The purpose of this study is to evaluate the feasibility and efficacy of US-MR image fusion-guided percutaneous transforaminal endoscopic discectomy for the treatment of lumbar disc herniation

Lumbar disc herniation (LDH) is a common pathological process leading to spinal surgery. Open discectomy used to be a widespread procedure for surgical treatment for symptomatic LDH. Currently, with rapid progress of endoscopic techniques, several minimal invasive endoscopic surgeries have been developed to perform discectomy. Percutaneous transforaminal endoscopic discectomy (PTED) a widely used minimal invasive surgical procedures, the effectiveness of which has been proved to be comparable to conventional open discectomy. However, the use of fluoroscopy may be usually required to indirectly visualize pertinent anatomy to achieve an optimal result on radiographs. As we known, increased radiation exposure may be associated with potential stochastic and deterministic adverse events. Therefore, it is important to reduce the radiation dose of practitioners to minimize risk of potential radiation-induced complications.

Ultrasound-MR fusion technique combines the advantages of ultrasound and MR, and overcome the shortcomings of each single imaging method. It provides MR cross-sectional multiplanar images that correspond to the acquired real-time US images, and all images can be displayed simultaneously and in real time according to the angle of the US transducer. US-MR fusion image has been widely used in prostate and liver intervention. However, to our limited knowledge, there is only one research about the application of US-MR fusion image in lumbar spinal surgery.

In this study, a comparative cohort study will be performed to evaluate feasibility and efficacy of US-MR image fusion-guided percutaneous transforaminal endoscopic discectomy for the treatment of lumbar disc herniation(LDH). We will conduct the study at the 3rd affiliated hospitals of Sun Yat-Sen University.

Two groups of patients will be investigated: patients diagnosed with lumbar disc herniation undergoing US-MR image fusion-guided PTED (US-MR PTED), and fluoroscopy-guided PTED (FL PTED).

The primary outcomes of the study will be radiation exposure and puncture time. Secondary outcomes include fusion efficacy, puncture accuracy, puncture satisfaction of surgeon, comfort of patient and clinical effectiveness.

On the basis of the results of this trial we will, for the first time, have scientific evidence as to the feasibility and efficacy of US-MR image fusion-guided percutaneous transforaminal endoscopic discectomy for the treatment of lumbar disc herniation.

Inclusion Criteria:

1. persistent radicular pain.
2. an imaging study (MRI or CT) showing LDH at a level and side corresponding to the patient
3. single responsible segment of lumbar disc herniation
4. L4-5 segment

Exclusion Criteria:

1. Cauda equina syndrome or progressive neurologic deficit requiring urgent surgical intervention
2. Combination with other spinal disorder requiring advanced surgery (such as lumbar stenosis, spondylolisthesis, deformity, fracture, infection, tumor and so on)
3. Equal to or more than two responsible level
4. Previous spinal surgery
5. unable to collaborate during surgery
6. far-lateral disc herniation