The Study Of CASIA SS-1000 OCT On The Biological Morphology Of Schlemm’s Canal

Objective: Glaucoma(Glaucoma)is one of the most common worldwide progressive,irreversible damage to visual function of eye disease,the disease has the characteristic of optic nerve injury and vision,as the world’s second largest blinding eye disease.Primary open Angle glaucoma(Primary open Angle glaucoma,POAG)is a common type of glaucoma,mechanism is not yet clear,but in the pathogenesis of POAG,elevated iop aqueous humor circulation caused by blocked this mechanism has been recognized by people,and is a hotspot of current research.Many scholars previously done a lot of research on mechanism of POAG animals and animal experiment,shows that anterior chamber Angle of Schlemm’s pipe in the form of biological change is likely to be the main cause of the aqueous humor blocked.To study the differences in the biological morphology of the Schlemm’s canal between patients with primary open angle glaucoma(POAG)and normal subjects through imaging by the latest and dedicated anterior segment examination imaging device,the CASIA SS-1000 type of anterior segment scanning optical coherence tomography(OCT);to confirm the morphological changes of Schlemm’s canal in normal subjects and the related influencing factors;thus to further understand whether it can have a clear imaging of the Schlemm’s canal and play an important role in POAG development whether it could be used as a method of POAG early diagnosis.Methods: POAG patients admitted in the Department of Ophthalmology and Inpatient Department of the Second Affiliated Hospital of Da Lian University Second Hospital from January 2015 to April 2016 were enrolled in group A;at the same time,in physical examination center in our hospital who met the group criteria were enrolled in group B.All subjects have signed informed consent.All subjects underwent optometry,visual acuity(naked eye or corrected visual acuity),intraocular pressure,slit lamp,funduscopy,visual field,optic disc OCT and CASIA SS-1000 anterior segment scanning OCT examination.CASIA SS-1000 anterior segment scanning OCT was performed in group A and B with a clear imaging on the temporal and nasal orientation of the Schlemm’s canal at 8:00 am-9:00 am,Group A successful Schlemm’s image for A1 group,group B successful Schlemm ’s image for B1 group.Measure and compare the A1 and B1 group clear temporal and nasal side Schlemm ’s image.the temporal sectional cross area(TSCa),temporal sectional cross perimeter(TSCp),temporal sectional cross length(TSCl),nasal sectional cross are(NSCa),nasal sectional cross perimeter(NSCp)and nasal sectional cross length(NSCl)of Schlemm’s canal in both groups were calculated and compared;Collect group B1 study normal controls Schlemm ’s correlation data complete tube and its influence factors of the object of study the group B2,discussing the correlation between SCa,SCp,SCl of the Schlemm’s canal on two orientations and gender,age,anterior chamber depth,anterior chamber width,corneal thickness and refractive status;SPSS18.0 software was used for statistical analysis,the comparison between the two groups was based on the rank sum test,scores were used for χ2 test,SCa,SCp,SCl of Schlemm’s canal and some influencing factors were used for correlation analysis.Result:1.In this study,a total of 308 eyes who met the inclusion criteria were enrolled,there were 108 eyes in group A and 200 in group B;there were no significant differences in age,gender,corneal thickness and refractive status between the two groups(P> 0.05);there were significant differences in the fundus Cup/Disk and intraocular pressure between the two groups(P <0.05).2.The number of observed Schlemm’s canal on the temporal orientation in group A and B by CASIA SS-1000 anterior segment scanning OCT was 50(46%)and 108(54%),respectively;and 57(53%),120(60%)on the nasal orientation,respectively.The detection rate of observed Schlemm’s canal on the temporal and nasal orientation in group A and B were tested by chi square test,the result was P>0.05 with no statistical difference.The results of the comparison of TSCa,TSCp,TSCl,NSCa,NSCp and NSCl of Schlemm’s canal in both groups found that there were significant differences in the TSCa(z=-8.518,p=0.000),NSCa(z=-8.636,p=0.000),TSCp(z=-8.804,p=0.000),NSCp(z=-8.804,p=0.000),NSCl(z=-8.408,p=0.000)and TSCl(z=-8.208,p=0.000)between the two groups.3.In B2 group,the correlation between TSCa,NSCa,TSCp,NSCp,TSCl,NSCl in group D and gender,age,anterior chamber depth,anterior chamber width,corneal thickness and refractive status were investigated,results found that there was significant differences between the refractive status with P < 0.05,TSCa(r=0.414,p=0.002)and TSCl(r=0.308,p=0.027).There had no differences in corneal thickness,gender,age,anterior chamber depth and anterior chamber width.Conclusion:1.CASIA SS-1000 anterior segment scanning OCT can be used to image and accurately measure the Schlemm’s canal on temporal and nasal orientation of POAG patients and normal subjects.2.SCa,SCp and SCl of Schlemm’s canal on temporal and nasal orientation of POAG patients were significantly decreased compared with those in normal subjects.3.There had a correlation between Schlemm’s canal on temporal orientation and SCa,SCl and had not notable correlation between Schlemm’s canal on nasal side and SCa,SCl,as well as refractive status in normal subjects.4.The morphology change of Schlemm’s canal is one of the pathogenesis of POAG,which played a role in the mechanism of pathogenesis and development of the disease.