Percutaneous Laser Disc

The declining popularity of chemonucleolysis and APLD led to the emergence of alternative techniques that employed thermal energy techniques such as laser and radiofrequency nucleotomy. Arguably, the advantage of thermal techniques is that they provide a combination of mechanical decompres- sion and modification of intradiscal biochemical milieu, which can lead to the reduction of neuropathic (radiculopathic) and nociceptive pain, respectively. Procedure The first clinical application of PLDD occurred in 1986. Various types of lasers have since been described in the literature, including those with wavelengths close to the infrared region (Nd:YAG, Ho:YAG, and diode lasers) and those with visible green radiation (potassium-titanyl-phosphate (KTP) laser).The working principle of PLDD is similar to other decompression techniques; access to intervertebral disc is achieved similar to other percutaneous techniques except with a smaller diameter needle (18- gauge needle), followed by the introduction of 400-μm optical fiber for transmission of laser energy. Different protocols have been reported in the literature in terms of the type of laser, duration of the treatment, and impulsion energy used to achieve decompression. Gangi and coworkers reported that the application of a 1,064-nm Nd:YAG laser in short pulses of 0.5–1 s with pauses of 4–10 s was effective, while Choy and coworkers reported the use of a 1,064-nm Nd:YAG laser in short pulses of 1 s and pauses of 1 s led to a favorable outcome. As with APLD, the patient is then allowed to recover and dis- charged home on the day of the procedure. Evidence of Efficacy To date, most observational studies on PLDD have reported favorable outcomes. Tassi, Choy, and coworkers reported a success rate of 70–89 % based on the results from multiple centers and approximately 20,000 procedures. The complication rate (complications were mainly discitis) ranged from 0.3 to 1.0 %, and there was a recurrence rate of 4–5 % over a 23-year follow-up period. In a systematic review that encompassed 14 observational studies, Singh and coworkers reported that there was only modest evidence that the use of PLDD led to short- and long-term pain relief and that the procedure had a success rate of 56–87 %. However, the lack of well-designed randomized clinical trials and the methodological weakness of the above studies question the validity of these conclusions.