Faculty Bibliography

Aspirin-exacerbated respiratory disease (AERD) is characterized by abnormal arachidonic acid metabolism leading to chronic rhinosinusitis with nasal polyposis (CRSwNP), asthma, and upper and/or lower respiratory symptoms after ingestion of cyclooxygenase-1 inhibiting nonsteroidal antiinflammatory drugs. Diagnosis is clinical and may involve an aspirin challenge. Inflammatory biomarkers may be useful for diagnosis and treatment monitoring. Conventional medical management for asthma and CRSwNP is often inadequate. Endoscopic sinus surgery followed by continued medical management with or without aspirin desensitization frequently improves symptoms and objective disease measures. Biological agents targeting eosinophilic inflammation are promising alternatives to conventional management.

Hands-on dissections using cadaveric tissues for neuroanatomical education are not easily available in many educational institutions due to financial, safety, and ethical factors. Supplementary pedagogical tools, for instance, 3D models of anatomical specimens acquired with photogrammetry are an efficient alternative to democratize the 3D anatomical data. The aim of this study was to describe a technical guideline for acquiring realistic 3D anatomic models with photogrammetry and to improve the teaching and learning process in neuroanatomy. Seven specimens with different sizes, cadaveric tissues, and textures were used to demonstrate the step-by-step instructions for specimen preparation, photogrammetry setup, post-processing, and display of the 3D model. The photogrammetry scanning consists of three cameras arranged vertically facing the specimen to be scanned. In order to optimize the scanning process and the acquisition of optimal images, high-quality 3D models require complex and challenging adjustments in the positioning of the specimens within the scanner, as well as adjustments of the turntable, custom specimen holders, cameras, lighting, computer hardware, and its software. MeshLab® software was used for editing the 3D model before exporting it to MedReality® (Thyng, Chicago, IL) and SketchFab® (Epic, Cary, NC) platforms. Both allow manipulation of the models using various angles and magnifications and are easily accessed using mobile, immersive, and personal computer devices free of charge for viewers. Photogrammetry scans offer a 360° view of the 3D models ubiquitously accessible on any device independent of operating system and should be considered as a tool to optimize and democratize the teaching of neuroanatomy.

BACKGROUND:The lingual process of the sphenoid bone (LP) and the petrolingual ligament (PLL) surround laterally the internal carotid artery within the middle cranial fossa (MCF). OBJECTIVE:To study the LP and the PLL and anatomical variations considering their relationships with different structures and landmarks within the MCF, especially oriented toward the endoscopic endonasal approaches. METHODS:Seventy-two sides of dry skulls and 20 sides of embalmed specimens were studied. The measurements of the LP and the PLL were obtained, considering important landmarks in the MCF. RESULTS:The LP had a mean length and height of 5 mm and 3 mm, respectively. Its distance from the foramen lacerum was 6 mm, from the foramen ovale 10 mm, foramen rotundum 15 mm, and petrous apex 9 mm. In 44 sides (61.11%), the LP partially closed the lateral aspect of the carotid sulcus; in 17 sides (23.61%), it was found as a near-ring; and in 11 sides (15.2%), it was considered rudimentary. Considering the PLL, its length and height were, respectively, 9 mm, and 4 mm. CONCLUSION:The LP and PLL separate the carotid artery at the inferior aspect of Meckel's cave and constitute important landmarks for endoscopic endonasal approaches to Meckel's cave and MCF, and their identification and removal is essential for internal carotid artery mobilization in this area.

OBJECTIVE:Esthesioneuroblastoma (ENB) is a rare malignant neoplasm arising from the olfactory epithelium of the cribriform plate. The goal of this study was to update our oncologic outcomes for this disease and explore prognostic factors associated with survival. MATERIALS AND METHODS:We performed a retrospective analysis of patients with ENB treated at a single tertiary care institution from January 1, 1960, to January 1, 2020. Univariate and multivariate analysis was performed. Overall survival (OS), progression-free survival (PFS), and distant metastasis-free survival (DMFS) were reported. RESULTS:Among 143 included patients, the 5-year OS was 82.3% and the 5-year PFS was 51.6%; 5-year OS and PFS have improved in the modern era (2005-present). Delayed regional nodal metastasis was the most common site of recurrence in 22% of patients (median, 57 months). On univariate analysis, modified Kadish staging (mKadish) had a negative effect on OS, PFS, and DMFS (p < 0.05). Higher Hyams grade had a negative effect on PFS and DMFS (p < 0.05). Positive margin status had a negative effect on PFS (p < 0.05). Orbital invasion demonstrated worsening OS (hazard ratio, 3.1; p < 0.05). On multivariable analysis, high Hyams grade (3 or 4), high mKadish stage (C+D), and increasing age were independent negative prognostic factors for OS (p < 0.05). High Hyams grade (3+4), high mKadish stage (C+D), age, and positive margin status were independent negative prognostic factors for PFS (p < 0.05). High Hyams grade (3+4) was an independent negative prognostic factor for DMFS (p < 0.05). CONCLUSIONS:Patients with low Hyams grade and mKadish stage have favorable 5-year OS, PFS, and DMFS.

OBJECTIVE:The aim of this study is to verify if the length of the nasoseptal flap is sufficient to cover the tuberculum sellae and planum sphenoidale of sphenoidal sinuses with varied degrees of pneumatization. METHODS:Retrospective study of paranasal sinus computed tomography comparing the potential length of the nasoseptal flap and the length of the nasoseptal flap required for reconstruction of transtuberculum and transplanum approaches in conchal, presellar, sellar, incomplete postsellar, and complete postsellar sphenoidal sinuses. RESULTS:The length of the nasoseptal flap required for reconstruction of transtuberculum and transplanum approaches was directly related to the degree of pneumatization of the sphenoidal sinus. The nasoseptal flap length was adequate to cover the cranial base after transtuberculum approaches of all cases from the conchal, presellar, and sellar groups and the majority of cases from postsellar pneumatization. For transplanum approaches, the nasosseptal flap was sufficient to reconstruct defects in most cases from conchal, pre-sellar, and sellar type sinuses and in 54,9% and 19,2% in incomplete and complete postsellar, respectively. CONCLUSIONS:In well pneumatized sphenoidal sinus, the nasoseptal flap may not be sufficient to cover the cranial base after transtuberculum and transplanum approaches.

PURPOSE:Traditional endoscopic endonasal approaches to the cavernous sinus (CS) open the anterior CS wall just medial to the internal carotid artery (ICA), posing risk of vascular injury. This work describes a potentially safer midline sellar entry point for accessing the CS utilizing its connection with the inferior intercavernous sinus (IICS) when anatomically present. METHODS:The technique for the midline intercavernous dural access is described and depicted with cadaveric dissections and a clinical case. RESULTS:An endoscopic endonasal approach exposed the periosteal dural layer of anterior sella and CS. The IICS was opened sharply in midline through its periosteal layer. The feather knife was inserted and advanced laterally within the IICS toward the anterior CS wall, thereby gradually incising the periosteal layer of the IICS. The knife was turned superiorly then inferiorly in a vertical direction to open the anterior CS wall. This provided excellent access to the CS compartments, maintained the meningeal layer of the IICS and the medial CS wall, and avoided an initial dural incision immediately adjacent to the ICA. CONCLUSION:The midline intercavernous dural access to the CS assisted by a 90° dissector-blade is an effective modification to previously described techniques, with potentially lower risk to the ICA.

BACKGROUND:Trigeminal schwannomas (TSs) with solitary extracranial location are rare, and surgical excision is challenging. In recent years, the endoscopic endonasal transmaxillary transpterygoid approach (EETPA) has been advocated as an effective strategy for TSs in the infratemporal fossa (ITF). METHOD:We describe the steps of the EETPA combined with the sublabial transmaxillary approach for the surgical excision of a giant mandibular schwannoma of the ITF. Indications, advantages, and approach-specific complications are also discussed. The main surgical steps are shown in an operative video. CONCLUSION:A combined EETPA and sublabial transmaxillary approach represents a safe and effective option for the surgical excision of extracranial TSs.