Diffusion Tensor Imaging Studies of Cervical Spondylotic Myelopathy: A Systemic Review and Meta-Analysis

<div><p>A meta-analysis was conducted to assess alterations in measures of diffusion tensor imaging (DTI) in the patients of cervical spondylotic myelopathy (CSM), exploring the potential role of DTI as a diagnosis biomarker. A systematic search of all related studies written in English was conducted using PubMed, Web of Science, EMBASE, CINAHL, and Cochrane comparing CSM patients with healthy controls. Key details for each study regarding participants, imaging techniques, and results were extracted. DTI measurements, such as fractional anisotropy (FA), apparent diffusion coefficient (ADC), and mean diffusivity (MD) were pooled to calculate the effect size (ES) by fixed or random effects meta-analysis. 14 studies involving 479 CSM patients and 278 controls were identified. Meta-analysis of the most compressed levels (MCL) of CSM patients demonstrated that FA was significantly reduced (ES -1.52, 95% CI -1.87 to -1.16, P < 0.001) and ADC was significantly increased (ES 1.09, 95% CI 0.89 to 1.28, P < 0.001). In addition, a notable ES was found for lowered FA at C2-C3 for CSM vs. controls (ES -0.83, 95% CI -1.09 to -0.570, P < 0.001). Meta-regression analysis revealed that male ratio of CSM patients had a significant effect on reduction of FA at MCL (P = 0.03). The meta-analysis of DTI studies of CSM patients clearly demonstrated a significant FA reduction and ADC increase compared with healthy subjects. This result supports the use of DTI parameters in differentiating CSM patients from health subjects. Future researches are required to investigate the diagnosis performance of DTI in cervical spondylotic myelopathy.</p></div

Technical details of DTI studies on ALS in meta-analysis.

<p>DTI, diffusion tensor imaging; FA, fractional anisotropy; ADC, apparent diffusion coefficient; MD, mean diffusivity; ROI, region of interest; T, Tesla; FOV, field of voxel; NA, not available</p><p>Technical details of DTI studies on ALS in meta-analysis.</p

Quality assessment of studies according to Newcastle-Ottawa Scale.

<p>S1: Selection1-is the case definition adequate; S2: Selection2-representativeness of the cases; S3: Selection3-selection of controls; S4: Selection4-definition of controls. C1: Comparability1-comparability of controls for most important factor; C2: Comparability2-comparability of controls for other factors. E1: Exposure1-ascertainment of exposure; E2: Exposure2-same method of ascertainment for cases and controls; E3: Exposure3-non-response rate.</p><p>Quality assessment of studies according to Newcastle-Ottawa Scale.</p

Forest plot of Standardized mean differences (SMD) for FA at most compressed level between CSM patients and healthy controls.

<p>FA was significantly reduced in CSM patients. CI indicates confidence interval.</p

The relationship between effect size for FA and male ratio of CSM patients.

<p>The relationship between effect size for FA and male ratio of CSM patients.</p

Flow of identification of relevant studies.

<p>Flow of identification of relevant studies.</p

Forest plot of Standardized mean differences (SMD) for ADC at most compressed level between CSM patients and healthy controls.

<p>ADC was significantly increased in CSM patients. CI indicates confidence interval.</p

Forest plot of Standardized mean differences (SMD) for FA at C2-C3 level between CSM patients and healthy controls.

<p>FA was significantly reduced in CSM patients. CI indicates confidence interval.</p

Puncture Reduction in Percutaneous Transforaminal Endoscopic Discectomy with HE’s Lumbar LOcation (HELLO) System: A Cadaver Study

<div><p>Background</p><p>Percutaneous transforaminal endoscopic discectomy (PTED) usually requires numerous punctures under X-ray fluoroscopy. Repeated puncture will lead to more radiation exposure and reduce the beginners' confidence.</p><p>Objective</p><p>This cadaver study aimed to investigate the efficacy of HE’s Lumbar Location (HELLO) system in puncture reduction of PTED.</p><p>Study design</p><p>Cadaver study.</p><p>Setting</p><p>Comparative groups.</p><p>Methods</p><p>HELLO system consists of self-made surface locator and puncture locator. One senior surgeon conducted the puncture procedure of PTED on the left side of 20 cadavers at L4/L5 and L5/S1 level with the assistance of HELLO system (Group A). Additionally, the senior surgeon conducted the puncture procedure of PTED on the right side of the cadavers at L4/L5 and L5/S1 level with traditional methods (Group B). On the other hand, an inexperienced surgeon conducted the puncture procedure of PTED on the left side of the cadavers at L4/L5 and L5/S1 level with the assistance of our HELLO system (Group C).</p><p>Results</p><p>At L4/L5 level, there was significant difference in puncture times between Group A and Group B (P<0.001), but no significant difference was observed between Group A and Group C (P = 0.811). Similarly at L5/S1 level, there was significant difference in puncture times between Group A and Group B (P<0.001), but no significant difference was observed between Group A and Group C (P = 0.981). At L4/L5 level, there was significant difference in fluoroscopy time between Group A and Group B (P<0.001), but no significant difference was observed between Group A and Group C (P = 0.290). Similarly at L5/S1 level, there was significant difference in fluoroscopy time between Group A and Group B (P<0.001), but no significant difference was observed between Group A and Group C (P = 0.523). As for radiation exposure, HELLO system reduced 39%-45% radiation dosage when comparing Group A and Group B, but there was no significant difference in radiation exposure between Group A and Group C whatever at L4/L5 level or L5/S1 level (P>0.05). There was no difference in location time between Group A and Group B or Group A and Group C either at L4/L5 level or L5/S1 level (P>0.05).</p><p>Limitations</p><p>Small-sample preclinical study.</p><p>Conclusion</p><p>HELLO system was effective in reducing puncture times, fluoroscopy time and radiation exposure, as well as the difficulty of learning PTED. (2015-RES-127)</p></div

The schematic diagram of HELLO system.

<p>A: location theory of surface locator; B: location theory of puncture locator; C: real practice of surface locator; D: real practice of puncture locator.</p