501 - Can the Biportal Endoscopic Surgery Achieve Enough Canal Decompression...

General Session: Endoscopic Surgery

Presented by: C.K. Park


C.K. Park(1), D.H. Heo(1)

(1) The Leon Wiltse Memorial Hospital, Suwon, Korea, Republic of


Background: Unilateral laminotomy with bilateral decompression (ULBD) was widely accepted surgical treatment for lumbar degenerative canal stenosis. Recently, minimally invasive full endoscopic ULBD have been attempted instead of microsurgery. Although favorable postoperative outcomes of percutaneous endoscopic lumbar decompression has bee presented, there were no reports of postoperative radiologic outcomes; whether endoscopic decompressive surgeries can achieve enough canal decompression or not. The purpose of this study is to investigate the radiologic outcome of percutaneous unilateral biportal endoscopic (UBE) decompression comparing to conventional microscopic decompressive surgery. Also, we additionally studied clinical results of percutaneous UBE decompression.

Methods: The study design was a case control study. Since March 2016, we had prospectively performed microscopic ULBD in 56 patients and percutaneous UBE decompression in 67 patients. Patients were classified into two groups by operation methods (microscopic group and UBE group). Only patients who were followed more than 6 months after operations were enrolled. The area of dura was measured by an automatic area calculation program of PACS systems. The preoperative and postoperative dura areas were measured at six axial cuts of T2 weighted MR images. The degree of postoperative dura expansion was calculated by difference between postoperative and preoperative dura area. We analyzed clinical parameters such as visual analogue scale (VAS) of back and leg pain, Oswestry disability index (ODI), and perioperative complications. Radiologic and clinical outcomes were analyzed by two investigators without any information of surgery. Radiologic and clinical outcomes were compared between two groups (microscope group and UBE group).

Results: Finally, 88 patients were enrolled in this study. There were 42 patients of microscope group and 46 patients of UBE group. The mean follow-up period was 8.5± 4.3 months. Postoperatively, dura was significantly expanded in each group (P< 0.05). And there was no difference of dura expansion between two groups (P>0.05). VAS and ODI were significantly improved after surgery in each two groups (P< 0.05). Immediate postoperative pain score was significantly higher in microscope group rather than in UBE group (P< 0.05). There was no significant difference in the incidence of perioperative complications such as epidural hematoma and durotomy between two groups (P>0.05).

Conclusions: The results of this study demonstrate that the full-endoscopic ULBD using biportal endoscopic approach may be a safe and effective treatment for the lumbar stenosis and an alternative to the conventional microsurgical technique. We were able to perform enough canal decompression using UBE technique similar to microscopic surgery. At the same time, it offers the advantages of a minimally invasive intervention. However, we need long-term follow-up and a more detailed study for more accurate results of this technique.