An Objective and Reliable Method for Identifying Sarcopenia in Lumbar Spine Surgery Patients: Using Morphometric Measurements on Computed Tomography Imaging.

STUDY DESIGN: A retrospective observational study. PURPOSE: Establish a quantifiable and reproducible measure of sarcopenia in patients undergoing lumbar spine surgery based on morphometric measurements from readily available preoperative computed tomography (CT) imaging. OVERVIEW OF LITERATURE: Sarcopenia-the loss of skeletal muscle mass-has been linked with poor outcomes in several surgical disciplines; however, a reliable and quantifiable measure of sarcopenia for future assessment of outcomes in spinal surgery patients has not been established. METHODS: A cohort of 90 lumbar spine fusion patients were compared with 295 young, healthy patients obtained from a trauma da¬tabase. Cross-sectional vertebral body (VB) area, as well as the areas of the psoas and paravertebral muscles at mid-point of pedicles at L3 and L4 for both cohorts, was measured using axial CT imaging. Total muscle area-to-VB area ratio was calculated along with intraclass correlation coefficients for interobserver and intraobserver reliability. Finally, T-scores were calculated to help identify those patients with considerably diminished muscle-to-VB area ratios. RESULTS: Both muscle mass and VB areas were considerably larger in males compared with those in females, and the ratio of these two measures was not enough to account for large differences. Thus, a gender-based comparison was made between spine patients and healthy control patients to establish T-scores that would help identify those patients with sarcopenia. The ratio for paravertebral muscle area-to-VB area at the L4 level was the only measure with good interobserver reliability, whereas the other three of the four ratios were moderate. All measurements had excellent correlations for intraobserver reliability. CONCLUSIONS: We postulate that a patient with a T-score <-1 for total paravertebral muscle area-to-VB area ratio at the L4 level is the most reliable method of all our measurements that can be used to diagnose a patient undergoing lumbar spine surgery with sarcopenia.

Ischemic Optic Neuropathy Following Spine Surgery: Case Control Analysis and Systematic Review of the Literature.

STUDY DESIGN: Case-control analysis and systematic literature review. OBJECTIVE: To illustrate the prognosis and perioperative risk factors associated with this condition. SUMMARY OF BACKGROUND DATA: Ischemic optic neuropathy (ION) is the most common pathological diagnosis underlying postoperative vision loss. It comes in two primary forms-anterior (AION)-affecting the optic disc or posterior (PION) affecting the optic nerve proximal to the disc. Spine surgery remains one of the largest sources of acute perioperative visual loss. METHODS: We performed a 1:4 case-control analysis (by age and year of surgery) for patients with ION and those who didn't develop ION following spine surgery at our institution. A systematic literature search of Medline, Embase, Scopus from inception to September 2017 as also performed. RESULTS: We identified 12 cases from our institution. Comparison to 48 matched controls revealed fusion, higher number of operative levels, blood loss, and change in hemoglobin, hematocrit to be significantly associated with ION. Majority were diagnosed with PION (83%, 10/12) and had bilateral presentation (75%, 9/12). Only 30% patients (3/10) demonstrated improvement in visual acuity while the rest remained either unchanged (40%, 4/10) or worsened (20%, 2/10) at last follow-up. Literature review identified 182 cases from 42 studies. Posterior ischemic optic neuropathy (PION) was found in 58.7% (114/194) of cases, anterior ischemic optic neuropathy (AION) in 17% (33/19) and unspecified ION in 24% (47/194). PION was associated with higher odds of severe visual deficit at immediate presentation (odds ratio [OR]: 6.45, confidence interval [CI]: 1.04-54.3, P = 0.04) and last follow-up. CONCLUSION: PION is the most common cause of vision loss following spine surgery and causes more severe visual deficits compared with AION. Prone spine surgery especially multi-level fusions with longer operative time, higher blood loss, and intraoperative hypotension are most associated with the development of this devastating complication. LEVEL OF EVIDENCE: 3.

Assessing the Performance of National Surgical Quality Improvement Program Surgical Risk Calculator in Elective Spine Surgery: Insights from Patients Undergoing Single-Level Posterior Lumbar Fusion.

INTRODUCTION: The American College of Surgeons-National Surgical Quality Improvement Program Surgical Risk Calculator is a tool developed to use 21 individual patient characteristics to make predictions for occurrence of 13 general and 2 procedure-specific outcomes. The goal of this study was to evaluate the performance of the Surgical Risk Calculator in predicting outcomes in patients receiving posterior lumbar fusion. METHODS: American College of Surgeons-National Surgical Quality Improvement Program Participant Use File for 2015 was queried for patients with age ≥18 years undergoing single-level posterior lumbar fusion (PLF) surgery. Individual patient characteristics were entered into the online risk calculator interface to retrieve the predicted estimated risk for perioperative outcomes and complications. Following this, predictive performance was analyzed by computing Brier score, c-statistic, and sensitivity values for all observed outcomes. RESULTS: A total of 2808 patients undergoing single-level PLF were included in the analysis. Overall, a very low incidence of 30-day postoperative complications was observed with the procedure (0.9%-6.3%). Poor predictive performance was found for all outcomes, including readmissions (c-statistic = 0.63; sensitivity = 15.28%; Brier score = 0.048) and returns to operating room (c-statistic = 0.56; sensitivity = 21.05%; Brier score = 0.032). The best performance was observed for venous thromboembolism (c-statistic=0.66: Brier score = 0.008), although sensitivity was poor (3.85%) on account of low incidence. Predictive performance for length of stay revealed good agreement between observed and predicted values with the exception of prolonged predicted hospital stays (>3.5 days). CONCLUSIONS: This study assesses the performance of the risk calculator for a homogenous population of patients undergoing a single-level PLF. Although the calculator did not fare well in predicting most outcomes, results need to be interpreted in the context of the low incidence rate of such outcomes.

Impact of obesity on outcomes following lumbar spine surgery: A systematic review and meta-analysis.

The influence of obesity on spine surgery outcomes is highly controversial with a current clinical equipoise. Several studies suggest higher perioperative morbidity with obesity while other studies suggest otherwise. To address this gap in the literature, we conducted a systematic review and meta-analysis in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines with the objective of better defining the impact of obesity on outcomes following lumbar spine surgery. Risk of bias assessment was performed using the Newcastle-Ottawa Scale. Strength of evidence was assessed using the Grades of Recommendation, Assessment, Development and Evaluation (GRADE) Working Group system. Surgical outcomes such as blood loss, operative time, length of stay, complication and reoperation rates and functional outcomes represented by the change in Oswestry Disability Index and Visual Analog Scale-Back Pain were compared between obese and non-obese patients. A total of 32 studies with 23,415 patients were analyzed. Obese patients had slightly higher surgical blood loss (Mean Difference [MD]: 46.15 ml, CI: 20.21-72, p-value< .001, I2 = 85%) and longer operative times (MD: 17.17 min, CI: 9.91-24.43, p-value< .001, I2 = 95%), but similar length of stay as compared to non-obese patients. Higher complication (OR = 1.34, C.I. = 1.13-1.58, p = 0.01, I2 = 45%) and reoperation rates (OR = 1.40, C.I. = 1.19-1.64, p < 0.001, I2 = 20) were observed in obese patients. The differences, however, were not significant for obese patients undergoing MIS surgery. Functional outcomes (change in ODI and VAS-BP) were similar between the two groups. Overall confidence in GRADE estimates was either low or very low for all outcomes. Obesity might be linked to higher adverse events following lumbar spine surgery. Minimally invasive spine surgery, however, might offer comparable outcomes between obese and non-obese patients. However, further studies are needed to evaluate whether these findings remain valid for morbidly obese (BMI > 40) patients as well.

Endoscopic versus open approach in craniosynostosis repair: a systematic review and meta-analysis of perioperative outcomes.

INTRODUCTION: Surgery for craniosynostosis remains a crucial element in successful management. Intervention by both endoscopic and open approaches has been proven effective. Given the differences in timing and indications for these procedures, differences in perioperative outcomes have yet to be thoroughly compared between the two approaches. The aim of the systematic review and meta-analysis was to assess the available evidence of perioperative outcomes between the two approaches in order to better influence the management paradigm of craniosynostosis. METHODS: We followed recommended PRISMA guidelines for systematic reviews. Seven electronic databases were searched to identify all potentially relevant studies published from inception to February 2018 which were then screened against a set of selection criteria. Data were extracted and analyzed using meta-analysis of proportions. RESULTS: Twelve studies satisfied all the selection criteria to be included, which described a pooled cohort involving 2064 craniosynostosis patients, with 965 (47%) and 1099 (53%) patients undergoing surgery by endoscopic and open approaches respectively. When compared to the open approach, it was found that the endoscopic approach conferred statistically significant reductions in blood loss (MD = 162.4 mL), operative time (MD = 112.38 min), length of stay (MD = 2.56 days), and rates of perioperative complications (OR = 0.58), reoperation (OR = 0.37) and transfusion (OR = 0.09), where all p < 0.001. CONCLUSION: Both endoscopic and open approaches for the surgical management of craniosynostosis are viable considerations. The endoscopic approach confers a significant reduction in operative and postoperative morbidity when compared to the open approach. Given that specific indications for either approach should be considered when managing a patient, the difference in perioperative outcomes remain an important element of this paradigm. Future studies will validate the findings of this study and consider long-term outcomes, which will all contribute to rigor of craniosynostosis management.

Subthalamic and Pallidal Deep Brain Stimulation for Parkinson's Disease.

Deep brain stimulation (DBS) is a surgical treatment in which stimulation electrodes are permanently implanted in basal ganglia to treat motor fluctuations and symptoms of Parkinson's disease (PD). Subthalamic nucleus (STN) and globus pallidus internus (GPi) are the commonly used targets for DBS in PD. Many studies have compared motor and non-motor outcomes of DBS in both targets. However, the selection of PD patients for DBS targets is still poorly studied. Therefore, we performed this narrative review to summarize published studies comparing STN DBS and GPi DBS. GPi DBS is better for patients with problems in speech, mood, or cognition while STN DBS is better from an economic point of view as it allows much reduction in antiparkinson medications and less battery consumption.

Anterior versus posterior approaches for thoracic disc herniation: Association with postoperative complications.

OBJECTIVE: Thoracic disc herniations (TDH) represent 1.5-4% of all intervertebral disc herniations. Surgical treatment can be divided into anterior, lateral and posterior approaches and is an area of contention in the literature. Available evidence consists mostly of single-arm, single-institutional studies with limited sample sizes. The objective of this study is to investigate 30-day surgical outcomes following excision of TDH utilizing a national surgical registry. PATIENTS AND METHODS: The American College of Surgeons - National Surgical Quality Improvement Program (ACS-NSQIP) was queried for cases that underwent anterior (thoracotomy or thoracoscopy), lateral (extracavitary or costotransversectomy) or posterior (transpedicular or laminectomy) surgery for a primary diagnosis of TDH between 2012 and 2015. RESULTS: A total of 388 patients (48% females) were included in the analysis. An anterior approach was used in 65 patients, lateral approach in 34, transpedicular approach in 90 and laminectomy in 199. Overall, baseline demographics and clinical characteristics were similarly distributed between the four procedure groups. Patients undergoing an anterior approach spent, on average, 2-3 more days in the hospital compared to the other groups (p < .001). Furthermore, they were more likely to have developed a major complication (27%) compared to the lateral (8%), transpedicular (18%) or laminectomy group (14%) (p = .13). Unplanned 30-day readmission and return to the operating room occurred in 5-8% of patients (p = .69 and 0.63, respectively). Lastly, the majority of the patients were discharged to home or a home facility (anterior-74%; lateral-81%; transpedicular-68% and laminectomy-74%, p = .58). CONCLUSION: Anterior approaches had longer LOS and higher, although not statistically significant, complication rates. No difference was found with regard to discharge disposition. In light of these findings, surgeons should weigh the risks and benefits of each surgical technique during tailoring of decision making.