Refractive outcomes of penetrating keratoplasty and deep anterior lamellar keratoplasty in fellow eyes for keratoconus.

PURPOSE: To compare the refractive outcomes following penetrating keratoplasty and deep anterior lamellar keratoplasty in fellow eyes in patients with keratoconus. METHODS: This is an observational retrospective review of consecutive patients with keratoconus first managed with penetrating keratoplasty in one eye and then with lamellar keratoplasty in the fellow eye, between 2002 and 2007. Data collection was based on patients' hospital records. Information related to assessment before surgery and at 1, 3, 6, 12, 24, and 48 months after keratoplasty were retrieved and considered in the analysis. Clinical evaluations included patients' medical histories and diagnosis of keratoconus, uncorrected and best corrected visual acuity, spherical equivalent, refractive cylinder, topographic cylinder, and high-order aberrations, complications, and adverse reactions. Data on contrast sensitivity, central corneal thickness, and central residual bed thickness (only for lamellar keratoplasty) were retrieved from anterior segment optical coherence tomography observation performed at 48 months. RESULTS: Sixteen patients (32 eyes), 7 males and 9 females, were included in the analyses. After 4 years from transplantation, at the end of follow-up, no statistically significant differences were found in visual acuity and refractive measures between the two keratoplasties. Perforating keratoplasty showed significant differences for contrast sensitivity at 6 cpd with maximum glare (p = 0.026) and without glare (p = 0.015). Deep anterior lamellar keratoplasty showed a negative correlation between central residual bed thickness and best corrected visual acuity (R = -0.414, p < 0.001). CONCLUSIONS: The manual pre-descemetic deep anterior lamellar keratoplasty used in this study showed refractive and visual results comparable to those obtained with penetrating keratoplasty. Such results indicated that leaving healthy stroma attached to Descemet's membrane does not compromise the clinical outcome in the short and long term after surgery.

In Vivo Confocal Microscopy 1 Year after Autologous Cultured Limbal Stem Cell Grafts.

PURPOSE: To correlate clinical, impression cytologic, and in vivo confocal microscopy findings on the corneal surface after cultured limbal stem cell transplantation. DESIGN: Prospective, interventional, noncomparative, masked case series. PARTICIPANTS: Thirteen patients with limbal stem cell deficiency after unilateral (9 eyes) or bilateral (2 eyes) chemical burn, liquid nitrogen injury (1 eye), or herpes simplex virus infection (1 eye). METHODS: Limbal cells were harvested from healthy or less affected eyes, cultured on 3T3 cells and fibrin glue, and transplanted to the patient's injured eye. Patients underwent clinical examination and impression cytologic examination of the central cornea before and 1 year after intervention. In vivo confocal microscopy scans were obtained in all corneal quadrants after 1 year. The interexamination agreement was established by calculation of the Cohen's κ coefficient. MAIN OUTCOME MEASURES: Results of surgery were assessed considering clinical signs (successful: restoration of transparent, avascular, and stable corneal epithelium without neovascularization in central corneal surface; partially successful: recurrence of superficial neovascularization; failed: recurrent epithelial defects, pannus, and inflammation), phenotype of cells covering the corneal surface (conjunctivalized corneal surface: cytokeratin 12 [cK12]-negative and mucin 1 [MUC1]-positive cells; mixed epithelium: cK12-positive and MUC1-positive cells; corneal epithelium: cK12-positive and MUC1-negative cells), and cell morphologic features (corneal epithelium: multilayered polygonal and flat cells with hyperreflective nuclei; conjunctival epithelium: stratified cuboidal or polygonal cells, hyperreflective cytoplasm, and barely defined borders; epithelial transition: transition of epithelial cells from the cornea to the conjunctiva over the corneal surface). RESULTS: We found a moderate to substantial degree of concordance between confocal microscopy and clinical evaluation (κ = 0.768) and between confocal microscopy and impression cytologic analysis (κ = 0.629). Confocal microscopy showed that 46.2% of patients exhibited corneal epithelium in the central and peripheral cornea, 30.8% showed an irregular mixed corneal and conjunctival epithelium, and 23.0% showed conjunctival epithelium. Palisades of Vogt were absent in all (100.0%) patients, and the cornea-conjunctiva epithelial transition localized approximately 1 mm internally on the cornea. CONCLUSIONS: Confocal microscopy provides objective measures of the corneal epithelium and may significantly improve the evaluation of outcomes after cultured limbal stem cell graft.