Background To evaluate the safety and efficacy of corneal allogenic intrastromal ring segments in the management of keratoconus patients. Methods The retrospective, nonrandomized, interventional case series consisted of 65 keratoconic eyes of 49 consecutive patients who had ring segment-shaped corneal allografts (KeraNatural®) implanted in intrastromal tunnels created using a femtosecond laser. The main outcome measures were uncorrected visual acuity (UCVA), corrected distant visual acuity (CDVA), refraction, keratometry, and pachymetry. Computed tomography scans of the corneal surfaces were also performed preoperatively as well as 3, 6 and 12 months postoperatively. Results Mean age was 29.5 ± 7.3 years (median 29, range: 20–52 years). The mean UCVA improved from 0.91 ± 0.50 logMAR preoperatively to 0.40 ± 0.24 logMAR postoperatively at 6 month follow-up (p < 0.01) and the mean CDVA improved from 0.87 ± 0.20 logMAR preoperatively to 0.27 ± 0.06 logMAR postoperatively (p < 0.01). The mean spherical equivalent improved from −8.82 ± 4.57 to −3.45 ± 4.81D (p < 0.01). Average Keratometry decreased from 49.23 ± 5.22 preoperatively to 45.63 ± 4.89 D postoperatively (p < 0.01). Mean anterior and posterior maximum elevation were also decreased significantly (p < 0.01). In one patient, dislocation of the graft towards the tunnel incision site and dehiscense at the tunnel entrance were observed in the first week of the operation. Yellow-white deposits were observed in the segment tunnels in five cases after 6 months. Conclusion This study demonstrated that implantation of corneal allograft ring segments is a viable alternative treatment for keratoconus with safety and good visual results.
To compare predictability of the outcomes of Muller’s muscle conjunctiva resection (MMCR) in patients with severe versus mild/moderate involutional aponeurotic ptosis. This was a retrospective case-control study. All cases were recruited into the groups in terms of preoperative marginal reflex distance of upper eyelid (MRD-1). Group 1 consisted of patients with mild to moderate blepharoptosis was defined as an MRD-1 equal to 1.1 to 3 mm and Group 2 consisted of patients with severe blepharoptosis defined as MRD-1 ⩽ 1 mm. All patients underwent MMCR based on the response to phenylephrine and the amount of ptosis. MRD-1 obtained both manually and with ImageJ analysis program preoperatively and on the postoperative sixth month was compared. Successful surgical outcome criteria were defined as MRD-1 ⩾ 2.5 mm and inter-eyelid symmetry ⩽ 1 mm. A total of 97 eyes of 83 participants met the inclusion criteria for this study (Group 1 n = 50, Group 2 n = 47). In terms of MRD-1 success rates were 88% in Group 1, and 70.2% in Group 2 (p = 0.03). Preoperative MRD-1 which was measured by ImageJ, and the amount of resected tissue in mm were the predictive data of surgical outcome by the logistic regression analysis (OR 6.45, 95% CI 1.82–22.78, p = 0.004, OR 2.47, 95% CI 1.05–5.80, p = 0.037, respectively). The surgical success of MMCR can be predicted via tissue resection length and preoperative MRD-1. Higher surgical success rates were obtained in cases with mild-moderate ptosis and clinically acceptable success rates were obtained in cases with severe ptosis.
Objectives: To evaluate predictive factors for corneal scar formation following corneal collagen cross-linking (CXL). Methods: The medical records of 295 progressive keratoconus patients who had undergone accelerated CXL were reviewed retrospectively in this comparative cohort study. Thirty-two eyes of 32 patients who still had a corneal scar in the first year (scar group) and 75 eyes of 75 patients without any scar (control group) were included. The patients’ demographic characteristics, preoperative uncorrected distance visual acuity (UCVA) and corrected distance visual acuity (CDVA), slit-lamp biomicroscopy and corneal topographic parameters data were acquired from the patients’ files. Multivariable logistic regression analysis and Receiver operating characteristic (ROC) curves were used for the purpose of evaluating predictive factors for corneal scar formation. Results: The UCVA and CDVA, which were determined to be similar between the groups during the preoperative period (P = .63, P = .71, respectively), improved postoperatively in both groups (P = .98, p = .10, respectively). The thinnest point of corneal thickness was statistically lower in the scar group (p = .03). In multivariable logistic regression analysis, preoperative keratometric astigmatism was a predictive value showing postoperative scar development (OR 11.81 95% CI 2.46–56.62, p = .002). Keratometric astigmatism had the highest sensitivity (90%), specificity (86.7%), and accuracy (95%) for scar formation at the best cut-off point of 5.61 D according to the ROC curve. Conclusions: A higher tendency for stromal haze development following CXL was determined in eyes with thinner corneas and higher keratometric astigmatism with the best cut-off value of 5.61 D.
18 November 2017 in International Journal of Ophthalmology
To investigate the effect of pomegranate juice (PJ) intake on overall oxidation status in retinas of diabetic rats. Twenty-seven rats were divided into four groups as control (CO), diabetic (DM), control treated with PJ (CO-PJ), and diabetic treated with PJ (DM-PJ).The retina tissues were used to determine 8-hydroxy-2'-deoxyguanosine (8OHdG), malondialdehyde (MDA), reduced glutathione (GSH) levels, and the enzyme activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px). The levels of 8OHdG and MDA were significantly increased in the retina of DM group compared to CO group (P=0.001, P<0.001 respectively). Both 8OHdG and MDA levels were decreased in PJ-DM group compared to DM group (P=0.004, P<0.001 respectively). The activities of antioxidant enzymes GSH, SOD, and GDH-Px were significantly decreased in the retina of DM group compared to CO group (P≤0.01). GSH and GSH-Px activities were higher in PJ-DM group compared with DM group (P=0.010, P=0.042, respectively) but SOD activity was not statistically different (P=0.938). PJ intake is found to be effective in decreasing oxidative end products, and in increasing the activities of antioxidant enzymes in diabetic retinas of rats, which suggests it may be effective against oxidative stress in diabetic retinas.
31 March 2020 in Graefe's Archive for Clinical and Experimental Ophthalmology