Applications of three-dimensional printing in ophthalmology.

Three-dimensional (3D) printing is increasingly used to produce customized objects and is a promising alternative to traditional manufacturing methods in diverse fields, such as dentistry and orthopedics. Already in use in other medical specialties, adoption in ophthalmology has been limited to date. This review aims to provide an overview of 3D printing technology with respect to current and potential applications in ophthalmic practice. Medline, Embase, and Internet searches were performed with "3D printing," "ophthalmology," "dentistry," "orthopaedics" and their synonyms used as main search terms. In addition, search terms related to clinical applications such as "surgery" and "implant" were employed. 3D printing has multiple applications in ophthalmology, including in diagnosis, surgery, prosthetics, medications, and medical education. Within the past decade, researchers have produced 3D printed models of objects such as implants, prostheses, anatomical models and surgical simulators. Further development is necessary to generate optimal biomaterials for various applications, and the quality and long-term performance of 3D models needs to be validated.

Intrasession repeatability of optical coherence tomography measures in active neovascular age-related macular degeneration.

OBJECTIVES: To determine the repeatability of Stratus optical coherence tomography fast macular thickness map analysis in patients with active neovascular age-related macular degeneration (nAMD). METHODS: Consecutive pairs of scans from 112 eyes of 112 consecutive patients with active nAMD were analyzed. The Bland-Altman coefficient of repeatability (CR) was calculated for each retinal thickness or volume measure. RESULTS: The CR for the central 1 mm macular subfield was 59 µm (18% of retinal thickness) and did not exceed 69 µm in any subfield. There was much poorer repeatability for the center-point thickness (CPT) measure (CR of 78 µm; 24%). However, in the subgroup of 38 patients with no Stratus software low analysis confidence message on either analysis map, the revised CR (42 µm) for the CPT measure and the A1 subfield (40 µm) were similar. CONCLUSION: Optical coherence tomography-derived retinal thickness measurements are subject to measurement variability in patients with active nAMD. The results suggest a change criterion of more than 59 µm in central 1 mm (A1) subfield macular thickness is necessary to distinguish true clinical change from measurement variability in these patients.