Session Title: Free Paper Session 15: Mixed Session
Session Date/Time: Friday 08/09/2017 | 16:30-18:00
Paper Time: 17:36
Venue: Room 117
First Author: : A.Papayannis ITALY
Co Author(s): : E. Tsamis D. Bonsanto F. Foltran F. Pellegrini P. Stanga G. Prosdocimo
To assess the ability of Swept Source Optical Coherence Tomography (SS-OCT) Biometry in detecting foveal vitreoretinal and choroidal lesions during routine preoperative assessment for cataract surgery alone or combined with vitreoretinal surgery.
Observational, prospective, cross-sectional study. A total of 410 phakic eyes from 301 consecutive patients that underwent routine preoperative assessment with Zeiss IOL Master SS-OCT Biometry for cataract surgery alone or combined with vitreoretinal surgery were included in the study.
Zeiss IOL Master 700 SS-OCT Biometry, commercially available system, was used to scan both eyes, when the fellow eye was phakic, as part of the routine preoperative assessment for cataract surgery alone or combined with vitreoretinal surgery. All the patients with signs of foveal lesions on SS-OCT Biometry scan or during slit lamp fundus examination also underwent conventional Heidelberg Blue Peak Spectral Domain OCT (SD-OCT) examination. Qualitative comparison of SS OCT Biometry foveal scans with SD-OCT macular scans was performed from two independent reviewers.
We found signs of foveal lesions on both SS-OCT Biometry and conventional SD-OCT in 46/410 eyes with 100% inter-reviewer agreement. 15 over 46 eyes present signs of Macular Hole or Epiretinal Membrane (ERM), 6 macula off Retinal Detachment (RD), 10 Macular Edema due to diabetes or vein occlusion, 13 signs of choroidal neovascularization (CNV) or advanced dry AMD, 2 presence of subretinal lipofuscin deposits due to Pseudobest. In other 14 eyes conventional SD-OCT highlighted presence of macular lesions as CNV and ERM, not detectable with the foveal SS-OCT Biometry scan as localized outside the small scanning area. In 3 patients we were unable to obtain adeguate foveal scans due to poor foveal fixation or presence of stable extrafoveal fixation caused from atrophic or fibrotic damage of the fovea in AMD. Motion artefacts were observed in 26 patients, with (5/26) or without (21/26) maculopathy. A repetition of the scan was sufficient to obtain an image with adequate quality in those patients. In all 6 patients with macula off RD, SS-OCT Biometry was able to automatically detect the retinal pigment epithelium plane and perform the Axial Length (AL) measurement automatically on this plane, avoiding AL calculation errors.
Zeiss IOL Master 700 is an instrument created to perform Biometry. The SS-OCT foveal scan aims to highlight the correct alignment of the optical axis during the AL measurement. The quality and the position of these scans depends on fixation. Scans are localized only on a single axis with a small field of scan that investigates only the foveal and juxtafoveal area. Despite that the currently commercially available SS-OCT Biometry has several limitations to investigate the retina in comparison to the conventional SD or SS-OCT that is the golden standard technique. Its ability to visualize vitreoretinal foveal alterations with the same quality of signal from the vitreous to the choroid and sclera, makes it a promising tool for assessing and screening vitreoretinal foveal and juxtafoveal diseases, predicting risk of reduced visual recovery and detecting contraindications to cataract surgery or indications to combined vitreoretinal surgery in most of the macular diseases. Further development of this instrument with a wider and multiple axis scans associated with a fundus camera could be helpful in the future in order to permit safer and easier diagnosis and screening of macular diseases during cataract routine preoperative assessment.