Peris Celda, Maria

Abstract Introduction The development of endoscopic techniques has made endoscopic endonasal approaches (EEAs) to the anterior cranial fossa (ACF) increasingly popular. Still, the steps and nuances involved in the approach may be difficult to understand for trainees. Thus, we aim to didactically describe the EEAs to the ACF in an anatomically based, step-by-step manner with supplementary clinical cases. Methods Six cadaveric head specimens were dissected. Endoscopic endonasal Draf I, IIA, IIB, and III frontal sinusotomies, endoscopic endonasal superior ethmoidectomy, and endoscopic endonasal transcribriform and transplanum approaches were modularly performed. The specimens were photodocumented with endoscopic techniques. Results Draf I frontal sinusotomy started with the complete removal of the anteromedial portion of the agger nasi cell, exposing the medial orbital wall, cranial base, and anterior cribriform plate. Draf II frontal sinusotomy proceeded with the removal of the floor of the frontal sinus between the lamina papyracea and the middle turbinate (IIa), and the nasal septum (IIb) until the first olfactory filaments were exposed. Draf III proceeded by creating a superior septal window just below the floor of the frontal sinus. The bone of the ACF bounded by the limbus sphenoidale posteriorly, frontal sinus anteriorly, and the medial orbital walls bilaterally was removed; the cribriform plate was removed; and the crista galli was dissected free from the dural leaflets of the falx cerebri and removed. Conclusion We provide a step-by-step dissection describing basic surgical steps and anatomy of the EEAs to the ACF to facilitate the learning process for skull base surgery trainees.

BACKGROUND AND OBJECTIVES: Vestibular schwannomas (VS) are often phenotypically benign lesions that may be technically challenging to resect because of involvement of neurovascular structures. The anterior inferior cerebellar artery (AICA) is commonly identified near VS, with variable position in relation to the tumor; however, little published literature describes anatomic and pathologic variants of AICA observed during VS resection. METHODS: A prospectively maintained cohort of surgically managed VS with available operative reports and clinical/radiographic follow-up was queried and reviewed for noted aberrations. RESULTS: We identified 66 cases with noted AICA abnormalities among 880 reviewer cases, including 20 loops extending into the internal auditory canal (2.3%), 18 arteries embedded in dura (2.0%), 15 AICA branches directly within VS (1.7%), 8 main trunk arteries coursing between cranial nerves 7 and 8 (0.9%), 3 arteries embedded in temporal bone (0.2%), 1 aneurysm (0.1%), and 1 artery bifurcating cranial nerve 6 (0.1%). The median age of AICA-variant patients was 55 years (range 19-74), and 29 were female (45%). Compared with the other AICA variants, tumors embedded with AICA tended to be larger lesions on maximal axial diameter (2.9 vs 1.6 cm; P = .006), they more commonly underwent less than total resection (73% vs 28%; P = .0001), and they had higher rates postoperative House-Brackmann scores >2 (47% vs 20%; P = .005). Two patients had radiographic and symptomatic postoperative cerebral ischemia or hemorrhage—1 from a bone-encased AICA and 1 from a dural embedded variant. CONCLUSION: Anatomic variants of AICA occur in approximately 7% of VS operations. Most aberrations do not affect surgical or clinical outcomes, and the rate of major vascular injury was low. However, certain types variably add operative time and in the case of AICA encasement in the tumor, likely indicate a more aggressive tumor phenotype with lower rates of gross total resection and high incidences of facial nerve weakness.

ImportanceCurrent olfactory neuroblastoma (ONB) staging systems inadequately delineate locally advanced tumors, do not incorporate tumor grade, and poorly estimate survival and recurrence.ObjectiveThe primary aims of this study were to (1) examine the clinical covariates associated with survival and recurrence of ONB in a modern-era multicenter cohort and (2) incorporate Hyams tumor grade into existing staging systems to assess its ability to estimate survival and recurrence.Design, Setting, and ParticipantsThis retrospective, multicenter, case-control study included patients with ONB who underwent treatment between January 1, 2005, and December 31, 2021, at 9 North American academic medical centers.InterventionStandard-of-care ONB treatment.Main Outcome and MeasuresThe main outcomes were overall survival (OS), disease-free survival (DFS), and disease-specific survival (DSS) as C statistics for model prediction.ResultsA total of 256 patients with ONB (mean [SD] age, 52.0 [15.6] years; 115 female [44.9%]; 141 male [55.1%]) were included. The 5-year rate for OS was 83.5% (95% CI, 78.3%-89.1%); for DFS, 70.8% (95% CI, 64.3%-78.0%); and for DSS, 94.1% (95% CI, 90.5%-97.8%). On multivariable analysis, age, American Joint Committee on Cancer (AJCC) stage, involvement of bilateral maxillary sinuses, and positive margins were associated with OS. Only AJCC stage was associated with DFS. Only N stage was associated with DSS. When assessing the ability of staging systems to estimate OS, the best-performing model was the novel modification of the Dulguerov system (C statistic, 0.66; 95% CI, 0.59-0.76), and the Kadish system performed most poorly (C statistic, 0.57; 95% CI, 0.50-0.63). Regarding estimation of DFS, the modified Kadish system performed most poorly (C statistic, 0.55; 95% CI, 0.51-0.66), while the novel modification of the AJCC system performed the best (C statistic, 0.70; 95% CI, 0.66-0.80). Regarding estimation of DSS, the modified Kadish system was the best-performing model (C statistic, 0.79; 95% CI, 0.70-0.94), and the unmodified Kadish performed the worst (C statistic, 0.56; 95% CI, 0.51-0.68). The ability for novel ONB staging systems to estimate disease progression across stages was also assessed. In the novel Kadish staging system, patients with stage VI disease were approximately 7 times as likely to experience disease progression as patients with stage I disease (hazard ratio [HR], 6.84; 95% CI, 1.60-29.20). Results were similar for the novel modified Kadish system (HR, 8.99; 95% CI, 1.62-49.85) and the novel Dulguerov system (HR, 6.86; 95% CI, 2.74-17.18).Conclusions and RelevanceThe study findings indicate that 5-year OS for ONB is favorable and that incorporation of Hyams grade into traditional ONB staging systems is associated with improved estimation of disease progression.

Abstract Background Hemangioblastomas pose an inherent surgical risk due to the potential for high intraoperative blood loss, especially in larger tumors. One approach to minimize this risk is to use preoperative embolization. Herein, we present our institutional experience treating large and giant cerebellar hemangioblastomas. Methods We performed a retrospective chart review of 19 patients with cerebellar hemangioblastomas that had a maximal diameter of >3 cm. We performed a literature review and included individual patient-level data that met our >3 cm diameter cerebellar hemangioblastoma inclusion criteria. Results Our cohort consisted of 19 patients that received a total of 20 resections for their cerebellar hemangioblastomas. Preoperative embolization was utilized in eight cases (38.1%). One patient experienced transient neurological complications after embolization (12.5%). Tumors of patients in the embolization group had larger median total, solid, and cystic volumes and were more likely to involve the cerebellopontine angle than those in the non-embolized group. Compared with non-embolized patients, embolized patients had less decrease in their hemoglobin, lower volumes of estimated blood loss, reduced rates of postoperative complications and permanent deficits, and greater instances of neurological improvement. The larger cohort (obtained from the combining our cohort with patients identified during a literature review) consisted of 99 patients with 39 receiving preoperative embolization. Conclusion It is important to examine individual patient characteristics when determining eligibility for preoperative embolization. However, improvements in endovascular techniques have made preoperative embolization a safe and effective procedure with minimal risks that can be performed in many patients.

AbstractObjectiveEsthesioneuroblastoma (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 methodsWe 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.ResultsAmong 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).ConclusionsPatients with low Hyams grade and mKadish stage have favorable 5‐year OS, PFS, and DMFS.