放射性视神经病变临床分析

Clinical analysis of radiation optic neuropathy

目的探讨放射性视神经病变（RON）的临床特点、影响因素、诊治方法及其转归。方法回顾性系列病例研究。对1999年6月至2010年10月中山大学中山眼科中心收治的35例（60只眼）RON住院患者的临床资料进行回顾性分析。结果共收集35例（61只眼）RON患者的临床资料。所有患者均以进行性、无痛性单眼或双眼视力下降为主要表现。18例（51．4％）在完成放射治疗后3年内出现眼部症状。43只眼（70．5％）的患眼入院时中心最佳矫正视力〈0．05或视野0。。可窥见眼底的52只眼中，41只眼（78．8％）视乳头边界清晰，11只眼（21．2％）视乳头水肿和（或）出血、渗出。视乳头边界清晰的41只眼中，视乳头正常6只眼（14．6％），视乳头色较淡30只眼（73．2％），视乳头苍白5只眼（12．2％）。14只眼有视野检查记录，主要表现为神经纤维束损害性视野缺损，其中7只眼（50％）表现为上方和（或）下方弓形暗点，3只眼（21．4％）出现中心和（或）旁中心暗点，2只眼伴生理盲点扩大，1只眼伴旁中心暗点，1只眼见鼻上象限缺损。23只眼有视网膜荧光血管造影检查结果，主要的改变为视乳头低荧光和视网膜毛细血管无灌注区。图形视觉诱发电位检查发现，83．3％出现振幅降低和（或）潜伏期延长。分别用糖皮质激素治疗、高压氧、高压氧联合糖皮质激素、视网膜激光光凝等治疗，只有10只眼（16．4％）视力有不同程度的改善。结论RON潜伏期变异大，造成的视力和视野损伤重，视功能预后极差，主要眼部损伤为视网膜血管闭塞和不同程度视神经萎缩。目前针对并发症的保守治疗能短期改善视力。

Objective To investigate the clinical features, risk factors, diagnostic methods, treatment regimens and outcomes of Chinese adult patients with radiation optic neuropathy （RON）. Methods Retrospective case series. Clinical data with RON admitted to Zhongshan Ophthalmic Center from June 1999 to October 2010 were investigated retrospectively. Results Thirty-five cases （61 eyes） with RON were analyzed. All cases manifested as sudden binocular or monocular painless vision decrease. In 18 cases （51.4%）, symptoms occurred within 36 months after the completion of radiation. In 43 eyes （70. 5% ） , the visual acuity was less than 0. 05 and/or with a visual field less than 10 degrees. In 52 eyes which the fundus could be examined, 41 eyes （78.8%） showed a clear boundary of optic papilla, including 6 eyes （ 14. 6% ） with normal appearance of optic papilla, 30 eyes （ 73.2% ） with lighter color, 5 eyes （12. 2% ） with pale optic papilla, and 11 eyes （21.2%） with edematous or hemorrhagic and/or exudative optic papilla. Only 14 eyes showed abnormal visual field examination, mainly manifested as nerve bundle defect scotoma. Seven eyes （50%） manifested as arcuate scotoma, 3 eyes （21.4%） manifested as central scotoma and /or paraeentral scotoma, 2 eyes accompanied by blind spot enlargement, 1 eye showed paracentral scotoma and 1 eye with quadrantanopia. Twenty-three eyes received fluorescein angiography （FFA）, the major manifestations were low fluorescence at the optic nerve and areas of capillary nonperfusion. Pattern visual evoked potential revealed reduced amplitude and/or extended incubation period in 83.3% eyes. Treatment regimens including systemic corticosteroids, hyperbaric oxygen therapy, hyperbaric oxygen in combination with corticosteroid and laser photocoagulation, the visual acuity of 10 eyes （16.4%） had merely been improved. Conclusions The prognosis of visual function in RON is poor resulting from devastating visual loss and/or visual field defect. The main damage of the fundus is retinal vascular occlusion and optic atrophy at different degrees. No adequately effective therapies are proved currently. The treatment aimed on the complication could only provide a short-term improvement of the vision.