Bolster A A, Hilditch T E, Wheldon T E, Gaze M N, Barrett A
Department of Clinical Physics and Bio-Engineering, Western Infirmary, Glasgow, UK.
Br J Radiol. 1995 May;68(809):481-90. doi: 10.1259/0007-1285-68-809-481.
Dosimetric calculations have been made for organ doses in patients receiving 131I-MIBG therapy as treatment for neuroblastoma. As well as whole body and liver dose, consideration has been given to dosimetry of organs (lung, urinary bladder) whose tolerance may become treatment limiting when 131I-MIBG is given as part of combined modality therapy. Data from both adults and children receiving radiolabelled MIBG for diagnostic or therapeutic purposes have been compared in constructing dosimetry models for children. A recently published urodynamic model has been used in the estimation of radiation dose to the bladder. The results show that liver and lung may receive doses greater than the average total body dose (0.58 mGy MBq-1 and 0.35 mGy MBq-1, respectively, as compared with 0.25 mGy MBq-1 to the whole body). The organ dose estimates do not differ greatly from previous analyses except in the case of the bladder for which the new modelling studies have resulted in lower dose estimates (0.76 mGy MBq-1 administered, for dose to bladder surface from bladder contents) than in some published series. This may result from differing assumptions regarding parameters such as bladder content and urine flow rate, an enhanced fluid intake being assumed in the present bladder dose estimates. Average doses to the bladder wall from the contents were estimated to be 7.4-11.3% of the surface doses. The urodynamic modelling analysis shows that the bladder could receive a much greater dose (by an order of magnitude) in patients who were inadequately hydrated or had impaired renal function.
已对接受¹³¹I - MIBG治疗神经母细胞瘤的患者的器官剂量进行了剂量学计算。除了全身和肝脏剂量外，还考虑了在¹³¹I - MIBG作为联合治疗一部分使用时，其耐受性可能成为治疗限制因素的器官（肺、膀胱）的剂量学。在构建儿童剂量学模型时，比较了接受放射性标记MIBG用于诊断或治疗目的的成人和儿童的数据。最近发表的一个尿动力学模型已用于估算膀胱的辐射剂量。结果表明，肝脏和肺可能接受的剂量大于平均全身剂量（分别为0.58 mGy/MBq和0.35 mGy/MBq，而全身剂量为0.25 mGy/MBq）。器官剂量估计值与先前的分析相比差异不大，但膀胱情况除外，新的模型研究得出的剂量估计值（对于膀胱内容物给予膀胱表面的剂量为0.76 mGy/MBq）低于一些已发表系列中的值。这可能是由于对诸如膀胱内容物和尿流率等参数的假设不同，本研究在膀胱剂量估计中假设了增加的液体摄入量。膀胱内容物对膀胱壁的平均剂量估计为表面剂量的7.4 - 11.3%。尿动力学模型分析表明，在水分摄入不足或肾功能受损的患者中，膀胱可能接受大得多的剂量（相差一个数量级）。
