Kinsella T J, Sindelar W F, DeLuca A M, Pezeshkpour G, Smith R, Maher M, Terrill R, Miller R, Mixon A, Harwell J F
Int J Radiat Oncol Biol Phys. 1985 Sep;11(9):1579-85. doi: 10.1016/0360-3016(85)90209-3.
In our clinical experience combining wide excision and intraoperative radiotherapy (IORT), five patients have developed clinical signs of lumbosacral or sciatic neuropathy within 9 months of receiving IORT to a dose of 20-25 Gy. Three patients showed recovery of nerve function over several months while two patients have shown no recovery and have near complete loss of extremity function. In an attempt to investigate this clinical observation further, the lumbosacral plexus and sciatic nerve of American foxhounds were surgically exposed and received a single dose of IORT ranging from 20-75 Gy. An approximate linear relationship between radiation dose and time to onset of hind limb paresis is found with 19 of 21 irradiated dogs showing clinical signs of nerve injury within an interval of 1-19 months. No recovery of nerve function is seen in these dogs. Histological study of the irradiated nerves demonstrates a loss of nerve fibers, particularly those of the large myelinated type without evidence of vascular occlusion or thrombosis. These studies suggest that peripheral nerve may be a dose-limiting normal tissue in clinical studies of IORT.
根据我们将广泛切除与术中放疗（IORT）相结合的临床经验，有5例患者在接受20 - 25 Gy剂量的IORT后9个月内出现了腰骶部或坐骨神经病变的临床症状。3例患者在数月内神经功能有所恢复，而2例患者未恢复，肢体功能几乎完全丧失。为了进一步研究这一临床观察结果，对美国猎狐犬的腰骶丛和坐骨神经进行手术暴露，并给予20 - 75 Gy的单次IORT剂量。发现辐射剂量与后肢轻瘫发作时间之间存在近似线性关系，21只接受照射的犬中有19只在1 - 19个月内出现神经损伤的临床症状。这些犬未见神经功能恢复。对受照射神经的组织学研究显示神经纤维减少，尤其是大的有髓鞘型神经纤维，且无血管闭塞或血栓形成的证据。这些研究表明，在IORT的临床研究中，周围神经可能是一种剂量限制正常组织。
