Three contrasts in 3 min: Rapid, high-resolution, and bone-selective UTE MRI for craniofacial imaging with automated deep-learning skull segmentation.

PURPOSE: Ultrashort echo time (UTE) MRI can be a radiation-free alternative to CT for craniofacial imaging of pediatric patients. However, unlike CT, bone-specific MR imaging is limited by long scan times, relatively low spatial resolution, and a time-consuming bone segmentation workflow. METHODS: A rapid, high-resolution UTE technique for brain and skull imaging in conjunction with an automatic segmentation pipeline was developed. A dual-RF, dual-echo UTE sequence was optimized for rapid scan time (3 min) and smaller voxel size (0.65 mm3). A weighted least-squares conjugate gradient method for computing the bone-selective image improves bone specificity while retaining bone sensitivity. Additionally, a deep-learning U-Net model was trained to automatically segment the skull from the bone-selective images. Ten healthy adult volunteers (six male, age 31.5 ± 10 years) and three pediatric patients (two male, ages 12 to 15 years) were scanned at 3 T. Clinical CT for the three patients were obtained for validation. Similarities in 3D skull reconstructions relative to clinical standard CT were evaluated based on the Dice similarity coefficient and Hausdorff distance. Craniometric measurements were used to assess geometric accuracy of the 3D skull renderings. RESULTS: The weighted least-squares method produces images with enhanced bone specificity, suppression of soft tissue, and separation from air at the sinuses when validated against CT in pediatric patients. Dice similarity coefficient overlap was 0.86 ± 0.05, and the 95th percentile Hausdorff distance was 1.77 ± 0.49 mm between the full-skull binary masks of the optimized UTE and CT in the testing dataset. CONCLUSION: An optimized MRI acquisition, reconstruction, and segmentation workflow for craniofacial imaging was developed.

Intradiploic epidermoid cyst in the skull: Case report and systematic review.

Intradiploic epidermoid cysts are rare, benign tumors, accounting for less than 1% of all intracranial tumors. Due to their scarcity, we are reporting a case of an intradiploic epidermoid cyst and reviewing several similar cases in the literature to provide a better description of this tumor and analyze its clinical and radiological features. We conducted a search on the PubMed database for studies published between January 2010 and February 2023, including studies of nontraumatic and noniatrogenic calvarial cysts. We found a total of 34 studies and 41 patients, with an average patient age of 42.5 years. Common symptoms included painless masses, headaches, and seizures. The occipital, frontal, and parietal regions were the most common locations for these tumors. Some patients experienced complications such as otitis media, infection, or extension into the orbit and brain. Surgical resection was performed in all cases except for 2 patients with contraindications to surgery. Histological examination confirmed the diagnosis of an intradiploic epidermoid cyst. These cysts are rare skull lesions and can potentially cause neurological deficits due to their mass effect. If incompletely resected, they may also undergo malignant transformation. No single institution has accumulated enough cases to describe this rare tumor accurately. Therefore, through this review, we aim to highlight this tumor's epidemiological, clinical, and radiological features.

Surgical anatomy of the carotid sympathetic plexus in endoscopic endonasal approaches: strategies for preventing Horner syndrome.

OBJECTIVE: Endoscopic endonasal approaches (EEAs) specifically for procedures involving manipulation of the internal carotid artery (ICA), such as the transcavernous and translacerum approaches, confer a potential risk of carotid sympathetic plexus injury, potentially leading to postganglionic Horner syndrome. The primary aim of this study was to delineate the surgical anatomy of the carotid sympathetic plexus from an endoscopic endonasal perspective, offering insights to facilitate intraoperative anatomical identification and injury prevention. METHODS: A comprehensive dissection was conducted on 20 silicone-injected, lightly embalmed postmortem human heads. The segments, patterns, and surgical landmarks of the carotid sympathetic plexus were investigated in a stepwise manner. In addition, 3 illustrative cases highlighting the involvement of the carotid sympathetic plexus in EEAs are included to contextualize the anatomical findings. RESULTS: The carotid sympathetic plexus can be categorized into 3 segments: 1) the cavernous sinus (CS) segment, beginning at the upper surface of the petrolingual ligament and ascending anterosuperiorly along the inferior compartment of the CS (mean ± SD length 5 ± 0.5 mm); 2) the lacerum segment, starting at the exit of the petrous carotid canal and ascending laterally and vertically to the upper surface of the petrolingual ligament (mean ± SD length 10 ± 1 mm); and 3) the petrous segment, originating at the external opening of the carotid canal and terminating at the foramen lacerum (mean ± SD length 18 ± 1 mm). Two primary morphological patterns of the sympathetic plexus at the CS and lacerum segments were identified: a plexus-like pattern in 12 (30%) hemispheres, and a nerve-like pattern that was subcategorized as double (18 [45%] hemispheres) or single (10 [25%] hemispheres) trunks. Surgical strategies emphasize the importance of recognizing key landmarks when approaching the carotid sympathetic plexus, including the pterygosphenoidal triangle, lingual process, petrolingual ligament, lateral parasellar ligament, and abducens nerve. CONCLUSIONS: This article provides a comprehensive anatomical description of the carotid sympathetic plexus in EEAs, highlighting key anatomical segments and patterns for intraoperative identification. A better understanding of anatomical landmarks for the carotid sympathetic plexus could help reduce the incidence of postganglionic Horner syndrome, augmenting the safety and efficacy of endoscopic endonasal transcavernous surgery.

Meningioma En Plaque associated with Cerebrospinal Fluid Rhinorrhea: A Systematic Review of Literature with Case Presentation.

BACKGROUND: Meningiomas are the most frequently diagnosed benign intracranial tumors. However, meningioma en plaque (MEP) is a rare subset accounting for 2.5% of all meningiomas and is characterized by flat, carpet-like proliferation along the dura, typically arising in the spheno-orbital region; therefore, causes proptosis, decreased visual acuity, and orbital pain. We present a unique case of MEP presenting with cerebrospinal fluid (CSF) rhinorrhea and conduct a systematic review of literature. METHODS: Following PRISMA guidelines, a systematic search was conducted in PubMed and Embase databases. Keywords and standardized index terms related to MEP were used. The search was performed without restriction on the publication date. Screening, data extraction, and quality assessment were carried out. Data on demographics, clinical presentations, management modalities, and treatment outcomes were analyzed. RESULTS: The search yielded 487 titles, with 36 studies eligible for inclusion. A total of 530 patients with MEP were reported, with a mean age of 50.1±11.62 years. Proptosis was the most common symptom (95%), followed by visual impairment (57.3%), orbital pain (38.3%), ophthalmoplegia (28.6%), and headache (23%). Our patient represented the only case with a spontaneous CSF leak. Surgical resection was performed in 85%, adjuvant radiotherapy in 15.7%, and one patient received primary radiotherapy, while 8 patients were closely followed up with no intervention. CONCLUSION: MEP associated with spontaneous CSF rhinorrhea is extremely rare and poses diagnostic and therapeutic challenges. Conservative management for select cases of MEP can be a good choice, refraining the patient from surgical complications, especially for difficult-access skull base areas.

Uncomplicated linear skull fractures in the paediatric population: a retrospective observational study in a UK Major Trauma Centre.

PURPOSE: National Institute of Clinical Excellence (NICE) guidelines advise that paediatric patients with linear skull fractures do not require admission in the absence of intracranial injury. Despite this, a period of inpatient neuro-observation has become the standard advice and practice in the UK for fear of deterioration. Our experience is that these children rarely deteriorate or require neurosurgical intervention. The primary aim of this study was to describe the incidence of neurological deterioration in patients referred to our paediatric neurosurgery unit with linear skull fractures. METHODS: We identified all patients with a linear skull fracture referred to neurosurgery at a paediatric major trauma centre between 2018 and 2023. Patients with intracranial injury, skull base fracture or major trauma were excluded. Demographic and clinical data were collected. The primary outcome was deterioration which was defined as drop in Glasgow Coma Scale (GCS) score, unplanned repeat cranial imaging, neurosurgical intervention performed, or the patient died. RESULTS: Two hundred and ninety-four patients were identified in our referral database. Infants were the age group most commonly referred (44.2%) and falls from under 2 m in height the most common mechanism of injury (71.4%). Ninety-seven children had specific advice documented regarding neuro-observation; of these, the majority (n = 53) were advised 24 hours of inpatient observation. No patients experienced deterioration. CONCLUSIONS: This is the largest cohort of linear skull fractures in children described in the UK. None of our patients experienced neurological deterioration, mirroring findings from international studies and supporting current NICE guidance. In addition, at a cost of £360 per 24-hour admission, this has a cost implication for a resource-scarce NHS. We propose that UK trauma networks should devise protocols to support the safe discharge from ED of such patients without the need for discussion with a neurosurgical department.

Management of large Trigeminal Schwannoma: long-term oncologic and functional outcome from a multicentric retrospective cohort.

OBJECTIVE: Trigeminal schwannoma (TS), though a rare and benign tumor, becomes a significant surgical challenge due to its intricate location. This study aims to detail the long-term functional outcomes and tumor control post-surgical resection. METHOD: We analyzed a multicentric retrospective cohort of 39 patients operated on for a TS in five tertiary centers between January 1993 and July 2022. RESULTS: Six TS (15%) were in the middle fossa (type M), two (5%) in the posterior fossa (type P), and two (5%) were extracranial (type E). Twenty-nine (75%) were Dumbbell shape: Eighteen (47%) were MP type, seven (18%) were MPE type, and four (10%) were ME type. Fifth nerve symptoms were the foremost preoperative complaint: hypesthesia (51%), trigeminal neuralgia (36%), and paresthesia (30%). We report a favorable evolution course for 61% of preexisting deficits (half of patients with preoperative paresthesia and neuralgia improved while only 5% of preoperative hypesthesia improved). Postoperative hypesthesia was the most frequent de novo deficit 14 (74%) and resolved in solely half the cases. Various approaches were used according to tumor type. Gross total resection (GTR), Subtotal resection (STR), and partial resection (PR) were achieved in respectively 33% (N = 13), 10% (N = 4), and 56% (N = 22) of patients. The mean clinical and radiological FU was 63 months (12 - 283 months). GTR led to no sign of recurrence (mean FU: 60 months - range: 12-283 months). For STR or PR (67%): 23 (88%) were assigned to a Wait-&-rescan policy (WS group) which offered stability in 70% (N = 16). Three cases (8%) underwent a complementary GKS (GammaKnife) on the residual lesion (GK group) without tumor change. CONCLUSION: For large TS, the completeness of resection must consider the potential functional burden of surgery. With giant infiltrating lesions, a strategy of planned subtotal resection, complemented by radiosurgery, either complementary or uppon regrowth, may provide similar oncological outcomes.

The feasibility and clinical outcome of endoscopic transorbital transcavernous approaches with or without petrosectomy for petroclival lesions.

OBJECTIVE: Petroclival tumors such as petroclival meningiomas or trigeminal schwannomas extending to the posterior cranial fossa are challenging to treat due to their deep-seated location and proximity to critical neurovascular structures. This study aimed to evaluate the feasibility, safety, and clinical outcomes of endoscopic transorbital surgery for the resection of central skull base tumors involving the petroclival area. METHODS: The authors conducted a retrospective analysis of 32 patients with petroclival tumors including meningiomas and trigeminal schwannomas who underwent endoscopic transorbital surgery between September 2017 and December 2022. Preoperative clinical and radiological data were collected, and patients were followed up postoperatively for a median period of 34.7 months. Surgical technique, complications, and clinical outcomes were assessed. RESULTS: Endoscopic transorbital surgery provided a minimally invasive and direct corridor to the petroclival region. All 32 patients successfully underwent tumor resection, with gross-total or near-total tumor resection achieved in 28 patients. The mean tumor diameter was 3.5 cm. Based on tumor pathology, the endoscopic transorbital transcavernous trans-Meckel's cave approach (21 cases) or transorbital anterior transpetrosal approach (11 cases) was selected. The most common complication was facial paresthesia in 4 of 21 patients with trigeminal schwannomas and in 1 of 11 patients with petroclival meningiomas. Diplopia due to fourth cranial nerve injury occurred in 3 of 11 patients with petroclival meningiomas. Postoperative clinical improvement in neuralgic pain was observed in 3 of 4 patients. One patient developed a temporary facial palsy (House-Brackmann grade III) and another patient had transient paraparesis after removal of petroclival meningioma. CONCLUSIONS: Endoscopic transorbital surgery appears to be a safe and effective technique for the resection of petroclival lesions, offering excellent visualization and access to the tumor while minimizing morbidity. However, further studies with larger patient cohorts and longer follow-up are warranted to validate the long-term efficacy and safety of this approach. This study contributes to the growing body of evidence supporting the utility of endoscopic transorbital techniques in skull base surgery.

Development and validation of a predictive scoring model for complications following endoscopic endonasal skull base surgery.

OBJECTIVE: The endoscopic endonasal approach (EEA) has evolved into an established technique in skull base surgery. The authors previously examined 1002 EEA procedures and reported factors associated with postoperative complications. Here they report the development and validation of a scoring model based on risk factors to better predict complications following EEA. METHODS: The authors developed an optimized EEA scoring model for predicting postoperative complications as evidenced by the area under the receiver operating characteristic (AUROC) curve using their previously published data in addition to data collected from the subsequent 292 EEA procedures from years 2010-2020. The model was built systematically by evaluating the contributions that different variables had on the overall predictive ability of the model. The aim was to design a model containing as few variables as possible for practicality and to facilitate calculation and use at the bedside. The Clavien-Dindo grading system was used to classify complications into grades I-V based on the level of intervention that was required to manage the complication, with grades III-V considered to be higher-grade (i.e., those requiring reoperation or ICU-level care or death). RESULTS: The authors identified 1294 EEA operations performed between July 2010 and July 2020 that met their inclusion criteria. Higher-grade complications were identified following 135 EEA operations. The variables that were ultimately included in the model were age, BMI, operative time, meningioma, chordoma, expanded intradural approach, and nasoseptal flap use. The final model yielded an acceptable AUROC curve of 0.72 and predicted a stepwise increase in the rate of higher-grade complications as the score increased. A score of 0-2 (low) on the grading system was associated with an average complication rate of 5.1%. A score of 3-5 (medium) was associated with an average complication rate of 12.6%. A score of 6 or above (high) was associated with an average complication rate of 26%. CONCLUSIONS: This EEA complications scoring model accurately categorizes patients into low-, medium-, and high-risk groups with readily obtained variables. A high score in this complications model does not suggest that a patient is ineligible for surgery, but rather highlights the importance of thorough case selection, operating with caution, and appropriate preoperative counseling.

Biomimetic periosteum-bone scaffolds with codelivery of BMP-2 and PDGF-BB for skull repair.

Tissue engineering employs the use of bioactive materials to facilitate the filling and acceleration of bone defect healing, thereby introducing novel concepts to the field of in situ bone repair. Some studies have shown that periosteum plays an important role in bone regeneration and repair. In this study, biomimetic periosteum-bone scaffolds were prepared by depositing poly-L-lactic acid (PLLA) electrospun fibers on the surface of the gelatin/chitosan cryogel to mimic the bone and periosteum structure, respectively. To improve the bioactivity of the scaffold, bone morphogenetic protein-2 (BMP-2) was loaded into a loose porous mesh-like cryogel, while platelet-derived growth factor-BB (PDGF-BB) was encapsulated in the core of PLLA nanofibers with core-shell structure. Both of these two growth factors were released locally at the site of bone defect, where they exert a synergistic effect on osteogenesis, thereby greatly accelerating bone healing. The in vitro experiments demonstrated that the biomimetic periosteum-bone scaffolds exhibited favourable biocompatibility and osteogenesis ability. Furthermore, the in vivo experiments indicated that the composite scaffold repaired rat skull defects in a more rapid and effective manner. In conclusion, biomimetic periosteum-bone scaffolds with codelivery of BMP-2 and PDGF-BB shows significant potential for bone regeneration.

DEK::AFF2 Carcinoma of the Sinonasal Tract and Skull Base: A Comprehensive Review.

DEK::AFF2 carcinoma is an emerging entity of the sinonasal tract and skull base, commonly exhibiting exophytic and endophytic papillary growth, complex anastomosing trabeculae, monotonous cytomorphology, acantholytic change, and tumor-infiltrating neutrophils. A subset displays overt infiltration and high-grade features akin to non-keratinizing squamous cell carcinoma. Glandular differentiation may also be rarely present. The tumor shows frequent local recurrence and occasional distant metastasis. An accurate diagnosis requires the recognition of these key histologic features, followed by molecular confirmation. Recently, AFF2 immunohistochemistry has been demonstrated to be a sensitive and specific ancillary marker. This comprehensive review summarizes the current understanding of DEK::AFF2 carcinoma.

Application of electrospinning and 3D-printing based bilayer composite scaffold in the skull base reconstruction during transnasal surgery.

Skull base defects are a common complication after transsphenoidal endoscopic surgery, and their commonly used autologous tissue repair has limited clinical outcomes. Tissue-engineered scaffolds prepared by advanced techniques of electrostatic spinning and three-dimensional (3D) printing was an effective way to solve this problem. In this study, soft tissue scaffolds consisting of centripetal nanofiber mats and 3D-printed hard tissue scaffolds consisting of porous structures were prepared, respectively. And the two layers were combined to obtain bilayer composite scaffolds. The physicochemical characterization proved that the nanofiber mat prepared by polylactide-polycaprolactone (PLCL) electrospinning had a uniform centripetal nanofiber structure, and the loaded bFGF growth factor could achieve a slow release for 14 days and exert its bioactivity to promote the proliferation of fibroblasts. The porous scaffolds prepared with polycaprolactone (PCL), and hydroxyapatite (HA) 3D printing have a 300 µm macroporous structure with good biocompatibility. In vivo experiments results demonstrated that the bilayer composite scaffold could promote soft tissue repair of the skull base membrane through the centripetal nanofiber structure and slow-release of bFGF factor. It also played the role of promoting the regeneration of the skull base bone tissue. In addition, the centripetal nanofiber structure also had a promotional effect on the regeneration of skull base bone tissue.

Allometry of human calvaria bones during development from birth to 8 years of age shows a nonlinear growth pattern.

Pediatric skulls change rapidly in size and shape during development, especially for children up to 8 years of age. This project was developed to address the gap in understanding of the three-dimensional growth parameters of the human skull during this period and the impact these growth patterns have on fontanelle closure and suture formation. This study offers novel data on the dynamic changes in the anatomy of the skull with the intention of providing better guidance for pediatric surgical care. Craniometric landmarks defined on three-dimensional computed tomography reconstructions were used to map skull development in children aged 0 to 8 years old. A total of 364 datasets were analyzed and statistically representative 3D skulls with anatomical craniometric features such as head shape, bone size, suture and fontanelle closure time were generated for 17 age groups spanning birth to 8 years of age to provide a comprehensive neuroanatomical understanding of how the pediatric skull changes over time. This study indicates that the cranial bones follow a non-linear growth pattern, with the occipital and frontal bones driving the directionality of fontanelle closure and delivers a 3D visualization of the developmental characteristics of the skull providing a landmark resource for understanding the growth dynamics of the human skull. While clinical measurements remain valid approaches for the planning of surgical interventions, these 3D models may provide a more accurate planning paradigm.

Network Analysis of Past Presidents of the North American Skull Base Society.

Background Little is known about the relative contributions and interactions of the past presidents of the North American Skull Base Society (NASBS) and skull base centers. Objectives (1) Measure academic contributions of past presidents; (2) identify influential nodes of academic collaboration; (3) identify opportunities for future collaboration. Methods Peer-reviewed publications of past presidents of NASBS from 1964 to July 2019 were identified using Scopus author name search. Network structures were constructed and analyzed using the graph-tool python library to produce a weighted co-authorship network base and compute centrality measures. Girvan-Newman clustering was applied to identify community structure. Network maps were then produced using Gephi network visualization software with force-directed layout algorithms. Results The coauthor network of 29 presidents was fully connected, with a maximum shortest-path distance between presidents of 5. The mean number of connections from each node without respect to weighting was 5.31 (standard deviation [SD]: 3.53), and the mean number of connections with weighting was 8.40 (SD: 7.28). The number of unweighted connections ranged from 1 to 14 and weighted connections ranged from 0.25 to 24.7. Girvan-Newman clustering identified three communities with two that covered 93% of the network. The largest communities contained 14 and 13 presidents. The number of connections was correlated with h-index, both unweighted ( r 2 = 0.34) and weighted ( r 2 = 0.26). Conclusion Network mapping of past presidents of the NASBS helps to capture the history of the NASBS and reveals areas of concentration and influence within the specialty.

Anatomical Step-by-Step Dissection of Complex Skull Base Approaches for Trainees: Surgical Anatomy of the Endoscopic Endonasal Approach to the Anterior Cranial Fossa.

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.

A Comprehensive Analysis of Academic Attributes of the Presidents of the North American Skull Base Society.

Objectives Our objective was to elucidate the demographic, academic, and career attributes of North American Skull Base Society (NASBS) presidents and determine how leadership of this society has changed over time. Design Thirty-one NASBS presidents have served between 1990 and 2021. Demographic and scholarly variables were recorded from publicly available sources. To determine how trends in NASBS presidents have changed over time, linear and logistic regressions were conducted on continuous and categorical variables, respectively. Setting Virtual setting was used for this study. Participants There were no active participants in the study. Main Outcome Measures Academic metrics of NASBS presidents were the main outcome measure. Results NASBS presidents had a mean age of 53.3 ± 6.1 years at election and were all male. The most common institution at which former presidents trained ( n = 4) and practiced ( n = 3) was the University of Pittsburgh. Otolaryngologists comprised 41.9% ( n = 13) of the cohort, neurosurgeons made up 38.8% ( n = 12), and the remaining 19.3% ( n = 6) were from other specialties. NASBS presidents from neurosurgery ( p = 0.033) and other specialties ( p = 0.014) were more likely to hold the rank of chair compared with those from otolaryngology. Over time, there has been a linear increase in years of research experience at the time of election ( p = 0.048). There remains a lack of diversity of gender and race. Conclusion NASBS presidents have demonstrated increased research activity over time, favoring long-term academic careers. Knowledge of these trends and attributes, which demonstrate an increase in skull base literature, growth of the NASBS, and a need for increased diversity in the field, is important for stewarding the future of the NASBS and promoting equity.

Multidisciplinary Management of Lateral Skull Base Paragangliomas: A 20-Year Experience.

Objectives Paragangliomas of the lateral skull base are rare, largely benign, neuroendocrine tumors. Little evidence exists to support clinicians in the management of these tumors. The present study evaluates considerations in the multidisciplinary workup and management of paragangliomas affecting the lateral skull base. Methods A STrengthening the Reporting of OBservational studies in Epidemiology (STROBE) checklist compliant retrospective review of adult patients with lateral skull base paragangliomas over 20 years (2002-2021) was performed. Patient and tumor data were collected from patient health care records. Results Seventy patients were identified including 21 (30.0%) males and 49 (70.0%) females. The mean length of follow-up was 87.3 months (range: 12-239 months). Twenty-nine (41.4%) patients had Fisch A or B tumors. Overall, 57 patients (81.4%) were offered treatment upfront, with 13 patients (18.6%) initially undergoing active surveillance. Younger age and reduced American Society of Anesthesiologists (ASA) grade was significantly associated with a decision to offer treatment at presentation (both p = 0.03), while all patients with succinate dehydrogenase (SDH) mutations ( n = 10) and tumor secretion ( n = 4) were offered treatment. Patients with Fisch A/B tumors ( p = 0.01), cranial neuropathies ( p = 0.01), and smaller tumors ( p = 0.01) were more likely to undergo surgical resection. At the time of the last follow-up, the proportion of patients with a cranial neuropathy was notably lower in the observation (3/12, 25.0%) and radiotherapy (1/6, 16.7%) groups. Conclusion In our series, younger, fitter patients with SDH mutations, cranial neuropathies, or tumor secretion were more likely to be offered upfront treatment. There was a low incidence of new cranial neuropathy in the patients selected for observation during long-term follow-up.

Significant Underreporting of Preoperative Hyposmia in Patients Undergoing Endoscopic Skull Base Surgery: Discrepancies Between Subjective and Objective Measurements.

Objective The assessment of baseline olfactory function before endoscopic skull base surgery (ESBS) has been relatively limited compared with analysis before functional endoscopic sinus surgery (FESS). Our study addresses this knowledge gap, assessing preoperative olfactory function in ESBS and FESS and elucidating any differences. Study Design We conducted a retrospective review of patients undergoing anterior ESBS or FESS at a single institution between 2021 and 2022. We included 171 patients and compared their reported and measured preoperative olfactory function using the Sino-Nasal Outcome Test questionnaire and the 40-item University of Pennsylvania Smell Identification Test. Results Of the 171 patients included in this study, 30% of patients underwent ESBS and 70% underwent FESS. Of all patients, only 57% correctly reported their objective preoperative olfactory function. Of the 36 ESBS patients with measured preoperative hyposmia, only 31% correctly reported hyposmia, while 69% incorrectly reported normosmia. This distribution significantly differs ( p < 0.0001) from the FESS subset (89 patients), with 64% correctly reporting hyposmia and 36% incorrectly reporting normosmia. Conclusion Our analysis demonstrates higher than anticipated underreporting of preoperative hyposmia in patients undergoing ESBS as well as discrepancies between subjective and objective olfactory functions in the FESS population. The results highlight several gaps in knowledge regarding perioperative olfactory function that would be best examined with more thorough pre- and postoperative objective olfactory testing. This analysis demonstrates significant prognostic uncertainty for patients and providers and creates significant medicolegal uncertainty regarding the appropriate attribution of postoperative olfactory loss in cases without objective preoperative testing.

Anatomical Step-by-Step Dissection of Complex Skull Base Approaches for Trainees: Lateral Supraorbital Approach with Expanded Indications.

Objectives The lateral supraorbital (LSO) approach is a less-invasive alternative to the pterional craniotomy that provides rapid transsylvian access. Establishing familiarity with the LSO technique and its features as compared with other anterolateral approaches is an important component of advanced skull base training. We present a step-by-step demonstration of the LSO approach using cadaveric dissection in a manner that is digestible for trainees at various levels. Design This is anatomic step-by-step dissection and representative case series. Setting This study was carried out in the cadaveric dissection laboratory. Participants A formalin-fixed, latex-injected cadaveric head specimen was dissected under microscopic magnification by a neurosurgery resident under faculty supervision. Following dissection, representative case applications were reviewed. Main Outcome Measures Dissection and case illustration were the main outcome measures. Results A single-layer myocutaneous flap is developed, and a single-burr-hole technique is used, followed by extensive drilling of the sphenoid wing. The dura is opened in a C-shaped fashion centered on the Sylvian fissure, exposing the inferior frontal and superior temporal lobes. Labeled photographs of dissections with pertinent anatomical structures are presented. Three case examples illustrating the versatility of the LSO approach, including the resection of a large pituitary adenoma, an inferior frontal melanoma metastasis presenting to the Sylvian surface, and a frontoinsular low-grade glioma, are reviewed. Conclusion As compared with the pterional craniotomy, the LSO approach involves a shorter incision, smaller craniotomy, and faster exposure; it can be conveniently tailored to various indications. Understanding the step-by-step dissection and indications of the LSO approach is of paramount importance to neurosurgery trainees.

Functional and Radiographic Outcomes of Cavernous Meningiomas Based on Treatment Modality.

Introduction Cavernous sinus meningiomas (CSMs) are challenging given their proximity to neurovascular structures. Treatments include surgery, radiation, or observation. There are little data comparing outcomes based on treatment. This study presents the radiographic and functional outcomes of patients with CSMs treated with either radiation, surgical resection ± radiation, or radiographic surveillance. Methods This is a retrospective review of adults diagnosed with CSMs between 2009 and 2016. Patient and tumor characteristics and outcomes were obtained from chart review. Categorical and continuous variables were compared via nonparametric tests. Results Sixty-four patients were diagnosed with CSMs between 2009 and 2016. Thirty-four had radiation. Thirteen had surgical resection with adjuvant radiation and 14 underwent observation. Fifty-four patients had a pretreatment deficit (84.4%). Radiographic control rates were 100% in the surgery group, 97.1% in the radiation group, 69.2% in the surgery + adjuvant radiation, and 90.9% in the observation group ( p = 0.035). The radiotherapy group had complete improvement of symptoms in 32.4% and partial improvement in 23.1% ( p = 0.022). In the surgery group, one patient had complete resolution of symptoms (6.3%), eight had partial improvement (50.0%), and seven patients had no improvement ( p = 0.002). Surgery was more likely to lead to progression of symptoms posttreatment (odds ratio: 5.16, confidence interval: 1.309-20.34) ( p = 0.019). Conclusion Radiation has an excellent rate of radiographic control. Surgery is an option for large or symptomatic lesions. The role of surgery is primarily for vision preservation, decompression of cranial nerves, and tumor debulking and patients should be counseled extensively regarding treatment goals and expectations prior to surgery.