Objective To explore the feasibility and clinical efficacy of modified transforaminal lumbar interbody fusion for the treatment of lumbar spinal stenosis with lumbar instability in the elderly.Methods Retrospective study was done on 45 elderly patients diagnosed as lumbar spinal stenosis with lumbar instability treated by modified transforaminal lumbar interbody fusion from June 2011 to December 2012.There were 25 males and 20 females aged from 65 to 78 years [mean (70.64.0) years].The operation time,blood loss,and complications were recorded and analyzed.The visual analog scale (VAS) score,and Japanese Orthopaedic Association (JOA) score were used to assess clinical outcomes before and 3 months after treatment and at the last follow-up.According to the criteria of Brantigan-Steffe,intervertebral fusion was evaluated.Results The operation of 45 patients was successful,and there were no severe complication.The average operative time was (126 23) min,(range,100～ 185 min),and the average amount of blood loss was (272±89) ml (range,180-550 ml).There was no injury of nerve root,dural tear,or deep infection.All patients were followed up for 12 months to 30 months with an average of (20.6±5.8) months.The VAS score of low back pain was decreased from (4.8 ± 1.7) before operation to (1.6 ± 0.5) at 3 months after operation and (1.3±0.3) at last follow-up.The VAS score of leg pain was decreased from (6.7±1.6) before operation to (1.2±0.5) at 3 months after operation and (0.6±0.3) at last follow-up.The JOA score was increased from (13.2±4.9) before operation to (23.8±4.0) at 3 months after operation and (24.1 4.2) at last follow-up.There were significant differences in the VAS score and JOA score between pre-and post-operation (F=68.35,98.58,89.73,all P＜0.05),but no significant difference between 3 months after operation and final follow-up (all P ＞ 0.05).We observed no pedicle screw loosening,breaking,orany pullingout of intervertebral fusion cage.All patients showed evidence of fusion in each operated segment according to the criteria of BrantiganSteffe.Conclusions Modified transforaminal lumbar interbody fusion has the advantages including less invasion,sufficient decompression,and less interference to neural structures,and it may provide an ideal surgical method for lumbar spinal stenosis with lumbar instability in the elderly.

BACKGROUND:In clinical application,the therapeutic effect of transcranial magnetic stimulation depends on the ability to accurately target the areas of the brain that need to be stimulated.In recent years,with the development of neuronavigation systems,mobile augmented reality technology,and the new methods of processing magnetic resonance imaging(MRI)data,the accuracy of stimulus target localization and the optimization of target selection are expected to improve further. OBJECTIVE:To review the principle of MRI-based image navigation and its application in transcranial magnetic stimulation and summarize the roles of different modal MRI data analyses in guiding the selection of target areas for transcranial magnetic stimulation. METHODS:An online computer search for relevant literature was performed in PubMed,CNKI database and WanFang database,with the keywords"transcranial magnetic stimulation,coil positioning,neuronavigation,augmented reality,magnetic resonance,theory."Finally,63 documents were included for review. RESULTS AND CONCLUSION:Among the traditional methods of positioning transcranial magnetic stimulation coils,the"5 cm rule"and the international electroencephalogram 10-20 positioning method are the most commonly used.These methods have the advantages of simplicity and economy,but they rely too much on the operator's experience and there were technical differences between operators.The neuronavigation system,which is based on stereotactic technology,is the guiding method for positioning transcranial magnetic stimulation coils with the highest visual degree and accuracy.It achieves visual positioning through MRI data acquisition,3D brain reconstruction,head model registration and stereogeometric positioning.It has high application value in clinical treatment and scientific research,but it cannot be promoted in medical institutions due to its high cost.For various medical institutions,mobile augmented reality is a cost-effective and efficient alternative to the neuronavigation system,which achieves visual positioning of brain tissue under the scalp through MRI data acquisition,2D/3D image construction,virtual image and real brain image superposition.It has the advantages of directly visualization and low cost,and is expected to be popularized and applied in primary medical units.Although the superiority of clinical efficacy of visual coil positioning over the electroencephalogram 10-20 localization strategy has not yet been fully demonstrated,with the progress of brain MRI data analysis,visual positioning is expected to further optimize the target selection strategy of transcranial magnetic stimulation therapy and to improve the response rate and individuation degree of transcranial magnetic stimulation treatment.This is a promising and challenging research direction in the future.