Management of Cholesteatoma: Surgical Options for Disease Limited to Middle Ear/Mastoid

Surgery remains the mainstay of cholesteatoma management. Through advancement in technique and technology, the available surgical approaches have expanded to include not only the traditional procedures, but also endoscopic procedures, canal wall reconstruction procedures, mastoid obliteration, and retrograde mastoidotomy. Selection of management technique will depend on disease characteristics, patient factors, and surgeon preference.

Three Parameters Impact the Perception of Smile Asymmetry in Patients with Facial Paralysis

Background: The ability to smile is impaired in patients with facial palsy, and objective parameters assessing smile symmetry to guide treatment are not well elucidated. Objective: This study seeks to identify objective facial measurements that relate smile recognition, perception of smile asymmetry, and perceived emotions from photographs of individuals with asymmetrical smiles compared with control photographs of individuals without smile asymmetry as measured by a photograph analysis application. Methods: Fifty-six photographs of smiles were categorized using objective perioral morphometric measurements (Emotrics). A photographic survey of these smiles was disseminated with queries regarding smile symmetry, smile recognition, and emotion perception. Generalized linear mixed modeling (GLMM) was performed to assess the effect of facial measurements on survey responses. Results: From 756 survey responses, smile symmetry predicted for smile recognition (F = 1084, p < 0.001) and emotion perception (F = 422, p < 0.001). Correlation analysis and GLMM identified three parameters (lower lip height, commissure position, and commissure height) that predicted smile recognition (F = 1040, p < 0.001), emotion perception (F = 976, p < 0.001), and symmetry (F = 1248, p < 0.001). Lower lip height (β = -57.84, p < 0.001) and commissure position (β = -29.41, p < 0.001) were the most significant drivers. Conclusions: Correcting lower lip height and commissure position represents efficacious clinical benchmarks for improving smile recognition by reducing smile asymmetry and conveying negative emotions.

Peripheral Nerve Injury After Deoxycholic Acid (ATX-101) Injection in an Experimental Rat Model

BACKGROUND

Deoxycholic acid (ATX-101) is a drug administered by subcutaneous injection for local fat reduction. However, ATX-101 treatment has been reported to cause marginal mandibular nerve injury with noticeable functional deficits when targeting submental fat. As a cytolytic agent with some selectivity for adipocytes, ATX-101 may damage the lipid-rich myelin surrounding peripheral nerves.

OBJECTIVES

This study seeks to characterize the nerve injection injury from ATX-101 in an experimental rat model.

METHODS

Using a rat sciatic nerve injection model, intrafascicular and extrafascicular injections of deoxycholic acid (ATX-101) were compared to lidocaine (positive control) and saline (negative control). Nerves were harvested at a 2-week endpoint for histomorphometric analysis.

RESULTS

Cross-sectional area of nerve injury was significantly increased by ATX-101 injection at 75±15% with intrafascicular ATX-101 (p<0.001), 41±21% with extrafascicular ATX-101 (p<0.01), and 38±20% with positive control lidocaine (p<0.01) compared to 7±13% with negative control saline. Demyelinating injury was a significant mechanism of injury in the affected nerve fibers compared to uninjured nerve fibers (p<0.04), but there was no difference in axon-to-myelin area ratio between the lidocaine and ATX-101 cohorts. After two weeks, Wallerian degeneration was evident with only small regenerating nerve fibers present in the ATX-101-injured groups compared to saline (2.54±0.26um vs 5.03±0.44um, p<0.001) in average width.

CONCLUSIONS

Deoxycholic acid (ATX-101) is capable of extensive nerve injury in rats. The mechanism of action for ATX-101 does not preferentially target myelin more than other common neurotoxic agents. Appropriate knowledge of surgical anatomy and injection technique is necessary for any practitioners providing ATX-101 injections.

The Impact of Area Deprivation Index, Geography, and Mechanism on Incidence of Ballistic Injury to the Upper Extremity

INTRODUCTION

This study investigates the intersection of ballistic injuries, geography, and Area Deprivation Index (ADI). We hypothesized that both ADI and geography are correlated with incidence of upper extremity ballistic injuries. Further, we characterize and compare 2 distinct upper extremity gunshot injury populations presenting to our institution: those sustaining violent ballistic injuries and those who suffer an accidental, self-inflicted injury. Our purpose is to evaluate the impact of geography and ADI on the pattern of upper extremity gunshot injuries in Illinois and Missouri.

MATERIALS AND METHODS

This was a retrospective review of adult patients sustaining ballistic injury to the upper extremity at a single urban level I trauma center over 10 years (n = 797). Seven hundred thirty patients had home addresses in Illinois or Missouri; these addresses were geocoded and included for analysis. Mechanism of injury was self-reported. ADI was measured from the 2019 Neighborhood Atlas, in which deprivation increases from 1 to 100. Comparisons between groups were conducted with unpaired t tests, Fisher exact test, or χ2 testing, where appropriate.

RESULTS

Addresses constituted 259 unique census tracts, and the average number of upper extremity gunshot wound incidents per tract was 3, with a maximum of 22; 15.4% of census block tracts made up almost half (48.4%) of the total ballistic injuries in the study period; 97.7% of violent injuries occurred in Urban areas, as compared with only 60% of accidental injuries (P < 0.05). ADI and incidence of upper extremity ballistic injury were positively correlated. ADI varied significantly between patients sustaining violent (median, 94; mean, 86.1) versus accidental self-inflicted (median, 79; mean, 70.9) injuries (P < 0.05). Fifty percent of violent injuries in our data set occurred in block groups from the 2 most deprived quintiles.

CONCLUSIONS

Upper extremity gunshot wounds in general are concentrated in census blocks with high ADI. Violent injuries in particular are more likely to occur in urban areas with high ADI, whereas patients with accidental, self-inflicted injuries are more geographically and socioeconomically diverse. These differing populations require unique approaches to reduce incidence and morbidity.

Escalating Surgical Treatment for Left Ventricular Assist Device Infection and Expected Mortality: Clinical Risk Prediction Score

BACKGROUND

Left ventricular assist devices (LVAD) improve survival for patients with cardiac failure, but LVAD-specific infection (VSI) remains a challenge with poorly understood predictive risk factors. The indications and use of escalating medical treatment to surgical debridement and potential flap reconstruction are not well characterized.

STUDY DESIGN

A retrospective review of consecutive patients undergoing primary LVAD implantation at a tertiary academic center was performed. The primary outcome measures were 90-day and overall mortality after VSI. Cox proportional hazards regression was used to generate a risk prediction score for mortality.

RESULTS

Of the 760 patients undergoing primary LVAD implantation, 255 (34%) developed VSI; of these patients, 91 (36%) were managed medically, 134 (52%) with surgical debridement, and 30 (12%) with surgical debridement and flap reconstruction. One-year survival after infection was 85% with median survival of 2.40 years. Factors independently associated with increased mortality were diabetes (hazard ratio [HR] 1.44, p = 0.04), MRSA infection (HR 1.64, p = 0.03), deep space (pump pocket or outflow cannula) involvement (HR 2.26, p < 0.001), and extracorporeal membrane oxygenation after LVAD (HR 2.52, p < 0.01). Factors independently associated with decreased mortality were flap reconstruction (HR 0.49, p = 0.02) and methicillin-sensitive Staphylococcus aureus infection (HR 0.63, p = 0.03). A clinical risk prediction score was developed using these factors and showed significant differences in median survival, which was 5.67 years for low-risk (score 0 to 1), 3.62 years for intermediate-risk (score 2), and 1.48 years for high-risk (score ≥3; p < 0.001) patients.

CONCLUSIONS

We developed a clinical risk prediction score to stratify patients with VSI. In selected cases, escalating surgical treatment was associated with increased survival. Future work is needed to determine whether early surgical debridement and flap reconstruction can alter outcomes in select cases of VSI.

Antibiotic Prophylaxis and Infectious Complications in Isolated Gunshot Wounds to the Upper Extremity

BACKGROUND

Prophylactic antibiotics are variably prescribed after isolated upper extremity gunshot wounds (UE GSWs). The risk of infection and factors influencing prescribing practice remain poorly understood, and clinical practice guidelines are lacking.

METHODS

Adults with isolated UE GSWs over a 10-year period were included. Medical records were reviewed for demographic and injury variables, comorbidities, surgical treatments, antibiotic administration, infectious complications, and follow-up duration. Infection rate was calculated. Bivariate and multivariable linear regression analyses were used to identify patient-related and injury-related factors predictive of prophylactic antibiotic prescription.

RESULTS

A total of 281 patients were eligible for inclusion. Prophylactic antibiotics were prescribed at discharge for 111 patients (40%). Multivariable analysis revealed that patients with more distal injuries and ballistic fractures were significantly more likely to receive prophylactic antibiotics. Of patients with at least 30-day postinjury follow-up, 6% developed infections.

CONCLUSION

Prophylactic antibiotic administration after UE GSWs was inconsistent but more common in patients with ballistic fractures and injuries in the hand. The overall incidence of infection was found to lie between 3% and 6%. The rate of infection in the antibiotic prophylaxis (2%-6%) group was similar to that in the no-antibiotic (5%-7%) group, suggesting that antibiotic prophylaxis may not have a large impact on infectious risk. However, because this study is nonrandomized, and because this study is underpowered for multivariable modeling of infectious risk, it remains possible that subgroups of this population may still benefit from antibiotic prophylaxis.

Degrees of Inflammation in the Treatment of Subglottic Stenosis in a Rabbit Model: Histopathological Assessment of a Novel Bioabsorbable Ultra-high Ductility Magnesium Alloy Stent

OBJECTIVE

Utilizing a novel histopathological scoring system and subglottic stenosis (SGS) rabbit model, we aimed to compare degrees of inflammation and severity of narrowing in the subglottis between two minimally invasive therapeutic modalities: endoscopic balloon dilation (EBD) alone versus EBD with placement of a bioabsorbable ultra-high ductility magnesium (UHD-Mg) alloy stent.

METHODS

SGS was induced endoscopically via microsuspension laryngoscopy in 23 New Zealand white rabbits. The control group (n = 11) underwent EBD alone, the study arm (n = 12) underwent EBD with implantation of bioabsorbable UHD-Mg alloy stents. Rabbits were euthanized at 2-, 3-, and 6-weeks after SGS induction, coinciding with wound healing stages. Using Optical Coherence Tomography (OCT), cross-sectional areas of airways were compared to calculate the mean percentage of intraluminal area at sequential time points. A novel histopathological scoring system was used to analyze frozen sections of laryngotracheal complexes. The degree of inflammation was quantified by scoring changes in inflammatory cell infiltration, epithelial ulceration/metaplasia, subepithelial edema/fibrosis, and capillary number/dilation. Univariate analysis was utilized to analyze these markers.

RESULTS

We found rabbits implanted with the bioabsorbable UHD-Mg alloy stent had statistically significantly higher scores in categories of hyperplastic change (stents vs controls: 1.48 vs 0.46 p < 0.001), squamous metaplasia (22 vs 5 p < 0.001), and neutrophils/fibrin in lumen (31 vs 8, p < 0.001). Rabbits who received EBD alone had higher scores of subepithelial edema and fibrosis (2.70 vs 3.49, p < 0.0256). The stented rabbits demonstrated significantly increased mean percent stenosis by intraluminal mean area compared to controls at 2 weeks (88.56 vs 58.98, p = 0.032), however at all other time points there was no significant difference between intraluminal subglottic stenosis by mean percent stenosis area.

DISCUSSION

Rabbits with SGS treated with UHD-Mg alloy stents demonstrated histopathologic findings suggestive of lower levels of tracheal fibrosis. This could indicate a reduced tendency towards the development of stenosis when compared to EBD alone. There was not a difference in luminal size between stent and non-stented rabbits at the six-week end point. Histologically, however, overall the use of bioabsorbable UHD-Mg alloy stenting elicited a greater tissue response at the level of the superficial mucosa rather than fibrosis of the lamina propria seen in the stented rabbits. This suggests more favorable healing and less of a tendency towards fibrosis and stenosis even though there may not be a benefit from a luminal size standpoint during this early healing period. Compared to known complications of currently available non-bioabsorbable metal or silicone-based stents, this proof-of-concept investigation highlights the potential use of a novel biodegradable UHD-Mg stent as a therapeutic modality for pediatric SGS.

Congenital Cytomegalovirus Testing Outcomes From the ValEAR Trial

OBJECTIVE

To determine the positivity rate of congenital cytomegalovirus (cCMV) testing among universal, hearing-targeted CMV testing (HT-cCMV) and delayed targeted dried blood spot (DBS) testing newborn screening programs, and to examine the characteristics of successful HT-cCMV testing programs.

STUDY DESIGN

Prospective survey of birth hospitals performing early CMV testing.

SETTING

Multiple institutions.

METHODS

Birth hospitals participating in the National Institutes of Health ValEAR clinical trial were surveyed to determine the rates of cCMV positivity associated with 3 different testing approaches: universal testing, HT-cCMV, and DBS testing. A mixed methods model was created to determine associations between successful HT-cCMV screening and specific screening protocols.

RESULTS

Eighty-two birth hospitals were surveyed from February 2019 to December 2021. Seven thousand six hundred seventy infants underwent universal screening, 9017 infants HT-cCMV and 535 infants delayed DBS testing. The rates of cCMV positivity were 0.5%, 1.5%, and 7.3%, respectively. The positivity rate for universal CMV screening was less during the COVID-19 pandemic than that reported prior to the pandemic. There were no statistically significant drops in positivity for any approach during the pandemic. For HT-cCMV testing, unique order sets and rigorous posttesting protocols were associated with successful screening programs.

CONCLUSION

Rates of cCMV positivity differed among the 3 approaches. The rates are comparable to cohort studies reported in the literature. Universal CMV prevalence decreased during the pandemic but not significantly. Institutions with specific order set for CMV testing where the primary care physician orders the test and the nurse facilitates the testing process exhibited higher rates of HT-cCMV testing.

Free functional muscle transfer for lower extremity reconstruction

BACKGROUND

Free functional muscle transfer is a reconstructive strategy for the reconstruction of lost muscle units in the lower extremity after oncologic resection, trauma, compartment syndrome, or severe nerve injuries. Under appropriate circumstances, free functional muscle transfer may be the only suitable reconstructive option. This article reviews the underlying principles of free functional muscle transfer, its application to lower extremity reconstruction, appropriate patient selection, and surgical techniques.

METHODS

The underlying principles of free functional muscle transfer, its application to lower extremity reconstruction, appropriate patient selection, and surgical techniques are presented. Commonly used donor muscles appropriate for each type of functional defect are discussed. A review of recent publications on free functional muscle transfer in the lower extremity was also performed.

RESULTS

Good functional recovery with a Medical Research Council grade of up to 4/5 and full range of motion can be attained with free functional muscle transfer. Clinical outcomes and specific parameters for published case series in lower extremity free functional muscle transfer are presented and an illustrative case.

CONCLUSION

Free functional muscle transfer is a suitable treatment for the appropriate patient to restore essential functions and potentially regain ambulation. However, additional published clinical outcomes are needed and represent a major area for further investigation.

Utility of Intraoperative Radiographs in Pediatric Cochlear Implant Surgery

OBJECTIVE

To evaluate the role of intraoperative radiographs to confirm electrode position following pediatric cochlear implantation (CI).

STUDY DESIGN

Retrospective chart review.

SETTING

Single tertiary care pediatric center.

METHODS

A retrospective chart review was conducted, including all pediatric patients undergoing CI at UPMC Children's Hospital of Pittsburgh over a 13-year period.

RESULTS

We identified 326 patients undergoing 492 procedures. Across the cohort, there were 7 cases that required intraoperative electrode reinsertion due to malposition or presumed malposition. For 6 of the 7 cases, intraoperative X-ray identified electrode malposition. Neural response telemetry (NRT) testing was also abnormal for 4 of these cases prior to reinsertion. Implantation of Cochlear's Slim Modiolar electrode was associated with an abnormal perioperative X-ray (odds ratio [OR]: 9.2, p = 0.03) and increased change in management (OR: 9.2, p = 0.03) compared to Cochlear's Contour Advance (CA). Incidence of abnormal X-rays was 1.24% overall, 4% in the Slim Modiolar group, and 0.3% in the CA group. The Slim Modiolar electrode accounted for 4 of 7 cases requiring reinsertion, and in all 4 of these cases, electrode fold-over was identified on the X-ray. NRT was normal in 1 of these 4 cases.

CONCLUSION

The use of Cochlear's Slim Modiolar electrode was associated with a significantly increased risk of abnormal intraoperative X-ray compared to the CA electrode. Given the risk of fold-over with routine insertion and normal electrical testing using the Slim Modiolar electrode, we recommend routine use of intraoperative skull X-ray to confirm electrode position.

A Surgical Framework for the Management of Incomplete Axillary Nerve Injuries

BACKGROUND

 Axillary nerve injury is the most common nerve injury affecting shoulder function. Nerve repair, grafting, and/or end-to-end nerve transfers are used to reconstruct complete neurotmetic axillary nerve injuries. While many incomplete axillary nerve injuries self-resolve, axonotmetic injuries are unpredictable, and incomplete recovery occurs. Similarly, recovery may be further inhibited by superimposed compression neuropathy at the quadrangular space. The current framework for managing incomplete axillary injuries typically does not include surgery.

METHODS

 This study is a retrospective analysis of 23 consecutive patients with incomplete axillary nerve palsy who underwent quadrangular space decompression with additional selective medial triceps to axillary end-to-side nerve transfers in 7 patients between 2015 and 2019. Primary outcome variables included the proportion of patients with shoulder abduction M3 or greater as measured on the Medical Research Council (MRC) scale, and shoulder pain measured on a Visual Analogue Scale (VAS). Secondary outcome variables included pre- and postoperative Disabilities of the Arm, Shoulder, and Hand Questionnaire (DASH) scores.

RESULTS

 A total of 23 patients met the inclusion criteria and underwent nerve surgery a mean 10.7 months after injury. Nineteen (83%) patients achieved MRC grade 3 shoulder abduction or greater after intervention, compared with only 4 (17%) patients preoperatively (p = 0.001). There was a significant decrease in VAS shoulder pain scores of 4.2 ± 2.5 preoperatively to 1.9 ± 2.4 postoperatively (p < 0.001). The DASH scores also decreased significantly from 48.8 ± 19.0 preoperatively to 30.7 ± 20.4 postoperatively (p < 0.001). Total follow-up was 17.3 ± 4.3 months.

CONCLUSION

 A surgical framework is presented for the appropriate diagnosis and surgical management of incomplete axillary nerve injury. Quadrangular space decompression with or without selective medial triceps to axillary end-to-side nerve transfers is associated with improvement in shoulder abduction strength, pain, and DASH scores in patients with incomplete axillary nerve palsy.

Mechanism matters: A 10-year experience of ballistic injuries of the upper extremity

INTRODUCTION

Upper Extremity gunshot wounds represent a significant strain on community and hospital resources, and reports of their epidemiology are varied. We hypothesized that demographic and socioeconomic variables would be associated with variable injury patterns and management, and that two distinct populations would be affected by upper extremity ballistic injury based on violent versus accidental, self-inflicted mechanism.

MATERIALS & METHODS

Retrospective review of all adult patients sustaining ballistic injury to the upper extremity at a single urban Level I trauma center over 10 years (n = 797). Demographic, injury pattern, treatment, and outcomes data were collected. Comparisons between groups were conducted with unpaired t-tests and chi-square testing where appropriate.

RESULTS

Most patients were male (89.1%) and mean age was 30.1 years (18-83). Violence accounted for 89.1% of injuries. Black individuals were disproportionately affected at 87% of patients. Shoulder injuries were most common (34%), and wrist least common (7%). Demographics and injury pattern varied significantly between patients sustaining violent injury and those with self-inflicted mechanisms. Patients sustaining violent injury were most often young, Black men more likely to be injured proximally, whereas patients with self-inflicted injuries were more likely to be older, Caucasian men with more comorbidities injured distally. Cumulatively, 35.3% of patients required operative intervention. Distal injuries were more likely operative. The most commonly injured structure across all levels was bone (53%), and 54.3% of fractures required operation. Median follow-up was 24.5 months. Complication rate was 13.6%.

CONCLUSIONS

Gunshot wounds of the upper extremity create complex patterns of injury which vary based on level of injury and mechanism. Violent and self-inflicted injuries occur in dissimilar populations and result in distinctive injury patterns.

A multi-institutional survey on calvarial vault remodeling techniques for sagittal synostosis and outcomes analysis for patients treated at 12 months and older

OBJECTIVE

Surgical treatment of sagittal craniosynostosis is challenging in older patients. This study aimed to assess the effect of increasing age on open surgical technique selection and patient outcomes using the multi-institutional Synostosis Research Group (SynRG) collaboration.

METHODS

Surgeons in SynRG were surveyed for key influences on their preferred open calvarial vault remodeling techniques at various patient ages: < 6, 6-12, and > 12 months. The SynRG database was then queried for open repairs of nonsyndromic sagittal craniosynostosis performed for patients older than 12 months of age. Perioperative measures, complications, and preoperative and postoperative cephalic indices were reviewed.

RESULTS

All surgeons preferred to treat patients at an earlier age, and most (89%) believed that less-optimal outcomes were achieved at ages older than 12 months. The modified pi procedure was the dominant technique in those younger than 12 months, while more involved open surgical techniques were performed for older patients, with a wide variety of open calvarial vault remodeling techniques used. Forty-four patients met inclusion criteria, with a mean (± SD) age at surgery of 29 ± 16 months. Eleven patients underwent parietal reshaping, 10 parietal-occipital switch, 9 clamshell craniotomy, 7 geometric parietal expansion, 6 modified pi procedure, and 1 parietal distraction. There were no readmissions, complications, or mortality within 30 days postoperatively. Patients' cephalic indices improved a mean of 6.4% ± 4.0%, with a mean postoperative cephalic index of 74.2% ± 4.9%. Differences in postoperative cephalic index (p < 0.04) and hospital length of stay (p = 0.01) were significant between technique cohorts. Post hoc Tukey-Kramer analysis identified the parietal reshaping technique as being significantly associated with a reduced hospital length of stay.

CONCLUSIONS

Patient age is an important driver in technique selection, with surgeons selecting a more involved calvarial vault remodeling technique in older children. A variety of surgical techniques were analyzed, with the parietal reshaping technique being significantly associated with reduced length of stay; however, multiple perioperative factors may be contributory and require further analysis. When performed at high-volume centers by experienced pediatric neurosurgeons and craniofacial surgeons, open calvarial vault techniques can be a safe method for treating sagittal craniosynostosis in older children.

Abstract 78: Detection of gene fusions and exon skipping events in lung FFPE samples with Oncomine Precision Assay on Ion Torrent Genexus࣪ System

Introduction: Gene fusions and exon skipping events play an important oncogenic role in non-small cell lung cancer (NSCLC). Here we employed the Oncomine Precision Assay (OPA) for sequencing of 998 clinical research FFPE (Formalin-Fixed Paraffin-Embedded) lung samples using the Genexus࣪ integrated sequencing platform. The RNA assay strategy is aimed at providing a wide scope for studying known oncogenic fusions and exon skip variants, as well as a method for detection of novel fusion combinations and detection of fusions in a partner agnostic manner. We summarize the findings that include detected samples with oncogenic fusions in tyrosine kinase genes ALK, RET, ROS1 as well as MET exon14 skipping, and demonstrate the novel fusion detection capabilities of the panel.

Methods: The Oncomine Precision Assay panel developed using the Ion AmpliSeq HD technology for use on both tissue and liquid biopsy samples to detect fusions with high sensitivity in low input RNA. The panel features 981 known fusion isoforms in 16 oncogenic drivers as well as assays for exon skipping and deletion in MET and EGFR. The amplicons are strategically designed around known fusion breakpoints and generate reads only if the variant is present. Results are assessed bioinformatically with a framework that includes detailed genomic annotations of the fusion breakpoint, and generates interpretable fusion calls and report in the Genxus࣪ software. In addition, the panel contains an algorithm for novel fusion detection, and 78 exon-junction amplicons for partner agnostic fusion detection in ALK, RET, NTRK1,2,3 and FGFR1,2,3 with an exon tiling expression imbalance assay. We used the Genexus࣪ instrument to sequence 998 unique lung FFPE samples and analyzed the results with the Genexus࣪ fusion analysis workflow.

Results: A total of 998 unique lung FFPEs were sequenced, of which 906 (91%) resulted with &gt;5000 aligned reads and at least 5 of the 7 RNA expression controls at the assay threshold. A total of 25 samples with ALK fusions were detected by either the targeted fusions or the expression imbalance assays. In addition, we detected 10 samples with RET fusions, 4 with FGFR3 fusions, 3 with ROS1 fusions, and additional single observations of NRG1, RSPO3 and FGFR1 fusions. Exon 14 skipping in MET was detected in 14 samples, of which we were able to detect a likely splice site variant SNV or indel at, or near the boundaries of exon 14, with the DNA assays of the panel. These variants were observed in a mutually exclusive set of 59 total samples (6.5% of the samples).

Conclusions: We used the OPA panel for fusions and intragenic rearrangements that retains the simple workflow and fast turn-around time of previous Oncomine fusion, and demonstrated known and novel fusion detection as well exon skip variant detection capabilities in a research cohort of lung FFPE samples. For research use only. Not for use in diagnostic procedures.

Citation Format: Amir Marcovitz, Jeoffrey Schageman, Jian Gu, Stephen Wunsch, David Chi, Paul D. williams, Scott P. Myrand, Fiona C. Hyland, Seth Sadis, Kelli S. Bramlett. Detection of gene fusions and exon skipping events in lung FFPE samples with Oncomine Precision Assay on Ion Torrent Genexus࣪ System [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 78.

Complete Foot Drop With Normal Electrodiagnostic Studies: Sunderland "Zero" Ischemic Conduction Block of the Common Peroneal Nerve

ABSTRACT

Common peroneal neuropathy is a peripheral neuropathy of multifactorial etiology often left undiagnosed until foot drop manifests and electrodiagnostic abnormalities are detected. However, reliance on such striking symptoms and electrodiagnostic findings for diagnosis stands in contrast to other commonly treated neuropathies, such as carpal tunnel and cubital tunnel syndrome. Poor recognition of common peroneal neuropathy without foot drop or the presence of foot drop with normal electrodiagnostic studies thus often results in delayed or no surgical treatment. Our cases document 2 patients presenting with complete foot drop who had immediate resolution after decompression. The first patient presented with normal electrodiagnostic studies representing an isolated Sunderland Zero nerve ischemia. The second patient presented with severe electrodiagnostic studies but also had an immediate improvement in their foot drop representing a Sunderland VI mixed nerve injury with a significant contribution from an ongoing Sunderland Zero ischemic conduction block. In support of recent case series, these patients demonstrate that common peroneal neuropathy can present across a broad diagnostic spectrum of sensory and motor symptoms, including with normal electrodiagnostic studies. Four clinical subtypes of common peroneal neuropathy are presented, and surgical decompression may thus be indicated for these patients that lack the more conventional symptoms of common peroneal neuropathy.

Antioxidative and Angiogenic Hyaluronic Acid-Based Hydrogel for the Treatment of Peripheral Artery Disease

Peripheral arterial disease (PAD) is a progressive atherosclerotic disorder characterized by blockages of the arteries supplying the lower extremities. Ischemia initiates oxidative damage and mitochondrial dysfunction in the legs of PAD patients, causing injury to the tissues of the leg, significant decline in walking performance, leg pain while walking, and in the most severe cases, nonhealing ulcers and gangrene. Current clinical trials based on cells/stem cells, the trophic factor, or gene therapy systems have shown some promising results for the treatment of PAD. Biomaterial matrices have been explored in animal models of PAD to enhance these therapies. However, current biomaterial approaches have not fully met the essential requirements for minimally invasive intramuscular delivery to the leg. Ideally, a biomaterial should present properties to ameliorate oxidative stress/damage and failure of angiogenesis. Recently, we have created a thermosensitive hyaluronic acid (HA) hydrogel with antioxidant capacity and skeletal muscle-matching stiffness. Here, we further optimized HA hydrogels with the cell adhesion peptide RGD to facilitate the development of vascular-like structures in vitro. The optimized HA hydrogel reduced intracellular reactive oxygen species levels and preserved vascular-like structures against H₂O₂-induced damage in vitro. HA hydrogels also provided prolonged release of the vascular endothelial growth factor (VEGF). After injection into rat ischemic hindlimb muscles, this VEGF-releasing hydrogel reduced lipid oxidation, regulated oxidative-related genes, enhanced local blood flow in the muscle, and improved running capacity of the treated rats. Our HA hydrogel system holds great potential for the treatment of the ischemic legs of patients with PAD.

Impact of Patient Socioeconomic Disparities on Time to Tympanostomy Tube Placement

OBJECTIVES

Extensive literature exists documenting disparities in access to healthcare for patients with lower socioeconomic status (SES). The objective of this study was to examine access disparities and differences in surgical wait times in children with the most common pediatric otolaryngologic surgery, tympanostomy tubes (TT).

METHODS

A retrospective cohort study was performed at a tertiary children's hospital. Children ages <18 years who received a first set of tympanostomy tubes during 2015 were studied. Patient demographics and markers of SES including zip code, health insurance type, and appointment no-shows were recorded. Clinical measures included risk factors, symptoms, and age at presentation and first TT.

RESULTS

A total of 969 patients were included. Average age at surgery was 2.11 years. Almost 90% were white and 67.5% had private insurance. Patients with public insurance, ≥1 no-show appointment, and who lived in zip codes with the median income below the United States median had a longer period from otologic consult and preoperative clinic to TT, but no differences were seen in race. Those with public insurance had their surgery at an older age than those with private insurance (P < .001) and were more likely to have chronic otitis media with effusion as their indication for surgery (OR: 1.8, 95% CI: 1.2-2.5, P = .003).

CONCLUSIONS

Lower SES is associated with chronic otitis media with effusion and a longer wait time from otologic consult and preoperative clinic to TT placement. By being transparent in socioeconomic disparities, we can begin to expose systemic problems and move forward with interventions.

LEVEL OF EVIDENCE

4.

Hospital volume is associated with cost and outcomes variation in 2,942 pelvic reconstructions

BACKGROUND

Complex pelvic reconstruction is challenging for plastic and reconstructive surgeons following surgical resection of the lower gastrointestinal or genitourinary tract. Complication rates and hospital costs are variable and may be linked to the hospital case volume of pelvic reconstructions performed. A comprehensive examination of these factors has yet to be performed.

METHODS

Data were retrieved for patients undergoing pedicled flap reconstruction after pelvic resections in the American National Inpatient Sample database between 2010 and 2014. Patients were then separated into three groups based on hospital case volume for pelvic reconstruction. Multivariate logistic regression and gamma regression with log-link function were used to analyze associations between hospital case volume, surgical outcomes, and cost.

RESULTS

In total, 2,942 patients underwent pelvic flap reconstruction with surgical complications occurring in 1,466 patients (49.8%). Total median cost was $38,469.40. Pelvic reconstructions performed at high-volume hospitals were significantly associated with fewer surgical complications (low: 51.4%, medium: 52.8%, high: 34.8%; p < 0.001) and increased costs (low: $35,645.14, medium: $38,714.92, high: $44,967.29; p < 0.001). After regression adjustment, high hospital volume was the strongest independently associated factor for decreased surgical complications (Exp[β], 0.454; 95% Confidence Interval, 0.346-0.596; p < 0.001) and increased hospital cost (Exp[β], 1.351; 95% Confidence Interval, 1.285-1.421; p < 0.001).

CONCLUSIONS

Patients undergoing pelvic flap reconstruction after oncologic resections experience high complication rates. High case volume hospitals were independently associated with significantly fewer surgical complications but increased hospital costs. Reconstructive surgeons may approach these challenging patients with greater awareness of these associations to improve outcomes and address cost drivers.

En Bloc Capsulectomy for Breast Implant Illness: A Social Media Phenomenon?

BACKGROUND

En bloc capsulectomy has recently increased in prominence as a potential surgical therapy for patients with breast implant illness (BII). However, this procedure has chiefly been recommended for treating breast implant-associated anaplastic large cell lymphoma (BIA-ALCL).

OBJECTIVES

This study aimed to review the current literature and evaluate the public understanding of treatment options for BII via social media to characterize any potential communication disconnect between clinicians and patients.

METHODS

An electronic literature review was performed to identify all available publications mentioning evidence-based support for en bloc capsulectomy as treatment for BII and BIA-ALCL. Twitter social media posts referencing BII or BIA-ALCL were analyzed from 2010 to 2019. Author identity and any mention of surgical treatment were assessed.

RESULTS

A total of 115 publications on the subject of BII and 315 articles on BIA-ALCL were identified. En bloc resection was recommended only for patients with a diagnosis of BIA-ALCL. A total of 6419 tweets referencing BII and 6431 tweets referencing BIA-ALCL were identified. Tweets referencing BIA-ALCL were significantly more likely to be authored by physicians (25.9% vs 5.3%, P < 0.001), and tweets referencing BII were significantly more likely to mention any surgical treatment (7.8% vs 1.9%, P < 0.001) and en bloc capsulectomy (1.4% vs 0.3%, P < 0.001).

CONCLUSIONS

This study demonstrates that a communication disconnect exists between the scientific literature and social media regarding treatment options for BII and BIA-ALCL. Physicians should be aware of these potential misconceptions to empathetically address patient concerns in a patient-centered manner.

Advanced Practice Provider Clinics: Expediting Care For Children Undergoing Tympanostomy Tube Placement

OBJECTIVE/HYPOTHESIS

Advanced practice provider (APP) employment is becoming common in pediatric otolaryngology practices, though few studies have evaluated the consequences that APP-led clinics have on access to care. The objectives of this study were: 1) to investigate whether access to bilateral myringotomy with tympanostomy tube placement (BMT) for recurrent acute otitis media (RAOM) differed between patients seen in otolaryngologist and APP-led clinics 2) to compare clinical characteristics of patients seen by provider type.

METHODS

Retrospective cohort study at an academic, tertiary care pediatric otolaryngology practice. All children were <18 years old and underwent evaluation for RAOM followed by BMT. We compared time in days from scheduling pre-operative appointment to appointment date and time from appointment to BMT between patients seen by APPs and otolaryngologists using Mann-Whitney U tests and multivariate linear regression models. We compared clinical characteristics by provider type using Mann-Whitney U tests and Fisher exact tests.

RESULTS

A total of 957 children were included. Children seen by APPs had significantly shorter wait times for appointments (median 19 vs. 39 days, P < .001) and shorter times from preoperative appointment to BMT (median 25 vs. 37 days, P < .001). Patients seen by otolaryngologists had increased prevalence of craniofacial abnormalities, Down Syndrome, hearing loss, history of otologic surgery, and higher ASA physical status classification.

CONCLUSIONS

Children seen by APPs received care more quickly than those seen by otolaryngologists. Patients seen by otolaryngologists tended to be more medically complex. Implementation of independent APP clinics may expedite and improve access to BMT for children with RAOM.

LEVEL OF EVIDENCE

3 Laryngoscope, 131:2133-2140, 2021.

Natural Killer Cell Phenotype and Functionality Affected by Exposure to Extracellular Survivin and Lymphoma-Derived Exosomes

The inherent abilities of natural killer (NK) cells to recognize and kill target cells place them among the first cells with the ability to recognize and destroy infected or transformed cells. Cancer cells, however, have mechanisms by which they can inhibit the surveillance and cytotoxic abilities of NK cells with one believed mechanism for this: their ability to release exosomes. Exosomes are vesicles that are found in abundance in the tumor microenvironment that can modulate intercellular communication and thus enhance tumor malignancy. Recently, our lab has found cancer cell exosomes to contain the inhibitor of apoptosis (IAP) protein survivin to be associated with decreased immune response in lymphocytes and cellular death. The purpose of this study was to explore the effect of survivin and lymphoma-derived survivin-containing exosomes on the immune functions of NK cells. NK cells were obtained from the peripheral blood of healthy donors and treated with pure survivin protein or exosomes from two lymphoma cell lines, DLCL2 and FSCCL. RNA was isolated from NK cell samples for measurement by PCR, and intracellular flow cytometry was used to determine protein expression. Degranulation capacity, cytotoxicity, and natural killer group 2D receptor (NKG2D) levels were also assessed. Lymphoma exosomes were examined for size and protein content. This study established that these lymphoma exosomes contained survivin and FasL but were negative for MHC class I-related chains (MIC)/B (MICA/B) and TGF-β. Treatment with exosomes did not significantly alter NK cell functionality, but extracellular survivin was seen to decrease natural killer group 2D receptor (NKG2D) levels and the intracellular protein levels of perforin, granzyme B, TNF-α, and IFN-γ.