Management of pediatric keratoconus - evolving role of corneal collagen cross-linking: an update.

Pediatric keratoconus demonstrates several distinctive management issues in comparison with adult keratoconus with respect to under-diagnosis, poor compliance and modifications in treatment patterns. The major concerns comprise of the accelerated progression of the disease in the pediatric age group and management of co-morbidities such as vernal keratoconjuntivitis. Visual impairment in pediatric patients may affect social and educational development and overall negatively impact their quality of life. The treatment algorithm between adults and pediatric keratoconus has been similar; comprising mainly of visual rehabilitation with spectacles, contacts lenses (soft or rigid) and keratoplasty (lamellar or penetrating) depending on the stage of the disease. There is a paradigm shift in the management of keratoconus, a new treatment modality, corneal collagen crosslinking (CXL), has been utilized in adult keratoconic patients halting the progression of the disease. CXL has been utilized for over a 10 year period and based on the evidence of efficacy and safety in the adult population; this treatment has been recently utilized in management of pediatric keratoconus. This article will present an update about current management of pediatric keratoconus with special focus on CXL in this age group

Retrephination of eccentric donor graft for descemet stripping automated endothelial keratoplasty.

We describe a technique of intraoperative eccentric retrephination of Descemet stripping automated endothelial keratoplasty (DSAEK) donor graft to avoid the presence of epithelium on the graft lenticule. Trephination of the DSAEK graft may prove to be very challenging for surgeons, especially when flap diameter is small; this can result in an eccentric trephination and the presence of epithelium on the graft. Insertion of epithelium with DSAEK donor graft into the anterior chamber could result in epithelial ingrowth and downgrowth, complications that may lead to poor visual outcomes, graft detachment, and anterior chamber angle closure. A second eccentric retrephination is a simple and easy-to-perform intraoperative surgical step that could avoid the presence of corneal epithelium on the DSAEK donor graft

Retrephination of eccentric donor graft for descemet stripping automated endothelial keratoplasty

We describe a technique of intraoperative eccentric retrephination of Descemet stripping automated endothelial keratoplasty (DSAEK) donor graft to avoid the presence of epithelium on the graft lenticule. Trephination of the DSAEK graft may prove to be very challenging for surgeons, especially when flap diameter is small; this can result in an eccentric trephination and the presence of epithelium on the graft. Insertion of epithelium with DSAEK donor graft into the anterior chamber could result in epithelial ingrowth and downgrowth, complications that may lead to poor visual outcomes, graft detachment, and anterior chamber angle closure. A second eccentric retrephination is a simple and easy-to-perform intraoperative surgical step that could avoid the presence of corneal epithelium on the DSAEK donor graft. Copyright © 2011 by Lippincott Williams & Wilkins

Alterations in endothelial cell density after photorefractive keratectomy with adjuvant mitomycin.

To elucidate the distinct role of the intraoperative use of mitomycin C (MMC) on endothelial cell density after photorefractive keratectomy (PRK) in human eyes. Prospective, double-masked, randomized clinical trial. One eye of 15 patients was treated with PRK with intraoperative use of topical 0.02% MMC (15 seconds), whereas the fellow eye was treated with Epipolis laser in situ keratomileusis (Epi-LASIK) in random order. Corneal confocal microscopy was performed in all eyes preoperatively and at one, three, six, and 12 months after the surgery. Moreover, three endothelial images were acquired in each of 15 preoperative-normal eyes to evaluate the repeatability of measuring endothelial cell density. Repeated measures analysis of variance was used to compare the temporal variations of endothelial cell density between the two techniques and the changes of endothelial cell density over time. The coefficient of repeatability of endothelial cell count was 148 cells/mm(2). Preoperative endothelial cell density was not significantly different between the two groups (P = .82). Moreover, the effect of the treatment on the temporal variation of endothelial cell density was insignificant (P = .83), whereas the differences between the preoperative and the postoperative endothelial cell densities reached statistical significance (P <or= .05). Nonetheless, inclusion of the repeatability of the instrument on the analysis diminished these significant differences (P > .05). The prophylactic intraoperative application of MMC (up to 15 seconds) after PRK does not seem to affect the endothelial cell density

Treatment of chronic dry eye: focus on cyclosporine.

To review the current treatment of chronic dry eye syndrome, focusing on cyclosporine A (CsA), a systematic literature search was performed using PubMed databases in two steps. The first step was oriented to articles published for dry eye. The second step was focused on the use of CsA in dry eye. A manual literature search was also undertaken based on citations in the published articles. The knowledge on the pathogenesis of dry eye syndrome has changed dramatically during the last few years. Inflammation and the interruption of the inflammatory cascade seem to be the main focus of the ophthalmologic community in the treatment of dry eye, giving the anti-inflammatory therapy a new critical role. The infiltration of T-cells in the conjuctiva tissue and the presence of cytokines and proteasis in the tear fluid were the main reason introducing the use of immunomodulator agents such as corticosteroids, cyclosporine, and doxycicline in order to treat dry eye syndrome. CsA emulsion is approved by the FDA for the treatment of dry eye, while clinical trials of this agent have demonstrated efficacy and safety of CsA. CsA seems to be a promising treatment against dry eye disease. New agents focused on the inflammatory pathogenesis of this syndrome in combination with CsA may be the future in the quest of treating dry eye. More studies are needed to determine the efficacy, safety, timing, and relative cost/effect of CsA

Intraocular lens power overestimation in a patient with history of circling keratorraphy.

We report a case of cataract extraction and intraocular lens (IOL) power overestimation in a patient with history of hyperopia managed with circling keratorraphy. A 65-year-old female presented to our institute complaining of decreased vision in both eyes. The patient had a history of bilateral hyperopia that was managed 20 years ago (1994) with circling keratorraphy. At presentation her uncorrected distance visual acuity (UDVA) was 20/70 and 20/60 in her right eye (OD) and left eye (OS), respectively, while her corrected distance visual acuity (CDVA) was 20/25 OD and 20/25 OS with manifest refraction of -0.50 + 1.50 × 75 OD and +0.50sph + 1.50cyl × 30 OS. Slit lamp examination revealed the presence of a circular intrastromal corneal suture (6 mm diameter) and mild (+1) nuclear sclerosis in both eyes. The patient was scheduled to undergo cataract extraction targeting plano, using a toric IOL; one month after the surgery, the manifest refraction of the operated right eye was -2.00 + 0.50 × 175, reflecting an overestimation of the intraocular lens (IOL) power for the attempted target. Cataract extraction in patients with history of circling keratorraphy for the management of hyperopia results in IOL power overestimation, consistent with that which is seen in patients with other previous hyperopic corneal refractive procedures

Dry eye after photorefractive keratectomy with adjuvant mitomycin C.

To report a patient with dry eye after bilateral photorefractive keratectomy (PRK) with mitomycin C treatment in one eye. A 29-year-old woman underwent PRK for moderate myopia. The left eye was randomly assigned and intraoperative topical mitomycin C was administered. The right (control) eye was treated with intraoperative corticosteroid only. The patient developed dry eye symptoms and superficial punctuate keratopathy in the eye treated with mitomycin C. Fifteen months after surgery no improvement was noted. Photorefractive keratectomy with mitomycin C treatment could induce or exacerbate dry eye