Repeatability and agreement of AOCT-1000 M, RTVue XR and IOL master 500 in measuring corneal thickness mapping and axial length applying principle of optical coherence tomography.

PURPOSE: To evaluate the repeatability and agreement of Fourier-domain optical coherence tomography (AOCT-1000 M and RTVue XR) and partial coherence interferometry biometer (IOL Master 500) in measuring corneal thickness mapping and axial length respectively. METHODS: Corneal thickness was measured by AOCT-1000 M and RTVue XR. Axial lengths were measured by AOCT-1000 M and IOL Master 500. The repeatability and agreement of corneal thickness and axial length were calculated in two groups of devices. The intraclass correlation coefficient (ICC) was used to verify the repeatability of the device. The 95% confidence interval of the difference compared to the set cut-off value was used to verify the agreement between the two devices. RESULTS: A total of 60 subjects with 58 eyes were included. The central corneal thickness measured by AOCT-1000 M and RTVue XR were 504.46 ± 42.53 µm and 504.43 ± 42.89 µm respectively. The average difference between groups was 0.03 ± 4.58 µm, and the 95% confidence interval was (-1.17, 1.24), which was far less than the set threshold value of 15 µm (P < 0.001). Both RTVue XR and AOCT-1000 M had very good ICC values of central corneal thickness (0.998 and 0.994, respectively). The average axial lengths measured by AOCT-1000 M and IOL Master 500 were 24.28 ± 1.25 mm and 24.29 ± 1.26 mm respectively and the 95% confidence interval was (-0.02, 0.01), which was less than the set threshold value of 0.15 mm (P < 0.001). The ICC for both devices were 1.000. CONCLUSION: Good repeatability and agreement were seen in measurements of central corneal thickness and axial length by AOCT-1000 M.

Is Orthokeratology Treatment Zone Decentration Effective and Safe in Controlling Myopic Progression?

OBJECTIVE: To compare the myopia control efficacy and safety of decentered versus centered positioning of orthokeratology. METHODS: This is a retrospective intrasubject study, including 46 children with myopia (25 boys, 21 girls; age 11.12±0.33 years) treated for 1 year with OK decentration in one eye (group D) and central location in the other (Group C). Axial length was measured before and at 6 months and 12 months after the initial lens wear, respectively. Corneal topography was measured at baseline and at 1-month after lens wear. The corneal topography obtained from the 1-month visit was used to quantify treatment zone decentration (TZD) for each subject. Cycloplegic refraction was required for all children before fitting the orthokeratology lenses. RESULTS: No differences were found between the groups in the biological ocular parameters ( P ≥0.05 for all). The axial elongation in group D and group C differed after 6 and 12 months ( P <0.001 for all). Similar corneal staining rates ( P =0.06) were noted during follow-up in groups D (n=20; 7.24%) and C (n=10; 3.62%), all of grade I. The uncorrected visual acuity (UCVA) in group D and C differed after 1, 6, and 12 months ( P =0.002, 0.010, 0.044), except 3 months ( P =0.146). Group D (n=32; 17.39%) was more likely to have glare or ghosting (chi-squared test, P <0.001) than group C (n=12; 6.52%) during follow-up visits. Axial elongation was significantly associated with baseline spherical equivalent (SE) in group C ( P =0.019). In group D, axial elongation was significantly associated with SE and TZD ( P <0.05 for all). CONCLUSIONS: This intrasubject study showed that when the UCVA was acceptable and there were no apparent complications, orthokeratology decentration may be beneficial in controlling the progression of myopia. Axial elongation became slower in children with a higher SE and a larger TZD, because TZD ranged from 0.5 mm to 1.5 mm.

Assessment of patient compliance in orthokeratology and analysis of influencing factors: a cross-sectional study.

BACKGROUND: Patient non-compliance, that is, failure to perform standard wear and care orthokeratology (ortho-k) lenses procedures, has been shown to be a major risk factor for contact lens-associated complications. Therefore, this study aimed to investigate the compliance with wear and care behaviors of ortho-k patients and analyze its influencing factors. METHODS: Patients who were successfully prescribed ortho-k lenses at the Eye Center of the Second Affiliated Hospital of Zhejiang University School of Medicine (ECSAHZU) were enrolled in the study. Patient compliance with wear and care behaviors was examined through a questionnaire. RESULTS: This study assessed 238 subjects. The subjects' ages ranged from 7 to 25 (mean ± SD, 11.3 ± 2.5) years. The compliance with wear and care behaviors was 19.7%, and the subjects' self-assessment compliance was 96.6%. The compliance rate of subjects wearing lenses for less than 1 year was higher than that of subjects wearing lenses for more than 1 year (p < 0.001). In the first year, the compliance rates of wearing experiences for less than 1 month, 1 month, 3 months, 6 months, and more than 6 months were 45, 29, 21.6, 20, and 27.6%, respectively, and there were no statistically significant differences in compliance among these periods (p = 0.314). No correlation was identified between compliance and age (r = - 0.061, p = 0.527) or sex (r = 0.114, p = 0. 751). There was no correlation between compliance and lens care operator (r = - 0.626, p = 0.151). CONCLUSIONS: The compliance of ortho-k patients was poor. After wearing ortho-k lenses for more than 1 year, compliance with wear and care behaviors declined. In clinical practice, measures should be taken to solve these problems and improve the safety of wearing ortho-k lenses.

The safety of orthokeratology in myopic children and analysis of related factors.

OBJECTIVE: To evaluate the safety of overnight orthokeratology (OK) wear and explore whether factors such as age, refraction and allergic conjunctivitis (AC) history were associated with corneal adverse events (AEs) incidence. METHODS: Medical records of consecutive patients who started OK for myopia correction and continued for more than one year were retrospectively reviewed. Clinical data including sex, baseline age, spherical equivalent refraction (SER), and related medical histories were retrieved. A total of 489 eyes from 260 patients (age: 8-15 years; SER: -1.00 to -6.00 D) were included. Corneal adverse events were the primary outcome. The generalized estimating equations model was used to evaluate the effects of sex, age, SER, and allergic conjunctivitis history on corneal AE incidence over the one-year period. RESULTS: A total of 111 eyes (22.7%) had corneal AE during the one-year follow-up (corneal staining [n = 106], corneal infiltration [n = 5]) and the incidence of significant AE was 6.9%. The corneal AE incidence was associated with age (OR = 0.874, 95%CI = 0.781-0.978, p = 0.019); SER (OR=0.632, 95%CI=0.531-0.754, p < 0.001); and AC (OR=1.706, 95%CI=1.017-2.860, p = 0.043). High refraction was the key risk factor for significant AE (OR=0.542, 95%CI=0.401-0.732, p < 0.001). CONCLUSIONS: Orthokeratology is a safe option for children with myopia. Younger age, higher myopia, and AC were risk factors for corneal AE in OK wearers. Whereas, only higher myopia was a risk factor for significant AE.

Kayser-Fleischer ring with keratoconus: a coincidence? A case report.

BACKGROUND: It is rare for hepatolenticular degeneration [Wilson's disease (WD)] to occur along with keratoconus (KC). In our report, a teenager was diagnosed with WD because of the discovery of Kayser-Fleischer (KF) ring in the cornea, and concomitant KC was found. CASE PRESENTATION: A 19-year-old male was diagnosed with KC due to a rapid decline in visual acuity within a short period of time. Ocular examination revealed the presence of ring-shaped, dense, brown sediment at the Descemet membrane of the bilateral limbus cornea, exhibiting characteristics similar to those of KF ring. Then, the patient was referred to the Department of Neurology and diagnosed with asymptomatic WD. During the next 5 years of follow-up, the patient has worn RGP lenses, routinely taken drugs that inhibit copper absorption and promote copper excretion, and maintained a low-copper diet. He has never exhibited obvious systemic symptoms associated with WD, such as neurological, mental, or hepatic dysfunction, and the color of the KF ring has grown obviously lighter. Moreover, the morphology of the cornea has stabilized. CONCLUSION: Only one report of WD combined with KC was found in the literature. So far, there is no evidence of a correlation between the occurrence of the two diseases. However, a low-copper diet and active copper-reducing therapy may have played a role in stabilizing the patient's condition in this case.

Is It Possible to Predict Progression of Childhood Myopia Using Short-Term Axial Change After Orthokeratology?

OBJECTIVES: To investigate changes in axial length in children undergoing orthokeratology (OK) and evaluate short-term axial change in predicting post-OK myopia progression. METHODS: In this retrospective study, the subjects included 70 myopic children aged 8 to 15 years wearing OK contact lenses for more than 3 years. Axial length changes at 0.5, 1, 2, and 3 years relative to the baseline were measured. Patients were evaluated for age, spherical equivalent refraction (SER), pupil size, and half-year axial change using repeated analysis of variance and multivariate linear regression analysis to predict half to 3 year-axial elongation (AE, seventh-36th month post-OK). RESULTS: The axial length grew significantly during the 3 years; the mean annual axial growth was 0.20±0.12 mm. The half-year axial change was 0.04±0.12 mm. The univariate linear analyses showed that half to 3-year AE was correlated with baseline age (r=-0.393, P<0.001) and half-year axial change (r=0.379, P=0.001), but not pupil diameter (P=0.692) or SER (P=0.673). In a multiple linear regression model, the half to 3-year AE was related with the baseline age (standardized ß=-0.312, P=0.007) and half-year axial change (standardized ß=0.293, P=0.01). The model was fair (adjusted R=0.21) and statistically significant (F=10.24, P<0.001). CONCLUSIONS: It is practical to predict long-term AE with half-year axial change for children with OK correction. Therefore, this may aid in fast and timely measures in children who are predicted to have rapid myopia progression.

Changes of corneal tomography in patients with congenital blepharoptosis.

The study aimed to evaluate the effect of drooped eyelid on corneal tomography in congenital blepharoptosis patients. Sixty-four patients with congenital blepharoptosis and 64 age- and sex- matched healthy subjects were included. According to the eyelid margin to corneal light reflex distance (MRD), eyes with congenital blepharoptosis were categorized as mild, moderate, or severe. The eyes were scanned using the rotating Scheimpflug camera. Increased topometric parameters were observed in moderate and severe blepharoptosis. Back corneal elevations at the thinnest point were significant higher for mild (P = 0.009), moderate (P < 0.001), and severe (P < 0.001) congenital blepharoptosis compared with controls. Maximum Ambrósio's relational thickness (ART) was decreased in eyes with severe blepharoptosis (P < 0.001). Fnal D values were significantly higher in moderate (P < 0.001) and severe blepharoptosis (P < 0.001) groups than that of controls. There were significant correlations between MRD and most corneal tomographic parameters. Our findings indicated there was a trend toward subclinical keratoconus-like changes in the corneas of congenital blepharoptosis, with the increase of ptosis severity.

[Conductive keratoplasty for presbyopia and two years follow-up].

OBJECTIVE: To investigate the effect of conductive keratoplasty (CK) for presbyopia and 2 years follow-up. METHODS: This study is prospective clinical trial. CK was performed on 34 patients for presbyopia, in which 26 hyperopic patients underwent binocular operations and 8 emmetropic patients underwent monocular operation. The following-up time was 24 months. RESULTS: At 24 months postoperatively, for the hyperopia group, binocular uncorrected near visual acuity (33 cm) (5-logMAR) (4.63 ± 0.12) was increased significantly (t = 9.237, P < 0.001) compared pre-operatively (4.06 ± 0.15); binocular uncorrected distance visual acuity (4.99 ± 0.02) was significantly increased (t = 6.718, P < 0.05) compared pre-operatively (4.82 ± 0.21); for the emmetropia group, binocular uncorrected near visual acuity (33 cm) (5-logMAR) (4.68 ± 0.16) was increased significantly (t = 10.413, P < 0.001) compared pre-operatively (4.13 ± 0.18); binocular uncorrected distance visual acuity was same as pre-operative one; compared pre-operatively (+0.97 ± 0.63D), manifest refractive spherical equivalent was decreased significantly (P < 0.001) to peak value (-1.21 ± 1.00) D at 1 week, and then regressed to a relative plateau (-0.40 ± 0.70) D at 24 months; the regressive rate was decreased from (+0.35 ± 0.44) D/month at 1 month postoperatively to (+0.01 ± 0.01) D/months at 24 months postoperatively. Contrast sensitivity and glare sensitivity, intraocular pressure, tear break-up time, endothelial cell count, central corneal thickness, stereopsis function and best corrected visual acuity were not significantly changed. CONCLUSIONS: For treatment of presbyopia, CK appeared to be safe, effective, refractive-predictable and controllable, and relatively stable at 24 months post-operatively. More long-time follow-up is necessary for further evaluation.

High glucose may decrease the innate immune through TLRs in cornea epithelium.

PURPOSE: The purpose of this study was to investigate the high potential of glucose in inhibiting the innate immune in cultured human cornea epithelial cells (HCEC) and try to determine whether the role of high glucose on the HCEC relate to toll-like receptor (TLR)2 and TLR4. METHODS: Cells were cultured for 3 days in 5 mmol/l (normal glucose). Then high glucose (25 mmol/l) was added along with normal glucose with daily changes in media for 24 h. The cells were also treated with mannitol as an osmotic control. The cellular abundance of the mRNAs for TLR2 and TLR4 was determined by real-time polymerase chain reaction analysis. The proteins of TLR2 and TLR4 were also compared by immunofluorescent staining and western blot. The release of interleukin 6 (IL-6) and IL-8 from cultured HCEC was measured using enzyme-linked immunosorbent assays (ELISA) in the presence and absence of specific blocking antibodies to TLR2 and TLR4. RESULTS: Incubation of HCEC with high glucose showed that the mRNA expression of TLR2 and TLR4 was markedly inhibited. Immunofluorescent staining and western blot analysis confirmed that the protein expression of TLR2 and TLR4 was downregulated in response to high glucose. The result of ELISA also showed that the release of IL-6 and IL-8 can be inhibited by high glucose, but these inhibitions were partly counteracted after pretreatment with anti-TLR2 and/or anti-TLR4 monoclonal antibody. The results also showed that the osmotic control did not affect the expression of TLR2, TLR4, and IL-6, 8. CONCLUSIONS: High glucose may decrease the innate immune through TLRs in cornea epithelium.

[Advances in surgical management of presbyopia].

Presbyopia is age-related reduction in amplitude of accommodation and can not read comfortably. Current methods such as single-focus glasses, bifocal glasses and progressive additional lens are the most widely used for correction of presbyopia. All surgical solutions for presbyopia do not improve the physiological amplitude of accommodation. This article is an attempt to review the advances in surgical management of presbyopia.

[A preliminary study on development of human visual system in fetus by DiI-tracing].

OBJECTIVE: To reveal the morphological features and dynamic processes of the development of inter-connections in the retina, lateral geniculate nucleus (LGN), superior colliculus (SC) and visual cortex (VC) in human fetal life by using a fluorescent tracer, 1, 1'-dioctadecyl-3, 3, 3', 3'-tetramethylin-docarbocyanine perchlorate (DiI). METHODS: DiI was embedded into the optic tract, brachium of superior colliculus and subplate of visual cortex in fixed postmortem human tissues of 7 fetuses. The tissue was incubated at 37 degrees C for 4 to 10 weeks (ws). After DiI had satisfactorily diffused via axons of the visual system, the tissue was sectioned, mounted and observed under a confocal laser scanning microscope. RESULTS: In 12 week-fetus, retinogeniculate axon has already reached LGN, but there was no cellular lamination. After embedment, axons from retina arrived at SC, and the fibers were distributed along the dorsal part of the SC. At 12 and 22 ws, there were subplates under visual cortex. CONCLUSION: The retinogeniculate axon reaches LGN before 12 ws and forms cellular lamination after 12 ws. The axon from retina reaches SC before 12 ws. The subplate under visual cortex forms before 12 ws and disappears after 22 ws. DiI can be easily and effectively used to label the axon of visual system of human fetus to study the prenatal development of human visual pathway.