Dataset Information

Graft-size selection and anisometropia reduction in penetrating keratoplasty (PKP).

ABSTRACT:

Purpose

To compare the amount of myopia induced by same-size donor-to-host penetrating keratoplasty with that of the amount of myopia induced by over-sized donor-to-host penetrating keratoplasty.

Setting

Tertiary referral academic center.

Design

Retrospective cohort study.

Methods

Charts from patients who underwent penetrating keratoplasty by the same technique at Bascom Palmer Eye Institute between Nov 1, 2002, and January 1, 2006, were reviewed. The patients underwent optical penetrating keratoplasty using 12 interrupted 10-0 nylon sutures and a 12-bite continuous 10-0 nylon suture by a single surgeon (R.K.F.). The surgical technique used would be considered standard of care at most institutions. The Institutional Review Board, University of Miami Human Subjects Research Office, approved the study protocol. The donor graft was over-sized by 0.25mm in eyes when the intended final refractive target was greater than -1.00 diopters spherical equivalent (SE). The same-size donor graft was used when the intended final refractive target was less than -1.00 diopters SE. The selection of donor graft size was entirely based upon clinical parameters, meaning that the intended final refractive target was determined per each patient's fellow eye refraction, with the intention of reducing anisometropia. All patients received postoperative refraction and corneal topography. These measurements were performed at 6-8 weeks when the initial removal of sutures commenced, then at 6 months, then after completion of selective suture removal, then again at 12 months.

Results

At 12 months, the over-sized group resulted in -1.35 diopters (SD = 2.25) SE of refraction, and the same-size group resulted in -0.14 diopters (SD = 2.42) SE. This approached statistical significance (p = 0.052) in comparison to -1.00 diopters spherical equivalent.

Conclusions

Using a donor graft that is over-sized by 0.25mm results in refraction of -1.00 diopters SE or more of myopia. Using a same-size donor-graft results in refraction of less than -1.00 diopters SE. Therefore, careful graft-size selection can result in a more favorable clinical outcome-namely, reduction in anisometropia-in patients undergoing penetrating keratoplasty.

SUBMITTER: Koo EH

PROVIDER: S-EPMC6586274 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Graft-size selection and anisometropia reduction in penetrating keratoplasty (PKP).

Koo Ellen H EH Feuer William J WJ Forster Richard K RK

PloS one 20190620 6

<h4>Purpose</h4>To compare the amount of myopia induced by same-size donor-to-host penetrating keratoplasty with that of the amount of myopia induced by over-sized donor-to-host penetrating keratoplasty.<h4>Setting</h4>Tertiary referral academic center.<h4>Design</h4>Retrospective cohort study.<h4>Methods</h4>Charts from patients who underwent penetrating keratoplasty by the same technique at Bascom Palmer Eye Institute between Nov 1, 2002, and January 1, 2006, were reviewed. The patients underw ...[more]

PMID: 31220145

Similar Datasets

Project description:ImportanceEndothelial morphometric measures have potential value in predicting graft failure after penetrating keratoplasty.ObjectiveTo determine whether preoperative and/or postoperative central morphometric measures (endothelial cell density [ECD], coefficient of variation [CV], and percentage of hexagonality [HEX]) and their postoperative changes are predictive of graft failure caused by endothelial decompensation after penetrating keratoplasty to treat a moderate-risk condition, principally Fuchs dystrophy or pseudophakic corneal edema.DesignIn a subset of Cornea Donor Study participants with graft failure, a central reading center determined preoperative and postoperative ECD, CV, and HEX from available central endothelial specular images.SettingCornea Image Analysis Reading Center of the Specular Microscopy Ancillary Study.ParticipantsEighteen patients with graft failure due to endothelial decompensation and 54 individuals matched for most donor and recipient measures at baseline whose grafts did not fail.Main outcome measureChange in ECD, CV, and HEX values.ResultsPreoperative ECD was not associated with graft failure (P = .43); however, a lower ECD at 6 months was predictive of subsequent failure (P = .004). Coefficient of variation at 6 months was not associated with graft failure in univariate (P = .91) or multivariate (P = .79) analyses. We found a suggestive trend of higher graft failure with lower HEX values at 6 months (P = .02) but not at the established statistical significance (P < .01). The most recent CV or HEX values, as time-dependent variables, were not associated with graft failure (P = .26 and P = .81, respectively). Endothelial cell density values decreased during follow-up, whereas CV and HEX appear to fluctuate without an apparent trend.Conclusions and relevanceEndothelial cell density at 6 months after penetrating keratoplasty is predictive of graft failure, whereas CV and HEX appear to fluctuate postoperatively, possibly indicating an unstable endothelial population in clear and failing grafts.Trial registrationclinicaltrials.gov Identifier: NCT00006411.

Project description:BackgroudPrevious studies of internal graft-host malappositions have not dealt with the precise ways in which each malapposition affected post-penetrating keratoplasty (post-PK) visual outcomes. In this study, we reviewed our post-PK and post-deep anterior lamellar keratoplasty (post-DALK) keratoconic patients and used anterior segment optical coherence tomography (AS-OCT) to evaluate the associations between graft-host interface (GHI) characteristics and visual outcomes.MethodsNovel GHI metrics included: mean graft-host touch (GHT), total prevalence of malapposition proportion (Pm), frequency of apposition (F), size of malapposition (Sm), junctional graft thickness (Tg), junctional host thickness (Th) and the absolute value of difference between Tg and Th (|Tg-Th|). We connected the external and internal junction points of GHI (GHT) and drew a straight line through the central point, perpendicular to both sides of the cornea. Tg and Th were the thicknesses at cross-points 1?mm away from the meeting point on the external side of the graft and host, respectively. Linear regression analysis was used to describe associations between GHI metrics and postsurgical visual outcomes [logarithm of minimum angle of resolution best-corrected visual acuity (logMAR BCVA), spherical equivalent diopter (SE), diopter of spherical power (DS), diopter of cylindrical power (DC) and keratometric astigmatism (Astig value)].ResultsWe enrolled 22 post-PK and 23 post-DALK keratoconic patients. Compared with the regular-apposition results, GHT was decreased in step and gape patterns, and increased in hill and tag patterns. SE increased averagely by 6.851, 5.428 and 5.164 diopter per 1% increase in: F (step) [??=?6.851; 95% Confidence interval (CI)?=?2.975-10.727; P?=?0.001]; F (graft step) [??=?5.428; 95% CI?=?1.685-9.171; P?=?0.005]; and Pm [??=?5.164; 95%CI?=?0.913-9.146; P?=?0.018], respectively. SE increased averagely by 0.31 diopter per 10-?m increment in |Tg-Th| [??=?0.031; 95% CI?=?0.009-0.054; P?=?0.007]. LogMAR BCVA increased (on average) by 0.01 per 10-?m increment in both GHT [??=?0.001; 95% CI?=?0-0.002; P?=?0.030]. and Tg [??=?0.001; 95% CI?=?0.001-0.002; P?=?0.001]. Astig value increased on average by 0.17 diopter per 10-?m increment in Sm [??=?0.017; 95% CI?=?0-0.033; P?=?0.047].ConclusionThis investigation of GHI characteristics suggests explanations for varied ametropia in keratoconic eyes and has potential significance as a reference for promoting pre-surgical planning and technology for corneal transplantation.

Dataset Information

Graft-size selection and anisometropia reduction in penetrating keratoplasty (PKP).

Purpose

Setting

Design

Methods

Results

Conclusions

Publications

Graft-size selection and anisometropia reduction in penetrating keratoplasty (PKP).

Similar Datasets

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