Multidisciplinary approaches to gliosarcoma: A case report and review of the literature.

A 58-year-old right-handed man presented to our tertiary care center with gliosarcoma (GS) infiltration through the dura, skull, and soft tissue. Patient had a previous history of right temporal GS, with four intracranial surgeries prior to presentation. A multidisciplinary approach was used to treat the lesion and perform reconstruction.

Phosphaturic Mesenchymal Tumors of the Sinonasal Area and Skull Base: Experience at a Single Institution.

OBJECTIVES: Phosphaturic mesenchymal tumor (PMT) is a rare, polymorphous neoplasm with a highly variable presentation and natural history and unpredictable clinical course. The primary objective was to describe our clinical experience with and management of 4 markedly different cases of sinonasal and skull base PMT. METHODS: A retrospective case series with chart review, and relevant literature review, was performed at a tertiary academic medical center between 1998 and 2020. Adult patients treated for PMTs of the sinonasal area and skull base were included. Our main outcome measures included postoperative laboratory findings and radiological evidence of disease remission. RESULTS: Four patients (2 Males, 2 Females; Mean Age: 63.5 years) with PMTs of the skull base have been managed at our institution since 1998. Patient presentations varied, ranging from severe phosphorus wasting and osteoporosis to symptoms secondary to mass effect, including nasal obstruction and rhinorrhea. All 4 patients were eventually found to have elevated levels of fibroblast growth factor 23. Tumors were located in the sinonasal area (right frontal sinus, right ethmoid sinus, and right nasal cavity, respectively) in 3 patients and in the lateral skull base (right jugular foramen) in 1 patient. All 4 patients underwent complete surgical resection of their tumors. PMT tissue pathology was confirmed in all cases. Gross total resection was achieved in all patients. There was no chemical or radiological evidence of disease recurrence in any patients at follow-up. CONCLUSIONS: The presentation of skull base PMT is variable, and it may mimic other mass pathologies of the head and neck. Complete surgical resection with negative margins is potentially curative.

Segmental mandibular reconstruction in patients with poor lower extremity perfusion, vessel-depleted necks and/or profound medical frailty.

PURPOSE OF REVIEW: Options for segmental mandibular reconstruction in patients poorly suited to undergo fibula free flap (FFF). RECENT FINDINGS: Although FFF is the current 'gold standard' for segmental mandibular reconstruction, other reconstructive options must be considered when FFF is contraindicated or disfavoured and/or patient frailty precludes a lengthy anaesthetic. In addition to various nonvascularized and soft tissue only reconstructions, excellent osseous free flap alternatives for functional segmental mandibular reconstruction may be employed. The subscapular system free flaps (SSSFF) may be ideal in frail and/or elderly patients, as SSSFF allows for early mobility and does not alter gait. In extensive and/or symphyseal defects, functional mandibular reconstruction in lieu of a free flap is extremely limited. Pedicled segmental mandibular reconstructions remain reasonable options, but limited contemporary literature highlights unpredictable bone graft perfusion and poor long-term functional outcomes. SUMMARY: There are several excellent free flap alternatives to FFF in segmental mandibular reconstruction, assuming adequate cervical recipient vessels are present. On the basis of the current literature, the optimal mandibular reconstruction for the medically frail, elderly and/or patients with extreme vessel-depleted necks is limited and debatable. In qualifying (i.e. limited, lateral) defects, soft tissue only reconstructions should be strongly considered when osseous free flaps are unavailable.

Delivery of Interleukin-4-Encoding Lentivirus Using Multiple-Channel Bridges Enhances Nerve Regeneration.

OBJECTIVES/HYPOTHESIS: Facial nerve injury is a source of major morbidity. This study investigated the neuroregenerative effects of inducing an anti-inflammatory environment when reconstructing a facial nerve defect with a multichannel bridge containing interleukin-4 (IL-4)-encoding lentivirus. STUDY DESIGN: Animal study. METHODS: Eighteen adult Sprague-Dawley rats were divided into three groups, all of which sustained a facial nerve gap defect. Group I had reconstruction performed via an IL-4 multichannel bridge, group II had a multichannel bridge with saline placed, and group III had no reconstruction. RESULTS: Quantitative histomorphometric data were assessed 10 weeks after injury. On post hoc analysis, the IL-4 bridge group demonstrated superior regeneration compared to bridge alone on fiber density (mean = 2,380 ± 297 vs. 1,680 ± 441 fibers/mm2 , P = .05) and latency time (mean = 2.9 ms ± 0.6 ms vs. 3.6 ms ± 0.3 ms, P < .001). There was significantly greater regeneration in the IL-4 bridge group versus unreconstructed defect for total fiber and density measurements (P ≤ .05). Comparison of facial motor-evoked distal latencies between the IL-4 bridge group versus bridge alone revealed significant electrophysiological improvement at week 8 (P = .02). CONCLUSIONS: Inflammation has been implicated in a variety of otolaryngologic disorders. This study demonstrates that placement of a multichannel bridge with lentivirus encoding IL-4 improves regenerative outcomes following facial nerve gap injury in rodents. This effect is likely mediated by promotion of an anti-inflammatory environment, and these findings may inform future therapeutic approaches to facial nerve injury. LEVEL OF EVIDENCE: NA Laryngoscope, 2020.

Sentinel Lymph Node Biopsy in Head and Neck Melanoma: Long-term Outcomes, Prognostic Value, Accuracy, and Safety.

OBJECTIVE: To evaluate the long-term outcomes of sentinel lymph node biopsy (SLNB) for head and neck cutaneous melanoma (HNCM). STUDY DESIGN: Retrospective cohort study. SETTING: Tertiary academic medical center. SUBJECTS AND METHODS: Longitudinal review of a 356-patient cohort with HNCM undergoing SLNB from 1997 to 2007. RESULTS: Descriptive characteristics included the following: age, 53.5 ± 19 years (mean ± SD); sex, 26.8% female; median follow-up, 4.9 years; and Breslow depth, 2.52 ± 1.87 mm. Overall, 75 (21.1%) patients had a positive SLNB. Among patients undergoing completion lymph node dissection following positive SLNB, 20 (27.4%) had at least 1 additional positive nonsentinel lymph node. Eighteen patients with local control and negative SLNB developed regional disease, indicating a false omission rate of 6.4%, including 10 recurrences in previously unsampled basins. Ten-year overall survival (OS) and melanoma-specific survival (MSS) were significantly greater in the negative sentinel lymph node (SLN) cohort (OS, 61% [95% CI, 0.549-0.677]; MSS, 81.9% [95% CI, 0.769-0.873]) than the positive SLN cohort (OS, 31% [95% CI, 0.162-0.677]; MSS, 60.3% [95% CI, 0.464-0.785]) and positive SLN/positive nonsentinel lymph node cohort (OS, 8.4% [95% CI, 0.015-0.474]; MSS, 9.6% [95% CI, 0.017-0.536]). OS was significantly associated with SLN positivity (hazard ratio [HR], 2.39; P < .01), immunosuppression (HR, 2.37; P < .01), angiolymphatic invasion (HR, 1.91; P < .01), and ulceration (HR, 1.86; P < .01). SLN positivity (HR, 3.13; P < .01), angiolymphatic invasion (HR, 3.19; P < .01), and number of mitoses (P = .0002) were significantly associated with MSS. Immunosuppression (HR, 3.01; P < .01) and SLN status (HR, 2.84; P < .01) were associated with recurrence-free survival, and immunosuppression was the only factor significantly associated with regional recurrence (HR, 6.59; P < .01). CONCLUSIONS: Long-term follow up indicates that SLNB showcases durable accuracy, safety, and prognostic importance for cutaneous HNCM.

Cranial nerve outcomes in regionally recurrent head & neck melanoma after sentinel lymph node biopsy.

OBJECTIVE: Characterize long-term cranial nerve (CN) outcomes following sentinel lymph node biopsy (SLNB) based management for head and neck cutaneous melanoma (HNCM). METHODS: Longitudinal review of HNCM patients undergoing SLNB from 1997-2007. RESULTS: Three hundred fifty-six patients were identified, with mean age 53.5 ± 19.0 years, mean Breslow depth 2.52 ± 1.87 mm, and 4.9 years median follow-up. One hundred five (29.4%) patients had SLNB mapping to the parotid basin. Eighteen patients had positive parotid SLNs and underwent immediate parotidectomy / immediate completion lymph node dissection (iCLND), with six possessing positive parotid non-sentinel lymph nodes (NSLNs). Fifty-two of 356 (14.6%) patients developed delayed regional recurrences, including 20 total intraparotid recurrences: five following false negative (FN) parotid SLNB, three following prior immediate superficial parotidectomy, two following iCLND without parotidectomy, and the remaining 12 parotid recurrences had negative extraparotid SLNBs. Parotid recurrences were multiple (4.9 mean recurrent nodes) and advanced (n = 4 extracapsular extension), and all required salvage dissection including parotidectomy. Immediate parotidectomy/iCLND led to no permanent CN injuries. Delayed regional HNCM macrometastasis precipitated 16 total permanent CN injuries in 13 patients: 10 CN VII, five CN XI, and one CN XII deficits. Fifty percent (n = 10) of parotid recurrences caused ≥1 permanent CN deficits. CONCLUSIONS: Regional HNCM macrometastases and salvage dissection confer marked CN injury risk, whereas early surgical intervention via SLNB ± iCLND ± immediate parotidectomy yielded no CN injuries. Further, superficial parotidectomy performed in parotid-mapping HNCM does not obviate delayed intraparotid recurrences, which increase risk of CN VII injury. Despite lack of a published disease-specific survival advantage in melanoma, early disease control in cervical and parotid basins is paramount to minimize CN complications. LEVEL OF EVIDENCE: 4 (retrospective case series) Laryngoscope, 130:1707-1714, 2020.

Machine Learning Diagnosis of Peritonsillar Abscess.

Peritonsillar abscess (PTA) is a difficult diagnosis to make clinically, with clinical examination of even otolaryngologists showing poor sensitivity and specificity. Machine learning is a form of artificial intelligence that "learns" from data to make predictions. We developed a machine learning classifier to predict the diagnosis of PTA based on patient symptoms. We retrospectively collected clinical data and symptomatology from 916 patients who underwent attempted needle aspiration for PTA. Machine learning classifiers were trained on a subset of the data to predict the presence or absence of purulence on attempted aspiration. The performance of the model was evaluated on a holdout set. The accuracy of the top-performing algorithm, the artificial neural network, was 72.3%. Artificial neural networks can use patient symptoms to exceed human ability to predict PTA in patients with clinical suspicion for PTA. Similar models can assist medical decision making for clinicians who have suspicion of PTA.

Effect of Motor versus Sensory Nerve Autografts on Regeneration and Functional Outcomes of Rat Facial Nerve Reconstruction.

Cranial nerve injury is disabling for patients, and facial nerve injury is particularly debilitating due to combined functional impairment and disfigurement. The most widely accepted approaches for reconstructing nerve gap injuries involve using sensory nerve grafts to bridge the nerve defect. Prior work on preferential motor reinnervation suggests, however, that motor pathways may preferentially support motoneuron regeneration after nerve injury. The effect of motor versus sensory nerve grafting after facial nerve injury has not been previously investigated. Insights into outcomes of motor versus sensory grafting may improve understanding and clinical treatment of facial nerve paralysis, mitigating facial asymmetry, aberrant reinnervation, and synkinesis. This study examined motor versus sensory grafting of the facial nerve to investigate effect of pathway on regeneration across a 5-mm rodent facial nerve defect. We enrolled 18 rats in 3 cohorts (motor, sensory, and defect) and recorded outcome measures including fiber count/nerve density, muscle endplate reinnervation, compound muscle action potential, and functional whisker twitch analysis. Outcomes were similar for motor versus sensory groups, suggesting similar ability of sensory and motor grafts to support regeneration in a clinically relevant model of facial nerve injury.

Comparison of Myelin-Associated Glycoprotein With Vincristine for Facial Nerve Inhibition After Bilateral Axotomy in a Transgenic Thy1-Gfp Rat Model.

IMPORTANCE: Aberrant synkinetic movement after facial nerve injury can lead to prominent facial asymmetry and resultant psychological distress. The current practices of neuroinhibition to promote greater facial symmetry are often temporary in nature and require repeated procedures. OBJECTIVE: To determine whether myelin-associated glycoprotein (MAG), a specific neuroinhibitor, can prevent neuroregeneration with efficacy comparable with that of vincristine, a well-established neurotoxin. DESIGN, SETTING, AND PARTICIPANTS: Rats transgenic for Thy-1 cell surface antigen-green fluorescent protein (Thy1-Gfp) were randomized into 3 groups. Each rat received bilateral crush axotomy injuries to the buccal and marginal mandibular branches of the facial nerves. The animals received intraneural injection of saline, MAG, or vincristine. MAIN OUTCOMES AND MEASURES: The animals were imaged via fluorescent microscopy at weeks 1, 3, 4, and 5 after surgery. Quantitative fluorescent data were generated as mean intensities of nerve segments proximal and distal to the axotomy site. Electrophysiological analysis, via measurement of compound muscle action potentials, was performed at weeks 0, 3, 4, and 5 after surgery. RESULTS: A total of 12 rats were included in the study. Administration of MAG significantly reduced fluorescent intensity of the distal nerve in comparison with the control group at week 3 (mean [SD], MAG group: 94 [11] intensity units vs control group: 130 [11] intensity units; P < .001), week 4 (MAG group: 81 [19] intensity units vs control group: 103 [9] intensity units; P = .004), and week 5 (MAG group: 76 [10] intensity units vs control group: 94 [10] intensity units; P < .001). In addition, rats treated with MAG had greater fluorescent intensity than those treated with vincristine at week 3 (mean [SD], MAG group: 94 [11] intensity units vs vincristine group: 76 [6] intensity units; P = .03), although there was no significant difference for weeks 4 and 5. At week 5, both MAG and vincristine demonstrated lower distal nerve to proximal nerve intensity ratios than the control group (control group, 0.94; vs MAG group, 0.82; P = .01; vs vincristine group; 0.77; P < .001). There was no significant difference in amplitude between the experimental groups at week 5 of electrophysiological testing. CONCLUSIONS AND RELEVANCE: Lower facial asymmetry and synkinesis are common persistent concerns to patients after facial nerve injury. Using the Thy1-Gfp rat, this study demonstrates effective inhibition of neuroregeneration via intraneural application of MAG in a crush axotomy model, comparable with results with vincristine. By potentially avoiding systemic toxic effects of vincristine, MAG demonstrates potential as an inhibitor of neural regeneration for patients with synkinesis. LEVEL OF EVIDENCE: NA.

The White Lesion, Hyperkeratosis, and Dysplasia.

Laryngeal mucosal precursor lesions represent a challenging clinical entity. Updated classification systems allow for grade-based categorization. Multiple management options exist, with treatment decisions made jointly by physician and patient and focused on both appropriate lesion treatment and preservation of laryngeal structure and function. Traditional methods include cold steel and CO2 laser excision, with newer modalities using angiolytic lasers for lesion ablation. Both operating room-based and office-based treatment options exist, and there are advantages and disadvantages to each approach. Research is ongoing to advance the understanding of lesion biology, and to optimize prevention and treatment.

Implication of Fusobacterium necrophorum in recurrence of peritonsillar abscess.

OBJECTIVE: Peritonsillar abscess (PTA) is a common infectious complication of pharyngeal infection managed by otolaryngologists and emergency room physicians. Streptococcus and Fusobacterium (e.g., Fusobacterium necrophorum, FN) species are commonly isolated pathogens. The aim of this study was to determine the implication of culture results on abscess recurrence following drainage. METHODS: Single-institution retrospective review of patients treated at the University of Michigan between 2000 and 2017. Demographic and clinical outcome data were analyzed, including treatment details, culture data, and recurrence. RESULTS: One hundred fifty-six of the 990 patients in our study developed recurrence of their abscess (16%). The age ranges most susceptible to recurrence included adolescent (22.9%) and young adult groups (17.1%). Recurrent patients were more likely to have experienced acute progression of symptoms (79% vs. 71%, P = 0.03), trismus (67% vs. 55%, P = 0.006), voice changes (65% vs. 57%, P = 0.04), and dysphagia (72% vs. 61%, P = 0.01) compared to nonrecurrent patients. They were also more likely to have clinical lymphadenopathy noted on initial examination (67% vs. 56%, P = 0.009). Culture data was sent for 852 patients (86%). The presence of FN was significantly more prevalent in the recurrent group (P < 0.0001). CONCLUSION: There is a high observed prevalence of FN species within PTA aspirates in the recurrent PTA population. PTA aspirate should be sent for anaerobic growth to screen for Fusobacterium species. In addition, follow-up and lower threshold for subsequent tonsillectomy should be considered in this at-risk group. LEVEL OF EVIDENCE: 3 Laryngoscope, 129:1567-1571, 2019.

Predictors of intratonsillar versus peritonsillar abscess: A case-control series.

OBJECTIVES/HYPOTHESIS: An uncommon phenomenon in relation to the peritonsillar abscess (PTA) is the intratonsillar abscess (ITA) or formation of an abscess within tonsillar parenchyma. This study sought to characterize our experience with diagnosis and management of ITAs in the context of the PTA patient population. STUDY DESIGN: Case-control series. METHODS: This is a single-institution retrospective review of patients treated at the University of Michigan between 2000 and 2017. RESULTS: Six hundred fifty-five adult patients were identified. The incidence of ITA within the PTA population was 7% (n = 43). Patients with ITA had lower mean white blood cell count (P = .03), lower proportion of trismus (P < .0001), otalgia (P = .007), vocal changes (P < .0001), and fewer incidences of acute progression of symptoms (P = .0007). On multivariable analysis, ITA patients were noted to be older, present with a longer duration of symptoms, and have greater incidence of neck pain and lymphadenopathy. Drainage was attempted in fewer ITA patients and was rarely successful (15%) in comparison to successful drainage for PTA patients (69%) (P < .0001). CONCLUSIONS: Symptomatology differs for ITA, as fewer present with the classic PTA symptoms of otalgia, trismus, and voice alterations. The lack of classic symptoms likely leads to delayed presentation. A greater number of ITA patients presented with neck pain and lymphadenopathy. In the ITA population, aspiration attempts were more infrequent and less successful in yielding purulence. Given infrequent yield of pus and low overall recurrence rate, the diagnosing clinician should consider medical management in this distinct patient population. LEVEL OF EVIDENCE: 4 Laryngoscope, 129:1354-1359, 2019.