The Application Of Slip-lamp Anterior Segment OCT In The Ocular Anterior Segment Examination

Object To understand the image characteristics of anterior segment structures by slit-lamp adapted OCT (optical coherence tomography, OCT) and analyze the biological parameters related with these structures obtained from patients with different degree of myopia. Methods Slit-lamp adapted OCT was used to image the anterior segment in adult patients younger than 40 years with different degree of myopia. We analyzed the characteristic of the image and obtain corresponding biological parameters for statistic analysis grouped by sex and degree of myopia. Results Slit-lamp adapted OCT could clearly display anterior segment structures,especially chamber angle. The difference being not significant among the three mearements obtained from the same structure of anterior segment indicaed that the data were repeatable and reliable. Chamber angles obtained from different positions within each sex group indicated that the superior chamber angles were narrower than nosal, temporal and inferior chamber angles (p<0.001) and the inferior chamber angles were broader than nosal and temporal chamber angles (p<0.05) for both sex groups. The nosal chamber angles were broader than temporal chamber angles in femal group but not for male group. The factor of sex and myopia had different effect on the parameters obtained from anterior segment. The effect of sex (F= 4.32,p<0.05), but not for degree of myopia (F=2.63,p>0.05), on CCT was significant. The effect of sex and degree of myopia on the other parameters, such as horizontal curvature, vertical curvature, chamber depth, chamber volume and nosal ACA free, was justly opposite. While these two factors had no effect on distance between sclera spurs. Conclusion Slit-lamp adapted OCT could clearly display the anterior segment and generate related biological parameters with better repeatability. The parameters of anterior segment changed differently with sex and degree of myopia. The chamber angles changed with positions. Objective To study the early changes in anterior segment after phacoemulsification and foldable IOL implantation with slit-lamp OCT. Methods Small-incision phacoemulsification and foldable IOL implantation were performed in 43 (45 eyes) senile cataract patients. We measured the anterior segment with the slit-lamp OCT preoperationally, one day and one week postopeartionally and analyzed the related biological parameters generated by the OCT. Results In all patients , the difference preoperationally and one day postoperationally was significant for central cornea thickness CCT(pre 559±63μm/post 527±48μm),anterior chamber distance ACD500(pre 2.74±0.43mm /post 2.14±0.53mm),angle opening distance AOD500 ( pre 0.512±0.231mm/post 0.283±0.156mm ) , trabecular-iris space area TISA500(pre 0.263±0.094mm2/post 0.189±0.132mm2)and anterior chamber angle ACA500(pre 48.46±15.34o /post 28.32±8.97o). The difference between one day and one week postoperationally was not found to be significant. Conclusion The anteriro segment OCT could be used to to measure quantitatively the anterior segment structure during early stage postcataract. The early chamber width and the effective filter areas increased post phacoemulsification and foldable IOL implantation...