Taiwan Journal of Ophthalmology最新文献

Wide field retinal imaging has emerged as a transformative technology over the last few decades, revolutionizing our ability to visualize the intricate landscape of the retina. By capturing expansive retinal areas, these techniques offer a panoramic view going beyond traditional imaging methods. In this review, we explore the significance of retinal imaging-based biomarkers to help diagnose ocular and systemic conditions. We discuss quantitative biomarkers, including ischemic index, nonperfusion area and more, and their application in diabetic retinopathy, central retinal vein occlusion, neurodegenerative diseases, and more. In addition, we outline qualitative biomarkers such as choroidal venous hyperpermeability and intervortex anastomoses. The role of wide field fundus autofluorescence in assessing hereditary retinal diseases is also emphasized. Standardized imaging procedures, professional collaboration, and validation across a range of clinical circumstances are necessary for the effective use of these biomarkers. They have the potential to transform disease identification, risk assessment, and customize therapy.

This review explores recent technological advances in intraoperative imaging during retinal disease surgeries, focusing on their applicability in clinical practice and impact on surgical outcomes. A literature search identified studies discussing new imaging technologies, their advantages over conventional methods, relevant case studies, and literature reviews. Exclusion criteria included studies unrelated to retinal diseases, imaging technologies not suitable for intraoperative use, outdated articles, and nonscientific reports. Significant advancements, particularly with optical coherence tomography (OCT), have transformed retinal surgery by providing high-resolution images and real-time feedback, enhancing surgical precision and patient safety. However, the high costs of these technologies remain a barrier to widespread adoption, despite their potential to set new standards in ophthalmic surgery.

Intraoperative optical coherence tomography (iOCT) has been applied and studied in a variety of vitreoretinal surgeries for its feasibility, safety, and outcomes for years. Common scenarios include membrane peeling procedures, retinal detachments, choroidal-retinal biopsies, Argus implants, and subretinal injections. iOCT offers the surgeon a better understanding of the retinal microarchitectural changes and timely intraoperative feedback, directing a future view of precision surgery. However, this technology has not been widely adopted due to its limitations including cost, surgeons' habits, lack of compatible equipment, software limitations, and so on. We aim to highlight the importance of iOCT in guiding clinical-relevant surgical decisions by illustrating two vitreoretinal cases that are complex and less frequently encountered.

Inherited retinal degeneration (IRD) is a heterogeneous group of genetic disorders of variable onset and severity, with vision loss being a common endpoint in most cases. More than 50 distinct IRD phenotypes and over 280 causative genes have been described. Establishing a clinical phenotype for patients with IRD is particularly challenging due to clinical variability even among patients with similar genotypes. Clinical phenotyping provides a foundation for understanding disease progression and informing subsequent genetic investigations. Establishing a clear clinical phenotype for IRD cases is required to corroborate the data obtained from exome and genome sequencing, which often yields numerous variants in genes associated with IRD. In the current work, we review the use of contemporary retinal imaging modalities, including ultra-widefield and autofluorescence imaging, optical coherence tomography, and multispectral imaging, in the diagnosis of IRD.

The aim of this study is to describe genotype and phenotype of patients with bestrophinopathy. The case records were reviewed retrospectively, findings of multimodal imaging such as color fundus photograph, optical coherence tomography (OCT), fundus autofluorescence, electrophysiological, and genetic tests were noted. Twelve eyes of six patients from distinct Indian families with molecular diagnosis were enrolled. Exon 4 of BEST1 was mutated in 3 cases, while exons 2, 3, and 7 in others. Deletion is seen in Exon 7 and missense mutation in other exons. Sporadic autosomal dominant and recessive inheritance was observed in these families. Two patients had primary angle closure glaucoma with a history of consanguineous marriage and glaucoma in the family. Based on our findings, multifocal vitelliform subretinal deposits were the most common fundus finding in patients with autosomal recessive mutation while macular vitelliform lesion was seen with sporadic or autosomal dominant mutation; however, cosegregation analysis was not done. Baseline OCT showed macular and extramacular subretinal exudates, subretinal fluid, intraretinal cystic and schitic spaces, and thickened photoreceptors outer segment tips. Two patients developed abnormal vasculature and focal choroidal excavation in OCT. A severe reduction in the electro-oculogram Ardens ratio was noted while electroretinography was normal. Bestrophinopathy has a varied presentation with complex genotype-phenotype relationships. OCT is a noninvasive tool for monitoring and prognostication. Genetic testing of other family members should be facilitated.

Purpose: The present study aimed to assess the impact of diabetes mellitus and smoking in orbital vessels, utilizing resistive index (RI) through color Doppler imaging (CDI).

Materials and methods: The cross-sectional study consisted of 90 participants divided into three groups of 30 each. Group A consisted of normal individuals, Group B consisted of patients with diabetes, and Group C consisted of patients with a history of diabetes and smoking. The RIs were obtained for the orbital vessels for both eyes using CDI. Analysis of variance with post hoc Tukey's HSD test was conducted for pairwise comparison of the groups. Pearson's correlation test was used to correlate between RI and the amount of smoking.

Results: Significant differences were observed in the mean RI values of the ophthalmic artery, central retinal artery (CRA), and central retinal vein (CRV) in all three groups bilaterally (P < 0.001). Compared with patients in Group A, those in Group B had significantly larger RIs for all orbital vessels in both eyes (P < 0.01 for all). Patients in Group C had significantly larger RI for all three vessels (P < 0.001 for all) except for the CRV in the right eye than those in Group A. Compared with patients in Group B, those in Group C had significantly larger RI in CRA bilaterally (P = 0.05 for the right eyes and P = 0.024 for the left eyes). In Group C, a positive correlation was observed between RIs of all orbital vessels and the amount of smoking.

Conclusion: RIs of the orbital vessels are significantly increased in patients with diabetes and higher in diabetic smokers, suggesting that diabetes affects the retinal vasculature, and smoking exacerbates this pathology.

Recent advances of artificial intelligence (AI) in retinal imaging found its application in two major categories: discriminative and generative AI. For discriminative tasks, conventional convolutional neural networks (CNNs) are still major AI techniques. Vision transformers (ViT), inspired by the transformer architecture in natural language processing, has emerged as useful techniques for discriminating retinal images. ViT can attain excellent results when pretrained at sufficient scale and transferred to specific tasks with fewer images, compared to conventional CNN. Many studies found better performance of ViT, compared to CNN, for common tasks such as diabetic retinopathy screening on color fundus photographs (CFP) and segmentation of retinal fluid on optical coherence tomography (OCT) images. Generative Adversarial Network (GAN) is the main AI technique in generative AI in retinal imaging. Novel images generated by GAN can be applied for training AI models in imbalanced or inadequate datasets. Foundation models are also recent advances in retinal imaging. They are pretrained with huge datasets, such as millions of CFP and OCT images and fine-tuned for downstream tasks with much smaller datasets. A foundation model, RETFound, which was self-supervised and found to discriminate many eye and systemic diseases better than supervised models. Large language models are foundation models that may be applied for text-related tasks, like reports of retinal angiography. Whereas AI technology moves forward fast, real-world use of AI models moves slowly, making the gap between development and deployment even wider. Strong evidence showing AI models can prevent visual loss may be required to close this gap.

This study investigates the occurrence of multiple parafoveal retinal detachments (RDs) in myopic traction maculopathy (MTM), emphasizing the atypical extrafoveal involvement compared to central foveal detachment commonly observed. Patient 1, a 46-year-old male, exhibited MTM with retinoschisis and four small subretinal fluid (SRF) pockets inferior to the fovea, accompanied by a hyperautofluorescent vitelliform deposit. Patient 2, a 43-year-old male, reported ring-shaped dim vision in the left eye, displaying MTM with six stable SRF pockets surrounding the fovea. These SRF pockets maintained a stable size ranging from 173 to 1140 um in diameter over the course of a 5-year follow-up period. Interestingly, fluorescein and indocyanine angiography showed no leakage or hyperpermeability in both cases. The study highlights the necessity for a comprehensive exploration of extrafoveal RDs in MTM, challenging conventional expectations. The mechanism of these persistent extrafoveal detachments associated with myopic schisis was unknown. The findings prompt further research to unravel the intricate mechanisms of this rarely reported phenomenon, emphasizing the importance of expanding our understanding of extrafoveal manifestations in eyes with MTM.

Purpose: This study aimed to evaluate serum cystatin C as a potential biomarker for diabetic retinopathy (DR) in a rural Indian population, addressing the urgent need for effective screening tools amidst rising diabetes prevalence.

Materials and methods: A cross-sectional study recruited 112 patients with diabetes mellitus from Sambalpur, Odisha, India, categorized into groups with and without DR. Serum cystatin C levels were measured alongside clinical and demographic parameters, using established diagnostic methods.

Results: Patients with DR exhibited significantly higher serum cystatin C levels compared to those without DR (mean: 0.99 ± 0.50 mg/L vs. 0.80 ± 0.36 mg/L, P = 0.027). Adjusted analysis showed a notable association between higher cystatin C tertiles and DR (adjusted odd's ratio: 7.65, 95% confidence interval: 1.49-39.08, P = 0.01), highlighting its potential as an independent predictor.

Conclusion: Elevated serum cystatin C levels were strongly associated with the presence of DR, suggesting its utility as a biomarker for early identification and risk stratification in diabetic patients. Integration of cystatin C measurement into routine clinical practice may enhance DR screening and management strategies, offering potential benefits in reducing vision loss and improving patient outcomes. This study underscores the need for further longitudinal research to validate these findings and elucidate the temporal relationship between cystatin C levels and DR progression.