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Background Well-defined, simple surgical models are useful in translational research in that they provide real world scenarios to evaluate novel technologies. Open porcine thyroidectomy has been used for several decades as a model to study nerve injury in thyroid surgery, but published anatomic descriptions are many decades old. In recent years, experience in robotic thyroidectomy surgery has led to refinements in approach and technique in humans. We present a contemporary review of porcine thyroidectomy with a novel description of an open robotic surgical approach. Methods Porcine cadaveric anatomy study. Results The porcine infrahyoid musculature is comparable to humans. The primary arterial supply to the thyroid gland comes from the thyroid artery, a branch of the omocervical artery. Thyroid veins can also be identified bilaterally. There is a single thyroid lobe located anterior to the trachea with two parathyroid glands. Open robotic thyroidectomy is described using two instruments (grasping forceps and monopolar cautery) and standardized surgical steps are defined. Dissection around the thyroid parenchyma requires mobilization of prominent thymus tissue. The recurrent laryngeal nerve in the tracheoesophageal groove is separate from the thyroid parenchyma. Conclusion Porcine thyroid anatomy is similar to humans. A key difference is the separation between the thyroid parenchyma and the recurrent laryngeal nerves. The ease of setup, access, and simplicity of instrument manipulation makes open robotic porcine thyroidectomy advantageous for translational research purposes. Characterizing the anatomy and defining the surgical steps may help standardize future research efforts toward open, robotic, and minimal-access thyroid surgery.

Key points Sensory systems are adapted to the statistical structure of natural stimuli, thereby optimizing neural coding. Head motion during natural activities is first sensed and then processed by central vestibulo-motor pathways to influence subsequent behavior, thereby establishing a feedback loop. To investigate the role of this vestibular feedback on the statistical structure of the head movements, we compared head movements in patients with unilateral vestibular loss and healthy controls. We show that the loss of vestibular feedback substantially alters the statistical structure of head motion for activities that require rapid on-line feedback control and predict this change by modeling the effects of increased movement variability. Our findings suggest that, following peripheral vestibular loss, changes in the reliability of the sensory input to central pathways impact the statistical structure of head motion during voluntary behaviors. Abstract It is widely believed that sensory systems are adapted to optimize neural coding of their natural stimuli. Recent evidence suggests that this is the case for the vestibular system, which senses head movement and contributes to essential functions ranging from the most automatic reflexes to voluntary motor control. During everyday behaviors, head motion is sensed by the vestibular system. In turn, this sensory feedback influences subsequent behavior, raising the questions of whether and how real-time feedback provided by the vestibular system alters the statistical structure of head movements. We predicted that a reduction in vestibular feedback would alter head movements statistics, particularly for tasks reliant on rapid vestibular feedback. To test this proposal, we recorded six-dimensional head motion in patients with variable degrees of unilateral vestibular loss during standard balance and gait tasks, as well as dynamic self-paced activities. While distributions of linear accelerations and rotational velocities were comparable for patients and age-matched healthy controls, comparison of power spectra revealed significant differences during more dynamic and challenging activities. Specifically, consistent with our prediction, head movement power spectra were significantly altered in patients during two tasks that required rapid on-line vestibular feedback: active repetitive jumping and walking on foam. Using computational methods, we analyzed concurrently measured torso motion and identified increases in head-torso movement variability. Taken together, our results demonstrate that vestibular loss significantly alters head movement statistics and further suggest that increased variability and impaired feedback to internal models required for accurate motor control contribute to the observed changes. This article is protected by copyright. All rights reserved.

Type I thyroplasty has increasingly been performed on an outpatient basis. Laryngeal reinnervation is recognized for its long-term and functional benefits but is typically performed inpatient under general anesthesia. Herein we report the first published outpatient type I thyroplasty with laryngeal reinnervation performed under monitored anesthesia care (MAC). Three adults underwent type I thyroplasty with ansa cervicalis to recurrent laryngeal nerve (RLN) reinnervation. A 23-year-old female with a history of generalized idiopathic epilepsy s/p vagal nerve stimulator implantation presented with persistent dysphonia. She developed longstanding left vocal fold paralysis. She underwent left type I thyroplasty with silastic implant and ansa cervicalis to RLN neurorrhaphy under MAC-local anesthesia. The patient was discharged home on the day of surgery. Two additional patients underwent the same procedure, including a 58-year-old male with postsurgical dysphonia who was admitted for overnight observation due to a small amount of incisional crepitus and a 23-year-old female with postsurgical vocal cord paralysis who was admitted overnight due to multiple comorbidities. Both were discharged on post-operative day one without issue and demonstrated improvement in voice at follow up. Outpatient type I thyroplasty with laryngeal reinnervation under MAC is feasible with proper patient selection.

We present a case of delayed vocal process granulomas and anterior glottic web after treatment of vocal fold papillomas with a laryngeal microdebrider and CO2 laser ablation. This case highlights a risk of vocal fold granuloma in the setting of recurrent respiratory papillomatosis and microdebrider use, warranting close follow-up and consideration of prophylactic voice therapy, anti-reflux medications, and steroid injection in cases of violation of vocal cord epithelium.

Purpose The purpose of this study was to evaluate the safety, efficacy, and efficiency of a Descemet membrane endothelial keratoplasty (DMEK) graft preparation device, DescePrep, through measurement of graft viability, yield, and preparation time in both healthy and diabetic (high-risk) donor eyes. Methods Twenty nondiabetic and 10 diabetic donor corneas were processed using DescePrep, which standardizes the liquid bubble technique. Corneas were stained with trypan blue and then processed. Cell counts through specular microscopy, optical coherence tomography imaging, and slit-lamp analysis were used for the evaluation of graft separation and viability in 5 nondiabetic corneas. The remaining 25 corneas (15 nondiabetic and 10 diabetic) were evaluated for preparation success rate and processing time. Ten corneas (5 nondiabetic and 5 diabetic) were randomly selected for further evaluation of global cell loss through staining. Results Ninety-seven percent of corneas (29 of 30) were prepared successfully with DescePrep. The average preparation time was 2.83 ± 1.8 minutes. There was no significant difference in the time of preparation between the nondiabetic and diabetic groups (P = 0.077). The overall average cell death after processing was 7.9% ± 3.7% for all corneas. There was no significant difference in cell viability between diabetic and nondiabetic tissues after DescePrep processing (P = 0.769). Conclusions DescePrep is a new DMEK preparation technique that can process both nondiabetic and diabetic donor corneas at high yields in minutes. High-yield preparation of diabetic corneas may offer eye banks access to a larger donor , which is important because the demand for DMEK grafts continues to rise worldwide.

BACKGROUND Postsurgical venous thromboembolism remains a leading cause of hospital morbidity. Data to support venous thromboembolism prophylaxis guidelines in lower extremity flap surgery are lacking. The purpose of this study was to explore the effect of pedicled lower extremity flap harvest on venous thromboembolism development in the setting of abdominal or perineal reconstruction. METHODS One hundred twenty-six patients undergoing unilateral lower extremity flap harvest for abdominal or perineal reconstruction were included. The contralateral leg served as an internal control. Sixty comorbidity-matched patients who underwent abdominal/perineal resection without flap reconstruction provided an external control. Bivariate analyses included chi-square and t tests; logistic regression adjusted for confounding variables on venous thromboembolism development. RESULTS All patients underwent flap reconstruction for an oncologic defect of the abdomen or perineum, with 80 percent undergoing perineal reconstruction. Most patients underwent anterolateral thigh (41 percent) or gracilis flap (40 percent) harvest. Eleven patients developed deep venous thromboses in one or more legs (9 percent): 10 of 11 (90.9 percent) in the donor extremity and five (45.5 percent) contralaterally (p = 0.022). Patients who underwent flap harvest had a 10-fold higher odds of venous thromboembolism formation when compared to comorbidity-matched controls without flap reconstruction (OR, 10.64; 95 percent CI, 1.11 to 102.34; p = 0.041). CONCLUSIONS The rate of venous thromboembolism is higher than previously appreciated for reconstructive procedures of the abdomen and/or perineum that use pedicled lower extremity flaps-particularly in the operative extremity. Additional research can clarify the role for further prophylaxis or screening. CLINICAL QUESTION/LEVEL OF EVIDENCE Therapeutic, III.

Aims: The objective was to evaluate the potential contribution of left atrial (LA) function to reduced exercise capacity in patients with hypertrophic cardiomyopathy (HCM).Methods and results: Using a case-control design we randomly selected 95 patients with confirmed HCM based on guidelines criteria and without permanent atrial arrhythmia who underwent a treadmill exercise test. We measured echo-based left ventricular (LV) and LA morphology and function including mechanics using 2D speckle tracking. Preserved exercise capacity was defined as the 25 th percentile of metabolic equivalents (METs) or > 7 METs. Of 95 HCM patients, 36 had reduced exercise capacity (£7 METs) and 59 had preserved exercise capacity (>7 METs). Reduced exercise capacity patients were more likely to be older, female, had higher BMI, and more advanced heart failure symptoms. They also had a higher E/e’ ratio and lower LA reservoir and conduit strain but similar left ventricular outflow tract (LVOT) pressure gradients. By univariate analysis, LA reservoir and conduit strain, age, gender, BMI, NYHA class, and E/e’ correlated with METs. In multivariate analysis, LA conduit strain independently determined METs after adjusting for age, gender, BMI, NYHA and E/e’ (standardized coefficients 0.17, P=0.04). This relationship was primarily noted in non- and labile-obstructive but not in obstructive HCM. History of atrial fibrillation did not impact the association of LA strain with exercise capacity.Conclusion : Even after adjusting for LVOT gradients and diastolic function, reduced LA conduit strain is an independent determinant of exercise tolerance in HCM.

This cross-sectional study examines the prevlance of xerostomia in adult cochlear implant recipients.

Author(s): Yan, Carol H; Faraji, Farhoud; Prajapati, Divya P; Ostrander, Benjamin T; DeConde, Adam S | Abstract: BackgroundRapid spread of the severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) virus has left many health systems around the world overwhelmed, forcing triaging of scarce medical resources. Identifying indicators of hospital admission for coronavirus disease 2019 (COVID-19) patients early in the disease course could aid the efficient allocation of medical interventions. Self-reported olfactory impairment has recently been recognized as a hallmark of COVID-19 and may be an important predictor of clinical outcome.MethodsA retrospective review of all patients presenting to a San Diego Hospital system with laboratory-confirmed positive COVID-19 infection was conducted with evaluation of olfactory and gustatory function and clinical disease course. Univariable and multivariable logistic regression were performed to identify risk factors for hospital admission and anosmia.ResultsA total of 169 patients tested positive for COVID-19 disease between March 3 and April 8, 2020. Olfactory and gustatory data were obtained for 128 (75.7%) of 169 subjects, of which 26 (20.1%) of 128 required hospitalization. Admission for COVID-19 was associated with intact sense of smell and taste, increased age, diabetes, and subjective and objective parameters associated with respiratory failure. On adjusted analysis, anosmia was strongly and independently associated with outpatient care (adjusted odds ratio [aOR] 0.09; 95% CI, 0.01-0.74), whereas positive findings of pulmonary infiltrates and/or pleural effusion on chest radiograph (aOR 8.01; 95% CI, 1.12-57.49) was strongly and independently associated with admission.ConclusionNormosmia is an independent predictor of admission in COVID-19 cases. Smell loss in COVID-19 may be associated with a milder clinical course.

Background Tissue expansion is used for soft-tissue reconstruction in pediatric patients. The expansion process can be complicated by infection and extrusion, leading to premature expander removal. The aim of this study was to identify risk factors associated with premature expander removal caused by infection or extrusion in pediatric patients. Methods A retrospective study of pediatric patients who underwent tissue expansion performed by the senior author (R.J.R.) over a 12-year period was performed. Predictor variables included age, sex, race, indication, anatomical location, number of expanders, serial expansion, and expander size. Bivariate and multivariate analyses were performed to identify risk factors for premature expander removal. Results A total of 139 patients with 472 expanders were included in this study. Complications occurred with 78 expanders (16.5 percent). Premature expander removal caused by infection or exposure occurred with 51 expanders (10.8 percent). In terms of location, the highest rates of premature removal occurred in the lower extremity (20.0 percent) and scalp (16.3 percent). Multivariate analysis identified younger age (0 to 6 years compared with 13 to 17 years; OR, 3.98; 95 percent CI, 1.13 to 14.08; p = 0.03), greater number of expanders (OR, 1.45; 95 percent CI, 1.03 to 2.03; p = 0.03), and lower extremity location (OR, 4.27; 95 percent CI, 1.45 to 12.53; p = 0.008) were associated with an increased odds of premature expander removal. Conclusions Expander removal occurred in approximately 10 percent of tissue expanders. Odds of premature removal is increased with younger age, greater number of expanders, and lower extremity location. Clinical question/level of evidence Risk, III.

Background As deep inferior epigastric artery perforator (DIEP) flaps have gained popularity in breast reconstruction, the postoperative care of these patients, including the appropriate hospital length-of-stay and the need for intensive care unit (ICU) admission, has become a topic of debate. At our institution, we have adopted a pathway that aims for discharge on postoperative day 3, utilizing continuous tissue oximetry without ICU admission. This study aims to evaluate outcomes with this pathway to assess its safety and feasibility in clinical practice. Methods A retrospective review was performed of patients undergoing DIEP flap breast reconstruction between January 2013 and August 2014. Data of interest included patient demographics and medical history as well as complication rates and date of hospital discharge. Results In total, 153 patients were identified undergoing 239 DIEP flaps. The mean age was 50 years (standard deviation [SD] = 10.2) and body mass index (BMI) 29.4 kg/m2 (SD = 5.2). Over the study period, the flap failure rate was 1.3% and reoperation rate 3.9%. Seventy-one percent of patients were discharged on postoperative day 3. Nine patients required hospitalization beyond 5 days. Theoretical cost savings from avoiding ICU admissions were $1,053 per patient. Conclusion A pathway aiming for hospital discharge on postoperative day 3 without ICU admission following DIEP flap breast reconstruction can be feasibly implemented with an acceptable reoperation and flap failure rate.

Purpose Nonunion is an uncommon complication after mandibular fractures. The purpose of this investigation was to compare outcomes of patients with mandibular fracture nonunion who were treated with a 1- versus 2-stage approach and propose a pragmatic treatment algorithm for surgical management based on preoperative characteristics. Materials and Methods The authors conducted a retrospective study consisting of patients who presented to 2 level 1 trauma centers for the management of mandibular fracture nonunion over a 10-year period. The primary predictor variable was 1- versus 2-stage treatment. Outcomes were examined to propose a treatment algorithm. Results Eighteen patients were included in the study. The sample's mean age was 44.0 ± 19.3 years and most were men (88.9%). Mandibular angle and body accounted for 77.8% of cases. A single-stage approach was used in 13 patients (72.2%). Bone grafts or vascularized bone flaps were required in 13 patients (72.2%). Patients who required 2-stage treatments had intraoral soft tissue defects. Mean length of follow-up was 13.3 ± 20.4 months. All patients achieved bony union, with complications occurring in 5 patients (27.8%). The authors' 10-year experience was used to formulate a treatment algorithm based on bony defect size and soft tissue status, which can be used to inform optimal surgical management. Conclusions Nonunion of mandibular fractures is an infrequent and complex condition requiring careful and deliberate surgical management. A single-stage approach is appropriate in most cases and does not negatively affect outcomes. Bony defect size and soft tissue status are essential parameters for determining the approach and timing of reconstruction.

Background Arteriovenous malformations (AVMs) are high flow vascular anomalies that are difficult to manage given their high recurrence rate. At this time, the optimal treatment of AVMs involves embolization and surgical resection. However, few studies have examined patient outcomes after a delayed surgical resection approach. Methods A retrospective chart review of all patients presenting to a single institution with vascular malformations from 2000 to 2016 was performed. Patients with facial AVMs that underwent operative management were included. Records were reviewed for patient characteristics, lesion natural history, operative timing after embolization ( 72 hours), and outcomes. Results 11 patients fulfilled the inclusion/exclusion criteria. Nine patients were female, with an average age at resection of 29.1 years. Three patients had hemi/mid-facial AVMs, 1 patient had a nasal AVM, 3 patients had labial AVMs, 1 patient had an AVM on the chin, and 1 had a periorbital AVM. Average time between embolization and primary resection was 8.6 days (range 1-24). No complications requiring reoperation occurred in any patient. Average follow-up was 32.6 months, with 2 recurrences at a mean of 47.6 months. Timing of resection, Schobinger stage, and resection completeness did not significantly affect recurrence (P >0.05). Lesion size >6 cm in any dimension was significantly associated with recurrence (P = 0.018). Conclusion Compared to early resection, delayed (>72 h) surgical resection after embolization of facial AVMs is a viable treatment option and results in non-inferior recurrence rates (25 vs 14% respectively over a 40-month period).

Introduction: Hypertrophic cardiomyopathy (HCM) patients are at increased risk for heart failure (HF), stroke, death, and paroxysmal atrial fibrillation (PAF) development. There is no consensus whether atrial fibrillation (AF) is a marker or mediator of adverse outcomes in HCM patients. Hypothesis: We hypothesized that PAF and left atrial (LA) remodeling predict adverse outcomes in HCM. Methods: Echocardiography (2D and speckle tracking) was used to assess LA size, function, and mechanics in a cohort of HCM patients with history of PAF (PAF group, n=45) and age/gender-matched HCM patients without history of AF (No-AF group; n=59). AF was diagnosed by review of EKGs, event recorder/holter monitor data, and ICD interrogation. Patients were followed for a mean of 53 months for development of the composite endpoint of HF, death, and stroke. Results: Clinical/demographic characteristics were similar in the 2 groups; 67% of PAF group had a CHADS 2 VASC score ≤ 1. The PAF group had higher LA volume, lower LA ejection fraction, and higher E/A ratio (reflecting LV diastolic dysfunction) compared to the No-AF group. LA contractile and reservoir strain/strain rate (SR) were significantly lower in the PAF group (Table 1). Male gender, LA reservoir and conduit strain/SR (not PAF presence) were associated with the development of the composite endpoint in univariate analysis. Only LA conduit and reservoir strain/SR independently predicted the composite endpoint in a multivariate model. Kaplan Meier survival analysis showed greater event-free survival among HCM patients with LA conduit strain >10.2% (Figure 1a) and LA reservoir strain >23.8% (p < 0.01) (Figure 1b). Conclusions: PAF is associated with greater degree of LA myopathy in HCM. LA myopathy assessed by conduit and reservoir strain/SR may be useful for risk stratification for HF, stroke, and death in HCM.

Post-operative bedrest is common following perineal reconstruction despite little supporting data. We sought to determine the safety of early ambulation following colorectal oncologic resection and flap-based perineal reconstruction.A retrospective cohort study was conducted with two cohorts: standard bedrest (BC) and early ambulation (EAC). Ambulation capacity was objectively assessed. Regression analysis was performed to determine the effects of ambulation timing on 60-day reoperations or readmissions and other surgical outcomes.There were 57 participants. Those in the EAC were significantly more ambulatory on post-operative days one through three (p 0.0001). There was no significant difference in 60-day reoperations (25% BC versus 9% EAC, p = 0.14) or readmissions (33% BC versus 15% EAC, p = 0.12). Early ambulation significantly reduced minor complication rates (38% BC versus 9% EAC, p = 0.02).Early ambulation following perineal reconstruction is safe and may potentially decrease wound complications.Institution of early ambulation protocols is rapidly becoming the standard of care for many oncological surgery patients. In cases requiring perineal reconstruction with vascularized flaps, however, there is no data to uproot the historical practice of mandatory bedrest. Our study demonstrates that the benefits of early ambulation are attainable in these patients without compromising reconstructive outcomes.

Background Paroxysmal atrial fibrillation (PAF) and left atrial (LA) structural remodeling are common in hypertrophic cardiomyopathy (HCM) patients, who are also at risk for adverse cardiovascular outcomes. Objective We assessed whether PAF and/or LA remodeling was associated with adverse outcomes in HCM. Methods We retrospectively studied 45 HCM patients with PAF (PAF group) and 59 HCM patients without atrial fibrillation (AF; no-AF group). LA/left ventricular (LV) function and mechanics were assessed by echocardiography. Patients were followed for development of the composite endpoint comprising heart failure, stroke, and death. Results Clinical/demographic characteristics, degree of LV hypertrophy, and E/e′ were similar in the two groups The PAF group had significantly higher LA volume, but lower LA ejection fraction (LAEF), LA contractile, and reservoir strain/strain rate than the no-AF group. During follow-up, 27 patients developed the composite endpoint. Incidence of the composite endpoint was similar in the two groups. Absolute values of 23.8% for reservoir strain and 10.2% for conduit strain were the best cutoffs for the composite endpoint, using receiver operating characteristic analysis. Kaplan-Meier survival analysis showed lower event-free survival in patients with reservoir strain ≤23.8% or conduit strain ≤10.2%. Univariate Cox analysis revealed an association between female sex, LAEF, LA reservoir/conduit strain, and LV global longitudinal strain with the composite endpoint. The association between LA reservoir/conduit strain and the composite endpoint persisted after controlling for age, sex, LAEF, and LV global longitudinal strain. Conclusions In this pilot HCM patient study, PAF was associated with a greater degree of LA myopathy, and low LA reservoir and conduit strain were associated with higher risk for adverse cardiovascular outcomes.