The Role of Augmented Reality in the Next Phase of Surgical Education.

Concomitant with such a shift toward competency-based curricula, there has been increasing adoption of surgical simulation coupled with virtual, mixed, and augmented reality. These technologies have become more commonplace across multiple surgical disciplines, in domains such as preoperative planning, surgical education, and intraoperative navigation. However, there is a relative paucity of literature pertaining to the application of this technology to plastic surgery education. This review outlines the advantages of mixed and augmented reality in the pursuit of an ideal simulation environment, their benefits for the education of plastic surgery trainees, and their role in standardized assessments. In addition, we offer practical solutions to commonly encountered problems with this technology. Augmented reality has tremendous untapped potential in the next phase of plastic surgery education, and we outline steps toward broader implementation to enhance the learning environment for our trainees and to improve patient outcomes.

An Algorithmic Approach to the Treatment of Kienböck Disease.

The algorithm and rationale described is a reflection of our own surgical experience for this challenging disorder and can be compared with other publications. Our algorithm has evolved from treatment of a large volume of patients with Kienböck disease in a referral practice. However, it is limited to the management that we have found logical, effective, and within our scope of experience. The treatment guidelines for our specialty as a whole will evolve as our understanding of the etiology and our ability to quantify efficacy improves.

Bilateral Preiser Disease in a Patient with Sickle Cell Anemia.

Preiser disease is a rare condition of avascular necrosis of the scaphoid occurring in the absence scaphoid fracture or trauma. While the etiology of Preiser disease remains unknown, it has been associated with steroid use, chemotherapy, and infrequently with systemic diseases. No reports have associated Preiser disease with hemoglobinopathy. Due to the rarity of Preiser disease, management remains controversial and evidence is limited. Here, we describe the case of a 32-year-old right-hand dominant male with sickle cell anemia and a 4-year history of bilateral wrist pain. Radiographs and gadolinium-enhanced magnetic resonance imaging revealed bilateral Preiser disease. He was successfully managed with a 1,2 intercompartmental supraretinicaular artery vascularized bone graft to the right scaphoid.

Effectiveness of Platelet-Rich Plasma Injections for Nonsurgical Management of Carpal Tunnel Syndrome: A Systematic Review and Meta-analysis of Randomized Controlled Trials.

OBJECTIVE: To systematically review and evaluate the efficacy and complication profile of platelet-rich plasma (PRP) injection into the carpal tunnel for management of carpal tunnel syndrome (CTS). DATA SOURCES: PubMed, MEDLINE, SCOPUS, EMBASE, Google Scholar, Cochrane Central Register of Controlled Trials, and Web of Sciences (from inception to January 1, 2019). STUDY SELECTION: Controlled trials addressing PRP for CTS. DATA EXTRACTION: Two reviewers independently screened the titles, abstracts, and full texts, extracting data from eligible studies. The outcomes of interest were the visual analog score (VAS) for pain and the Boston Carpal Tunnel Questionnaire (BCTQ), including the subscales of the symptom severity scale (SSS) and the Functional Status Scale (FSS). Other reported outcome measures and complications were analyzed descriptively. DATA SYNTHESIS: Four randomized controlled studies satisfied the inclusion criteria and analyzed a total of 191 cases with a final follow-up of either 3 or 6 months. Control groups included splinting in 2 studies, corticosteroid injection in 1 study, and saline injection in 1 study. There was a statistically and clinically significant improvement in the BCTQ (standardized mean difference=-2.06; 95% confidence interval [CI], -3.41 to -0.70; P=.003) between groups. Subgroup analysis showed significant improvement in SSS (standardized mean difference=-1.95; 95% CI, -3.65 to -0.25; P=.02) but not for FSS (standardized mean difference=-2.19; 95% CI, -4.77 to 0.40; P=.10). There was a similar improvement in VAS and nerve conduction studies in those receiving PRP compared to controls. Complication rate in the included studies was low with 4 of 97 participants receiving PRP injections experiencing transient pruritis, burning, or tingling. CONCLUSIONS: PRP represents a promising therapy for patients with mild to moderate CTS; however, included studies were limited as follow-up was short, the studies included patients that were heterogeneous, and the number of included studies was low. Further investigation is necessary to determine the true efficacy and effect of PRP and to better delineate the long-term results in patients with CTS.

Treatment of neurotrophic keratopathy with minimally invasive corneal neurotisation: long-term clinical outcomes and evidence of corneal reinnervation.

AIM: To report clinical outcomes and evidence of corneal innervation in patients with neurotrophic keratopathy (NK) treated with minimally invasive corneal neurotisation (MICN) using a sural nerve graft and donor sensory nerves from the face. METHODS: Patients undergoing MICN at The Hospital for Sick Children, Toronto, Canada were prospectively recruited. Data on central corneal sensation (CCS, measured with Cochet-Bonnet aesthesiometer), best-corrected visual acuity (BCVA) and corneal epithelial integrity were collected. In four patients who subsequently underwent keratoplasty, immunohistochemical analysis was performed on the corneal explants. One patient underwent magnetoencephalography (MEG) after MICN to characterise the neurophysiological pathways involved. RESULTS: Between November 2012 and February 2017, 19 eyes of 16 patients underwent MICN. Mean follow-up was 24.0±16.1 months (range, 6-53). Mean CCS significantly improved from 0.8±2.5 mm to 49.7±15.5 mm at final follow-up (p<0.001). Mean BCVA remained stable, and the number of episodes of corneal epithelial defects after MICN was significantly reduced compared with the year leading up to the procedure (21% vs 89%, respectively; p<0.0001). In the four eyes that underwent keratoplasties after MICN, all transplants fully re-epithelialised and regained sensation subsequently. Immunohistochemistry of the corneal explants demonstrated evidence of corneal reinnervation. In one patient who was 8 months after MICN, novel neuroactivity was detected on MEG in the ipsilateral somatosensory cortex on mechanical stimulation of the reinnervated cornea. CONCLUSIONS: By providing an alternative source of innervation, MICN improves corneal sensation and stabilises the corneal epithelium, permitting optical keratoplasty for patients with NK-related corneal opacity.

Sensory and functional morbidity following sural nerve harvest in paediatric patients.

BACKGROUND: The sural nerve is a common donor site for nerve reconstruction. The only study describing outcomes in paediatric patients was following bilateral sural nerve harvest before the age of 1 year. Bilateral nerve harvest at such a young age may limit patients' ability to perceive a sensory difference. The objective of this study was to understand the sensory and functional deficit after unilateral sural nerve harvest in paediatric patients. METHODS: A prospective case series was performed in children (age 6-18 years) following unilateral sural nerve harvest. The contralateral foot was used as a control. Sensory Threshold Evaluation was performed by Weinstein Enhanced Sensory Test (WEST) - Foot, and a Functional Sensory and Pain Questionnaire was administered. Sural nerve harvest was performed by a minimally invasive technique using a nerve stripper. RESULTS: Twenty-eight feet of 14 patients that underwent unilateral sural nerve harvest were assessed. As a group, the 14 feet with sural nerve harvest demonstrated significantly higher thresholds in the four areas tested (p <0.05), thus identifying objective sensory loss at each location. The location of sensory loss in each patient was variable, with heavier sensory thresholds detected in 69.6% of areas tested than those in the corresponding location in the contralateral foot. Greater sensory loss was detected at the proximal lateral foot than at the distal lateral foot. Responses to the questionnaire revealed that only one patient perceived a sensory loss that affected their function. CONCLUSIONS: Unilateral sural nerve harvest in paediatric patients resulted in measurable sensory loss. Despite loss of innervation, only two patients reported intermittent dysaesthesia or cold sensitivity, and the majority of the patients reported no functional deficit.

Corneal Neurotization Improves Ocular Surface Health in a Novel Rat Model of Neurotrophic Keratopathy and Corneal Neurotization.

Purpose: Corneal neurotization is a novel surgical procedure to reinnervate the cornea in patients with neurotrophic keratopathy (NK). We developed a rat model of NK and corneal neurotization to further investigate corneal neurotization as a treatment to improve maintenance and healing of the corneal epithelium. Methods: Thy1-GFP+ Sprague Dawley rats were used to develop the model. Corneal denervation was performed via stereotactic electrocautery of the ophthalmomaxillary branch of the trigeminal nerve. Corneal neurotization was performed by guiding donor sensory axons from the contralateral infraorbital nerve into the cornea via two nerve grafts. Corneal imaging, including nerve density measurements and retrograde labeling were performed to validate the model. In vivo assays of corneal maintenance and repair were used to examine whether treatment with corneal neurotization improved healing in rats with NK. Results: Corneal neurotization significantly increased corneal axon density in rats with NK (P < 0.01). Retrograde labeling of the cornea in rats with corneal neurotization labeled 206 ± 82 neurons in the contralateral trigeminal ganglion, confirming axons reinnervating the cornea derived from the contralateral infraorbital nerve. Corneal reinnervation after corneal neurotization improved corneal epithelial maintenance and corneal healing after injury (P < 0.01). Conclusions: Donor nerve fibers reinnervate the insensate cornea after corneal neurotization and significantly improve corneal maintenance and repair. This model can be used to further investigate how corneal neurotization influences epithelial maintenance and repair in the context of NK.

Outcomes following coronary artery bypass grafting with microsurgery in paediatric patients.

OBJECTIVES: Paediatric coronary artery bypass grafting is indicated in cases of clinically significant and symptomatic coronary stenosis, with frequent complications occurring in the perioperative period. To reduce complications and improve outcomes of these procedures, surgical microscopes have been used at our centre with the anastomosis performed by a microvascular surgeon. The purpose of this article is to report our institutional experience in all patients who have undergone paediatric coronary artery bypass grafting procedures with and without microvascular techniques. METHODS: Twenty-four patients who underwent coronary artery bypass grafting from January 2000 to May 2017 were retrospectively reviewed. RESULTS: Eighteen patients underwent bypass without microvascular involvement and 6 patients required the use of microsurgical techniques. Median age at the time of operation was 9.79 and 2.02 years for the 2 groups, respectively. The median weight at the time of operation was 41.2 and 10.75 kg for the 2 groups, respectively. Procedures were performed emergently in 4 patients. Three major anastomotic complications occurred requiring reoperation, although none occurred in the microvascular group. The median follow-up was 3.40 years and 5.25 years for the 2 groups, respectively. Three patients were symptomatic at last follow-up and 2 deaths occurred, all in the non-microvascular group. All grafts were patent in both groups. There were no statistically significant differences between preoperative and postoperative ejection fraction between the groups. CONCLUSIONS: Our results highlight the potential positive impact of collaboration between cardiac and microvascular surgeons during paediatric coronary artery bypass grafting procedures and the subsequent reduction in complications that may be expected.

In Vivo Confocal Microscopy Reveals Corneal Reinnervation After Treatment of Neurotrophic Keratopathy With Corneal Neurotization.

PURPOSE: To document the presence and location of new sensory nerve fibers after corneal neurotization using in vivo confocal microscopy (IVCM) in 2 patients with neurotrophic keratopathy (NK). METHODS: Two patients with unilateral advanced NK received corneal neurotization to surgically reinnervate the cornea. IVCM was used to identify subbasal nerve fibers and document corneal reinnervation. In 1 patient (case 1), IVCM was performed before and after corneal neurotization; in the second patient (case 2), IVCM was performed after neurotization and corneal transplantation. RESULTS: In case 1, who had hand motion visual acuity due to NK-associated corneal perforation that necessitated cyanoacrylate gluing, preoperative IVCM identified no subbasal nerves; however, subbasal nerves were identified 6 months after corneal neurotization, and there were no further episodes of persistent epithelial defects. In case 2, in whom NK with a total absence of corneal sensation was the result of treated basal skull meningioma, corneal sensation, visual acuity, and ocular surface health improved after corneal neurotization. Deep anterior lamellar keratoplasty was performed 2.5 years after corneal sensation was reestablished. IVCM demonstrated corneal reinnervation at the stromal and subbasal level in a pattern different from the normal cornea. CONCLUSIONS: Corneal neurotization restores corneal sensation by reinnervating the stromal and subbasal layers of the cornea. In doing so, corneal neurotization may halt the process of NK and prevent further visual loss.

N-Acetylcysteine Prevents Retrograde Motor Neuron Death after Neonatal Peripheral Nerve Injury.

BACKGROUND: Neuronal death may be an overlooked and unaddressed component of disability following neonatal nerve injuries, such as obstetric brachial plexus injury. N-acetylcysteine and acetyl-L-carnitine improve survival of neurons after adult nerve injury, but it is unknown whether they improve survival after neonatal injury, when neurons are most susceptible to retrograde neuronal death. The authors' objective was to examine whether N-acetylcysteine or acetyl-L-carnitine treatment improves survival of neonatal motor or sensory neurons in a rat model of neonatal nerve injury. METHODS: Rat pups received either a sciatic nerve crush or transection injury at postnatal day 3 and were then randomized to receive either intraperitoneal vehicle (5% dextrose), N-acetylcysteine (750 mg/kg), or acetyl-L-carnitine (300 mg/kg) once or twice daily. Four weeks after injury, surviving neurons were retrograde-labeled with 4% Fluoro-Gold. The lumbar spinal cord and L4/L5 dorsal root ganglia were then harvested and sectioned to count surviving motor and sensory neurons. RESULTS: Transection and crush injuries resulted in significant motor and sensory neuron loss, with transection injury resulting in significantly less neuron survival. High-dose N-acetylcysteine (750 mg/kg twice daily) significantly increased motor neuron survival after neonatal sciatic nerve crush and transection injury. Neither N-acetylcysteine nor acetyl-L-carnitine treatment improved sensory neuron survival. CONCLUSIONS: Proximal neonatal nerve injuries, such as obstetric brachial plexus injury, produce significant retrograde neuronal death after injury. High-dose N-acetylcysteine significantly increases motor neuron survival, which may improve functional outcomes after obstetrical brachial plexus injury.

Cross-Face Nerve Grafting with Infraorbital Nerve Pathway Protection: Anatomic and Histomorphometric Feasibility Study.

Smiling is an important aspect of emotional expression and social interaction, leaving facial palsy patients with impaired social functioning and decreased overall quality of life. Although there are several techniques available for facial reanimation, staged facial reanimation using donor nerve branches from the contralateral, functioning facial nerve connected to a cross-face nerve graft (CFNG) is the only technique that can reliably reproduce an emotionally spontaneous smile. Although CFNGs provide spontaneity, they typically produce less smile excursion than when the subsequent free functioning muscle flap is innervated with the motor nerve to the masseter muscle. This may be explained in part by the larger number of donor motor axons when using the masseter nerve, as studies have shown that only 20% to 50% of facial nerve donor axons successfully cross the nerve graft to innervate their targets. As demonstrated in our animal studies, increasing the number of donor axons that grow into and traverse the CFNG to innervate the free muscle transfer increases muscle movement, and this phenomenon may provide patients with the benefit of improved smile excursion. We have previously shown in animal studies that sensory nerves, when coapted to a nerve graft, improve axonal growth through the nerve graft and improve muscle excursion. Here, we describe the feasibility of and our experience in translating these results clinically by coapting the distal portion of the CFNG to branches of the infraorbital nerve.

Painful pediatric traumatic neuroma: surgical management and clinical outcomes.

PURPOSE: Painful neuromas can limit function and decrease quality of life. Although management of traumatic neuromas in adults is well represented in the literature, traumatic neuromas are seen less frequently in children and adolescents, and their management is underrepresented in the literature. We present a sample of our clinical experience with painful pediatric neuromas and describe the surgical management and clinical outcomes of these cases. METHODS: A retrospective case review was conducted on patients treated at our pediatric tertiary care center. The same surgeon was responsible for management and follow-up of all patients. RESULTS: The sample of five patients was 60 % female and had a mean age of 12.2 (3-16) years. Each case was managed using a different surgical technique. All the patients had acceptable outcomes with a mean post-operative pain score of 0.4 (0-2) out of 10 and no residual functional outcomes. CONCLUSIONS: It is important for clinicians to recognize that pediatric patients develop painful neuromas following nerve trauma and to understand the neurophysiologic basis for their management. Our report demonstrates that many of the techniques that we use for neuroma repair in adults are applicable in the pediatric population.

Retrograde labeling of regenerating motor and sensory neurons using silicone caps.

BACKGROUND: Retrograde labeling permits the investigation of the number, distribution and axonal projections of neurons in the peripheral nervous system. The well technique for labeling peripheral nerves consists of incubating the exposed peripheral nerve in a well for one hour, a time intensive technique. However, other techniques that inject tracers directly into the nerve or muscle may result in variable labeling depending on nerve preparation and location of injection. NEW METHOD: We describe a method of retrograde labeling peripheral nerves that increases tracer uptake and improves labeling efficiency. This technique utilizes a silicone cap over the nerve that is kept in place with fibrin glue, permitting closure of the incision with the cap in place, mitigating the need to wait one hour for back-labeling as with the standard well technique. RESULTS: In the rat common peroneal nerve, the new silicone cap technique, compared to the standard well technique, labeled 405±11 (SEM) vs. 378±21 motoneurons and 953±40 vs. 948±57 sensory neurons. These counts were not statistically different. Labeling intensity was greater in DRG neurons with the silicone cap technique, but this difference was not evident in motoneurons. COMPARISON WITH EXISTING METHOD: Retrograde-labeling with silicone caps labels an equal number of motor and sensory neurons in comparison with the standard well technique and labels sensory neurons with greater intensity. CONCLUSIONS: Retrograde-labeling with silicone caps reliably labels neurons and significantly decreases the time required for labeling, reducing anesthetic exposure and improving the efficiency of the technique.

Serial estimation of motor unit numbers using an implantable system following nerve injury and repair in rats.

Motor unit number estimation (MUNE) is an established technique to assess recovery following peripheral nerve injury. In rats, where the vast majority of peripheral nerve research is conducted, assessing motor units at various time points requires a terminal procedure due to the invasive nature of current techniques. Here, we present an implanted system that was used to serially assess MUNE after peripheral nerve injury and repair in rats. This system significantly increases the efficiency of peripheral nerve research by negating the need for terminal procedures, allowing for serial MUNE assessment over time in the same rat. Our system utilizes a commercial implantable stimulator, custom designed cuff electrode, and corresponding custom software with automatic M-wave classification to quickly assess functional reinnervation up to 8 weeks following nerve injury and repair. The concepts presented in this paper are applicable to any implanted device with a transcutaneous radio frequency or inductive link that can be used to trigger nerve stimulation. The methodology is also applicable to researchers without access to implantable devices.

Restoration of Trigeminal Cutaneous Sensation with Cross-Face Sural Nerve Grafts: A Novel Approach to Facial Sensory Rehabilitation.

UNLABELLED: Although treating facial palsy is considered debilitating for patients, trigeminal nerve palsy and sensory deficits of the face are overlooked components of disability. Complete anesthesia leaves patients susceptible to occult injury, and facial sensation is an important component of interaction and activities of daily living. Sensory reconstruction is well established in the restoration of hand sensation; however, only one previous report proposed a surgical strategy for sensory nerve reconstruction of the face with use of nerve transfers. Nerve transfers, when used alone, have limited application because of their restricted arc of rotation in the face; extending their arc by adding nerve grafts greatly expands their utility. The following cases demonstrate the early results after V2 and V3 reconstruction with cross-face nerve grafts in three patients with acquired trigeminal nerve palsy. Cross-face nerve grafts using the sural nerve permit more proximal reconstruction of the infraorbital and mental nerves, which allows reinnervation of their entire cutaneous distribution. All patients demonstrated improved sensation in the reconstructed dermatomes, and no patients reported donor-site abnormalities. Cross-face nerve grafts result in minimal donor-site morbidity and are promising as a surgical strategy to address sensory deficits of the face. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, V.

A new system for severity scoring of facial fractures: development and validation.

Facial fractures are often the result of high-velocity trauma, causing skeletal disruption affecting multiple anatomic sites to varying degrees. Although several widely accepted classification systems exist, these are mostly region-specific and differ in the classification criteria used, making it impossible to uniformly and comprehensively document facial fracture patterns. Furthermore, a widely accepted system that is able to provide a final summary measure of fracture severity does not exist, making it difficult to investigate the epidemiologic data surrounding facial fracture severity. In this study, a comprehensive method for panfacial fracture documentation and severity measurement is proposed and validated through a retrospective analysis of 63 patients operated on for acute facial fracture. The severity scale was validated through statistical analysis of correlation with surrogate markers of severity (operating room procedure time and number of implants). Spearman correlation coefficients were calculated, and a statistically significant correlation was found between severity score and both number of implants and operating room procedure time (R = 0.92790 and R = 0.68157, respectively). Intraclass correlation coefficients were calculated to assess intrarater and interrater reliabilities of the severity scale and were found to be high (0.97 and 0.99, respectively). This severity scale provides a valuable, validated research tool for the investigation of facial fracture severity across patient populations, allowing for systematic evaluation of facial fracture outcomes, cost-benefit analysis, and objective analysis of the effect of specific interventions.

Elevating the role of medical informational officer.

Consider the reasons why a chief medical informatics officer should be part of the senior management team of a health care organization.