Alireza Mansouri

Anterior Cervical Discectomy with Arthroplasty versus Arthrodesis for Single-Level Cervical Spondylosis: A Systematic Review and Meta-Analysis

Objective To estimate the effectiveness of anterior cervical discectomy with arthroplasty (ACDA) compared to anterior cervical discectomy with fusion (ACDF) for patient-important outcomes for single-level cervical spondylosis. Data sources Electronic databases (MEDLINE, EMBASE, Cochrane Register for Randomized Controlled Trials, BIOSIS and LILACS), archives of spine meetings and bibliographies of relevant articles. Study selection We included RCTs of ACDF versus ACDA in adult patients with single-level cervical spondylosis reporting at least one of the following outcomes: functionality, neurological success, neck pain, arm pain, quality of life, surgery for adjacent level degeneration (ALD), reoperation and dysphonia/dysphagia. We used no language restrictions. We performed title and abstract screening and full text screening independently and in duplicate. Data synthesis We used random-effects model to pool data using mean difference (MD) for continuous outcomes and relative risk (RR) for dichotomous outcomes. We used GRADE to evaluate the quality of evidence for each outcome. Results Of 2804 citations, 9 articles reporting on 9 trials (1778 participants) were eligible. ACDA is associated with a clinically significant lower incidence of neurologic failure (RR  = 0.53, 95% CI  = 0.37–0.75, p = 0.0004) and improvement in the Neck pain visual analogue scale (VAS) (MD  = 6.56, 95% CI  = 3.22–9.90, p = 0.0001; Minimal clinically important difference (MCID)  = 2.5. ACDA is associated with a statistically but not clinically significant improvement in Arm pain VAS and SF-36 physical component summary. ACDA is associated with non-statistically significant higher improvement in the Neck Disability Index Score and lower incidence of ALD requiring surgery, reoperation, and dysphagia/dysphonia. Conclusions There is no strong evidence to support the routine use of ACDA over ACDF in single-level cervical spondylosis. Current trials lack long-term data required to assess safety as well as surgery for ALD. We suggest that ACDA in patients with single level cervical spondylosis is an option although its benefits and indication over ACDF remain in question.

Predictors of seizure outcomes in children with tuberous sclerosis complex and intractable epilepsy undergoing resective epilepsy surgery: an individual participant data meta-analysis.

Objective To perform a systematic review and individual participant data meta-analysis to identify preoperative factors associated with a good seizure outcome in children with Tuberous Sclerosis Complex undergoing resective epilepsy surgery. Data Sources Electronic databases (MEDLINE, EMBASE, CINAHL and Web of Science), archives of major epilepsy and neurosurgery meetings, and bibliographies of relevant articles, with no language or date restrictions. Study Selection We included case-control or cohort studies of consecutive participants undergoing resective epilepsy surgery that reported seizure outcomes. We performed title and abstract and full text screening independently and in duplicate. We resolved disagreements through discussion. Data Extraction One author performed data extraction which was verified by a second author using predefined data fields including study quality assessment using a risk of bias instrument we developed. We recorded all preoperative factors that may plausibly predict seizure outcomes. Data Synthesis To identify predictors of a good seizure outcome (i.e. Engel Class I or II) we used logistic regression adjusting for length of follow-up for each preoperative variable. Results Of 9863 citations, 20 articles reporting on 181 participants were eligible. Good seizure outcomes were observed in 126 (69%) participants (Engel Class I: 102(56%); Engel class II: 24(13%)). In univariable analyses, absence of generalized seizure semiology (OR = 3.1, 95%CI = 1.2–8.2, p = 0.022), no or mild developmental delay (OR = 7.3, 95%CI = 2.1–24.7, p = 0.001), unifocal ictal scalp electroencephalographic (EEG) abnormality (OR = 3.2, 95%CI = 1.4–7.6, p = 0.008) and EEG/Magnetic resonance imaging concordance (OR = 4.9, 95%CI = 1.8–13.5, p = 0.002) were associated with a good postoperative seizure outcome. Conclusions Small retrospective cohort studies are inherently prone to bias, some of which are overcome using individual participant data. The best available evidence suggests four preoperative factors predictive of good seizure outcomes following resective epilepsy surgery. Large long-term prospective multicenter observational studies are required to further evaluate the risk factors identified in this review.

Neurocognitive and Seizure Outcomes of Selective Amygdalohippocampectomy versus Anterior Temporal Lobectomy for Mesial Temporal Lobe Epilepsy

Objective. To report our institutional seizure and neuropsychological outcomes for a series of patients with mesial temporal lobe epilepsy (mTLE) undergoing anterior temporal lobectomy (ATL) or selective amygdalohippocampectomy (SelAH) between 2004 and 2011. Methods. A retrospective study of patients with mTLE was conducted. Seizure outcome was reported using time-to-event analysis. Cognitive outcome was reported using the change principal in component factor scores, one each, for intellectual abilities, visuospatial memory, and verbal memory. The Boston Naming Test was used for naming assessment. Language dominant and nondominant resections were compared separately. Students t-test was used to assess statistical significance. Results. Ninety-six patients (75 ATL, 21 SelAH) were included; fifty-four had complete neuropsychological follow-up. Median follow-up was 40.5 months. There was no statistically significant difference in seizure freedom or any of the neuropsychological outcomes, although there was a trend toward greater postoperative decline in naming in the dominant hemisphere group following ATL. Conclusion. Seizure and neuropsychological outcomes did not differ for the two surgical approaches which is similar to most prior studies. Given the theoretical possibility of SelAH sparing language function in patients with epilepsy secondary to mesial temporal sclerosis and the limited high-quality evidence creating equipoise, a multicenter randomized clinical trial is warranted.

High-definition fiber tractography for the evaluation of perilesional white matter tracts in high-grade glioma surgery

Conventional white matter (WM) imaging approaches, such as diffusion tensor imaging (DTI), have been used to preoperatively identify the location of affected WM tracts in patients with intracranial tumors in order to maximize the extent of resection and potentially reduce postoperative morbidity. DTI, however, has limitations that include its inability to resolve multiple crossing fibers and its susceptibility to partial volume effects. Therefore, recent focus has shifted to more advanced WM imaging techniques such as high-definition fiber tractography (HDFT). In this paper, we illustrate the application of HDFT, which in our preliminary experience has enabled accurate depiction of perilesional tracts in a 3-dimensional manner in multiple anatomical compartments including edematous zones around high-grade gliomas. This has facilitated accurate surgical planning. This is illustrated by using case examples of patients with glioblastoma multiforme. We also discuss future directions in the role of these techniques in surgery for gliomas.

The genomic landscape of schwannoma

Schwannomas are common peripheral nerve sheath tumors that can cause debilitating morbidities. We performed an integrative analysis to determine genomic aberrations common to sporadic schwannomas. Exome sequence analysis with validation by targeted DNA sequencing of 125 samples uncovered, in addition to expected NF2 disruption, recurrent mutations in ARID1A, ARID1B and DDR1. RNA sequencing identified a recurrent in-frame SH3PXD2A-HTRA1 fusion in 12/125 (10%) cases, and genomic analysis demonstrated the mechanism as resulting from a balanced 19-Mb chromosomal inversion on chromosome 10q. The fusion was associated with male gender predominance, occurring in one out of every six men with schwannoma. Methylation profiling identified distinct molecular subgroups of schwannomas that were associated with anatomical location. Expression of the SH3PXD2A-HTRA1 fusion resulted in elevated phosphorylated ERK, increased proliferation, increased invasion and in vivo tumorigenesis. Targeting of the MEK-ERK pathway was effective in fusion-positive Schwann cells, suggesting a possible therapeutic approach for this subset of tumors.

Cervical Spine Clearance in Obtunded Patients After Blunt Traumatic Injury: A Systematic Review

Cervical spine trauma is a major public health problem and a common reason for admission to trauma wards and intensive care units. The cervical spine is injured in 2.3% to 4.3% (14) of blunt traumas. Resultant neurologic impairment is encountered in 33% to 54% (57) of patients with cervical spine trauma. In fact, more than 50% of all acute spinal cord injuries affect the cervical spine (8, 9). Unfortunately, these injuries have poor functional outcomes. Mortality after traumatic cervical spinal cord injury may exceed 20% (1013), and survivors often face lifelong physical disability, along with the associated emotional, psychological, and social burdens (6, 8, 14, 15). The economic costs of spinal cord injury are enormous. In the United States, the total annual direct cost of spinal cord injuries approaches

Determining surgical candidacy in temporal lobe epilepsy.

8 billion (16). These factors make diligent and efficient cervical spine clearance protocols a critical priority. The exclusion of cervical spine injury in obtunded patients with trauma poses a significant challenge given the lack of a reliable clinical examination. Common practices at many trauma centers include routine acquisition of cervical spine magnetic resonance imaging (MRI), dynamic radiography (flexion and extension), or continued cervical immobilization until patients are awake and asymptomatic after a negative computed tomography (CT) scan (17, 18). These protocols may increase health care costs unduly, place critically ill patients at risk for deterioration during transportation, and prolong cervical collar immobilization and its associated illnesses. On the other hand, the consequences of missing an injury can be devastating and may include loss of functional ability, independence, and possibly life (1921). The primary aim of this study was to elucidate the role for further routine imaging or prolonged cervical immobilization in excluding significant cervical spine injury after negative CT results in obtunded patients who had blunt traumatic injury. Methods This systematic review was done according to a predefined protocol (Supplement) in accordance with MOOSE (Meta-analysis Of Observational Studies in Epidemiology) guidelines (22) and the PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) Statement (23). Supplement. Study Protocol Search Strategy We searched MEDLINE (PubMed and Ovid), EMBASE, CINAHL, Google Scholar, and the Cochrane Library from January 2000 through November 2014 for studies on the role of CT followed by a validating test in evaluating the cervical spine of obtunded trauma patients. We used, in various combinations, keywords and Medical Subject Headings terms pertinent to the patient population (altered, comatose, intensive care, intubated, mental status, obtunded, unconscious, unevaluable, unexaminable, unreliable, or unresponsive), medical condition (fracture, injury, instability, or trauma), anatomical site of interest (cervical-spine or cervical), and relevant radiological imaging methods (clearance, computed tomography, CT, dynamic, extension, flexion, fluoroscopy, imaging, magnetic resonance, MDCT, MR, MRI, plain film, radiograph, or X-ray). We also manually searched the references of relevant studies to identify additional studies for consideration. Selection Criteria Three investigators independently evaluated the studies for eligibility. Selection criteria included a study of any design (randomized, controlled trial; prospective cohort study; or retrospective cohort study). Studies were eligible if the diagnostic protocol of interest included a negative finding on a helical CT scan of the entire cervical spine followed by a confirmatory test. We included only the population of obtunded patients with blunt trauma (Glasgow Coma Scale [GCS] score 14, unreliable clinical examination, or intubation). Only English-language studies documenting the outcome measures of missed cervical spine injury or intervention after a negative CT result and additional findings of a validating test were included. We excluded studies with a sample size of fewer than 10 patients and studies in which partial cervical spine CT scans were used. For studies reporting data on overlapping cohorts from the same institution, we included only the study with the most inclusive cohort to prevent duplication. Studies evaluating only the pediatric population were excluded. Studies that examined awake and obtunded patients were included only if the outcomes of unreliable patients were analyzed separately. Abstracts from meeting proceedings were excluded if the data were not published in full-text articles in a peer-reviewed journal. Disagreements among the 3 reviewers about the decision to include or exclude a study were resolved by consensus and, if necessary, consultation with a fourth reviewer. Data Extraction and Quality Assessment Data from eligible studies were independently extracted by the 3 primary reviewers and verified for accuracy by the fourth reviewer. Discrepancies were resolved by discussion and consensus. We used data collection forms that included the following fields: title, author, year and country of publication, study design, sample size, patient demographic characteristics, Injury Severity Score, GCS score, definition of obtunded, mechanism of injury, CT specifications, further imaging or follow-up of patients with negative CT scans, image interpreter, missed acute cervical spine injuries, and changes in management. The 3 primary reviewers performed quality assessment independently. We used the QUADAS-2 (Quality Assessment of Diagnostic Accuracy Studies-2) tool (24) and examined patient selection, the index test and reference standard used, and flow and timing to determine whether the risk of bias and concerns about applicability to the review question were low, unclear, or high among eligible studies. Definition of Variables Our primary outcome of interest was clinically significant cervical spine injury missed by CT and detected by the confirmatory test. A clinically significant injury was defined as one resulting in mechanical instability or requiring intervention or change in management. We excluded soft tissue signal changes that did not affect spine stability. The definition of cervical spine instability varied among included studies and was assessed by using many classification systems. Most eligible studies defined instability in accordance with the work of White and Panjabi (25) on biomechanics of the spine. Previous studies defined unstable and purely ligamentous injuries as those involving all 3 columns (26). We adopted and documented cervical spine instability outcomes as reported by the authors of included studies, regardless of the classification used. Changes in management after negative CT results and positive findings on a validating test included prolonged external immobilization or operative stabilization. An obtunded patient was defined as someone who was not fully awake and had an altered level of consciousness (GCS 14). These patients lacked a reliable neurologic examination that could aid in the diagnosis of spinal injury. High-quality CT scans were defined as those protocolled with narrow slice width (1 to 3 mm) and reconstruction in multiple planes. A well-interpreted CT study was defined as an image read by a health professional with special training and expertise in reading such images (that is, a consultant radiologist) rather than an on-call physician or radiology resident. Data Synthesis and Analysis Studies were grouped on the basis of how further evaluation of obtunded trauma patients with negative results from cervical spine CT was handled. The first group included studies that routinely performed MRI after a CT scan that was interpreted as normal. The second group comprised studies in which patients were routinely evaluated with dynamic radiography after negative CT results. The third group included studies in which patients were followed with serial physical examination after a normal CT result, with further imaging obtained as guided by clinical indications (for example, neurologic deficit). For each group, we examined mechanical cervical spine instability, need for operative stabilization, and collar use after negative CT results and additional findings on the confirmatory test. We examined high-quality studies separately. These reports fulfilled 4 criteria: prospective study design, low risk of bias and low concerns about applicability in all domains on the QUADAS-2 tool, well-interpreted CT images, and use of high-quality CT specifications. Given the small number of events (if any), formal meta-analysis was not possible. Data from individual studies are displayed in forest plots with 95% CIs. Exact binominal 1-sided 95% CIs were calculated for each proportion obtained from eligible studies (27). We used R, version 3.1.2 (R Foundation for Statistical Computing), to generate all forest plots. Role of the Funding Source This study received no funding. Results Characteristics of Included Studies Our search yielded 2112 results, of which 1959 were excluded after title and abstract screening. Another 125 were excluded after full-text review (Appendix Figure). The remaining 28 studies (2855) were included, and they reported on a total of 3627 obtunded blunt trauma patients with negative results from cervical spine CT and a validating test. Twenty studies (28, 29, 32, 34, 35, 37, 4044, 46, 4855) were retrospective cohort studies, and 8 (30, 31, 33, 36, 38, 39, 45, 47) were prospective cohort studies. Descriptions of eligible studies are provided in Appendix Tables 1 and 2. Details of methodological assessment of included studies with the QUADAS-2 tool are presented in Appendix Table 3. Appendix Figure. Summary of evidence search and selection. CT = computed tomography. Appendix Table 1. Characteristics of Included Studies Appendix Table 2. Outcomes of Eligible Studies Appendix Table 3. Quality Assessment of Eligible Studies Wit

Stereotactic radiosurgery for intracranial meningiomas: current concepts and future perspectives.

Temporal lobe epilepsy (TLE) is the most common form of adult epilepsy that is amenable to surgical treatment. In the carefully selected patient, excellent seizure outcome can be achieved with minimal or no side effects from surgery. This may result in improved psychosocial functioning, achieving higher education, and maintaining or gaining employment. The objective of this paper is to discuss the surgical selection process of a patient with TLE. We define what constitutes a patient that has medically refractory TLE, describe the typical history and physical examination, and distinguish between mesial TLE and neocortical TLE. We then review the role of routine (ambulatory/sleep-deprived electroencephalography (EEG), video EEG, magnetic resonance imaging (MRI), neuropsychological testing, and Wada testing) and ancillary preoperative testing (positron emission tomography, single-photon emission computed tomography (SPECT), subtraction ictal SPECT correlated to MRI (SISCOM), magnetoencephalography, magnetic resonance spectroscopy, and functional MRI) in selecting surgical candidates. We describe the surgical options for resective epilepsy surgery in TLE and its commonly associated risks while highlighting some of the controversies. Lastly, we present teaching cases to illustrate the presurgical workup of patients with medically refractory TLE.

The role of 5‐aminolevulinic acid in enhancing surgery for high‐grade glioma, its current boundaries, and future perspectives: A systematic review

Meningiomas are among the most common adult brain tumors. Although the optimal management of meningiomas would provide complete elimination of the lesion, this cannot always be accomplished safely through resection. Therefore, other therapeutic modalities, such as stereotactic radiosurgery (as primary or adjunctive therapy), have emerged. In the current review, we have provided an overview of the historical outcomes of various radiosurgical modalities applied in the management of meningiomas. Furthermore, we provide a discussion on key factors (eg World Health Organization grade, lesion size, and lesion location) that affect tumor control and adverse event rates. We discuss recent changes in our understanding of meningiomas, based on molecular and genetic markers, and how these will change our perspective on the management of meningiomas. We conclude by outlining the areas in which knowledge gaps persist and provide suggestions as to how these can be addressed.

Deep brain stimulation for Parkinson’s disease: meta-analysis of results of randomized trials at varying lengths of follow-up

5‐Aminolevulinic acid (5‐ALA) has been approved as an intraoperative adjunct in glioma surgery in Europe, but not North America. A systematic review was conducted to assess the evidence regarding 5‐ALA as a surgical adjunct. The MEDLINE, EMBASE, and CENTRAL databases were searched, using terms relevant to “5‐ALA” and “high‐grade gliomas.” Included studies were based on adults aged ≥18 years who underwent surgical resection/biopsy. No language or date limitations were used. Forty‐three studies (1830 patients) were identified. Thirty‐six were coordinated by European countries, 2 were in the United States, and none were in Canada. One was randomized, 28 were prospective, and 14 were retrospective. Twenty‐six studies assessed the utility of 5‐ALA as a diagnostic tool, 24 assessed its influence on the extent of resection (EOR), 9 assessed survival, and 22 reported adverse events. 5‐ALA had high sensitivity and positive predictive value, whereas its specificity increased with additional adjuncts. The EOR increased with 5‐ALA, but only progression‐free survival was significantly influenced. Reporting of adverse events was not systematic. The use of 5‐ALA improved tumor visualization and thus enabled a greater EOR and perhaps increased survival. However, additional adjuncts may be necessary for maximizing the specificity of resection and patient safety. Additional parameters, such as patient quality of life and health economic analyses, would be informative. Thus, additional systematic collection of prospective evidence may be necessary for the global incorporation of this potentially valuable surgical adjunct into routine practice. Cancer 2016;122:2469–78.