RADIOTHERAPY--PREVENT FIBROSIS AFTER LUMBAR LAMINECTOMY

神经周围瘢痕形成，也被称为硬膜外纤维化，是腰椎间盘摘除手术后的常见情况。硬膜外纤维化可导致神经根受压或捆绑，并与腰椎间盘摘除术后复发的神经根性和/或下腰痛有关。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。打算切除这种纤维组织的再次手术通常会产生较差的手术效果和进一步的疤痕。此外，在动物模型的硬脑膜上植入了各种各样的材料，目的是预防神经周纤维化，但只取得了一定的成功。众所周知，低剂量辐射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。放射治疗作为一种抑制硬膜外纤维化的手段以前还没有被研究过。我们之前在大鼠和狗模型上进行的研究显示，在椎板切除术后，在手术前24小时给予低剂量外照射(700cGy)，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)手术前24小时给予手术前低剂量外照射将减少人类硬膜外纤维化的数量，以及(2)这种硬膜外纤维化的减少将导致患者预后的改善。在这项研究中，患者将参加一项随机、双盲、对照的临床研究，要么在手术前接受放射治疗(治疗组)，要么不接受手术前放射治疗(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的跟踪。由于美国每年有超过10,000名患者被认为是继发于硬膜外纤维化的背部手术失败综合征，这种新的治疗策略将对大量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.