CLINICAL SCIENCE Imaging Implanted Keratoprostheses With Anterior-Segment Optical Coherence Tomography and Ultrasound Biomicroscopy Julian P.S. Garcia, Jr., MD,*† Jose de la Cruz, MD,*‡ Richard B. Rosen, MD,*† and Douglas F. Buxton, MD*† Purpose: To describe the anterior ocular segment findings of eyes with implanted Boston type 1 keratoprostheses (KPro) in vivo by using anterior-segment optical coherence tomography (AS-OCT) and ultrasound biomicroscopy (UBM). Methods: A retrospective, comparative study was made of patients with implanted KPros who were examined with AS-OCT (AC Cornea OCT) and UBM (OTI Scan 35-50MHz Ultrasound). Results: One pseudophakic and 1 aphakic eye were included in the study. Cross-sectional AS-OCT adequately imaged the components of the KPro (front plate with stem, back plate, and titanium ring), the corneal graft, and host cornea. The angles could be seen as open, filled with debris, or closed. Coronal AS-OCT showed en face views of each KPro part. Retrokeratoprosthetic membranes were depicted to be thick opacities covering the rear optical surface of the stem. UBM, on the other hand, imaged the KPro front plate as a muffin-shaped space at the apical center, with the corneal graft appearing wispy and the host cornea grainy. The back plate, titanium ring, and angles could not be resolved. Glaucoma tubes and posterior-chamber intraocular lens (PCIOL) haptics were imaged below the iris plane. Conclusions: Cross-sectional AS-OCT adequately imaged the components of the assembled KPro in vivo, as well as its interaction with surrounding anterior-segment structures. It allowed visualization of the anterior chamber, iris, and angle, essential in the postoperative care of these patients. Coronal AS-OCT showed graphic en face images of the KPro device and suspected retrokeratoprosthetic mem- branes. UBM, on the other hand, adequately imaged glaucoma tube shunts and PCIOL haptics beneath the iris plane. Key Words: anterior-segment optical coherence tomography, coronal optical coherence tomography, optical coherence tomography, keratoprosthesis, ultrasound biomicroscopy (Cornea 2008;27:180–188) T he Boston type 1 keratoprosthesis (KPro) is a well-known and widely used corneal prosthesis in the United States today. Dubbed as the ‘‘artificial cornea,’’ this device is espe- cially indicated for eyes that have undergone repeated failed corneal transplantations. The KPro is composed of 2 poly- methyl methacrylate parts: a front plate with a threaded stem carrying the optical properties of the device and a back plate with a threaded central opening to accommodate the front plate stem and corneal graft (donor tissue). 1 The device looks like a mini ‘‘hubcap’’ when assembled,with the front plate on top and the back plate below, sandwiching the corneal graft. In addition, a titanium ring is locked in place under the back plate for added security. The corneal graft serves as a scaffold where the assembled KPro is sutured to the host cornea. If the natural lens is removed as generally recommended, a KPro model with aphakic correction is used. If the eye is left pseudophakic, a plano KPro model is put in place where the anterior-surface power is ;43–44 D. A bandage contact lens is worn indefinitely after surgery to decrease evaporative forces and protect the corneal surface from desiccation. 2 Because inflammation can beset eyes that have un- dergone repeated surgical procedures, patients with implanted keratoprostheses are frequently examined and monitored for possible complications such as scarring, continued deterio- ration of anterior-segment structures, and development of retrokeratoprosthetic membranes. 3–5 To date, there is no stan- dard means of observing the anterior segment and angle anatomy of eyes with implanted keratoprosthesis other than through slit-lamp examinations. Two state-of-the-art diagnostic techniques come to mind for imaging and documenting devices implanted on the cornea. One is the relatively new noncontact method of anterior-segment optical coherence tomography (AS-OCT), which makes use of 1300-nm infrared light. 6,7 The other is the water-immersion technique of ultrasound biomicroscopy (UBM), which uses 35–50 MHz of high-frequency ultra- sound waves. 8–10 Imaging with AS-OCT is technically more challenging because poor vision makes it difficult for the eye to Received for publication June 8, 2007; revision received August 27, 2007; accepted August 29, 2007. From the *New York Eyeand Ear Infirmary, New York, NY; the †New York Medical College, Valhalla, NY; and the ‡Illinois Eye and Ear Infirmary, Chicago, IL. Presented at the 2007 ARVO Meeting, May 5–9, 2007, Fort Lauderdale, FL. Disclosure: Richard B. Rosen has received travel reimbursement from OTI. Reprints: Julian P.S. Garcia, Jr., The New York Eye & Ear Infirmary Retina Center, 310 East 14th Street, New York, NY 10003 (e-mail: jgarcia@nyee. edu). Copyright Ó 2008 by Lippincott Williams & Wilkins 180 Cornea  Volume 27, Number 2, February 2008 Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.