ABSTRACTBackgroundOlfactory neuroblastoma (ONB) is a rare sinonasal malignancy primarily treated with surgery. For tumors arising from the olfactory area, traditional treatment involves transcribriform resection of the anterior cranial fossa. Surgery can be performed with unilateral or bilateral resection depending on extent of involvement; however, there are currently no studies comparing outcomes between the two.MethodsProspective and retrospective data on primary ONB patients were collected from a multicenter registry involving eight academic sites. Propensity score matching (PSM) was used to create patient cohorts with similar baseline characteristics. Cox proportional hazards and Kaplan Meier analyses assessed overall survival (OS). Logistic regression assessed associations between extent of resection (unilateral versus bilateral) and tumor recurrence or postoperative cerebrospinal fluid (CSF) leak.ResultsA total of 187 ONB patients (47.6% female) with an average age of 53.6 ± 15.1 years were analyzed. Most tumors were unilateral (81.3%) and predominantly Kadish C (58.3%) or Hyams II (55.8%). Overall, 56.7% of patients underwent bilateral resection. Fifty‐four patients experienced tumor recurrence and nine had postoperative CSF leaks. Following PSM (n = 45/group), extent of resection was not associated with mortality (hazard ratio [HR] 1.73; p = 0.407) or OS (p = 0.400). There was no association between extent of resection and recurrence (odds ratio [OR] 0.90; p = 0.814) or postoperative CSF leak (OR 1.54; p = 0.647).ConclusionsFor ONB tumors where unilateral resection may be feasible and oncologically sound, the decision for unilateral versus bilateral resection showed no significant effect on survival, recurrence, or postoperative CSF leak. Oncologic outcomes may be comparable when resection is tailored to individual patient and tumor characteristics.
Outcomes of Immunotherapy Treatment in Sinonasal Mucosal Melanoma
Background Sinonasal mucosal melanoma has poor survival despite multimodality treatment. While the impact of immunotherapy (IT) on metastatic cutaneous melanoma is well-defined, there are relatively little data on sinonasal mucosal melanoma. Objective We sought to define immunotherapy outcomes in patients with sinonasal mucosal melanoma. Methods A retrospective cohort study evaluated patients treated with IT during their overall treatment strategy for SNMM. Patient demographics, treatment, and survival outcomes were recorded. Results 52 patients had IT treatment for SNMM from 2000 to 2022, with an average age of 69.1 ± 11.9 years. The most common treatment was surgery with radiation and IT ( n = 26, 50%). Most regimens consisted of a combination of Nivolumab and Ipilimumab ( n = 17, 32.7%) or pembrolizumab ( n = 14, 26.9%). 44.2% of patients experienced reported complications. Overall survival at 1-, 2-, and 5 years was 86.9%, 74.1%, and 39.1%, respectively. Conclusion Approximately half of patients will have a local response following immunotherapy, but it is rare to have improvement at metastatic locations. Further research within our group will assess optimal timing and markers that are predictive of response.
Correlation of the Sinonasal Outcome Test‐22 With the University of Washington Quality of Life in Assessing Quality of Life in Sinonasal Malignancy Utilizing a Multicenter Prospective Observational Cohort Registry
OBJECTIVE The floor of the third ventricle and the interpeduncular and prepontine regions represent challenging surgical targets. The expanded endoscopic endonasal approach (EEA) with pituitary gland (PG) transposition has been proposed to provide direct access to these anatomical regions. Through the years, different endoscopic PG transposition techniques have been studied and presented. The goal of this study was to compare the techniques, relevant anatomy, and surgical exposure of extradural, intradural, and interdural PG transposition techniques. METHODS Six formalin-fixed, latex-injected cadaveric head specimens were used to perform the EEA with extradural, unilateral interdural, and unilateral intradural PG transpositions. The interpeduncular and prepontine regions and the neurovascular structures located within these cisterns were carefully exposed and analyzed. The maximal cranial, caudal, and lateral accessible points within the surgical field were identified for each approach. Consequently, the relative craniocaudal and horizontal surgical axes were measured to quantify the extent of accessibility of each approach. RESULTS The extradural PG transposition technique provided the largest horizontal extensions and bilateral access to structures within the interpeduncular and prepontine regions; the mean horizontal axis was 17.9 (range 13.9–20.4) mm. The unilateral interdural PG transposition provided wider vertical exposure, with a mean craniocaudal axis of 16.2 (range 13.0–20.9) mm. In this approach, the surgical field was extended cranially above the ipsilateral mammillary body (MB). The unilateral intradural PG transposition provided a similar surgical exposure to the interdural approach, with a mean craniocaudal axis of 14.7 (range 12.9–15.8) mm. The approach required significant manipulation of the PG after opening both periosteal and meningeal dura layers. CONCLUSIONS The extradural PG transposition is indicated for lesions of the upper clivus region that extend bilaterally and do not have a cranial extension beyond the MBs. The inter- and intradural PG transpositions are beneficial for unilateral lesions that extend cranially to the MBs. Both techniques require coagulation of the ipsilateral inferior hypophyseal artery. The intradural technique requires more manipulation of the PG, while the interdural technique requires opening and access to the cavernous sinus. If needed, the intra- and interdural techniques can also be performed bilaterally.
Mobilization of the Maxillary Lateral Buttress to Connect the Infratemporal Fossa and Buccal Space in Sublabial Approaches
AbstractObjectiveNeck metastases are a poor prognostic factor in olfactory neuroblastoma (ONB). Pathologic dural invasion (pathDI) may increase the risk of neck metastases due to invasion of dural lymphatics. We aim to evaluate the prognostic value of pathDI in predicting rates of neck metastases and recurrence using a large, multicenter database of ONB patients.Data sourcesRetrospective review of a prospective, multicenter database of electronic health records of all patients who presented with ONB between 2005 and 2021 at nine tertiary academic care centers within North America.Review methodsClinicopathologic features including modified Kadish staging systems, margin status, treatment modalities, Hyams grading, follow‐up time, and survival.ResultsOf 258 ONB patients, 189 patients met the inclusion criteria. The 10‐year neck recurrence‐free survival (neck‐RFS) rates were 85.7% (75.6‒97.3) and 61.8% (47.9‒79.8) for patients without and with pathDI, respectively (p = 0.018). Time‐to‐event multivariable regression analysis found pathDI to have an odds ratios of 9.7 (95% confidence interval [CI] 1.2–80.4, p = 0.04) for neck‐RFS and 9.5 for RFS at any site (95% CI 1.1–83.3, p = 0.04).ConclusionIn multivariable analysis, the presence of pathDI appears to be the strongest predictor of neck recurrence and recurrence at any site. Future studies exploring the benefit of elective neck dissection or radiation for patients with pathDI may impact disease management.
Origin and Course Cavernous Internal Carotid Artery Branches from the Endoscopic Endonasal Perspective: Cadaveric Study and Analysis Clinical Implications
BACKGROUND AND OBJECTIVE: Endoscopic endonasal approaches to treat cavernous sinus lesions require detailed knowledge of the origin, course, and anatomic variations of the branches of the cavernous internal carotid artery (cICA) because inadvertent avulsion can cause intraoperative ICA injury. We aim to study the origin and course of the branches of the cICA from an endoscopic endonasal perspective and relate these branches to surgically relevant anatomic references. METHODS: Sixty sides of 30 formalin-fixed specimens were dissected to identify the origin and course of cICA branches, including the inferolateral trunk (ILT), the meningohypophyseal trunk (MHT), anterior and inferior McConnell's capsular arteries (MCAs), and the superolateral trunk (SLT). RESULTS: The ILT and MHT were bilaterally in all specimens, whereas the anterior and inferior MCAs were identified in 28% and 25% of dissected sides, respectively. The SLT was only found in 3% of sides dissected. The MHT was the most proximal branch of the cICA, and its origin was an average of 8.9 mm anterior to the foramen lacerum and 3.8 mm superior to the sellar floor. The ILT was the second most proximal branch of the cICA, which originated 6.4 mm from the MHT on average. The anterior and inferior MCAs were present in 28% and 25% of specimens, respectively. The SLT, when present, was the second most proximal branch of the cICA, which originated at a mean height of 2.7 mm from the sellar floor. Overall, complete ILT and MHT were identified in 68% and 77% of cases, respectively. CONCLUSION: The MHT and ILT are constant branches of the cICA, with the MHT originating from the medial cICA posterior bend 4 mm superior to the sellar floor and 9 mm anterior to the foramen lacerum, whereas the ILT arises from the lateral horizontal cICA, 2.3 mm superior to the sellar floor and 6 mm anterior to the MHT.
A Case of Nasoseptal Flap Reconstruction for Refractory Medial Canthal Fistula
Sino-orbital cutaneous fistulas (SOCFs) are a rare and challenging complication from conditions including granulomatosis with polyangiitis. SOCFs are difficult to manage due to poor vascular supply, compromised tissue, and systemic immunocompromise, which lead to a high rate of recurrence. Given the overall rarity of SOCFs, optimal surgical repair remains controversial, with options ranging from conservative management, onlay grafts, and vascularized flaps. This case report describes a novel one-step approach to SOCF closure using a composite chondral mucosal nasoseptal flap in a patient with a large left medial canthal SOCF that had recurred despite 2 prior attempts at closure including a vascularized paramedian forehead flap. Nasoseptal flaps may provide vascularized mucosal tissue to allow for greater success in closure over traditional, external flaps, and skin grafts.
Pilot Program in Surgical Anatomy Education for Complex Cranial and Skull Base Procedures: Curriculum Overview and Initial 2-Year Experience at Mayo Clinic
Abstract Background Cadaveric dissection remains a preferred and irreplaceable learning modality among neurosurgery residents. We aimed to develop and describe a tiered, quantifiable, and practical curriculum for cranial neurosurgical anatomy education. We report the structure and evaluation of our 2-year pilot study to serve as a suggested guide for other neurosurgery programs. Methods Our Complex Cranial Dissection Program is tailored to the needs of junior-level neurosurgery residents based on their postgraduation years 1 to 4. Dissections are performed in a sequential manner, each of which emphasize a particular set of manual skills and neuroanatomical knowledge. Dissections are scored on a scale of 10 points. The grading was based on specific landmarks and anatomical structures, which need to be exposed, explored, and preserved. Results Out of 16 residents, 14 individuals (87.5%) attended the dissections in the first iteration of the program and 16 individuals (100%) attended the dissections in the second iteration. A total of 17 dissections were performed across all years. In survey feedback about the program, 100% (Year 1) and 94% (Year 2) of residents considered the assigned dissections to be appropriate for their respective training levels. Further, 100% (Year 1) and 94% (Year 2) of residents endorsed that the dissections were important and helpful for their practice prior to similar operating room experiences. Conclusion The development and implementation of structured dissection programs within residency training, along with dedicated staff, and objective feedback serve a crucial role in neurosurgical education to further develop and enhance surgical skills in the operative setting.
The Coexistence of Carotico-Clinoid Foramen and Interclinoidal Osseous Bridge: An Anatomo-Radiological Study With Surgical Implications
BACKGROUND AND OBJECTIVES: The coexistence of complete carotico-clinoid bridge (CCB), an ossification between the anterior (ACP) and the middle clinoid (MCP), and an interclinoidal osseous bridge (ICB), between the ACP and the posterior clinoid (PCP), represents an uncommonly reported anatomic variant. If not adequately recognized, osseous bridges may complicate open or endoscopic surgery, along with the pneumatization of the ACP, especially when performing anterior or middle clinoidectomies. METHODS: According to Preferred Reporting Items for Systematic Reviews and Meta-Analyses for Scoping Reviews guidelines, a systematic scoping review was conducted up to June 5, 2023. PubMed, Scopus, Web of Science databases, and additional citations were searched. Two hundred high-resolution noncontrast computed tomography (CT) scans (400 sides) and 41 dry skulls (82 sides) were analyzed to identify the different morphology of sellar bridges, focusing on the coexistence of complete CCF and ICB. Two embalmed latex-injected heads with coexisting CCF and ICB were dissected step-by-step to show the anatomic relationship with the surrounding structures from an endoscopic and microscopic perspective. RESULTS: A total of 19 articles were included. The review identified a complete CCF and ICB rate ranging from 4.92% to 6.3%. The analysis of 200 CT scans revealed a rate of coexistence in 4% of the cases, all encountered in White women. Two different types of interclinoid bridges were identified based on the degree of bone mineralization. Both endoscopic and macroscopic step-by-step dissections highlighted variability in morphology and consistency of the sellar bridges and the close relationship with the cavernous sinus neurovascular structures. CONCLUSION: The coexistence of CCF and ICB is an anatomic variation found in 4% of cases. Preoperative knowledge of the degree of mineralization and its relationship with surrounding structures is essential to performing safe surgery and minimizing cranial nerve and vascular injuries. Preoperative high-resolution CT scans can adequately identify these anatomic variations.