Use of four asymmetric marks to orient the donor graft during Descemet's membrane endothelial keratoplasty

Abstract

IntroductionMaintaining the correct orientation of the donor graft is important during Descemet's membrane endothelial keratoplasty (DMEK). We describe a new method of marking the donor graft prior to DMEK.MethodsTwelve eyes of 10 patients with bullous keratopathy who underwent DMEK were retrospectively analysed. Donor discs were created by stripping the endothelium–Descemet's membrane layer from corneoscleral buttons. Four semicircular marks, two 1.0 mm and two 1.5 mm in diameter, were created at the edge of the donor disc. The small and large marks were paired. Each donor graft was inserted into the anterior chamber, unfolded and attached to the posterior corneal stroma with an air bubble.ResultsThe inserted grafts were all appropriately orientated when attached to the back surfaces of the corneas. The two pairs of asymmetric marks afforded valuable guidance. Even when the graft was partially folded or decentred, and one pair of marks was obscured, the other pair was always visible to indicate graft orientation. Best spectacle-corrected visual acuity improved significantly in all patients (p<0.001). Compared with the preoperative endothelial cell density of the donor graft, that of the corneal endothelium had decreased 44.0%±10.0% by 6 months after surgery.ConclusionsTwo pairs of asymmetrical semicircular marks placed on the edge of the donor graft allowed appropriate graft orientation during DMEK.

<p>Microscope Integrated Intraoperative Optical Coherence Tomography-Guided DMEK in Corneas with Poor Visualization</p>

“…The use of S mark or four asymmetrical marks have been described to identify correct orientation of the DM roll prior to air injection; however, in most of our cases, the exact orientation of S mark was difficult to identify due to corneal haze. 13,14,16 In some cases, although the S mark was apparent in the beginning of the surgery, it became difficult to identify it with passage of time. In all these cases, Mi-OCT helped us in identifying the orientation of the DM roll and correct localization of the endothelial side.…”

Body Mass Index Changes: An Assessment Of The Effects Of Age And Gender Using The E-Norms Method

“…The e-norms method [10] allows the use of data derived from a provider's own cohort to produce normative values for any parameter in their database. The method has been validated by various authors for neurophysiological and non-neurophysiological studies ranging from electrodiagnostic studies, [11] , [12] , [13] , [14] , [15] to acetyl choline receptor antibodies (AchRAb) for diagnosing myasthenia gravis (Guan Y, unpublished data), to intra-epidermal nerve ber density (Authier FJ, unpublished data), and more recently to Ophthalmology, for deriving biometric normative data used for intraocular lens (IOL) power calculation prior to cataract surgery (Shammas H, Jabre, J -In Press, BMJ Open Ophthalmology September 2020) [16]. To date, normative data derived using the e-norms method in all these studies was found to closely match data obtained from traditional studies, producing much needed normative data in populations and cohorts for which no normative values were available.…”

Outcomes of Descemet Membrane Endothelial Keratoplasty for Vitrectomized Eyes with Sutured Posterior Chamber Intraocular Lens

“…A punch was gently placed on the endothelial surface to indent a circle 7.75, 8.0, or 8.25 mm in diameter. Subsequently, 1.0 and 1.5 mm- diameter dermatological biopsy punches (Kai Industries, Seki, Japan) were used to place asymmetric marks on the edges of the identified circles [ 19 ]. Donor grafts thus marked were stained with 0.1% ( w/v ) BBG (1.0 mg/mL) for 1 min and stored in BSS prior to insertion, 30 min later [ 20 ].…”