Influence of cyclopentolate hydrochloride on corneal biomechanical properties in healthy individuals.

OBJECTIVE: This observational study aims to investigate the effects of cyclopentolate hydrochloride (1%) on corneal biomechanical properties, with the ocular response analyzer (ORA), in healthy individuals. METHODS: Corneal hysteresis (CH), corneal resistance factor (CRF), Goldmann-correlated intraocular pressure (IOPg), and corneal-compensated intraocular pressure (IOPcc) measurements of 36 (15 female and 21 male) healthy individuals, before and after 45 min of 1% cyclopentolate hydrochloride instillation, were performed by the ORA. RESULTS: The mean CH and IOPcc measurements of the eyes were 10.63±1.17 mm Hg and 15.15±2.69 mm Hg, precycloplegia, and 11.09±1.32 mm Hg and 14.16±2.77 mm Hg, postcycloplegia, respectively. The differences between the precycloplegia and postcycloplegia in both measurements were statistically significant (P=0.031, P=0.016, respectively; paired t test). The mean CRF and mean IOPg measurements of the eyes were 10.40±1.16 mm Hg and 14.83±2.56 mm Hg, precycloplegia, and 10.61±1.33 mm Hg and 14.25±2.65 mm Hg, postcycloplegia, respectively. The differences between the precycloplegia and postcycloplegia measurements of the eyes were insignificant (P=0.264 and P=0.100, respectively; paired t test). CONCLUSIONS: A 1% cyclopentolate hydrochloride instillation leads to significant changes in the CH values and IOPcc measurements. This should be taken into account during the evaluation of refractive surgery candidates and in clinical conditions where ORA measurements are considered in the diagnosis and follow-up.

Corneal axonal loss as an imaging biomarker of neurodegeneration in multiple sclerosis: a longitudinal study.

Background: Resourceful endpoints of axonal loss are needed to predict the course of multiple sclerosis (MS). Corneal confocal microscopy (CCM) can detect axonal loss in patients with clinically isolated syndrome and established MS, which relates to neurological disability. Objective: To assess corneal axonal loss over time in relation to retinal atrophy, and neurological and radiological abnormalities in MS. Methods: Patients with relapsing-remitting (RRMS) (n = 68) or secondary progressive MS (SPMS) (n = 15) underwent CCM and optical coherence tomography. Corneal nerve fibre density (CNFD-fibres/mm2), corneal nerve branch density (CNBD-branches/mm2), corneal nerve fibre length (CNFL-mm/mm2) and retinal nerve fibre layer (RNFL-µm) thickness were quantified along with neurological and radiological assessments at baseline and after 2 years of follow-up. Age-matched, healthy controls (n = 20) were also assessed. Results: In patients with RRMS compared with controls at baseline, CNFD (p = 0.004) and RNFL thickness (p < 0.001) were lower, and CNBD (p = 0.003) was higher. In patients with SPMS compared with controls, CNFD (p < 0.001), CNFL (p = 0.04) and RNFL thickness (p < 0.001) were lower. For identifying RRMS, CNBD had the highest area under the receiver operating characteristic (AUROC) curve (0.99); and for SPMS, CNFD had the highest AUROC (0.95). At follow-up, there was a further significant decrease in CNFD (p = 0.04), CNBD (p = 0.001), CNFL (p = 0.008) and RNFL (p = 0.002) in RRMS; in CNFD (p = 0.04) and CNBD (p = 0.002) in SPMS; and in CNBD (p = 0.01) in SPMS compared with RRMS. Follow-up corneal nerve loss was greater in patients with new enhancing lesions and optic neuritis history. Conclusion: Progressive corneal and retinal axonal loss was identified in patients with MS, especially those with more active disease. CCM may serve as an imaging biomarker of axonal loss in MS.

Corneal confocal microscopy identifies corneal nerve fibre loss and increased dendritic cells in patients with long COVID.

BACKGROUND/AIMS: Long COVID is characterised by a range of potentially debilitating symptoms which develop in at least 10% of people who have recovered from acute SARS-CoV-2 infection. This study has quantified corneal sub-basal nerve plexus morphology and dendritic cell (DC) density in patients with and without long COVID. METHODS: Forty subjects who had recovered from COVID-19 and 30 control participants were included in this cross-sectional comparative study undertaken at a university hospital. All patients underwent assessment with the National Institute for Health and Care Excellence (NICE) long COVID, Douleur Neuropathique 4 (DN4) and Fibromyalgia questionnaires, and corneal confocal microscopy (CCM) to quantify corneal nerve fibre density (CNFD), corneal nerve branch density (CNBD), corneal nerve fibre length (CNFL), and total, mature and immature DC density. RESULTS: The mean time after the diagnosis of COVID-19 was 3.7±1.5 months. Patients with neurological symptoms 4 weeks after acute COVID-19 had a lower CNFD (p=0.032), CNBD (p=0.020), and CNFL (p=0.012), and increased DC density (p=0.046) compared with controls, while patients without neurological symptoms had comparable corneal nerve parameters, but increased DC density (p=0.003). There were significant correlations between the total score on the NICE long COVID questionnaire at 4 and 12 weeks with CNFD (ρ=-0.436; p=0.005, ρ=-0.387; p=0.038, respectively) and CNFL (ρ=-0.404; p=0.010, ρ=-0.412; p=0.026, respectively). CONCLUSION: Corneal confocal microscopy identifies corneal small nerve fibre loss and increased DCs in patients with long COVID, especially those with neurological symptoms. CCM could be used to objectively identify patients with long COVID.

Traumatic hyphema in a patient with severe hemophilia A: Clinical features and management.

PURPOSE: To describe a case of traumatic hyphema in a patient with severe hemophilia A. CASE: We present a case of a 16-year-old boy with severe hemophilia A who presented to our ophthalmology department with total hyphema and elevated intraocular pressure 3 days after a history of blunt ocular trauma on his right eye. Due to the persistent intraocular pressure elevation and total hyphema despite medical intervention, an early anterior chamber washout was performed with the replacement of factor VIII preoperatively and postoperatively. Re-bleeding or any other complications were not experienced during surgery or postoperatively. At the first postoperative week, 20/20 visual acuity and a normal intraocular pressure without antiglaucoma medication was retained and remained stable during the 6-month follow-up. CONCLUSION: In such cases with hemophilia A, traumatic hyphema, and intraocular pressure elevation despite medical intervention, an early surgical clot removal under intense factor VIII replacement could be performed. In the early postoperative period, factor replacement should be resumed in order to avoid re-bleeding.

Monocyte/HDL Ratio and Lymphocyte/Monocyte Ratio in Patients with Pseudoexfoliation Syndrome.

Purpose: To evaluate the association between monocyte count/high-density lipoprotein (HDL) ratio (MHR) and lymphocyte count/monocyte count ratio (LMR) with pseudoexfoliation syndrome (PEXS) and pseudoexfoliation glaucoma (PEXG).Materials and Methods: A total of 63 participants included in the study. Participants were divided into three groups. Twenty-one patients with PEXS regarded as group 1, 21 patients with PEXG regarded as group 2 and 21 participants without PEXS or PEXG regarded as the control group. Blood parameters were accessed from file records and database retrospectively.Results: The mean MHRs were significantly higher in group 1 and group 2 (p = 0.003, p = 0.036) than the control group, whereas there was no difference between group 1 and group 2 (p = 0.686). The mean LMRs were lower in group 1 and group 2 than the control group but the difference was insignificant (p = 0.232).Conclusion: We found that there is an association between higher MHR and lower LMR with PEXS.

Progressive Loss of Corneal and Retinal Nerve Fibers in Patients With Multiple Sclerosis: A 2-Year Follow-up Study.

Purpose: To determine longitudinal alterations in corneal nerve fiber morphology, dendritic cell (DC) density, and retinal nerve fiber layer (RNFL) thickness over 2 years in patients with multiple sclerosis (MS). Methods: Thirty-one consecutive patients with relapsing-remitting MS (RRMS) underwent assessment of the Kurtzke Expanded Disability Status Scale (EDSS), Multiple Sclerosis Severity Score (MSSS), corneal confocal microscopy to quantify corneal subbasal nerve morphology and DC density, and spectral-domain optical coherence tomography to quantify RNFL thickness at baseline and after 2 years. Results: There was a significant reduction in corneal nerve fiber area (CNFA) (P = 0.003), nerve fiber width (CNFW) (P = 0.005), and RNFL thickness (P = 0.004) with an increase in EDSS (P = 0.01) over 2 years. The change in corneal nerve fiber density (CNFD) correlated with the change in EDSS (ρ = -0.468; P = 0.008), MSSS (ρ = -0.442; P = 0.01), DC density (ρ = -0.550; P = 0.001), and RNFL (ρ = 0.472; P = 0.007). The change in corneal nerve fiber length (CNFL) correlated with the change in EDSS (ρ = -0.445; P = 0.01) and MSSS (ρ = -0.490; P = 0.005). Furthermore, there was a significant decrease in CNFL (P < 0.001), CNFA (P = 0.02), CNFW (P = 0.04), corneal total branch density (P = 0.01), and RNFL thickness (P = 0.02) and a significant increase in DC density (P = 0.04) in patients with worsening EDSS (n = 15). Conclusions: Corneal confocal microscopy can be used to detect progressive corneal nerve fiber loss that relates to a progression of disability in patients with RRMS. Translational Relevance: Corneal confocal microscopy acts as a sensitive imaging biomarker for progressive nerve degeneration in patients with MS.

Evaluation of Pupillary Light Reflex in Amblyopic Eyes Using Dynamic Pupillometry

Objectives: To evaluate the pupillary light reflex responses in patients with unilateral strabismic and anisometropic amblyopia using dynamic pupillometry. Materials and Methods: A total of 102 eyes of 51 patients with unilateral amblyopia were included in this cross-sectional study. Of the 51 patients, 37 (72.5%) had strabismic amblyopia and 14 (27.5%) had anisometropic amblyopia. All patients underwent complete ophthalmological examination, and pupillary light reflex responses were measured using a computerized dynamic pupillometry system (MonPack One; Metrovision, France). Initial pupil diameter; the amplitude, latency, duration, and velocity of pupil contraction; and the latency, duration, and velocity of pupil dilation were recorded. Results obtained from the patients' amblyopic and normal fellow eyes were compared using paired-samples t-test and Wilcoxon signed rank test. Results: The mean age of the patients was 11.9±6.0 years. Amblyopic eyes had longer contraction latency (p=0.009), shorter contraction duration (p=0.002), and higher dilation velocity (p=0.033) compared to fellow eyes, while other parameters did not show significant differences. In subgroup analysis, eyes with strabismic amblyopia had longer contraction latency (p=0.006) and shorter contraction duration (p=0.017), while eyes with anisometropic amblyopia had shorter contraction duration (p=0.030) when compared with fellow eyes. Conclusion: In this study, the objective records obtained by dynamic pupillometry showed that pupillary light reflex responses are affected in amblyopic eyes. This finding may shed light on unclear aspects of the pathophysiology of amblyopia.

Analysis of Peripapillary Choroidal Thickness in Unilateral Amblyopia.

PURPOSE: To evaluate the peripapillary choroidal thickness (CT) in children with unilateral amblyopia using spectral-domain optical coherence tomography (SD-OCT). METHODS: One hundred and six eyes of 53 children with unilateral amblyopia and 20 eyes of 20 children with normal vision were involved in this study. Of the 53 children with unilateral amblyopia, 29 (54.7%) had hyperopic anisometropic amblyopia and 24 (45.3%) had strabismic amblyopia. Peripapillary CT was measured from 6 mm length radial B-scans at the optic nerve head using the enhanced depth imaging program of an SD-OCT (Heidelberg Engineering, Germany). Age, sex, refractive error, and best-corrected visual acuity were also recorded. RESULTS: The average peripapillary CT was greater in amblyopic eyes than in the fellow eyes of the children with amblyopia (P = 0.002), and control eyes (P < 0.001). There was no significant difference between the fellow eyes of children with amblyopia and the control eyes (P = 0.158). The average peripapillary CT was negatively correlated with axial length (AL) in amblyopic eyes (r = -0.381; P = 0.005) and fellow eyes (r = -0.392; P = 0.004) but not in control eyes (r = -0.232; P = 0.325). After adjustment for the possible effects of AL, the average peripapillary CT in amblyopic eyes was still greater than in fellow eyes (P = 0.014) and control eyes (P = 0.022). CONCLUSION: The peripapillary choroid of eyes with amblyopia was thicker than that of the fellow eyes and control eyes. No significant difference was observed between fellow eyes and control eyes.

The Frequency and Causes of Blindness in a Rural Region of Central Anatolia of Turkey.

OBJECTIVE: This study aimed to evaluate the frequency and primary causes of blindness in adults aged 18 years and more in Sarikaya rural region of Yozgat, Turkey, to contribute to the epidemiologic information about blindness in our country. MATERIALS AND METHODS: Patients who were examined between October 2016 and March 2017 in Sarikaya State Hospital, Clinic of Ophthalmology, were prospectively investigated. Demographic and ophthalmic examination data, presented visual acuities (VA), primary causes of blindness, and monocular blindness were recorded. Blindness was defined as presented visual acuities (VA) definition of World Health Organization criteria. RESULTS: A total of 3423 participants, aged 18-96 years, were examined. Among them, 1887 participants (55%) were female and 1536 (45%) were male. The frequency of blindness was 1.5% (95% CI: 1.1%-2.0%); and cataract was the primary cause of blindness (42%). Age-related macular degeneration (21%) and uncorrected refractive error (13%) were the next main causes of blindness. The frequency of monocular blindness was 4% (95% CI: 3.8%-5.2%), and cataract (27%) followed by phthisis bulbi/evisceration (13%) and glaucoma (12%) were the leading causes of monocular blindness. CONCLUSION: In this rural region of Central Anatolia, the primary cause of blindness and monocular blindness was an unoperated cataract. The patterns of age-specific causes of blindness are variable, but most of them are avoidable or treatable. Thus, awareness should be increased in societies, and people should be prevented from blindness with health-care programs in rural regions of developing countries.

Corneal confocal microscopy detects corneal nerve damage and increased dendritic cells in Fabry disease.

Fabry disease is characterised by neuropathic pain and accelerated vascular disease. This study evaluates the utility of corneal confocal microscopy (CCM) to non-invasively quantify corneal nerve and endothelial cell morphology and dendritic cell (DC) density in relation to disease severity in subjects with Fabry disease. Seventeen consecutive participants with Fabry disease and 17 healthy control subjects were included in this cross-sectional study. Fabry disease severity was measured using the Mainz Severity Score Index (MSSI). Central corneal sensitivity was assessed with a contact corneal esthesiometer. There was a significant reduction in the corneal sensitivity (5.75 [5.25-6.00] vs. 6.00 [6.00-6.00] cm, P = 0.014), nerve fiber density (NFD) (26.4 ± 10.1 vs. 33.7 ± 7.9 fibers/mm2, P = 0.025) and nerve fiber length (NFL) (15.9 ± 3.4 vs. 19.5 ± 4.4 mm/mm2, P = 0.012) and an increase in DC density (38.3 [17.5-97.3] vs. 13.5 [0-29.4] cells/mm2, P = 0.004) in subjects with Fabry disease compared to the healthy control subjects. The total MSSI score correlated with NFD (ρ = -0.686; P = 0.006), NFL (ρ = -0.692; P = 0.006), endothelial cell density (ρ = -0.511; P = 0.036), endothelial cell area (ρ = 0.514; P = 0.036) and α-galactosidase A enzyme activity (ρ = -0.723; P = 0.008). This study demonstrates reduced corneal sensitivity, corneal nerve fiber damage and increased DCs in subjects with Fabry disease.

In Vivo Confocal Microscopic Evaluation of Corneal Nerve Fibers and Dendritic Cells in Patients With Behçet's Disease.

Central and peripheral nervous system involvement may occur during the course of Behçet's disease (BD). In vivo corneal confocal microscopy (CCM) can detect corneal small fiber damage and immune cell density. The aim of this study was to assess central corneal sensitivity, corneal subepithelial nerve plexus morphology and dendritic cell (DC) density in patients with BD. Forty-nine consecutive patients with BD and 30 healthy control subjects were included in this cross-sectional study conducted at a tertiary referral university hospital. Central corneal sensitivity was measured using the contact corneal esthesiometer (Cochet-Bonnet; Luneau, France). The laser scanning CCM (Heidelberg, Germany) was used to quantify corneal nerve fiber density (NFD), nerve branch density (NBD), nerve fiber length (NFL), and DC density. There was a significant reduction in NFD (P = 0.001) and NFL (P = 0.031) and an increase in DC density (P = 0.038) in patients with BD compared to healthy controls, whereas corneal sensitivity (P = 0.066) and NBD (P = 0.067) did not differ significantly. There was no difference in corneal sensitivity, corneal nerve parameters, or DC density between BD patients with [n = 18 (36.7%)] and without a previous history of uveitis (P > 0.05 for all). Disease duration [median (IQR), 6.5 (4.0-14.5) years] correlated with corneal sensitivity (ρ = -0.463; P = 0.001) and NFD (ρ = -0.304; P = 0.034) and corneal sensitivity correlated with NFD (ρ = 0.411; P = 0.003) and NFL (ρ = 0.295; P = 0.039) in patients with BD. CCM demonstrates corneal sub-basal nerve fiber loss and increased DC density, providing a non-invasive ophthalmic means to identify peripheral neuropathy and inflammation in patients with BD.

Use of Corneal Confocal Microscopy to Detect Corneal Nerve Loss and Increased Dendritic Cells in Patients With Multiple Sclerosis.

Importance: Multiple sclerosis (MS) is characterized by demyelination, axonal degeneration, and inflammation. Corneal confocal microscopy has been used to identify axonal degeneration in several peripheral neuropathies. Objective: To assess corneal subbasal nerve plexus morphologic features, corneal dendritic cell (DC) density, and peripapillary retinal nerve fiber layer (RNFL) thickness in patients with MS. Design, Setting, and Participants: This single-center, cross-sectional comparative study was conducted at a tertiary referral university hospital between May 27, 2016, and January 30, 2017. Fifty-seven consecutive patients with relapsing-remitting MS and 30 healthy, age-matched control participants were enrolled in the study. Corneal subbasal nerve plexus measures and DC density were quantified in images acquired with the laser scanning in vivo corneal confocal microscope, and peripapillary RNFL thickness was measured with spectral-domain optical coherence tomography. Main Outcomes and Measures: Corneal nerve fiber density, nerve branch density, nerve fiber length, DC density, peripapillary RNFL thickness, and association with the severity of neurologic disability as assessed by the Kurtzke Expanded Disability Status Scale (score range, 0-10; higher scores indicate greater disability) and Multiple Sclerosis Severity Score (score range, 0.01-9.99; higher scores indicate greater severity). Results: Of the 57 participants with MS, 42 (74%) were female and the mean (SD) age was 35.4 (8.9) years; of the 30 healthy controls, 19 (63%) were female and the mean (SD) age was 34.8 (10.2) years. Corneal nerve fiber density (mean [SE] difference, -6.78 [2.14] fibers/mm2; 95% CI, -11.04 to -2.52; P = .002), nerve branch density (mean [SE] difference, -17.94 [5.45] branches/mm2; 95% CI, -28.77 to -7.10; P = .001), nerve fiber length (mean [SE] difference, -3.03 [0.89] mm/mm2; 95% CI, -4.81 to -1.25; P = .001), and the mean peripapillary RNFL thickness (mean [SE] difference, -17.06 [3.14] µm; 95% CI, -23.29 to -10.82; P < .001) were reduced in patients with MS compared with healthy controls. The DC density was increased (median [interquartile range], 27.7 [12.4-66.8] vs 17.3 [0-28.2] cells/mm2; P = .03), independent of a patient's history of optic neuritis. Nerve fiber density and RNFL thickness showed inverse associations with the Expanded Disability Status Scale (ρ = -0.295; P = .03 for nerve fiber density and ρ = -0.374; P = .004 for RNFL thickness) and the Multiple Sclerosis Severity Score (R = -0.354; P = .007 for nerve fiber density and R = -0.283; P = .03 for RNFL thickness), whereas other study measures did not. Conclusions and Relevance: These data suggest that corneal confocal microscopy demonstrates axonal loss and increased DC density in patients with MS. Additional longitudinal studies are needed to confirm the use of corneal confocal microscopy as an imaging biomarker in patients with MS.

Effects of panretinal laser photocoagulation on the corneal nerve plexus and retinal nerve fiber layer in retinal vein occlusion.

PURPOSE: To determine the effects of panretinal photocoagulation (PRP) on corneal sub-basal nerve plexus (SBNP) and peripapillary retinal nerve fiber layer (RNFL) thickness in patients with unilateral central retinal vein occlusion (CRVO) who had previously undergone PRP treatment. METHODS: Sixty-four eyes of 32 patients (19 male, 13 female) with unilateral ischemic type CRVO who had undergone PRP treatment at least 6 months previously were included in this cross-sectional study. The laser scanning in vivo corneal confocal microscope was used to determine corneal SBNP parameters. The peripapillary RNFL thickness was assessed with spectral-domain optical coherence tomography. Data obtained from the PRP-treated eyes were compared with those of the fellow unaffected eyes. RESULTS: The mean age of patients was 63.5 ± 10.7 years (range 45-85 years). The mean nerve fiber density (NFD), nerve branch density, and nerve fiber length (NFL) were significantly lower in PRP-treated eyes compared with fellow eyes (p<0.001 for all). Average peripapillary RNFL thickness was significantly lower in PRP-treated eyes than in fellow eyes (p = 0.007). The NFD and NFL showed a modest but significant positive correlation with average peripapillary RNFL thickness (r = 0.310, p = 0.013 and r = 0.272, p = 0.030, respectively). CONCLUSIONS: Significant reductions in corneal SBNP parameters and average peripapillary RNFL thickness were observed in the eyes of patients receiving PRP for the treatment of ischemic CRVO.

Unilateral Recurrent Anterior Uveitis as the Presenting Sign of Bladder Carcinoma.

A 79-year-old male patient was followed for unilateral uveitis with 3 attacks in 10 months, despite initial improvement with steroid therapy. The patient had visual acuity (VA) of counting fingers in right eye, hypopyon and vitritis with no chorioretinal lesions. The left eye was normal. The patient was evaluated for intraocular foreign body, intraocular lymphoma and associated systemic disease and malignancy. Computed tomography of the abdomen showed a mass in the bladder. Biopsy confirmed bladder carcinoma. After resection of the mass, intraocular inflammation improved completely and no attack was noted in the follow-up. In his last examination, two years after the operation, VA was light perception; seclusio pupilla and mature cataracts were seen on biomicroscopy. There was no sign of vitritis on ocular ultrasonography. Evidence is discussed that suggests a link and potential etiology between refractory uveitis with hypopyon and bladder carcinoma. This is the first case of unilateral recurrent uveitis with hypopyon as the initial presenting sign of bladder carcinoma.

Ophthalmic manifestations in recently diagnosed childhood leukemia.

PURPOSE: To determine the prevalence and the pattern of ocular involvement in children with leukemia at the time of diagnosis. METHODS: The data of patients with leukemia who underwent complete ophthalmic examination at the time of diagnosis between January 2005 and December 2014 were retrospectively reviewed. Demographic data, type of leukemia, ocular findings, blood parameters, and duration of follow-up were analyzed. RESULTS: A total of 185 patients (111 male and 74 female) were included in the study, with a median age of 6.0 years (range 0.5-18.0 years) and a median follow-up time of 36.0 months (range 0.5-108.0 months). Ocular signs were present in 24.3% of the patients at the time of diagnosis and 37.8% of them were symptomatic. The prevalence of ocular involvement was 20.4% in patients with acute lymphocytic leukemia (ALL) and 36.4% in patients with acute myelocytic leukemia (AML) (p = 0.051). Fatality rate was significantly higher in subjects with AML compared with ALL (p = 0.019), but was not significantly different between patients with and without ocular involvement (p = 0.166). There were no significant differences in hemoglobin levels, white blood cell counts, or platelet counts between patients with ALL and AML. Platelet counts were significantly lower in patients with ocular signs compared with subjects without ocular involvement (p = 0.012), while hemoglobin levels and white blood cell counts did not differ significantly. CONCLUSIONS: Various ocular signs may be present at the time of diagnosis in childhood leukemia, even in patients without any symptoms. Routine ophthalmic examination should be performed in recently diagnosed children with leukemia.

Six-month outcomes of corneal crosslinking with dextran-free isotonic riboflavin solution.

PURPOSE: To analyze the short-term clinical and topographic outcomes in patients with keratoconus after corneal collagen cross-linking treatment (CXL) with dextran-free isotonic riboflavin solution. METHODS: In this retrospective case series, 26 eyes from 26 patients with keratoconus were studied. The best corrected visual acuity (BCVA) and refractive and topographic findings were analyzed at a 6-month follow-up. RESULTS: The mean BCVA (Snellen lines) values before and 1, 3, and 6 months after CXL were 0.51 ± 0.2, 0.48 ± 0.2, 0.57 ± 0.2, and 0.64 ± 0.2, respectively, and the difference between the preoperative and 6-month values was statistically significant (p=0.006). The mean spherical equivalent refraction decreased from -5.6 ± 2.4 diopters (D) preoperatively to -5.0 ± 2.1 D, and mean simulated keratometry decreased from 48.5 ± 2.5 D to 47.8 ± 2.6 D at 6 months. (p=0.145 and p=0.001, respectively). In addition, the maximum keratometry decreased progressively and significantly from the preoperative value during follow-up (p=0.003). The central and minimal corneal thicknesses, including those of the epithelium, also decreased from 442.8 ± 25.6 µm and 430.5 ± 23.9 µm preoperatively to 420.7 ± 31.8 µm and 409.3 ± 28.7 µm at the most recent follow-up (p<0.001), respectively. No intraoperative or postoperative complications were observed. CONCLUSIONS: CXL with dextran-free isotonic riboflavin solution appears to be a safe treatment alternative for keratoconus and yields sustained short-term improvements in visual acuity, keratometric readings, and corneal thickness. However, long-term results are needed to confirm these outcomes.

In vivo corneal confocal microscopic analysis in patients with keratoconus.

AIM: To quantify corneal ultrastructure using laser scanning in vivo confocal microscopy (IVCM) in patients with keratoconus and control subjects. METHODS: Unscarred corneas of 78 keratoconic subjects without a history of contact lens use and 36 age-matched control subjects were evaluated with slit-lamp examination (SLE), corneal topography and laser scanning IVCM. One eye was randomly chosen for analysis. Anterior and posterior stromal keratocyte, endothelial cell and basal epithelial cell densities and sub-basal nerve structure were evaluated. RESULTS: IVCM qualitatively demonstrated enlarged basal epithelial cells, structural changes in sub-basal and stromal nerve fibers, abnormal stromal keratocytes and keratocyte nuclei, and pleomorphism and enlargement of endothelial cells. Compared with control subjects, significant reductions in basal epithelial cell density (5817±306 cells/mm(2) vs 4802±508 cells/mm(2), P<0.001), anterior stromal keratocyte density (800±111 cells/mm(2) vs 555±115 cells/mm(2), P<0.001), posterior stromal keratocyte density (333±34 cells/mm(2) vs 270±47 cells/mm(2), P<0.001), endothelial cell density (2875±223 cells/mm(2) vs 2686±265 cells/mm(2), P<0.001), sub-basal nerve fiber density (31.2±8.4 nerves/mm(2) vs 18.1±9.2 nerves/mm(2), P<0.001), sub-basal nerve fiber length (21.4±3.4 mm/mm(2) vs 16.1±5.1 mm/mm(2), P<0.001), and sub-basal nerve branch density (median 50.0 (first quartile 31.2 - third quartile 68.7) nerve branches/mm(2) vs median 25.0 (first quartile 6.2 - third quartile 45.3) nerve branches/mm(2), P<0.001) were observed in patients with keratoconus. CONCLUSION: Significant microstructural abnormalities were identified in all corneal layers in the eyes of subjects with keratoconus using IVCM. This non-invasive in vivo technique provides an important means to define and follow progress of microstructural changes in patients with keratoconus.

Characteristics of the cornea in patients with pseudoexfoliation syndrome.

PURPOSE: To quantify the morphological alterations in corneal nerve fibers and cells in patients with pseudoexfoliation syndrome (PEX) and their relationship with the presence of hyperreflective endothelial deposits observed using in vivo confocal microscopy. METHODS: One eye each of 37 patients with PEX and 20 age-matched healthy control subjects was evaluated by in vivo corneal confocal microscopy. Patients with PEX were further classified into two groups: those with and without hyperreflective endothelial deposits. We evaluated the densities of basal epithelial cells, anterior and posterior stromal keratocytes, and endothelial cells and structure of sub-basal nerve fibers. RESULTS: The mean anterior and posterior stromal keratocyte and endothelial cell densities and corneal sub-basal nerve plexus variables were significantly lower in patients with PEX compared with those in healthy control subjects. The mean basal epithelial cell density did not significantly differ. CONCLUSION: Eyes with PEX presented decreased corneal sub-basal nerve plexus variables and cell densities in all corneas, except for the mean basal epithelial cell density. Further, a trend of lower corneal sub-basal nerve plexus measurements in patients with hyperreflective endothelial deposits compared with those without endothelial deposits was observed.

Intraocular lens explantation or exchange: indications, postoperative interventions, and outcomes.

PURPOSE: To analyze the indications for explantation or exchange of intraocular lenses (IOLs), which were originally implanted for the correction of aphakia during cataract extraction. METHODS: All cases that involved intraocular lens explantation or exchange in one institution between January 2008 and December 2014 were analyzed retrospectively. RESULTS: In total, 93 eyes of 93 patients were analyzed. The median time interval between implantation and explantation of the anterior chamber intraocular lenses (AC IOL) and posterior chamber intraocular lenses (PC IOL) was 83.40 ± 83.14 months (range: 1-276 months) and 55.14 ± 39.25 months (range: 1-168 months), respectively. Pseudophakic bullous keratopathy (17 eyes, 38.6%) and persistent iritis (12 eyes, 27.8%) in the AC IOL group and dislocation or decentration (30 eyes, 61.2%) and incorrect IOL power (nine eyes, 18.4%) in the PC IOL group were the most common indications for explantation of IOLs. The mean logMAR best corrected visual acuity (BCVA) improved significantly from 1.30 preoperatively to 0.62 postoperatively in the PC IOL group (p<0.001) but did not improve significantly in the AC IOL group (p=0.186). CONCLUSIONS: The primary indication for IOL explantation or exchange was pseudophakic bullous keratopathy in the AC IOL group and was dislocation or decentration in the PC IOL group. PC IOL explantation or exchange is safe and improves visual acuity.

Relationship of inferior oblique overaction to macular and subfoveal choroidal thickness.

PURPOSE: To evaluate the macular and subfoveal choroidal thickness of eyes with inferior oblique muscle overaction (IOOA) using enhanced depth imaging spectral domain optical coherence tomography (EDI SD-OCT). METHODS: The measurements of macular and subfoveal choroidal thickness obtained by EDI SD-OCT of patients with IOOA (24 patients) were compared with those of age- and sex-matched controls (25 subjects). RESULTS: There were no morphological abnormalities of the macula in patients with IOOA or in control subjects. There were no statistically significant differences in macular and subfoveal choroidal thickness between the eyes with IOOA and the eyes of the control subjects (P > 0.05). When the patients with IOOA were assigned to two distinct groups according to the degree of IOOA, the macular thickness did not differ between groups (P = 0.66), whereas subfoveal choroidal thickness measures were significantly lower in eyes with severe IOOA compared to eyes of the controls (P = 0.01). CONCLUSIONS: IOOA has no effect on the morphology and the thickness of the macula. Severe IOOA seems to be related to thinning of subfoveal choroid due to possible external mechanical effect.