Utility of diffusion tensor imaging for guiding the treatment of lumbar disc herniation by percutaneous transforaminal endoscopic discectomy

The use of diffusion tensor imaging in spinal pathology: a comprehensive literature review

STUDY DESIGN

We reviewed the available literature systematically without meta-analysis following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

OBJECTIVE

To evaluate contemporary literature on use of spinal diffusion tensor imaging(sDTI) in spinal pathology.

BACKGROUND

sDTI reveals the location and functional state of critical long tracts and is a potentially useful adjunct in disease management.

METHODS

Studies were included if they presented or discussed data from investigative or therapeutic procedures involving sDTI on human subjects in the setting of surgically amenable spinal pathology. Studies were excluded if they were (1) restricted to computational models investigating parameters using data not obtained clinically, (2) about cranial DTI methods, (3) about spinal pathology data not related to surgical management, (4) discussions or overviews of methods/techniques with minimal inclusion of objective experimental or clinical data.

RESULTS

Degenerative pathologies of interest were restricted to either cervical myelopathy (22/29,75.9%) or lumbar spondylosis 7/29,24.1%). Mass-occupying lesions included intradural pathology and discussed preoperative (7/9,77.8%) and intraoperative imaging(2/9,22.2%) as an adjunct to surgery 22.2%. Traumatic pathology focused on spinal cord injury prognosis and severity grading.

CONCLUSIONS

sDTI seems useful in surgical decision making and outcome measurements and in establishing clinical prognoses over a wide range of surgical pathologies. Further research is warranted with longer follow-up and larger population sizes in a prospective and controlled protocol.

Percutaneous Transforaminal Endoscopic Surgery (PTES) for Treatment of Lumbar Degenerative Disease in Patients with Underlying Diseases: A Retrospective Cohort Study of 196 Cases

Objective

To evaluate the postoperative outcomes, safety and feasibility of percutaneous transforaminal endoscopic surgery (PTES) for the treatment of lumbar degenerative disease (LDD) in the patients with underlying diseases.

Methods

From June 2017 to April 2019, PTES was performed to treat 226 patients of single-level LDD. According to clinical background, the patients were divided into two groups. A total of 102 patients with underlying diseases were included in group A. The other 124 LDD patients without underlying diseases were included in group B. The occurrence of postoperative complications was recorded. Leg pain was assessed before, immediately, 1 month, 2 months, 3 months, 6 months, 1 year, and 2 years after PTES using VAS, and ODI before PTES and 2 years after PTES were recorded. The therapeutic quality (Excellent, Good, Moderate or Poor) was defined according to MacNab grade at 2-year follow-up.

Results

No aggravation of underlying diseases or serious complications was observed in all patients within 6 months after the operation. Altogether, 196 patients were followed up for more than 2 years, 89 patients in group A and 107 patients in group B. The VAS score of leg pain and ODI dropped significantly after surgery (P<0.001) in both groups. One case of group B received PTES again due to recurrence 52 months after surgery. According to MacNab, the excellent and good rate was 97.75% (87/89) in group A and 96.26% (103/107) in group B. In operative duration, frequency of intraoperative fluoroscopy, blood loss, incision length, hospital stay, VAS, ODI, and the excellent and good rate, there was no statistical difference between the two groups.

Conclusion

PTES is safe, effective and feasible for the treatment of LDD with underlying diseases, which is comparable to PTES for LDD without underlying diseases. The entrance point of PTES (Gu's Point) is located at the corner of the flat back turning to the lateral side. PTES is not only a minimally invasive surgical technique but also includes a postoperative care system for preventing LDD recurrence.

Value of diffusion tensor imaging and tractography in unilateral lumbar disc prolapse

Background

Conventional MR imaging is not enough for evaluation of symptomatic foraminal stenosis, because there is high incidence of false-positive results in asymptomatic elderly patients. Conventional MR cannot quantitatively assess the severity of the nerve lesion. DTI is a non-invasive way to effectively trace the nerve fiber bundle and quantitatively evaluate the nerve injury. DTI with fiber tracking may describe abnormalities beyond the resolution of conventional MR techniques. The aim of this work was to compare between the mean values of diffusion parameters such as fractional anisotropy and apparent diffusion coefficient of the compressed lumbar spinal nerve roots and of the contralateral normal nerve roots. Correlate these parameters with the severity of neurological symptoms. This is a prospective study that was conducted on 50 patients with symptomatic unilateral posterolateral lumbar disc prolapse at a university hospital. They were investigated with diffusion tensor imaging with tractography on a 1.5-T MR. The changes in the mean fractional anisotropy and apparent diffusion coefficient values of the compressed nerves and the relationship between these changes and the severity of the neurological side effects using Japanese Orthopedic Association score and visual analogue scale were investigated.

Results

The mean fractional anisotropy values were significantly lower (p ≤ 0.001), and mean apparent diffusion coefficient values were significantly higher (p ≤ 0.001) in compressed nerves than in contralateral intact nerves. There were strong correlations between the DTI parameters and the severity of the neurological symptoms as assessed using the Japanese Orthopedic Association score and the visual analogue scale.

Conclusion

In patients with lumbar disc prolapse, radicular diffusion parameters are affected in the compressed roots in comparison to the healthy roots and this affection is correlated with the degree of prolapse and with the severity of neurological symptoms. DTI with fiber tracking provide clinically relevant information and describe abnormalities beyond the resolution of conventional MR techniques.

Implementation of Percutaneous Transforaminal Endoscopic Discectomy in Competitive Elite Athletes With Lumbar Disc Herniation: Original Study and Review of the Literature

BACKGROUND

Lumbar disc herniation (LDH) represents a frequent clinical entity in athletes. Surgical treatment of LDH with endoscopic spine surgical techniques has been proposed as a feasible alternative in these patients.

PURPOSE

To study the particular outcomes of percutaneous transforaminal endoscopic discectomy (PTED) in competitive elite athletes with surgically treatable LDH.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

A total of 55 competitive elite athletes with diagnosed LDH based on clinical and radiologic criteria were enrolled in this prospectively designed study. All patients underwent successful PTED. Clinical evaluation was conducted with the well-established visual analog scale for lower limb and low back pain separately. The 36-Item Short Form Health Survey (SF-36) was implemented for health-related quality of life analysis. Patients were assessed preoperatively and at regular postoperative intervals: 6 weeks and 3, 6, and 12 months, as well as 2 years.

RESULTS

Operated levels were L3-L4 (5.5%), L4-L5 (69.1%), and L5-S1 (25.4%). No major perioperative complications were observed. All patients successfully reached the end of follow-up at 2 years. Both visual analog scale scores (lower limb and low back pain) showed clinically and statistically significant improvement at 6 weeks postoperatively, with subsequent minor improvement and stabilization. All recorded SF-36 parameters demonstrated major clinical amelioration at 6 weeks, with subsequent minor but constant statistically significant improvement until the end of follow-up. Comparative evaluation of the SF-36 revealed that the physical function, bodily pain, role-emotional, and mental health parameters showed quantitatively greater improvement in comparison with rest indices.

CONCLUSION

PTED constitutes a feasible and effective technique for surgical management of LDH in athletes, providing favorable outcomes in terms of postoperative pain and health-related quality of life. Proper performance of technique for specific cases of L5-S1 LDH may be more challenging, and these cases should be evaluated selectively for suitability for this procedure.

Clinical comparison of unilateral biportal endoscopic discectomy with percutaneous endoscopic lumbar discectomy for single l4/5-level lumbar disk herniation

OBJECTIVE

The purpose of this research was to investigate the outcomes between unilateral biportal endoscopic discectomy (UBE) and percutaneous endoscopic lumbar discectomy (PELD) for the single L4/5-level lumbar disk herniation (sLDH).

METHODS

From January 2018 to January 2021, a total of 40 patients with sLDH were retrospectively analyzed in this study. All the patients had received spinal surgeries in Affiliated Hospital of Nantong University and Affiliated Nantong Hospital 3 of Nantong University. Among them, 20 patients were treated with PELD (PELD group), and 20 patients were treated with UBE discectomy (UBE group). Postoperative length of hospital stay, estimated blood loss, operation time, and clinical complications of the patients were compared between the two groups. The visual analog scale (VAS) and Oswestry Disability Index (ODI) were measured before surgeries and 3 days, 1, and 6 months after surgeries.

RESULTS

Compared with the UBE group, the PELD group had obviously less intraoperative blood loss, shorter operative time, and shorter hospital stay. The differences in the rate of complications were not statistically significant between the two groups. The VAS score and the ODI score of the two groups had a great reduction after operation. In addition, both the groups had satisfactory clinical outcome; the VAS score and ODI of the PELD group decreased more obviously.

CONCLUSION

The UBE for sLDH yielded similar clinical outcomes to PELD as minimally invasive surgeries; however, PELD is superior to UBE in terms of intraoperative blood loss, operative time, postoperative hospitalization, and short-term postoperative pain relief. The advantages and disadvantages of the two surgeries should be circumspectly balanced when evaluating a patient for a minimally invasive surgery for sLDH, selecting the most appropriate surgical method for patients.

Prognostic Value of Michigan State University (MSU) Classification for Lumbar Disc Herniation: Is It Suitable for Surgical Selection?

BACKGROUND

Lumbar disc herniation (LDH) is the most common cause of radiculopathy; patients with severe pain refractory to conservative management or neurological deficits are candidates to surgical procedures. Michigan State University (MSU) classification is a radiological codification considering both the size of the LDH and its medial to lateral location on the axial plane. The purpose of this retrospective study is to identify which kind of LDH, according to the MSU scheme, is more likely to cause a motor deficit.

METHODS

We performed a retrospective analysis on data obtained from 114 patients treated with 117 lumbar microdiscectomies after failure of non-operative care. All patients underwent neurological and functional evaluation before and after surgery according to the following: Oswestry Disability Index, visual analog scale, and Japanese Orthopaedic Association back pain evaluation questionnaire. Magnetic resonance imaging proved that disc herniation was classified according to the MSU scheme and was correlated with motor disturbances expressed according to Medical Research Council grade.

RESULTS

Statistical analysis showed a significant correlation between the lateral location of disc herniation (preforaminal and extraforaminal LDH, respectively MSU B and MSU C) and the grade of muscle weakness, given that the LDH in these locations poorly responded to medical therapy and was at higher risk for motor deficit onset; no significant correlation with the size was observed.

CONCLUSIONS

Beyond standardization of radiologic description, MSU classification proved to be useful in definition of prognosis and possibly in selection of surgical candidates. However, these data should be confirmed by prospective studies on a larger sample of patients, also including those under way for conservative treatment.

Comparison of postoperative outcomes between patients with positive and negative straight leg raising tests who underwent full-endoscopic transforaminal lumbar discectomy

Full-endoscopic transforaminal lumbar discectomy (FETD) is increasingly used in patients with lumbar disc herniation (LDH). There is little knowledge on the related factors, including the straight leg raising test (SLR), that influence the operation. Consecutive patients with LDH who came to our hospital from August 2015 to September 2016 and underwent FETD surgery were included. Four kinds of scores, including the VAS (lumbar/leg), ODI and JOA values, were measured and reassessed after FETD to assess the surgical outcomes. There was a statistically significant difference between the scores before surgery and at each postoperative follow-up. In addition, the increase in the JOA score postoperatively was statistically significant compared with that before surgery. There were statistically significant differences among the three subpopulations [patients considered SLR positive (0°-30°), SLR positive (31°-60°) and SLR negative (61°-)] in the changes in the VAS (leg), ODI and JOA values. However, there were no statistically significant differences among the three subpopulations [patients considered SLR positive (0°-30°), SLR positive (31°-60°) and SLR negative (61°-)] in the changes in VAS score (lumbar). FETD showed great effectiveness in treating patients with lumbar disc herniation. Patients who were SLR negative may receive greater benefit from FETD.