissue engineering devices using bioceramics as well as to provide a comprehensive account of their historical usage and significant advancements over time. This review includes a summary of commonly used manufacturing techniques and an evaluation of their use as drug carriers and bioactive coatings-for therapeutic ion/drug release, and potential avenues to further enhance hard tissue regeneration.

Implant-associated bacterial infections are a primary cause of complications in orthopedic implants, and localized drug delivery represents an effective mitigation strategy. Drawing inspiration from the morphology of desiccated soil, our group has developed an advanced drug-delivery system augmented onto titanium (Ti) plates. This system integrates zinc oxide (ZnO) nanorod arrays with a vancomycin drug layer along with a protective Poly(lactic-co-glycolic acid) (PLGA) coating. The binding between the ZnO nanorods and the drug results in attached drug blocks, isolated by desiccation-like cracks, which are then encapsulated by PLGA to enable sustained drug release. Additionally, the release of zinc ions and the generation of reactive oxygen species (ROS) from the ZnO nanorods enhance the antibacterial efficacy. The antibacterial properties of ZnO nanorod-drug-PLGA system have been validated through both in vitro and in vivo studies. Comprehensive investigations were conducted on the impact of bacterial infections on bone defect regeneration and the role of this drug-delivery system in the healing process. Furthermore, the local immune response was analyzed and the immunomodulatory function of the system was demonstrated. Overall, the findings underscore the superior performance of the ZnO nanorod-drug-PLGA system as an efficient and safe approach to combat implant-associated bacterial infections. STATEMENT OF SIGNIFICANCE: Implant-associated bacterial infections pose a significant clinical challenge, particularly in orthopedic procedures. To address this, we developed an innovative ZnO nanorod-drug-PLGA system for local antibiotic delivery on conventional titanium implants. This system is biodegradable and features a unique desiccation-like structure that enables sustained drug release, along with the active substances released from the ZnO nanorods. In a rat calvarial defect model challenged with S. aureus, our system demonstrated remarkable antibacterial efficacy, significantly enhanced bone defect regeneration, and exhibited local immunomodulatory effects that support both infection control and osteogenesis. These breakthrough findings highlight the substantial clinical potential of this novel drug delivery system and introduce a transformative coating strategy to enhance the functionality of traditional metallic biomaterials.