Purpose To demonstrate that it is capable to measure the ocular dimensions in vivo using dual channel whole eye optical coherence tomography(OCT) in comparison with IOL Master.
Methods Enrolled were 39 eyes of 21 volunteers aged 21 to 35 years and without history of ocular disease. A custom-built dual focus dual channel spectral domain optical coherence tomography (SD-OCT) was used to obtain simultaneously image of the whole eye surfaces from the cornea to the retina. Corneal curvature(CC,anterior corneal surface curvature), anterior chamber depth(ACD) ,the thinkness of the len,the center curvature of the anterior Total axial length (AL,from the corneal apex to the retinal pigment epithelium) were measured two times with the dual channel full eye OCT and IOL Master independently.
Results the OCT images of the the whole eye surfaces,including the cornea,the antierior and posterior surfaces of the lens and the retina,were successfully accessed in real time(figure 2).The mean corneal thickness from 39 eyes of SD-OCT measurement was 0.5530±0.0159mm,antierior chamber depth 3.64±0.20mm,lens thinkness 4.68±0.30mm, anterior lens surface curvature 9.36±0.27mm and total axial length was 25.32±0.64mm.No significant differences were found between measurements of the two different days(P>0.05,paired t-test).The mean antierior chamber depth of the measurements of the IOLMaster was 3.58±0.21mm and total axial length was 25.31±0.65mm. There was statistically significant difference between the SD-OCT and IOLMaster measurements of the antierior chamber depth(P<0.001, paired t-test) but no significant difference of total axial length(P=0.468, paired t-test). The 95%LOA was +0.004mm to +0.118mm for measurement of ACD,and was -0.223 to +0.251 for measurement of AL by the SD-OCT and IOLMaster. There were high correlations(antierior chamber depth r=0. 990,p<0.001,figure 3 and total axial length r=0.982, p<0.001,figure 4) of the two devices.
Conclusions By dual channel whole eye OCT,the image of whole eye surfaces and repeatable measurements of the ocular dimensions were obtained. This newly technique offers a new noncontact method for ocular dimensions measurement that may be great helpful of the research on accommodation and myopia.