The evaluation of the risk factors for capsular complications in phacoemulsification.

PURPOSE: To determine and quantify the risk factors for disruption of lens capsule integrity during phacoemulsification. METHODS: The medical records of the patients who had undergone phacoemulsification cataract surgery and had a complication associated with lens capsule were reviewed. Consecutive cases were also reviewed in reverse chronological order as a control group. The exclusion criteria were pediatric cataracts, traumatic cataracts and lens dislocation. As a result, 403 uncomplicated and 83 complicated eyes were analyzed. The differences between the complication group and the group without complications regarding the risk factors were shown by employing the Chi-square test and Fischer's exact test. The variables having the level of significance (p < 0.25) after the Chi-square test and Fischer's exact test were enrolled into the multiple stepwise logistic regression analysis. RESULTS: Age (60-69/≤80) (p = 0.017), male gender (p = 0.006), pupil size ≤3 mm (p = <0.001), mature-brunescent cataract (p = <0.001), anterior chamber depth <2.5 mm (p = 0.001), posterior polar cataract (p = 0.006), diabetic retinopathy(p = <0.001), coronary artery disease (p = 0.098) and surgeon factor (junior resident/senior resident, p = 0.015; senior resident/specialist in ophthalmology, p = 0.026; junior resident/specialist in ophthalmology, p = 0.020) were among the factors significantly related to a capsule complication. An Excel program has been developed according to these results to predict the probability of capsule complication. CONCLUSIONS: Higher-risk cases can be predicted preoperatively, thus allowing surgeons to take appropriate precautions, better informing the patient and better selecting the cases especially for trainee surgeons.

Efficacy of single-dose dexamethasone implantation in patients with persistent diabetic macular edema.

To investigate the efficacy of single-dose intravitreal dexamethasone implantation in the treatment of persistent diabetic macular edema (DME) unresponsive to 3 consecutive ranibizumab injections over a period of 6 months. Forty-one patients with a previous history of treatment for DME including at least three consecutive intravitreal ranibizumab injections were enrolled in this retrospective study. Main outcome measures were change in best-corrected visual acuity (BCVA), central macular thickness (CMT), and intraocular pressure from baseline to 6th month. At the baseline, the mean CMT was 572.4 ± 123.1 µm which improved to 264.2 ± 114.4, 317.7 ± 141.7, 410.6 ± 169.1, and 382.8 ± 181.5 µm at the 1st, 3rd, 5th, and 6th month, respectively (p < 0.05). The preoperative mean BCVA was 0.85 ± 0.54 logMAR units which improved to 0.76 ± 0.5 (p = 0.08), 0.69 ± 0.4 (p = 0.02), 0.74 ± 0.4 (p = 0.284), and 0.72 ± 0.3 (p = 0.489) logMAR units at the 1st, 3rd, 5th, and 6th months, respectively. Additional injections were required for 13 (31 %) eyes at 3rd month and 14 (34 %) eyes at 5th month due to recurrence of macular edema. Intravitreal dexamethasone implantation caused a significant improvement of BCVA and reduction of CMT in the patients with persistent DME that were unresponsive to 3 consecutive ranibizumab injections. However, retreatment before 6 months in the majority of the patients was needed despite the beneficial effects after the index procedure.

Corneal Biomechanical Properties in Rheumatoid Arthritis.

PURPOSE: To investigate the variations in biomechanical properties of the cornea in rheumatoid arthritis (RA) patients. METHODS: A total of 53 RA patients, and 25 healthy individuals (control group) were enrolled. Rheumatoid arthritis patients were classified as in active phase (group 1; n=24) or in remission phase (group 2; n=29). Corneal biomechanical parameters including corneal hysteresis (CH), corneal resistance factor (CRF), corneal compensated intraocular pressure (IOPcc), and Goldmann-correlated IOP (IOPg) were measured with the Reichert Ocular Response Analyzer. Topographical measurements, including central corneal thickness (CCT), anterior chamber depth, iridocorneal angle, and corneal volume were measured using a Sirius corneal topographer. RESULTS: The mean CH was 9.43±1.17 mm Hg in group 1, 9.42±1.84 mm Hg in group 2, and 10.47±1.68 mm Hg in the control group (P=0.03). The mean IOPcc was 17.85±3.2 mm Hg in group 1, 17.95±3.49 mm Hg in group 2, and 15.36±3.11 mm Hg in the control group (P=0.008). The CH showed a significant positive correlation with CRF (P=0.000, r=0.809) and CCT (P=0.000, r=0.461), and a significant negative correlation with IOPcc (P=0.000, r=-0.469). CONCLUSIONS: Decrease in the mean CH measurements indicates that ultrastructural changes in the cornea may occur in the active phase, and these changes persist in the remission period. In addition, IOPcc is significantly affected by the corneal biomechanical properties. In RA patients, it is important to control the corneal parameters and IOP measurements against the irreversible changes on the optic nerve.

Relationship Between the Clinical Factors and Deviation Control in Intermittent Exotropia.

PURPOSE: To establish whether clinical factors were correlated with deviation control in intermittent exotropia. METHODS: This retrospective study included 54 patients with intermittent exotropia. The patient's sex, family history, age at first admission, best corrected visual acuity, refractive errors after cycloplegia, angles of ocular deviation at near and distance, and near, distance, and total deviation control were evaluated. Ocular deviation controls were determined according to the Mayo Clinic's office-based scale. Correlation analysis was performed between the deviation control and the determined clinical factors. RESULTS: Spearman correlation analyses revealed a mild correlation between age with total exotropia control score and age with the control of near exotropia control score (r = 0.320, P = .018 and r = 0.339, P = .012, respectively). The angle of deviation at near showed a significant moderate correlation between total exotropia control score and near exotropia control score (r = 0.523, P < .001 and r = 0.780, P < .001, respectively). The deviation angle at distance showed a mild correlation with distance exotropia control score and total exotropia control score (r = 0.423, P = .001 and r = 0.288, P = .034, respectively). The angle of deviation at distance showed a mild correlation with the angle of deviation at near (r = 0.359, P = .008). The deviation angle at distance was established as an independent factor for predicting total exotropia score (P = .037, P = .015, respectively). CONCLUSIONS: The high deviation angle correlates positively with poor deviation control. The distance deviation angle is an independent predictor of total deviation control for the first time in the literature. [J Pediatr Ophthalmol Strabismus. 2022;59(1):53-59.].

Effects of intracameral use of adrenalin solution with preservative on corneal endothelium.

OBJECTIVE: To evaluate the effects of injection of 1:100,000 dilution adrenalin with sodium bisulfite preservative on the corneal endothelium in phacoemulsification cataract surgery. METHODS: This retrospective study comprised 70 patients with age-related cataracts who had undergone phacoemulsification cataract surgery with intraocular lens (IOL) implantation without any surgical complications. In the adrenalin group, patients with intraoperative intracameral adrenalin use were included. The intracameral adrenalin was composed of 1 mL of 1:100,000 dilution adrenalin with sodium bisulfite preservative. The control group included patients who underwent surgery without any intracameral adrenaline use. There were 36 patients in the adrenalin group and 34 patients in the control group. Corneal endothelial density, endothelial cell morphology, and endothelial cell area were measured via specular microscopy both preoperatively and 3 months after surgery. The 2 groups were compared with regard to changes in specular microscopy measurements. RESULTS: The mean (+/- standard deviation) age was 66.51 +/- 8.32 years in the adrenalin group and 67.58 +/- 7.83 years in the control group. The difference in age between the 2 groups was not significant (p = .611). The preoperative mean corneal endothelial cell density was 2,270 +/- 286 cells/mm(2) in the adrenalin group and 2,226 +/- 260 cells/mm(2) in the control group, and the difference between the 2 groups was not statistically significant (p = .550). In the adrenalin group, the postoperative mean corneal endothelial cell density was 2,191 +/- 268 cells/mm(2). Although the postoperative mean cell density was lower than the preoperative mean cell density, the difference between the 2 measurements was not statistically significant (p = .117). In the control group, the postoperative mean corneal endothelial cell density was 2,169 +/- 272 cells/mm(2), and the difference between the preoperative and postoperative measurements was not statistically significant (p = .161). Comparisons of postoperative specular microscopy measurements between the adrenalin and control groups with regard to cell density, cell sizes, and cell shapes showed that there were no statistically significant differences in comparison of all parameters between the 2 groups. CONCLUSIONS: Intracameral injection of 1:100,000 dilution adrenalin with sodium bisulfite preservative is not toxic to corneal endothelium.

Design of ocular drug delivery platforms and in vitro - in vivo evaluation of riboflavin to the cornea by non-interventional (epi-on) technique for keratoconus treatment.

AIM: Keratoconus is a common and progressive eye disease characterized by thinning and tapering of the cornea. This degenerative eye disease is currently treated in the clinic with an interventional technique ("epi-off") that can cause serious side effects as a result of the surgical procedure. The aim of this project is to design innovative formulations for the development of a riboflavin-containing medicinal product to develop a non-invasive ("epi-on") keratoconus treatment as an alternative to current treatment modalities. METHODS: Nanostructured lipid carriers (NLCs) were successfully loaded with either riboflavin base of riboflavin-5-phosphate sodium and designed with either Stearylamine (positive charge) or Trancutol P (permeation enhancer). In vitro characterization studies, cytotoxicity and permeability studies were performed. Selected formulations and commercial preparations were applied and compared in ex-vivo corneal drug accumulation and transition studies. Furthermore, in vivo studies were performed to assess drug accumulation in the rat cornea and the corneal stability after NLC treatment was investigated via a biomechanical study on isolated rabbit corneas. RESULTS: Both in vitro and ex-vivo as well as in vivo data showed that from the prepared NLC formulations, the most effective formulation was riboflavin-5-phosphate sodium containing NLC with Transcutol P as permeation enhancer. It possessed the highest drug loading content, low accumulation in the cornea but high permeability through the cornea as well as the highest functional performance in corneal crosslinking. CONCLUSION: Topical application of riboflavin-5-phosphate sodium loaded NLC systems designed with permeation enhancer Transcutol P may act as a potential alternative for non-invasive keratoconus treatments.

Long-term effects of prostaglandin analogues on the anterior chamber depth of patients with primary open-angle glaucoma.

OBJECTIVE: To evaluate the effect of long-term application of bimatoprost and latanoprost on the anterior chamber depth of primary open-angle glaucoma patients. METHODS: The anterior chamber depth (ACD) and axial length (AL) of patients using prostaglandin analogues for open-angle glaucoma (group I) and an age- and gender-adjusted control group (group II) were measured by ultrasonography. Patients using bimatoprost and those using latanoprost were also compared in terms of ACD and AL. RESULTS: The mean ACD of group I (27 eyes of 27 subjects) was significantly lower than that of group II (30 eyes of 30 subjects) (p = .012). Similarly, the ratio of ACD to AL was significantly lower in group I compared with group II (p = .001). The ACDs of patients using bimatoprost or latanoprost and the control group were not significantly different by Kruskal-Wallis test (p = .056), but the differences of these 3 groups in ACD/AL ratios were significant (p = .004). When the Mann Whitney U test was used for pairwise comparison, there was a significant difference between the control group and the patients using latanoprost or bimatoprost in terms of the ACD/AL ratio (p = .008 for each). There was no difference between the patients using latanoprost and those using bimatoprost in terms of the ACD/AL ratio (p = .4). CONCLUSION: The ACD of patients on prolonged therapy with prostaglandin analogues seems to be lower than than that of the control group. However, prospective long-term studies on large number of subjects are needed to evaluate the effect of each type of prostaglandin on ocular structures.

Evaluating the Effect of Intravitreal Ranibizumab on Retrobulbar Hemodynamics by Color Doppler Ultrasonography in Neovascular AMD.

BACKGROUND AND OBJECTIVE: To evaluate changes in retrobulbar blood flow by using color Doppler ultrasonography (CDUS) after intravitreal ranibizumab injection in patients with neovascular age-related macular degeneration (AMD). PATIENTS AND METHODS: Eighteen patients who had undergone intravitreal ranibizumab (0.05 mg/0.05 mL) injection due to choroidal neovascular membrane (CNVM) were included in the study. Contralateral eyes of the patients were also analyzed. Peak systolic velocity (PSV), end diastolic velocity (EDV), pulsatility index (PI), and resistivity index (RI) were measured from the ophthalmic artery (OA), central retinal artery (CRA), lateral posterior ciliary artery (LPCA), and medial posterior ciliary artery (MPCA) for all patients pre-injection, and at 1 day, 1 week, and 1 month after ranibizumab injection. RESULTS: The mean age of the 18 patients included in the study was 66.94 years (± 8.3 years). Of these 18 patients, eight were female and 10 were male. After Bonferroni's correction for multiple comparisons was carried out, there were significant differences only in some values of LPCA; these included the decrease in EDV and an increase in PI values of LPCA between the pre-injection and post-injection of the first month measurements in uninjected eyes (P = .002, P = .002), and a decrease in PI value of LPCA between post-injection first day and first week measurements in injected eyes (P = .004). There were no statistically significant differences in other parameters. CONCLUSION: Ocular blood flow velocities may change after intravitreal ranibizumab injection in patients with CNVM. [Ophthalmic Surg Lasers Imaging Retina. 2019;50:437-443.].

Transscleral Delivery of Bevacizumab-Loaded Chitosan Nanoparticles.

Purpose: The aim of this study was to synthesize bevacizumab-loaded nanoparticles and evaluate their effects on the treatment of posterior segment diseases via subtenon injections. Methods: Bevacizumab-loaded chitosan nanoparticles (BLCNs) were synthesized by the ionic gelation method, and their physicochemical characteristics and in vitro release profile were studied. The BLCNs were characterized using atomic force microscopy (AFM), FTIR spectroscopy, dynamic light scattering, and scanning electron microscopy. The BLCNs were delivered into rabbits' eyes via posterior subtenon injections. An immunohistochemical evaluation of the ocular tissues was performed, and the vitreous humor and serum bevacizumab levels were measured by ELISA. Results: Bevacizumab-loaded chitosan nanoparticles with a diameter of 80 to 380 nm were prepared and characterized. In vitro studies showed that after the first 5 days of the experiment, a significant increase in the drug release maintained the desired drug dosage for 3 weeks. Immunohistochemical in vivo studies revealed that there were BLCNs penetrating through the sclera. Furthermore, the intravitreal bevacizumab concentration reached a maximum concentration of 18 µg/ml, and it decreased to 6 µg/ml after only a week. Conclusion: The results revealed that subtenon injection of BLCNs is a promising alternative to intravitreal injections. In addition to the ELISA studies, immunohistochemical experiments confirmed that BLCNs enable transscleral bevacizumab penetration, and BLCN usage may provide the required bevacizumab levels for the treatment of posterior segment diseases.

Comparison of the pupillometry during videonystagmography in asymmetric pseudoexfoliation patients.

PURPOSE: We aimed to evaluate the dynamic function of iris muscle in asymmetric pseudoexfoliation patients by videonystagmography. METHODS: 15 patients with asymmetric pseudoexfoliation and 15 control subjects were included. The function of iris muscle was assessed by the pupillometry test of the videonystagmography by calculating the percent of change in pupillary diameter in unit time during fixation to an accommodative target, light reaction, convergence, and divergence. RESULTS: There were significant differences between groups in the reaction during fixation (p: 0.01), in light reaction (p: 0.014), and in divergence-induced mydriasis (p: 0.003). In all of these, the difference between control eyes and pseudoexfoliative eyes of patients with PXS was significant. CONCLUSIONS: Pupillometry seems to be a promising noninvasive method to detect the clinical signs of PXS and may be useful for an accurate diagnosis.

Neurotrophic ulcer after extra-capsular cataract operation.

Although neurotrophic ulcers due to herpes zoster are seldom, there may be challenging cases. Especially neurotrophic corneal ulcers after cataract operations should arise the possibility of a previous herpes zoster attack and the treatment plan should be prepared accordingly. This case highlights the importance of thorough evaluation of cataract patients in order not to miss a previous diagnosis of herpes.

Intravitreal PRN ranibizumab treatment for macular edemadue to branch retinal vein occlusion.

BACKGROUND/AIM: To evaluate the effect of intravitreal pro re nata (PRN) ranibizumab treatment from the start on the best-corrected visual acuity (BCVA) and the central retinal thickness (CRT) in macular edema (ME) due to branch retinal vein occlusion (BRVO). MATERIALS AND METHODS: Patients with ME secondary to BRVO, who were treated on a PRN basis after a single intravitreal ranibizumab injection, were retrospectively evaluated. The main outcome measures were changes in BCVA and CRT as measured by optical coherence tomography. RESULTS: The number of injections over 6 months was 2.43 ± 1.16. The mean BCVA of the patients was 0.84 ± 0.10 logMAR at baseline and 0.41 ± 0.06 at the 6th month (P < 0.001). Mean BCVA of the ischemic BRVO group was 1.06 ± 0.68 logMAR at baseline and 0.44 ± 0.30 logMAR at the 6th month (P < 0.05). Similarly, the mean BCVA of the nonischemic BRVO group was 0.77 ± 0.53 logMAR at baseline and 0.41 ± 0.36 logMAR at the 6th month (P < 0.05). Between groups, there was no significant difference in mean BCVA at any examination. CONCLUSION: Intravitreal ranibizumab is a safe and effective treatment option for ME due to ischemic and nonischemic BRVO using PRN from the start.

Cyclotorsion measurement using scleral blood vessels.

BACKGROUND AND OBJECTIVES: Measurements of the cyclotorsional movement of the eye are crucial in refractive surgery procedures. The planned surgery pattern may vary substantially during an operation because of the position and eye movements of the patient. Since these factors affect the outcome of an operation, eye registration methods are applied in order to compensate for errors. While the majority of applications are based on features of the iris, we propose a registration method which uses scleral blood vessels. Unlike previous offline techniques, the proposed method is applicable during surgery. METHODS: The sensitivity of the proposed registration method is tested on an artificial benchmark dataset involving five eye models and 46,305 instances of eye images. The cyclotorsion angles of the dataset vary between -10° and +10° at 1° intervals. Repeated measurements and ANOVA and Cochran's Q tests are applied in order to determine the significance of the proposed method. Additionally, a pilot study is carried out using data obtained from a commercially available device. The real data are validated using manual marking by an expert. RESULTS AND CONCLUSIONS: The results confirm that the proposed method produces a smaller error rate (mean = 0.44 ± 0.41) compared to the existing method in [1] (mean = 0.64 ± 0.58). A further conclusion is that feature extraction algorithms affect the results of the proposed method. The SIFT (mean = 0.74 ± 0.78), SURF64 (mean = 0.56 ± 0.46), SURF128 (mean = 0.57 ± 0.48) and ASIFT (mean = 0.29 ± 0.25) feature extraction algorithms were examined; the ASIFT method was the most successful of these algorithms. Scleral blood vessels are observed to be useful as a feature extraction region due to their textural properties.

Long-Term Clinical Outcomes of Myopic Patients Having Thin Residual Corneal Thickness after Excimer Laser Surface Ablation.

PURPOSE: To investigate and compare the long-term safety, efficacy, and accuracy of PRK (photorefractive keratectomy) and LASEK (laser epithelial keratomileusis) in myopic corneas having residual corneal thickness less than 400 micron meters (µm). METHODS: The medical reports of the patients who had undergone excimer laser surface ablation between 2007-2011 and had a residual corneal thickness less than 400 µm were retrospectively reviewed. RESULTS: Forty-two eyes of 42 patients with a mean age of 28.79±7.76 years were enrolled into the study. Twenty-two PRK and 20 LASEK procedures were performed. The mean follow-up time was 45.00±11.80 months. At the end of follow-up, no ectasia was detected. Nineteen percent of eyes had trace haze. No eyes lost any lines in corrected distance visual acuity. Eighty-one percent of the patients had an uncorrected distance visual acuity better than 20/40. The regression rate was 16.7%. Sixty-two percent of eyes were within ±1.00 D. The safety and efficacy indexes were 1.19±0.42 and 1.00±0.40, respectively. There was not any difference between LASEK and PRK regarding achieved spherical equivalent refraction, haze ratio, visual acuity, safety, efficacy, and regression. CONCLUSIONS: Both PRK and LASEK are safe and effective in myopic corneas having thin residual thickness.

The Effect of Perioperative Topical Ketorolac 0.5% on Macular Thickness after Uneventful Phacoemulsification.

BACKGROUND: To evaluate the effects of topical 0.5% ketorolac treatment combined with topical steroids on macular thickness in cases who had uneventful phacoemulsification surgery. METHODS: 58 eyes of 58 consecutive cases were included. The mean foveal thickness (MFT), parafoveal thickness (ParaFT), and perifoveal thickness (PeriFT) measurements were performed with optical coherence tomography (RTVue-100, Optovue, Fremont, CA, USA) preoperatively and at postoperative 1 week, 1 month, and 2 months. All cases received topical 0.1% dexamethasone postoperatively. Randomly selected cases additionally received topical 0.5% ketorolac, which started 2 days prior to surgery. Cases who received both topical steroids and ketorolac formed group 1 and subjects who received only topical steroids formed group 2. RESULTS: The increase in mean MFT at the 1st week, 1st month, and 2nd months after surgery in group 1 was significantly lower than group 2 (P = 0.008, P ≤ 0.001, and P ≤ 0.001, resp.). In group 1, the increase in mean ParaFT and PeriFT was significantly lower than group 2 at the 1st and 2nd months of the surgery (P < 0.05 for all variables). CONCLUSIONS: Topical ketorolac combined with steroids is highly efficacious in order to prevent increment in thickness on each part of the macula even after an uneventful phacoemulsification surgery comparing to steroid monotheraphy.

Choroidal Thickness in Childhood Obesity.

BACKGROUND AND OBJECTIVE: To evaluate the effects of obesity on choroidal thickness (CT) in childhood. PATIENTS AND METHODS: Forty-four patients with obesity (study group) and 42 healthy children (control group) were enrolled in the study. Subjects underwent a complete ocular examination. The mean CT was measured by enhanced depth imaging optical coherence tomography (EDI-OCT). Body mass index (BMI) was calculated. RESULTS: Mean BMI value was 31.8 ± 1.9 in the study group and 19.8 ± 4.4 in the control group. The mean subfoveal CT value 385.77 µm ± 6.09 µm in the study group and 348.43 µm ± 73.21 µm in the control group. There was a significant difference between the study and control groups with regard to subfoveal CT (P = .017). Subfoveal CT and BMI were positively correlated (r = 0.288; P = .004). CONCLUSIONS: CT increases in childhood obesity. Findings revealed that adiposity causes a significant increase in CT, and it may be related to ocular complications. [Ophthalmic Surg Lasers Imaging Retina. 2017;48:10-17.].

Factors Influencing Progression of Keratoconus 2 Years After Corneal Collagen Cross-Linking in Pediatric Patients.

PURPOSE: To assess the preoperative patient characteristics that may predict outcomes of keratoconus 2 years after corneal collagen cross-linking (CXL) in pediatric patients with keratoconus. METHODS: This retrospective study included 72 eyes of 52 consecutive patients with keratoconus under the age of 18 with 2-year follow-up after CXL. Subgroup analysis and cutoff values were determined as per age (<14 and ≥14 years), sex, baseline uncorrected and corrected distance visual acuities (UCVA, CDVA; <0.8 and ≥0.8 logMAR), topographic cone location (central and paracentral), maximum keratometry (K-max, <54 and ≥54 diopters), and corneal thickness at the thinnest point (thCT) (<450 and ≥450 µm) to evaluate the associations between preoperative patient characteristics and outcomes of CXL treatment in terms of K-max. Postoperative progression in K-max was defined as steepening of 1.0 diopter or more. RESULTS: Average age of patients was 14.8 ± 2.2 (9-17) years. After 2 years, the mean UCVA significantly improved and the mean thCT significantly decreased in all patients (P = 0.023, P < 0.001, respectively). The K-max in patients with paracentral cones and/or with thCT less than 450 µm were more likely to progress (cone location: P = 0.023, odds ratio = 3.21, 95% confidence interval, 1.17-8.72; thCT: P = 0.008, odds ratio = 4.54, 95% confidence interval, 1.46-14.14). Age, sex, baseline UCVA, CDVA, and K-max did not present any significant effect on progression of CXL after treatment (P > 0.05 for all variables). CONCLUSIONS: In pediatric patients with keratoconus, cone location and the baseline thinnest corneal thickness seem to affect the success rate of CXL treatment after 2-year follow-up.

Investigation of the Efficacy of the Cone Location and Magnitude Index in the Diagnosis of Keratoconus.

PURPOSE: The aim of this study was to investigate the sensitivity, specificity, and accuracy of The Cone Location and Magnitude Index (CLMI) in keratoconus diagnosis. METHODS: 301 eyes of 159 keratoconus patients and 394 eyes of 265 refractive surgery candidates as a control group were enrolled in this retrospective clinical study. CLMI was compared with keratometric corneal topography parameters, wavefront aberrations, and pachymetry data derived from optical coherence tomography using independent sample t-tests and ROC curves. Logistic regression analysis was applied to determine the most accurate parameter in keratoconus diagnosis. Pearson's correlation analysis was used to determine the correlation between CLMI and the other measurements. RESULTS: Average axial CLMI (aCLMI) was 8.19 ± 6.15 D in the keratoconus group and 0.83 ± 0.62 D in the control group (p = 0.001). aCLMI had the greatest sensitivity (89%), specificity (94%), and accuracy (92%) for the keratoconus diagnosis at the best cut-off point of 1.82 according to the ROC curve. Logistic regression analysis selected aCLMI as the most accurate measurement among the other parameters (accuracy 92.8%). aCLMI showed strongest correlations with coma-like aberrations (r = 0.881), total high-order aberrations (r = 0.858), and vertical coma (r = -0.814), respectively. CONCLUSION: CLMI is a robust index for screening keratoconus with high sensitivity, specificity, and accuracy.

Urgent Therapeutic Grafting of Platelet-Rich Fibrin Membrane in Descemetocele.

PURPOSE: To report the clinical and histopathological results of a novel autologous scaffold grafting, platelet-rich fibrin (PRF) membrane, in cases with descemetocele. METHODS: Three patients with severe corneal stromal melting and central descemetocele caused by neurotrophic keratopathy and infective keratitis underwent PRF membrane grafting on the central cornea for the prevention of imminent corneal perforation. After a quiescent 3-month period, penetrating keratoplasty and cataract extraction were performed for visual rehabilitation in 1 patient and host corneal tissue was examined histopathologically. RESULTS: Pain was significantly relieved, conjunctival inflammation was markedly resolved, and the central descemetocele area became thicker with scar formation in all patients. Histopathological examination revealed fibrosis formation over the descemetocele area without any tissue gap. Newly formed tissue containing irregular corneal lamellae covered the fibrosis formation and accounted for the prevention of perforation. CONCLUSIONS: Temporary PRF membrane grafting may be an alternative intervention to avoid impending corneal perforation in cases with severe descemetocele.

A Novel Technique for Conjunctivoplasty in a Rabbit Model: Platelet-Rich Fibrin Membrane Grafting.

Purpose. To investigate the effect of platelet-rich fibrin (PRF) membrane on wound healing. Methods. Twenty-four right eyes of 24 New Zealand rabbits equally divided into 2 groups for the study design. After the creation of 5 × 5 mm conjunctival damage, it was secured with PRF membrane, which was generated from the rabbit's whole blood samples in PRF membrane group, whereas damage was left unsutured in the control group. Three animals were sacrificed in each group on the 1st, 3rd, 7th, and 28th postoperative days. Immunohistochemical (IHC) stainings and biomicroscopic evaluation were performed and compared between groups. Results. PRF membrane generated significant expressions of vascular endothelial growth factor (VEGF), transforming growth factor-beta (TGF-ß), and platelet-derived growth factor (PDGF) in the early postoperative period. However, the IHC evaluation allowed showing the excessive staining at day 28, in control group. Biomicroscopic evaluation revealed complete epithelialization in PRF membrane group, but none of the cases showed complete healing in the control group. Conclusions. This experimental study showed us the beneficial effects of the PRF membrane on conjunctival healing. Besides its chemical effects, it provides mechanical support as a scaffold for the migrating cells that are important for ocular surface regeneration. These overall results encourage us to apply autologous PRF membrane as a growth factor-enriched endogenous scaffold for ocular surface reconstruction.