Petrarca Robert, Jackson Timothy L
Department of Ophthalmology, King's College Hospital NHS Foundation Trust, London, UK.
Clin Ophthalmol. 2011 Jan 10;5:57-63. doi: 10.2147/OPTH.S16444.
Antivascular endothelial growth factor (anti-VEGF) therapies represent the standard of care for most patients presenting with neovascular (wet) age-related macular degeneration (neovascular AMD). Anti-VEGF drugs require repeated injections and impose a considerable burden of care, and not all patients respond. Radiation targets the proliferating cells that cause neovascular AMD, including fibroblastic, inflammatory, and endothelial cells. Two new neovascular AMD radiation treatments are being investigated: epimacular brachytherapy and stereotactic radiosurgery. Epimacular brachytherapy uses beta radiation, delivered to the lesion via a pars plana vitrectomy. Stereotactic radiosurgery uses low voltage X-rays in overlapping beams, directed onto the lesion. Feasibility data for epimacular brachytherapy show a greatly reduced need for anti-VEGF therapy, with a mean vision gain of 8.9 ETDRS letters at 12 months. Pivotal trials are underway (MERLOT, CABERNET). Preliminary stereotactic radiosurgery data suggest a mean vision gain of 8 to 10 ETDRS letters at 12 months. A large randomized sham controlled stereotactic radiosurgery feasibility study is underway (CLH002), with pivotal trials to follow. While it is too early to conclude on the safety and efficacy of epimacular brachytherapy and stereotactic radiosurgery, preliminary results are positive, and these suggest that radiation offers a more durable therapeutic effect than intraocular injections.
抗血管内皮生长因子（抗VEGF）疗法是大多数新血管性（湿性）年龄相关性黄斑变性（新血管性AMD）患者的标准治疗方法。抗VEGF药物需要反复注射，带来了相当大的护理负担，而且并非所有患者都有反应。放射治疗针对引起新血管性AMD的增殖细胞，包括成纤维细胞、炎症细胞和内皮细胞。目前正在研究两种新的新血管性AMD放射治疗方法：黄斑近距离放疗和立体定向放射外科手术。黄斑近距离放疗使用β射线，通过玻璃体切除术传递到病变部位。立体定向放射外科手术使用重叠光束中的低电压X射线，直接照射到病变部位。黄斑近距离放疗的可行性数据显示，抗VEGF治疗的需求大幅减少，12个月时平均视力提高8.9个ETDRS字母。关键试验正在进行中（MERLOT、CABERNET）。立体定向放射外科手术的初步数据表明，12个月时平均视力提高8至10个ETDRS字母。一项大型随机假对照立体定向放射外科手术可行性研究正在进行中（CLH002），随后将进行关键试验。虽然现在就得出黄斑近距离放疗和立体定向放射外科手术的安全性和有效性结论还为时过早，但初步结果是积极的，这表明放射治疗比眼内注射具有更持久的治疗效果。
