The Apple Vision Pro as a Neurosurgical Planning Tool: A Case Report

With its recent release, the Apple Vision Pro (Apple Inc., Cupertino, CA) represents a promising technological advancement of mixed reality in the field of neurosurgery and medicine more broadly. With all new technologies, it is critical to facilitate early use and assessment of the technology to facilitate adoption by the larger medical community. A 44-year-old female with a history of ruptured intracranial aneurysm status post anterior communicating artery aneurysm clipping presented with worsened confusion and intermittent headache. CT imaging revealed evidence of hydrocephalus due to the malfunction of a previous right parietal ventriculoperitoneal (VP) shunt. Prior to the case, the Apple Vision Pro was used in the operating room to visualize and interact with a 3D model of the patient's anatomy for the patient undergoing a VP shunt placement. A visualization of the 3D model through the headset was used to plan the approach and entry point. At the conclusion of the procedure, all clinicians and operating staff who used the technology for planning completed a survey about their initial impressions of the headset. Overall, users felt the 3D models felt realistic (4.5/5), that the display of the user's real-world view felt natural (4.3/5), and that the headset did not cause eye strain or fatigue (4.5/5). The majority of users responded that they would continue to use the headset for cases (4/5). This represents one of the first known clinical uses of the Apple Vision Pro. It is a cutting-edge technology that will likely provide immense value for healthcare providers as it becomes more integrated into clinical care.

Augmented Reality-Assisted Placement of Ommaya Reservoir for Cyst Aspiration: A Case Report

Image guidance technologies can significantly improve the accuracy and safety of intracranial catheter insertions. Augmented reality (AR) allows surgeons to visualize 3D information overlaid onto a patient's head. As such, AR has emerged as a novel image guidance technology that offers unique advantages when navigating intracranial targets. A 71-year-old woman with a history of brain metastasis from breast cancer and prior resection surgery and chemotherapy presented with altered mental status and generalized weakness worse on her left side. Magnetic resonance imaging (MRI) demonstrated right frontotemporoparietal edema with a contrast-enhancing mass. MR perfusion confirmed an active tumor with an enlarging right temporal pole cyst. A cyst aspiration was performed via Ommaya reservoir placement. Neuro-navigation (BrainLab, Munich, Germany) and AR navigation were used to plan the trajectory from the temporal gyrus to the cyst. Post-operative computed tomography (CT) demonstrated good placement of the reservoir, reconstitution of the temporal horn of the lateral ventricle with decreased external mass effect, and no areas of hemorrhage. AR has tremendous potential in the field of neurosurgery for improving the accuracy and safety of procedures. This case demonstrates an encouraging application of AR and can serve as an example to drive expanded clinical use of this technology.

Use of tubular retractors to access deep brain lesions: A case series

BACKGROUND

Deep-seated intracranial lesions can be accessed using blade retractors that may disrupt white matter tracts, exert pressure on adjacent tissue, and lead to post-operative venous injury. Tubular retractors may minimize disruption to white matter tracts by radially dispersing pressure onto surrounding tissue. This study characterizes perioperative outcomes in patients undergoing biopsy or resection of intracranial pathologies using tubular retractors.

METHODS

Adult patients (≥18 years) undergoing neurosurgical intervention using tubular retractors at a single health system (January 2016-February 2022) were identified through chart review. Demographics, disease characteristics, management data, and clinical outcomes were collected.

RESULTS

A total of 49 patients were included; 23 (47%) had primary brain tumors, 8 (16%) metastases, 6 (12%) intracranial hemorrhage (ICH), 5 (10%) cavernomas, and 7 (14%) other pathologies. Lesions were located subcortically (n = 19, 39%), intraventricularly (n = 15, 31%), and in deep gray matter (n = 11, 22%). Gross total resection (GTR) or near GTR was achieved in 21 of 26 (80.8%) patients with intracranial lesions where GTR was the goal of surgery; 10 of 11 (90.9%) biopsies in patients with masses were diagnostic. Five of six (83.3%) ICHs were totally or near totally evacuated. Seventeen patients (35%) had major complications post-operatively. The most common complications were DVT/PE (n = 7, 14%) and seizures (n = 6, 12%). For patients who experienced post-operative seizures, 3 had seizures preoperatively and 1 had seizures in the context of electrolyte derangements. No patients died of post-operative complications.

CONCLUSION

This operative approach may facilitate safe and efficacious biopsy or resection of deep-seated intracranial pathologies.

Patient reported outcomes and treatment satisfaction in patients with cushing syndrome

PURPOSE

Cushing Syndrome (CS) is a rare endocrine disorder associated with physical and mental symptoms that can drastically affect quality of life (QoL). This study characterizes QoL in patients with CS, describes their treatment experiences, and identifies patient subsets associated with decreased QoL or shared impressions of treatment.

METHODS

A 136-question survey addressing QoL factors and treatment experiences was completed by adult patients with CS from the Cushing Support and Research Foundation. Patient demographics, tumor characteristics, and treatment information were collected. Bivariate analyses were conducted to determine if patients' symptoms or treatment experiences were significantly associated with demographics or other variables.

RESULTS

A total of 178 patients, predominantly female (94%) with mean age 53 years, completed the survey. Anxiety and/or depression (n = 163, 94%), loss of physical strength (n = 164, 93%), loneliness (n = 156, 90%), fatigue from treatment (n = 142, 89%), memory loss (n = 153, 88%), insomnia (n = 144, 83%), and pain (n = 141, 83%) were symptoms most commonly experienced by respondents. Patients experiencing delay of diagnosis >10 years were more likely to have suicidal thoughts (p = 0.002). Younger patients were more likely to express concerns about hair loss (p = 0.007), loneliness (p = 0.025), pain (p = 0.004), or the impact of CS on their marriage (p = 0.039) or children (p = 0.024).

CONCLUSION

This survey demonstrates CS impacts patients across many dimensions, emphasizing the need for holistic support. We identified patient subsets in which QoL may be improved with additional patient resources or provider attention.

Current and Future Frontiers of Molecularly Defined Oligodendrogliomas

Oligodendrogliomas are a subtype of adult diffuse glioma characterized by their better responsiveness to systemic chemotherapy than other high-grade glial tumors. The World Health Organization (WHO) 2021 brain tumor classification highlighted defining molecular markers, including 1p19q codeletion and IDH mutations which have become key in diagnosing and treating oligodendrogliomas. The management for patients with oligodendrogliomas includes observation or surgical resection potentially followed by radiation and chemotherapy with PCV (Procarbazine, Lomustine, and Vincristine) or Temozolomide. However, most of the available research about oligodendrogliomas includes a mix of histologically and molecularly diagnosed tumors. Even data driving our current management guidelines are based on post-hoc subgroup analyses of the 1p19q codeleted population in landmark prospective trials. Therefore, the optimal treatment paradigm for molecularly defined oligodendrogliomas is incompletely understood. Many questions remain open, such as the optimal timing of radiation and chemotherapy, the response to different chemotherapeutic agents, or what genetic factors influence responsiveness to these agents. Ultimately, oligodendrogliomas are still incurable and new therapies, such as targeting IDH mutations, are necessary. In this opinion piece, we present relevant literature in the field, discuss current challenges, and propose some studies that we think are necessary to answer these critical questions.

Clinical features and surgical outcomes of intracranial and spinal cord subependymomas

OBJECTIVE

Subependymomas are low-grade ependymal tumors whose clinical characteristics, radiographic features, and postsurgical outcomes are incompletely characterized due to their rarity. The authors present an institutional case series and a systematic literature review to achieve a better understanding of subependymomas.

METHODS

Adult patients with histologically confirmed subependymoma or mixed subependymoma-ependymoma surgically treated at a tertiary hospital between 1992 and 2020 were identified. A systematic literature review of the PubMed, Embase, Web of Science, and Google Scholar databases from inception until December 4, 2020, was conducted according to PRISMA guidelines. Data extracted from both groups included demographics, radiographic features, tumor characteristics, management, and follow-up variables.

RESULTS

Forty-eight unique patients with subependymoma were identified by chart review; of these patients, 8 (16.7%) had mixed subependymoma-ependymoma tumors. The median age at diagnosis was 49 years (IQR 19.8 years), and 26 patients (54.2%) were male. Forty-two patients (87.5%) had intracranial subependymomas, and 6 (12.5%) had spinal tumors. The most common presentation was headache (n = 20, 41.7%), although a significant number of tumors were diagnosed incidentally (n = 16, 33.3%). Among the 42 patients with intracranial tumors, 15 (35.7%) had hydrocephalus, and the most common surgical strategy was a suboccipital approach with or without C1 laminectomy (n = 26, 61.9%). Gross-total resection (GTR) was achieved in 33 cases (68.7%), and 2 patients underwent adjuvant radiotherapy. Most patients had no major postsurgical complications (n = 34, 70.8%), and only 1 (2.1%) had recurrence after GTR. Of 2036 reports initially identified in the systematic review, 39 were eligible for inclusion, comprising 477 patients. Of 462 patients for whom tumor location was reported, 406 (87.9%) were intracranial, with the lateral ventricle as the most common location (n = 214, 46.3%). Spinal subependymomas occurred in 53 patients (11.5%), with 3 cases (0.6%) in multiple locations. Similar to the case series at the authors' institution, headache was the most common presenting symptom (n = 231, 54.0%) among the 428 patients whose presentation was reported. Twenty-seven patients (6.3%) were diagnosed incidentally, and 36 cases (8.4%) were found at autopsy. Extent of resection was reported for 350 patients, and GTR was achieved in 250 (71.4%). Fifteen of 337 patients (4.5%) had recurrence or progression.

CONCLUSIONS

The authors' case series and literature review demonstrate that patients with subependymoma are well managed with resection and generally have a favorable prognosis.

The Suprasellar Meningioma Patient-Reported Outcome Survey: a disease-specific patient-reported outcome measure for resection of suprasellar meningioma

OBJECTIVE

Suprasellar meningioma resection via either the transcranial approach (TCA) or the endoscopic endonasal approach (EEA) is an area of controversy and active evaluation. Skull base surgeons increasingly consider patient-reported outcomes (PROs) when choosing an approach. No PRO measure currently exists to assess quality of life for suprasellar meningiomas.

METHODS

Adult patients undergoing suprasellar meningioma resection between 2013 and 2019 via EEA (n = 14) or TCA (n = 14) underwent semistructured interviews. Transcripts were coded using a grounded theory approach to identify themes as the basis for a PRO measure that includes all uniquely reported symptoms. To assess content validity, 32 patients and 15 surgeons used a Likert scale to rate the relevance of items on the resulting questionnaire and the general Patient-Reported Outcomes Measurement Information System-29 (PROMIS29). The mean scores were calculated for all items and compared for TCA versus EEA patient cohorts by using unpaired t-tests. Items on either questionnaire with mean scores ≥ 2.0 from patients were considered meaningful and were aggregated to form the novel Suprasellar Meningioma Patient-Reported Outcome Survey (SMPRO) instrument.

RESULTS

Qualitative analyses resulted in 55 candidate items. Relative to patients who underwent the EEA, those who underwent the TCA reported significantly worse future outlook before surgery (p = 0.01), tiredness from medications 2 weeks after surgery (p = 0.001), and word-finding and memory difficulties 3 months after surgery (p = 0.05 and < 0.001, respectively). The items that patients who received a TCA were most concerned about included medication-induced lethargy after surgery (2.9 ± 1.3), blurry vision before surgery (2.7 ± 1.5), and difficulty reading due to blurry vision before surgery (2.7 ± 2.7). Items that patients who received an EEA were most concerned about included blurry vision before surgery (3.5 ± 1.3), difficulty reading due to blurry vision before surgery (2.4 ± 1.3), and problems with smell postsurgery (2.9 ± 1.3). Although surgeons overall overestimated how concerned patients were about questionnaire items (p < 0.0005), the greatest discrepancies between patient and surgeon relevance scores were for blurry vision pre- and postoperatively (p < 0.001 and < 0.001, respectively) and problems with taste postoperatively (p < 0.001). Seventeen meningioma-specific items were considered meaningful, supplementing 8 significant PROMIS29 items to create the novel 25-item SMPRO.

CONCLUSIONS

The authors developed a disease- and approach-specific measure for suprasellar meningiomas to compare quality of life by operative approach. If demonstrated to be reliable and valid in future studies, this instrument may assist patients and providers in choosing a personalized surgical approach.

ABBREVIATIONS

EEA = endoscopic endonasal approach; GTR = gross-total resection; PRO = patient-reported outcome; PROMIS29 = Patient-Reported Outcomes Measurement Information System-29; QOL = quality of life; SMPRO = Suprasellar Meningioma Patient-Reported Outcome Survey; TCA = transcranial approach.

A Crowdsourced Consensus on Supratotal Resection Versus Gross Total Resection for Anatomically Distinct Primary Glioblastoma

BACKGROUND

Gross total resection (GTR) of contrast-enhancing tumor is associated with increased survival in primary glioblastoma. Recently, there has been increasing interest in performing supratotal resections (SpTRs) for glioblastoma.

OBJECTIVE

To address the published results, which have varied in part due to lack of consensus on the definition and appropriate use of SpTR.

METHODS

A crowdsourcing approach was used to survey 21 neurosurgical oncologists representing 14 health systems nationwide. Participants were presented with 11 definitions of SpTR and asked to rate the appropriateness of each definition. Participants reviewed T1-weighed postcontrast and fluid-attenuated inversion-recovery magnetic resonance imaging for 22 anatomically distinct glioblastomas. Participants were asked to assess the tumor location's eloquence, the perceived equipoise of enrolling patients in a randomized trial comparing gross total to SpTR, and their personal treatment plans.

RESULTS

Most neurosurgeons surveyed (n = 18, 85.7%) agree that GTR plus resection of some noncontrast enhancement is an appropriate definition for SpTR. Overall, moderate inter-rater agreement existed regarding eloquence, equipoise, and personal treatment plans. The 4 neurosurgeons who had performed >10 SpTRs for glioblastomas in the past year were more likely to recommend it as their treatment plan (P < .005). Cases were divided into 3 anatomically distinct groups based upon perceived eloquence. Anterior temporal and right frontal glioblastomas were considered the best randomization candidates.

CONCLUSION

We established a consensus definition for SpTR of glioblastoma and identified anatomically distinct locations deemed most amenable to SpTR. These results may be used to plan prospective trials investigating the potential clinical utility of SpTR for glioblastoma.

Predicting High-Value Care Outcomes After Surgery for Skull Base Meningiomas

BACKGROUND

Although various predictors of adverse postoperative outcomes among patients with meningioma have been established, research has yet to develop a method for consolidating these findings to allow for predictions of adverse health care outcomes for patients diagnosed with skull base meningiomas. The objective of the present study was to develop 3 predictive algorithms that can be used to estimate an individual patient's probability of extended length of stay (LOS) in hospital, experiencing a nonroutine discharge disposition, or incurring high hospital charges after surgical resection of a skull base meningioma.

METHODS

The present study used data from patients who underwent surgical resection for skull base meningiomas at a single academic institution between 2017 and 2019. Multivariate logistic regression analysis was used to predict extended LOS, nonroutine discharge, and high hospital charges, and 2000 bootstrapped samples were used to calculate an optimism-corrected C-statistic. The Hosmer-Lemeshow test was used to assess model calibration, and P < 0.05 was considered statistically significant.

RESULTS

A total of 245 patients were included in our analysis. Our cohort was mostly female (77.6%) and white (62.4%). Our models predicting extended LOS, nonroutine discharge, and high hospital charges had optimism-corrected C-statistics of 0.768, 0.784, and 0.783, respectively. All models showed adequate calibration (P>0.05), and were deployed via an open-access, online calculator: https://neurooncsurgery3.shinyapps.io/high_value_skull_base_calc/.

CONCLUSIONS

After external validation, our predictive models have the potential to aid clinicians in providing patients with individualized risk estimation for health care outcomes after meningioma surgery.

RADT-27. ASSOCIATION BETWEEN ADJUVANT RADIATION THERAPY AND OVERALL SURVIVAL IN PLEOMORPHIC XANTHOASTROCYTOMA

Pleomorphic Xanthoastrocytoma (PXA) is a low-grade central nervous system (CNS) tumor with a generally favorable prognosis. However, due to its rarity, optimal adjuvant treatment guidelines have not been established by large scale studies. In this study, we investigated the effect of adjuvant radiation therapy (RT) on overall survival (OS) in adult patients with PXA to help address this unanswered question. The National Cancer Database (NCDB) was used to identify adult patients (age 18 years old) diagnosed with histologically confirmed PXA (2004-2016). Patient demographics, tumor characteristics, and treatment information were collected. Kaplan-Meier curves were generated to study OS, and factors that affected OS were identified using a multivariate Cox proportional hazards (CPH) model. A total of 546 patients were identified. The average age of patients at diagnosis was 36.6 years old, and overall median survival was 128.6 months. RT was used to treat 179 (33.3%) patients. Those who received RT had a shorter median OS (33.3 months) compared to those who did not (&gt; 128.6 months, p &lt; 0.001). Our multivariate model demonstrated receiving RT was independently associated with a significantly higher risk of death (hazard ratio [HR]=4.28, 95% confidence interval [CI] = 1.77-10.38, p = .0013). Patients ≥ 65 years of age also demonstrated significantly higher risk of death (HR = 2.20, CI = 1.54-4.16, p = 0.006) and had a decreased median OS (26.0 months). In adults with PXA, treatment with RT is independently associated with a significantly higher risk of mortality. The routine use of this modality in treating PXA warrants further study.

SURG-21. A CROWDSOURCED CONSENSUS ON SUPRATOTAL RESECTION VERSUS GROSS TOTAL RESECTION FOR ANATOMICALLY DISTINCT PRIMARY GLIOBLASTOMA

Gross total resection (GTR) of contrast-enhancing tumor is associated with significantly increased overall survival in primary glioblastoma (GBM). Even when achieved, recurrence is likely, in part due to malignant cells infiltrating outside enhanced regions. Subsequently, there has been increasing interest in performing supratotal resections (SpTRs) for GBM. Published results have varied in part due to a lack of consensus on the definition of SpTR in GBM and its appropriate use. A crowdsourcing approach was used to survey 21 academic neurosurgical oncologists representing 13 health systems nationwide. Participants’ demographics including fellowship training status, years of experience, and operative volume with various techniques was collected. Participants were presented with 11 definitions of SpTR from published, peer-reviewed studies and asked to rate the appropriateness of each definition. Subsequently, participants reviewed T1-weighed post-contrast and FLAIR MR imaging videos in the axial, coronal, and sagittal planes for 22 GBMs. Participants were asked to assess eloquence of the tumor’s location, perceived equipoise of enrolling patients in a randomized clinical trial comparing GTR to SpTR, and their own personal surgical treatment plans. Most neurosurgeons surveyed (n=18, 85.7%) agree or strongly agree that GTR plus resection of some non-contrast enhancement is an appropriate definition for SpTR. Overall, there was only moderate inter-rater agreement, measured using sample variance and the index of qualitative variation, regarding eloquence, equipoise, and personal treatment plans. Neurosurgeons who performed more than 10 SpTRs for GBMs in the past year were more likely than counterparts to recommend it as their personal treatment plan (p&lt; 0.005). Anterior temporal and right frontal GBMs were considered the best randomization candidates. We established a consensus definition for SpTR of GBM and identified anatomically distinct locations deemed most amenable to SpTR. These results will be used to plan prospective trials further investigating the potential clinical utility of SpTR for GBMs.

Association between adjuvant radiation therapy and overall survival in Pleomorphic Xanthoastrocytoma

BACKGROUND

Pleomorphic Xanthoastrocytoma (PXA) is a low-grade central nervous system (CNS) tumor with a generally favorable prognosis. However, due to its rarity, optimal adjuvant treatment guidelines have not been established by large scale studies. In this study, we investigated the effect of adjuvant radiation therapy (RT) on overall survival (OS) in adult patients with PXA to help address this unanswered question.

METHODS

The National Cancer Database (NCDB) was used to identify adult patients (age ≥ 18 years old) diagnosed with histologically confirmed grade II PXA (2004-2016). Patient demographics, tumor characteristics, and treatment information were collected. Kaplan-Meier curves were generated to study OS, and factors that affected OS were identified using a multivariate Cox proportional hazards (CPH) model.

RESULTS

A total of 546 patients were identified. The average age of patients at diagnosis was 36.6 years old, and overall median survival was 128.6 months. RT was used to treat 179 (33.3 %) patients. Those who received RT had a shorter median OS (33.3 months) compared to those who did not (>128.6 months, p < 0.001). Our multivariate model demonstrated receiving RT was independently associated with a significantly higher risk of death (hazard ratio [HR] = 4.28, 95 % confidence interval [CI] = 1.77-10.38, p = .0013). Patients ≥65 years of age also demonstrated significantly higher risk of death (HR = 2.20, CI = 1.54-4.16, p = .006) and had a decreased median OS (26.0 months).

CONCLUSION

In adults with PXA, treatment with RT is independently associated with a significantly higher risk of mortality. The routine use of this modality in treating PXA warrants further study.