Ocular side effects of systemic medications

Background: Systemic medications, which are crucial for managing a wide range of diseases from hypertension and diabetes to infections and cancers, can induce substantial ocular side effects. These effects impact visual function and quality of life, necessitating awareness and monitoring by healthcare professionals. The current review summarizes the range and mechanisms of these ocular toxicities. Methods: This narrative review was derived from a targeted literature search using major electronic databases including PubMed/MEDLINE, Embase, Scopus, and Google Scholar. Keywords related to ocular side effects of systemic medications were utilized to identify relevant studies published from January 1, 2000, to December 30, 2024. The included articles pertained to ocular manifestations of systemic drug use, their mechanisms of toxicity, and associated management strategies. Results: This study identified notable ocular side effects related to various systemic medications. Amiodarone was consistently linked to corneal deposits and colored halos, prompting recommendations for regular eye examinations. Isotretinoin was frequently associated with dry mucous membranes and blepharoconjunctivitis. Chloroquine and hydroxychloroquine were found to cause corneal changes and irreversible retinal damage with prolonged use. Studies of allopurinol presented conflicting evidence regarding its relationship with cataract risk. Corticosteroid use was associated with cataract formation and potential elevation of intraocular pressure. Ethambutol has been identified as a potential cause of optic neuritis. Topiramate was linked to acute angle-closure glaucoma, particularly early in treatment. Anticholinergic drugs can impact various parts of the eye. They cause ciliary muscle relaxation, leading to temporary blurred vision. This loss of accommodation, also known as “iatrogenic presbyopia,” results from paralysis of the ciliary muscle. Phosphodiesterase type 5 inhibitors, such as sildenafil, may cause pupil dilation, redness, dryness, blurred vision, and temporary cyanopsia. Additionally, patients taking vigabatrin may experience progressive constriction of the visual fields, necessitating regular visual field assessments. Epidemiological studies indicate that approximately 15% of patients taking systemic medications experience dry eye syndrome. These findings underscore the diverse range and impact of drug-induced ocular toxicities. However, vigilant monitoring and prompt management can help mitigate vision-threatening complications and preserve patients’ visual health. Addressing these ocular side effects requires strong interdisciplinary communication among ophthalmologists, optometrists, primary care physicians, and other specialists. Conclusions: The wide range of ocular manifestations of systemic medication use emphasizes the importance of monitoring patients for these side effects. Collaborative management by eye care professionals and prescribing physicians is vital to mitigate risks. Further research must focus on the mechanisms of drug-induced ocular toxicity and developing effective preventive measures

Ethical integrity in systematic reviews and meta-analyses: challenges, pitfalls, and best practices in ophthalmology

Background: Systematic reviews and meta-analyses (SRMAs) are central to evidence-based ophthalmology, influencing clinical guidelines and treatment decisions. However, the rapid increase in SRMA publications has exposed serious ethical concerns, including selective reporting, duplicate publication, plagiarism, authorship misconduct, and undeclared conflicts of interest. Despite established frameworks such as Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA), International Prospective Register of Systematic Reviews (PROSPERO), and International Committee of Medical Journal Editors (ICMJE), ethical compliance remains inconsistent, undermining the credibility of synthesized evidence. We aimed to examine the ethical landscape of SRMAs with a particular focus on ophthalmology, highlighting common pitfalls, evaluating current guidelines, and providing practical recommendations to ensure that these reviews are conducted and reported with the highest ethical standards—ultimately safeguarding the integrity of the evidence base that underpins clinical eye care. Methods: A structured literature search was conducted in PubMed, Scopus, Web of Science, and Google Scholar through May 2025 using combinations of the terms “systematic review,” “meta-analysis,” “ethics,” “research integrity,” and “ophthalmology.” Relevant guidelines, peer-reviewed studies, and editorials were synthesized to identify ethical pitfalls and propose best practice solutions. Results: We illustrate these challenges with ophthalmology-specific examples and highlight the downstream impact of unethical SRMAs on clinical practice and public trust. We also propose actionable recommendations for researchers, editors, and institutions to enhance the ethical quality of SRMAs, including improved training in research integrity, stricter enforcement of reporting guidelines, and increased editorial oversight. By addressing these ethical dimensions, the ophthalmic community can ensure that SRMAs not only meet methodological benchmarks but also reflect the core values of scientific honesty, accountability, and patient-centeredness. Approximately one-third of ophthalmology SRMAs fail to assess bias or comply with PRISMA guidelines. Industry-sponsored reviews have shown a tendency to favor commercially linked interventions, raising objectivity concerns. Key ethical concerns include: lack of protocol registration, selective inclusion of studies, inclusion of retracted or flawed trials, duplicate or plagiarized data, and authorship and disclosure misconduct. Conclusions: To protect the integrity of ophthalmic evidence synthesis, SRMAs must adhere to the highest ethical standards. Researchers should commit to transparent, methodologically rigorous, and ethically sound practices. Journals and institutions must enforce compliance, provide oversight, and support education in research integrity. Field-specific adaptations of reporting standards may further support ethical clarity. Ultimately, ethical SRMAs are critical to preserving trust, guiding responsible care, and fulfill their intended role as trustworthy instruments in advancing evidence-based ophthalmology

Treatment options for diabetic retinopathy in pregnancy

Letter to the Edito

Intracorneal ring segment implantation for eyes with keratoconus and corneas thinner than 400 microns

Background: Intracorneal ring segment (ICRS) implantation is a promising and effective treatment option for keratoconus. However, a corneal thickness of less than 400 microns presents a unique challenge. This study assessed the clinical course and visual outcomes in patients with Amsler–Krumeich stage 2 or greater keratoconus and clear corneas, with a minimal corneal stromal thickness of 350 microns but less than 400 microns in the proposed implantation area, up to 6 months after ICRS implantation. Methods: This non-randomized, prospective, interventional case series was conducted at a single tertiary center, consecutively recruiting patients with keratoconus scheduled for ICRS implantation who fulfilled the eligibility criteria. Detailed ophthalmological assessments were performed at baseline and 6 months postoperatively, including measurements of uncorrected distance visual acuity (UCDVA), best corrected distance visual acuity (BCDVA), and manifest refraction with documentation of the spherical component of the refractive error (in diopters [D]), cylindrical component of refractive error (in diopter cylinder [DC]), and axis of astigmatism (in degrees). Corneal topographic and pachymetric evaluations were performed using Pentacam HR, including keratometry (K) values in D (flat K or K1, steep K or K2, and mean K or Km), corneal astigmatism in DC, central corneal thickness (CCT), and corneal asphericity coefficient (Q value). Results: We included nine eyes of nine patients with keratoconus and a mean (standard deviation) age of 33.2 (8.2) years (range: 25–44 years). Five patients were women (56%), and four were men (44%). All eyes experienced a statistically significant improvement in the mean visual and refractive outcomes at the 6-month postoperative visit, including UCDVA, BCDVA, sphere, and cylinder (all P < 0.05). Similarly, we recorded a statistically significant improvement in the mean corneal tomographic and topographic data, including the K1, K2, Km, CCT, and Q values (all P < 0.05). No serious complications occurred for up to 6 months of follow-up. Only one patient complained of night glare, which was successfully treated with pilocarpine 1% eyedrops for 3 months. Conclusions: ICRS implantation may offer a safe and effective option for selected patients with keratoconus and corneal thickness less than 400 microns, as evidenced by short-term improvements in visual, refractive, topographic, and tomographic parameters. No vision-threatening complications occurred. However, given the case-series study design, limited sample size, and short follow-up period, these findings should be interpreted with caution. Further controlled trials are required to validate these preliminary results. &nbsp

Optic nerve sheath diameter as a surrogate for intracranial pressure: a noninvasive follow-up strategy using ocular ultrasonography

Background: Idiopathic intracranial hypertension (IIH), characterized by increased intracranial pressure (ICP) without a clear cause, typically affects obese women of reproductive age. Although lumbar puncture (LP) is diagnostic, its invasiveness limits its repeated use. Consequently, a non-invasive alternative is essential. Therefore, we assessed whether optic nerve sheath diameter (ONSD) measurement via orbital ultrasonography could serve as an alternative method for monitoring changes in ICP in patients with IIH. Methods: In this prospective observational study, patients with IIH, diagnosed using the modified Dandy criteria, underwent ONSD assessment using B-scan ultrasonography. Bilateral measurements were performed 3 mm posterior to the optic disc with the probe and sterile gel placed on the closed upper eyelid. ONSD was recorded before LP and one month after initiation of medical treatment. Comprehensive ophthalmologic examinations were also conducted. Patients with ocular pathology, neuroimaging abnormalities, or contraindications to LP were excluded. Results: Twenty-four eyes from 12 female patients with IIH were evaluated. The mean (standard deviation [SD]) age was 27.3 (6.9) years, and the mean ICP was 34.8 (10.3) cm H2O. Although the ONSD decreased one month after LP, changes in mean ONSD of the right eye, left eye, and their average were not statistically significant (all P > 0.05). No significant correlations were observed between baseline ICP and ONSD values (all P > 0.05). Conclusion: Although ONSD measurement via ultrasonography provides a noninvasive method for assessing ICP in IIH, our findings revealed no significant change one month after treatment initiation. ONSD may gradually decrease following LP; however, a return to baseline values appears to require a prolonged period, even after ICP normalization. This should be considered during patient follow-up. Our findings underscore the limitations of using ONSD as a standalone marker for monitoring therapeutic response. Further research is warranted to explore the factors influencing ONSD dynamics and to establish standardized, patient-centered measurement protocols

Clinical anatomy of the macula

Background: The macula is located at the center of the retina and is crucial for high-resolution color vision. Its complex anatomical structure supports a dense array of cone photoreceptors and specialized neuronal pathways essential for central vision. A thorough understanding of macular microanatomy is vital for accurate interpretation of retinal imaging and effective management of macular diseases. This narrative review provides a detailed and integrative overview of macular anatomy, emphasizing clinically relevant microanatomical features and their implications in retinal imaging and macular disease management. Methods: A PubMed/MEDLINE search was performed using relevant keywords (e.g., “anatomy,” “fovea,” “foveal avascular zone,” “foveola,” “Henle fiber layer,” “macula,” “macular anatomy,” “macula lutea,” “optical coherence tomography,” “parafovea,” “perifovea,” and “retina”) to identify English-language articles published up to February 28, 2025. The reference lists of the included papers were manually reviewed to identify additional relevant sources. The review considered a wide range of study types, including clinical trials, systematic and narrative reviews, meta-analyses, observational studies, case series, and experimental animal studies. Results: This review highlights the remarkable characteristics of the fovea and foveola, which are densely packed with cone photoreceptors, making them uniquely suited for sharp vision. The surrounding parafoveal and perifoveal regions offer critical structural and functional support, while the Henle fiber layer facilitates the oblique course of photoreceptor axons, further refining central vision. Moreover, high-resolution optical coherence tomography has revolutionized visualization of the macular architecture, enabling a detailed assessment of previously undetectable retinal layers. This review explores key anatomical features, such as the foveal avascular zone, precise photoreceptor organization, and the role of Muller glial cells, in the context of high-resolution imaging. These associations between anatomy and imaging enhance diagnostic precision and may inform targeted treatment approaches for macular diseases. Conclusions: Comprehensive knowledge of macular anatomy is crucial for the accurate interpretation of retinal imaging and management of central retinal disorders. The bridging of classic histological findings with modern imaging enhances comprehension of the healthy macula and the detection and management of pathological changes. This review serves as a practical anatomical reference for clinicians and researchers in macular diagnostics and therapeutics. Further studies are warranted to explore how emerging imaging technologies can enhance early detection and treatment strategies for macular disorders

A review on retinopathy of prematurity

Background: Retinopathy of prematurity (ROP) is a leading cause of childhood blindness. It predominantly affects preterm infants with very low birth weights or extreme prematurity. Aberrant retinal vascular development, driven by hyperoxia and hypoxia-induced neovascularization, is central to ROP pathogenesis. This review explores the relationship between maternal health and ROP, evaluates current prevention strategies, assesses innovations in diagnostic and screening technologies, reviews contemporary treatments, and identifies future research directions. Methods: A literature review was conducted in the PubMed / MEDLINE, Scopus, Web of Science, and Google Scholar databases using related keywords, i.e., “retinopathy of prematurity,” “retinal development,” “pathophysiology,” “vascular growth,” “complications,” “visual outcomes,” “maternal health factors,” “obstetrics,” “preeclampsia,” “risk factors,” “preterm birth,” “corticosteroids,” “oxygen management,” “treatment strategies,” “laser therapy,” “anti-VEGF agents,” “surgical approaches”, and “artificial intelligence (AI)” and targeting English studies published in the last 20 years. Additionally, the references from the selected articles were manually reviewed. Clinical trials, meta-analyses, systematic reviews, case–control studies, case series, narrative reviews, pilot studies, and relevant animal studies were included. Results: Maternal factors, such as diabetes, smoking, and preeclampsia, along with neonatal factors, such as low gestational age and extreme prematurity, are critical contributors to ROP. Key preventative strategies to reduce the risk of ROP and improve neonatal outcomes include: 1. prenatal care involves screening and managing maternal conditions, providing maternal education, and administering antenatal corticosteroids. 2. Neonatal care encompasses nutritional support, supplementation with essential fatty acids, and regulated oxygen administration. By focusing on these strategies, we can enhance the health of newborns at risk for ROP. Advances in screening, including artificial intelligence (AI)-assisted diagnostics and advanced imaging, are improving early detection. Treatment modalities such as laser photocoagulation, cryotherapy, and anti-vascular endothelial growth factor therapies have shown promise but pose challenges, including recurrence risk and systemic side effects. Conclusions: ROP continues to pose a major threat to the vision of preterm infants, particularly in regions with limited healthcare resources. Addressing ROP requires multidisciplinary team approaches that integrate obstetric and neonatal care. Preventative strategies, including prenatal care optimization, oxygen management, and nutritional support, are essential. Future efforts should focus on integrating emerging technologies and recent findings to ensure global relevance and currency

Artificial intelligence in ophthalmology: opportunities, challenges, and ethical considerations

Background: By leveraging the imaging-rich nature of ophthalmology and optometry, artificial intelligence (AI) is rapidly transforming the vision sciences and addressing the global burden of ocular diseases. The ability of AI to analyze complex imaging and clinical data allows unprecedented improvements in diagnosis, management, and patient outcomes. In this narrative review, we explore the current and emerging opportunities of utilizing AI in the vision sciences, critically examine the associated challenges, and discuss the ethical implications of integrating AI into clinical practice. Methods: We searched PubMed/MEDLINE and Google Scholar for English-language articles published from January 1, 2005, to March 31, 2025. Studies on AI applications in ophthalmology and optometry, focusing on diagnostic performance, clinical integration, and ethical considerations, were included, irrespective of study design (clinical trials, observational studies, validation studies, systematic reviews, and meta-analyses). Articles not related to the use of AI in vision care were excluded. Results: AI has achieved high diagnostic accuracy across different ocular domains. In terms of the cornea and anterior segment, AI models have detected keratoconus with sensitivity and accuracy exceeding 98% and 99.6%, respectively, including in subclinical cases, by analyzing Scheimpflug tomography and corneal biomechanics. For cataract surgery, machine learning-based intraocular lens power calculation formulas, such as the Kane and ZEISS AI formulas, reduce refractive errors, achieving mean absolute errors below 0.30 diopters and performing particularly well in highly myopic eyes. AI-based retinal screening systems, such as the EyeArt and IDx-DR, can autonomously detect diabetic retinopathy with sensitivities above 95%, while deep learning models can predict age-related macular degeneration progression with an area under the receiver operating characteristic curve exceeding 0.90. In glaucoma detection, fundus and optical coherence tomography-based AI models have reached pooled sensitivity and specificity exceeding 90%, although performance varies with disease stage and population diversity. AI has also advanced strabismus detection, amblyopia risk prediction, and myopia progression forecasting by using facial analysis and biometric data. Currently, key challenges in implementing AI in ophthalmology include dataset bias, limited external validation, regulatory hurdles, and ethical issues, such as transparency and equitable access. Conclusions: AI is rapidly transforming vision sciences by improving diagnostic accuracy, streamlining clinical workflow, and broadening access to quality eye care, particularly in underserved regions. Its integration into ophthalmology and optometry thus holds significant promise for enhancing patient outcomes and optimizing healthcare delivery. However, to harness the transformative potential of AI fully, sustained multidisciplinary collaboration, involving clinicians, data scientists, ethicists, and policymakers, is essential. Rigorous validation processes, transparency in algorithm development, and strong ethical oversight are equally important to mitigate risks such as bias, data misuse, and unequal access. Responsible implementation of AI in the vision sciences is essential to ensure that all populations are served equitably

Depression, anxiety, and stress indicators for patients who are blind or visually impaired

Background: Severe visual impairment is reportedly detrimental to mental health. Blind individuals are expected to have poorer mental health status compared to those with low vision. However, most mental health studies have focused on people with low vision, leaving a substantial gap in our understanding of the mental health status of the blind. Therefore, this study compared the mental health status of individuals with low vision to that of blind individuals. Methods: This cross-sectional, questionnaire-based investigation involved individuals with low vision or blindness who were registered with the Social Welfare Department, Federal Territory of Kuala Lumpur, Malaysia. Participants were recruited using a simple random sampling method. The medical records of each participant were screened. Participants were individually interviewed, and their socio-demographic details, education level, working status, marital status, type and duration of impairment, and rehabilitation status were collected. Additionally, the Depression, Anxiety, and Stress Scale (DASS-21) was administered to each individual. Results: Of the 30 participants, 20 (66.7%) had low vision and 10 (33.3%) had blindness, 16 (53.3%) were men, and most participants were single (n = 20, 66.7%). Congenital and acquired causes of visual impairment each accounted for 50% of cases. Most participants (n = 26, 86.7%) had not received psychosocial rehabilitation. The mean DASS-21 scores for the depression, anxiety, and stress subscales were significantly higher in patients with low vision than in those with blindness (all P < 0.05). Considering the clinical cut-off increments to determine emotional states for the DASS-21 subscales, individuals with low vision were in the mild, moderate, and mild categories for the depression, anxiety, and stress subscales, respectively. Individuals with blindness were categorized as normal in all subscales. The mean DASS-21 scores for the depression, anxiety, and stress subscales among individuals with congenital and acquired causes of visual impairment were comparable (all P > 0.05). Individuals with congenital visual impairment were in the normal, moderate, and normal categories for the depression, anxiety, and stress subscales, respectively. Those with acquired visual impairment were categorized as mild, moderate, and normal for the depression, anxiety, and stress subscales, respectively. Conclusions: Individuals with low vision experienced mild to moderate levels of mental health issues, which may consist of depression, anxiety, stress, or a combination of these. The blind individuals in this study demonstrated no similar mental health issues. The small number of participants in certain racial and age groups prevents us from concluding how these factors might influence mental health. Further research with a larger sample size should consider the severity of visual impairment, age groups, and ethnicity, as these factors may impact the outcomes

A comparative study and review of visual outcomes with enhanced versus standard monofocal intraocular lenses following cataract surgery

Background: Recent innovations in intraocular lens (IOL) design have introduced extended depth of focus lenses, which has shown promise in improving visual acuity at multiple distances while preserving the distance vision provided by a standard monofocal IOL. This study aimed to evaluate the visual outcomes of TECNIS Eyhance, a monofocal IOL with enhanced intermediate function, and a standard TECNIS monofocal 1-piece IOL, and to review published studies comparing the clinical performance between the TECNIS Eyhance and standard IOLs. Methods: A retrospective analysis was conducted on patients who underwent cataract extraction with bilateral implantation of either TECNIS Eyhance IOLs or TECNIS Monofocal 1-Piece IOLs. Primary outcomes included monocular and binocular uncorrected distance visual acuity (UDVA), uncorrected near visual acuity (UNVA), and corrected distance visual acuity (CDVA), and manifest refraction. Outcomes such as glare, halos, and dry eye were also assessed. A literature review was performed to identify studies evaluating the clinical outcomes of TECNIS Eyhance and standard TECNIS monofocal IOLs. Results: In total 108 patients (216 eyes) underwent bilateral implantation with either TECNIS Eyhance (104 eyes) or TECNIS Monofocal 1-Piece (112 eyes) IOLs. The mean (standard deviation [SD]) binocular UNVA was better in the Eyhance group at 1 month (0.18 [0.13] logMAR) compared to the standard monofocal group (0.24 [0.14] logMAR; P < 0.05). A greater proportion of Eyhance patients achieved binocular UNVA of 20/25 or better (46.9% vs 21.8%; P < 0.01), and 20/32 or better (65.3% vs 45.5%; P < 0.05). However, there was no significant difference for 20/20 visual acuity (20.4% vs 18.2%; P > 0.05). No significant differences were observed in postoperative UDVA or CDVA between groups (both P > 0.05). The mean (SD) monocular UNVA showed a slight, but non-significant, advantage in the Eyhance group (0.26 [0.15] logMAR vs 0.29 [0.15] logMAR; P > 0.05). Eyhance eyes demonstrated less residual refractive cylinder at 1 month (P < 0.01), which may be attributed to a higher rate of toric IOL use (P < 0.01). Patient-reported visual symptoms did not differ between groups. Thirteen studies were identified that compared the Eyhance and standard monofocal IOLs. Across the studies analyzed, the Eyhance group showed better monocular and binocular UNVA with mean (SD) differences of - 0.10 (0.20) logMAR and - 0.10 (0.21) logMAR, respectively (both P < 0.01), as well as improved binocular uncorrected intermediate visual acuity (UIVA) (mean difference [SD]: -0.10 [0.18] logMAR; P < 0.01). These studies also showed low rates of glare and halos for both IOLs. Conclusions: Patients receiving the TECNIS Eyhance IOL had better binocular UNVA compared to those with a standard monofocal IOL, consistent with published literature. The Eyhance IOL also showed better binocular UIVA and monocular UNVA across the studies reviewed. Both enhanced and standard monofocal IOLs demonstrate excellent distance vision and have similar levels of photic phenomena. Nevertheless, the Eyhance IOL shows promising potential for improving intermediate and near vision