Changing indications and surgical techniques for corneal transplantation between 2004 and 2009 at a tertiary referral center

The aim of this study is to report the indications, techniques, and clinical outcomes of corneal transplantation and investigate any changing trends in surgical techniques over a 6 year period. Records of patients who had undergone any kind of corneal transplantation at Labbafinejad Medical Center, Tehran, Iran, from January 2004 to December 2009 were reviewed to determine the indications and types of corneal transplantation. Postoperative best-corrected visual acuity, refractive error, graft clarity, and complications were reported. During this period, 1859 eyes of 1624 patients with a mean age of 41.3 +/- 21.3 years underwent corneal transplantation. The most common indication was keratoconus [38.4%] followed by aphakic/pseudophakic bullous keratopathy [11.7%], previous failed grafts [10.6%], infectious corneal ulcers [10.1%], non-herpetic corneal scars [7.6%], trachoma keratopathy [4.7%], stromal corneal dystrophies [4.6%], post-herpetic corneal scar [3.7%], Fuchs' endothelial dystrophy [0.8%], and congenital hereditary endothelial dystrophy [0.4%]. Techniques of corneal transplantation included penetrating keratoplasty [PKP; 70.9%], deep anterior lamellar keratoplasty [DALK; 20.1%], conventional lamellar keratoplasty [LKP; 4.4%], and Descemet's stripping automated endothelial keratoplasty [DSAEK; 2.3%]. Over the study period, there was a significant increase in the relative frequency of infectious corneal ulcers, failed grafts, and trachoma keratopathy. Additionally, a significant reduction was observed in PKP and LKP procedures, and volume of DALK and DSAEK increased significantly. At final follow-up, 69.0% of grafts were clear in the PKP group. This figure was 82.6%, 82.7%, and 97.6% in the DALK, LKP, and DSAEK groups, respectively. Keratoconus was the most common indication and PKP was the most prevalent technique used for corneal transplantation. However, significant changes in the indications and surgical techniques were observed from 2004 to 2009

Higher-order aberrations in myopic eyes

To evaluate the correlation between refractive error and higher-order aberrations [HOAs] in patients with myopic astigmatism. HOAs were measured using the Zywave II aberrometer over a 6 mm pupil. Correlations between HOAs and myopia, astigmatism, and age were analyzed. One hundred and twenty-six eyes of 63 subjects with mean age of 26.4 +/- 5.9 years were studied. Mean spherical equivalent refractive error and refractive astigmatism were -4.94 +/- 1.63 D and 0.96 +/- 1.06 D, respectively. The most common higher-order aberration was primary horizontal trefoil with mean value of 0.069 +/- 0.152 micro m followed by spherical aberration [-0.064 +/- 0.130 micro m] and primary vertical coma [-0.038 +/- 0.148 micro m]. As the order of aberration increased from third to fifth, its contribution to total HOA decreased: 53.9% for third order, 31.9% for fourth order, and 14.2% for fifth order aberrations. Significant correlations were observed between spherical equivalent refractive error and primary horizontal coma [R=0.231, P=0.022], and root mean square [RMS] of spherical aberration [R=0.213, P=0.031]; between astigmatism and RMS of total HOA [R=0.251, P-0.032], RMS of fourth order aberration [R=0.35, P<0.001], and primary horizontal coma [R=0.314, P=0.004]. Spherical aberration [R=0.214, P=0.034] and secondary vertical coma [R=0.203, P=0.031] significantly increased with age. Primary horizontal trefoil, spherical aberration and primary vertical coma are the predominant higher-order aberrations in eyes with myopic astigmatism

Deep anterior lamellar keratoplasty: indications, surgical techniques and complications

The concept of lamellar keratoplasty [LK] is not new. However, it had been abandoned and largely replaced by the time-honored technique of penetrating keratoplasty [PK] because LK is technically demanding, time consuming and gives suboptimal visual outcomes due to interface irregularity arising from manual lamellar dissection. Recent improvements in surgical instruments and introduction of new techniques of maximum depth of corneal dissection as well as inherent advantages such as preservation of globe integrity and elimination of endothelial graft rejection have resulted in a re-introduction of LK as an acceptable alternative to con ventional PK. This review article describes the indications, different techniques, clinical outcomes and complications of deep anterior LK

Lensectomy and PCIOL implantation with versus without posterior capsulotomy and anterior vitrectomy for pediatric cataracts

To compare the visual outcomes and complications of lensectomy and posterior chamber intraocular lens [PCIOL] implantation with or without posterior capsulotomy and anterior vitrectomy in older subjects with pediatric cataracts. Seventeen eyes of 12 children aged 10 to 15 years with congenital or developmental cataracts were randomly divided to two groups. Lensectomy and PCIOL [Alcon Acrysof MA60 AC] implantation was performed with [8 eyes] or without [9 eyes] posterior capsulotomy and anterior vitrectomy. Mean age at the time of surgery was 12.3 +/- 1.5 [range 10-15] years and mean follow-up period was 18.7 +/- 11.2 [range 6-36] months. Posterior capsule opacification developed in three eyes in the non-vitrectomy group; however, media opacification was mild and capsulotomy was not required in any case. All eyes in the vitrectomy group had a clear visual axis at final follow-up [P=0.2]. No significant difference was observed between the two groups in term of visual acuity [P = 0.3] or complications. Although posterior capsulotomy and anterior vitrectomy seems to be safe in pediatric cataract surgery, it may not be necessary as a routine procedure in older children