RADIOTHERAPY--PREVENT FIBROSIS AFTER LUMBAR LAMINECTOMY

神经周围瘢痕形成，也称为硬膜外纤维化，是腰椎间盘切除术后常见的现象。 硬膜外纤维化可引起神经根的压迫或束缚，并与腰椎间盘切除术后复发性神经根痛和/或腰痛有关。 纤维化可能是多达四分之一的背部手术失败综合征病例的根本原因。 再次手术切除这种纤维组织往往会产生不良的手术效果和进一步的疤痕。 此外，已经在动物模型中将各种各样的材料植入到硬脑膜上，目的是预防神经周围纤维化，但仅取得了一定的成功。长期以来，低剂量辐射被认为会抑制成纤维细胞和成骨细胞的活性。 在人体试验中，围手术期放射治疗已被证明是预防瘢痕疙瘩和异位骨形成的有效方法。 以前没有研究放射作为抑制硬膜外纤维化的手段。我们之前在大鼠和犬模型中进行的研究表明，在手术前24小时给予低剂量外照射（700 cGy）进行椎板切除术后，硬膜外纤维化显著减少。 基于这些初步数据，我们将检验以下假设：（1）术前24小时给予术前低剂量外照射将减少人类硬膜外纤维化的数量，（2）硬膜外纤维化的减少将改善患者的结局。 对于本研究，患者将入组随机双盲对照临床研究，术前接受放疗（治疗组）或术前不接受放疗（对照组）。患者将在1、3、6和12个月时接受功能自我报告工具、损伤测量和磁共振成像随访。 由于美国每年有超过10，000名患者患有被认为继发于硬膜外纤维化的背部手术失败综合征，因此这种新型治疗策略对大量患有这种疾病过程的患者有效。

Perineural scar formation, also known as peridural fibrosis, is a common occurrence after lumbar discectomy surgery. Peridural fibrosis can cause compression or tethering of the nerve root and has been implicated in recurrent radicular and/or low back pain after a lumbar discectomy. Fibrosis may be the underlying cause in as many as a quarter of all failed back surgery syndrome cases. Reoperation with the intention of excising this fibrous tissue often produces a poor surgical result and further scarring. Furthermore, a large variety of materials have been implanted onto the dura in animal models with the goal of preventing perineural fibrosis with only modest success. Low dose radiation has long been known to inhibit fibroblast and osteoblast activity. Perioperative radiation therapy has been demonstrated to be a useful method to prevent both keloid and heterotopic bone formation in human trials. Radiation has not previously been studied as a means to inhibit peridural fibrosis. Our previous studies investigating in both rat and dog models showed a significant reduction in peridural fibrosis after laminectomy using low dose external beam radiation (700 cGy) given 24 hours prior to surgery. Based on these preliminary data, we will test the hypotheses that (1) preoperative low dose external beam radiation given 24 hours prior to surgery will decrease the amount of peridural fibrosis in humans, and (2) this reduction in peridural fibrosis will lead to an improvement in patient outcome. For this study, patients will be enrolled in a randomized double-blinded controlled clinical investigation either to preoperative radiation (treatment group) or no preoperative radiation (control group) prior to surgery. Patients will be followed at 1, 3, 6, and 12 months with self- report instruments of function, measures of impairment, and magnetic resonance imaging. As more than 10,000 patients per year in the United States have failed back surgery syndrome thought secondary to peridural fibrosis, this novel treatment strategy would be efficacious to a large number of patients with this disease process.