International journal of ophthalmology最新文献

[This corrects the article DOI: 10.18240/ijo.2024.08.14.].

Aim: To evaluate the visual outcomes of standard amblyopic treatment add-on training via perceptual learning in refractive amblyopic children and to identify the risk factors for treatment failure.

Methods: Retrospective charts were reviewed in children with refractive amblyopia who received standard treatment and add-on Cambridge Visual Stimulator (CAM) training. The add-on CAM group that was enrolled had worn full-corrected glasses for at least 2mo before training. A control group received only the standard treatment. Treatment success was defined as best-corrected visual acuity (BCVA) ≥20/25. The age, sex, initial BCVA, refractive errors, sessions and duration of training, and final BCVA were recorded.

Results: A total of 209 children (129 children in add-on CAM group and 80 children in control group) were enrolled. Seventy-six percent of unilateral and 87% of bilateral amblyopic children achieved treatment success. In children with unilateral or bilateral moderate amblyopia, the duration to reach BCVA ≥20/25 was significantly shorter in add-on CAM group than in control group. Poor initial BCVA (P<0.001) and high astigmatism (P=0.007) were risk factors for treatment failure after add-on CAM training. Age, sex, and types of refractive error were not associated with treatment success.

Conclusion: Add-on CAM training is an effective strategy for visual improvement and can shorten the treatment course when the effect of standard treatment is limited in amblyopic children.

Aim: To investigate tomographic features of late corneal ectasia after keratoplasty for keratoconus and compare penetrating keratoplasty (PK) and deep anterior lamellar keratoplasty (DALK) in terms of incidence, time of onset and risk factors of corneal ectasia.

Methods: Sixty eyes with PK and 30 eyes with DALK operated between 1999 and 2021 were analyzed. Final Pentacam scans were evaluated together with vision and previous topographies. Main outcome measures were vision, K values, apparent thinning on graft-host cornea and the difference between opposing quadrants in the thinnest point measurements. Anterior segment optic coherence tomography was performed for further evaluation.

Results: Mean follow-up was 127.2mo (24-282mo) in PK, and 64.3mo (24-144mo) in DALK. K max was higher in DALK (60.6 vs 56.7 D, P=0.012). Inferior recipient was thinner (595.9 µm) in PK than DALK (662.2 µm, P=0.021), due to longer follow-up. Overall corneal ectasia rate was 20.0% within 24y. Ectasia rate was the same (6.7%) in DALK 2/30 and in PK 4/60 in 10y and 13.3% in 12y (4/30 and 8/60, respectively). It increased to 23.3% (14/60) in PK over 24y. While ectasia was not seen before 7y in PK, it could be seen in DALK starting from the 5^th year. The intervals between keratoplasty and ectasia were 144.5mo in PK and 99mo in DALK. Inferior recipient was significantly thinner in 18 eyes with ectasia (502.7 µm) compared to 76 non-ectasia (649.1 µm, P=0.000). Inferior graft was thinner (561.0 vs 620.4 µm, P=0.006), K max (63.3 vs 56.5 D, P=0.000), and anterior elevation was higher in ectasia (89.1 vs 48.6 µm, P=0.002). Accelerated crosslinking was performed on 5 eyes.

Conclusion: Inferior-superior recipient and inferior graft thinning on tomography, with high K max and anterior elevation emerge as the most reliable criteria for the diagnosis of late ectasia. The incidence of corneal ectasia increases with the time.

Aim: To describe the distribution of ocular biometrics and to evaluate its associations with refractive error and to assess the contribution from ocular parameters to refractive error among Chinese myopic children.

Methods: This cross-sectional study evaluated subjects aged 8-12y. Keratometry, ocular biometry, and cycloplegic autorefraction were performed on each subject. Spherical equivalent refraction (SER) and ocular biometrics were assessed as a function of age and gender. The Pearson correlation analysis between SER and ocular biometrics was carried out. Multiple linear regression was performed to analyze the association between SER and ocular parameters.

Results: A total of 689 out of 735 participants (321 boys, 48.1%) were analyzed, with a mean SER of -2.98±1.47 diopter (D). Axial length (AL), anterior chamber depth (ACD), corneal radius of curvature (CR), horizontal visible iris diameter (HVID), central corneal thickness (CCT) and lens power (LP) showed normal distribution. The AL, AL/CR ratio, ACD and CR increased from 8 to 12y of age, while SER and LP decreased, HVID and CCT remained stable. There was no difference in gender. SER decreased by 0.929 D for every 1 mm increase in AL and decreased by 1.144 D for every 0.1 increase in AL/CR ratio. The Pearson correlation coefficient between SER and AL was -0.538 (P<0.01) and -0.747 (P<0.01) between SER and AL/CR ratio. For the SER variance, AL explained 29.0%, AL/CR ratio explained 55.7%, while AL, CR, ACD and LP explained 99.3% after adjusting for age and gender.

Conclusion: The AL, CR, ACD and LP are the most important determinants of myopic refractive error during myopia progression.

Aim: To compare the exposure rate, infection rate, percentage of enhancement, and success rate between Medpor and the three-dimensional printed polyethylene (3DP-PE) orbital implant in a preliminary report.

Methods: This prospective, randomized, equivalence, controlled trial was conducted at two institutes. The equivalent margin was ±10%. The sample size for the equivalence trial was 174 participants per group. Patients who were eligible for enucleations received either Medpor or 3DP-PE implants based on a randomized block of six. The surgeries were performed by five oculoplastic surgeons. The assessor and patients were masked. The magnetic resonance imaging (MRI) of the orbit was performed at least 6mo after operation and the fibrovascular ingrowth was analyzed using the Image J software. Follow-up continued at least 1y after surgery. The intention to treat and per protocol approaches were used.

Results: Totally 128 patients met the criteria in the report. Fifty Medpor and 55 3DP-PE cases completed the trial. The most common cause of blindness was trauma. The mean follow-up times of Medpor and 3DP-PE were 33 and 40mo respectively. The exposure rate was not statistically significant between two groups (6.0% and 7.3%), P<0.05, 95%CI (-9.8%, +12.0%). The success rates were 94% (Medpor) and 92.7% (3DP-PE). No postoperative infection was reported. Nine patients had MRI tests and two had implant exposures with 66.3% enhancement at 75mo (Medpor) and 58% enhancement at 57mo (3DP-PE) postoperatively.

Conclusion: There is no statistically significant difference in exposure rate and success rate between Medpor and 3DP-PE in enucleation in the report. However, we cannot conclude that they are equivalent in terms of the exposure rate and success rate because the 95%CI is wider than ±10%. The infection rate is equivalent in both groups.

Aim: To investigate the effect of using base-out prisms on nystagmus, visual acuity and contrast sensitivity in patients with albinism.

Methods: In this interventional study, patients with albinism who had nystagmus were enrolled. A comprehensive eye exam was conducted, which included refraction, assessment of far and near vision acuity, and contrast sensitivity measurements. To check for the nystagmus, a videonystagmography was used. The tests were carried out in three modes: without any correction, with optical correction, and with correction using base-out prisms in three different powers, including 4, 6, and 8 prism diopters.

Results: Totally 23 patients with average age of 28.65±12.13 were examined. It was found that the use of optical correction and optical correction with prisms resulted in a statistically significant improvement in both far (at least: P<0.006) and near visual acuity (at least: P<0.001 except for prism 8; P<0.02). In addition, contrast sensitivity significantly improved at all low and medium frequencies except for correction with prism 8 in frequency 1.5 (at least: P<0.01 except for prism 4, frequency 6; P=0.04). no significant improvement was observed in the evaluation of nystagmus characteristics.

Conclusion: Optical correction with a prism can improve visual acuity and some spatial frequencies, but failed to improve nystagmus parameters.

Aim: To investigate the molecular mechanisms underlying the influence of hypoxia and alpha-ketoglutaric acid (α-KG) on scleral collagen expression.

Methods: Meta-analysis and clinical statistics were used to prove the changes in choroidal thickness (ChT) during myopia. The establishment of a hypoxic myopia model (HYP) for rabbit scleral fibroblasts through hypoxic culture and the effects of hypoxia and α-KG on collagen expression were demonstrated by Sirius red staining. Transcriptome analysis was used to verify the genes and pathways that hypoxia and α-KG affect collagen expression. Finally, real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR) was used for reverse verification.

Results: Meta-analysis results aligned with clinical statistics, revealing a thinning of ChT, leading to scleral hypoxia. Sirius red staining indicated lower collagen expression in the HYP group and higher collagen expression in the HYP+α-KG group, showed that hypoxia reduced collagen expression in scleral fibroblasts, while α-KG can elevated collagen expression under HYP conditions. Transcriptome analysis unveiled the related genes and signaling pathways of hypoxia and α-KG affect scleral collagen expression and the results were verified by RT-qPCR.

Conclusion: The potential molecular mechanisms through which hypoxia and α-KG influencing myopia is unraveled and three novel genes TLCD4, TBC1D4, and EPHX3 are identified. These findings provide a new perspective on the prevention and treatment of myopia via regulating collagen expression.

Dry eye, the most common ocular surface disease, can cause ocular surface tissue damage and discomfort symptoms and seriously affect people's quality of life. The etiology of dry eye is diverse, and its pathogenesis is complex. The oxidative stress reaction is considered to be among the important factors in the pathogenesis of dry eye. Therefore, activating the antioxidant system has a potential therapeutic effect on dry eye. Nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway is considered the most important antioxidant pathway in the body. The activation of the Nrf2 signaling pathway and its interaction with other pathways are important mechanisms to prevent the occurrence and development of dry eye. This review describes the structure and function of Nrf2, summarizes the changes in the oxidative stress response in dry eye, focuses on the potential mechanism of the Nrf2 signaling pathway in the treatment of dry eye, and, finally, summarizes the drugs that activate the Nrf2 signaling pathway in the treatment of dry eye.

Aim: To develop an automated model for subfoveal choroidal thickness (SFCT) detection in optical coherence tomography (OCT) images, addressing manual fovea location and choroidal contour challenges.

Methods: Two procedures were proposed: defining the fovea and segmenting the choroid. Fovea localization from B-scan OCT image sequence with three-dimensional reconstruction (LocBscan-3D) predicted fovea location using central foveal depression features, and fovea localization from two-dimensional en-face OCT (LocEN-2D) used a mask region-based convolutional neural network (Mask R-CNN) model for optic disc detection, and determined the fovea location based on optic disc relative position. Choroid segmentation also employed Mask R-CNN.

Results: For 53 eyes in 28 healthy subjects, LocBscan-3D's mean difference between manual and predicted fovea locations was 170.0 µm, LocEN-2D yielded 675.9 µm. LocEN-2D performed better in non-high myopia group (P=0.02). SFCT measurements from Mask R-CNN aligned with manual values.

Conclusion: Our models accurately predict SFCT in OCT images. LocBscan-3D excels in precise fovea localization even with high myopia. LocEN-2D shows high detection rates but lower accuracy especially in the high myopia group. Combining both models offers a robust SFCT assessment approach, promising efficiency and accuracy for large-scale studies and clinical use.