OCT测量RNFL厚度在PACG早期诊断中的应用

目的：探究频域光学相干断层成像技术(optical coherence tomography，OCT)测量视网膜神经纤维层(retinal nerve fiber layer，RNFL)厚度在原发性闭角型青光眼(primary angle-closure glaucoma，PACG)早期诊断中的应用。

方法：本次研究对象为2015-04/2017-04于我院诊断与治疗PACG患者100例174眼，根据视野损伤程度由轻到重分为早期组(30例50眼)、进展组(45例78眼)与晚期组(25例46眼)； 同时选择年龄、性别配对的健康体检人员30例60眼，设为对照组。入组后进行常规检查； OCT检查平均RNFL厚度，采用全自动视野计检查各组视野情况，分析RNFL厚度与视野平均缺损(mean defect，MD)相关性，并比较各组上、下、鼻侧、颞侧各象限RNFL厚度。

结果：四组入试者平均RNFL厚度差异具有统计学意义，对照组显著高于PACG患者组，早期组显著高于进展组与晚期组，进展组显著高于晚期组，差异均具有统计学意义(P<0.05)； 四组入试者视野MD差异具有统计学意义，对照组显著低于PACG患者组，早期组显著低于进展组与晚期组，进展组显著低于晚期组，差异均具有统计学意义(P<0.05)； 早期组、进展组和晚期组RNFL厚度与视野MD呈负相关(r=-0.546、-0.654、-0.864，均P<0.05)，对照组RNFL厚度与视野MD无相关性(r=-0.075，P=0.321)； PACG患者上方、下方RNFL厚度显著低于对照组，差异具有统计学意义(P<0.05)，进展组与晚期组鼻侧、颞侧RNFL厚度显著低于对照组，差异有统计学意义(P<0.05)，早期组与对照组鼻侧、颞侧RNFL厚度差异无统计学意义(P>0.05)。

结论：随着病情加重PACG患者RNFL逐渐变薄，RNFL与视野MD呈负相关，RNFL能够客观反映PACG视神经损害程度，检测上方、下方RNFL厚度对PACG早期诊断具有一定的运用价值。

Application of optical coherence tomography measuring RNFL thickness in the early diagnosis of primary angle-closure glaucoma

AIM: To investigate the application of optical coherence tomography(OCT)measurement of retinal nerve fiber layer(RNFL)thickness in early diagnosis of primary angle closure glaucoma(PACG).

METHODS:Totally 100 patients(174 eyes)with PACG treated in our hospital from April 2015 to April 2017 were selected and divided the into early stage group(30 cases, 50 eyes), mild stage group(45 cases, 78 eyes)and late stage group(25 cases, 46 eyes)according the degree of the visual field defect. At the same time, 30 patients(60 eyes)with matched age and sex were included into control group and received routine examination. The OCT was used to check the average RNFL thickness, and the visual field was examined by automatic vision method. The correlation between RNFL thickness and mean defect(MD)was analyzed, then the thickness of RNFL in the superior, inferior, nasal and temporal quadrants of each group were measured.

RESULTS: The difference of mean RNFL thickness between the four groups was statistically significant, the RNFL thickness in control group was significantly higher than that of the PACG group, and the early stage group was significantly higher than the mild stage group and the late stage group, while the mild stage group was significantly higher than the late stage group, the difference was statistically significant(P<0.05). The difference of visual field MD between the four groups was statistically significant, the visual field MD in control group was significantly lower than that of the PACG group, and the early group was significantly lower than the mild stage group and the late stage group, while the mild stage group was significantly lower than the late stage group, the difference was statistically significant(P<0.05). The thickness of RNFL in the early stage group, the mild stage group and the late stage group was negatively correlated with visual field MD(r=-0.546, r=-0.654, r=-0.864, P<0.05). There was no correlation between the RNFL thickness and the visual field MD in the control group(r=-0.075, P=0.321). The thickness of RNFL in the superior and inferior part of PACG group was lower than that of the control group, and the difference was statistically significant(P<0.05). The thickness of the nasal and temporal RNFL in the mild stage group and the late stage group was significantly lower than that in the control group(P<0.05). There was no significant difference in the nasal and temporal RNFL between the early stage group and the control group(P>0.05).

CONCLUSION: RNFL of PACG patients is gradually thinning with the exacerbations; RNFL is negatively correlated with visual field MD, and RNFL is able to objectively reflect the degree of PACG optic nerve damage. The detection of the superior and inferior RNFL thickness had a certain value in the early diagnosis of PACG.