Spinal Epiduroscopic Laser Therapy

Jae Do Kim and Gun Woo Lee

18.1 Introduction

Epiduroscopic procedure for the management of spine-related problems is one of the most commonly performed interventions; it is a minimally invasive approach and has theoretically several advantages, including: (1) adhesiolysis of pathologic lesions such as adhesion and scarred tissue; (2) chemical delusion by saline irrigation; and (3) additional anti-inflammatory effect using steroid. However, only a moderate proportion of patients show improvement in pain and functional level, and these relatively unsatisfactory outcomes suggest that additional methods should be sought to improve its efficacy, for which the additive use of laser can be an ideal option adapting with conventional procedure.

Clinical adaptation of laser has been shown to lead to favorable outcomes in spine territory as laser can reduce pressure by vaporizing a certain volume of disk material, which reduces the pressure between the nucleus pulposus and the peridiskal tissue, causing retraction of the herniation away from the dura and nerve root.1 Various types of laser for managing spinal disorders have been reported at the clinical or experimental level, including the neodymium:yttrium-aluminum-garnet (Nd:YAG) laser, frequency-doubled Nd:YAG laser, holmium:YAG (Ho:YAG) laser, and semiconductor laser. Of them, the Ho:YAG laser has a wavelength of 2.1 μm and reaches a depth of ≤ 0.5 mm in the tissue.^2,3,4,5,6,7 Tissue permeability is low, tissue vaporization is excellent, and the damage of surrounding tissue is minimal.⁴ In the author’s thought, the Ho:YAG laser may cause less damage to the surrounding tissues such as dura or nerve root in small enclosed spaces compared with other types of lasers, and thus we utilized it.

18.2 Procedures

18.2.1 Step 1: Position and Anesthesia

Each patient was instructed to lie on a radiologic testing table in the prone position; the skin in the region of the sacral hiatus was swabbed with disinfectant for sterilization ( Fig. 18.1 and Fig. 18.2), and local anesthesia with 1% lidocaine (Xylocaine, AstraZeneca) was administered ( Fig. 18.3).

Fig. 18.1 Patient position.

Fig. 18.2 Preparation.

During the procedure, no other sedatives were administered except the intravenous injection of meperidine hydrochloride (Demerol 25 mg, Sanofi-aventis U.S. LLC) to help ease the patients’ pain that occurred during procedure and to facilitate verbal communication between the surgical staff and patients throughout the procedure.

18.2.2 Step 2: Making a Portal for Procedure

An 18-gauge Tuohy epidural needle was used for puncturing the sacral hiatus and was advanced into the sacral canal under C-arm guidance ( Fig. 18.4, Fig. 18.5, and Fig. 18.6). Then, a guidewire was inserted into the opening via the needle that was removed ( Fig. 18.7 and Fig. 18.8). After applying 1-cm longitudinal skin incision at insertion site of guidewire, a dilator was then inserted through the opening to achieve the needed bony space ( Fig. 18.9), which was removed once the space was secured. After that, the epiduroscopic procedure should be initiated.

Fig. 18.3 Local anesthesia at incision site around sacral hiatus.

18.2.3 Step 3: Advancing to the Target Lesion

The introducer was inserted, followed by a flexible endoscope (Myelotec, model 75298871) into the epidural space through the introducer ( Fig. 18.10). The flexible endoscope was then maneuvered to reach the target lesion at either the ventral or the dorsal side of cauda equine ( Fig. 18.11). Epidural saline solution was used to irrigate and clear the area visualized, exert pressure to expand the epidural space, and improve clarity through the endoscopic video screen. This allowed visualization of adhesion status with bands, inflammatory tissues, fibrous connective tissues, and adipose tissue around the dura and nerve root, as well as anterior and posterior stenotic lesions such as thickened ligamentum flavum, hypertrophied facet joint, and protruded intervertebral disk ( Fig. 18.12).

In addition to securing epidural visibility endoscopically, a contrast agent (Omnipaque, Nycomed) was injected to perform epidurography to identify the adhesive lesion clearly under fluoroscopic image. We even stimulated the nerve roots in the lesion via the endoscope. This was to test if the stimulation induced concordant sensations or pain reproduction in the patient and to ensure a higher level of accuracy for our diagnosis, if it did. Next, we manipulated the flexible endoscope inside the epidural root lesion and performed adhesiolysis and foraminoplasty ( Fig. 18.13).