Evaluation Of The Damage Of Optic Nerve After Acute Primary Angle Closure Glaucoma

Objective: To investigate the changes in thickness of retinal nerve fiber layer(RNFL)and visual fields following the initial acute attack of acute primary angle closure glaucoma(APACG)within 1 year,analyze the regularity of optic nerve damage.Methods:1 A total of 30 eyes of 30 consecutively recruited patients with APACG were observed(one is acute for the first time,the other one is preclinical eye).The attacked eye was chosen as the observed eye while the fellow eye was used as the control eye.2 At 6 time points(the acute attack,after intraocular pressure controlled for 1 week,1 month,3 months,6 months,12 months),ocular examination consisted of visual acuity,Intraocular pressure(IOP)determinate with a calibrated Goldman applanation tonomete,7 RNFL parameters(superior temporal,temporal,inferior temporal,superior nasal,nasal,inferior nasal and average RNFL thickness)measured with optical coherence tomography(OCT);At 5 time points(the acute attack,after intraocular pressure controlled for 1 month,3 months,6 months,12 months),ocular examination consisted of and glaucoma hemifield test(GHT),mean defect(MD)and pattern standard deviation(PSD)determined with Humphrey perimeter.3 Statistical analysis was conducted with SPSS 19.0.Result:1 The IOP was normal in the observed group after treatment within 12 months.2 The vision gradually increased in the observed group after the IOP recovered to normal within 1 month(P <0.05).After that,the vision keep stable(P> 0.05).3 In the control group,there were no significant differences between the 7 RNFL parameters at 6 time points(P> 0.05).4 Compared with the control group,the parameters of 7 RNFL in the observed group were thicker at the acutely attacked periods and the IOP controlled after 1 week(P <0.001).No remarkable change in the thickness of RNFL at the nasal,the superior temporal and the temporal was measured after the IOP controlled for 1 month between the control group and the observed group(P = 0.769,0.056,0.061),whereas there was a significant thin in the other RNFL of the observed group relative to the control group(P <0.05).Compared with the control group,the parameters of 7 RNFL in the observed group were thinner after the IOP controlled for 3 months,6 months and 12 months.5 In the observed group,there was no significant difference in the thickness of RNFL at the nasal and the temporal between the acute attack and the IOP controlled for 1 week(P = 0.078,0.156),whereas there was a significant thin in the thickness of the other RNFL(P <0.05).After the IOP controlled for 3 months,the thickness of 7 RNFL was gradually decreased and the changes was significant(P <0.05).the thickness of the RNFL in the inferior nasal,the inferior temporal and the average was thinner after the IOP controlled for 6 months compared with the IOP controlled for 3 months,and the change in the other RNFL was not significant(P> 0.05).The alternation of the 7 RNFL was not notable after the IOP controlled for 12 months relative to the IOP controlled for 6 months(P> 0.05).6 In the observed group,the visual field defect was 80%,67%,60%,60%,63% at the acutely attacked periods,the IOP controlled after 1 month,3 months,6 months and 12 months respectively;The MD was greatly increased and the PSD was markedly decreased after the IOP controlled for 1 month compared with the acute attack(P=0.038).After that,the change in the MD and PSD was not significant(P> 0.05).7 In the observed group,the thickness of averaged RNFL was not correlated with the MD(P> 0.05)at the acute attack;The thickness of averaged RNFL was positively correlated with the MD at the IOP controlled after 1 month,3 months,6 months and 12 months respectively(P <0.05).8 In the observed group,the difference in the RNFL and the MD was not correlated with the maximum of the IOP at the acute attack and the IOP controlled for 12 months.There was no correlation between the duration of high IOP at the acute attack and the average RNFL and MD;After the IOP controlled for 12 months,the duration of high IOP was negatively correlated with the average RNFL and MD(P <0.05).Conclusion:1 The thickness of the RNFL in patients with APACG is diffusely increasing after the acute attack for the first time,which is gradually thinner with the time going.However,it is stable after IOP controlled for 6 months and there is no significant change in the thickness of the RNFL at the end of the 12 months.2 The visual field in patients with APACG is damaged after the acute attack for the first time,which is better after the IOP controlled for the 1month,and there is no deterioration until the 12 months.3 The damage is earlier for the RNFL than the visual field defect in patients with APACG after the first acute attack.4 For the optic nerve,the injury of morphology is consistent with the function in patients with APACG after the first acute attack.5 The thickness of average RNFL and the MD of visual field are negatively consistent with the continuation of the high IOP in patients with APACG after the IOP controlled for 12 months.It is very important to quickly reduce the IOP for patients with APACG after the acute attack.