Limbal relaxing incision (LRI) has been shown to effectively reduce astigmatism when performed with or without cataract surgery. Recent introduction of multifocal IOL requires accurate astigmatism management such as within 1D. Although LRI can be performed using relatively low cost instruments, its accuracy is not as high as excimer laser correction. In conventional LRI, it is difficult to identify steep meridian during operation due to coarse pre-op marking, tilting of patient’s head, and cyclotorsion. We developed new procedure to make LRI more accurate by utilizing corneal-conjunctiva pre-op marking and axis identification in topographic image.
The procedure is as following:
1. Placing an axis mark on the cornea and the conjunctiva using an axis marker AE-2748 (Fig1 A).
2. Identifying this mark in the corneal topographic image (TMS-4, Tomey). The marking on the conjunctiva is easily identified and the geologic relation between the mark and the steep meridian can be confirmed (Fig 1 B).
3. Performing LRI based on the axis mark. Fixation ring AE-1591 with an angled gauge is placed to meet the axis mark on the cornea, and incisions marking is made by placing an LRI incision marker, AE-2857 (8.0mm), AE-2858 (8.5mm), or AE-2859 (9.0mm) into the fixation ring (Fig 1C). LRI is performed on the steepest meridian using a double-footed diamond knife AE-8122A.
by Kazunori Miyata on 19 Aug 2014