Comparison of densitometric profile after deep lamellar keratoplasty with two different techniques for treatment of keratoconus.

PURPOSE: To compare densitometric outcome of two techniques of deep lamellar keratoplasty using Pentacam HR corneal densitometry software. METHODS: Postoperative outcomes of 31 patients with big bubble (BB) and 28 patients with Melles (M) surgery for the treatment of keratoconus were evaluated. Data were gathered at least 3 months after the removal of all sutures including demographic data, uncorrected distance visual acuity (UCDVA), best spectacle-corrected visual acuity (BSCVA), refraction and endothelial cell count. Moreover, the Scheimpflug images were taken by Pentacam® HR to assess keratometric profile, densitometric outcomes in different depths and zones of the cornea and central corneal thickness. Anterior segment OCT was performed in ten cases of M group. RESULTS: Thirty-one eyes with BB and 27 eyes M surgery were enrolled. Comparison of densitometric profile between groups revealed no statistical significance in zone 0-2 mm, zone 2-6 mm and zone 10-12 mm in all depths (all P values > 0.05). Zone 6-10 mm of M group had lower densitometric readings (more transparent) in anterior, central and posterior layers of the cornea in comparison with BB group (all P < 0.05). Also no statistical difference was found in UCDVA, BSCVA, spherical or cylindrical refractive error, and spherical equivalent, keratometric readings, endothelial cell count and central corneal thickness in two groups (all P values > 0.05). CONCLUSION: Densitometric profiles were identical in both methods in visually important zones so as visual and refractive outcomes.

Clinical Practice Guidelines for Prevention, Diagnosis and Management of Early and Delayed-onset Ocular Injuries Due to Mustard Gas Exposure.

PURPOSE: To develop clinical practice guidelines (CPGs) for prevention, diagnosis, treatment and follow-up of ocular injuries caused by exposure to mustard gas. METHODS: The clinical questions were designed by the guideline team. Websites and databases including National Guidelines Clearinghouse, National Institute for Clinical Excellence, Cochrane, and PubMed were searched to find related CPGs and explore possible answers to the clinical questions. Since there were no relevant CPGs in the literature, related articles in Persian and English languages were extracted. Each article along with its level of evidence was summarized. Additionally, hand search was performed by looking the reference list of each article. Consequently, recommendations were developed considering the clinical benefits and side effects of each therapeutic modality. The recommendations were re-evaluated in terms of customization criteria. All recommendations along with the related evidence were scored from 1 to 9 by experts from all medical universities of Iran. The level of agreement among the experts was evaluated by analyzing the given scores. RESULTS: The agreement was achieved for all recommendations. The experts suggested a number of minor modifications which were applied to the recommendations. Finally, CPGs were developed with 98 recommendations under three major domains including prevention of injury, diagnosis and management of the acute and delayed-onset mustard gas ocular injuries. CONCLUSION: Considering the lack of CPGs for the prevention, diagnosis, and management of mustard gas-induced keratitis, these recommendations would be useful to prevent the serious ocular complications of mustard gas and standardize eye care services to the affected individuals.

Evaluation of the outcomes of corneal collagen cross-linking in progressive keratoconic eyes.

BACKGROUND: Corneal collagen cross-linking (CXL) is gaining popularity as a treatment in arresting the progression of keratoconus. It is a relatively new therapy using ultraviolet-A (UVA) with a photosensitizer to increase corneal stiffness. The purpose of this study was to evaluate visual, keratometric and topographic outcomes after corneal CXL in progressive keratoconic eyes. MATERIALS AND METHODS: In this prospective nonrandomized clinical study, 140 eyes of 110 patients with progressive keratoconus were treated by combined riboflavin/UVA CXL. Mean sphere, mean cylinder uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), manifest refractive spherical equivalent, corneal topography, pachymetry, and endothelial cell morphology were examined preoperatively and 12-24 months postoperatively. RESULTS: The preoperative mean sphere was -3.33 ± 3.13 diopter (D) and decreased to -3.09 ± 3.09 D (P = 0.007). The preoperative mean cylinder was -4.05 ± 2.29 D and changed to -3.79 ± 2.23 D (P = 0.011). UDVA changed from 0.95 ± 0.64 logarithm of the minimum angle of resolution (logMAR) to 0.85 ± 0.59 logMAR (P = 0.003). Thirty-five eyes (25%) gained one or more lines of preoperative UDVA, 87 eyes (62.1%) did not change and 18 eyes (12.8%) lost one or more lines of the preoperative UDVA. CDVA in 80% of the patients remained stable (no lines lost). Statistical analysis of keratometry, pachymetry, and endothelial cell count did not show the significant difference after surgery. CONCLUSION: Our study showed improvement in visual and refractive results of the corneal CXL and confirmed that CXL is the safe and effective procedure.