The Change Of The Ciliary Body Parameters In Eyes With Acute Primary Angle Closure.

Objective To investigate the differences of biometric measurements between hui and han people and to investigate the change of the ciliary body parameters among the patients with acute primary angle closure（APAC）,follow eyes and normal controls.Methods Case-control study.Fifty-five consecutive patients diagnosed with APAC in one eye were presented from Ningxia Eye Hospital as case groups（25 cases of hui nationality and 30 cases of han nationality）.Meanwhile,55 eyes from fifty-five age-matched normal controls were recruited（22 cases of hui nationality and 33 cases of han nationality）.All cases were taken general eye examination including intraocular pressure（IOP）,gonioscopy,slit-lamp examination with a 90-diopter and visual field examination.Besides,A-scan ultrasonography and UBM were conducted to determine biometric measurements including axial length（AL）and lens thickness（LT）and ciliary body parameters including maximum ciliary body thickness（CBTmax）,ciliary body thickness at point of the scleral spur（CBT0）and 1000 um from the scleral spur（CBT1000）,anterior placement of ciliary body（APCB）,and trabecular–ciliary process angle（TCA）respectively.Statistical analysis was performed using SPSS software version 17.0.Paired t-tests were used to evaluate the differences between case groups.Independent t-tests to evaluate the differences between case group and normal controls and the differences between different nationality from normal controls in ocular biometric parameters.The correlation analysis between biometric measurements and ciliary body parameters were evaluated by Pearson correlation analysis.ResultThe differences in biometric measurements and ciliary body parameters between hui and han were not statistically significant（P>0.05）in normal controls.In eyes with APAC,their fellow eyes and normal eyes,average CBTmax were 0.907±0.106,0.960±0.098and 1.020±0.108mm,respectively.Average CBT₀ were 0.770±0.123,0.811±0.135 and0.852±0.142mm,respectively.Average CBT₁₀₀₀000 were 0.541±0.103,0.568±0.086 and0.619±0.093mm,respectively.Average APCB were0.647±0.175,0.669±0.186and0.402±0.144mm,respectively.Average TCA were48.99±11.48°,51.32±10.87°and81.94±12.45°,respectively.Compared with the fellow eyes,higher intraocular pressure（IOP）,wider peripheral anterior synechia（PAS）,larger cup-to-disc（C/D）ratio and worse visual field indices were observed in eyes with APAC and the differences were statistically significant（P<0.001）.Parameters including shalloweranterior chamber depth（ACD）,larger pupil diameter（PD）and thicker lens thickness were showed as well in eyes with APAC（P<0.001,P=0.001,P=0.011）.In addition,CBTmax,CBT0,CBT1000 were thinner and TCA were smaller compared with their fellow eyes（P<0.001,P=0.001,P=0.001,P=0.013）.Compared with the normal eyes,wider PAS,worse visual field indices were observed in fellow eyes and the differences were statistically significant（P=0.000-0.008）.Parameters including shallower ACD,smaller AL were showed as well in fellow eyes（P<0.001,P<0.001）.In addition,CBTmax,CBT0,CBT1000 were thinner（P<0.001,P=0.002,P<0.001）,TCA was smaller whereas APCB was lager compared with the normal eyes（P<0.001,P<0.001）.In correlation analysis,positivecorrelationsbetweenALandCBT₁₀₀₀/TCAwerefound（r=0.335-0.380,P=0.004-0.012）but negative correlations between IOP and CBTmax（r=-0.289,P=0.032）.Conclusions（1）There was no significant difference in ocular biometric parameters between hui and han nationality in this study.（2）Compared with their fellow eyes and normal controls,higher IOP,wider peripheral anterior synechia and worse visual field indices were observed in eyes with APAC.（3）Compared with the normal eyes,parameters including smaller AL,shallower ACD and more anteriorly ciliary body were showed in the eyes with APAC and their fellow eyes.（4）In this study,AL correlated positively with CBT₁₀₀₀000 and TCA while IOP correlated negatively with CBTmax.（5）More research will be needed in the future to explore the differences in ocular biometric parameters between different nations and to explore the relationship between ciliary body parameters and mechanism of APAC.