Association of peripheral anterior synechia,intraocular pressure,and glaucomatous optic neuropathy in primary angle-closure diseases

AIM:To investigate the association of peripheral anterior synechiae(PAS)with intraocular pressure(IOP)and glaucomatous optic neuropathy(GON)in primary angle closure(PAC)and primary angle-closure glaucoma(PACG).METHODS:Totally 355 eyes(238 PAC and 117 PACG)of 181 patients were included in this retrospective analysis of baseline data from a randomized clinical trial.All patients had undergone a comprehensive ophthalmic examination.The extent of PAS in clock hours as determined on gonioscopy was documented.The independent effect of the extent of PAS on IOP and the prevalence of GON were determined using multivariable generalized estimating equation(GEE)models.RESULTS:The frequency of GON increased with the extent of PAS and a higher IOP.PAS were more extensive(8 vs 1 clock hour,P<0.001)and IOP higher(28.01 vs 18.00 mm Hg,P<0.001)in PACG compared to PAC.The prevalence of GON among the PAS quartiles were 10.2%(PAS<0.5 clock hours),16.9%(PAS≥0.5 and PAS<3 clock hours),29.6%(PAS≥3 and PAS<7 clock hours),and 74.4%(PAS≥7 clock hours),respectively.After adjusting for IOP,age,gender,spherical equivalent,average Shaffer score and number of medications,the odds ratio(OR)for GON was 4.4(95%CI:1.5-13.0;P=0.007)with PAS≥3 clock hours and 13.8(95%CI:4.3-43.6;P<0.001)with PAS≥7 clock hours as compared to eyes with PAS<0.5 clock hours.The frequency of GON increased linearly with the extent of PAS.Extent of PAS was also associated with higher IOP.Eyes with both PAS≥6 clock hours and IOP≥21 mm Hg had the highest risk of GON compared to eyes with both PAS<6 clock hours and IOP<21 mm Hg(OR=18.0,95%CI:7.5-43.4;P<0.001).CONCLUSION:The extent of PAS in PAC and PACG is an important predictor of higher IOP and is linearly associated with GON independent of IOP,suggesting other factors related to PAS formation may be involved in the development of GON in PACG.

Morphological features of anterior segment:factors influencing intraocular pressure after cataract surgery in nanophthalmos

Purpose:To investigate the anterior segment in nanophthalmic eyes and their association with intraocular pressure after cataract surgery.Methods:Thirty-two nanophthalmic eyes(axial length[AL]<18.5 mm)in 18 patients and 35 normal eyes(21.0≤AL≤24.5 mm)in 35 controls who had undergone uneventful cataract surgery were included.Swept-source optical coherence tomography was used to compare the anterior segment structures between the two groups.The associations between the anterior segment characteristics of nanophthalmic eyes and postoperative intraocular pressure(IOP)were also investigated.Results:The IOP-lowering effect of cataract surgery was remarkably insufficient in nanophthalmic eyes.Peripheral anterior synechiae(PAS)were observed in 56%(18/32)of nanophthalmic eyes,and a characteristic boomerangshaped iris was observed in 28%(9/32).The anterior surface of the iris seemed"smoother"in nanophthalmic eyes than in normal eyes.Schlemm's canal(SC)diameter,SC area,trabecular meshwork(TM)thickness,TM width,and TM area were generally smaller in the nanophthalmic eyes.Younger age,higher preoperative IOP,broader PAS,and smaller SC area were main contributors to higher postoperative IOP.AL and SC diameter may also be of great importance in IOP prediction in patients without glaucoma surgery and PAS.Conclusions:The morphological features of the anterior segment in nanophthalmic eyes are significantly different from those of normal eyes.Influencing factors such as age,AL,preoperative IOP,extent of PAS,SC and TM size could all be prognostic for IOP after cataract surgery in nanophthalmic eyes.Trial registration:ClinicalTrails.gov,Trial registration number:NCT02182921,Registered 8 July 2014.

Long-term intraocular pressure fluctuation of primary angle closure disease following laser peripheral iridotomy/iridoplasty

Background Many studies indicated that short-term and long-term intraocular pressure （IOP） fluctuations in primary open angle glaucoma patients might lead to glaucomatous progression. However, seldom study has evaluated the long-term fluctuation of IOP in primary chronic angle closure diseases. The objective of this study was to investigate the long-term IOP fluctuation of primary angle closure diseases and its associations following laser peripheral iridotomy （LPI） with or without laser peripheral iridoplasty.Methods A total of 158 patients with primary angle closure suspect （PACS, n=21）, primary angle closure （PAC, n=81） and primary angle closure glaucoma （PACG, n=55） had been treated by LPI with or without laser peripheral iridoplasty and followed up for more than 12 months. IOP was measured with Goldman applanation tonometer. Multivariate linear regression with generalized estimating equation （GEE） regression models was used to evaluate the association of long-term IOP fluctuation （maximum IOP minus minimum IOP） with gender, age, baseline IOP, baseline peripheral anterior synechia （PAS）,baseline vertical cup/disc ratio （VCDR）, baseline mean deviation （MD）, need for IOP-lowering medications.Results IOP fluctuation during follow-up in PACS, PAC and PACG groups were （4.83±2.90）, （5.67±3.35）, and （9.40±7.14）mmHg, respectively. IOP fluctuation was strongly correlated with baseline IOP （r=0.356, P 〈0.001）, PAS （r=0.374, P 〈0.001）.IOP fluctuation was higher in patients with higher baseline IOP （0.18 mmHg per unit increase, 95% CI： 0.05-0.31 mmHg）.Conclusions Long-term IOP fluctuation in PACG group was larger than that in PACS or PAC group. Eyes with higher baseline IOP were observed to have larger long-term IOP fluctuation.