Outcome of elderly patients undergoing awake-craniotomy for tumor resection

Healthcare spending versus mortality in central nervous system cancer: Has anything changed?

Background

The financial implications of central nervous system (CNS) cancers are substantial, not only for the healthcare service and payers, but also for the patients who bear the brunt of direct, indirect, and intangible costs. This study sought to investigate the impact of healthcare spending on CNS cancer survival using recent US data.

Methods

This study used public data from the Disease Expenditure Project 2016 and the Global Burden of Disease Study 2019. The primary outcome was the annual healthcare spending trend from 1996 and 2016 on CNS tumors adjusted for disease prevalence, alongside morbidity and mortality. Secondary outcomes included drivers of change in healthcare expenditures for CNS cancers. Subgroup analysis was performed stratified by age group, expenditure type, and care type provided.

Results

There was a significant increase in total healthcare spending on CNS cancers from $2.72 billion (95% CI: $2.47B to $2.97B) in 1996 to $6.85 billion (95% CI: $5.98B to $7.57B) in 2016. Despite the spending increase, the mortality rate per 100 000 people increased, with 5.30 ± 0.47 in 1996 and 7.02 ± 0.47 in 2016, with an average of 5.78 ± 0.47 deaths per 100 000 over the period. The subgroups with the highest expenditure included patients aged 45 to 64, those with private insurance, and those receiving inpatient care.

Conclusions

This study highlights a significant rise in healthcare costs for CNS cancers without corresponding improvements in mortality rate, indicating a mismatch of healthcare spending, contemporary advances, and patient outcomes as it relates to mortality.

Toward a systematic grading for the selection of patients to undergo awake surgery: identifying suitable predictor variables

Background

Awake craniotomy is the standard of care for treating language eloquent gliomas. However, depending on preoperative functionality, it is not feasible in each patient and selection criteria are highly heterogeneous. Thus, this study aimed to identify broadly applicable predictor variables allowing for a more systematic and objective patient selection.

Methods

We performed post-hoc analyses of preoperative language status, patient and tumor characteristics including language eloquence of 96 glioma patients treated in a single neurosurgical center between 05/2018 and 01/2021. Multinomial logistic regression and stepwise variable selection were applied to identify significant predictors of awake surgery feasibility.

Results

Stepwise backward selection confirmed that a higher number of paraphasias, lower age, and high language eloquence level were suitable indicators for an awake surgery in our cohort. Subsequent descriptive and ROC-analyses indicated a cut-off at ≤54 years and a language eloquence level of at least 6 for awake surgeries, which require further validation. A high language eloquence, lower age, preexisting semantic and phonological aphasic symptoms have shown to be suitable predictors.

Conclusion

The combination of these factors may act as a basis for a systematic and standardized grading of patients' suitability for an awake craniotomy which is easily integrable into the preoperative workflow across neurosurgical centers.

Early Postoperative Seizures Following Awake Craniotomy and Functional Brain Mapping for Lesionectomy

OBJECTIVE

Awake craniotomy with electrocorticography (ECoG) and direct electrical stimulation (DES) facilitates lesionectomy while avoiding adverse effects. Early postoperative seizures (EPS), occurring within 7 days following surgery, can lead to morbidity. However, risk factors for EPS after awake craniotomy including clinical and ECoG data are not well defined.

METHODS

We retrospectively studied the incidence and risk factors of EPS following awake craniotomy for lesionectomy, and report short-term outcomes between January 1, 2020, and December 31, 2022.

RESULTS

We included 138 patients (56 female) who underwent 142 awake craniotomies, average age was 50.78 ± 15.97 years. Eighty-eight (63.7%) patients had a preoperative history of tumor-related epilepsy treated with antiseizure medication (ASM), 12 (13.6%) with drug-resistance. All others (36.3%) received ASM prophylaxis with levetiracetam perioperatively and continued for 14 days. An equal number of cases (71) each utilized a novel circle grid or strip electrodes for ECoG. There were 31 (21.8%) cases of intraoperative seizures, 16 with EPS (11.3%). Acute abnormality on early postoperative neuroimaging (P = 0.01), subarachnoid hemorrhage (P = 0.01), young age (P = 0.01), and persistent postoperative neurologic deficits (P = 0.013) were associated with EPS. Acute abnormality on neuroimaging remained significant in multivariate analysis. Outcomes during hospitalization and early outpatient follow up were worse with EPS.

CONCLUSIONS

We report novel findings using ECoG and clinical features to predict EPS, including acute perioperative brain injury, persistent postoperative deficits and young age. Given worse outcomes with EPS, clinical indicators for EPS should alert clinicians of potential need for early postoperative EEG monitoring and perioperative ASM adjustment.

Risk Factors and Characteristics of Intraoperative Seizures During Awake Craniotomy: A Retrospective Cohort Study of 562 Consecutive Patients With a Space-occupying Brain Lesion

INTRODUCTION

Intraoperative seizures (IOSs) during awake craniotomy (AC) are associated with significant morbidity. The reported incidence of IOS is between 3% and 30%. The aim of this study was to identify risk factors for IOS during AC for elective resection or biopsy of a space-occupying brain lesion.

METHODS

In this retrospective study, we reviewed the records of all awake craniotomies performed by a single neurosurgeon at a single university hospital between July 2006 and December 2018. IOS was defined as a clinically apparent seizure that occurred in the operating room and was documented in the medical records. Explanatory variables were chosen based on previously published literature on risk factors for IOS.

RESULTS

Five hundred and sixty-two patients had a total of 607 AC procedures during the study period; 581 cases with complete anesthesia records were included in analysis. Twenty-nine (5.0%) IOS events were reported during 29 (5%) awake craniotomies. Most seizures (27/29; 93%) were focal in nature and did not limit planned intraoperative stimulation mapping. Variables associated with IOS at a univariate P -value <0.1 (frontal location of tumor, preoperative radiotherapy, preoperative use of antiepileptic drugs, intraoperative use of dexmedetomidine, and intraoperative stimulation mapping) were included in a multivariable logistic regression. Frontal location of tumor (adjusted odds ratio: 5.68, 95% confidence interval: 2.11-15.30) and intraoperative dexmedetomidine use (adjusted odds ratio: 2.724, 95% confidence interval: 1.24-6.00) were independently associated with IOS in the multivariable analysis.

CONCLUSIONS

This study identified a low incidence (5%) of IOS during AC. The association between dexmedetomidine and IOS should be further studied in randomized trials as this is a modifiable risk factor.

Monitored Anesthesia Care Protocol for Awake Craniotomy and Patient's Perspective on the Procedure

OBJECTIVE

There is ongoing discussion on pros and cons in terms of different anesthesia protocols for awake craniotomy (AC) with direct brain stimulation. The aim of this study is to share our anesthesia protocol and present our patients' perspectives.

METHODS

We conducted an analysis of prospectively collected data from 53 (54 procedures) consecutive patients. Most of the patients (50) underwent surgery due to primary brain lesions. Eight procedures were performed in patients with lesions in the nondominant hemisphere for language. Four of all procedures were reoperations, and one patient was operated on in awake conditions twice. The psychological evaluation of patients was performed 2 times: 2 days before and after surgery. A visual analog scale for pain and stress levels as well as structured interviews was used.

RESULTS

Most patients tolerated ACwell. Patients reported that discomfort was mostly related to urinary catheter insertion, head holder placement, and temporal muscle detachment in cases of frontotemporal craniotomies. The intensity of stress measured with the visual analog scale before surgery was negatively associated with age and positively correlated with stress experienced in the operating room. In all patients, we were able to finish the procedure according to the monitored anesthesia care protocol without the need for conversion to general anesthesia. We observed 3 (5.6%) intraoperative seizures that required deepening of sedation.

CONCLUSION

AC using the monitored anesthesia care protocol was a safe and well-tolerated procedure with satisfactory patient experience. Extensive preoperative preparation should be considered a key part of the procedure.

Advanced frailty assessment tool predicts successful awake craniotomy in a 92-year-old patient: A case report

Background:

The awake craniotomy (AC) procedure allows for safe and maximal resection of brain tumors from highly eloquent regions. However, geriatric patients are often viewed as poor candidates for AC due to age and medical comorbidities. Frailty assessments gauge physiological reserve for surgery and are valuable tools for preoperative decision-making. Here, we present a novel case illustrating how frailty scoring enabled an elderly but otherwise healthy female to undergo successful AC for tumor resection.

Case Description:

A 92-year-old right-handed female with history of hypertension and basal cell skin cancer presented with a 1-month history of progressive aphasia and was found to have a ring-enhancing left frontoparietal mass abutting the rolandic cortex concerning for malignant neoplasm. Frailty scoring with the recalibrated risk analysis index (RAI-C) tool revealed a score of 30 (of 81) indicating low surgical risk. The patient and family were counseled appropriately that, despite advanced chronological age, a low frailty score predicts favorable surgical outcomes. The patient underwent left-sided AC for resection of tumor and experienced immediate improvement of speech intraoperatively. After surgery, the patient was neurologically intact and had an unremarkable postoperative course with significant improvements from preoperatively baseline at follow-up.

Conclusion:

To the best of our knowledge, this case represents the oldest patient to undergo successful AC for brain tumor resection. Nonfrail patients over 90 years of age with the proper indications may tolerate cranial surgery. Frailty scoring is a powerful tool for preoperative risk assessment in the geriatric neurosurgery population.

Rehabilitation Outcomes for Patients with Motor Deficits after Initial and Repeat Brain Tumor Surgery

Repeat surgery is often required to treat brain tumor recurrences. Here, we compared the functional state and rehabilitation of patients undergoing initial and repeat surgery for brain tumors to establish their individual risks that might impact management. In total, 835 patients underwent operations, and 139 (16.6%) required rehabilitation during the inpatient stay. The Karnofsky performance status, Barthel index, and the modified Rankin scale were used to assess functional status, and the gait index was used to assess gait efficiency. Motor skills, postoperative complications, and length of hospital stay were recorded. Patients were classified into two groups: first surgery (n = 103) and repeat surgery (n = 30). Eighteen percent of patients required reoperations, and these patients required prolonged postoperative rehabilitation as often as those operated on for the first time. Rehabilitation was more often complicated in the repeat surgery group (p = 0.047), and the complications were more severe and persistent. Reoperated patients had significantly worse motor function and independence in activities of daily living before surgery and at discharge, but the deterioration after surgery affected patients in the first surgery group to a greater extent according to all metrics (p < 0.001). The length of hospital stay was similar in both groups. These results will be useful for tailoring postoperative rehabilitation during a hospital stay on the neurosurgical ward as well as planning discharge requirements after leaving the hospital.

Role of resective surgery in patients older than 60 years with therapy-resistant epilepsy

OBJECTIVE

Epilepsy surgery for older adults is controversial owing to their longer duration of epilepsy and perceived higher surgical risk. However, because of an aging population and documented benefit of epilepsy surgery, surgery is considered more frequently for these patients. The authors' objective was to analyze the role of resective surgery in patients older than 60 years and to assess outcomes and safety.

METHODS

The authors conducted a retrospective analysis of 595 patients who underwent resective epilepsy surgery at their center from 1999 to 2018. Thirty-one patients aged 60 years or older were identified. Sixty patients younger than 60 years were randomly selected as controls. Population characteristics, results of presurgical evaluations, outcomes, and complications were analyzed.

RESULTS

No significant differences were found between the groups in terms of hemisphere dominance, side of surgery, presence of a lesion, and incidence of temporal lobe epilepsy. Epilepsy duration was greater in the older cohort (p = 0.019), and invasive EEG was more commonly employed in younger patients (p = 0.030). The rates of Engel class I outcome at 6 months, 1 year, and 2 years were 89.7%, 96.2%, and 94.7% for the older group and 75% (p = 0.159), 67.3% (p = 0.004), and 75.8% (p = 0.130) for the younger group, respectively. The proportion of seizure-free patients was greatest among those with temporal lobe epilepsy, particularly in the older group. Neurological complication rates did not differ significantly between groups, however medical and other minor complications occurred more frequently in the older group.

CONCLUSIONS

Patients older than 60 years had equal or better outcomes at 1 year after epilepsy surgery than younger patients. A trend toward a greater proportion of patients with lesional temporal lobe epilepsy was found in the older group. These results suggest that good seizure outcomes can be obtained in older patients despite longer duration of epilepsy.

Clinical and prognostic implications of rim restriction following glioma surgery

Rim restriction surrounding the resection cavity of glioma is often seen on immediate post-op diffusion-weighted imaging (DWI). The etiology and clinical impact of rim restriction are unknown. We evaluated the incidence, risk factors and clinical consequences of this finding. We evaluated patients that underwent surgery for low-grade glioma (LGG) and glioblastoma (GBM) without stroke on post-operative imaging. Analyses encompassed pre- and postoperative clinical, radiological, intraoperative monitoring, survival, functional and neurocognitive outcomes. Between 2013 and 2017, 63 LGG and 209 GBM patients (272 in total) underwent surgical resection and were included in our cohort. Post-op rim restriction was demonstrated in 68 patients, 32% (n = 20) of LGG and 23% (n = 48) of GBM patients. Risk factors for restriction included temporal tumors in GBM (p = 0.025) and insular tumors in LGG (p = 0.09), including longer surgery duration in LGG (p = 0.008). After a 1-year follow-up, LGG patients operated on their dominant with post-op restriction had a higher rate of speech deficits (46 vs 9%, p = 0.004). Rim restriction on postoperative imaging is associated with longer duration of glioma surgery and potentially linked to brain retraction. It apparently has no direct clinical consequences, but is linked to higher rates of speech deficits in LGG dominant-side surgeries.

Comparison of the Functional State and Motor Skills of Patients after Cerebral Hemisphere, Ventricular System, and Cerebellopontine Angle Tumor Surgery

Brain tumor location is an important factor determining the functional state after brain tumor surgery. We assessed the functional state and course of rehabilitation of patients undergoing surgery for brain tumors and assessed the location-dependent risk of loss of basic motor skills and the time needed for improvement after surgery. There were 835 patients who underwent operations, and 139 (16.6%) required rehabilitation during the inpatient stay. Karnofsky Performance Scale, Barthel Index, and the modified Rankin scale were used to assess functional status, whereas Gait Index was used to assess gait efficiency. Motor skills, overall length of stay (LOS) in hospital, and LOS after surgery were recorded. Patients were classified into four groups: cerebral hemisphere (CH), ventricular system (VS), and cerebellopontine angle (CPA) tumors; and a control group not requiring rehabilitation. VS tumor patients had the lowest scores in all domains compared with the other groups before surgery (p < 0.001). Their performance further deteriorated after surgery and by the day of discharge. They most often required long-lasting postoperative rehabilitation and had the longest LOS (35 days). Operation was most often required for CH tumors (77.7%), and all metrics and LOS parameters were better in these patients (p < 0.001). Patients with CPA tumors had the best outcomes (p < 0.001). Most patients (83.4%) with brain tumors did not require specialized rehabilitation, and LOS after surgery in the control group was on average 5.1 days after surgery. VS tumor patients represent a rehabilitation challenge. Postoperative rehabilitation planning must take the tumor site and preoperative condition into account.

The Efficacy of Intraoperative Passive Language Mapping for Glioma Surgery: A Case Report

Background: Recently, electrocorticographic (ECoG) studies have emphasized the importance of gamma band-based functional mapping in the presurgical localization of the eloquent cortex. Passive functional mapping using ECoG signals provides a reliable method for identifying receptive language areas without many of the risks and limitations associated with electrical cortical stimulation. We report a surgical case of left temporal malignant glioma with intraoperative passive language mapping. Case Description: A 78-year-old woman was diagnosed with left temporal glioma with inspection of her language difficulty. MRI showed a left temporal tumor measuring 74.6 × 50.0 × 51.5 mm in size. Real-time CortiQ-based mapping using high-gamma activity by word-listening and story-listening tasks was performed. Significant listening task-evoked high gamma activities were detected in 5 channels in the superior temporal gyrus and one channel in the middle temporal gyrus. The tumor was grossly removed except for the region corresponding to listening task-evoked high gamma activities. Postoperatively, the patient's symptoms of language comprehension difficulty improved, and no new neurological deficits were observed. Conclusion: Intraoperative passive language mapping was successfully performed, and the patient's language function was well-preserved. Intraoperative passive language mapping, which is applicable in a short time and under general anesthesia, can be an important tool for detecting language areas.

The Greek linguistic assessment for awake brain surgery: development process and normative data

Language mapping with direct electrical stimulation is considered the gold standard in surgical treatment of brain tumors. Assessing a variety of language functions intraoperatively can affect the extent of the tumor resection as well as the patient's postoperative quality of life. Although most tests include preoperative sessions where tasks are personalised to each patient, normative data are essential since they can ensure that the presented stimuli can be responded appropriately. In this study, we describe the development and standardisation procedures of the first linguistic test in Greek, designed specifically for brain mapping during awake craniotomies. The tasks are developed to comply with the special conditions and restrictions of language assessment inside the operating room. Each task is controlled for various psycholinguistic and lexical variables and it is associated with specific neuroanatomical areas and linguistic processes. Our population consists of 80 right-handed, healthy, Greek-speaking individuals aged 20-60 years. We found only a few main effects and interactions of demographic variables on our test scores. Most differences were found between age groups, since older participants tend to perform slightly worse than younger ones. Therefore, percentiles and cut-off scores were calculated separately for each demographic group. Regarding the clinical application of GLAABS, we describe the procedures we followed to administer it to brain tumor patients from our department and also discuss how sensitivity and specificity can affect patients' postoperative course.

The Use of Standardized Intraoperative Language Tests in Awake Craniotomies: A Scoping Review

Assessment of speech and language functions is an essential part of awake craniotomies. Although standardized and validated tests have several advantages compared to homemade (or mixed) batteries, in the literature it is unclear how such tests are used or whether they are used at all. In this study, we performed a scoping review in order to locate standardized and validated intraoperative language tests. Our inquiry included two databases (PubMED and MEDLINE), gray literature, and snowball referencing. We discovered 87 studies reporting use of mixed batteries, which consist of homemade tasks and tests borrowed from other settings. The tests we found to meet the validation and standardization criteria we set were ultimately three (n = 3) and each one has its own advantages and disadvantages. We argue that tests with high sensitivity and specificity not only can lead to better outcomes postoperatively, but they can also help us to gain a better understanding of the neuroanatomy of language.

Characteristic Alterations of Network in Patients With Intraoperative Stimulation-Induced Seizures During Awake Craniotomy

Background: The use of electrocorticography (ECoG) to avoid intraoperative stimulation-induced seizure (ISS) during awake craniotomy is controversial. Although a standard direct cortical stimulating (DCS) protocol is used to identify the eloquent cortices and subcortical structures, ISS still occurs. Epilepsy is related to alterations in brain networks. In this study, we investigated specific alterations in brain networks in patients with ISS. Methods: Twenty-seven patients with glioma were enrolled and categorized into the ISS and non-ISS groups based on their history of ISS occurrence. A standard DCS protocol was used during awake craniotomy without ECoG supervision. Graph theoretical measurement was used to analyze resting-state functional magnetic resonance imaging data to quantitatively reveal alterations in the functional networks. Results: In the sensorimotor networks, the glioma significantly decreased the functional connectivity (FC) of four edges in the ISS group, which were conversely increased in the non-ISS group after multiple corrections (p < 0.001, threshold of p-value = 0.002). Regarding the topological properties, the sensorimotor network of all participants was classified as a small-world network. Glioma significantly increased global efficiency, nodal efficiency, and the sigma value, as well as decreased the shortest path length in the ISS group compared with the non-ISS group (p < 0.05). Conclusions: The specific alterations indicating patient susceptibility to ISS during DCS increased global and nodal efficiencies and decreased the shortest path length and FC induced by gliomas. If the patient has these specific alterations, ECoG is recommended to monitor after-discharge current during DCS to avoid ISS.

High Grade Glioma Treatment in Elderly People: Is It Different Than in Younger Patients? Analysis of Surgical Management Guided by an Intraoperative Multimodal Approach and Its Impact on Clinical Outcome

OBJECTIVE

Age is considered a negative prognostic factor for High Grade Gliomas (HGGs) and many neurosurgeons remain skeptical about the benefits of aggressive treatment. New surgical and technological improvements may allow extended safe resection, with lower level of post-operative complications. This opportunity opens the unsolved question about the most appropriate HGG treatment in elderly patients. The aim of this study is to analyze if HGG maximal safe resection guided by an intraoperative multimodal imaging protocol coupled with neuromonitoring is associated with differences in outcome in elderly patients versus younger ones.

METHODS

We reviewed 100 patients, 53 (53%) males and 47 (47%) females, with median (IQR) age of 64 (57; 72) years. Eight patients were diagnosed with Anaplastic Astrocytoma (AA), 92 with Glioblastoma (GBM). Surgery was aimed to achieve safe maximal resection. An intraoperative multimodal imaging protocol, including neuronavigation, neurophysiological monitoring, 5-ALA fluorescence, 11C MET-PET, navigated i-US system and i-CT, was used, and its impact on EOTR and clinical outcome in elderly patients was analyzed. We divided patients in two groups according to their age: <65 and >65 years, and surgical and clinical results (EOTR, post-operative KPS, OS and PFS) were compared. Yet, to better understand age-related differences, the same patient cohort was also divided into <70 and >70 years and all the above data reanalyzed.

RESULTS

In the first cohort division, we did not found KPS difference over time and survival analysis did not show significant difference between the two groups (p = 0.36 for OS and p = 0.49 for PFS). Same results were obtained increasing the age cut-off for age up to 70 years (p = 0.52 for OS and p = 0.92 for PFS).

CONCLUSIONS

Our data demonstrate that there is not statistically significant difference in post-operative EOTR, KPS, OS, and PFS between younger and elderly patients treated with extensive tumor resection aided by a intraoperative multimodal protocol.

Endoscopic transsphenoidal surgery reduces the need for re-operation compared to the microscopic approach in pituitary macroadenomas

INTRODUCTION

Pituitary surgery has shifted in recent years from microscopic surgery(MS) to endoscopic endonasal surgery (EES). However, the comparative long-term outcome of these surgical approaches, including the need for subsequent re-operation has never been reported. We present our experience in a high-volume referral center experienced in both endoscopic and microscopic approaches to compare the need for re-operation after initial resection of non-functioning pituitary macroadenomas using these surgical approaches.

METHODS

684 patients (398 with NF adenomas) underwent trans-sphenoidal pituitary surgery in our institution between 2006 and 2017. Complete follow-up (mean 72 months, minimum two years) was available in 87 newly diagnosed patients with non-functioning pituitary macroadenomas (NFPMA; 48-microscopic and 39-endoscopic). The EES approach has been used almost exclusively since 2012. The need for repeat operation for tumor resection during the follow-up period was assessed as the primary end-point of the study. Extracted data included various demographic and clinical parameters, radiographic findings as well as the extent of resection (EOR).

RESULTS

The EOR was similar for both groups, with a trend towards better EOR in the EES group. The rate of surgical complications was also similar for both groups. There was a strong trend towards lower need for re-operation in the EES group compared to the MS group (12.8% vs. 29.2%, p = 0.056). In a multivariate analysis, only EOR and Knosp grade were independently associated with the need for re-operation surgery.

CONCLUSION

Our data indicate that EES in NFPMA tends to be associated with a lower need for re-operation compared to the MS approach, with a similar rate of EOR and complications.

Brain Metastases in Elderly Patients-The Role of Surgery in the Context of Systemic Treatment

In patients with brain metastases (BM), advanced age is considered a negative prognostic factor. To address the potential reasons for that, we assessed 807 patients who had undergone BM resection; 315 patients aged at least 65 years (group A) were compared with 492 younger patients (group B). We analyzed the impact of the pre- and postoperative Karnofsky performance status (KPS), postoperative treatment structure and post-treatment survival. BM resection significantly improved KPS scores in both groups (p = 0.0001). Median survival after BM resection differed significantly between the groups (A: 5.81 vs. B: 8.12 months; p = 0.0015). In both groups, patients who received postoperative systemic treatment showed significantly longer overall survival (p = 0.00001). However, elderly patients less frequently received systemic treatment (p = 0.0001) and the subgroup of elderly patients receiving such therapies had a significantly higher postsurgical KPS score (p = 0.0007). In all patients receiving systemic treatment, age was no longer a negative prognostic factor. Resection of BM improves the functional status of elderly patients, thus enhancing the likeliness to receive systemic treatment, which, in turn, leads to longer overall survival. In the context of such a treatment structure, age alone is no longer a prognostic factor for survival.

What effects does awake craniotomy have on functional and survival outcomes for glioblastoma patients?

PURPOSE

Neurosurgeons adopt several different surgical approaches to deal with glioblastomas (GB) located in or near eloquent areas. Some attempt maximal safe resection by awake craniotomy (AC), but doubts persist concerning the real benefits of this type of surgery in this situation. We performed a retrospective study to evaluate the extent of resection (EOR), functional and survival outcomes after AC of patients with GB in critical locations.

METHODS

Forty-six patients with primary GB treated with the Stupp regimen between 2004 and 2019, for whom brain mapping was feasible, were included. We assessed EOR, postoperative language and/or motor deficits three months after AC, progression-free survival (PFS) and overall survival (OS).

RESULTS

Complete resection was achieved in 61% of the 46 GB patients. The median PFS was 6.8 months (CI 6.1; 9.7) and the median OS was 17.6 months (CI 14.8; 34.1). Three months after AC, more than half the patients asymptomatic before surgery remained asymptomatic, and one third of patients with symptoms before surgery experienced improvements in language, but not motor functions. The risk of postoperative deficits was higher in patients with preoperative deficits or incomplete resection. Furthermore, the presence of postoperative deficits was an independent predictive factor for shorter PFS.

CONCLUSION

AC is an option for the resection of GB in critical locations. The observed survival outcomes are typical for GB patients in the Stupp era. However, the success of AC in terms of the recovery or preservation of language and/or motor functions cannot be guaranteed, given the aggressiveness of the tumor.

Incidence and impact of stroke following surgery for low-grade gliomas

OBJECTIVE

Ischemic complications are a common cause of neurological deficits following low-grade glioma (LGG) surgeries. In this study, the authors evaluated the incidence, risk factors, and long-term implications of intraoperative ischemic events.

METHODS

The authors retrospectively evaluated patients who had undergone resection of an LGG between 2013 and 2017. Analysis included pre- and postoperative demographic, clinical, radiological, and anesthetic data, as well as intraoperative neurophysiology data, overall survival, and functional and neurocognitive outcomes.

RESULTS

Among the 82 patients included in the study, postoperative diffusion-weighted imaging showed evidence of acute ischemic strokes in 19 patients (23%), 13 of whom (68%) developed new neurological deficits. Infarcts were more common in recurrent and insular surgeries (p < 0.05). Survival was similar between the patients with and without infarcts. Immediately after surgery, 27% of the patients without infarcts and 58% of those with infarcts experienced motor deficits (p = 0.024), decreasing to 16% (p = 0.082) and 37% (p = 0.024), respectively, at 1 year. Neurocognitive functions before and 3 months after surgery were generally stable for the two groups, with the exception of a decline in verbal rhyming ability among patients with infarcts. Confusion during awake craniotomy was a strong predictor of the occurrence of an ischemic stroke. Mean arterial pressure at the beginning of surgery was significantly lower in the infarct group.

CONCLUSIONS

Recurrent surgeries and insular tumor locations are risk factors for intraoperative strokes. Although they do not affect survival, these strokes negatively affect patient activity and performance status, mainly during the first 3 postoperative months, with gradual functional improvement over 1 year. Several intraoperative parameters may suggest the impending development of an infarct.

Focal Cortical Surface Cooling is a Novel and Safe Method for Intraoperative Functional Brain Mapping

OBJECTIVE

Electric cortical stimulation (ECS) has been the gold standard for intraoperative functional mapping in neurosurgery, yet it carries the risk of induced seizures. We assess the safety of focal cortical cooling (CC) as a potential alternative to ECS.

METHODS

We reviewed 40 patients (13 with tumor and 27 with mesial temporal lobe epilepsy) who underwent intraoperative CC at the University of Iowa Hospital and Clinics (CC group), of whom 38 underwent ECS preceding CC. Intraoperative and postoperative seizure incidence, postoperative neurologic deficits, and new postoperative radiographic findings were collected to assess CC safety. Fifty-five patients who underwent ECS mapping without CC (ECS-alone group) were reviewed as a control cohort. Another 25 patients who underwent anterior temporal lobectomy (ATL) without CC or ECS (no ECS/no CC-ATL group) were also reviewed to evaluate long-term effects of CC.

RESULTS

Seventy-nine brain sites in the CC group were cooled, comprising inferior frontal gyrus (44%), precentral gyrus (39%), postcentral gyrus (6%), subcentral gyrus (4%), and superior temporal gyrus (6%). The incidence of intraoperative seizure(s) was 0% (CC group) and 3.6% (ECS-alone group). The incidence of seizure(s) within the first postoperative week did not significantly differ among CC (7.9%), ECS-alone (9.0%), and no ECS/no CC-ATL groups (12%). There was no significant difference in the incidence of postoperative radiographic change between CC (7.5%) and ECS-alone groups (5.5%). Long-term seizure outcome (Engel I+II) for mesial temporal epilepsy did not differ among CC (80%), ECS-alone (83.3%), and no ECS/no CC-ATL groups (83.3%).

CONCLUSIONS

CC when used as an intraoperative mapping technique is safe and may complement ECS.

Awake craniotomy for resection of supratentorial glioblastoma: a systematic review and meta-analysis

Background

The goal of glioblastoma (GBM) surgery is to maximize the extent of resection (EOR) while minimizing postoperative neurological complications. Awake craniotomy (AC) has been demonstrated to achieve this goal for low-grade gliomas in or near eloquent areas. However, the efficacy of AC for GBM resection has not been established. Therefore, we aimed to investigate the outcomes of AC for surgical resection of GBM using a systematic review and meta-analysis of published studies.

Methods

Systematic searches of Ovid MEDLINE, Embase, Cochrane Controlled Register of Controlled Trials, and PubMed were performed from database inception to September 14, 2019 for published studies reporting outcomes of AC for GBM resection. Outcome measures analyzed included EOR and the event rate of postoperative neurological deficits.

Results

A total of 1928 unique studies were identified. Fourteen studies reporting 278 patients were included in our meta-analysis. Mean age of patients was 46.9 years (95% confidence interval [CI]: 43.9–49.9). Early and late postoperative neurological deficits occurred in 34.5% (95% CI: 21.9–48.2) and 1.9% (95% CI: 0.0–9.2) of patients, respectively. Pooled percentage of gross total resection (GTR) was 74.7% (95% CI: 66.7–82.1), while the pooled percentage reduction in tumor volume was 95.3% (95% CI: 92.2–98.4).

Conclusions

Limited current evidence suggests that the use of AC for resection of supratentorial GBM is associated with a low rate of persistent neurological deficits while achieving an acceptable rate of GTR. Our findings demonstrate the potential viability of AC in GBM resection and highlight the need for further research on this topic.

Using cortical function mapping by awake craniotomy dealing with the patient with recurrent glioma in the eloquent cortex

Background

Methods

Results

Conclusion

Comparison of Motor Outcome in Patients Undergoing Awake vs General Anesthesia Surgery for Brain Tumors Located Within or Adjacent to the Motor Pathways

BACKGROUND

Surgical removal of intra-axial brain tumors aims at maximal tumor resection while preserving function. The potential benefit of awake craniotomy over craniotomy under general anesthesia (GA) for motor preservation is yet unknown.

OBJECTIVE

To compare the clinical outcomes of patients who underwent surgery for perirolandic tumors while either awake or under GA.

METHODS

Between 2004 and 2015, 1126 patients underwent surgical resection of newly diagnosed intra-axial tumors in a single institution. Data from 85 patients (44 awake, 41 GA) with full dataset who underwent resections for perirolandic tumors were retrospectively analyzed.

RESULTS

Identification of the motor cortex required significantly higher stimulation thresholds in anesthetized patients (9.1 ± 4 vs 6.2 ± 2.7 mA for awake patients, P = .0008). There was no group difference in the subcortical threshold for motor response used to assess the proximity of the lesion to the corticospinal (pyramidal) tract. High-grade gliomas were the most commonly treated pathology. The extent of resection and residual tumor volume were not different between groups. Postoperative motor deficits were more common in the anesthetized patients at 1 wk (P = .046), but no difference between the groups was detected at 3 mo. Patients in the GA group had a longer mean length of hospitalization (10.3 vs 6.7 d for the awake group, P = .003).

CONCLUSION

Awake craniotomy results in a better early postoperative motor outcome and shorter hospitalization compared with patients who underwent the same surgery under GA. The finding of higher cortical thresholds for the identification of the motor cortex in anesthetized patients may suggest an inhibitory effect of anesthetic agents on motor function.

Brain Tumor Surgery is Safe in Octogenarians and Nonagenarians: A Single-Surgeon 741 Patient Series

OBJECTIVES

Elderly patients with surgically accessible brain tumors are often not offered clinically indicated brain tumor surgery (BTS) because of to assumptions of greater risk for perioperative morbidity and mortality. Because brain tumor incidence is highest in the geriatric population, and because the global population is aging, accurate understanding of BTS risk in elderly patients is critical. We aimed to compare safety of BTS in elderly patients with younger counterparts to better understand the risk-benefit profile of BTS for elderly patients.

METHODS

Retrospective cohort study of young (20-29 years), senior (60-79 years), and elderly (80+ years) patients who underwent BTS with a single neurosurgeon. Differences between pre- and postoperative modified Rankin score (ΔmRS), length of hospitalization (LOH), complication rate, and 30-day readmission rates (30DRR) were recorded.

RESULTS

A total of 741 patients (83 elderly, 570 senior, and 88 young) were identified. No significant difference in preoperative mRS between different age groups, χ² = 0.269, P = 0.874. Elderly complication rate was 6.0%, not significantly different from young (4.5%, P = 0.667) or senior (7.2%, P = 0.696) complication rate. Elderly LOH was 1.93 ± SD 0.176 days; not significantly different from young (3.01 ± 0.384 days, P = 0.081) or senior (2.47 ± 0.144 days, P = 0.881). Statistical equivalence testing showed with 95% confidence that there was equivalence in ΔmRS among age groups.

CONCLUSIONS

Elderly patients did not have significantly different ΔmRS, LOH, 30DRR, or complication rates after BTS compared with younger counterparts. Therefore, in healthy patients, advanced age alone should not prevent patients from being offered BTS.

Conscious Experience and Psychological Consequences of Awake Craniotomy

BACKGROUND

Experiencing cranial surgery under awake conditions may expose patients to considerable psychological strain.

METHODS

This study aimed to investigate the occurrence and course of psychological sequelae following awake craniotomy (AC) for brain tumors in a series of 20 patients using a broad, validated psychological assessment preoperatively, intraoperatively, postoperatively and a standardized follow-up of 3 months. In addition, the association of the preoperative psychological condition (including, but not limited to, anxiety and fear) with perioperative pain perception and interference was assessed.

RESULTS

AC did not induce any shift in the median levels of anxiety, depression, and stress symptoms already present prior to the procedure. Furthermore, anxiety and depression were all moderately to strongly associated over time (all P < 0.05). Stress symptoms also correlated positively over all times of measurement. Stress 3 days after surgery was strongly associated with stress 3 months after surgery (P < 0.001), whereas the correlation between preoperative and immediate postoperative stress showed a statistical trend (P = 0.07). Preoperative fear was not related to intraoperative pain, but to pain and its interference with daily activity on the third postoperative day (P < 0.001 and P < 0.01, respectively).

CONCLUSIONS

Postoperative psychological symptoms clearly correlated with their corresponding preoperative symptoms. Thus, mental health was not negatively affected by the AC experience in our series. Intraoperative fear and pain were not related to the preoperative psychological condition. However, preoperative fear and anxiety were positively related with pain and its interference with daily activity in the immediate postoperative period.

An Awake Throughout Approach for Awake Craniotomy: A Perspective from a Resource-Limited Country

BACKGROUND

An awake throughout (AT) approach for awake craniotomy is mostly under utilized. The purpose of this study was to review the efficacy of the technique at our tertiary care center. The primary objective was to identify the incidence of perioperative complications. The secondary objective was to review the patients' satisfaction, satisfaction of surgical team, length of stay (LOS) in special care unit (SCU), and overall LOS in the hospital.

METHODS

The study was a retrospective review of patients data. All patients were treated with the AT technique. This included preoperative assessment, psychologic preparation, and institution of scalp block. The incidence of perioperative complications, including satisfaction of surgical team was noted. The patients' satisfaction and the LOS in SCU and in the hospital was also recorded.

RESULTS

In total, the data from 55 patients were reviewed. Their mean age was 41 years, and 63% were reported to have seizures at presentation. The AT approach was successful in 100% of cases. The incidence of intraoperative seizures was 7.4%, of vomiting was 5.4%, and of conversion to general anesthesia was 0%. The surgical team was able to perform gross total resection in 53% of patients and rated a satisfaction score of 8 out of 10. Postoperative seizures occurred in 5.4% of patients and vomiting in 3.6%. The mean LOS in SCU was 1.2 days, and the overall hospital LOS was 4 days. The patients remained fully satisfied, as evidenced by a mean satisfaction score of 8.6.

CONCLUSION

An AT approach might be very useful in resource-limited setups because of the low incidence of complications, the use of resources, and significant surgeon and patient satisfaction.

Improvement in cognitive function after surgery for low-grade glioma

OBJECTIVE

Cognition is a key component in health-related quality of life (HRQoL) and is currently incorporated as a major parameter of outcome assessment in patients treated for brain tumors. The effect of surgery on cognition and HRQoL remains debatable. The authors investigated the impact of resection of low-grade gliomas (LGGs) on cognition and the correlation with various histopathological markers.

METHODS

A retrospective analysis of patients with LGG who underwent craniotomy for tumor resection at a single institution between 2010 and 2014 was conducted. Of 192 who underwent resective surgery for LGG during this period, 49 had complete pre- and postoperative neurocognitive evaluations and were included in the analysis. These patients completed a full battery of neurocognitive tests (memory, language, attention and working memory, visuomotor organization, and executive functions) pre- and postoperatively. Tumor and surgical characteristics were analyzed, including volumetric measurements and histopathological markers (IDH, p53, GFAP).

RESULTS

Postoperatively, significant improvement was found in memory and executive functions. A subgroup analysis of patients with dominant-side tumors, most of whom underwent intraoperative awake mapping, revealed significant improvement in the same domains. Patients whose tumors were on the nondominant side displayed significant improvement only in memory functions. Positive staining for p53 testing was associated with improved language function and greater extent of resection in dominant-side tumors. GFAP positivity was associated with improved memory in patients whose tumors were on the nondominant side. No correlation was found between cognitive outcome and preoperative tumor volume, residual volume, extent of resection, or IDH1 status.

CONCLUSIONS

Resection of LGG significantly improves memory and executive function and thus is likely to improve functional outcome in addition to providing oncological benefit. GFAP and pP53 positivity could possibly be associated with improved cognitive outcome. These data support early, aggressive, surgical treatment of LGG.

Awake craniotomy in glioma surgery: is it necessary?

INTRODUCTION

The awake craniotomy has evolved from its humble beginnings in ancient cultures to become one of the most eloquent modern neurosurgical procedures. The development of intraoperative mapping techniques like direct electrostimulation of the cortex and subcortical white matter have further argued for its place in the neurosurgeon's armamentarium. Yet the suitability of the awake craniotomy with intraoperative functional mapping (ACWM) to optimize oncofunctional balance after peri-eloquent glioma resection continues to be a topic of active investigation as new methods of intraoperative monitoring and some unfavorable outcome data question its necessity.

EVIDENCE ACQUISITION

The neurosurgery and anesthesiology literatures were scoured for English-language studies that analyzed or reviewed the ACWM or its components as applied to glioma surgery via the PubMed, ClinicalKey, and OvidMEDLINE® databases or via direct online searches of journal archives.

EVIDENCE SYNTHESIS

Information on background, conceptualization, standard techniques, and outcomes of the ACWM were provided and compared. We parceled the procedure into its components and qualitatively described positive and negative outcome data for each. Findings were presented in the context of each study without attempt at quantitative analysis or reconciliation of heterogeneity between studies. Certain illustrative studies were highlighted throughout the review. Overarching conclusions were drawn based on level of evidence, expert opinion, and predominate concordance of data across studies in the literature.

CONCLUSIONS

Most investigators and studies agree that the ACWM is the best currently available approach to optimize oncofunctional balance in this difficult-to-treat patient population. This qualitative review synthesizes the most currently available data on the topic to provide contemporaneous insight into how and why the ACWM has become a favorite operation of neurosurgeons worldwide for the resection of gliomas from eloquent brain.

Awake Craniotomy vs Craniotomy Under General Anesthesia for Perirolandic Gliomas: Evaluating Perioperative Complications and Extent of Resection

BACKGROUND

A craniotomy with direct cortical/subcortical stimulation either awake or under general anesthesia (GA) present 2 approaches for removing eloquent region tumors. With a reported higher prevalence of intraoperative seizures occurring during awake resections of perirolandic lesions, oftentimes, surgery under GA is chosen for these lesions.

OBJECTIVE

To evaluate a single-surgeon's experience with awake craniotomies (AC) vs surgery under GA for resecting perirolandic, eloquent, motor-region gliomas.

METHODS

Between 2005 and 2015, a retrospective analysis of 27 patients with perirolandic, eloquent, motor-area gliomas that underwent an AC were case-control matched with 31 patients who underwent surgery under GA for gliomas in the same location. All patients underwent direct brain stimulation with neuromonitoring and perioperative risk factors, extent of resection, complications, and discharge status were assessed.

RESULTS

The postoperative Karnofsky Performance Score (KPS) was significantly lower for the GA patients at 81.1 compared to the AC patients at 93.3 ( P = .040). The extent of resection for GA patients was 79.6% while the AC patients had an 86.3% resection ( P = .136). There were significantly more 100% total resections in the AC patients 25.9% compared to the GA group (6.5%; P = .041). Patients in the GA group had a longer mean length of hospitalization of 7.9 days compared to the AC group at 4.2 days ( P = .049).

CONCLUSION

We show that AC can be performed with more frequent total resections, better postoperative KPS, shorter hospitalizations, as well as similar perioperative complication rates compared to surgery under GA for perirolandic, eloquent motor-region glioma.

Prognosis of older patients with low-grade glioma: A retrospective study

Introduction

Clinical behavior, treatment parameters, and prognostic factors are less well defined in older adults with low-grade gliomas (LGG). We conducted a two-institution retrospective review of older patients with LGG to better understand disease characteristics and prognosis in this population.

Methods

Northwestern University (NU) and The University of Washington (UW) clinical research databases were queried for patients ≥ 50 years of age with a diagnosis of WHO grade II glioma between January 1, 2000 and December 2012 (UW). Medical records were reviewed and data relevant to diagnosis, treatment and outcomes were collected. PFS and OS with respect to prognostic factors were calculated. Log-rank test and multivariate proportional hazards models were calculated for multiple tumor characteristics.

Results

Thirty-five patients with a diagnosis of LGG (WHO grade II) were identified; 15 women and 20 men had a median age of 55 (range 50-78). Fourteen had astrocytomas, fourteen had oligodendrogliomas and seven had oligoastrocytomas. Eight patients had contrast enhancement on neuroimaging, 9 of 21 tested had 1p19q co-deletion and 5 of 14 tested had an IDH1 mutation. Five year PFS was 21% with median PFS of 17 months; 20 patients had died (5 year OS=43%, median OS=48 months). On univariate analysis There was a statistically significant improvement in OS for patients with mixed histology (p=0.001), no midline shift at diagnosis (p=0.002) and with IDH1 mutation (p=0.003).

Conclusion

LGG appear more aggressive in older patients. Treatment following surgical resection should be considered; ongoing studies may clarify the most appropriate treatments for this age group.

Brain tumors in eloquent areas: A European multicenter survey of intraoperative mapping techniques, intraoperative seizures occurrence, and antiepileptic drug prophylaxis

Intraoperative mapping and monitoring techniques for eloquent area tumors are routinely used world wide. Very few data are available regarding mapping and monitoring methods and preferences, intraoperative seizures occurrence and perioperative antiepileptic drug management. A questionnaire was sent to 20 European centers with experience in intraoperative mapping or neurophysiological monitoring for the treatment of eloquent area tumors. Fifteen centers returned the completed questionnaires. Data was available on 2098 patients. 863 patients (41.1%) were operated on through awake surgery and intraoperative mapping, while 1235 patients (58.8%) received asleep surgery and intraoperative electrophysiological monitoring or mapping. There was great heterogeneity between centers with some totally AW oriented (up to 100%) and other almost totally ASL oriented (up to 92%) (31% SD). For awake surgery, 79.9% centers preferred an asleep-awake-asleep anesthesia protocol. Only 53.3% of the centers used ECoG or transcutaneous EEG. The incidence of intraoperative seizures varied significantly between centers, ranging from 2.5% to 54% (p < 0.001). It there appears to be a statistically significant link between the mastery of mapping technique and the risk of intraoperative seizures. Moreover, history of preoperative seizures can significantly increase the risk of intraoperative seizures (p < 0.001). Intraoperative seizures occurrence was similar in patients with or without perioperative drugs (12% vs. 12%, p = 0.2). This is the first European survey to assess intraoperative functional mapping and monitoring protocols and the management of peri- and intraoperative seizures. This data can help identify specific aspects that need to be investigated in prospective and controlled studies.

Anaesthesia Management for Awake Craniotomy: Systematic Review and Meta-Analysis

BACKGROUND

Awake craniotomy (AC) renders an expanded role in functional neurosurgery. Yet, evidence for optimal anaesthesia management remains limited. We aimed to summarise the latest clinical evidence of AC anaesthesia management and explore the relationship of AC failures on the used anaesthesia techniques.

METHODS

Two authors performed independently a systematic search of English articles in PubMed and EMBASE database 1/2007-12/2015. Search included randomised controlled trials (RCTs), observational trials, and case reports (n>4 cases), which reported anaesthetic approach for AC and at least one of our pre-specified outcomes: intraoperative seizures, hypoxia, arterial hypertension, nausea and vomiting, neurological dysfunction, conversion into general anaesthesia and failure of AC. Random effects meta-analysis was used to estimate event rates for four outcomes. Relationship with anaesthesia technique was explored using logistic meta-regression, calculating the odds ratios (OR) and 95% confidence intervals [95%CI].

RESULTS

We have included forty-seven studies. Eighteen reported asleep-awake-asleep technique (SAS), twenty-seven monitored anaesthesia care (MAC), one reported both and one used the awake-awake-awake technique (AAA). Proportions of AC failures, intraoperative seizures, new neurological dysfunction and conversion into general anaesthesia (GA) were 2% [95%CI:1-3], 8% [95%CI:6-11], 17% [95%CI:12-23] and 2% [95%CI:2-3], respectively. Meta-regression of SAS and MAC technique did not reveal any relevant differences between outcomes explained by the technique, except for conversion into GA. Estimated OR comparing SAS to MAC for AC failures was 0.98 [95%CI:0.36-2.69], 1.01 [95%CI:0.52-1.88] for seizures, 1.66 [95%CI:1.35-3.70] for new neurological dysfunction and 2.17 [95%CI:1.22-3.85] for conversion into GA. The latter result has to be interpreted cautiously. It is based on one retrospective high-risk of bias study and significance was abolished in a sensitivity analysis of only prospectively conducted studies.

CONCLUSION

SAS and MAC techniques were feasible and safe, whereas data for AAA technique are limited. Large RCTs are required to prove superiority of one anaesthetic regime for AC.

Continuous physical examination during subcortical resection in awake craniotomy patients: Its usefulness and surgical outcome

OBJECTIVES

To evaluate the value of physical examination as a monitoring tool during subcortical resection in awake craniotomy patients and surgical outcomes.

PATIENTS AND METHODS

Authors reviewed medical records of patients underwent awake craniotomy with continuous physical examination for pathology adjacent to the eloquent area.

RESULTS

Between January 2006 and August 2015, there were 37 patients underwent awake craniotomy with continuous physical examination. Pathology was located in the left cerebral hemisphere in 28 patients (75.7%). Thirty patients (81.1%) had neuroepithelial tumors. Degree of resections were defined as total, subtotal, and partial in 16 (43.2%), 11 (29.7%) and 10 (27.0%) patients, respectively. Median follow up duration was 14 months. The reasons for termination of subcortical resection were divided into 3 groups as follows: 1) by anatomical landmark with the aid of neuronavigation in 20 patients (54%), 2) by reaching subcortical stimulation threshold in 8 patients (21.6%), and 3) by abnormal physical examination in 9 patients (24.3%). Among these 3 groups, there were statistically significant differences in the intraoperative (p=0.002) and early postoperative neurological deficit (p=0.005) with the lowest deficit in neuronavigation group. However, there were no differences in neurological outcome at later follow up (3-months p=0.103; 6-months p=0.285). There were no differences in the degree of resection among the groups.

CONCLUSION

Continuous physical examination has shown to be of value as an additional layer of monitoring of subcortical white matter during resection and combining several methods may help increase the efficacy of mapping and monitoring of subcortical functions.

Awake craniotomy to maximize glioma resection: methods and technical nuances over a 27-year period

OBJECT

Awake craniotomy is currently a useful surgical approach to help identify and preserve functional areas during cortical and subcortical tumor resections. Methodologies have evolved over time to maximize patient safety and minimize morbidity using this technique. The goal of this study is to analyze a single surgeon's experience and the evolving methodology of awake language and sensorimotor mapping for glioma surgery.

METHODS

The authors retrospectively studied patients undergoing awake brain tumor surgery between 1986 and 2014. Operations for the initial 248 patients (1986–1997) were completed at the University of Washington, and the subsequent surgeries in 611 patients (1997–2014) were completed at the University of California, San Francisco. Perioperative risk factors and complications were assessed using the latter 611 cases.

RESULTS

The median patient age was 42 years (range 13–84 years). Sixty percent of patients had Karnofsky Performance Status (KPS) scores of 90–100, and 40% had KPS scores less than 80. Fifty-five percent of patients underwent surgery for high-grade gliomas, 42% for low-grade gliomas, 1% for metastatic lesions, and 2% for other lesions (cortical dysplasia, encephalitis, necrosis, abscess, and hemangioma). The majority of patients were in American Society of Anesthesiologists (ASA) Class 1 or 2 (mild systemic disease); however, patients with severe systemic disease were not excluded from awake brain tumor surgery and represented 15% of study participants. Laryngeal mask airway was used in 8 patients (1%) and was most commonly used for large vascular tumors with more than 2 cm of mass effect. The most common sedation regimen was propofol plus remifentanil (54%); however, 42% of patients required an adjustment to the initial sedation regimen before skin incision due to patient intolerance. Mannitol was used in 54% of cases. Twelve percent of patients were active smokers at the time of surgery, which did not impact completion of the intraoperative mapping procedure. Stimulation-induced seizures occurred in 3% of patients and were rapidly terminated with ice-cold Ringer's solution. Preoperative seizure history and tumor location were associated with an increased incidence of stimulation-induced seizures. Mapping was aborted in 3 cases (0.5%) due to intraoperative seizures (2 cases) and patient emotional intolerance (1 case). The overall perioperative complication rate was 10%.

CONCLUSIONS

Based on the current best practice described here and developed from multiple regimens used over a 27-year period, it is concluded that awake brain tumor surgery can be safely performed with extremely low complication and failure rates regardless of ASA classification; body mass index; smoking status; psychiatric or emotional history; seizure frequency and duration; and tumor site, size, and pathology.

Tumor location and IDH1 mutation may predict intraoperative seizures during awake craniotomy

OBJECT

Intraoperative seizures during awake craniotomy may interfere with patients' ability to cooperate throughout the procedure, and it may affect their outcome. The authors have assessed the occurrence of intraoperative seizures during awake craniotomy in regard to tumor location and the isocitrate dehydrogenase 1 (IDH1) status of the tumor.

METHODS

Data were collected in 137 consecutive patients who underwent awake craniotomy for removal of a brain tumor. The authors performed a retrospective analysis of the incidence of seizures based on the tumor location and its IDH1 mutation status, and then compared the groups for clinical variables and surgical outcome parameters.

RESULTS

Tumor location was strongly associated with the occurrence of intraoperative seizures. Eleven patients (73%) with tumor located in the supplementary motor area (SMA) experienced intraoperative seizures, compared with 17 (13.9%) with tumors in the other three non-SMA brain regions (p < 0.0001). Interestingly, there was no significant association between history of seizures and tumor location (p = 0.44). Most of the patients (63.6%) with tumor in the SMA region harbored an IDH1 mutation compared with those who had tumors in non-SMA regions. Thirty-one of 52 patients (60%) with a preoperative history of seizures had an IDH1 mutation (p = 0.02), and 15 of 22 patients (68.2%) who experienced intraoperative seizures had an IDH1 mutation (p = 0.03). In a multivariate analysis, tumor location was found as a significant predictor of intraoperative seizures (p = 0.002), and a trend toward IDH1 mutation as such a predictor was found as well (p = 0.06). Intraoperative seizures were not associated with worse outcome.

CONCLUSIONS

Patients with tumors located in the SMA are more prone to develop intraoperative seizures during awake craniotomy compared with patients who have a tumor in non-SMA frontal areas and other brain regions. The IDH1 mutation was more common in SMA region tumors compared with other brain regions, and may be an additional risk factor for the occurrence of intraoperative seizures.

Patient response to awake craniotomy - a summary overview

BACKGROUND

Awake craniotomy is a valuable procedure since it allows brain mapping and live monitoring of eloquent brain functions. The advantage of minimizing resource utilization is also emphasized by some physicians in North America. Data on how well an awake craniotomy is tolerated by patients and how much stress it creates is available from different studies, but this topic has not consequently been summarized in a review of the available literature. Therefore, it is the purpose of this review to shed more light on the still controversially discussed aspect of an awake craniotomy.

METHODS

We reviewed the available English literature published until December 2013 searching for studies that investigated patients' responses to awake craniotomies.

RESULTS

Twelve studies, published between 1998 and 2013, including 396 patients with awake surgery were identified. Eleven of these 12 studies set the focus on the perioperative time, one study focused on the later postoperative time. The vast majority of patients felt well prepared and overall satisfaction with the procedure was high. In the majority of studies up to 30 % of the patients recalled considerable pain and 10-14 % experienced strong anxiety during the procedure. The majority of patients reported that they would undergo an awake craniotomy again. A post traumatic stress disorder was present neither shortly nor years after surgery. However, a normal human response to such an exceptional situation can for instance be the delayed appearance of unintentional distressing recollections of the event despite the patients' satisfaction concerning the procedure.

CONCLUSIONS

For selected patients, an awake craniotomy presents the best possible way to reduce the risk of surgery related neurological deficits. However, benefits and burdens of this type of procedure should be carefully considered when planning an awake craniotomy and the decision should serve the interests of the patient.