Spinal cord high-grade infiltrating gliomas in adults: clinico-pathological and molecular evaluation.

Primary high-grade infiltrating gliomas of the spinal cord are rare, with prior series including limited numbers of cases and reporting poor outcomes. Additionally, the molecular profile of high-grade infiltrating gliomas of the spinal cord has not been well characterized. We identified 13 adult patients whose surgery had been performed at our institution over a 26-year-period. Radiologically, nine cases harbored regions of post-contrast enhancement. Existing slides were reviewed, and when sufficient tissue was available, immunohistochemical stains (IDH1-R132H, H3-K27M, H3K27-me3, ATRX, p53 and BRAF-V600E), and a targeted 150-gene neuro-oncology next-generation sequencing panel were performed. The 13 patients included 11 men and 2 women with a median age of 38 years (range = 18-69). Histologically, all were consistent with an infiltrating astrocytoma corresponding to 2016 WHO grades III (n = 5) and IV (n = 8). By immunohistochemistry, six cases were positive for H3K27M, all showing concomitant loss of H3K27-me3. Next-generation sequencing was successfully performed in ten cases. Next-generation sequencing studies were successfully performed in four of the cases positive for H3K27M by immunohistochemistry, and all were confirmed as H3F3A K27M-mutant. Additional recurrent mutations identified included those of TERT promoter (n = 3), TP53 (n = 5), PPM1D (n = 3), NF1 (n = 3), ATRX (n = 2), and PIK3CA (n = 2). No HIST1H3B, HIST1H3C, IDH1, IDH2, or BRAF mutations were detected. Ten patients have died since first surgery, with a median survival of 13 months and 1 year of 46%. Median survival was 48.5 months for H3K27M-positive cases, compared to 1 month for those with TERT promoter mutation and 77 months for those harboring neither (p = 0.019). Median survival for cases with TP53 mutations was 11.5 months and for those with PPM1D mutations was 84 months. Our findings suggest that high-grade infiltrating gliomas of the spinal cord in adults represent a heterogeneous group of tumors, with variable outcomes possibly related to their molecular profiles.

The T2-FLAIR-mismatch sign as an imaging biomarker for IDH and 1p/19q status in diffuse low-grade gliomas: a systematic review with a Bayesian approach to evaluation of diagnostic test performance.

OBJECTIVE: With the revised WHO 2016 classification of brain tumors, there has been increasing interest in imaging biomarkers to predict molecular status and improve the yield of genetic testing for diffuse low-grade gliomas (LGGs). The T2-FLAIR-mismatch sign has been suggested to be a highly specific radiographic marker of isocitrate dehydrogenase (IDH) gene mutation and 1p/19q codeletion status in diffuse LGGs. The presence of T2-FLAIR mismatch indicates a T2-hyperintense lesion that is hypointense on FLAIR with the exception of a hyperintense rim. METHODS: In accordance with PRISMA guidelines, we performed a systematic review of the Ovid Medline, Embase, Scopus, and Cochrane databases for reports of studies evaluating the diagnostic performance of T2-FLAIR mismatch in predicting the IDH and 1p/19q codeletion status in diffuse LGGs. Results were combined into a 2 × 2 format, and the following diagnostic performance parameters were calculated: sensitivity, specificity, positive predictive value, negative predictive value, and positive (LR+) and negative (LR-) likelihood ratios. In addition, we utilized Bayes theorem to calculate posttest probabilities as a function of known pretest probabilities from previous genome-wide association studies and the calculated LRs. Calculations were performed for 1) IDH mutation with 1p/19q codeletion (IDHmut-Codel), 2) IDH mutation without 1p/19q codeletion (IDHmut-Noncodel), 3) IDH mutation overall, and 4) 1p/19q codeletion overall. The QUADAS-2 (revised Quality Assessment of Diagnostic Accuracy Studies) tool was utilized for critical appraisal of included studies. RESULTS: A total of 4 studies were included, with inclusion of 2 separate cohorts from a study reporting testing and validation (n = 746). From pooled analysis of all cohorts, the following values were obtained for each molecular profile-IDHmut-Codel: sensitivity 30%, specificity 73%, LR+ 1.1, LR- 1.0; IDHmut-Noncodel: sensitivity 33.7%, specificity 98.5%, LR+ 22.5, LR- 0.7; IDH: sensitivity 32%, specificity 100%, LR+ 32.1, LR- 0.7; 1p/19q codeletion: sensitivity 0%, specificity 54%, LR+ 0.01, LR- 1.9. Bayes theorem was used to calculate the following posttest probabilities after a positive and negative result, respectively-IDHmut-Codel: 32.2% and 29.4%; IDHmut-Noncodel: 95% and 40%; IDH: 99.2% and 73.5%; 1p/19q codeletion: 0.4% and 35.1%. CONCLUSIONS: The T2-FLAIR-mismatch sign is an insensitive but highly specific marker of IDH mutation but not 1p/19q codeletion in diffuse LGGs, although there may be significant exceptions. These findings support the utility of T2-FLAIR mismatch as an imaging-based biomarker for positive selection of patients with IDH-mutant gliomas.

Cervical Spondylotic Myelopathy: Metabolite Changes in the Primary Motor Cortex after Surgery.

Purpose To characterize longitudinal metabolite alterations in the motor cortex of patients with cervical spondylotic myelopathy (CSM) by using proton magnetic resonance (MR) spectroscopy and to evaluate white matter integrity with diffusion-tensor imaging in patients who are recovering neurologic function after decompression surgery. Materials and Methods Informed written consent was obtained for all procedures and the study was approved by Western University's Health Sciences Research Ethics Board. Twenty-eight patients with CSM and 10 healthy control subjects were prospectively recruited and underwent two separate 3-T MR imaging examinations 6 months apart. Patients with CSM underwent surgery after the first examination. N-acetylaspartate (NAA), an indicator of neuronal mitochondrial function, normalized to creatine (Cr) levels were measured from the motor cortex contralateral to the greater functional deficit side in the patient group and on both sides in the control group. Fractional anisotropy and mean diffusivity were measured by means of diffusion-tensor imaging in the white matter adjacent to the motor and sensory cortices of the hand and the entire cerebral white matter. Clinical data were analyzed by using Student t tests. Results In patients with CSM, NAA normalized to Cr (NAA/Cr) levels were significantly lower 6 months after surgery (1.48 ± 0.08; P < .03) compared with preoperative levels (1.73 ± 0.09), despite significant improvement in clinical questionnaire scores. Fractional anisotropy and mean diffusivity were the same (P > .05) between the patient and control groups in all measured regions at all time points. Conclusion NAA/Cr levels decreased in the motor cortex in patients with CSM 6 months after successful surgery. Intact white matter integrity with decreased NAA/Cr levels suggests that mitochondrial metabolic dysfunction persists after surgery. © RSNA, 2016 Online supplemental material is available for this article.

Time-to-enrollment in clinical trials investigating neurological recovery in chronic spinal cord injury: observations from a systematic review and ClinicalTrials.gov database.

Currently, large numbers of clinical trials are performed to investigate different forms of experimental therapy for patients suffering from chronic spinal cord injury (SCI). However, for the enrollment process, there are different views on how the time period between injury and interventions should be determined. Herein, we sought to evaluate the impact of time-to-enrollment in chronic SCI clinical trials. A data set comprising 957 clinical studies from clinicalTrials.gov was downloaded and analyzed focusing on the eligibility criteria for post-injury time-to-enrollment. We also aggregated individual patient data from nine clinical trials of regenerative interventions for chronic SCI selected by a systematic literature search from 1990 to 2018. Characteristics of the studies were assessed and compared by dividing into three groups based on time-to-enrollment (group 1 ≤ 12 months, group 2 = 12-23 months and group 3 ≥ 24 months). In ClinicalTrials.gov registry, 445 trials were identified for chronic SCI where 87% (385) were unrestricted in the maximum post-injury time for trial eligibility. From systematic literature search, nine studies and 156 patients (group 1 = 30, group 2 = 55 and group 3 = 71) were included. The range of time-to-enrollment was 0.5 to 321 months in those studies. We also observed various degrees of motor and sensory improvement in between three time-to-enrollment groups. Our results indicate that enrolling wide ranges of time-to-enrollment in a group may present imprecise outcomes. Clinical trial designs should consider appropriate post-injury time frames to evaluate therapeutic benefit.

Can spike fragments of SARS-CoV-2 induce genomic instability and DNA damage in the guppy, Poecilia reticulate? An unexpected effect of the COVID-19 pandemic.

The identification of SARS-CoV-2 particles in wastewater and freshwater ecosystems has raised concerns about its possible impacts on non-target aquatic organisms. In this particular, our knowledge of such impacts is still limited, and little attention has been given to this issue. Hence, in our study, we aimed to evaluate the possible induction of mutagenic (via micronucleus test) and genotoxic (via single cell gel electrophoresis assay, comet assay) effects in Poecilia reticulata adults exposed to fragments of the Spike protein of the new coronavirus at the level of 40 µg/L, denominated PSPD-2002. As a result, after 10 days of exposure, we have found that animals exposed to the peptides demonstrated an increase in the frequency of erythrocytic nuclear alteration (ENA) and all parameters assessed in the comet assay (length tail, %DNA in tail and Olive tail moment), suggesting that PSPD-2002 peptides were able to cause genomic instability and erythrocyte DNA damage. Besides, these effects were significantly correlated with the increase in lipid peroxidation processes [inferred by the high levels of malondialdehyde (MDA)] reported in the brain and liver of P. reticulata and with the reduction of the superoxide dismutase (SOD) and catalase (CAT) activity. Thus, our study constitutes a new insight and promising investigation into the toxicity associated with the dispersal of SARS-CoV-2 peptide fragments in freshwater environments.

Toxicity induced via ingestion of naturally-aged polystyrene microplastics by a small-sized terrestrial bird and its potential role as vectors for the dispersion of these pollutants.

In recent years, there has been a growing number of studies on the impact of microplastics (MPs) on biota. However, its effects on birds' health are poorly understood. Thus, we aimed to evaluate the possible effects of ingestion of naturally-aged MPs by Coturnix Coturnix japonica (11 and 22 MP particles/day/bird, once a day, for 9 days), from different toxicity biomarkers. At the end of the experiment, it was found that the ingested MPs in birds showed a significant reduction in body biomass. Also, an increase in malondialdehyde production in the liver, brain, intestine, and gizzard of the birds, as well as a suppressive effect on hepatic nitric oxide production and superoxide dismutase activity in the liver and intestine were observed. Cerebral catalase activity was reduced in birds exposed to MPs and the cholinesterasic effect (marked by increased acetylcholinesterase activity) was observed in the muscle and brain of these animals. Despite these differences, through the main component analysis, hierarchical clustering analysis, and integrated biomarker response assessment, we observed similar toxicological effects in birds exposed to different amounts of MPs. In addition, the size of MPs was reduced, and their shape was altered as they transited through the gastrointestinal system, which probably explains their accumulation in the liver of birds. An expressive number of MPs are released through the feces of the birds throughout the experiment. As far as we know, this is the first report that associates MPs ingestion by small-sized terrestrial birds with biochemical alterations viz., predictive of oxidative stress, redox imbalance, and cholinesterasic effect, in addition to shedding light on the potential role of these birds as vectors for dispersal of MPs in natural environments.

From carrion-eaters to plastic material plunderers: Toxicological impacts of plastic ingestion on black vultures, Coragyps atratus (Cathartiformes: Cathartidae).

Despite plastic ingestion has already been reported in several bird species, its physiological impacts have been little inspected, especially in representatives of the Cathartidae family. Thus, in this study, we aimed to identify, characterize, and evaluate the effects arising from the ingestion of plastic materials by Coragyps atratus adults, that captured in landfill areas. Herein, a total of 51 individuals were captured, the frequency of plastic intake being higher than 40%. The plastic materials consisted mainly of low-density polyethylene and film-type polystyrene, as well as presenting irregular shapes and diameters between 10 and 30 mm. Biochemically, we observed in animals that contained plastics in the stomach ("plastic" group) high production of reactive oxygen species (ROS), hydrogen peroxide (H2O2) and malondialdehyde (MDA) - especially in the intestine, muscle and brain - whose activity of catalase (CAT) and superoxide dismutase (SOD) was not sufficient to counteract the oxidative stress. Moreover, in the liver of these same animals, we observed high production of nitrite and nitrate, suggesting a hepatic nitrosative stress. Plus, we observed a cholinesterase effect in animals from the "plastic" group, marked by increased activity of butyrylcholinesterase (BChE) (in the brain) and muscle and cerebral acetylcholinesterase (AChE). On the other hand, the biochemical changes perceived were not significantly correlated with the identified plastic material concentrations (2.808 ± 0.598 items/g of stomach content and 0.276 ± 0.070 items/g of stomach - fresh weight), body condition of the animals, size, and shape of the identified plastic materials. Hence, our study sheds the light on the toxicity of plastics deposited in landfills and their ingestion by C. atratus, which reinforces the hypothesis that these materials are harming the health of these birds and, consequently, the dynamics of their populations.

Steel wools microfibers causes iron overload and induces biochemical changes in Gallus gallus domesticus chicks (Galliformes: Phasianidae).

Steel wool (SW) has a broad-spectrum of applicability, particularly as abrasives, cleaning household utensils and surfaces in general. However, when present in the natural environment, they can be ingested by animals, such as birds, and may represent a risk to the survival of individuals. Accordingly, in this study, we attempted the hypothesis that the ingestion of SW microfibers (SWMs) by Gallus gallus domesticus chicks (model system used) alters growth/development, induces redox imbalance and cholinesterasic effect, as well as promotes iron overload in different organs. For this, the animals received SWMs twice (within a 24-h interval) in an amount corresponding to 12% of their total stomach volume. At the end of the experiment, we observed less weight gain and less head growth, increased production of hydrogen peroxide (in the brain, liver, crop, and gizzard), nitrite (liver, crop, proventriculus and gizzard), malondialdehyde (brain, liver, muscle, proventriculus, and gizzard), along with increased superoxide dismutase activity in the liver, muscle and crop of animals exposed to SWMs. Such results were associated with iron overload observed in different organs, especially in liver, crop, and gizzard. Furthermore, we evidenced an anti-cholinesterasic effect in birds that ingested the SWMs, marked by a reduction in the acetylcholinesterase activity (in brain). Thus, our study sheds light on the (eco)toxicological potential of SWMs in avifauna, conceding us to associate their ingestion (despite ephemeral and occasional) with damage to the health of individuals, requiring a greater attention spotted to disposal of these materials in ecosystems.

Factors Associated with Higher Rates of Heterotopic Ossification after Spinal Cord Injury: A Systematic Review and Meta-Analysis.

Heterotopic Ossification (HO) refers to the formation of bone within soft tissue. Traumatic spinal cord injury (SCI) has been shown to be associated with development of HO. However, risk factors for HO following SCI are unknown. In light of this knowledge gap, we performed a systematic review and meta-analysis to summarize available evidence and elucidate risk factors associated with heterotopic ossification. An electronic literature search was conducted using five databases. Studies containing SCI patients, with a proportion diagnosed with HO, were included. Meta-analyses were performed to assess the association between following risk factors and development of HO: sex, type of injury, spasticity, pressure ulcer, injury level, urinary tract infection (UTI), deep vein thrombosis (DVT), number of smokers, and pneumonia. Nine studies with 2,115 patients were included. It was found that males (Odds Ratio [95% Confidence Interval]: 2.25 [1.61, 3.13]), smokers (2.88 [1.62, 5.11]), patients with complete injury (3.61 [2.29, 5.71]), pneumonia (2.86 [2.18, 3.75]), pressure ulcers (2.45 [1.89, 3.18]), UTI (3.84 [2.63, 5.62]) and spasticity (2.12 [1.67, 2.68]) had significantly higher odds of developing HO after spinal cord injury. In contrast, location of injury (Cervical vs. thoracic injury; (1.03 [0.72, 1.49]) and DVT (1.37 [0.91, 2.07]) were not associated with development of HO. Pooled results from existing literature on HO development show that several factors are significantly associated with development of HO. Given the complexity of SCI management, the results might have a positive impact on the clinical practice by leading to an effective screening aproach.

CELLTOP Clinical Trial: First Report From a Phase 1 Trial of Autologous Adipose Tissue-Derived Mesenchymal Stem Cells in the Treatment of Paralysis Due to Traumatic Spinal Cord Injury.

Spinal cord injury (SCI) is a devastating condition with limited pharmacological treatment options to restore function. Regenerative approaches have recently attracted interest as an adjuvant to current standard of care. Adipose tissue-derived (AD) mesenchymal stem cells (MSCs) represent a readily accessible cell source with high proliferative capacity. The CELLTOP study, an ongoing multidisciplinary phase 1 clinical trial conducted at Mayo Clinic (ClinicalTrials.gov Identifier: NCT03308565), is investigating the safety and efficacy of intrathecal autologous AD-MSCs in patients with blunt, traumatic SCI. In this initial report, we describe the outcome of the first treated patient, a 53-year-old survivor of a surfing accident who sustained a high cervical American Spinal Injury Association Impairment Scale grade A SCI with subsequent neurologic improvement that plateaued within 6 months following injury. Although he improved to an American Spinal Injury Association grade C impairement classification, the individual continued to be wheelchair bound and severely debilitated. After study enrollment, an adipose tissue biopsy was performed and MSCs were isolated, expanded, and cryopreserved. Per protocol, the patient received an intrathecal injection of 100 million autologous AD-MSCs infused after a standard lumbar puncture at the L3-4 level 11 months after the injury. The patient tolerated the procedure well and did not experience any severe adverse events. Clinical signs of efficacy were observed at 3, 6, 12, and 18 months following the injection in both motor and sensory scores based on International Standards for Neurological Classification of Spinal Cord Injury. Thus, in this treated individual with SCI, intrathecal administration of AD-MSCs was feasible and safe and suggested meaningful signs of improved, rather than stabilized, neurologic status warranting further clinical evaluation.

Does the Neurological Examination Correlate with Patient-Perceived Outcomes in Degenerative Cervical Myelopathy?

BACKGROUND: In patients with neurological disorders, a divergence can exist between patients' perceptions regarding the outcomes and the objective neurological findings. Degenerative cervical myelopathy (DCM), a prevalent condition characterized by progressive compression of the cervical spinal cord, can produce debilitating symptoms and profound neurological findings. The purpose of the present study was to determine whether the physician-derived neurological examination findings, as recorded by American Spine Injury Association (ASIA) summary score, correlated with the patient-derived outcome measures for DCM. METHODS: A total of 78 patients underwent surgical management of DCM with completion of preoperative and 6-month follow-up assessments. Surgical management consisted of either anterior or posterior cervical decompression. All patients underwent a neurological evaluation, including an ASIA assessment before surgery and 6 months after surgery, and completed the modified Japanese Orthopaedic Association (mJOA), neck disability index (NDI), and Short-Form 36-item (SF-36) scales pre- and postoperatively to measure both disease-specific and general perceived outcomes. RESULTS: The objective physician-derived neurological testing (ASIA) did not correlate with the patient-derived scales (mJOA, NDI, and SF-36) pre- or postoperatively. Patients reported significant improvements (P < 0.001) at 6 months postoperatively in extremity functioning (mJOA), neck pain (NDI), overall physical health (SF-36), and objective strength and sensory functioning (ASIA). All patient-perceived outcome measures correlated with each other pre- and postoperatively (P < 0.01). CONCLUSIONS: Objective scoring of postoperative neurological function did not correlate with patient-perceived outcomes before and after surgery for DCM. Traditional testing of motor and sensory function as part of the neurological assessment may not be sensitive enough to assess the scope of neurological changes experienced by patients with DCM.

Motor network recovery in patients with chronic spinal cord compression: a longitudinal study following decompression surgery.

OBJECTIVE The authors used functional MRI to assess cortical reorganization of the motor network after chronic spinal cord compression and to characterize the plasticity that occurs following surgical intervention. METHODS A 3-T MRI scanner was used to acquire functional images of the brain in 22 patients with reversible cervical spinal cord compression and 10 control subjects. Controls performed a finger-tapping task on 3 different occasions (baseline, 6-week follow-up, and 6-month follow-up), whereas patients performed the identical task before surgery and again 6 weeks and 6 months after spinal decompression surgery. RESULTS After surgical intervention, an increased percentage blood oxygen level-dependent signal and volume of activation was observed within the contralateral and ipsilateral motor network. The volume of activation of the contralateral primary motor cortex was associated with functional measures both at baseline (r = 0.55, p < 0.01) and 6 months after surgery (r = 0.55, p < 0.01). The percentage blood oxygen level-dependent signal of the ipsilateral supplementary motor area 6 months after surgery was associated with increased function 6 months after surgery (r = 0.48, p < 0.01). CONCLUSIONS Plasticity of the contralateral and ipsilateral motor network plays complementary roles in maintaining neurological function in patients with spinal cord compression and may be critical in the recovery phase following surgery.

Outcomes following minimally invasive lateral transpsoas interbody fusion for degenerative low grade lumbar spondylolisthesis: A systematic review.

A variety of surgical approaches have been described to treat low grade lumbar degenerative spondylolisthesis (DS). Minimally invasive spinal fusion techniques were first introduced to minimize morbidities associated with invasive surgical treatments. Minimally invasive lateral transpsoas interbody fusion, also known as lateral lumbar interbody fusion (LLIF), is a relatively new method of lumbar arthrodesis that avoids various approach related complications compared to its posterior and anterior counterparts. A systematic and critical review of recent literature was conducted in accordance with PRISMA guidelines. The sources of the data were PubMed, MEDLINE, Embase, Cochrane and Scopus. Key search terms were "transpsoas", "interbody fusion", "LLIF", "XLIF" and "spondylolisthesis". Papers included in the review were original research articles in peer-reviewed journals. The articles were thoroughly examined and compared on the basis of study design, outcomes, and results. Only studies which met the eligibility criteria were included. Eight studies were included in the qualitative and quantitative analysis (three retrospective, four prospective, one randomized controlled trial). A total of 308 patients (227 females) (pooled age 64.5 years) and a total of 353 operated levels were analyzed. Mean follow up time ranged from 6.2 to 24 months. There were no reported cases of durotomies or pseudarthrosis in any study. All neurologic complications were reported to be transient with no permanent deficits. Mean improvement in ODI scores ranged between 19.5 (38.6%) to 36 (54.5%). Mean improvement in slip ranged from 47 to 67.5%. Three studies also reported that patient satisfaction and willingness to undergo the procedure again approached 90%. Minimally invasive transpsoas interbody fusion possibly leads to favorable clinical and radiological outcomes while avoiding the possible complications of its more traditional open and minimally invasive counterparts. Further studies are needed to better establish its role in the management of low grade degenerative lumbar spondylolisthesis.

The impact of adding posterior instrumentation to transpsoas lateral fusion: a systematic review and meta-analysis.

OBJECTIVETranspsoas lateral interbody fusion is one of the lateral minimally invasive approaches for lumbar spine surgery. Most surgeons insert the interbody cage laterally and then insert pedicle or cortical screw and rod instrumentation posteriorly. However, standalone cages have also been used to avoid posterior instrumentation. To the best of the authors' knowledge, the literature on comparison of the two approaches is sparse.METHODSThe authors performed a systematic review and meta-analysis of the available literature on transpsoas lateral interbody fusion by an electronic search of the PubMed, EMBASE, and Scopus databases using PRISMA guidelines. They compared patients undergoing transpsoas standalone fusion (TP) with those undergoing transpsoas fusion with posterior instrumentation (TPP).RESULTSA total of 28 studies with 1462 patients were included. Three hundred and seventy-four patients underwent TPP, and 956 patients underwent TP. The mean patient age ranged from 45.7 to 68 years in the TP group, and 50 to 67.7 years in the TPP group. The incidence of reoperation was found to be higher for TP (0.08, 95% confidence interval [CI] 0.04-0.11) compared to TPP (0.03, 95% CI 0.01-0.06; p = 0.057). Similarly, the incidence of cage movement was found to be greater in TP (0.18, 95% CI 0.10-0.26) compared to TPP (0.03, 95% CI 0.00-0.05; p < 0.001). Oswestry Disability Index (ODI) and visual analog scale (VAS) scores and postoperative transient deficits were found to be comparable between the two groups.CONCLUSIONSThese results appear to suggest that addition of posterior instrumentation to transpsoas fusion is associated with decreased reoperations and cage movements. The results of previous systematic reviews and meta-analyses should be reevaluated in light of these results, which seem to suggest that higher reoperation and subsidence rates may be due to the use of the standalone technique.

Comparison of Outcomes for Anterior Cervical Discectomy and Fusion With and Without Anterior Plate Fixation: A Systematic Review and Meta-Analysis.

STUDY DESIGN: Systematic review and meta-analysis. OBJECTIVE: To compare postoperative surgical, radiographic, and patient-reported outcomes following anterior cervical discectomy and fusion (ACDF) with and without plate fixation. SUMMARY OF BACKGROUND DATA: ACDF has evolved significantly over the years, including the placement of an anterior plate construct. Although promoting bony osseo-integration at the fusion site, there are a number of plate-related complications that can arise. The non-plating approach is less invasive, however, greater rates of cage subsidence have been associated with this model. METHODS: We performed an electronic literature search for human studies that directly compared ACDF with and without anterior plate fixation. Outcomes of interest comprised of postoperative dysphagia, fusion success, and cage subsidence as well as patient reported outcomes, including the Neck Disability Index (NDI) scores and Visual Analog Scale (VAS) for both neck and arm pain. RESULTS: A total of 15 studies (12 observational and 3 randomized controlled trials) and 893 patients (57% males) were included. Overall, ACDF with plate fixation was associated with significantly higher vertebral fusion rates (odds ratio [OR] 1.98; 95% confidence interval [CI] 1.16-3.37), lower subsidence rates (odds ratio [OR] 0.31, 95% CI 0.18-0.52), and more favorable VAS-neck pain scores at last follow-up (mean difference [MD] 0.59, 95% CI -0.78 to -0.41). Conversely, ACDF procedures without plate fixation had marginally better long-term VAS-arm pain scores (mean difference [MD] 0.2, 95% CI 0.04-0.36). No difference was found with regards to dysphagia (OR 1.21, 95% CI, 0.57-2.56) and NDI (MD 0.06, 95% C.I -0.54 to 0.42). CONCLUSION: Available evidence, although limited, suggests superior surgical outcomes in ACDF procedures with anterior plate fixation (increased fusion, decreased subsidence) and slightly better VAS-neck pain scores at last follow-up. Future longitudinal, multicenter randomized controlled trials should be completed to validate any associations found in this study. LEVEL OF EVIDENCE: 3.

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.

Comparing outcomes of fusion versus repeat discectomy for recurrent lumbar disc herniation: A systematic review and meta-analysis.

OBJECTIVES: Current surgical treatment options for one-time recurrent lumbar disc herniation (RLDH) include repeat discectomy or discectomy supplemented with fusion. Significant contention exists within the surgical spine community with regard to the most effective treatment modality. The objective of this study is to compare reoperation rates and patient reported outcomes following fusion versus repeat discectomy for RLDH. PATIENTS AND METHODS: The electronic literature search was performed in Ovid Medline/Pubmed, EMBASE and Cochrane, Scopus and China National Knowledge Infrastructure for human studies directly comparing repeat discectomy with fusion for ipsilateral or contralateral RLDH. Random effects meta-analysis was conducted to pool the estimates of effect, using mean differences (MD) and odds ratios (OR) for continuous and categorical outcomes, respectively. RESULTS: A total of 1405 patients with RLDH (746 fusions and 659 repeat discectomies) from 15 studies (13 observational and 2 randomized controlled trials) were analyzed. Mean time to reherniation was 54.4 ±â€¯30.4 months, while average follow-up time was 40 ±â€¯11.7 months (range: 12-92.6). No difference was found between fusions and repeat discectomies with regards to related reoperations (OR: 0.68; 95% C.I: 0.14-3.2). Changes in PRO scores from baseline to last follow-up were also similar between the two groups, including VAS-back pain (MD, -0.3; 95% CI, -1.4 to 0.7), VAS-leg pain (MD, -0.3; 95% CI, -1.4 to 0.7), ODI (MD, 0.6; 95% CI, -0.2 to 1.4), JOA (MD: 1.0; 95% CI: 0.02 to 2.0) and MacNab satisfaction (OR: 1.5; 95% CI, 0.9 to 2.3). CONCLUSION: Available evidence shows that in treating one-time recurrent disc herniations, repeat discectomy and fusion are associated with comparable reoperation rates, incidence of dural tears, functional outcomes as well as satisfaction with surgical treatment at last follow-up. Future longitudinal, randomized controlled trials should be completed to validate any associations found in this study.

Metabolite and functional profile of patients with cervical spondylotic myelopathy.

OBJECTIVE The goal of this study was to compare the recovery of neuronal metabolism and functional reorganization in the primary motor cortex (M1) between mild and moderate cervical spondylotic myelopathy (CSM) following surgical intervention. METHODS Twenty-eight patients with CSM underwent 3-T MRI scans that included spectroscopy and functional MRI, before surgery and 6 months postsurgery. The classification of severity was based on the modified Japanese Orthopaedic Association questionnaire. Mild and moderate myelopathy were defined by modified Japanese Orthopaedic Association scores > 12 of 18 (n = 15) and 9-12 (n = 13), respectively. Ten healthy control subjects underwent 2 MRI scans 6 months apart. Metabolite levels were measured in the M1 contralateral to the greater deficit side in patients with CSM and on both sides in the controls. Motor function was assessed using a right finger-tapping paradigm and analyzed with BrainVoyager QX. RESULTS Patients with mild CSM had a lower preoperative N-acetylaspartate to creatine (NAA/Cr) ratio compared with moderate CSM, suggesting mitochondrial dysfunction. Postsurgery, NAA/Cr in moderate CSM decreased to the levels observed in mild CSM. Preoperatively, patients with mild CSM had a larger volume of activation (VOA) in the M1 than those with moderate CSM. Postoperatively, the VOAs were comparable between the mild and moderate CSM groups and had shifted toward the primary sensory cortex. CONCLUSIONS The NAA/Cr ratio and VOA size in the M1 can be used to discriminate between mild and moderate CSM. Postsurgery, the metabolite profile of the M1 did not recover in either group, despite significant clinical improvement. The authors proposed that metabolic impairment in the M1 may trigger the recruitment of adjacent healthy cortex to achieve functional recovery.

Quantitative evaluation of vision-related and health-related quality of life after endoscopic transsphenoidal surgery for pituitary adenoma.

OBJECTIVE Endoscopic resection of pituitary adenomas has been reported to improve vision function in up to 80%-90% of patients with visual impairment due to these adenomas. It is unclear how these reported rates translate into improvement in visual outcomes and general health as perceived by the patients. The authors evaluated self-assessed health-related quality of life (HR-QOL) and vision-related QOL (VR-QOL) in patients before and after endoscopic resection of pituitary adenomas. METHODS The authors prospectively collected data from 50 patients who underwent endoscopic resection of pituitary adenomas. This cohort included 32 patients (64%) with visual impairment preoperatively. Twenty-seven patients (54%) had pituitary dysfunction, including 17 (34%) with hormone-producing tumors. Patients completed the National Eye Institute Visual Functioning Questionnaire and the 36-Item Short Form Health Survey preoperatively and 6 weeks and 6 months after surgery. RESULTS Patients with preoperative visual impairment reported a significant impact of this condition on VR-QOL preoperatively, including general vision, near activities, and peripheral vision; they also noted vision-specific impacts on mental health, role difficulties, dependency, and driving. After endoscopic resection of adenomas, patients reported improvement across all these categories 6 weeks postoperatively, and this improvement was maintained by 6 months postoperatively. Patients with preoperative pituitary dysfunction, including hormone-producing tumors, perceived their general health and physical function as poorer, with some of these patients reporting improvement in perceived general health after the endoscopic surgery. All patients noted that their ability to work or perform activities of daily living was transiently reduced 6 weeks postoperatively, followed by significant improvement by 6 months after the surgery. CONCLUSIONS Both VR-QOL and patient's perceptions of their ability to do work and perform other daily activities as a result of their physical health significantly improved by 6 months after endoscopic resection of pituitary adenoma. The use of multidimensional QOL questionnaires provides a precise assessment of perceived outcomes after endoscopic surgery.

N-acetylaspartate in the motor and sensory cortices following functional recovery after surgery for cervical spondylotic myelopathy.

OBJECTIVE Cervical spondylotic myelopathy (CSM) is the most common cause of reversible spinal cord dysfunction in people over the age of 55 years. Following surgery for symptomatic CSM, patients demonstrate motor improvement early in the postoperative course, whereas sensory improvement can lag behind. The authors of the present study hypothesized that changes in the concentration of N-acetylaspartate (NAA) in the motor and sensory cortices in the brain would emulate the time course of neurological recovery following decompression surgery for CSM. Their aim was to compare and contrast how metabolite levels in the motor and sensory cortices change after surgery to reverse downstream spinal cord compression. METHODS Twenty-four patients with CSM and 8 control subjects were studied using proton MR spectroscopy (1H-MRS) images acquired on a 3.0-T Siemens MRI unit. The 1H-MRS data (TE 135 msec, TR 2000 msec) were acquired to measure absolute levels of NAA from the motor and sensory cortices in the cerebral hemisphere contralateral to the side of greater deficit at baseline in each subject. Data were also acquired at 6 weeks and 6 months following surgery. Control subjects were also evaluated at 6 weeks and 6 months following baseline data acquisition. Neurological function was measured in each subject at all time points using the Neck Disability Index (NDI), modified Japanese Orthopaedic Association (mJOA) questionnaire, and the American Spinal Injury Association (ASIA) neurological classification. RESULTS In the motor cortex of patients, NAA levels decreased significantly (p < 0.05) at 6 weeks and 6 months postsurgery compared with baseline levels. In the sensory cortex of patients, NAA levels decreased significantly (p < 0.05) only at 6 months after surgery compared with baseline and 6-week levels. No significant changes in NAA were found in control subjects. Clinical scores demonstrated significant (p < 0.05) motor recovery by 6 weeks, whereas sensory improvements (p < 0.05) appeared at only 6 months. CONCLUSIONS Findings suggest that metabolite changes in both the motor and sensory cortices mimic the time course of functional motor and sensory recovery in patients with CSM. The temporal course of neurological recovery may be influenced by metabolic changes in respective cortical regions.