Victor M. Lu

Full-endoscopic versus micro-endoscopic and open discectomy: A systematic review and meta-analysis of outcomes and complications

OBJECTIVES The purpose of this study was to systematically compare the effectiveness and safety of full-endoscopic discectomy (FED) and micro-endoscopic discectomy (MED) with open discectomy (OD) for the treatment of symptomatic lumbar disc herniation. METHODS Electronic searches were performed using six databases from their inception to February 2016, identifying all relevant randomized controlled trials and comparative observational studies comparing either FED or MED with OD. Data were extracted and analyzed according to predefined clinical endpoints. RESULTS Twenty three studies were selected for analysis, including 421 FED, 6914 MED, and 21,152 OD cases. No significant difference was found between FED and OD in regards to postoperative visual analog scale (VAS) leg pain scores (WMD 0.03, P=0.93). Similar results were obtained for MED vs OD (WMD 0.09, P=0.18). In terms of postoperative Oswestry disability index (ODI), both FED and MED were similar to OD (WMD -2.60, P=0.32 and WMD -1.00, P=0.21, respectively). FED had a significantly shorter operative duration compared to OD (54.6 vs 102.6min, P=0.0001). MED alone and endoscopic approaches overall (including MED and FED) demonstrated significantly lower estimated blood loss (44.3 vs 194.4mL, P=0.03 and 38.2 vs 203.5mL, respectively, both p<0.05). FED alone demonstrated a trend towards lower estimated blood loss in comparison to OD (3.3 vs 244.9mL, P=0.07). No difference was found in overall complications, recurrence or reoperation rates, dural tears, root injury, wound infections, and spondylodiscitis between FED vs OD, or MED vs OD. CONCLUSIONS Based on this meta-analysis, FED and MED appear to be safe and efficacious alternatives to traditional approaches, but these results require further investigation and validation by prospective randomized studies.

Posterolateral Fusion Versus Interbody Fusion for Degenerative Spondylolisthesis: Systematic Review and Meta-Analysis:

Study Design: Systematic review and meta-analysis. Objective: Current surgical management of degenerative spondylolisthesis (DS) involves decompression of the spinal canal followed by fusion with or without interbody. The additional functional and operative benefits derived from interbody inclusion has yet to be thoroughly established with a number of recent studies producing conflicting results. Thus, we aim to compare the functional and operative outcomes after fusion against interbody fusion in the treatment of DS. Methods: This systematic review of the literature comparing posterolateral fusion (PLF) and posterior lumbar interbody fusion (PLIF) outcomes in the treatment of DS was performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Electronic searches of 6 databases yielded 386 articles from database inception to July 2016, which were screening against established criteria for inclusion into this study. Results: A total of 6 studies, satisfied criteria and reported outcomes for 721 patients. Fusion alone was performed in 458 (63.5%) patients and interbody fusion was performed in 263 (36.5%) patients. Functional outcomes Oswestry Disability Index (P = .29) and visual analog scale (P = .13) were not statistically different between the 2 approaches. Furthermore, there was no significant inferiority between fusion alone and with interbody in terms of the operative outcomes of blood loss (P = .38), reoperation rate (P = .66), hospital stay (P = .96), complication rate (P = .78), or fusion rate (P = .15). Conclusions: There was no statistically significant difference in functional and operative outcomes following fusion alone versus with interbody. Additional subgroup analysis of intrinsic DS features in future large, prospective, randomized controlled trials will improve the validity of these findings.

Older studies can underestimate prognosis of glioblastoma biomarker in meta-analyses: a meta-epidemiological study for study-level effect in the current literature

IntroductionThere are many potential biomarkers in glioblastoma (GBM), and meta-analyses represent the highest level of evidence when inferring their prognostic significance. It is possible however, that inherent design properties of the studies included in these meta-analyses may affect the pooled hazard ratio (HR) of the meta-analyses. This meta-epidemiological study aims to investigate the potential bias of three study-level properties in meta-analyses of GBM biomarkers currently published in the literature.MethodsSeven electronic databases from inception to December 2017 were searched for meta-analyses evaluating different GBM biomarkers, which were screened against specific criteria. Study-level data were extracted from each meta-analysis, and analyzed using logistic regression to yield the ratio of HR (RHR) summary statistic.ResultsNine meta-analyses investigating different GBM biomarkers were included. Of all the meta-analyses, the HRs of two studies were significantly underestimated by older studies; they investigated biomarkers IDH1 (RHR = 1.145; p = 0.017) and CD133 (RHR = 0.850; p = 0.013). Study-level size and design showed non-significant trends towards affecting the overall HR in all included meta-analyses.ConclusionsThis meta-epidemiological study demonstrated that study-level year can already significantly affect the pooled HR of GBM biomarkers reported by meta-analyses. It is possible that in the future, more study-level properties will exert significant effect. In terms of future GBM biomarker meta-analyses, special consideration of bias should be given to these study-level properties as potential sources of effect on the prognostic pooled HR.

Quantifying the prognostic significance in glioblastoma of seizure history at initial presentation: A systematic review and meta-analysis ☆

The role of prognostic factors in the management of glioblastoma (GBM) is very important given the stasis in improving its clinical outcomes. Patients who initially present with a positive seizure history at diagnosis have anecdotally experienced superior survival outcomes. The aim of this review was to perform a systematic review and meta-analysis to quantify the potential prognostic significance of positive seizure history in GBM patients. A search strategy was performed using the PRISMA guidelines for article identification, screening, eligibility and inclusion. Relevant articles were identified from six electronic databases from their inception to August 2017. These articles were screened against established criteria for inclusion into this study. Meta-analysis was conducted by pooling results with multivariate-adjusted hazard ratios (HRs). After screening, 6 relevant studies were included for analysis. There was a total cohort of 1836 GBM patients, of which 488 (27%) had a positive seizure history at initial presentation. There was a significant association found between positive seizure history in GBM patients and less mortality events, with an overall HR of 0.71 (95%CI=0.63-0.81, p<0.00001, I2=4%). Positive seizure history at initial presentation of GBM can be associated with improved prognosis. However, there are a number of variables that need to be considered further, including genetic profiling, lead time bias, and anti-epileptic drug (AED) therapy. This review represents the highest level of evidence to date, and its result will be validated by future, prospective study of larger cohorts.

Comparison of operative outcomes of eloquent glioma resection performed under awake versus general anesthesia: A systematic review and meta-analysis

Surgical resection of eloquent glioma can be achieved under general anesthesia (GA) or awake anesthesia (AA). The appeal of AA is that it facilitates intraoperative identification and avoidance of eloquent areas, which has the potential to minimize functional compromise. The aim of this meta-analysis was to compare the operative outcomes of eloquent glioma resection performed under GA compared to AA to assist in optimizing the decision algorithm between the two approaches. Searches of seven electronic databases from inception to December 2017 were conducted following Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. There were 1037 articles identified for screening. Data were extracted and analyzed using meta-analysis of proportions. A total of 9 comparative studies were included for analysis. Resection of glioma involving eloquent areas achieved under AA is mostly comparable in terms of operative and functional outcomes to that of GA. AA did demonstrate significantly lower incidence of postoperative nausea and vomiting (PONV, OR, 0.17; p < 0.001) and shorter length of stay (LOS, MD, -1.76 days; p = 0.02) when compared to GA. Future studies that are larger, prospective, randomized, and include long term quality of life metrics will assist in elucidating the true clinical benefit of AA in resecting glioma involving eloquent areas. This will assist in further developing management protocol of these glioma.

Realizing the therapeutic potential of rare earth elements in designing nanoparticles to target and treat glioblastoma.

The prognosis of brain cancer glioblastoma (GBM) is poor, and despite intense research, there have been no significant improvements within the last decade. This stasis implicates the need for more novel therapeutic investigation. One such option is the use of nanoparticles (NPs), which can be beneficial due to their ability to penetrate the brain, overcome the blood-brain barrier and take advantage of the enhanced permeation and retention effect of GBM to improve specificity. Rare earth elements possess a number of interesting natural properties due to their unique electronic configuration, which may prove therapeutically advantageous in an NP formulation. The underexplored exciting potential for rare earth elements to augment the therapeutic potential of NPs in GBM treatment is discussed in this review.

The current evidence of statin use affecting glioblastoma prognosis

Cholesterol-lowering statins have been postulated to improve cancer outcomes by many unconfirmed mechanisms. The prognosis of glioblastoma (GBM) remains dismal, and there is a paucity of evidence regarding the potential for preoperative statins to exert a benefit upon prognosis. In light of a recent report, the current evidence in the literature regarding statin use affecting GBM prognosis is discussed.

Magnetic Resonance guided Laser Interstitial Thermal Therapy (MRgLITT) vs Stereotactic Radiosurgery (SRS) for Medically Intractable Temporal Lobe Epilepsy (TLE) : A Systematic Review and Meta-Analysis of Seizure Outcomes and Complications

INTRODUCTION Magnetic resonance-guided laser interstitial thermal therapy (MRgLITT) and stereotactic radiosurgery (SRS) are 2 emerging minimally invasive procedures being increasingly used for surgical intervention in cases of medically intractable temporal lobe epilepsy (TLE). To date, no comparative analyses of these 2 procedures have been made. In the current study, we synthesized pooled data from existing studies in an attempt to present a systematic review and meta-analysis of seizure and clinical outcomes of the 2 procedures in patients with TLE. METHODS The Population, Intervention, Comparator, and Outcome (PICO) approach and Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines were followed to perform an indirect meta-analysis of seizure and clinical outcomes between MRgLITT and SRS. Only studies reporting outcomes for patients with TLE were included in the current review. RESULTS A total of 19 studies were included in the final analysis, giving a total of 415 TLE patients. Of those studies, 9 were on MRgLITT, with a total of 250 patients (60%), and 10 were on SRS, with a total of 165 patients (40%). We found that the overall seizure freedom rate was comparable between the 2 procedures (MRgLITT 50%, 95% confidence interval [CI] 44% to 56%, vs. SRS 42%, 95% CI 27% to 59%, P = 0.39). Similarly, among patients with lesional pathologic conditions only, the seizure freedom rate was comparable between the 2 procedures (MRgLITT 62%, 95% CI 48% to 74%, vs. SRS 50%, 95% CI 37% to 64%, P = 0.23). Compared with SRS, MRgLITT was associated with lower complication rates (MRgLITT 20%, 95% CI 14% to 26% vs. SRS 32%, 95% CI 20% to 46%, P = 0.06) but similar reoperation rates (15%, 95% CI 9% to 22% vs. 27%, 95% CI 12% to 46%, P = 0.31). CONCLUSIONS As minimally invasive procedures continue to gain popularity for use in surgery for epilepsy, it is imperative to evaluate their efficacy and safety outcomes. In this study we pooled the data from existing studies to compare the seizure and clinical outcomes in patients with TLE undergoing MRgLITT and SRS. We found similar outcomes and complications between the 2 procedures.

Glossopharyngeal Neuralgia Treatment Outcomes After Nerve Section, Microvascular Decompression, or Stereotactic Radiosurgery: A Systematic Review and Meta-Analysis

BACKGROUND Glossopharyngeal neuralgia (GPN) is a rare neuralgic pain syndrome amenable to neurosurgical treatments, including nerve section (NS), microvascular decompression (MVD), and stereotactic radiosurgery (SRS). However, thorough comparisons of the modalities have not been performed to date. The objective of the present study was to compare the pain and complication outcomes after these approaches to GPN. METHODS Searches of 7 electronic databases from inception to June 2018 were conducted following the appropriate guidelines. The incidence rates (IRs) of short-term (≤3 months) and long-term (≥12 months) pain relief and complications were extracted and analyzed using a meta-analysis. Meta-regression was used to assess for heterogeneity. RESULTS A total of 792 GPN cases managed by NS, MVD, or SRS were described by 6, 11, and 6 studies, reporting outcomes for 282 (36%), 446 (56%), and 67 (8%) cases. The short-term pain relief rate was highest after NS postoperatively (IR, 94%; 95% confidence interval [CI], 88%-98%) and lowest after SRS at 3 months postoperatively (IR, 80%; 95% CI, 68%-96%). The postoperative complication rate was greatest after MVD (IR, 26%; 95% CI, 16%-38%) and lowest after SRS (IR, 0%; 95% CI, 0%-4%). The long-term pain relief rate was greatest after NS (IR, 96%; 95% CI, 91%-99%) and lowest after SRS (IR, 82%; 95% CI, 67%-94%). Statistically significant differences between the approaches were found for each outcome. CONCLUSION Neurosurgical treatment of GPN is frequently performed by 1 of 3 modalities with unique outcomes profiles. NS might provide the most favorable treatment response, with respect to short- and long-term pain relief and postoperative outcomes.

Olfactory groove and tuberculum sellae meningioma resection by endoscopic endonasal approach versus transcranial approach: A systematic review and meta-analysis of comparative studies

Intracranial meningiomas such as olfactory groove meningioma (OGM) and tuberculum sellae meningioma (TSM) arising at the anterior skull base are amenable to surgical resection. Traditionally, this has been achieved by transcranial approaches (TCAs), however, there has been an evolution in an endoscopic endonasal approach (EEA) within recent years. The aim of this systematic review and meta-analysis was to determine if the EEA was superior to the TCA in managing these anterior skull base meningioma based on comparative studies only, and highlight the limitations of the current literature. Searches of seven electronic databases from inception to April 2018 were conducted following Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. There were 1479 articles identified for screening. Data were extracted and analyzed using meta-analysis of proportions. A total of 10 comparative studies satisfied criteria for inclusions. Resection by the EEA resulted in significantly less likelihood of worse vision (OR, 0.318; p = 0.039) when compared to TCA in OGM. However, EEA resulted also in significantly greater likelihoods of olfactory loss in OGM (OR, 4.511; p = 0.038) and TSM (OR, 3.075; p = 0.017), and CSF leak (OR, 3.854; p = 0.013) in TSM. In terms of surgical and prognosis outcomes, there was no statistically significant trend in favor of either approach in OGM or TSM. The EEA appears to confer a different postoperative complication profile when compared to the TCA in resecting OGM vs TSM which validates previous case-series comparisons. There is a need for longer-term studies that are larger, prospective, randomized in order to fully elucidate efficacy given slow tendency for progression of meningioma in order to develop a more rigorous approach selection algorithm.