Long-term results of deep anterior lamellar versus penetrating keratoplasty.

OBJECTIVE: To compare deep anterior lamellar keratoplasty (DALK) with penetrating keratoplasty (PK) in eyes with corneal diseases not involving the corneal endothelium (keratoconus, scars after infectious keratitis, stromal dystrophies, and trauma). DESIGN: Retrospective, comparative case series. PARTICIPANTS: One hundred forty-two consecutive DALK (DALK group; big-bubble technique or manual lamellar dissection using a slitlamp) and 142 matched PK (PK group). METHODS: Three models were used to describe the postoperative outcomes of the endothelial cell density. A joint regression model was used to predict long-term graft survival. Visual acuity, ultrasound pachymetry, specular microscopy, and optical coherence tomography (OCT) findings were recorded. MAIN OUTCOME MEASURES: Postoperative endothelial cell loss and long-term predicted graft survival. RESULTS: The average 5-year postoperative endothelial cell loss was -22.3% in the DALK group and -50.1% in the PK group (P<0.0001). The early- and late-phase annual rates of endothelial cell loss were -8.3% and -3.9% per year, respectively, in the DALK group and -15.2% and -7.8% per year in the PK group (P<0.001; biphasic linear model). The median predicted graft survival was 49.0 years in the DALK group and 17.3 years in the PK group (P<0.0001). The average visual acuity was lower in the manual dissection subgroup compared with the PK group (average difference, 1.0 to 1.8 line) and with the big-bubble subgroup (average difference, 2.2 to 2.5 lines). The average central corneal thickness at 12 months was 536 µm in the PK group, 523 µm in the big-bubble subgroup, and 562 µm in the manual dissection subgroup (P<0.001). The average thickness of the residual recipient stroma measured by OCT was 87±26 µm in the manual dissection subgroup. No correlation was found between this figure and logarithm of the minimal angle of resolution at any postoperative time point (P>0.05). CONCLUSIONS: Long-term, model-predicted graft survival and endothelial densities are higher after DALK than after PK. The big-bubble technique gives better results than manual dissection and PK. Compared with PK, manual dissection provides higher survival of both the corneal endothelium and graft, but lower visual acuity.

Association of Radiation Dose to the Eyes With the Risk for Cataract After Nonretinoblastoma Solid Cancers in Childhood.

IMPORTANCE: Few studies have been published on the association of the radiation dose received to the eyes during radiotherapy (RT) for childhood cancer and the risk for later cataract. OBJECTIVE: To investigate the risk for cataract after treatment of nonretinoblastoma solid cancer in childhood. DESIGN, SETTING, AND PARTICIPANTS: The study used data from the Euro2K cohort that includes 4389 5-year survivors of solid tumors treated from January 1, 1945, to December 31, 1985; of these, 3172 patients were treated in France. A self-reported questionnaire was sent to French survivors from September 1, 2005, to December 31, 2012, when follow-up was considered completed for this study. However, 619 patients died before the beginning of the study and 128 patients treated for a retinoblastoma or who underwent enucleation were excluded. Likewise, 429 patients with unknown addresses or who did not return the consent form and 163 nonresponders did not participate. The remaining 1833 patients who completed the questionnaire underwent analysis for this study from June 1, 2014, to December 7, 2015. MAIN OUTCOMES AND MEASURES: Radiation doses in both eyes for individuals were estimated for all patients who had received RT. The role of the radiation dose in cataract risk was investigated using the Cox proportional hazard regression model and the excess relative or the absolute risk model. The role of ctytotoxic chemotherapy was also investigated. RESULTS: The 1833 patients (961 men [52.4%]; 872 women [47.6%]; mean [SD] age, 37.0 [8.5]) who returned the questionnaire were included in the analysis. After a mean follow-up of 32 years, 33 patients with unilateral or bilateral cataract were identified, for a total of 47 cataract events. The 47 events were validated by medical record review and by contacting the patients and the corresponding medical physician or ophthalmologist to obtain copies of diagnostic examinations or surgical reports. Overall, in a multivariable Cox proportional hazard regression analysis, patients who received RT had a 4.4-fold (95% CI, 1.5- to 13.0-fold) increased risk for cataract compared with patients who did not receive RT. Exposure to radiation doses of at least 10 Gy to the eyes increased the hazard ratio 39-fold (95% CI, 12.0- to 127.9-fold), relative to no radiation exposure. Although based on few patients, a strong increase in cataract risk (hazard ratio, 26.3; 95% CI, 7.1-96.6) was observed in patients treated with melphalan hydrochloride. CONCLUSIONS AND RELEVANCE: This study can inform guideline-based recommendations for long-term follow-up for cataract.

A reproducible automated segmentation algorithm for corneal epithelium cell images from in vivo laser scanning confocal microscopy.

PURPOSE: To evaluate an automated process to find borders of corneal basal epithelial cells in pictures obtained from in vivo laser scanning confocal microscopy (Heidelberg Retina Tomograph III with Rostock corneal module). METHODS: On a sample of 20 normal corneal epithelial pictures, images were segmented through an automated four-step segmentation algorithm. Steps of the algorithm included noise reduction through a fast Fourier transform (FFT) band-pass filter, image binarization with a mean value threshold, watershed segmentation algorithm on distance map to separate fused cells and Voronoi diagram segmentation algorithm (which gives a final mask of cell borders). Cells were then automatically counted using this border mask. On the original image either with contrast enhancement or noise reduction, cells were manually counted by a trained operator. RESULTS: The average cell density was 7722.5 cells/mm(2) as assessed by automated analysis and 7732.5 cells/mm(2) as assessed by manual analysis (p = 0.93). Correlation between automated and manual analysis was strong (r = 0.974 [0.934-0.990], p < 0.001). Bland-Altman method gives a mean difference in density of 10 cells/mm(2) and a limits of agreement ranging from -971 to +991 cells/mm(2) . Visually, the algorithm correctly found almost all borders. CONCLUSION: This automated segmentation algorithm is worth for assessing corneal epithelial basal cell density and morphometry. This procedure is fully reproducible, with no operator-induced variability.

Long-term rejection incidence and reversibility after penetrating and lamellar keratoplasty.

PURPOSE: To identify risk factors for corneal graft rejection and rejection irreversibility. DESIGN: Retrospective cohort study. METHODS: setting: Institutional. patients: A total of 1438 consecutive eyes of 1438 patients who underwent corneal transplantation for optical indication at the Centre Hospitalier National d'Ophtalmologie des XV-XX, Paris, France, between December 1992 and December 2010 were studied. Surgical technique was penetrating keratoplasty (PK) in 1209 cases, anterior lamellar keratoplasty (ALK) in 165 cases, and Descemet stripping with endothelial keratoplasty in 64 cases. main outcome measures: Cumulative incidence of rejection episodes and rejection irreversibility rate. RESULTS: A total of 299 cases of rejection episodes were identified, of which 145 (48.5%) were irreversible after treatment. In multivariate analysis, the cumulative incidence of rejection episodes was influenced by recipient age (P = .00002), recipient rejection risk (P = .0003), lens status (P = .00003), and surgical group (P = .035). A higher incidence of rejection episodes was observed in young patients (<20 years) and patients aged from 41 to 50, high-risk recipients, aphakic eyes and eyes with anterior chamber intraocular lens, and eyes with PK (compared with eyes with ALK). Rejection episodes were more likely to be irreversible for high-risk recipients (P = .02), for eyes with preoperative hypertony (P = .009), and for eyes with poor visual acuity at presentation (P = .002). CONCLUSIONS: Recipient rejection risk and surgical group are the main risk factors for rejection as they both influence the incidence of rejection and the reversibility rate. Recipient age and lens status are predictive factors for the occurrence of rejection. Preoperative hypertony is a predictive factor for rejection irreversibility.