FCOM 2022 Poster Submissions

A perilymphatic fistula is an abnormal communication between the middle ear or mastoid and the inner ear. Trauma is a well-documented etiology of this pathology. We discuss a 10 yr old male who presented with unilateral hearing loss, vertigo and tinnitus after getting hit with a baseball to his left ear. The patient underwent an intratympanic autologous blood patch with complete resolution of his complaints. Although, intratympanic autologous blood patches have limited data, the procedure appears to be a cost-effective option to pursue before surgical intervention.

Introduction
The subscapular system is a highly versatile donor site to obtain free tissue for both bony and soft tissue head & neck reconstruction. Traditional methods of harvesting subscapular flaps required intraoperative repositioning of the patient to a lateral decubitus position, which significantly increased the operative time and prevented simultaneous harvesting of the flap. Various surgical teams have described advances on this technique, but these methods are dependent on either added assistants, a secondary sterile Mayo stand, or a somewhat bulky Spider Limb Positioner® placed on the contralateral side of the table from the harvest site. To overcome these limitations, we have introduced the Trimano Fortis limb positioning system in our practice.

Methods
Single institution retrospective chart review and analysis of patients between 2020 and 2022 that underwent a subscapular system free flap with use of the Trimano Fortis limb positioning system. Forty-one patients in total were reviewed. Variables regarding age, procedure indications, cancer staging, bony defects, anesthesia time, hospital length of stay, and postoperative complications were recorded.

Results
68% of patients were managed for an active cancer (46% oral cavity primary) with all these staged as with T4a or T4b utilizing the AJCC 8th edition system. Median total anesthesia time was 567 minutes ranging from 456 – 753 minutes depending on the extent of resection and complexity of the surgical defect. Median hospital of stay was seven days. Five patients developed a major surgical site complications including 4 with pharyngocutaneous fistula formation and 1 with culture confirmed wound infection. There was one case of partial free flap failure and no cases of total free flap failure in this series.

Discussion
At our institution, application of this positioning system is in part responsible for making the subscapular system the preferred reconstruction for mandibulectomy/maxillectomy defects unless a large volume (>10cm) of bone or dental implantation is expected. It has thus allowed us to fully take advantage of the subscapular system, facilitating a two-team approach, decreasing operative times to match that of other bony free flaps, limits the number of required intraoperative assistants, and simplifies flap harvest to ensure consistent perioperative results.

Background: In recent years, technology has drastically advanced to accurately and efficiently visualize pathologies in human anatomical structures. Computed tomography (CT) segmentation is a method of generating 3-dimensional (3D) models of anatomical structures of interest. Virtual reality (VR) establishes an excellent environment for clinicians to visualize and directly interact with 3D CT image volumes and segmented anatomical models. Surgical planning for complex airway stenosis poses important challenges for airway surgeons. While soft tissue stenosis can often be managed endoscopically, framework deformities might need open surgical intervention for laryngotracheal reconstruction.

Objective: We hypothesized that a method to segment human airways from clinical cases and import them into a case presentation environment in VR could be developed and used to modelize and visualize complex airway stenosis for efficient surgical planning.

Methods: One normal and two pathological airways modeled from head, neck, and chest CT scans at a slice thickness of 0.625 mm were processed. A multidisciplinary team composed of airway surgeons, VR engineers, and radiologists collaborated to create a clinically relevant, anatomically accurate VR rendering and explanatory Narrations of the 3 clinical cases.

Results: Segmentation and post-processing was completed in the Mimics Innovation Suite v24 from Materialise. Structures were segmented from the level of bifurcation of common carotid arteries to the level of bifurcation of the main bronchi, including cartilaginous and bony airway structures, vessels, and soft tissues. The segmented laryngeal framework and surrounding anatomical structures were then post-processed into 3D image volumes and imported into syGlass, a VR software. Direct visualization and free manipulation of these 3D airway models within the VR environment provided improved geometrical and anatomical details compared to traditional 2-dimensional (2D) CT. This allowed medical image data to be more readily understandable to non-radiologists and surgeons alike, as only using 2D data limits the details that can be gleaned from the dataset. Then, specialized presentation and active learning tools developed for scientific communication using the VR environment permitted creation of Narrations to explain pathological cases. Users could visualize superimposed segmented models and VR scans, and explore either or both by altering opacity settings and using a variety of tools including measuring, sectioning, and resectioning.

Conclusion: The method to segment human airways from clinical cases used in this paper shows a potential in the use of 3D airway modeling and VR in clinical practice for description and surgical planning of complex airways. Intricate collaboration between VR engineers, radiologists, 3D modeling experts and airway surgeons was key to create a clinically relevant and radiologically accurate model. Further work is needed to validate use of these models in clinical practice and patient education.

Background: Interventional strategies for dealing with microvascular free flap failure are varied among institutions and even individual surgeons. This systematic review aims to identify the published methods for salvaging a failing free flap and provide surgeons with a comprehensive toolset for successful intervention.
Methods: A title and abstract search of the PubMed, Embase, and Web of Science databases was performed. 1,694 abstracts were screened by three reviewers according to Prisma guidelines.
Results: 62 full text articles meeting inclusion criteria detailed techniques which were separated into the categories of thrombectomy, thrombolysis, leech therapy, vascular fistula, and an “other” category outlining techniques which did not fit into the prior framework.
Conclusions: Assessment of the efficacy of individual salvage techniques is limited due to limited empirical data. Approach to successful salvage should be based on timely identification of flap compromise, followed by the implementation of one or several of the aforementioned techniques.

Stricture formation is a serious complication following pharyngeal reconstruction. These strictures can be life-threatening and can severely impact quality of life. We have reviewed the existing literature on surgical risk factors linked to neopharyngeal stricture formation. Intraoperative preventative measures reconstructive surgeons should consider are also discussed. Finally, we will describe the evaluation and management of pharyngoesophageal strictures, including the challenges and options when dealing with refractory strictures.

Recent literature shows that tumor volume in T3 laryngeal cancer (LC) can predict response to radiation therapy. Patients with tumors > 2.5cc have inferior long-term disease-free status and require increased rates of salvage laryngectomy. The effect of tumor volume on survival after primary surgery is unknown. The aim of this study was to determine to the effect of tumor volume on survival outcomes in patients undergoing primary and salvage total laryngectomy (TL). Patients with LC undergoing primary or salvage TL were included. Prospective data base was used to extract patient data and preoperative CT-scans. 2 radiologists reviewed each scan to determine tumor volume by an established protocol. Survival outcomes were determined by Kaplan-Meier and Cox-regression analysis. 117 patients were included. 3 (2.6%) had T1-T2 disease, 41 (35%) had T3 disease, 72 (61.5%) had T4 disease and 1 (0.9%) had unknown T stage. Average tumor volume was 22.6cc with a median of 17.3cc (range: 1.8-166cc). Higher tumor volume was positively correlated with Body Mass Index (BMI) and smoking history. Higher tumor volume, BMI, Charlson Comorbidity Index (CCI), and perineural invasion (PNI) were found to decrease overall survival (p

Background. Sialorrhea, also known as excessive salivation, is considered abnormal beyond four years of age. Sialorrhea severity is best measured using a combination of quantitative and qualitative metrics to guide clinical decision making. Severe cases warrant intervention to improve patient quality of life and reduce caretaker burden.

Objective. The primary aim of this study is to review the five major forms of sialorrhea management ranging from least-to-most invasive: oral-motor therapy, anticholinergic medications, botulinum neurotoxin, sialendoscopy sclerotherapy, and surgical intervention.

Data Sources and Review Methods. An electronic literature review identified articles through a comprehensive search of sialorrhea management in pediatric patients in Cambridge Scientific Abstracts, EMBASE, PubMed, and Web of Science.

Conclusions and Implications for Practice. Sialorrhea management starts with more conservative approaches. Viable candidates begin with oral-motor therapy. Anticholinergic medications can decrease saliva production, but adverse side effects may outweigh benefits. Botulinum neurotoxin injection of the salivary glands decreases salivary flow rate; however, relief is transient and thus requires multiple treatments. Sialendoscopy sclerotherapy is the latest treatment option that shows promising results. Surgical intervention is reserved as a treatment option of last resort for patients who suffer from severe sialorrhea due to potential adverse consequences, which include airway swelling/obstruction, facial nerve paralysis, postoperative hemorrhage, and xerostomia with its downstream effects. In conclusion, this review found that the underlying cause and severity of sialorrhea dictate the approach to management.

Background: Olfactory disturbances including anosmia and parosmia are unique features of SARS-CoV-2 infection with high positive predictive value. Change in olfaction appears to be the consequence of multiple parallel processes including conductive and obstructive anosmia, destruction of nasal cilia and olfactory sensory neurons, and retrograde destruction of higher-order olfactory neural processes. The global pooled estimate for olfactory disturbance among patients with a positive RT-PCR is approximately 40%. To date, there has been no investigation of regional differences in the prevalence of olfactory disturbance in SARS-CoV-2 infection, and no analysis of this sequelae in the southern US.

Methods: A retrospective cohort analysis was performed using the Informatics for Integrating Biology and the Bedside data tool at University of Florida Shands Hospital (i2b2). Outcomes of interest were “SARS coronavirus 2 RNA” and “R43.0 anosmia” OR “R43.1 parosmia”. Covariates were gender (female, male, not recorded, unknown), race (American Indian, Black Hispanic, Black or African American, Hispanic, Indian, Native Hawaiian, White, White Hispanic, Multiracial, and other), and age (0-9, 10-17, 18-34, 35-44, 45-54, 55-64, 65-74, 75-84, 85+).

Results: 8572 patients with COVID-19 were identified, of which 229 (2.8%) had olfactory disturbance. Among patients with olfactory disturbance, 157 (68.9%) were female and the mean age was 31.7 years (95% CI: 17.8- 45.6). Less than 3 patients were American Indian, Black Hispanic, Hispanic, Indian, Native Hawaiian, White Hispanic, or Multiracial. 62 (27.1%) were Black or African American, 141 (61.6%) were White, and 16 (7.0%) were other. Less than 3 patients were 0-9 years, 12 (5.2%) were 10-17 years, 119 (52%) were 18-34 years, 31 (13.5%) were 35-44 years, 26 (11.4%) were 45-54 years, 18 (7.9%) were 55-64 years, 11 (4.8%) were 65-74 years, 5 (2.2%) were 75-84 years, and less than 3 were 85+ years. Prevalence of anosmia and parosmia was more than double in female patients compared to male patients. R² for age group vs. olfactory disturbance diagnosis was .2382.

Conclusion: In this study we found the prevalence of anosmia and parosmia among patients with a positive RT-PCR at University of Florida Shands was much lower than global pooled estimates. Olfactory disturbance in this study reflected age-dependent anosmia, with patients 75-84 years reflecting the lowest prevalence. Given these findings we conclude that while anosmia is regarded as an early marker of COVID-19 infection, it may not be as reliable of a predictor in elderly populations in the southern United States.

Background: Gaps embedded in noise (GIN) have been used as acoustic stimulus to evaluate the auditory temporal processing of different study populations such as in subjects with central auditory processing disorders (CAPD). Since GIN are very short as miliseconds (ms), they have been used to evaluate temporal resolution which is defined as the ability to detect small changes in sound over time, or slight discontinuities in ongoing stimuli. Poor temporal resolution has been shown to correlate with speech recognition difficulties. The gap detection threshold (GDT) is defined as the shortest gap that can be perceived in an otherwise continuous background stimulus. Electrophysiological assessment of GIN has focused mainly on Late Latency Responses requiring awake alert subjects (humans or animals). As rat models are commonly employed to understand the molecular mechanisms underlying auditory and neurological disorders, there is a need to develop techniques to determine central auditory processing (CAP) in experimental animal models.

Methods: We developed a method to determine the Objective Gap Detection Threshold (OGDT) in rats. QSSR elicited by noise modulated by 40Hz gaps of different durations were analyzed in time and frequency domains using wild-type (WT) and rat model of autism. The detection was performed in frequency domain, by applying the Hotelling’s T2 test to the 40Hz complex fundamental frequency component. The OGDT is estimated by analyzing the confidence ellipses of the 40Hz spectral component.

Results: When the confidence ellipses (p=0.05) contain the origin of the complex plane, we observed that the subject is not significantly detecting the noise gap. We observed that the rats were detecting noise gaps of 12, 10 and 8ms and not detecting the 6ms gap. We also observed the “vanishing” of response into the background noise when a 4ms noise gap is applied. The 5ms OGDT result was verified by the statistical T2 test and is consistent with the previous animal studies with awake rats. The OGDT values were significantly increased in our rat model of autism in agreement with findings observed in humans having neurological disorders.

Conclusions: We have developed an electrophysiological method to determine GDT as a measure of CAPD in an anesthetized rat model. This technique eliminates the need for being alert and awake during the test bringing a new dimension especially in animal experiments regarding central auditory evaluation. The availability of novel objective techniques to determine CAPD will help in its early detection in affected individuals leading to early intervention and hence better clinical outcomes.

Background: There is a growing need to develop prophylactic and therapeutic interventions to prevent loss of residual hearing post-cochlear implantation. During cochlear implantation, the initiation of the electrode insertion trauma (EIT) triggers the activation of oxidative stress, apoptosis and inflammatory pathways that can damage sensory cells and consequently lead to the loss of residual hearing. Preserving these sensory cells by blocking the activation of these host pathways can improve hearing preservation and allows implanted individuals to benefit from better hearing outcomes. The aim of this study was to investigate the effect of Taurodeoxycholic acid (TDCA) on the preservation of the residual hearing in a preclinical animal model of cochlear implantation.

Method: Animals were divided into various groups. In first group, animals were implanted unilaterally. In second group, TDCA was applied on the round window membrane before cochlear implantation followed by insertion of the electrode. The animals in third group served as vehicle control whereas naïve animals that were not subjected to treatment with TDCA and cochlear implantation served as the control group. Contralateral ear from each group also served as the control group. Hearing thresholds of animals in each group were determined by auditory brainstem recordings (ABRs). Cochleae harvested from animals in each group was subjected to histopathological examination to determine pathological manifestations. The organ of Corti was dissected and stained with FITC phalloidin to visualize and count the number of hair cells.

Results: Hearing thresholds were significantly lower after TDCA application than in the EIT group. The organ of Corti harvested from cochlea of implanted and TDCA treated animals subject showed a significantly higher number of hair cells after immunostaining compared to implanted animal alone. The molecular mechanisms behind otoprotection involved abrogation of activation of oxidative stress and caspase pathways.

Conclusion: The result of the present study suggests that TDCA provides otoprotection against cochlear implant trauma and can be explored for developing effective interventions. The availability of new interventions to prevent electrode insertion trauma holds great potential to promote hearing preservation and expanding indications of cochlear implantation.