Abstract
Purpose :
To investigate inter-observer and inter-device agreement in gonioscopic evaluation analizing Gonio-Photography (GP) performed by a 360° automated indirect gonioscope.
Methods :
Two masked senior ophthalmologist with glaucoma expertise, evaluated GP taken by an automated indirect gonioscope prototype (NIDEK CO., Japan). Apparent iris insertion, pigmentation and the presence of abnormal findings were compared with slit-lamp gonioscopy. Inter-observer and inter-device agreement for apparent iris insertion and pigmentation were determined by using Cohen’s linearly weighted κ (KW) coefficient of concordance.
Results :
450 photos of 25 eyes were examined; inter-observer agreement in apparent iris insertion and pigmentation was 0,4 (95% CI 0,25 to 0,54) and 0,08 (95% CI -0,04 to 0,21) respectively. For iris-insertion, after grouping the angles as wide and narrow the agreement was 0,51 (95% CI 0,26 to 0,75). Inter-device agreement in apparent iris insertion and pigmentation was 0,56 (95% CI 0,45 to 0,67), 0,10 (95% CI 0,01 to 0,22) for Observer 1; and 0,35 (95% CI 0,23 to 0,49), 0,45 (95% CI 0,31 to 0,59) for Observer 2. Observer 1 had higher agreement with gonioscopy than Observer 2, for iris insertion, after grouping the angles as wide and narrow, 0,92 (95% CI 0,82 to 1,0) and 0,56 (95% CI 0,31 to 0,81). The image quality was indirectly proportional to the agreement.
Both observer identified anterior chamber angle (ACA) abnormalities, i.e. peripheral anterior synechiae (PAS), iridectomy, internal ostium of trabeculectomy, Xen® device, EX-PRESS® device, draining tube, anterior chamber IOL haptics and iris snake vessels.
Conclusions :
Gonioscopy is an essential part of the eye examination, crucial to the diagnosis and classification of glaucoma. Our data suggest that GP is more difficult to interpret for cases of deeper iris insertion. GP using the NIDEK GS-1 Automated Gonioscope prototype (NIDEK CO., Japan) is a well-tolerated, quick and useful method for recording photographically apparent iris insertion, pigmentation, pathological and post-operative ACA findings in glaucoma patients. Intra-image quality over 360° is being addressed.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.