Author: michael

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.

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.

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.

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:
Lingual tonsil hypertrophy (LTH) is known as a possible cause of persistent child obstructive sleep apnea after adenotonsillectomy, especially in patients with trisomy 21, but its role in chronic cough and exercise-induced shortness of breath in non-syndromic patients is less well-established. As such, lingual tonsillectomy is rarely performed. This study is a preliminary exploration of the role of lingual tonsils and subsequent lingual tonsillectomy in pediatric patients with chronic respiratory-related symptoms refractory to more traditional therapies.

Research question: In pediatric patients, does lingual tonsil hypertrophy result in upper airway obstruction and respiratory-related symptoms that can then be treated with lingual tonsillectomy?

Methods:
Ten children were referred by a pediatric pulmonologist with chronic upper airway symptoms (cough, throat-clearing, exercise-induced shortness of breath, and in some cases, a sensation of food sticking in the back of the throat when eating) unresponsive to traditional treatments, and for whom the only abnormal finding on flexible bronchoscopy was LTH. Endoscopic lingual tonsillectomy was subsequently performed, and the post-operative response was assessed.

Results:
The patients had chronic respiratory-related symptoms including for an average of 21.9 months. After surgery, the patients were subsequently followed for an average of 24.2 months. Nine of ten patients saw preoperative symptom resolution after surgery. One patient experienced symptom recurrence and LTH again after 1 year but has seen symptom resolution 14 months after surgical revision. One patient has been subsequently scheduled for palatine tonsillectomy due to symptom persistence 2 years later. There were no intraoperative complications and only one patient experienced mild and self-limited pharyngeal bleeding 8 days postoperatively.

Conclusion:
Lingual tonsillectomy proved to significantly resolve chronic respiratory-related symptoms when no other treatment had in this case series.

Discussion:
The resolution of respiratory-related symptoms after lingual tonsillectomy implicates LTH in difficult-to-treat symptoms, including chronic cough, throat-clearing, and exercise-induced shortness of breath. Other symptoms that were also frequently present were snoring, globus sensation, and a sensation of food sticking in the back of the throat when swallowing. Each patient was previously treated, unsuccessfully, for differential diagnoses such as laryngopharyngeal reflux, allergic rhinitis, vocal cord dysfunction and reactive airway disease. LTH is difficult to diagnose and may be overlooked, contributing to the commonplace chronicity of these respiratory symptoms. Though sample size is a limitation, this study suggests that the role of the lingual tonsils should not be overlooked in patients with these types of symptoms. Further studies with a larger sample size are required to further support the use of lingual tonsillectomy as treatment for these chronic upper airway symptoms.

Background: Gender recognition systems based on voice analysis use machine learning (ML) algorithms analyzing various acoustic features of human voices. Pitch or fundamental frequency (f0), and its derived statistical measures, has been described as a common acoustic feature to determine voice gender. However, many intrinsic variables such as age, ethnicity and spoken language amongst others can impact f0 and its ability to predict voice gender. Although various studies have analyzed voice gender recognition in single languages, there is no data comparing acoustic measures related to f0 in multiple languages and their effect on gender recognition by ML models.

Objective: The objective of this study was to analyze the effect of spoken language on statistical features of fundamental frequency (f0) and its impact on gender recognition by machine learning models. The secondary objective was to determine which features had greatest impact on gender recognition by ML models in a consistent manner across languages.

Methods: A human voice dataset was extracted from the Mozilla Common Voice Corpus 10.0. Eight acoustic measures related to pitch (minimum f0, first quartile f0, mean f0, median f0, third quartile f0, maximum f0, interquartile range f0 and standard deviation f0) were extracted and analyzed using two ML algorithms and an improve logistic regression model. Voice data was stratified by age, gender (male/female) and language spoken (English, Spanish, French, Chinese, and German). Acoustic features and their derivatives were calculated based on the acoustic periodicity detection algorithm of Boersma implemented in PRAAT. Waikato Environment for Knowledge Analysis Software (WEKA, GNU General Public License version 3.8.6) was used for machine learning analysis with three machine learning (ML) classifier being a multilayer perceptron (MLP), J48 decision tree (J48), and a logistic regression model with a ridge estimator using the seven statistical features and the label age. For each language, balanced and unbalanced scenarios were constructed. Furthermore, a Correlation-based Feature Subset Selection for Machine Learning implemented in the WEKA software, was used to identify the impact of isolated acoustic features on gender recognition to investigate which features were consistent across multiple languages.

Results: A total of 1,784,244 voice samples from 21,785 unique speakers were analysed (80.3 % of male and 19.7% of female). Spoken language distribution consisted of English speakers (51.6%) Spanish speakers (15.5 %), German speakers (14.9%), French speakers (13.9%) and Chinese speakers (4.1%). The ML models reached high accuracy (for balanced cases) and F1 measure (for unbalanced datasets) in detecting voice gender (above 85% in all cases). Balanced voice datasets showed higher accuracy for Spanish speakers (96.27%, while the English speakers had the lowest accuracy in gender recognition (93.41%). When using the unbalanced dataset, Spanish speakers achieved the highest F1 measure (Spanish 92.1%, Chinese 91.3%, English 91.0%, German 89.5% and French 87.9%).
Across all 8 acoustic features studied, features that impacted accuracy the most across all languages were first quartile f0, mean f0, median f0, and third quartile f0.

Conclusion: This study demonstrates the effect of spoken language on accuracy of gender recognition by machine learning algorithm. As voice is becoming a biomarker and used for identification, this work emphasizes the need for balanced and diverse datasets for voice AI models that have the potential to become multilingual.

Background: The incidence of skin cancer is rapidly increasing. With the general population living longer, providers are seeing an increase in scalp defects due to cutaneous malignancies. The resulting defects after skin cancer excision can cause significant functional and aesthetic complications. We describe a single staged technique for scalp reconstruction in three medically complex patient’s. This technique aims to cover exposed calvarium with soft tissue and restore soft tissue contour while minimizing anesthesia risks and donor site morbidity.

Methods: Two patients with recurrent squamous cell carcinoma of their scalp previously treated with wide local excision, local flap reconstruction and radiation therapy, underwent re-excision with outer table craniectomy, single staged peri-cranial rotational flaps, and split thickness skin grafts. Another patient with a recent diagnosis of cutaneous clear cell carcinoma underwent the same surgery for a large scalp defect following cancer resection. Peri-cranial rotational flaps were designed to cover exposed calvarium defects. Flaps were approximated with resorbable suture and a split thickness skin graft harvested from the anterior thigh was sutured over the defect.

Results: Surgical wounds were well healed at initial post-operative visit and both split thickness skin grafts were noted to have 100% integration. All patient’s continued to show excellent healing results during long-term follow up.

Conclusions: Single stage scalp reconstruction utilizing peri-cranial rotational flaps is an effective reconstruction option for large scalp defects with exposed calvarium, most commonly seen with advanced or recurrent cutaneous carcinoma. This reconstructive option minimizes anesthesia risks and significant donor site morbidity, making it an appealing alternative in medically complexed patient’s.

Metastatic lesions to the paranasal sinuses and skull base are overall rare but carry a poor prognosis. Renal cell carcinoma has been reported in multiple case reports to be one of the most common distant lesions to spread to the paranasal sinuses. However, it is still rare and often unrecognized by physicians. We describe 3 cases of metastatic renal cell carcinoma to the sinonasal cavity which is the largest case series in the literature. This project will help educate physicians to include this in the differential and look for it on pathology.

The literature on external auditory canal cholesteatoma (EACC) remains scarce with only small case series published. A 2018 literature review identified 9 published case series with more than 10 patients with EACC, with the largest including 48 patients. Furthermore, our recent systematic review on the pathogenesis of primary EACC identified several theories and uncovered continued debate. The aim of this retrospective analysis is to elucidate EACC pathogenesis by examining all cases diagnosed at a large academic center in the United States, to compare findings in primary vs secondary EACC, and to develop the UF model for successful outcomes to treat EACC.