A1 segment hypoplasia associated with cerebral infarction after anterior communicating artery aneurysm rupture.

BACKGROUND: Congenital hypoplasia or absence of the A1 segment of the anterior cerebral artery (ACA) has been associated with increased incidence of berry aneurysms at the anterior communicating artery (Acom) complex. It is not known, however, whether this anatomic variant also predisposes patients to complications after aneurysmal subarachnoid hemorrhage. METHODS: Patients were included for analysis if they presented to our institution for clipping or coiling of an Acom aneurysm between the years of 2001 and 2013. Patients were deemed to have cerebral infarction if a new hypodensity in a vascular distribution was visualized on CT imaging. The association between A1 segmental abnormalities and radiologic infarction was subsequently evaluated in a risk-adjusted manner using stepwise multivariable logistic regression analysis. RESULTS: Of 145 patients who presented with aneurysmal subarachnoid hemorrhage after rupture of an Acom aneurysm, 31 (21.4%) had a hypoplastic or absent A1 segment. On univariate analysis, there was a trend toward an increased rate of radiologic infarction in patients with A1 segment abnormalities (OR=2.11, 95% CI: 0.93-4.79; P=0.0757). On multivariable analysis, a hypoplastic or absent A1 segment was significantly associated with an increased rate of radiologic infarction (OR=2.54, 95% CI: 1.02-6.43; P=0.0466). CONCLUSIONS: Our results suggest that a hypoplastic or absent A1 segment is associated with cerebral infarction following subarachnoid hemorrhage from ruptured Acom aneurysms, indicating a potential need for heightened vigilance and a reduced threshold for therapeutic intervention in patients harboring this abnormality.

Allograft versus autograft in cervical and lumbar spinal fusions: an examination of operative time, length of stay, surgical site infection, and blood transfusions.

BACKGROUND: Autograft harvesting for spine arthrodesis has been associated with longer operative times and increased blood loss. Allograft compared to autograft in spinal fusions has not been studied in a multicenter cohort. METHODS: Patients enrolled in the ACS-NSQIP registry between 2012 and 2013 who underwent cervical or lumbar spinal fusion with either allograft or autograft through a separate incision were included for analysis. The primary outcomes of interest were operative time, length of stay, blood transfusion, and surgical site infection (SSI). RESULTS: A total of 6790 and 6718 patients received a cervical or lumbar spinal fusion, respectively. On unadjusted analysis in both cervical and lumbar cohorts, autograft was associated with increased rates of blood transfusion (cervical: 2.9% vs. 1.0%, P<0.001; and lumbar: 21.0% vs. 15.7%, P<0.001) and increased operative time (cervical: 167 vs. 128 minutes, P<0.001; and lumbar: 226 vs. 204 minutes, P<0.001) relative to allograft. On multivariable analysis in both the cervical and lumbar cohorts, autograft was associated with increased odds of blood transfusion (cervical: OR=2.3, 95% CI: 1.0-5.1; and lumbar: OR=1.3, 95% CI: 1.1-1.6) and longer operative times (cervical: 27.8 minutes, 95% CI: 20.7-35.0; and lumbar: 25.4 minutes, 95% CI: 17.7-33.1) relative to allograft. Autograft was not associated with either length of stay or SSI. CONCLUSIONS: In a multicenter cohort of patients undergoing cervical or lumbar spinal fusion, autograft was associated with increased rates of blood transfusion and increased operative time relative to allograft.

Radiation-Induced Cavernous Malformations After Single-Fraction Meningioma Radiosurgery.

BACKGROUND: Stereotactic radiosurgery (SRS) is a commonly performed procedure for patients with intracranial meningiomas. OBJECTIVE: To describe the clinical features of patients with radiation-induced cavernous malformations (RICM) after single-fraction meningioma SRS. METHODS: Retrospective study of patients having single-fraction SRS for intracranial meningioma at our center from 1990 through 2009, and 1 patient who had single-fraction SRS elsewhere. Patients were excluded if they refused research authorization (n = 7), had a World Health Organization Grade II or III meningioma (n = 65), had a genetic predisposition for tumor development (n = 52), had prior or concurrent radiation therapy (n = 49), or had less than 2 yr of magnetic resonance imaging follow-up after SRS (n = 77). The median follow-up of the remaining 426 patients was 7.9 yr (range, 2-24.9). RESULTS: Three RICM (0.7%) were identified at 2, 10, and 21 yr after SRS. Two patients were asymptomatic, whereas 1 patient had a brainstem hemorrhage causing facial weakness and numbness. The risk of developing an RICM after SRS was 0.2% at 5 yr and 0.9% at 15 yr. All patients were observed and remained stable without additional bleeding in follow-up of 7, 12.8, and 2 yr, respectively. A fourth patient developed progressive neurological dysfunction starting 7 yr after SRS at another center and was treated for several years with bevacizumab without improvement. Surgical resection was performed 11.5 yr after SRS and histologic examination was consistent with an RICM. CONCLUSION: The risk of RICM after single-fraction SRS for intracranial meningiomas is very low, but the latency period noted until their detection emphasizes the need for extended imaging follow-up after SRS of benign lesions.

Risk Factors for Readmission with Cerebrospinal Fluid Leakage Within 30 Days of Vestibular Schwannoma Surgery.

BACKGROUND: Cerebrospinal fluid (CSF) leak is a well-recognized complication after surgical resection of vestibular schwannomas and is associated with a number of secondary complications, including readmission and meningitis. OBJECTIVE: To identify risk factors for and timing of 30-d readmission with CSF leak. METHODS: Patients who had undergone surgical resection of a vestibular schwannoma from 1995 to 2010 were identified in the California Office of Statewide Health Planning and Development database. The most common admission diagnoses were identified by International Classification of Disease, ninth Revision, diagnosis codes, and predictors of readmission with CSF leak were determined using logistic regression. RESULTS: A total of 6820 patients were identified. CSF leak, though a relatively uncommon cause of admission after discharge (3.52% of all patients), was implicated in nearly half of 490 readmissions (48.98%). Significant independent predictors of readmission with CSF leak were male sex (odds ratio [OR] 1.72, 95% confidence interval [CI] 1.32-2.25), first admission at a teaching hospital (OR 3.32, 95% CI 1.06-10.39), CSF leak during first admission (OR 1.84, 95% CI 1.33-2.55), obesity during first admission (OR 2.10, 95% CI 1.20-3.66), and case volume of first admission hospital (OR of log case volume 0.82, 95% CI 0.70-0.95). Median time to readmission was 6 d from hospital discharge. CONCLUSION: This study has quantified CSF leak as an important contributor to nearly half of all readmissions following vestibular schwannoma surgery. We propose that surgeons should focus on technical factors that may reduce CSF leakage and take advantage of potential screening strategies for the detection of CSF leakage prior to first admission discharge.

Impact of neurosurgeon specialization on patient outcomes for intracranial and spinal surgery: a retrospective analysis of the Nationwide Inpatient Sample 1998-2009.

OBJECTIVE The subspecialization of neurosurgical practice is an ongoing trend in modern neurosurgery. However, it remains unclear whether the degree of surgeon specialization is associated with improved patient outcomes. The authors hypothesized that a trend toward increased neurosurgeon specialization was associated with improved patient morbidity and mortality rates. METHODS The Nationwide Inpatient Sample (NIS) was used (1998-2009). Patients were included in a spinal analysis cohort for instrumented spine surgery involving the cervical spine ( International Classification of Diseases, Ninth Revision, Clinical Modification [ICD-9-CM] codes 81.31-81.33, 81.01-81.03, 84.61-84.62, and 84.66) or lumbar spine (codes 81.04-81.08, 81.34-81.38, 84.64-84.65, and 84.68). A cranial analysis cohort consisted of patients receiving a parenchymal excision or lobectomy operation (codes 01.53 and 01.59). Surgeon specialization was measured using unique surgeon identifiers in the NIS and defined as the proportion of a surgeon's total practice dedicated to cranial or spinal cases. RESULTS A total of 46,029 and 231,875 patients were identified in the cranial and spinal analysis cohorts, respectively. On multivariate analysis in the cranial analysis cohort (after controlling for overall surgeon volume, patient demographic data/comorbidities, hospital characteristics, and admitting source), each percentage-point increase in a surgeon's cranial specialization (that is, the proportion of cranial cases) was associated with a 0.0060 reduction in the log odds of patient mortality (95% CI 0.0034-0.0086) and a 0.0042 reduction in the log odds of morbidity (95% CI 0.0032-0.0052). This resulted in a 15% difference in the predicted probability of mortality for neurosurgeons at the 75th versus the 25th percentile of cranial specialization. In the spinal analysis cohort, each percentage-point increase in a surgeon's spinal specialization was associated with a 0.0122 reduction in the log odds of mortality (95% CI 0.0074-0.0170) and a 0.0058 reduction in the log odds of morbidity (95% CI 0.0049-0.0067). This resulted in a 26.8% difference in the predicted probability of mortality for neurosurgeons at the 75th versus the 25th percentile of spinal specialization. CONCLUSIONS For both spinal and cranial surgery patient cohorts derived from the NIS database, increased surgeon specialization was significantly and independently associated with improved mortality and morbidity rates, even after controlling for overall case volume.

Diabetes and Back Pain: Markers of Diabetes Disease Progression Are Associated With Chronic Back Pain.

IN BRIEF Diabetes has been associated with the incidence of back pain. However, the relationship between markers of diabetes progression and back pain has not been studied. The objective of this study was to correlate clinical and laboratory measures of diabetes disease severity to the presence of back pain to provide insight into the relationship between these conditions. Findings showed that markers of diabetes disease progression were associated with the presence of back pain, suggesting that uncontrolled diabetes may contribute to the development of chronic back pain.

Comprehensive biomechanical analysis of three reconstruction techniques following total sacrectomy: an in vitro human cadaveric model.

OBJECTIVE Aggressive sacral tumors often require en bloc resection and lumbopelvic reconstruction. Instrumentation failure and pseudarthrosis remain a clinical concern to be addressed. The objective in this study was to compare the biomechanical stability of 3 distinct techniques for sacral reconstruction in vitro. METHODS In a human cadaveric model study, 8 intact human lumbopelvic specimens (L2-pelvis) were tested for flexion-extension range of motion (ROM), lateral bending, and axial rotation with a custom-designed 6-df spine simulator as well as axial compression stiffness with the MTS 858 Bionix Test System. Biomechanical testing followed this sequence: 1) intact spine; 2) sacrectomy (no testing); 3) Model 1 (L3-5 transpedicular instrumentation plus spinal rods anchored to iliac screws); 4) Model 2 (addition of transiliac rod); and 5) Model 3 (removal of transiliac rod; addition of 2 spinal rods and 2 S-2 screws). Range of motion was measured at L4-5, L5-S1/cross-link, L5-right ilium, and L5-left ilium. RESULTS Flexion-extension ROM of the intact specimen at L4-5 (6.34° ± 2.57°) was significantly greater than in Model 1 (1.54° ± 0.94°), Model 2 (1.51° ± 1.01°), and Model 3 (0.72° ± 0.62°) (p < 0.001). Flexion-extension at both the L5-right ilium (2.95° ± 1.27°) and the L5-left ilium (2.87° ± 1.40°) for Model 3 was significantly less than the other 3 cohorts at the same level (p = 0.005 and p = 0.012, respectively). Compared with the intact condition, all 3 reconstruction groups statistically significantly decreased lateral bending ROM at all measured points. Axial rotation ROM at L4-5 for Model 1 (2.01° ± 1.39°), Model 2 (2.00° ± 1.52°), and Model 3 (1.15° ± 0.80°) was significantly lower than the intact condition (5.02° ± 2.90°) (p < 0.001). Moreover, axial rotation for the intact condition and Model 3 at L5-right ilium (2.64° ± 1.36° and 2.93° ± 1.68°, respectively) and L5-left ilium (2.58° ± 1.43° and 2.93° ± 1.71°, respectively) was significantly lower than for Model 1 and Model 2 at L5-right ilium (5.14° ± 2.48° and 4.95° ± 2.45°, respectively) (p = 0.036) and L5-left ilium (5.19° ± 2.34° and 4.99° ± 2.31°) (p = 0.022). Last, results of the axial compression testing at all measured points were not statistically different among reconstructions. CONCLUSIONS The addition of a transverse bar in Model 2 offered no biomechanical advantage. Although the implementation of 4 iliac screws and 4 rods conferred a definitive kinematic advantage in Model 3, that model was associated with significantly restricted lumbopelvic ROM.

Trends in Management of Intracranial Meningiomas: Analysis of 49,921 Cases from Modern Cohort.

OBJECTIVE: We sought to characterize patterns and treatment for intracranial meningiomas in the Surveillance, Epidemiology, and End Results set of cancer registries. METHODS: SEER data was queried from 2004-2012 for cases of intracranial meningioma using appropriate topography and histology codes. RESULTS: A total of 49,921 patients with intracranial meningioma were identified. The vast majority of cases were associated with a benign histology (n = 47,047, 94.2%). There were 21,145 patients (42.4%) who underwent surgical management, 2783 who received radiation alone (5.6%), and 25,993 who underwent surveillance only (52.1%). Surgical management decreased in frequency from 48.8% of all cases in 2004 to 38.3% of cases in 2012 (P < 0.001). Radiation alone remained stable over time with a range of 4.8%-6.3% of cases. Observation increased from 45.0% of cases in 2004 to 56.7% of cases in 2012 (P < 0.001). On unadjusted analysis, surgical management was associated with younger age and larger tumor size. The incidence of tumors <2 cm in size increased significantly over the study period from 29.7% in 2004 to 41.7% in 2012 (P < 0.001). After adjusting for tumor size, multivariable analysis demonstrated that the odds of observation as a primary management strategy were greater in 2012 relative to 2004 (odds ratio 1.33, 95% confidence interval 1.21-1.45). CONCLUSION: The incidence of intracranial meningiomas increased, while tumor size at the time of diagnosis decreased. Moreover, the number undergoing no treatment increased as a treatment strategy and was more likely employed for older patients, those of African-American race, and those with smaller tumors.

Predictors of Discharge to a Nonhome Facility in Patients Undergoing Lumbar Decompression Without Fusion for Degenerative Spine Disease.

BACKGROUND: Patients recovering from decompressive laminectomy without fusion may require assistance with activities of daily living and physical/occupational therapy upon hospital discharge. OBJECTIVE: To examine comorbidities and perioperative characteristics of patients undergoing lumbar decompression for associations with discharge status using a multicenter database. METHODS: A multicenter database was used for this retrospective cohort analysis. Patients admitted from home with degenerative spine disease for lumbar decompression without fusion were included. Thirty-day outcomes and operative characteristics were compared as a function of patient discharge using chi-square and Wilcoxon Rank Sum tests. Multivariable logistic regression was used to determine factors associated with discharge to a nonhome facility. RESULTS: Of the 8627 patients included for analysis, 9.7% were discharged to a nonhome facility. On multivariable analysis, age (85+ vs <65, odds ratio [OR] 13.59), number of levels of decompression (3+ vs 1, OR 1.75), African American race vs Non-Hispanic or Hispanic White (OR 1.87), female vs male gender (OR 1.97), body mass index (BMI) (40+ vs 18.5-24.9, OR 1.74), American Society of Anesthesiologists physical classification status (4 vs 1 or 2, OR 2.35), hypertension (OR 1.29), dependent functional status (OR 3.92), diabetes (OR 1.47), smoking (OR 1.40), hematocrit (<35 vs 35+, OR 1.76), international normalized ratio (≥1.3 vs <1.3, OR 2.32), and operative time (3+ h vs <1 h, OR 5.34) were significantly associated with an increased odds of discharge to nonhome facilities. CONCLUSION: Preoperative status and operative course variables can influence discharge disposition in lumbar decompression patients. Identifying specific factors that contribute to a greater likelihood of dismissal to skilled facility or rehabilitation unit can further inform both surgeons and patients during preoperative counseling and disposition planning.

Quantitative analysis of the effect of institutional case volume on complications after surgical clipping of unruptured aneurysms.

OBJECTIVE The mechanism by which greater institutional case volume translates into improved outcomes after surgical clipping of unruptured intracranial aneurysms (UIAs) is not well established. The authors thus aimed to assess the effect of case volume on the rate of various types of complications after clipping of UIAs. METHODS Using information on the outcomes of inpatient admissions for surgical clipping of UIAs collected within a national database, the relationship of institutional case volume to the incidence of different types of complications after clipping was investigated. Complications were subdivided into different categories, which included all complications, ischemic stroke, intracerebral hemorrhage, medical complications, infectious complications, complications related to anesthesia, and wound complications. The relationship of case volume to different types of complications was assessed using linear regression analysis. The relationships between case volume and overall complication and stroke rates were fit with both linear and quadratic equations. The numerical cutoff for institutional case volume above and below which the authors found the greatest differences in mean overall complication and stroke rate was determined using classification and regression tree (CART) analysis. RESULTS Between October 2012 and September 2015, 125 health care institutions reported patient outcomes from a total of 6040 cases of clipping of UIAs. On linear regression analysis, increasing case volume was negatively correlated to both overall complications (r2 = 0.046, p = 0.0234) and stroke (r2 = 0.029, p = 0.0557) rate, although the relationship of case volume to the complication (r2 = 0.092) and stroke (r2 = 0.067) rate was better fit with a quadratic equation. On CART analysis, the cutoff for the case number that yielded the greatest difference in overall complications and stroke rate between higher- or lower-volume centers was 6 cases/year and 3 cases/year, respectively. CONCLUSIONS Although the authors confirm that increasing case volume is associated with reduced complications after clipping of UIAs, their results suggest that the relationship between case volume and complications is not necessarily linear. Moreover, these results indicate that the effect of case volume on outcome is most evident between very-low-volume centers relative to centers with a medium-to-high volume.

Minimally Invasive Surgery Versus Open Surgery Spinal Fusion for Spondylolisthesis: A Systematic Review and Meta-analysis.

STUDY DESIGN: Systematic review and meta-analysis. OBJECTIVE: Compare minimally invasive surgery (MIS) and open surgery (OS) spinal fusion outcomes for the treatment of spondylolisthesis. SUMMARY OF BACKGROUND DATA: OS spinal fusion is an interventional option for patients with spinal disease who have failed conservative therapy. During the past decade, MIS approaches have increasingly been used, with potential benefits of reduced surgical trauma, postoperative pain, and length of hospital stay. However, current literature consists of single-center, low-quality studies with no review of approaches specific to spondylolisthesis only. METHODS: This first systematic review of the literature regarding MIS and OS spinal fusion for spondylolisthesis treatment was performed using the Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines for article identification, screening, eligibility, and inclusion. Electronic literature search of Medline/PubMed, Cochrane, EMBASE, and Scopus databases yielded 2489 articles. These articles were screened against established criteria for inclusion into this study. RESULTS: A total of five retrospective and five prospective articles with a total of 602 patients were found. Reported spondylolisthesis grades were I and II only. Overall, MIS was associated with less intraoperative blood loss (mean difference [MD], -331.04 mL; 95% confidence interval [CI], -490.48 to -171.59; P < 0.0001) and shorter length of hospital stay (MD, -1.74 days; 95% CI, -3.04 to -0.45; P = 0.008). There was no significant difference overall between MIS and OS in terms of functional or pain outcomes. Subgroup analysis of prospective studies revealed MIS had greater operative time (MD, 19.00 minutes; 95% CI, 0.90 to 37.10; P = 0.04) and lower final functional scores (weighted MD, -1.84; 95% CI, -3.61 to -0.07; P = 0.04) compared with OS. CONCLUSION: Current data suggests spinal fusion by MIS is a safe and effective approach to treat grade I and grade II spondylolisthesis. Moreover, although prospective trials associate MIS with better functional outcomes, longer-term and randomized trials are warranted to validate any association found in this study. LEVEL OF EVIDENCE: 2.

The Association between Psychiatric Comorbidities and Outcomes for Inpatients with Traumatic Brain Injury.

It is well established that traumatic brain injury (TBI) is associated with the development of psychiatric disorders. However, the impact of psychiatric disorders on TBI outcome is less well understood. We examined the outcomes of patients who experienced a traumatic subdural hemorrhage and whether a comorbid psychiatric disorder was associated with a change in outcome. A retrospective observational study was performed in the California Office of Statewide Health Planning and Development (OSHPD) and the Nationwide Inpatient Sample (NIS). Patients hospitalized for acute subdural hemorrhage were identified using International Classification of Diseases, Ninth Revision (ICD-9) diagnosis codes. Patients with coexisting psychiatric diagnoses were identified. Outcomes studied included mortality and adverse discharge disposition. In OSPHD, diagnoses of depression (OR = 0.64, p < 0.001), bipolar disorder (OR = 0.45, p < 0.05), and anxiety (OR = 0.37, p < 0.001) were associated with reduced mortality during hospitalization for TBI, with a trend toward psychosis (OR = 0.56, p = 0.08). Schizophrenia had no effect. Diagnoses of psychosis (OR = 2.12, p < 0.001) and schizophrenia (OR = 2.60, p < 0.001) were associated with increased adverse discharge. Depression and bipolar disorder had no effect, and anxiety was associated with reduced adverse discharge (OR = 0.73, p = 0.01). Results were confirmed using the NIS. Analysis revealed novel associations between coexisting psychiatric diagnoses and TBI outcomes, with some subgroups having decreased mortality and increased adverse discharge. Potential mechanisms include pharmacological effects of frequently prescribed psychiatric medications, the pathophysiology of individual psychiatric disorders, or under-coding of psychiatric illness in the most severely injured patients. Because pharmacological mechanisms, if validated, might lead to improved outcome in TBI patients, further studies may provide significant public health benefit.

Relationship of A1 segment hypoplasia to anterior communicating artery aneurysm morphology and risk factors for aneurysm formation.

OBJECTIVE Hypoplasia of the A1 segment of the anterior cerebral artery is frequently observed in patients with anterior communicating artery (ACoA) aneurysms. The effect of this anatomical variant on ACoA aneurysm morphology is not well understood. METHODS Digital subtraction angiography images were reviewed for 204 patients presenting to the authors' institution with either a ruptured or an unruptured ACoA aneurysm. The ratio of the width of the larger A1 segment to the smaller A1 segment was calculated. Patients with an A1 ratio greater than 2 were categorized as having A1 segment hypoplasia. The relationship of A1 segment hypoplasia to both patient and aneurysm characteristics was then assessed. RESULTS Of 204 patients that presented with an ACoA aneurysm, 34 (16.7%) were found to have a hypoplastic A1. Patients with A1 segment hypoplasia were less likely to have a history of smoking (44.1% vs 62.9%, p = 0.0410). ACoA aneurysms occurring in the setting of a hypoplastic A1 were also found to have a larger maximum diameter (mean 7.7 vs 6.0 mm, p = 0.0084). When considered as a continuous variable, increasing A1 ratio was associated with decreasing aneurysm dome-to-neck ratio (p = 0.0289). There was no significant difference in the prevalence of A1 segment hypoplasia between ruptured and unruptured aneurysms (18.9% vs 10.7%; p = 0.1605). CONCLUSIONS Our results suggest that a hypoplastic A1 may affect the morphology of ACoA aneurysms. In addition, the relative lack of traditional risk factors for aneurysm formation in patients with A1 segment hypoplasia argues for the importance of hemodynamic factors in the formation of ACoA aneurysms in this anatomical setting.

Complications, Readmissions, and Revisions for Spine Procedures Performed by Orthopedic Surgeons Versus Neurosurgeons: A Retrospective, Longitudinal Study.

STUDY DESIGN: Retrospective database analysis. OBJECTIVE: To examine the impact of training pathway, either neurosurgical or orthopedic, on complications, readmissions, and revisions in spine surgery. SUMMARY OF BACKGROUND DATA: Training pathway has been shown to have an impact on outcomes in various surgical subspecialties. Although training pathway has not been shown to have a significant impact on spine surgery outcomes in the perioperative period, long-term results are unknown. MATERIALS AND METHODS: A retrospective analysis of 197,682 patients receiving 1 of 3 common spine surgeries [lumbar laminectomy, lumbar fusion, and anterior cervical discectomy and fusion (ACDF)] between 2006 and 2010 was conducted. Patient data were obtained from a large claims database. Postoperative adverse effects, all-cause readmission, revision surgery rates, and intermediary payments in these cohorts of patients were compared between spine surgeons with either neurosurgical or orthopedic backgrounds. RESULTS: Patient demographics, hospital-stay characteristics, and medical comorbidities were similar between neurosurgeons and orthopedic surgeons. The risks of surgical complications, all-cause readmission, and revision surgery were also similar between neurosurgeons and orthopedic surgeons across all procedure types assessed, with several minor exceptions: neurosurgeons had marginally higher odds of any complication for lumbar fusions [odds ratio (OR) 1.14; 95% confidence interval (CI), 1.09-1.20] and ACDFs (OR, 1.09; 95% CI, 1.04-1.15). Neurosurgeons also had slightly higher rates of revision surgery for concurrent lumbar laminectomy with fusion (OR, 1.14; 95% CI, 1.08-1.22), and ACDFs (OR, 1.20; 95% CI, 1.14-1.28). No associations between surgeon type and any particular complication were consistently observed for all procedure groups. There were also no associations between surgeon type and 30-day all-cause readmission. Median total intermediary payments were somewhat higher for neurosurgery patients for all procedure groups assessed. CONCLUSIONS: Few significant associations between surgeon type and patient outcomes exist in the context of spine surgery. Those which do are small and unlikely to be clinically meaningful. LEVEL OF EVIDENCE: Level 3.

Hospital transfer associated with increased mortality after endovascular revascularization for acute ischemic stroke.

BACKGROUND: Patients with an acute ischemic stroke (AIS) due to large vessel occlusion often require transfer to an endovascular center for treatment. OBJECTIVE: To assess the effect of hospital transfer on outcomes after endovascular revascularization. METHODS: Outcomes of endovascular revascularization were compared between directly admitted and transferred patients using data from a national database and our own institution. RESULTS: 118 institutions within the database reported outcomes of 8533 inpatient admissions for endovascular treatment of AIS. Mortality rate (14.9% vs 18.6%; p=0.049) and mortality index (1.1 vs 1.6; p=0.048) were significantly lower among directly admitted patients than among transferred patients. Within our institutional cohort of 140 patients who underwent endovascular therapy, directly admitted patients had a significantly faster time to revascularization than transferred patients (277.4 vs 420.4 min; p≤0.0001). Among transferred patients, an increasing distance of transferred hospital to our home institution was associated with an increasing risk of mortality (unit OR=1.26, 95% CI 1.07 to 1.54; p=0.0061). CONCLUSIONS: Outcomes of revascularization may improve with methods to identify patients with large vessel occlusion before hospital admission, thus increasing the likelihood of initial triage to a comprehensive stroke center for patients eligible for endovascular intervention.

Discharge to a rehabilitation facility is associated with decreased 30-day readmission in elective spinal surgery.

The aim of our study was to determine independent predictors of discharge disposition to rehabilitation or skilled care (SC) facilities and investigate whether discharge location is associated with unplanned readmission and/or reoperation rates. All elective spinal surgery patients in a national surgical registry were analyzed using between 2011 and 2012. Multivariable logistic regression analysis was used to assess for predictors of discharge to rehabilitation or SC facilities versus home as well as to determine whether discharge disposition was significantly associated with the 30-day unplanned readmission or reoperation. Of 34,023 elective spinal surgery patients, the distribution of discharge locations was as follows: 30,606 (90.0%) discharged home, 1674 (4.9%) discharged to rehabilitation, and 1743 (5.1%) discharged to SC. Patients discharged home were associated with the lowest complication rate relative to rehabilitation and SC facilities. Following multivariable regression analysis, there was a significant increase in the odds of discharge to rehabilitation associated with age, male gender, current smoking, ASA class three and four, history of diabetes, operative time, total hospital length of stay, preoperative neurologic morbidity and having at least one postoperative morbidity event. Moreover, there were 804 (4.06%) 30-day unplanned readmissions and 822 (2.45%) unplanned reoperations. After risk adjustment, discharge to rehabilitation was independently associated with decreased odds of 30-day unplanned readmission (OR=0.41; p=0.008) but not reoperation.

Lumbar decompression in the elderly: increased age as a risk factor for complications and nonhome discharge.

OBJECTIVE With improving medical therapies for chronic conditions, elderly patients increasingly present as candidates for operative intervention for degenerative diseases of the spine. To date, there is a paucity of studies examining complications in lumbar decompression, without fusion, that include patients older than 80 years. Using a multicenter national database, the authors of this study evaluated lumbar decompression in the elderly, including octogenarians, to evaluate for associations between age and patient outcomes. METHODS The 2011-2013 American College of Surgeons' National Surgical Quality Improvement Program data set was queried for patients 65 years and older with diagnosis and procedure codes inclusive of degenerative spine disease and lumbar decompression without fusion. Morbidity and mortality within the 30-day postoperative period were the primary outcomes. Secondary outcomes of interest included unplanned readmission within 30 days or discharge to a nonhome facility. Outcomes and operative characteristics were compared using chi-square tests, Kruskal-Wallis tests, and multivariable logistic regression models. RESULTS A total of 8744 patients were identified; of these patients 4573 (52.30%) were 65 years and older. Elderly patients were stratified into 3 age categories: 85 years or older (n = 314), 75-84 years (n = 1663), and 65-74 years (n = 2596). Univariate analysis showed that, compared with age younger than 65 years, increased age was associated with the number of levels (≥ 3), readmissions within 30 days, nonhome discharge, any complication, length of stay, and blood transfusion (all p < 0.001). On multivariable analysis and with younger than 65 years as the reference, increased age was associated with any minor complication (p < 0.001; ≥ 85 years: OR 3.47, 95% CI 1.69-7.13; 75-84 years: OR 2.34, 95% CI 1.45-3.78; and 65-74 years: OR 1.44, 95% CI 0.94-2.20), as well as discharge location other than home (p < 0.001; ≥ 85 years: OR 13.59, 95% CI 9.47-19.49; 75-84 years: OR 5.64, 95% CI 4.33-7.34; and 65-74 years: OR 2.61, 95% CI 2.05-3.32). CONCLUSIONS The authors' high-powered, multicenter analysis of lumbar decompression without fusion in the elderly, specifically including patients older than 80 years, demonstrates that increased age is associated with more extensive operations, resulting in longer hospital stays, increased rates of nonhome discharge, and minor complications.

Risk factors for dural tears: a study of elective spine surgery.

OBJECTIVE: This study moves beyond previous cohort studies and benchmark data by studying a population of elective spine surgery from a multicenter registry in an effort to validate, disprove, and/or identify novel risk factors for dural tears. METHODS: A retrospective cohort analysis queried a multicenter registry for patients with degenerative spinal diagnoses undergoing elective spinal surgery from 2010-2014. Multivariable logistic regression analysis interrogated for independent risk factors of dural tears. RESULTS: Of 104,930 patients, a dural tear requiring repair occurred in 0.6% of cases. On adjusted analysis, the following factors were independently associated with increased likelihood of a dural tear: ankylosing spondylitis vs. intervertebral disc disorders, greater than two levels, combined surgical approach and posterior approach vs. anterior approach, decompression only vs. fusion and decompression, age groups 85+, 75-84 and 65-74 vs. <65, obesity (BMI ≥30), corticosteroid use and preoperative platelet count <150,000. CONCLUSIONS: This multicenter study identifies novel risk factors for dural tears in the elective spine surgery population, including corticosteroids, thrombocytopenia, and ankylosing spondylitis. The results of this analysis provide further information for surgeons to use both in operative planning and in preoperative counseling when discussing the risk of dural tears.

Predictors of 30-day perioperative morbidity and mortality of unruptured intracranial aneurysm surgery.

INTRODUCTION: Large-scale studies examining the incidence and predictors of perioperative complications after surgical clipping of unruptured intracranial aneurysms (UIA) using nationally representative prospectively collected data are lacking in the literature. METHODS: Using the American College of Surgeons' National Surgical Quality Improvement Program (ACS-NSQIP) dataset, we conducted a retrospective analysis of the complications experienced by patients that underwent surgical management of a UIA between the years of 2007 and 2013. The primary outcomes of interest were mortality within the 30-day perioperative period and adverse discharge disposition to a location other than home. Predictors of morbidity and mortality were elucidated using multivariable logistic regression analyses controlling for available patient demographic, comorbidity, and operative characteristics. RESULTS: 662 patients were identified in the ACS-NSQIP dataset for operative management of an unruptured aneurysm. The observed rates of 30-day mortality and adverse discharge disposition were 2.27% and 19.47%, respectively. A hundred and eight (16.31%) patients developed at least one major complication. On multivariable analysis, death within 30days was significantly associated with increased operative time (OR 1.005 per minute, 95% CI 1.002-1.008) and chronic preoperative corticosteroid use (OR 28.4, 95% CI 1.68-480.42), whereas major complication development was associated with increased operative time (OR 1.004 per minute, 95% CI 1.002-1.006), age (OR 1.017 per year, 95% CI 1-1.034), preoperative dependency (OR 3.3, 95% CI 1.16-9.40) and diabetes mellitus (OR 2.89, 95% CI 1.45-5.75). Lastly, increasing age (OR 1.017 per year, 95% CI 1-1.034) as well as ASA Class 3 (OR 1.73, 95% CI 1.08-2.77) and 4 (OR 2.28, 95% CI 1.1-4.72) were independent predictors of discharge to a location other than home. CONCLUSION: Our study yields morbidity and mortality benchmarks for UIA surgery in a representative, national surgical registry. It will hopefully aid in recognizing those patients at greater risk for postoperative complications following surgical management, leading to appropriate changes in treatment strategies for this selected group of patients.