Measurement And Analysis Of The Characteristics Of Ciliary Body In Primary Acute Angle Closure Glaucoma

Objective:Primary angle-closure glaucoma(PACG)is the most common type of glaucoma in China.There are obvious differences in the anatomical structure of anterior segment between patients and normal people,including shorter axis,shallower anterior chamber,narrower angle,thicker lens and relatively anterior lens.Among them,acute angle-closure glaucoma(AACG)is a common clinical emergency in ophthalmology.The attack of acute angle-closure glaucoma(AACG)is sudden,and the iris quickly covers the trabecular meshwork,resulting in sudden closure of most or all of the anterior chamber angle,obstruction of aqueous humor discharge,and sharp and substantial increase of intraocular pressure.If not treated in time,it can lead to serious visual impairment,short-term visual impairment or even blindness.In recent years,more and more attention has been paid to the influence factors of angle closure caused by the changes of ciliary body morphology,including its position and shape.At present,some scholars have measured and analyzed the parameters of ciliary body morphology and anatomical position by ultrasound biomicroscopy(UBM).It is found that the abnormal position and thickness of ciliary body may play a role in the pathogenesis of PACG.However,according to previous studies,it is not clear that the sudden closure of chamber angle and acute attack of glaucoma can be explained.The reasons for the extension and the specific mechanism of the changes in ciliary body anatomy in the mechanism of angle closure are not fully understood.In this study,panoramic ultrasound biomicroscopy was used to observe and measure the changes of ciliary body morphological structure and position parameters in acute attack of primary angle-closure glaucoma at different time points under high intraocular pressure(IOP)and after IOP drop,so as to evaluate the role of ciliary body in acute attack of angle-closure glaucoma,in order to provide objective basis for the pathogenesis of AACG.Methods:This study included primary acute angle-closure glaucoma patients admitted to Handan Ophthalmological Hospital(the Third Hospital of Handan)from December 2016 to December 2017,and carried out outpatient follow-up observation.The criteria for admission were:(1)age over 40 years;(2)patients had two following symptoms: eye pain,headache,blurred vision,nausea and vomiting;(3)corneal edema,ciliary congestion,pupil dilatation;(4)shallow peripheral anterior chamber;(5)intraocular pressure > 40 mm Hg;(6)refractive state:-3.00D~+3.00D;(7)no previous history of acute major attack of angle closure glaucoma;(8)physical condition of the patients can cooperate with the completion of UBM examination.Case exclusion criteria:(1)secondary angle closure,such as secondary glaucoma caused by lens factors,uveitis,tumors,iris neovascularization and trauma;(2)patients with severe systemic diseases(cardiovascular and cerebrovascular diseases,respiratory diseases,tumors or other causes)can not tolerate UBM examination,or can not complete follow-up on time;(3)patients with other eye diseases;(4)Drugs affecting the relaxation of ciliary muscles have been used before consultation;(5)former eye laser therapy or intraocular surgery;(6)In addition to glaucoma surgery,other eye operations are needed;(7)pregnant or lactating women;(8)other clinical trials have been selected.According to the exclusion criteria,30 cases(60 eyes)were included in the study,of which 27 cases had uniocular seizures and 3 cases had binocular seizures.UBM and intraocular pressure were examined under binocular natural light in eligible patients during acute glaucoma attack,1 month and 6 months after intraocular pressure drop.The relative parameters of ciliary body morphology and structure in UBM images were measured and analyzed by measuring software.The measurement parameters include:(1)maximum ciliary body thickness(CBTmax)(2)ciliary body thickness at the scleral spur(CBT0)(3)ciliary body thickness at 1 mm posterior to the scleral spur(CBT1)(4)anterior placement of the ciliary body(APCB)(5)trabecular-ciliary process distance(TCPD)(6)iris-ciliary process distance(ICPD)(7)trabecular meshwork-ciliary angle(TCA)(8)trabecular meshwork-iris angle(TIA).All measurement data were analyzed and processed by SPSS20.0 statistical software,and the measurement data were expressed as(±s).The measurement data of acute attack eyes and contralateral eyes were tested by normality test,and the comparison between the two groups was made by independent sample t test after conforming to normal distribution.The parameters of ciliary body at two time points after acute attack and remission were compared by repeated measurement analysis of variance and Bonferroni method.Results:Thirty patients(60 eyes)were enrolled,of which 27 had uniocular seizures and 3 had binocular seizures.There were 26 females and 4 males,aged from 50 to 78 years,with an average age of 63.10 years.The intraocular pressure(IOP)of acute episodes was(50±5.85)mm Hg at the time of consultation,and(14.7±1.51)mm Hg at 1 month after remission,and(13.93±1.08)mm Hg at 6 months after remission.There were significant differences between the intraocular pressure of episodes and those of 1 month and 6 months after remission.The ACD measured in acute glaucoma attack was(1.73±0.21)mm,in 1 month after remission was(1.87±0.17)mm,and in 6 months after remission was(1.86±0.15)mm Hg.There were significant differences between acute glaucoma attack and ACD measured in 1 month and 6 months after remission.Compared with one month after remission,CBTmax,CBT0,APCB,ICPD,TCA and TIA had statistical differences(all P < 0.05).Compared with six months after remission,APCB,TCA and TIA had statistical differences(all P < 0.05).The intraocular pressure(IOP)of the patients with acute attack was(50 ±5.85)mm Hg and that of the contralateral eye was(16.56±4.76)mm Hg.There was a significant difference between the contralateral IOP and the attack period.The ACD of the acute attack eye was(1.73±0.21)mm and that of the contralateral eye was(1.96±0.38)mm.There was a significant difference between the two groups.The attack eye was shallower than that of the contralateral eye.There were significant differences in ACD,CBTmax,CBT0 and TIA between attack eyes and contralateral eyes(all P < 0.05).Conclusion:Primary angle-closure glaucoma with acute attack showed shallower anterior chamber,narrower anterior chamber angle,thinner ciliary body and more anterior relative position compared with the contralateral eye and after relief.Compared with the paroxysmal ciliary body at 1 month and 6 months after the attack of ocular remission,PACG has different degrees of variation in parameters.From the attack of paroxysmal phase to 6 months after remission,the ciliary body experienced a process of first thickening and thinning.