Prolonged operative time predicts postoperative deep venous thrombosis in head and neck cancer patients who undergo free flap reconstruction.

Objective: This study sought to quantify the deep venous thrombosis (DVT) incidence in head and neck cancer (HNC) patients undergoing free tissue transfer and to identify independent predictors of postoperative DVT. Materials and Methods: This is a cross-sectional study of the National Surgical Quality Improvement Program database from 2010 through 2020. The sample included all HNC surgical patients treated with free flap reconstruction. The study outcome was the presence of a DVT requiring treatment within 30 days of surgery. Univariate analyses were performed using chi-squared and independent t-tests. A multiple logistic regression model was created using all significant univariate predictors. Results: A total of 3954 patients were identified, of whom 53 (1.3%) experienced a postoperative DVT. The only medical comorbidity associated with DVT was COPD (RR = 2.7 [1.3, 5.4]; p < .01). Operative time longer than 9 hours (RR = 1.9 [1.0, 3.2]; p = .04) and length of stay longer than 10 days (RR = 1.9 [1.1, 3.2]; p = .02) were associated with greater DVT rates. In the multivariate analysis, only COPD (p < .01) and operative time (p = .02) were independently associated with DVT risk. The presence of a DVT was found to increase the relative risk of readmission (RR = 2.1 [1.2, 3.6]; p < .01) and non-home disposition (RR = 2.4 [1.7, 3.5]; p < .01). Conclusions: The incidence of DVT in HNC free flap patients was comparable to what has been reported in the general population of HNC surgery patients. Operative time >9 h and COPD history were independent risk factors for DVT in this subset of patients. Symptomatic DVTs necessitating treatment were accompanied by poorer post-hospitalization outcomes. Level of Evidence: Level 3.

Immune Cell Deconvolution Reveals Possible Association of γδ T Cells with Poor Survival in Head and Neck Squamous Cell Carcinoma.

(1) Background: The role of rare immune cell subtypes in many solid tumors, chief among them head and neck squamous cell carcinoma (HNSCC), has not been well defined. The objective of this study was to assess the association between proportions of common and rare immune cell subtypes and survival outcomes in HNSCC. (2) Methods: In this cohort study, we utilized a deconvolution approach based on the CIBERSORT algorithm and the LM22 signature matrix to infer proportions of immune cell subtypes from 517 patients with untreated HPV-negative HNSCC from The Cancer Genome Atlas. We performed univariate and multivariable survival analysis, integrating immune cell proportions with clinical, pathologic, and genomic data. (3) Results: We reliably deconvolved 22 immune cell subtypes in most patients and found that the most common immune cell types were M0 macrophages, M2 macrophages, and memory resting CD4 T cells. In the multivariable analysis, we identified advanced N stage and the presence of γδ T cells as independently predictive of poorer survival. (4) Conclusions: We uncovered that γδ T cells in the tumor microenvironment were a negative predictor of survival among patients with untreated HNSCC. Our findings underscore the need to better understand the role of γδ T cells in HNSCC, including potential pro-tumorigenic mechanisms, and whether their presence may predict the need for alternative therapy approaches.

The Role of Fluorescent Angiography in Free Flap Reconstruction of the Head and Neck.

OBJECTIVES: Highlight the use of fluorescent angiography in free flap reconstruction of the head and neck. Qualify how fluorescent angiography can be selectively added to management paradigms for head and neck free flap reconstruction. METHODS: Retrospective chart review of 993 free flaps completed from the time the SPY Elite® system first became available at our institution between September 2013, until August 2020. Cases that used the SPY Elite® system were grouped into three broad categories: evaluation during initial flap harvest while still attached to the donor site, evaluation after anastomosis in the head and neck area, and evaluation post-operatively for questionable flap viability. RESULTS: The SPY Elite® system was used in 64 cases. Forty flaps were evaluated intraoperatively during initial harvest and before anastomosis to the head and neck area. Of these, 20 had signs of poor perfusion of the entire skin paddle, 12 had large myogenous or skin flaps with questionable perfusion of the distal aspect, and 8 were evaluated for other reasons. In this group the use of SPY Elite® changed the management of the patient in 20 cases (50%). Ten flaps were evaluated intraoperatively after anastomosis to the head and neck to ascertain adequate flow to the entire flap. In this group management was changed in two (20%). Fourteen flaps were evaluated 3-5 days post operatively due to suspected failure of a component. In five cases (36%), the use of SPY Elite® determined management with either trimming or discarding the flap. CONCLUSION: Assessment of flap perfusion via fluorescent angiography during initial flap harvest or when flap compromise is suspected post-operatively can guide decision making in free flap reconstruction of the head and neck and can be added to existing planning and management paradigms. LEVEL OF EVIDENCE: 4 Laryngoscope, 133:1388-1393, 2023.

Tracheostomy Outcomes in Patients With COVID-19 at a New York City Hospital.

Objective: Tracheostomies have been performed in patients with prolonged intubation due to COVID-19. Understanding outcomes in different populations is crucial to tackle future epidemics. Study Design: Prospective cohort study. Setting: Tertiary academic medical center in New York City. Methods: A prospectively collected database of patients with COVID-19 undergoing open tracheostomy between March 2020 and April 2020 was reviewed. Primary endpoints were weaning from the ventilator and from sedation and time to decannulation. Results: Sixty-six patients underwent tracheostomy. There were 42 males (64%) with an average age of 62 years (range, 23-91). Patients were intubated for a median time of 26 days prior to tracheostomy (interquartile range [IQR], 23-30). The median time to weaning from ventilatory support after tracheostomy was 18 days (IQR, 10-29). Of those sedated at the time of tracheostomy, the median time to discontinuation of sedation was 5 days (IQR, 3-9). Of patients who survived, 39 (69%) were decannulated. Of those decannulated before discharge (n = 39), the median time to decannulation was 36 days (IQR, 27-49) following tracheostomy. The median time from ventilator liberation to decannulation was 14 days (IQR, 8-22). Thirteen patients (20.0%) had minor bleeding requiring packing. Two patients (3%) had bleeding requiring neck exploration. The all-cause mortality rate was 10.6%. No patients died of procedural causes, and no surgeons acquired COVID-19. Conclusion: Open tracheostomies were successfully and safely performed at our institution in the peak of the COVID-19 pandemic. The majority of patients were successfully weaned from the ventilator and sedation. Approximately 60% of patients were decannulated prior to hospital discharge.

Conditional and Overall Disease-Specific Survival in Patients With Paranasal Sinus and Nasal Cavity Cancer: Improved Outcomes in the Endoscopic Era.

BACKGROUND: The management of paranasal sinus and nasal cavity malignancies has evolved significantly with the development of advanced endoscopic techniques and improvements in adjuvant therapy. We sought to characterize both disease-specific survival (DSS) and 5-year conditional disease-specific survival (CDSS, the change in life expectancy with increasing survivorship) for sinus malignancies diagnosed before and after the year 2000. METHODS: Patients diagnosed with sinus and nasal cavity cancer between 1973-2015 were extracted from the Surveillance, Epidemiology, End Results (SEER) registry. Kaplan-Meier analysis for DSS was stratified by year of diagnosis before and after 2000. Cox-proportional hazards models of DSS controlling for stage, age, and year of diagnosis were generated. CDSS was calculated using Cox-regression models stratified by stage. RESULTS: We analyzed 10,535 patients. Diagnosis after the year 2000 was independently associated with improved DSS (HR:0.81, 95% CI: 0.75-0.87, P < .001) after controlling for age and stage. After stratifying by stage, diagnosis after year 2000 was associated with improved DSS for localized (HR:0.71, 0.59-0.86, P < .001) malignancies, regional (HR: 0.86, 0.78-0.94, P = .001) and distant malignancies (HR 0.74, 0.63-0.87, P < .001). CDSS improved with increasing survivorship for all stages of sinus and nasal cavity cancer, and those diagnosed after 2000 had improved CDSS compared to those diagnosed before 2000. Descriptively, the association of year of diagnosis with CDSS diminished with increasing survivorship for localized cancers, but was consistent for other stages. CONCLUSION: For paranasal sinus and nasal cavity malignancies, year of diagnosis independently influences both DSS and CDSS. Improved survival is likely due to advances in both surgical and adjuvant treatments. To our knowledge, this study is the first to examine CDSS for these malignancies.

Targeted Neoadjuvant Intra-arterial Chemotherapy in Lacrimal Gland Adenoid Cystic Carcinoma: A Histological Correlation Using Apoptotic Tumor Markers.

Neoadjuvant intra-arterial cytoreductive chemotherapy is used for the treatment of lacrimal gland adenoid cystic carcinomas (ACC) to improve outcomes in this condition with an otherwise dismal prognosis. We share our experience in the management of an advanced case of ACC using a novel, highly targeted intra-arterial cytoreductive chemotherapy delivery technique involving both the internal and external carotid circulation, with an attempt to correlate the effect histologically. Refinement of the chemotherapy delivery using the tumor's vascular anatomy and appropriate blood vessel selection may lead to future globe sparing procedures without compromising survival.

Venous Flow Coupler in Head and Neck Free Flap Reconstruction.

OBJECTIVE: To describe the utility of venous flow couplers in monitoring free tissue flaps in the immediate postoperative setting. STUDY DESIGN: Retrospective case series. SETTING: Otolaryngology department at a single tertiary care institution. METHODS: A retrospective case series of free flap reconstructions in which venous flow couplers were employed to supplement flap monitoring. All free flap cases performed over the past 4 years were reviewed. Inclusion criteria were venous flow coupler and arterial flow Doppler monitored for 5 days postoperatively. RESULTS: From July 2014 through May 2018, the venous flow coupler was used with the arterial flow Doppler and clinical monitoring in 228 cases. Eleven cases did not meet criteria for inclusion; thus, 217 cases were analyzed. Twenty cases (9.2%) returned to the operating room with concern for flap compromise, and 16 were salvaged. The combination of venous flow coupler and arterial flow Doppler identified 19 of these flaps. Venous flow couplers identified 5 compromised flaps before there was an arterial signal change, and all were salvaged. Additionally, there was a 24.1% false-positive rate when 2 venous flow couplers were used in parallel. For the venous flow coupler, the positive predictive value was 64.3% and the negative predictive value, 98.9%. The false-positive rate in the series was 5.1%. The sensitivity was 90% and the specificity, 94.9%. CONCLUSION: The venous flow coupler is able to detect venous thrombosis in the absence of arterial thrombosis and may contribute to improved flap salvage rates.

A novel neck brace to characterize neck mobility impairments following neck dissection in head and neck cancer patients.

Objective: This article introduces a dynamic neck brace to measure the full range of motion (RoM) of the head-neck. This easy-to-wear brace was used, along with surface electromyography (EMG), to study changes in movement characteristics after neck dissection (ND) in a clinical setting. Methods: The brace was inspired by the head-neck anatomy and was designed based on the head-neck movement of 10 healthy individuals. A 6 degrees-of-freedom open-chain structure was adopted to allow full RoM of the head-neck with respect to the shoulders. The physical model was realized by 3D printed materials and inexpensive sensors. Five subjects, who underwent unilateral selective ND, were assessed preoperative and postoperative using this prototype during the head-neck motions. Concurrent EMG measurements of their sternocleidomastoid, splenius capitis, and trapezius muscles were made. Results: Reduced RoM during lateral bending on both sides of the neck was observed after surgery, with a mean angle change of 8.03° on the dissected side (95% confidence intervals [CI], 3.11-12.94) and 9.29° on the nondissected side (95% CI, 4.88-13.69), where CI denotes the confidence interval. Axial rotation showed a reduction in the RoM by 5.37° (95% CI, 2.34-8.39) on the nondissection side. Neck extension showed a slight increase in the RoM by 3.15° (95% CI, 0.81-5.49) postoperatively. Conclusions: This brace may serve as a simple but useful tool in the clinic to document head-neck RoM changes in patients undergoing ND. Such a characterization may help clinicians evaluate the surgical procedure and guide the recovery of patients.

Shift in the timing of microvascular free tissue transfer failures in head and neck reconstruction.

OBJECTIVE: Analyze the cause and significance of a shift in the timing of free flap failures in head and neck reconstruction. STUDY DESIGN: Retrospective multi-institutional review of prospectively collected databases at tertiary care centers. METHODS: Included consecutive patients undergoing free flap reconstructions of head and neck defects between 2007 and 2017. Selected variables: demographics, defect location, donor site, free flap failure cause, social and radiation therapy history. RESULTS: Overall free flap failure rate was 4.6% (n = 133). Distribution of donor tissue by flap failure: radial forearm (32%, n = 43), osteocutaneous radial forearm (6%, n = 8), anterior lateral thigh (23%, n = 31), fibula (23%, n = 30), rectus abdominis (4%, n = 5), latissimus (11%, n = 14), scapula (1.5%, n = 2). Forty percent of flap failures occurred in the initial 72 hours following reconstruction (n = 53). The mean postoperative day for flap failure attributed to venous congestion was 4.7 days (95% confidence interval [CI], 2.6-6.7) versus 6.8 days (CI 5.3-8.3) for arterial insufficiency and 16.6 days (CI 11.7-21.5) for infection (P < .001). The majority of flap failures were attributed to compromise of the arterial or venous system (84%, n = 112). Factors found to affect the timing of free flap failure included surgical indication (P = .032), defect location (P = .006), cause of the flap failure (P < .001), and use of an osteocutaneous flap (P = .002). CONCLUSION: This study is the largest to date on late free flap failures with findings suggesting a paradigm shift in the timing of flap failures. Surgical indication, defect site, cause of flap failure, and use of osteocutaneous free flap were found to impact timing of free flap failures. LEVEL OF EVIDENCE: 4 Laryngoscope, 130:347-353, 2020.

Outcomes and cost implications of microvascular reconstructions of the head and neck.

BACKGROUND: Critical review of current head and neck reconstructive practices as related to free flap donor sites and their impact on clinical outcomes and cost. METHODS: Retrospective multicenter review of free tissue transfer reconstruction of head and neck defects (n = 1315). Variables reviewed: defect, indication, T classification, operative duration, and complications. A convenience sample was selected for analysis of overall (operative and inpatient admission) charges per hospitalization (n = 400). RESULTS: Mean charges of hospitalization by donor tissue: radial forearm free flap (RFFF) $127 636 (n = 183), osteocutaneous RFFF (OCRFFF) $125 456 (n = 70), anterior lateral thigh $133 781 (n = 54), fibula $140 747 (n = 42), latissimus $208 890 (n = 24), rectus $169 637 (n = 18), scapula $128 712 (n = 4), and ulna $110 716 (n = 5; P = .16). Mean operative times for malignant lesions stratified by T classification: 6.9 hours (±25 minutes) for T1, 7.0 hours (±16 minutes) for T2, 7.3 hours (±17 minutes) for T3, and 7.8 hours (±11 minutes) for T4 (P < .0001). Complications correlated with differences in mean charges: minor surgical ($123 720), medical ($216 387), and major surgical ($169 821; P < .001). Operations for advanced malignant lesions had higher mean charges: T1 lesions ($106 506) compared to T2/T3 lesions ($133 080; P = .03) and T4 lesions ($142 183; P = .02). On multivariate analysis, the length of stay, operative duration, and type a postoperative complication were factors affecting overall charges for the hospitalization (P < .018). CONCLUSION: Conclusion: The RFFF and OCRFFF had the lowest complication rates, length of hospitalization, duration of operation, and mean charges of hospitalization. Advanced stage malignant disease correlated with increased hospitalization length, operative time, and complication rates resulting in higher hospitalization charges.

Combined endoscopic and transcervical approach for free flap reconstruction of nasopharyngeal and clival defects: A case report.

We report a case during which a new method of reconstruction for a nasopharyngeal and skull base defect was successfully performed. A 45-year-old female with granulomatosis with polyangiitis presented with computed tomography (CT) findings demonstrative of chronic clival and cervical spine osteomyelitis secondary to nasopharyngeal destruction. The posterior nasopharyngeal defect, evident as a wide area of mucosal erosion exposing the clivus centrally, was successfully reconstructed with an anterior serratus muscle-free tissue transfer via both transcervical and endoscopic transnasal approaches utilizing a laparoscopic fixation device, a previously unreported method for free flap inset, to secure the free flap. The patient tolerated this well and no major complications were encountered. At 2-year follow-up, the patient was without signs of cerebrospinal fluid leak or sequelae of infectious complications, including meningitis and osteomyelitis. A combined transcervical and endoscopic transnasal approach using a laparoscopic fixation device for free flap inset can be an effective method to reconstruct posterior nasopharyngeal defects in those patients whom local reconstructive options are not available.

Osteocutaneous radial forearm free flap in nonmandible head and neck reconstruction.

BACKGROUND: The osteocutaneous radial forearm free flap (RFFF) is a versatile flap primarily used to reconstruct composite defects involving the mandible. The purpose of this study was to describe our experience with this flap for nonmandible reconstruction. METHODS: All patients undergoing nonmandible osseous reconstruction with free-tissue transfer were reviewed. Patients with osteocutaneous RFFF reconstructions were evaluated. The retrospective review of all osteocutaneous RFFFs was performed from 1998 to 2014. RESULTS: One hundred forty-two nonmandible osseous reconstructions were performed. Twenty-five patients underwent nonmandible osteocutaneous RFFF reconstruction. Eleven patients failed previous nonmicrovascular reconstruction. Reconstruction was for defects of the: palatomaxillary complex (n = 15), orbitomaxillary complex (n = 4), nasomaxillary complex (n = 4), larynx (n = 1), and clavicle (n = 1). There were no flap compromises. Postoperative complications included: 2 partial intraoral dehiscences; 1 recipient-site infection; and 1 seroma. Eight reconstructions required secondary procedures to improve functional and/or cosmetic outcomes. CONCLUSION: The osteocutaneous RFFF is a robust flap that can be used to reconstruct composite defects involving bone and soft-tissue beyond the mandible.

Effect of Overlapping Operations on Outcomes in Microvascular Reconstructions of the Head and Neck.

Objective To compare outcomes after microvascular reconstructions of head and neck defects between overlapping and nonoverlapping operations. Study Design Retrospective cohort study. Setting Tertiary care center. Subjects and Methods Patients undergoing microvascular free tissue transfer operations between January 2010 and February 2015 at 2 tertiary care institutions were included (n = 1315). Patients were divided into 2 cohorts by whether the senior authors performed a single or consecutive microvascular reconstruction (nonoverlapping; n = 773, 59%) vs performing overlapping microvascular reconstructions (overlapping; n = 542, 41%). Variables reviewed were as follows: defect location, indication, T classification, surgical details, duration of the operation and hospitalization, and complications (major, minor, medical). Results Microvascular free tissue transfers performed included radial forearm (49%, n = 639), osteocutaneous radial forearm (14%, n = 182), anterior lateral thigh (12%, n = 153), fibula (10%, n = 135), rectus abdominis (7%, n = 92), latissimus dorsi (6%, n = 78), and scapula (<1%, n = 4). The mean duration of the overlapping operations was 21 minutes longer than nonoverlapping operations ( P = .003). Mean duration of hospitalization was similar for nonoverlapping (9.5 days) and overlapping (9.1 days) cohorts ( P = .39). There was no difference in complication rates when stratified by overlapping (45%, n = 241) and nonoverlapping (45%, n = 344) ( P = .99). Subset analysis yielded similar results when minor, major, and medical complications between groups were assessed. The overall survival rate of free tissue transfers was 96%, and this was same for overlapping (96%) and nonoverlapping (96%) operations ( P = .71). Conclusions Patients had similar complication rates and durations of hospitalization for overlapping and nonoverlapping operations.

Secondary free-flap reconstruction following ablation for acute invasive fungal sinusitis.

OBJECTIVE: Acute invasive fungal sinusitis (AIFS) is a frequently fatal infection for which extensive and debilitating surgical debridement is a mainstay of therapy. Resulting defects are often composite in nature, mandating free tissue-transfer reconstruction. Outcomes data for free flap reconstruction are limited. The purpose of this study was to examine surgical outcomes and survival in patients undergoing free flap transfer following invasive fungal sinusitis. STUDY DESIGN: Retrospective case series. METHODS: Between 1995 and 2015, patients undergoing operative debridement for AIFS were identified. Surgical records were used to identify survivors of acute infection who subsequently underwent free flap reconstructive surgery. Patient demographics, cause of immune compromise, defect description, flap type, perioperative complications, indications for revision surgery, functional outcomes, and long-term survival were reviewed. RESULTS: Forty-four patients were treated for AIFS, of those, 30 (68%) survived acute infection. Ten patients underwent maxillectomy, six with orbital exenteration, and were designated candidates for reconstruction. Eight patients underwent reconstruction. Median time from debridement to reconstruction was 67.5 days. Flap types included latissimus dorsi, scapula, anterolateral thigh, rectus, radial forearm, and fibula. Median follow-up was 7.7 months. No perioperative complications were encountered, and all subjects remained disease-free, able to speak and eat normally without prosthetic supplementation. Seven patients (87%) are currently alive. CONCLUSION: Reconstruction of defects left by invasive fungal sinusitis using free-tissue transfer resulted in successful flap survival, with no disease recurrence for all defects and flap types reviewed. Survivors of AIFS are able to tolerate midface reconstruction, with favorable functional outcomes and survival rates. LEVEL OF EVIDENCE: 4. Laryngoscope, 127:815-819, 2017.

High-grade malignant transformation of a radiation-naïve nasopharyngeal angiofibroma.

BACKGROUND: Nasopharyngeal angiofibromas are typically considered benign vascular neoplasms, with descriptions of high-grade sarcomatous change found only in lesions with prior radiotherapy. METHODS AND RESULTS: We describe the first reported case of high-grade malignant change in a nasopharyngeal angiofibroma naive to radiation. A 45-year-old man presented with left-sided nasal congestion and fullness and was found to have a left-sided nasopharyngeal mass with intracranial extension on CT scan. A biopsy of the mass revealed nasopharyngeal angiofibroma. The patient opted for MRI surveillance, which revealed interval growth 3 years later. Decompression surgery revealed only angiofibroma, but resection 9 months later demonstrated high-grade sarcoma and concomitant angiofibroma. The patient had residual disease which progressed through chemoradiation, and is now pursuing clinical trial enrollment. CONCLUSION: Malignant transformation of nasopharyngeal angiofibroma is extremely rare. As highlighted by this report, high-grade undifferentiated lesions may arise in tumors without previous radiation. © 2016 Wiley Periodicals, Inc. Head Neck 38: E2425-E2427, 2016.

Transoral robotic retropharyngeal node dissection.

BACKGROUND: Surgical access to metastases in the retropharyngeal lymph nodes (RPLNs) could be difficult. Transoral robotic surgery (TORS) can be utilized to access RPLNs. The purpose of this study was to describe a TORS approach to RPLN dissection. METHODS: A case series of patients undergoing RPLN dissection by TORS was conducted and compared to matched controls (1:2). RESULTS: Twelve patients underwent robotic RPLN dissection. Median age was 63 years (range, 43-73 years). Pathology was oropharyngeal squamous cell carcinoma (SCC) in 9 patients and papillary thyroid cancer (PTC) in 3 patients. The feeding tube dependence duration was 12 days (range, 1-46 days) on average. Complications occurred in 8 patients (66%); most commonly, aspiration pneumonitis in 6 patients. In comparison to the matched controls (24), there was no difference in length of stay or feeding tube dependence. Complications were higher in patients with oropharyngeal SCC. CONCLUSION: TORS is feasible for accessing RPLNs. The procedure is well tolerated in patients with PTC; whereas patients with oropharyngeal SCC are at increased risk of complications. © 2015 Wiley Periodicals, Inc. Head Neck 38: E981-E986, 2016.

An evidence-based algorithm for intraoperative monitoring during cochlear implantation.

OBJECTIVE: To generate an evidence-based algorithm for the use of intraoperative testing during cochlear implantation (CI). STUDY DESIGN: Retrospective review. SETTING: Tertiary referral center. PATIENTS: A total of 277 children (aged 6 mo to 17 yr) and adults 18 years and older with normal cochlear anatomy who underwent primary and revision cochlear implantation at a single center between 2005 and 2010 were included. INTERVENTION: Intraoperative electrophysiologic monitoring and intraoperative Stenver's view plain film radiography. MAIN OUTCOME MEASURE: Intraoperative testing included the following: 1) individual electrode impedance measurements; 2) neural response telemetry (tNRT) levels for electrodes E20, E15, E10, and E5; and 3) plain film radiograph assessment of electrode position. RESULTS: No patient demonstrated abnormalities on all 3 modalities. Open or short electrodes on impedance testing were found in 6% of patients; half of these normalized when remeasured. Absent tNRT responses on 1 or more electrodes occurred in 14% of patients, although complete lack of response was rare (1.4%) and did not correlate with a dysfunctional device. Spread of excitation was performed in 1 patient and was consistent with a tip rollover. Intraoperative radiography identified tip-rollover and extracochlear electrode placement in all cases (n = 5, 1.8%) and prompted the use of the backup device. CONCLUSION: Immediate intraoperative determination of device functionality and optimal electrode placement is advantageous. Of the modalities tested, including electrode impedance, tNRT, and plain radiograph, only the radiographic results impacted intraoperative surgical decision making and led to the use of the backup device.