OCT-documented incision features and natural history of clear corneal incisions used for bimanual microincision cataract surgery.

The use of power modulation and the development of a new generation of intraocular lenses (IOL) have allowed phacoemulsification surgical techniques to move toward ever smaller incisions.1–3 It is now possible to perform phacoemulsification and implant IOLs through incisions less than 2 mm, which is commonly referred to as microincision cataract surgery (MICS).3 There are 2 types of MICS phacoemulsification: bimanual and coaxial. The bimanual MICS technique separates the irrigation and aspiration functions, each to a separate instrument. There is no irrigating sleeve on the phacoemulsification tip, which is known as sleeveless phacoemulsification. The efficacy of sleeveless phacoemulsification is established. When bimanual MICS was performed using an IOL that can be inserted through a sub-2 mm incision, visual acuities, corrected and uncorrected, were excellent, and retinal image quality was equal to that of conventional IOLs.3,4 Furthermore, bimanual MICS using sub-2 mm incision IOLs did not induce corneal astigmatism or corneal optical aberrations.5 Thus, bimanual MICS produced excellent outcomes. Still, bimanual sleeveless MICS is criticized for its steep learning curve, anterior chamber instability, limited infusion because of small instruments, and mechanical wound trauma.6 In part, to overcome these supposed problems, coaxial phacoemulsification through a sub-2 mm incision was introduced, coaxial MICS.7 When directly compared, coaxial and bimanual MICS, each had excellent visual results and similar surgically induced astigmatism and corneal endothelial cell loss.8,9 One ex vivo study, using scanning electron microscopy to describe the internal configuration of bimanual MICS incisions, suggested that the bimanual MICS incisions have less integrity than the coaxial MICS incisions; however, more recent clinical studies suggest otherwise.8–10 Anterior segment optical coherence tomography (OCT) can be used to describe the incision architecture of clear corneal incisions (CCI).11,12 To help understand the clinical healing of bimanual MICS incisions, the purpose of our study is to use OCT to describe changes of incision architecture over time after bimanual sleeveless MICS.