Augmented reality head-mounted display–based incision planning in cranial neurosurgery: a prospective pilot study

OBJECTIVE Monitor and wand–based neuronavigation stations (MWBNSs) for frameless intraoperative neuronavigation are routinely used in cranial neurosurgery. However, they are temporally and spatially cumbersome; the OR must be arranged around the MWBNS, at least one hand must be used to manipulate the MWBNS wand (interrupting a bimanual surgical technique), and the surgical workflow is interrupted as the surgeon stops to “check the navigation” on a remote monitor. Thus, there is need for continuous, real-time, hands-free, neuronavigation solutions. Augmented reality (AR) is poised to streamline these issues. The authors present the first reported prospective pilot study investigating the feasibility of using the OpenSight application with an AR head-mounted display to map out the borders of tumors in patients undergoing elective craniotomy for tumor resection, and to compare the degree of correspondence with MWBNS tracing. METHODS Eleven consecutive patients undergoing elective craniotomy for brain tumor resection were prospectively identified and underwent circumferential tumor border tracing at the time of incision planning by a surgeon wearing HoloLens AR glasses running the commercially available OpenSight application registered to the patient and preoperative MRI. Then, the same patient underwent circumferential tumor border tracing using the StealthStation S8 MWBNS. Postoperatively, both tumor border tracings were compared by two blinded board-certified neurosurgeons and rated as having an excellent, adequate, or poor correspondence degree based on a subjective sense of the overlap. Objective overlap area measurements were also determined. RESULTS Eleven patients undergoing craniotomy were included in the study. Five patient procedures were rated as having an excellent correspondence degree, 5 had an adequate correspondence degree, and 1 had poor correspondence. Both raters agreed on the rating in all cases. AR tracing was possible in all cases. CONCLUSIONS In this small pilot study, the authors found that AR was implementable in the workflow of a neurosurgery OR, and was a feasible method of preoperative tumor border identification for incision planning. Future studies are needed to identify strategies to improve and optimize AR accuracy.

Reducing Superfluous Opioid Prescribing Practices After Brain Surgery: It Is Time to Talk About Drugs

BACKGROUND Opioids are prescribed routinely after cranial surgery despite a paucity of evidence regarding the optimal quantity needed. Overprescribing may adversely contribute to opioid abuse, chronic use, and diversion. OBJECTIVE To evaluate the effectiveness of a system-wide campaign to reduce opioid prescribing excess while maintaining adequate analgesia. METHODS A retrospective cohort study of patients undergoing a craniotomy for tumor resection with home disposition before and after a 2-mo educational intervention was completed. The educational initiative was composed of directed didactic seminars targeting senior staff, residents, and advanced practice providers. Opioid prescribing patterns were then assessed for patients discharged before and after the intervention period. RESULTS A total of 203 patients were discharged home following a craniotomy for tumor resection during the study period: 98 who underwent surgery prior to the educational interventions compared to 105 patients treated post-intervention. Following a 2-mo educational period, the quantity of opioids prescribed decreased by 52% (median morphine milligram equivalent per day [interquartile range], 32.1 [16.1, 64.3] vs 15.4 [0, 32.9], P < .001). Refill requests also decreased by 56% (17% vs 8%, P = .027) despite both groups having similar baseline characteristics. There was no increase in pain scores at outpatient follow-up (1.23 vs 0.85, P = .105). CONCLUSION A dramatic reduction in opioids prescribed was achieved without affecting refill requests, patient satisfaction, or perceived analgesia. The use of targeted didactic education to safely improve opioid prescribing following intracranial surgery uniquely highlights the ability of simple, evidence-based interventions to impact clinical decision making, lessen potential patient harm, and address national public health concerns.

Middle Frontal Gyrus and Area 55b: Perioperative Mapping and Language Outcomes

Background: The simplistic approaches to language circuits are continuously challenged by new findings in brain structure and connectivity. The posterior middle frontal gyrus and area 55b (pFMG/area55b), in particular, has gained a renewed interest in the overall language network.Methods: This is a retrospective single-center cohort study of patients who have undergone awake craniotomy for tumor resection. Navigated transcranial magnetic simulation (nTMS), tractography, and intraoperative findings were correlated with language outcomes.Results: Sixty-five awake craniotomies were performed between 2012 and 2020, and 24 patients were included. nTMS elicited 42 positive responses, 76.2% in the inferior frontal gyrus (IFG), and hesitation was the most common error (71.4%). In the pMFG/area55b, there were seven positive errors (five hesitations and two phonemic errors). This area had the highest positive predictive value (43.0%), negative predictive value (98.3%), sensitivity (50.0%), and specificity (99.0%) among all the frontal gyri. Intraoperatively, there were 33 cortical positive responses—two (6.0%) in the superior frontal gyrus (SFG), 15 (45.5%) in the MFG, and 16 (48.5%) in the IFG. A total of 29 subcortical positive responses were elicited−21 in the deep IFG–MFG gyri and eight in the deep SFG–MFG gyri. The most common errors identified were speech arrest at the cortical level (20 responses−13 in the IFG and seven in the MFG) and anomia at the subcortical level (nine patients—eight in the deep IFG–MFG and one in the deep MFG–SFG). Moreover, 83.3% of patients had a transitory deterioration of language after surgery, mainly in the expressive component (p = 0.03). An increased number of gyri with intraoperative positive responses were related with better preoperative (p = 0.037) and worse postoperative (p = 0.029) outcomes. The involvement of the SFG–MFG subcortical area was related with worse language outcomes (p = 0.037). Positive nTMS mapping in the IFG was associated with a better preoperative language outcome (p = 0.017), relating to a better performance in the expressive component, while positive mapping in the MFG was related to a worse preoperative receptive component of language (p = 0.031).Conclusion: This case series suggests that the posterior middle frontal gyrus, including area 55b, is an important integration cortical hub for both dorsal and ventral streams of language.

Impact of 1p/19q Codeletion Status in The Outcome of Patients Affected By Oligodendroglioma and Diffuse Astrocytoma: A Retrospective Single Surgeon Series With 1.5 Io-MRI Guided Surgery

Purpose: The real impact of the Extent of Resection in respect to the 1p/19q codeletion status in determining the outcomes of Low Grade Glioma (LGG) patients is extensively debated. The aim of this paper is to retrospectively analyze the oncologic outcomes of a homogeneous cohort of LGG patients who underwent surgery by a single operator, first author of the present paper (GDA).Methods: A total of 66 patients suffering LGG who underwent craniotomy for tumor resection were operated on and retrospectively evaluated between 2008 and 2016 in a single center in which the operative theater was equipped with an Io-MRI system. We compared a subgroup of 37 patients suffering from Diffuse Astrocytoma to a second subgroup of 29 patients affected by Oligodendroglioma. Volumetric analyses of the Extent of Resection (EOR) were performed, PFS and OS were accurately recorded and used as endpoint variable, as well as the 1p/19q codeletion status of every patient included in the final cohort.Results: GTR produced a statistically significant survival advantage in respect to those associated with STR. This finding is confirmed even in patients suffering from Oligodendrogliomas (in the 1p/19q codeletion group 73.27 versus 101.73 months p=.0001). Similar findings were confimed for patients affected by Diffuse Astrocytomas(81.63 versus 60.44 months p < 0.012), despite the globally shorter survival.Conclusions: We can affirm that the EOR is an independent predictor of survival advantage. The 1p/19q codeletion is an independent prognostic factor significantly associated to a globally longer survival and a longer time to malignant transformation.

Navigated transcranial magnetic stimulation following awake craniotomy for resection of glioma: Description of two cases

Background: Although transcranial magnetic stimulation (TMS) has been indicated as a potential therapy for several neurologic conditions, there is little known regarding its use during the postoperative rehabilitation period in patients with brain tumors. Furthermore, seizures, a common presentation in these patients, are regarded as a major contraindication for TMS therapy. Case Description: We demonstrate that postoperative continuous theta burst stimulation (cTBS), a patterned form of repetitive TMS, was safely tolerated in addition to current neurorehabilitation techniques in two brain tumor patients, including one patient with a history of tumor-related epilepsy. We administered navigated 5 Hz cTBS to two patients within 48 h following awake craniotomy for tumor resection. Active motor thresholds were measured in both patients before TBS administration to determine stimulus intensity. We used resting-state fMRI to identify likely damaged networks based on postoperative deficits. This aided in TMS planning and allowed deficit targeted therapy contralateral to the lesioned network node. Both patients tolerated TBS therapy well and had no adverse effects, including posttreatment seizures, despite one patient having a history of tumor-related epilepsy. Conclusion: TBS may be safe in the immediate postoperative period for patients following brain tumor resection. Additional studies are needed to quantify the efficacy of TMS in improving neurologic deficits following tumor resection.

Increased complication and mortality among non-index hospital readmissions after brain tumor resection is associated with low-volume readmitting hospitals

OBJECTIVEFragmentation of care following craniotomy for tumor resection is increasingly common with the regionalization of neurosurgery. Hospital readmission to a hospital (non-index) other than the one from which patients received their original care (index) has been associated with increases in both morbidity and mortality for cancer patients. The impact of non-index readmission after surgical management of brain tumors has not previously been evaluated. The authors set out to determine rates of non-index readmission following craniotomy for tumor resection and evaluated outcomes following index and non-index readmissions.METHODSRetrospective analyses of data from cases involving resection of a primary brain tumor were conducted using data from the Nationwide Readmissions Database (NRD) for 2010–2014. Multivariate logistic regression was used to evaluate the independent association of patient and hospital factors with readmission to an index versus non-index hospital. Further analysis evaluated association of non-index versus index hospital readmission with mortality and major complications during readmission. Effects of readmission hospital procedure volume on mortality and morbidity were evaluated in post hoc analysis.RESULTSIn a total of 17,459 unplanned readmissions, 84.4% patients were readmitted to index hospitals and 15.6% to non-index hospitals. Patient factors associated with increased likelihood of non-index readmission included older age (75+: OR 1.44, 95% CI 1.19–1.75), elective index admission (OR 1.19, 95% CI 1.08–1.30), increased Elixhauser comorbidity score ≥2 (OR 1.18, 95% CI 1.01–1.37), and malignant tumor diagnosis (OR 1.32, 95% CI 1.19–1.45) (all p < 0.04). Readmission to a non-index facility was associated with a 28% increase in major complications (OR 1.28, 95% CI 1.14–1.43, p < 0.001) and 21% increase in mortality (OR 1.21, 95% CI 1.02–1.44, p = 0.032) in initial analysis. Following a second multivariable logistic regression analysis including the readmitting hospital characteristics, low procedure volume of a readmitting facility was significantly associated with non-index readmission (p < 0.001). Readmission to a lower-procedure-volume facility was associated with a 46%–75% increase in mortality (OR 1.46–1.75, p < 0.005) and a 21%–35% increase in major complications (OR 1.21–1.34, p < 0.005). Following adjustment for volume at a readmitting facility, admission to a non-index facility was no longer associated with mortality (OR 0.90, 95% CI 0.71–1.14, p = 0.378) or major complications (OR 1.09, CI 0.94–1.26, p = 0.248).CONCLUSIONSOf patient readmissions following brain tumor resection, 15.6% occur at a non-index facility. Low procedure volume is a confounder for non-index analysis and is associated with an increased likelihood of major complications and mortality, as compared to readmission to high-procedure-volume hospitals. Further studies should evaluate interventions targeting factors associated with unplanned readmission.

Safety of immediate use of nonsteroidal antiinflammatory drugs after pediatric craniotomy for tumor

OBJECTIVEPostoperative pain can limit the recovery of children undergoing craniotomy for tumor resection, and pain management is highly variable between institutions and practitioners. Nonsteroidal antiinflammatory drugs (NSAIDs) are effective in treating postoperative pain following craniotomy, but their use has been limited by concerns about postoperative hemorrhage. The risk of postoperative hemorrhage is not insignificant in patients undergoing craniotomy for tumor resection. No study has specifically addressed the safety of NSAIDs in the immediate postoperative setting following craniotomy for tumor resection in pediatric patients.METHODSThe authors performed a retrospective cohort study in patients younger than 18 years of age who underwent craniotomy for tumor resection at a single tertiary referral center between 2009 and 2019. The study outcomes were 1) postoperative hemorrhage requiring return to the operating room for decompression, evacuation, or CSF diversion for hemorrhage-associated hydrocephalus; and 2) more-than-minimal hemorrhage on routine postoperative imaging. Patients receiving any NSAID in the hospital formulary on the same day as surgery (postoperative day zero [POD0]) were designated as such.RESULTSTwo hundred seventy-six children underwent 308 craniotomies for tumor resection over the study period. One hundred fifty-four patients (50.0%) received at least one dose of an NSAID on POD0. Six patients (1.9%) required a return to the operating room for a hemorrhagic complication, including 3 who received an NSAID on POD0 (OR 1.00, 95% CI 0.20–5.03). Seventeen patients (6.3% of patients imaged) had more-than-minimal hemorrhage on routine postoperative imaging, 9 of whom received an NSAID on POD0 (OR 1.08, 95% CI 0.40–2.89).CONCLUSIONSUse of NSAIDs on POD0 was not associated with either an increased risk of hemorrhage requiring a return to the operating room or asymptomatic hemorrhage on routine postoperative imaging. The overall incidence of clinically significant postoperative intracranial hemorrhage is low. These data support the use of NSAIDs as a safe measure for pain control in the postoperative setting for children undergoing craniotomy for tumor resection.