Best Practices for High-Quality Anterior Segment Optical Coherence Tomography Imaging of Eyes with the Port Delivery...

Background/Objectives: Anterior segment optical coherence tomography (AS-OCT) is a non-invasive imaging modality used to evaluate anterior segment features. This report aims to inform clinicians of best practices to obtain high-resolution AS-OCT images of anterior segment features of eyes implanted with the Port Delivery Platform (PDP). Methods: In PDP trials, AS-OCT imaging of the anterior segment was performed using Heidelberg Spectralis OCT (Heidelberg Engineering GmbH, Heidelberg, Germany) equipped with the Anterior Segment Module. Images from over 2500 separate study visits were obtained using standardized imaging parameters. The following stepwise approach was recommended to properly orient the volume scans over the extrascleral flange of the PDP ensuring that the scans are centered on the implant with adequate depth: (1) the volume scan was aligned such that: (i) the long axis of the scan was oriented parallel to the implant flange long axis, (ii) the imaging field was centered on the implant septum center, and (iii) it covered the entirety of the implant, with equal margins on either side of the implant flange; (2) the depth of the scan focus was adjusted to ensure that the conjunctiva and Tenon's capsule over the overmold, as well as sclera under the implant flange, and the septum of the implant, were captured; and (3) Steps 1 and 2 were then repeated after the scan orientation was changed so that the short-axis scans were oriented parallel to the implant flange short axis. Results: Utilization of AS-OCT during clinical development of the PDP allowed visualization of anterior segment features, including the conjunctiva, Tenon's capsule, and sclera, surrounding the PDP. Overall, these best practices enabled detailed structural imaging of the implant's interface with surrounding ocular tissues. Common errors resulting in poor AS-OCT image acquisition included off-center raster scans, scans not being aligned parallel to the long and/or short axes of the PDP implant, or not being oriented along the implant axes, and inappropriate scan depths. Conclusions: Application of a standardized AS-OCT imaging procedure was used to obtain high-quality, high-resolution images of anterior segment features in the presence of the PDP implant. The best practices reported are not a requirement for managing eyes with the PDP, but a recommendation for how to obtain high-quality images of the anterior segment of eyes with the PDP implant.