Epiduroscopic Ozone Therapy

Siddarth Thakur and Salahadin Abdi

24.1 Introduction

• Ozone is an allotropic form of oxygen, administered as an oxygen–ozone gas mixture at concentrations ranging from 1 to 40 μg per milliliter of oxygen and made in an ozone generator.1,2 Ozone is formed by an atom of oxygen and a molecule of oxygen, as represented in the mechanism: O þ O₂ ¼ O₃.

• It has been used for the treatment of back pain by minimally invasive techniques over the past two decades, particularly in Europe and South America.^1,3,4

• Ozone may be utilized with steroids, intradiskal radiofrequency, local anesthetics, collagenases, or antibiotics and administered intradiskally, intramuscularly (into the paraspinal muscles), or into the epidural space.^1,5

• Proposed mechanisms of action include mechanical and chemical adhesiolysis, reduction of inflammation, and shrinkage of intervertebral disk content.^2,3,6

• Ozone is a strong oxidizing agent that quickly reacts with collagens and proteoglycans in the nucleus pulposus of intervertebral disks causing resorption of water and reduction of disk volume, which, in turn, results in decreased mechanical irritation of nerves in the disk annulus and relief of nerve compression from herniated disks ( Fig. 24.1).^2,3

• Ozone improves perineural circulation and tissue oxygenation and also serves as an anti-inflammatory agent. Ozonized proteins inhibit proinflammatory signals, decrease free radical production, and block the expression of COX-2 enzymes and products such as prostaglandins.^2,3,5

• Epidurscopic ozone therapy consists of endoscopic adhesiolysis followed by instillation of ozone–oxygen gas mixture.

24.2 Indications

• Most commonly it used in patients suffering from failed back surgery syndrome (FBSS); the etiology of pain may be inflammatory changes in nerve roots, local ischemia,3 structural changes in vertebral column, lumbar degenerative disease, epidural fibrosis. and adhesions ( Fig. 24.2) which may compress nervous structures.⁴

• Also it is used for refractory low back pain secondary to degenerative disease with neurogenic claudication or radiculopathy, spondylolisthesis, spinal stenosis, or lumbar disk herniation, specifically in patients who fail conservative measures (physiotherapy and analgesics) and routine interventional procedures (epidural steroid and facet injections).^1,3,4,5,6

• It may serve as an alternative to additional open back surgery.

• Contraindications include allergy to ozone, glucose-6-phosphate dehydrogenase deficiency (favism), and hyperthyroidism, in addition to the contraindications for epiduroscopy (anticoagulant use, active infection, and compromised cardiac or pulmonary function).⁴

24.3 Technique

• Spinal endoscopy is carried out under local anesthesia with light sedation. The patient is awake to avoid unintentional pressure effects in the epidural space.4

• The patient is placed prone with pillows underneath hips for patient comfort and in order to straighten the lumbar.⁵

• Prophylactic antibiotics are administered.

Fig. 24.1 Mechanisms of ozone on inflammation reduction.

• The procedure is performed with aseptic technique and utilizes fluoroscopy.

• The sacral hiatus is identified and local anesthesia with 5 cc of 0.5% lidocaine is applied. An 18-gauge Touhy needle is then introduced with fluoroscopic confirmation of placement ( Fig. 24.3).⁶

Fig. 24.2 Epiduroscopic view demonstrating adhesions in the epidural space.

• A 0.9-mm guidewire is inserted through the needle and advanced till L5–S1 level ( Fig. 24.4).⁴

• The needle is removed ( Fig. 24.5), a no. 11 scalpel is used to make a 3-mm incision around the wire ( Fig. 24.6),⁵ and a 3.8 mm × 17.8 cm dilator is advanced over the guidewire ( Fig. 24.7).⁶

• The internal dilator is removed ( Fig. 24.8) and two-channel video-guided catheter (3.0 mm × 30 cm) is inserted with the fiberoptic microendoscope (0.8-mm spinal endoscope) ( Fig. 24.9).⁶

• With fluoroscopic guidance, the endoscope is directed to the level of suspected pathology ( Fig. 24.10).

• Saline irrigation is used for gentle distention of epidural space to allow for optimal visualization of nerve roots at multiple levels.

• After targeted nerve roots are identified, blunt dissection with hydrostatic distention allows for the creation of a pocket of space where the ozone can access the pathologic nerve roots ( Fig. 24.11).⁴