BASIC INVESTIGATION Sutured Clear Corneal Incision: Wound Apposition and Permeability to Bacterial-Sized Particles William N. May, MD,* Juan Castro-Combs, MD,† Renata T. Kashiwabuchi, MD,† Woranart Tattiyakul, MD,† Saima Qureshi-Said, MD,† Flavio Hirai, MD, PhD,‡ and Ashley Behrens, MD† Purpose: To determine the effects of single radial or horizontal suture placement in 2-step clear corneal incision (CCI) wound apposition and permeability to particles of India ink. Methods: Five fresh human globes were included. Two 25-gauge needles connected to a saline solution bag and to a digital manometer were inserted through the limbus, 120 degrees apart from each other. Four 2-step CCIs (2.75 mm wide and 3 mm length) were constructed in each cornea. Incisions were divided into 3 groups: single radial suture (SRS), single horizontal suture (SHS), and unsutured group. Optical coherence tomography (OCT) was performed before and after suture placement. With a preset 10 mm Hg intraocular pressure (IOP), India ink was applied to the incision site and a standardized sudden IOP fluctuation was induced. OCT and superficial images were recorded before and after suture placement. India ink inflow and internal and external CCI gapping were outlined and measured by planimeter. Results: The area and linear distance of India ink inflow after pressure challenge in all study groups were higher when compared with pre-pressure measurements; however, this increase was signif- icant in the SRS and SHS groups (P , 0.05). Additionally, SRS placement significantly increased inner wound gapping (P = 0.018), and SHS significantly widened outer wound gape (P = 0.02). Conclusions: Well-constructed unsutured 2-step CCI seems to be more efficient at preventing bacterial-sized particles inflow during sudden changes in IOP, and it seems to offer better wound apposition as assessed by OCT. Key Words: cataract surgery, clear corneal incision (Cornea 2013;32:319–325) T he inflow of bacterial-sized particles of India ink through sutureless clear corneal incisions (CCI) in response to changes in intraocular pressure (IOP) during the early post- operative period has been described in controlled laboratory models. 1,2 Studies performed in patients who underwent cat- aract surgery in which sutureless CCIs were employed have reported the penetration of blood, trypan blue, and antibiotic ointment into the anterior chamber in the immediate postop- erative period. 3–5 CCI architecture and wound self-sealing capacity play an important role in the development of postoperative endo- phthalmitis (POE). 6–9 Failing to provide a completely sealed anterior chamber after surgical intervention could result in the development of a suction system during changes in IOP resulting in the inflow of extraocular fluid and particles into the anterior chamber. 10 This may suggest that suturing CCIs could reduce the risk of developing POE. Optical coherence tomography (OCT) is a valuable tool to assess corneal wound anatomy and wound architecture. 11 OCT has been shown to accurately detect epithelial gaping, endothelial gaping, endothelial misalignment, and Descemet detachments with more detail than other techniques used for the visualization of corneal features, such as slit-lamp micros- copy, confocal microscopy, and ultrasound biomicroscopy. Moreover, this imaging technique can measure corneal inci- sion dimensions and other anterior chamber structures with great precision. 9,12,13 The purpose of this study was to determine the effects of 2 different suture techniques (radial and horizontal) in India ink particle inflow prevention during sudden changes in IOP and wound apposition assessed by OCT in the 2-step CCI configuration. MATERIALS AND METHODS Experimental Setting Five fresh human donor globes unsuitable for corneal transplantation were obtained from Lions Eye Institute for Transplant and Research (Tampa, Florida) for the study. The globes were kept at 4°C in a moist chamber before use. Each eye was mounted on a rubber base and the remaining con- junctiva was secured in all 4 quadrants with pins. This base was fixed into a supporting styrofoam receptacle. A 25-gauge needle (BD Biosciences, Franklin Lakes, NJ) connected to a balanced saline solution (BSS) bag Received for publication November 21, 2011; revision received January 16, 2012; accepted January 23, 2012. From the *Doheny Eye Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA; †The Wilmer Eye Institute, The Johns Hopkins University School of Medicine, Baltimore, MD; and ‡Pau- lista School of Medicine, Federal University of Sao Paulo, Sao Paulo, Brazil. Supported by the May Vision Foundation, Los Angeles, California; an unrestricted grant from Research to Prevent Blindness, New York, New York, to Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland; and a Research to Prevent Blindness Althouse Special Scholars Award and Fight For Sight, New York, New York. The authors state that they have no proprietary interest in the products named in this article. Reprints: William N. May, 15141 Whittier Boulevard, Suite 480 Whittier, CA 90603 (e-mail: williamnmaymd@gmail.com). Copyright © 2012 by Lippincott Williams & Wilkins Cornea  Volume 32, Number 3, March 2013 www.corneajrnl.com | 319