Objectives: This study described the clinical profile of patients with keratoconus at a single tertiary referral hospital. Methods: This was a single-center, retrospective, cross-sectional study that reviewed medical records of patients diagnosed with keratoconus from January 2015 to August 2022. Data on the clinical profile, intervention, and clinical outcomes were collected from the chart review. Results: Forty (40) patients (79 eyes) were included in the study. Majority (98%) had bilateral disease in which 22 (55.5%) were affected asymmetrically. The mean age was 21 years. Most patients (72.5%) were male. Blurring of vision was the chief complaint in all patients. Atopy was present in 23 patients (57.5%). History of vigorous eye rubbing was present in 31 (77.5%). The mean interval from onset of symptoms to consult was 46.4 ± 33.38 months. The mean pinhole corrected distance visual acuity was 0.47 ± 0.41 (Snellen equivalent of 20/59). The average spherical equivalent was -7.48D ± 6.99D. Corneal protrusion on slit-lamp biomicroscopy was seen in 78 eyes (98.7%). Other findings included Fleischer ring (53.2%), Vogt's striae (19.0%), and apical corneal scar (24.0%). Only one eye (1.3%) had no corneal findings. Thirty-nine eyes (49.3%) were classified as advancedsevere keratoconus. Rigid contact lens was planned for 60 eyes (75.9%). Sixty-two eyes (78.5%) were for collagen cross-linking. Deep anterior lamellar keratoplasty was planned in 10 eyes (12.7%) and penetrating keratoplasty in two eyes (2.5%). Conclusion Keratoconus at the Philippine General Hospital was most frequently seen in young males and asymmetrically affects both eyes. Patients consulted relatively late and presented with a more advanced stage of the disease. History of ocular allergy and eye rubbing were significant risk factors. Improving awareness of this condition must be emphasized to detect keratoconus earlier.
Keratoconus ; Cornea ; Demography ; Philippines

OBJECTIVE: To prepare vitamin E polyethylene glycol 1000 succinate (TPGS)-modified insulin-loaded liposomes (T-LPs/INS) and evaluate its safety, corneal permeability, ocular surface retention and pharmacokinetics in rabbit eyes. METHODS: The safety of the preparation was investigated in human corneal endothelial cells (HCECs) using CCK8 assay and live/dead cell staining. In the ocular surface retention study, 6 rabbits were randomized into 2 equal groups for application of fluorescein sodium dilution or T-LPs/INS labeled with fluorescein in both eyes, which were photographed under cobalt blue light at different time points. In the cornea penetration test, another 6 rabbits divided into 2 groups for application of Nile red diluent or T-LPs/INS labeled with Nile red in both eyes, after which the corneas were harvested for microscopic observation. In the pharmacokinetic study, 2 groups of rabbits (n=24) were treated with eye drops of T-LPs/INS or insulin, and the aqueous humor and cornea were collected at different time points for measurement of insulin concentrations using enzyme linked immunosorbent assay. DAS2 software was used to analyze the pharmacokinetic parameters. RESULTS: The prepared T-LPs/INS showed good safety in cultured HCECs. Corneal permeability assay and fluorescence tracer ocular surface retention assay demonstrated a significantly higher corneal permeability of T-LPs/INS with a prolonged drug residence in the cornea. In the pharmacokinetic study, insulin concentrations in the cornea at 6, 15, 45, 60, and 120 min (P < 0.01) and in the aqueous humor at 15, 45, 60, and 120 min after dosing were significantly higher in T-LPs/INS group. The changes in insulin concentrations in the cornea and aqueous humor were consistent with a two-compartment model in T-LPs/INS group and with the one-compartment model in the insulin group. CONCLUSION The prepared T-LPs/INS shows an improved corneal permeability, ocular surface retention capacity and eye tissue concentration of insulin in rabbits.
Humans ; Animals ; Rabbits ; Insulin ; Liposomes ; Endothelial Cells ; Lipopolysaccharides ; Vitamin E ; Cornea ; Fluorescein

Objectives: Staphylococcal blepharitis is a common ocular condition that can cause significant visual morbidities due to corneal complications. This study described the clinical profile of patients with staphylococcal blepharitis seen in a tertiary referral eye center, and determined the frequency and the type of corneal complications, the possible reasons for the delay in diagnosis, and the management prior to the consult. Methods: This study was a single-center, five-year retrospective case series design. The charts of all patients from January 2016 to December 2021 with the diagnosis of staphylococcal blepharitis seen at the External Disease and Cornea Clinic of the Philippine General Hospital that have fulfilled the inclusion and exclusion criteria were included. The data extracted were age, sex, chief complaint, laterality, time of onset of symptoms to consult, previous consults, lid and lid margin findings, conjunctival and corneal findings, pre- and post-treatment uncorrected distance visual acuity, duration of follow-up, and treatments received. Results: Fifty-five (55) charts out of 107 charts with a diagnosis of staphylococcal blepharitis were included. Eighty percent (80%) or 44 patients had bilateral disease. Ninety-nine (99) eyes of 55 patients were analyzed. The median age of the study population was 19 years. Sixty-seven percent (67%) were female, and 33% were male. The mean duration of follow-up at the External Disease and Cornea Clinic was 10.8 ± 14.61 months. Corneal opacity, eye redness, and blurring of vision comprised 70% of the reasons for consult. The mean time from the onset of symptoms to consult was 18.36 ± 25.69 months. Sixty-seven percent (67%) had prior consults elsewhere and 45% came in with a different diagnosis. Seventy-eight (78) eyes had fibrin or crust on the lashes. Fifty percent (50%) of the eyes had concomitant conjunctivitis, while 30% had meibomitis. Fifty-eight percent (58%) of patients had corneal complications. Seventy-two percent (72%) of eyes had bilateral involvement. The median age of patients with corneal complications subgroup was 13 years. The most common corneal complications noted were neovascularization, phlyctenulosis, pannus formation, and marginal infiltrates or ulcers. Twenty-two percent (22%) of all study eyes had visually disabling corneal complications like corneal ulcer, descemetocele, corneal perforation, and corneal scar. Ninety percent (90%) of the patients received standard medical treatment and three patients underwent penetrating keratoplasty. The mean uncorrected distance visual acuity at initial consult of eyes with corneal complication was 20/55 (LogMAR 0.43 ± 0.51) and 20/35 (LogMAR 0.25 ± 0.40) after treatment (p = 0.032). Conclusion Staphylococcal blepharitis was most prevalent among young female patients, and it affected both eyes. Almost all patients manifested the typical lid margin lesions. Nearly 60% of the patients presented with corneal complications and 22% had corneal lesions that were potentially blinding. Close to 50% had delay in treatment due to misdiagnosis.
blepharitis ; staphylococcus ; cornea ; blindness

BACKGROUND: Corneal confocal microscopy (CCM) is a noninvasive technique to detect early nerve damage of diabetic sensorimotor polyneuropathy (DSPN). Time in range (TIR) is an emerging metric of glycemic control which was reported to be associated with diabetic complications. We sought to explore the relationship between TIR and corneal nerve parameters in asymptomatic patients with type 2 diabetes (T2DM). METHODS: In this cross-sectional study, 206 asymptomatic inpatients with T2DM were recruited. After 7 days of continuous glucose monitoring, the TIR was calculated as the percentage of time in the glucose range of 3.9 to 10.0 mmol/L. CCM was performed to determine corneal nerve fiber density, corneal nerve branch density, and corneal nerve fiber length (CNFL). Abnormal CNFL was defined as ≤15.30 mm/mm 2 . RESULTS: Abnormal CNFL was found in 30.6% (63/206) of asymptomatic subjects. Linear regression analyses revealed that TIR was positively correlated with CCM parameters both in the crude and adjusted models (all P   <  0.05). Each 10% increase in TIR was associated with a 28.2% (95% CI: 0.595-0.866, P  = 0.001) decreased risk of abnormal CNFL after adjusting for covariates. With the increase of TIR quartiles, corneal nerve fiber parameters increased significantly (all P for trend <0.01). The receiver operating characteristic curve indicated that the optimal cutoff point of TIR was 77.5% for predicting abnormal CNFL in asymptomatic patients. CONCLUSIONS There is a significant independent correlation between TIR and corneal nerve fiber loss in asymptomatic T2DM patients. TIR may be a useful surrogate marker for early diagnosis of DSPN.
Humans ; Diabetes Mellitus, Type 2/complications* ; Cross-Sectional Studies ; Blood Glucose Self-Monitoring ; Blood Glucose ; Nerve Fibers ; Diabetic Neuropathies ; Cornea ; Microscopy, Confocal/methods*

Blood Glucose Self-Monitoring ; Blood Glucose ; Cornea ; Microscopy, Confocal

Cornea ; Epithelium, Corneal ; Iontophoresis ; Riboflavin

Femtosecond laser small incision lenticule extraction (SMILE) with different residual stromal thicknesses (RST) is set to investigate its effect on corneal biomechanical properties of rabbits in vivo. In this study, 24 healthy adult Japanese rabbits were randomly divided into group A and B. The RST of group A was set 30% of the corneal central thickness (CCT), and the RST of group B was 50% of the CCT. The thickness of the corneal cap in both groups was set one third of CCT. Corneal visualization Scheimpflug technology (Corvis ST) and Pentacam three-dimensional anterior segment analyzer were used to determine corneal biomechanical and morphological parameters before surgery, and 1 week, 1 month and 3 months after surgery. Pearson correlation analysis was used to analyze factors affecting corneal biomechanical parameters after SMILE. The results showed that the corneal stiffness of group A was significantly higher than that of group B at 1 week and 1 month after surgery, and most biomechanical parameters returned to preoperative levels at 3 months postoperatively. The results of correlation analysis showed that postoperative CCT and RST were the main factors affecting corneal biomechanical parameters after SMILE. There was no significant difference in corneal posterior surface height (PE) between 3 months after surgery and before surgery in both two groups. It indicates that although the ability to resist deformation of cornea decreases in SMILE with thicker corneal cap and less RST, there is no tendency to keratoconus, which may be related to the preservation of more anterior stromal layer.
Animals ; Biomechanical Phenomena ; Cornea/surgery* ; Postoperative Period ; Rabbits

BACKGROUND: Normal tension glaucoma (NTG) is a less pressure-dependent type of glaucoma with characteristic optic neuropathy. Recently, the biomechanical mechanism has been thought to account for glaucomatous optic neuropathy to some degree. We intended to compare dynamic corneal response parameters (DCRs) among patients with primary open-angle glaucoma with normal tension or hypertension and controls. The correlations between DCRs and known risk factors for glaucoma were also analyzed. METHODS: In this cross-sectional study, 49 NTG subjects, 45 hypertension glaucoma (HTG) subjects, and 50 control subjects were enrolled. We compared the differences in DCRs using corneal visualization Scheimpflug technology among the NTG, HTG, and control groups. We also analyzed the correlations between DCRs and known risk factors for glaucoma (eg, central corneal thickness [CCT], intraocular pressure [IOP], etc). RESULTS: The maximum inverse concave radius (NTG: 0.18 [0.17, 0.20] mm-1; control: 0.17 [0.16, 0.18] mm-1; P = 0.033), deformation amplitude ratio of 2 mm (DAR 2 mm, NTG: 4.87 [4.33, 5.39]; control: 4.37 [4.07, 4.88]; P < 0.001), and DAR 1 mm (NTG: 1.62 [1.58, 1.65]; control: 1.58 [1.54, 1.61]; P < 0.001) were significantly higher in NTG than in the controls. The integrated radius (IR, NTG: 8.40 ± 1.07 mm-1; HTG: 7.64 ± 1.31 mm-1; P = 0.026) and DAR 2 mm (NTG: 4.87 [4.33, 5.39]; HTG: 4.44 [4.12, 5.02]; P < 0.007) were significantly higher, whereas the stiffness parameter at the first applanation (SP-A1, NTG: 91.23 [77.45, 107.45]; HTG: 102.36 [85.77, 125.12]; P = 0.007) was lower in NTG than in HTG. There were no significant differences in the DCRs between HTG and control groups (P > 0.05). In the univariate and multivariate analyses, some of the DCRs, such as IR, were negatively correlated with CCT and IOP, whereas SP-A1 was positively correlated with CCT and IOP. CONCLUSIONS The cornea was more deformable in NTG than in HTG or controls. There were no significant differences in corneal deformability between HTG and controls. The cornea was more deformable with the thinner cornea and lower IOP.
Biomechanical Phenomena ; Cornea ; Cross-Sectional Studies ; Glaucoma, Open-Angle ; Humans ; Hypertension ; Intraocular Pressure ; Low Tension Glaucoma

Diabetic peripheral neuropathy(DPN),a chronic diabetic microvascular complication with a high incidence among diabetic patients,increases the risk of diabetic foot and amputation.Many methods are available for screening and evaluating DPN,including traditional 10 g monofilament,tuning fork and vibration perception,and tendon reflex tests,which should be combined with some nerve function score systems to improve the detection rate and accuracy for DPN.In recent years,a number of noninvasive new techniques have been developed for the evaluation of nerve injury,such as corneal confocal microscopy,quantitative sensory testing,current perception threshold test,sympathetic sudomotor function evaluation,and quantitative detection of skin advanced glycation end products.This paper reviews these noninvasive methods for screening and evaluating DPN to help clinicians detect and focus on DPN early.
Cornea ; Diabetes Mellitus ; Diabetic Foot ; Diabetic Neuropathies/diagnosis* ; Humans ; Mass Screening ; Microscopy, Confocal

OBJECTIVES: To investigate angle Kappa and diopter distribution in myopic patients and the changes of angle Kappa and corneal morphology after Sub-Bowman-Keratomileusis (SBK), and to analyze the effects of the surgery on corneal morphologic changes and the patients' near fixation characteristics. METHODS: The clinical data of 134 myopic patients (268 eyes) undergoing SBK from August 2015 to August 2016 were retrospectively analyzed. Angle Kappa, corneal curvature in the central corneal region of 3 mm, and post-corneal Diff value were measured by Orbscan IIz Corneal Topography System before operation, 1 month and 6 months after operation. According to the values of angle Kappa before SBK, the patients were divided into 2 groups: the large K group (angle Kappa≥5°, 71 eyes) and the small K group (angle Kappa<5°, 197 eyes). Correlation analysis of the factors influencing angle Kappa at 6 months after operation was performed. RESULTS: In the large K group, angle Kappa was (5.67±0.65)°, spherical equivalent was (-4.84±2.32) D, and angle Kappa was decreased after operation (both CONCLUSIONS The angle Kappa is decreased in low-moderate myopia patients with large angle Kappa, while is increased in high myopia patients with small angle Kappa after SBK. Myopia patients after SBK will look for the new balance of the binocular accommodation and vergence function for improving the comfort in the near-work situations.
Cornea/surgery* ; Humans ; Keratomileusis, Laser In Situ ; Myopia/surgery* ; Refraction, Ocular ; Retrospective Studies