The Comparative Study of the Results of Visualization of the Anterior Chamber Angle of the Eye in the Primary Angle Closure Disease and Primary Open Angle Glaucoma

Purpose. To compare the iridotrabecular contact (ITC) parameters in patients with primary angle closure disease (PACD) and primary open angle glaucoma (POAG) based on SS-OCT data, and examine their relationship with other clinical and anatomical parameters. Patients and methods. The retrospective study analyzed the data of 89 patients aged 32 to 89 years: 43 patients with PACD, 25 with POAG, and 21 controls. All participants underwent optical coherence tomography of the anterior segment of the eye using the SS-OСT “CASIA2” (Tomey Corporation, Nayoga, Japan), including assessment of the ITC Index and ITC Area. Results. ITC parameters in PACD were significantly higher than in POAG and controls. ITC Index = 45.40 ± 21.80 % and ITC Area = 5.81 ± 3.90 mm 2 in the POAG group versus 0.01 ± 0.03 % and 0.1 ± 0.37 mm 2 in POAG, respectively, and versus 0.05 ± 0.11 % and 0.56 ± 1.17 mm 2 in the control, respectively, all p = 0.00. The values of ITC Index, as well as ITC Area in POAG and control were comparable, p = 0.21 and p = 0.25, respectively. A relationship was found between ITC Index and ITC Area in case of PACD with the depth of the anterior chamber ( r = –0.42, p = 0.01 and r = –0.43, p = 0.00, respectively), the lens vault ( r = 0.35, p = 0.02 and r = 0.36, p = 0.02, respectively), its thickness ( r = 0.47, p = 0.01 and r = 0.44, p = 0.01, respectively) and the number of antihypertensive drugs ( r = 0.63, p = 0.01 and r = 0.68, p = 0.01, respectively). No correlations were found in the POAG and control groups. Conclusion. The high values of the parameters of the ITС and their correlation with other clinical and anatomical parameters in PACD compared with those in POAG indicate the role of the topography of the anterior segment of the eye in the formation of the leading mechanisms for the anterior angle closure.