Barrow Innovation Center: A 5-Year Update and Future Direction.

OBJECTIVE: The rich history of neurosurgical innovation served as a model for the Barrow Innovation Center's establishment in 2016. The center's accomplishments are summarized in hopes of fostering the development of similar centers and initiatives within the neurosurgical and broader medical community. METHODS: A retrospective review (January 2016-July 2021) of patent filings, project proposals, and funding history was used to generate the data presented in this operational review. RESULTS: Through the 5-year period of analysis, 55 prior art searches were conducted on new patentable ideas. A total of 87 provisional patents, 25 Patent Cooperation Treaty applications, and 48 national stage filings were submitted. In partnership with Arizona State University, the University of Arizona, California Polytechnic State University, and Texas A&M University, a total of 27 multidisciplinary projects were conducted with input from multispecialty engineers and scientists. These efforts translated into 1 startup company and 2 licensed patents to commercial companies, with most remaining ideas and project efforts awaiting interest from industry. CONCLUSIONS: The multidisciplinary collaborative environment embodied by the Barrow Innovation Center has revolutionized the innovative and entrepreneurial environment of its home institution and enabled neurosurgical residents to get a unique educational experience within the realm of innovation. The bottleneck within the workflow of ideas from conception to commercialization appears to be the establishment of commercial partners; therefore, future efforts within the center will be to establish a panel of industry partnerships to enhance the exposure of ideas to interested companies.

Effects of a transsphenoidal surgery quality improvement program on patient outcomes and hospital financial performance.

OBJECTIVE: A comprehensive quality improvement (QI) program aimed at all aspects of patient care after pituitary surgery was initiated at a single center. This initiative was guided by standard quality principles to improve patient outcomes and optimize healthcare value. The programmatic goal was to discharge most elective patients within 1 day after surgery, improve patient safety, and limit unplanned readmissions. The program is described, and its effect on patient outcomes and hospital financial performance over a 5-year period are investigated. METHODS: Details of the patient care pathway are presented. Foundational elements of the QI program include evidence-based care pathways (e.g., for hyponatremia and pain), an in-house research program designed to fortify care pathways, patient education, expectation setting, multidisciplinary team care, standard order sets, high-touch postdischarge care, outcomes auditing, and a patient navigator, among other elements. Length of stay (LOS), outcome variability, 30-day unplanned readmissions, and hospital financial performance were identified as surrogate endpoints for healthcare value for the surgical epoch. To assess the effect of these protocols, all patients undergoing elective transsphenoidal surgery for pituitary tumors and Rathke's cleft cysts between January 2015 and December 2019 were reviewed. RESULTS: A total of 609 adult patients who underwent elective surgery by experienced pituitary surgeons were identified. Patient demographics, comorbidities, and payer mix did not change significantly over the study period (p ≥ 0.10). The mean LOS was significantly shorter in 2019 versus 2015 (1.6 ± 1.0 vs 2.9 ± 2.2 midnights, p < 0.001). The percentage of patients discharged after 1 midnight was significantly higher in 2019 versus 2015 (75.4% vs 15.6%, p < 0.001). The 30-day unplanned hospital readmission rate decreased to 2.8% in 2019 from 8.3% in 2015. Per-patient hospital profit increased 71.3% ($10,613 ± $19,321 in 2015; $18,180 ± $21,930 in 2019), and the contribution margin increased 42.3% ($18,925 ± $19,236 in 2015; $26,939 ± $22,057 in 2019), while costs increased by only 3.4% ($18,829 ± $6611 in 2015; $19,469 ± $4291 in 2019). CONCLUSIONS: After implementation of a comprehensive pituitary surgery QI program, patient outcomes significantly improved, outcome variability decreased, and hospital financial performance was enhanced. Future studies designed to evaluate disease remission, patient satisfaction, and how the surgeon learning curve may synergize with other quality efforts may provide additional context.

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

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.

Mean arterial pressure maintenance following spinal cord injury: Does meeting the target matter?

INTRODUCTION: Neurosurgical guidelines recommend maintaining mean arterial pressure (MAP) between 85 and 90 mm Hg following acute spinal cord injury (SCI). In our hospital, SCI patients receive orders for MAP targeting for 72 hours following admission, but it is unclear how often the patient's MAP meets the target and whether or not this affects outcome. We hypothesized that the proportion of MAP measurements ≥85 mm Hg would be associated with neurologic recovery. METHODS: Spinal cord injury patients with blunt mechanism of injury admitted between 2014 and 2019 were identified from the registry of a level 1 trauma center. Proportion of MAP values ≥85 mm Hg was calculated for each patient. Neurologic improvement, as measured by positive change in American Spinal Injury Association (ASIA) impairment scale by ≥1 level from admission to discharge was evaluated with respect to proportion of elevated MAP values. RESULTS: A total of 136 SCI patients were evaluated. Average proportion of elevated MAP values was 75%. Admission ASIA grades were as follows: A, 30 (22.1%); B, 20 (14.7%); C, 28 (20.6%); and D, 58 (42.6%). One hundred six patients (77.9%) required vasopressors to elevate MAP (ASIA A, 86.7%; B, 95.0%; C, 92.9%; D, 60.3%). Forty patients (29.4%) were observed to have improvement in ASIA grade by discharge (admission ASIA A, 15%; B, 33%; C, 40%; D, 13%). The proportion of elevated MAP values was higher for patients with neurologic improvement (0.81 ± 0.15 vs. 0.72 ± 0.25, p = 0.014). Multivariate modeling demonstrated a significant association between proportion of elevated MAP values and neurologic improvement (p = 0.028). An interaction revealed this association to be moderated by vasopressor dose (p = 0.032). CONCLUSION: The proportion of MAP measurements ≥85 mm Hg was determined to be an independent predictor of neurologic improvement. Increased vigilance regarding MAP maintenance above 85 mm Hg is warranted to optimize neurologic recovery following SCI. LEVEL OF EVIDENCE: Therapeutic/care management, level IV.

Selective posterior cerebral artery amobarbital test: a predictor of memory following subtemporal selective amygdalohippocampectomy.

BACKGROUND: The selective posterior cerebral artery (PCA) amobarbital test, or PCA Wada test, is used to predict memory impairment after epilepsy surgery in patients who have previously had a failed internal carotid artery (ICA) amobarbital test. METHODS: Medical records from 2012 to 2018 were retrospectively reviewed for all patients with seizures who underwent a selective PCA Wada test at our institution following a failed or inconclusive ICA Wada test. Standardized neuropsychological testing was performed before and during the Wada procedure and postoperatively in patients who underwent resection. RESULTS: Thirty-three patients underwent a selective PCA Wada test, with no complications. Twenty-six patients with medically refractory epilepsy had a seizure focus amenable to selective amygdalohippocampectomy (AHE). Six patients (23%, n=26) had a failed PCA Wada test and did not undergo selective AHE, seven (27%) declined surgical resection, leaving 13 patients who underwent subtemporal selective AHE. Hippocampal sclerosis was found in all 13 patients (100%). Twelve patients (92%) subsequently underwent formal neuropsychological testing and all were found to have stable memory. Ten patients (77%) were seizure-free (Engel Class I), with average follow-up of 13 months. CONCLUSION: The selective PCA Wada test is predictive of memory outcomes after subtemporal selective AHE in patients with a failed or inconclusive ICA Wada test. Furthermore, given the low risk of complications and potential benefit of seizure freedom, a selective PCA Wada test may be warranted in patients with medically intractable epilepsy who are candidates for a selective AHE and who have a prior failed or inconclusive ICA Wada test.

Standardized Ventriculostomy Protocol without an Occlusive Dressing: Results of an Observational Study in Patients with Aneurysmal Subarachnoid Hemorrhage.

BACKGROUND: Catheter-related infections are a potentially life-threatening complication of having an external ventricular drain (EVD). Patients with aneurysmal subarachnoid hemorrhage (aSAH) are at increased risk of infection associated with prolonged ventricular drainage, with a reported mean infection rate of 6%. We report the EVD-associated infection rate among patients with aSAH managed with a unique standardized treatment protocol without an occlusive EVD dressing. METHODS: Patients with aSAH admitted from August 2015 through August 2017 were retrospectively analyzed for EVD placement. Cerebrospinal fluid (CSF) samples were obtained twice weekly for culture and routine studies. EVD-associated infection was defined as growth of CSF cultures. RESULTS: During the 2-year study period, 122 patients presented with an aSAH, with 91 (74.6%) having EVD placement. In patients with EVDs, the mean age was 57.9 years (68% women); 88% of aSAHs were Fisher grade III or IV. Mean duration of EVD was 14 days, and 13% of patients required EVD replacement. Endovascular coiling and surgical clipping were performed in 34 (37%) and 53 (58%) patients with EVD, respectively. A total of 347 CSF studies were performed with no EVD-associated infections. There were 3 CSF samples with false-positive Gram stain results but no growth on concurrent or multiple repeat cultures. CONCLUSIONS: Using a standardized protocol for placement and management of EVDs in patients with aSAH is associated with low risk of CSF infection. Our study demonstrates that occlusive EVD dressings are not necessary and that routine CSF sampling in patients with EVD may lead to false-positive findings and unnecessary antibiotic administration.

Flow diverters as a scaffold for treating direct carotid cavernous fistulas.

BACKGROUND: Direct carotid-cavernous sinus fistulas (dCCFs) are high flow arteriovenous shunts between the internal carotid artery and the cavernous sinus. Recently, we have used the pipeline embolization device (PED) to treat dCCFs. METHODS: We describe our experience treating patients with dCCFs in whom the PED was placed as the primary treatment modality. RESULTS: Five patients with dCCFs were treated with PEDs deployed in the ipsilateral internal carotid artery spanning the fistula. All patients also underwent either adjunctive transvenous or transarterial embolization. The PED served both as the primary treatment modality and as a scaffold that facilitated safe and efficacious transvenous embolysate administration by altering the flow dynamics through the fistula and providing a physical barrier that protected the internal carotid artery. No intraoperative or perioperative complications occurred. One of the five patients exhibited complete angiographic resolution of the fistula immediately after the procedure. The remaining four patients experienced complete obliteration of the fistula without additional treatment, which suggests that the PED induced alteration promoted thrombosis of the fistula. Therefore, 100% of patients in this series exhibited complete and durable obliteration of the fistula and complete resolution of symptoms following treatment. CONCLUSIONS: We believe that use of the PED to treat dCCFs may be a safe and efficacious strategy that facilitates parent vessel protection during transvenous embolization. Furthermore, the flow alterations induced by the PED may promote thrombosis of incompletely occluded fistulas. This is the largest reported series of non-iatrogenic dCCFs treated with use of the PED as the primary initial treatment strategy.

Association of Angiotensin-Converting Enzyme Inhibitors with Increased Mortality Among Patients with Isolated Severe Traumatic Brain Injury.

BACKGROUND: Traumatic brain injury (TBI) is associated with one-third of all deaths from trauma. Preinjury exposure to cardiovascular drugs may affect TBI outcomes. Angiotensin-converting enzyme inhibitors (ACEIs) exacerbate brain cell damage and worsen functional outcomes in the laboratory setting. ß-blockers (BBs), however, appear to be associated with reduced mortality among patients with isolated TBI. OBJECTIVE: Examine the association between preinjury ACEI and BB use and clinical outcome among patients with isolated TBI. METHODS: A retrospective cohort study of patients age ≥ 40 years admitted to an academic level 1 trauma center with isolated TBI between January 2010 and December 2014 was performed. Isolated TBI was defined as a head Abbreviated Injury Scale (AIS) score ≥ 3, with chest, abdomen, and extremity AIS scores ≤ 2. Preinjury medication use was determined through chart review. All patients with concurrent BB use were initially excluded. In-hospital mortality was the primary measured outcome. RESULTS: Over the 5-year study period, 600 patients were identified with isolated TBI who were naive to BB use. There was significantly higher mortality (P = .04) among patients who received ACEI before injury (10 of 96; 10%) than among those who did not (25 of 504; 5%). A multivariate stepwise logistic regression analysis revealed a threefold increased risk of mortality in the ACEI cohort (P < .001), which was even greater than the twofold increased risk of mortality associated with an Injury Severity Score ≥ 16. A second analysis that included patients who received preinjury BBs (n = 98) demonstrated slightly reduced mortality in the ACEI cohort with only a twofold increased risk in multivariate analysis (P = .05). CONCLUSIONS: Preinjury exposure to ACEIs is associated with an increase in mortality among patients with isolated TBI. This effect is ameliorated in patients who receive BBs, which provides evidence that this class of medications may provide a protective benefit.

Iatrogenic pseudoaneurysm rupture of the anterior cerebral artery after placement of an external ventricular drain, treated with clip-wrapping: a case report and review of the literature.

External ventricular drains (EVDs) are often placed emergently for patients with hydrocephalus, which carries a risk of hemorrhage. Rarely, rupture of a pseudoaneurysm originating from an EVD placement precipitates such a hemorrhage. An EVD was placed in a patient with a ruptured left posterior communicating artery aneurysm who later underwent endovascular coil embolization. On post-bleed day 20, a distal right anterior cerebral artery pseudoaneurysm along the EVD tract ruptured, which was successfully treated via clip-wrapping. Although EVD-associated pseudoaneurysms are rare, they have a high propensity for rupture. Early treatment of these lesions should be considered to prevent neurologic deterioration.

The Prognostic Significance of a Cast Fourth Ventricle in Ruptured Aneurysm Patients With Intraventricular Hemorrhage in the Barrow Ruptured Aneurysm Trial (BRAT).

BACKGROUND: Ruptured aneurysms causing intraventricular hemorrhage (IVH) are associated with high morbidity. The presence of blood that completely fills the fourth ventricle (cast fourth ventricle, CFV) is thought to be particularly ominous, but studies documenting the outcome of such cases are lacking. OBJECTIVE: To investigate the outcomes of patients with aneurysmal subarachnoid hemorrhage (aSAH) and CFV. METHODS: We reviewed 406 patients enrolled in the Barrow Ruptured Aneurysm Trial (BRAT, NCT01593267, clinicaltrials.gov); 238 patients with aSAH and IVH were identified, and imaging was reviewed for the presence of CFV. Outcome was evaluated at the 1-yr follow-up. A poor outcome was defined as modified Rankin Scale score >2. RESULTS: CFV was identified in 25 patients. Admission Glasgow Coma Score was lower in CFV patients, 7.8 versus 11.5 (P < .001). At discharge and the 1-yr follow-up, patients with CFV had a greater risk of a poor outcome (P < .001 and P = .002, respectively). In a subgroup analysis of 79 patients with IVH and initial Glasgow Coma Score ≤ 8, almost 50% of the patients with IVH but without CFV had made a good recovery versus 7% of patients with CFV (odds ratio [OR] 15, P = .002). On multivariate analysis, CFV was a greater predictor of a poor prognosis at 1 yr post-aSAH than Hunt and Hess grade >3 (6.4 OR vs 2.9 OR [P < .001], respectively). CONCLUSION: The presence of CFV is a predictor of poor outcome in patients with aSAH. When compared to other patients with IVH and aSAH, CFV is a stronger predictor of a poor outcome than a poor Hunt and Hess Grade.

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

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 0­2) in 70% (n = 19) of 27 Hunt and Hess grades I­III 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.

Treadmill associated head injuries on the rise: an 18 year review of U.S. emergency room visits.

OBJECTIVE: The treadmill is the most commonly used aerobic exercise equipment with studies showing many gym-related injuries are attributed to treadmills. The purpose of this study is to examine the incidence of treadmill-associated head injuries within the US. METHODS: Retrospective data from 1997 to 2014 was collected via the National Electronic Injury Surveillance System, which provides annual es7timates of injuries associated with consumer products. Patients over 18 years who sustained treadmill-associated head injuries were included, and the estimated annual incidence was determined. RESULTS: An estimated 4929 patients presented to US emergency departments with a head injury while exercising on a treadmill between 1997 and 2014. A >1000% increase in the number of head injuries was observed over the study period (p-value <0.001). Patients over 50 had a 14 times greater risk of admission than younger patients (p-value <0.001). Injuries were greater in women than men. CONCLUSION: Our study demonstrates a significant increase treadmill-associated head injuries from 1997 to 2014. This phenomenon is most pronounced in older and female populations. The exact etiology of this large increase remains unclear. Education on the proper use of treadmills as well as further investigation into the cause of the increase are warranted.

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

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.

Rapid and complete radiological resolution of an intradural cervical cord lung cancer metastasis treated with spinal stereotactic radiosurgery: case report.

Stereotactic radiosurgery (SRS) has emerged as a treatment option for patients with spinal metastatic disease. Although SRS has been shown to be successful in a multitude of extradural metastatic tumors causing cord compression, very few cases of intradural treatment have been reported. The authors present a rare case of an intradural extramedullary metastatic small cell lung cancer lesion to the cervical spine resulting in cord compression in an area that had also been extensively pretreated with conventional external-beam radiation therapy. The patient underwent successful SRS to this metastatic site, with rapid and complete resolution of his lesion.

Pedicolaminar Fracture-Dislocation.

A 28-year-old man presented to a level 1 trauma center with significant cervical spine pain after sliding into third base during a softball game. He struck his head on the thigh of the defensive player and had immediate pain in his neck and arm. He reported no loss of consciousness, no transient tetraplegia/paraplegia, and no loss of bowel and bladder control. After initial imaging, enhanced computed tomography scans were obtained.