脉络膜黑色素瘤局部放射治疗后黄斑部视网膜脉络膜血流变化的研究

Longitudinal detection of radiation-induced macular retinal and choroidal capillary density changes with OCT angiography in choroidal melanoma

目的使用相干光断层扫描血流成像(OCTA)技术动态观察巩膜放射敷贴治疗前后脉络膜黑色素瘤患者黄斑区视网膜及脉络膜血流密度的变化情况,探索放射性视网膜病变(RR)发生前的眼部血流变化情况。设计前瞻性队列研究。研究对象2017年5月至2018年7月诊断为脉络膜黑色素瘤并进行碘125(125I)巩膜放射敷贴治疗的患者30例。方法患者在进行125I巩膜放射敷贴治疗前,及治疗后取出敷贴器后1天,敷贴治疗后1、3、6、12个月进行OCTA检查。观察视网膜及脉络膜血流变化,并采用多因素线性回归分析视力与OCTA测量指标的相关性。主要指标最佳矫正视力,黄斑区视网膜厚度,黄斑中心凹周围浅层视网膜及深层视网膜血流密度,中心凹无血管区(FAZ)面积,FD-300血流密度,FD-300长度密度及脉络膜毛细血管血流密度。结果敷贴治疗前,与对侧未受累眼相比,脉络膜黑色素瘤患眼的黄斑区视网膜明显增厚(P=0.004),中心凹周围浅层(P=0.05)和深层视网膜(P<0.001)血流密度均有所降低,FAZ面积降低(P=0.002),FD-300血流密度(P<0.001)、FD-300长度密度(P=0.042)及脉络膜毛细血管血流(P=0.001)均显著降低。12个月随访期间,随时间延长,FD-300血流密度(P<0.001)和长度密度(P=0.007)逐渐降低。随着时间延长,浅层视网膜血流密度逐渐降低,而脉络膜毛细血管血流密度则表现为先升高后降低的趋势,但无统计学意义(P均>0.05)。巩膜放射敷贴治疗前,患眼视力与肿瘤距视盘距离(P=0.006)和距黄斑距离(P=0.021)显著相关,即距离视盘和黄斑越远,视力越好。巩膜放射敷贴治疗后1个月,在矫正了年龄和肿瘤距视盘距离后,患眼最佳矫正视力与黄斑中心厚度(CMT)呈显著负相关。结论脉络膜黑色素瘤患者在接受巩膜放射敷贴治疗以前就已经发生了视网膜和脉络膜血流的改变,敷贴治疗后随着时间延长,浅层视网膜血流密度逐渐降低。RR发生前就已经存在视网膜血管的改变,这对于RR的诊断和治疗时机选择提供新的依据。

Objective To study longitudinal changes in retinal and choroidal capillary circulation in eyes treated with iodine 125(125I)plaque brachytherapy for uveal melanoma with OCT angiography(OCTA),and to explore changes in ocular blood flow before radiation retinopathy(RR).Design Prospective cohort study.Participants 30 patients diagnosed with choroidal melanoma from May 2017 to July 2018 and underwent 125I scleral radiotherapy.Methods Patients underwent OCTA examinations before 125I plaque brachytherapy,1 day,1 month,3 months,6 months and 12 months after the surgery.Retinal vascular density and choroidal capillary density were measured respectively and the correlation between visual acuity and OCTA parameters were analyzed.Main Outcome Measures Best corrected visual acuity(BCVA),retinal thickness,vacular density of the superficial and deep retinal in parafovea area,foveal avascular zone(FAZ)area,FD-300 area density,FD-300 length density and choroidal capillary vascular density.Results Before plaque brachytherapy,compared with the contralateral uninvolved eye,the choroidal melanoma eyes had thicker central macular thickness(P=0.004),lower parafoveal vascular density in superficial(P=0.05)and deep(P<0.001)retinal layer,smaller FAZ area(P=0.002),lower FD-300 area density(P<0.001),lower FD-300 length density(P=0.042),and lower choroidal capillary density(P=0.001).Patients were followed up for up to 12 months and found that FD-300 area density(P<0.001)and length density(P=0.007)gradually decreased.Although without statistically significant(all P>0.05),the superficial retinal vascular density gradually decreased with time,while the choroidal capillary vascular density increase at first and then decreased.Prior to scleral radiation application,the visual acuity of the affected eye was significantly correlated with the distance of the tumor from the optic disc(P=0.006)and macula(P=0.021).Multivariate linear regression analysis showed that 1 month after scleral radiation application,after adjusting the age and the distance of the tumor from the optic disc,the BCVA of the affected eye was significantly negatively correlated with central macular thickness.Conclusion Patients with choroidal melanoma had undergone changes in retinal and choroidal blood flow before receiving scleral radiotherapy,and the superficial retinal blood flow density gradually decreased as time passed after the plaque brachytherapy.It suggests that there may have been retinal vascular changes before the occurrence of radiation retinopathy.The retinal vascular changes existed before the occurrence of RR,which provides a new basis for the diagnosis and treatment timing of RR.