Department of Radiation Oncology, McGill University Health Centre, Montreal, Quebec, Canada.
Int J Radiat Oncol Biol Phys. 2012 Mar 1;82(3):e501-5. doi: 10.1016/j.ijrobp.2011.07.024. Epub 2011 Dec 22.
To determine the best treatment technique for patients with retinoblastoma requiring radiotherapy to the whole eye.
Treatment plans for 3 patients with retinoblastoma were developed using 10 radiotherapy techniques including electron beams, photon beam wedge pair (WP), photon beam three-dimensional conformal radiotherapy (3D-CRT), fixed gantry intensity-modulated radiotherapy (IMRT), photon volumetric arc therapy (VMAT), fractionated stereotactic radiotherapy, and helical tomotherapy (HT). Dose-volume analyses were carried out for each technique.
All techniques provided similar target coverage; conformity was highest for VMAT, nine-field (9F) IMRT, and HT (conformity index [CI] = 1.3) and lowest for the WP and two electron techniques (CI = 1.8). The electron techniques had the highest planning target volume dose gradient (131% of maximum dose received [D(max)]), and the CRT techniques had the lowest (103% D(max)) gradient. The volume receiving at least 20 Gy (V(20Gy)) for the ipsilateral bony orbit was lowest for the VMAT and HT techniques (56%) and highest for the CRT techniques (90%). Generally, the electron beam techniques were superior in terms of brain sparing and delivered approximately one-third of the integral dose of the photon techniques.
Inverse planned image-guided radiotherapy delivered using HT or VMAT gives better conformity index, improved orbital bone and brain sparing, and a lower integral dose than other techniques.
确定需要全眼球放射治疗的视网膜母细胞瘤患者的最佳治疗技术。
使用包括电子束在内的 10 种放射治疗技术为 3 名视网膜母细胞瘤患者制定了治疗计划，包括光子束楔形对（WP）、光子束三维适形放疗（3D-CRT）、固定龙门强度调制放疗（IMRT）、光子容积弧形治疗（VMAT）、分次立体定向放疗和螺旋断层放疗（HT）。对每种技术进行了剂量-体积分析。
所有技术均能提供相似的靶区覆盖；VMAT、九野（9F）IMRT 和 HT 的适形性最高（适形指数[CI] = 1.3），WP 和两种电子技术的适形性最低（CI = 1.8）。电子技术的靶区剂量梯度最高（最大剂量[D(max)]的 131%），而 CRT 技术的剂量梯度最低（D(max)的 103%）。同侧骨眶至少接受 20 Gy（V(20Gy)）的体积，VMAT 和 HT 技术最低（56%），而 CRT 技术最高（90%）。一般来说，在保护大脑方面，电子束技术优于光子技术，并且提供的积分剂量约为光子技术的三分之一。
与其他技术相比，使用 HT 或 VMAT 进行逆向计划图像引导放疗可提供更好的适形指数，改善眼眶骨和大脑保护，并降低积分剂量。
