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Contralateral interhemispheric, transfalcine approach with asleep motor mapping for parasagittal lesions near the medial precentral gyrus

Michael A. Mooney and Nader Sanai

The contralateral interhemispheric approach has several advantages for approaching parasagittal lesions, including lesions involving or approaching the medial precentral gyrus. Supplementing the interhemispheric approach with asleep motor mapping is useful for confirming the location of the corticospinal tracts from the contralateral transfalcine corridor and identifying subcortical motor fibers at the deep aspect of the resection cavity. The authors describe the contralateral interhemispheric, transfalcine approach with asleep motor mapping to resect a parasagittal metastatic lesion involving the medial precentral gyrus.

The video can be found here: https://youtu.be/L-fJ6m5kOWs.

In Neurosurgical Focus Volume 45: Issue VideoSuppl2 (Oct 2018): Video Atlas - Intraoperative Brain Mapping

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Tumoral calcinosis of the craniovertebral junction as a cause of dysphagia with treatment by transoral decompression: case report

Michael A. Mooney, Mark E. Oppenlander, U. Kumar Kakarla, and Nicholas Theodore

Tumoral calcinosis is characterized by tumor-like deposition of calcium in periarticular soft tissue. Spinal involvement is rare, and perioperative diagnosis of tumoral calcinosis can be difficult because lesions may be confused with bony neoplasms. Symptoms of tumoral calcinosis result from bony involvement and/or direct compression of surrounding anatomical structures, for which treatment with surgical decompression can be highly successful. The craniovertebral junction is rarely affected by tumoral calcinosis, and patients with this condition may present with distinct symptoms. Herein, to their knowledge the authors present the first case of tumoral calcinosis affecting the craniovertebral junction in a patient who presented with severe dysphagia and required transoral decompression. Recognition of tumoral calcinosis by neurosurgeons is essential for facilitating diagnosis and treatment, and the transoral approach is an effective method for decompression in select patients.

In Journal of Neurosurgery: Spine Volume 26 (2017): Issue 5 (May 2017): Pages 547-652

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Patient out-of-pocket spending in cranial neurosurgery: single-institution analysis of 6569 consecutive cases and literature review

Seungwon Yoon, Michael A. Mooney, Michael A. Bohl, John P. Sheehy, Peter Nakaji, Andrew S. Little, and Michael T. Lawton

OBJECTIVE

With drastic changes to the health insurance market, patient cost sharing has significantly increased in recent years. However, the patient financial burden, or out-of-pocket (OOP) costs, for surgical procedures is poorly understood. The goal of this study was to analyze patient OOP spending in cranial neurosurgery and identify drivers of OOP spending growth.

METHODS

For 6569 consecutive patients who underwent cranial neurosurgery from 2013 to 2016 at the authors’ institution, the authors created univariate and multivariate mixed-effects models to investigate the effect of patient demographic and clinical factors on patient OOP spending. The authors examined OOP payments stratified into 10 subsets of case categories and created a generalized linear model to study the growth of OOP spending over time.

RESULTS

In the multivariate model, case categories (craniotomy for pain, tumor, and vascular lesions), commercial insurance, and out-of-network plans were significant predictors of higher OOP payments for patients (all p < 0.05). Patient spending varied substantially across procedure types, with patients undergoing craniotomy for pain ($1151 ± $209) having the highest mean OOP payments. On average, commercially insured patients spent nearly twice as much in OOP payments as the overall population. From 2013 to 2016, the mean patient OOP spending increased 17%, from $598 to $698 per patient encounter. Commercially insured patients experienced more significant growth in OOP spending, with a cumulative rate of growth of 42% ($991 in 2013 to $1403 in 2016).

CONCLUSIONS

Even after controlling for inflation, case-mix differences, and partial fiscal periods, OOP spending for cranial neurosurgery patients significantly increased from 2013 to 2016. The mean OOP spending for commercially insured neurosurgical patients exceeded $1400 in 2016, with an average annual growth rate of 13%. As patient cost sharing in health insurance plans becomes more prevalent, patients and providers must consider the potential financial burden for patients receiving specialized neurosurgical care.

In Neurosurgical Focus Volume 44: Issue 5 (May 2018): Neurosurgical Economics and Cost-Effectiveness

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Analysis of overlapping surgery in patients undergoing microsurgical aneurysm clipping: acute and long-term outcomes from the Barrow Ruptured Aneurysm Trial

Michael A. Mooney, Scott Brigeman, Michael A. Bohl, Elias D. Simon, John P. Sheehy, Steve W. Chang, and Robert F. Spetzler

OBJECTIVE

Overlapping surgery is a controversial subject in medicine today; however, few studies have examined the outcomes of this practice. The authors analyzed outcomes of patients with acutely ruptured saccular aneurysms who were treated with microsurgical clipping in a prospectively collected database from the Barrow Ruptured Aneurysm Trial. Acute and long-term outcomes for overlapping versus nonoverlapping cases were compared.

METHODS

During the study period, 241 patients with ruptured saccular aneurysms underwent microsurgical clipping. Patients were separated into overlapping (n = 123) and nonoverlapping (n = 118) groups based on surgical start/stop times. Outcomes at discharge and at 6 months, 1 year, 3 years, and 6 years after surgery were analyzed.

RESULTS

Patient variables (e.g., age, smoking status, cardiovascular history, Hunt and Hess grade, Fisher grade, and aneurysm size) were similar between the 2 groups. Aneurysm locations were similar, with the exception of the overlapping group having more posterior circulation aneurysms (18/123 [15%]) than the nonoverlapping group (8/118 [7%]) (p = 0.0495). Confirmed aneurysm obliteration at discharge was significantly higher for the overlapping group (109/119 [91.6%]) than for the nonoverlapping group (95/116 [81.9%]) (p = 0.03). Hospital length of stay, discharge location, and proportions of patients with a modified Rankin Scale (mRS) score > 2 at discharge and up to 6 years postoperatively were similar. The mean and median mRS, Glasgow Outcome Scale, Mini–Mental State Examination, National Institutes of Health Stroke Scale, and Barthel Index scores at all time points were not statistically different between the groups.

CONCLUSIONS

Compared with nonoverlapping surgery, overlapping surgery was not associated with worse outcomes for any variable at any time point, despite the complexity of the surgical management in this patient population. These findings should be considered during the discussion of future guidelines on the practice of overlapping surgery.

In Journal of Neurosurgery Volume 129: Issue 3 (Sep 2018): Pages 567-851

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Long-term results of middle cerebral artery aneurysm clipping in the Barrow Ruptured Aneurysm Trial

Michael A. Mooney, Elias D. Simon, Scott Brigeman, Peter Nakaji, Joseph M. Zabramski, Michael T. Lawton, and Robert F. Spetzler

OBJECTIVE

A direct comparison of endovascular versus microsurgical treatment of ruptured middle cerebral artery (MCA) aneurysms in randomized trials is lacking. As endovascular treatment strategies continue to evolve, the number of reports of endovascular treatment of these lesions is increasing. Herein, the authors report a detailed post hoc analysis of ruptured MCA aneurysms treated by microsurgical clipping from the Barrow Ruptured Aneurysm Trial (BRAT).

METHODS

The cases of patients enrolled in the BRAT who underwent microsurgical clipping for a ruptured MCA aneurysm were reviewed. Characteristics of patients and their clinical outcomes and long-term angiographic results were analyzed.

RESULTS

Fifty patients underwent microsurgical clipping of a ruptured MCA aneurysm in the BRAT, including 21 who crossed over from the endovascular treatment arm. Four patients with nonsaccular (e.g., dissecting, fusiform, or blister) aneurysms were excluded, leaving 46 patients for analysis. Most (n = 32; 70%) patients presented with a Hunt and Hess grade II or III subarachnoid hemorrhage, with a high prevalence of intraparenchymal blood (n = 23; 50%), intraventricular blood (n = 21; 46%), or both. At the last follow-up (up to 6 years after treatment), clinical outcomes were good (modified Rankin Scale score 0–2) in 70% (n = 19) of 27 Hunt and Hess grades I–III patients and in 36% (n = 4) of 11 Hunt and Hess grade IV or V patients. There were no instances of rebleeding after the surgical clipping of aneurysms in this series at the time of last clinical follow-up.

CONCLUSIONS

Microsurgical clipping of ruptured MCA aneurysms has several advantages over endovascular treatment, including durability over time. The authors report detailed outcome data of patients with ruptured MCA aneurysms who underwent microsurgical clipping as part of a prospective, randomized trial. These results should be used for comparison with future endovascular and surgical series to ensure that the best results are being achieved for patients with ruptured MCA aneurysms.

In Journal of Neurosurgery Volume 130: Issue 3 (Mar 2019): Pages 675-1038

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Interrater and intrarater reliability of the Knosp scale for pituitary adenoma grading

Michael A. Mooney, Douglas A. Hardesty, John P. Sheehy, Robert Bird, Kristina Chapple, William L. White, and Andrew S. Little

OBJECTIVE

The goal of this study was to determine the interrater and intrarater reliability of the Knosp grading scale for predicting pituitary adenoma cavernous sinus (CS) involvement.

METHODS

Six independent raters (3 neurosurgery residents, 2 pituitary surgeons, and 1 neuroradiologist) participated in the study. Each rater scored 50 unique pituitary MRI scans (with contrast) of biopsy-proven pituitary adenoma. Reliabilities for the full scale were determined 3 ways: 1) using all 50 scans, 2) using scans with midrange scores versus end scores, and 3) using a dichotomized scale that reflects common clinical practice. The performance of resident raters was compared with that of faculty raters to assess the influence of training level on reliability.

RESULTS

Overall, the interrater reliability of the Knosp scale was “strong” (0.73, 95% CI 0.56–0.84). However, the percent agreement for all 6 reviewers was only 10% (26% for faculty members, 30% for residents). The reliability of the middle scores (i.e., average rated Knosp Grades 1 and 2) was “very weak” (0.18, 95% CI −0.27 to 0.56) and the percent agreement for all reviewers was only 5%. When the scale was dichotomized into tumors unlikely to have intraoperative CS involvement (Grades 0, 1, and 2) and those likely to have CS involvement (Grades 3 and 4), the reliability was “strong” (0.60, 95% CI 0.39–0.75) and the percent agreement for all raters improved to 60%. There was no significant difference in reliability between residents and faculty (residents 0.72, 95% CI 0.55–0.83 vs faculty 0.73, 95% CI 0.56–0.84). Intrarater reliability was moderate to strong and increased with the level of experience.

CONCLUSIONS

Although these findings suggest that the Knosp grading scale has acceptable interrater reliability overall, it raises important questions about the “very weak” reliability of the scale's middle grades. By dichotomizing the scale into clinically useful groups, the authors were able to address the poor reliability and percent agreement of the intermediate grades and to isolate the most important grades for use in surgical decision making (Grades 3 and 4). Authors of future pituitary surgery studies should consider reporting Knosp grades as dichotomized results rather than as the full scale to optimize the reliability of the scale.

In Journal of Neurosurgery Volume 126 (2017): Issue 5 (May 2017): Pages 1445-1746

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Laser scanning confocal endomicroscopy in the neurosurgical operating room: a review and discussion of future applications

Michael A. Mooney, Aqib H. Zehri, Joseph F. Georges, and Peter Nakaji

Laser scanning confocal endomicroscopy (LSCE) is an emerging technology for examining brain neoplasms in vivo. While great advances have been made in macroscopic fluorescence in recent years, the ability to perform confocal microscopy in vivo expands the potential of fluorescent tumor labeling, can improve intraoperative tissue diagnosis, and provides real-time guidance for tumor resection intraoperatively. In this review, the authors highlight the technical aspects of confocal endomicroscopy and fluorophores relevant to the neurosurgeon, provide a comprehensive summary of LSCE in animal and human neurosurgical studies to date, and discuss the future directions and potential for LSCE in neurosurgery.

In Neurosurgical Focus Volume 36 (2014): Issue 2 (Feb 2014): Application of Fluorescent Technology in Neurosurgery

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Postoperative 30-day emergency department utilization after 7294 cranial neurosurgery procedures at a tertiary neuroscience center

Douglas A. Hardesty, Michael A. Mooney, Benjamin K. Hendricks, Joshua S. Catapano, Scott T. Brigeman, Michael A. Bohl, John P. Sheehy, and Andrew S. Little

OBJECTIVE

Hospital readmission and the reduction thereof has become a major quality improvement initiative in organized medicine and neurosurgery. However, little research has been performed on why neurosurgical patients utilize hospital emergency rooms (ERs) with or without subsequent admission in the postoperative setting.

METHODS

This study was a retrospective, single-center review of data for all surgical cranial procedures performed from July 2013 to July 2016 in patients who survived to discharge. The study was approved by the institutional review board of the participating medical center.

RESULTS

The authors identified 7294 cranial procedures performed during 6596 hospital encounters in 5385 patients. The rate of postoperative ER utilization within 30 days after surgical hospitalization across all procedure types was 13.1 per 100 surgeries performed. The two most common chief complaints were pain (30.7%) and medical complication (18.2%). After identification of relevant surgical and patient factors with univariable analysis, a multivariable backward elimination logistic regression model was constructed in which Ommaya reservoir placement (OR 2.65, p = 0.0008) and cranial CSF shunt placement (OR 1.40, p = 0.0001) were associated with increased ER utilization. Deep brain stimulation electrode placement (OR 0.488, p = 0.0004), increasing hospital length of stay (OR 0.935, p < 0.0001), and increasing patient age (OR 0.988, p < 0.0001) were associated with lower rates of postoperative ER utilization. One-half (50%) of ER visit patients were readmitted to the hospital. New/worsening neurological deficit chief complaint (OR 1.99, p = 0.0088), fever chief complaint (OR 2.41, p = 0.0205), altered mentation chief complaint (OR 2.71, p = 0.0002), patient chronic kidney disease (OR 3.31, p = 0.0037), brain biopsy procedure type (OR 3.50, p = 0.0398), and wound infection chief complaint (OR 31.4, p = 0.0008) were associated with increased rates of readmission to the hospital from the ER in multivariable analysis.

CONCLUSIONS

The authors report the rates of and reasons for ER utilization in a large cohort of postoperative cranial neurosurgical patients. Factors identified were associated with both increased and decreased use of the ER after cranial surgery, as well as variables associated with readmission to the hospital after postoperative ER visitation. These findings may direct future quality improvement via prospective implementation of care pathways for high-risk procedures.

In Journal of Neurosurgery Publish Before Print

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A novel proposed grading system for cerebellar arteriovenous malformations

Peyton L. Nisson, Salman A. Fard, Christina M. Walter, Cameron M. Johnstone, Michael A. Mooney, Ali Tayebi Meybodi, Michael Lang, Helen Kim, Heidi Jahnke, Denise J. Roe, Travis M. Dumont, G. Michael Lemole Jr., Robert F. Spetzler, and Michael T. Lawton

OBJECTIVE

The objective of this study was to evaluate the existing Spetzler-Martin (SM), Spetzler-Ponce (SP), and Lawton-Young (LY) grading systems for cerebellar arteriovenous malformations (AVMs) and to propose a new grading system to estimate the risks associated with these lesions.

METHODS

Data for patients with cerebellar AVMs treated microsurgically in two tertiary medical centers were retrospectively reviewed. Data from patients at institution 1 were collected from September 1999 to February 2013, and at institution 2 from October 2008 to October 2015. Patient outcomes were classified as favorable (modified Rankin Scale [mRS] score 0–2) or poor (mRS score 3–6) at the time of discharge. Using chi-square and logistic regression analysis, variables associated with poor outcomes were assigned risk points to design the proposed grading system. The proposed system included neurological status prior to treatment (poor, +2 points), emergency surgery (+1 point), age > 60 years (+1 point), and deep venous drainage (deep, +1 point). Risk point totals of 0–1 comprised grade 1, 2–3 grade 2, and 4–5 grade 3.

RESULTS

A total of 125 cerebellar AVMs of 1328 brain AVMs were reviewed in 125 patients, 120 of which were treated microsurgically and included in the study. With our proposed grading system, we found poor outcomes differed significantly between each grade (p < 0.001), while with the SM, SP, and LY grading systems they did not (p = 0.22, p = 0.25, and p = 1, respectively). Logistic regression revealed grade 2 had 3.3 times the risk of experiencing a poor outcome (p = 0.008), while grade 3 had 9.9 times the risk (p < 0.001). The proposed grading system demonstrated a superior level of predictive accuracy (area under the receiver operating characteristic curve [AUROC] of 0.72) compared with the SM, SP, and LY grading systems (AUROC of 0.61, 0.57, and 0.51, respectively).

CONCLUSIONS

The authors propose a novel grading system for cerebellar AVMs based on emergency surgery, venous drainage, preoperative neurological status, and age that provides a superior prognostication power than the formerly proposed SM, SP, and LY grading systems. This grading system is clinically predictive of patient outcomes and can be used to better guide vascular neurosurgeons in clinical decision-making.

In Journal of Neurosurgery Volume 132: Issue 4 (Apr 2020): Pages 987-1311

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Immediate ex-vivo diagnosis of pituitary adenomas using confocal reflectance microscopy: a proof-of-principle study

Michael A. Mooney, Joseph Georges, Mohammedhassan Izady Yazdanabadi, Katherine Y. Goehring, William L. White, Andrew S. Little, Mark C. Preul, Stephen W. Coons, Peter Nakaji, and Jennifer M. Eschbacher

OBJECTIVE

The objective of this study was to evaluate the feasibility of using confocal reflectance microscopy (CRM) ex vivo to differentiate adenoma from normal pituitary gland in surgical biopsy specimens. CRM allows for rapid, label-free evaluation of biopsy specimens with cellular resolution while avoiding some limitations of frozen section analysis.

METHODS

Biopsy specimens from 11 patients with suspected pituitary adenomas were transported directly to the pathology department. Samples were immediately positioned and visualized with CRM using a confocal microscope located in the same area of the pathology department where frozen sections are prepared. An H & E–stained slide was subsequently prepared from imaged tissue. A neuropathologist compared the histopathological characteristics of the H & E–stained slide and the matched CRM images. A second neuropathologist reviewed images in a blinded fashion and assigned diagnoses of adenoma or normal gland.

RESULTS

For all specimens, CRM contrasted cellularity, tissue architecture, nuclear pleomorphism, vascularity, and stroma. Pituitary adenomas demonstrated sheets and large lobules of cells, similar to the matched H & E–stained slides. CRM images of normal tissue showed scattered small lobules of pituitary epithelial cells, consistent with matched H & E–stained images of normal gland. Blinded review by a neuropathologist confirmed the diagnosis in 15 (94%) of 16 images of adenoma versus normal gland.

CONCLUSIONS

CRM is a simple, reliable approach for rapidly evaluating pituitary adenoma specimens ex vivo. This technique can be used to accurately differentiate between pituitary adenoma and normal gland while preserving biopsy tissue for future permanent analysis, immunohistochemical studies, and molecular studies.

In Journal of Neurosurgery Volume 128: Issue 4 (Apr 2018): Pages 961-1272