Basic InvestigationOptical Coherence Tomography of Descemet Membrane Separation by the Big Bubble TechniqueKaiserman, Igor MD, MSc, MHA; Bahar, Irit MD; Rootman, David S MD, FRCSCAuthor Information From the Department of Ophthalmology, Toronto Western Hospital, University of Toronto, Toronto, Ontario, Canada. Received for publication April 28, 2007; revision received June 6, 2007; accepted June 13, 2007. Supported by a fellowship from the American Physicians Fellowship for Medicine in Israel. The authors state that they have no proprietary interest in the products named in this article. Reprints: Igor Kaiserman, Department of Ophthalmology, Toronto Western Hospital, 399 Bathurst Street, Ontario, Canada M5T2S8 (e-mail: Igor@Dr-Kaiserman.com). Cornea: October 2007 - Volume 26 - Issue 9 - p 1115-1117 doi: 10.1097/ICO.0b013e318142bdb9 Buy Metrics Abstract Purpose: To image Descemet membrane separation by the big bubble technique in human corneas by using anterior segment optical coherence tomography (OCT). Methods: Five human corneoscleral rims were placed on an artificial anterior chamber and partially trephinated. A 23-gauge needle was inserted into the stroma under slit-lamp control and air was injected. The procedure was continuously imaged by anterior segment OCT. Results: In all corneoscleral rims, a big bubble was created. The spread of air seemed to follow the interlamellar spaces without crossing lamellae. It involved mainly the inner layers of the stroma while sparing the outer 212 ± 41 μm of the cornea (range, 168-271 μm). Intrastromal pressure build-up forced air above the Descemet membrane, creating tiny air bubbles of ∼355 ± 111 μm (range, 210-560 μm). When the pressure inside those bubbles reached a certain level, the bubbles spontaneously coalesced to form a big bubble. Conclusions: OCT is useful in imaging intracorneal air spread. The main obstacle to creating a big bubble is the impermeability to air of the imperforated posterior stromal lamellae. © 2007 Lippincott Williams & Wilkins, Inc.