Journal of Ophthalmic and Vision Research

Editorial – Keratoprosthesis Surgery: Evolution and Global Adaptations

2024-11-21T08:43:18+00:00

This is an Editorial and does not have an abstract. Please download the PDF or view the article in HTML.

Doxycycline versus Curcumin for Inhibition of Matrix Metalloproteinase Expression and Activity Following Chemically Induced Inflammation in Corneal Cells

2024-11-21T08:45:06+00:00

Purpose: Sulfur mustard (SM) is a potent blistering agent. This alkylating chemical agent has extremely toxic effects on the eye. MMP-2 and MMP-9 are the two most important matrix metalloproteinase enzymes involved in the pathology of chemical eye injuries. Curcumin is regarded as a natural anti-inflammatory agent. This study aims to compare the anti-inflammatory effects of curcumin versus doxycycline on chemically induced corneal injuries.
Methods: The HCE-2 cell line was used as a model for corneal cells. The effective concentrations of 2-chloroethyl ethyl sulfide (CEES) – as an analog of SM – doxycycline, and curcumin were determined using the MTT assay. The gene expression of MMP-2, MMP-9, and tissue inhibitors of metalloproteinase (TIMP-1) was evaluated by the real-time PCR method. Also, the activity of MMP-2 and MMP-9 enzymes was determined by zymography.
Results: The expression of the MMP-2 and MMP-9 genes increased 5- and 3.3-fold after exposure to CEES, respectively. Following the treatment with curcumin and doxycycline, MMP- 2 expression decreased significantly. Also, after treatment with curcumin and doxycycline, the MMP-9 expression decreased 2.5- and 1.6-fold, respectively. The reduction in activity was 32% for MMP-2 and 56% for MMP-9 after treatment with curcumin. The corresponding values were 12% and 40% following doxycycline treatment. There was no significant difference between the effects of curcumin and doxycycline on reducing MMP-2 expression, but the difference was statistically significant in the case of MMP-9.
Conclusion: Doxycycline and curcumin can inhibit MMP expression and activity in chemically exposed corneal cells. Curcumin has a greater ability than doxycycline to inhibit MMP-2 and MMP- 9 enzymes; however, the difference is statistically significant only in the case of MMP-9. After further validation, these substances can be introduced as anti- inflammatory agents to treat corneal chemical burns.

Clinical Manifestations and Outcomes of Ocular Graft Versus Host Disease following Allogeneic Stem Cell Transplantation

2024-11-21T08:45:19+00:00

Purpose: To evaluate clinical presentation of chronic ocular graft-versus-host disease (GVHD), laterality of presentation, and longitudinal changes in patients undergoing allogeneic stem cell transplantation.

Methods: This is a retrospective longitudinal analysis of 60 eyes from 30 patients who had undergone hematopoietic stem cell transplantation. Demographic characteristics, clinical history, comorbidities, and other organ involvements were taken into account for analysis. We also undertook complete evaluation of the eyes, including cornea and anterior segment, posterior segment, Schirmer test, tear break-up time, ocular surface disease index, and intraocular pressure.

Results: The mean age of the patients was 34.3 ± 11 years. The mean time for the diagnosis of ocular GVHD was 232.8 days (95% CI: 153.6, 311.9). The common findings at the first visit were bilateral blepharitis (n = 5, 17%), meibomitis (n = 4, 13%), and conjunctival congestion (n = 3, 10%). While bilateral cataract was present in one (3%) patient at the first visit, at 18 months, five (17%) patients had bilateral cataract and one (3%) patient had unilateral cataract. Grade 1 (n = 17), grade 2 (n = 9), and grade 3 (n = 4) superficial punctate epithelial erosions (SPEEs) were also observed at the first visit. However, SPEEs were seen in only 11 eyes at 18 months; all of these cases were grade 1 SPEEs. Long-term findings included cataract, telangiectasia, blepharospasm, conjunctival congestion, grade 1 SPEEs, corneal filaments, and tear film debris.

Conclusion: Although the initial presentations were SPEEs, meibomitis, blepharitis, and conjunctival congestion, these inflammatory conditions were reduced over time with proper management. However, there was an increase in the proportion of patients with cataract. It is important to regularly monitor these patients in order to identify and manage the initial as well as the late ocular manifestations of chronic GVHD.

Clinical Outcomes of Stage 2 (Pivotal) Use of a Modified Keratoprosthesis Device (ORC-KPro) in Patients with End-stage Corneal Blindness

2024-11-21T08:45:16+00:00

Purpose: To investigate the short-term results and performance of a modified Boston keratoprosthesis device manufactured by the Ophthalmic Research Center (ORC-KPro) in patients with end-stage corneal blindness.

Methods: This prospective interventional case series was conducted on patients with corneal blindness who were candidates for KPro. The inclusion criterion comprised patients with a bestcorrected visual acuity (BCVA) of less than 20/200 in both eyes, in whom the main reason for vision loss was corneal pathology. The ORC-KPro was implanted using the method previously described for Boston KPro.

Results: This study focused on 12 eyes of 12 patients with an average age of 45.9 ± 16.8 (range, 19 to 70) years. Eleven patients were male. The KPro indication was corneal blindness due to chemical burns in nine patients (75%) and failure of multiple previous corneal grafts in three patients (25%). Anatomical success was achieved in all patients. The preoperative BCVA was light perception (LP) in 10 eyes and hand motion in 1 eye. Except for one patient who was diagnosed with grade C proliferative vitreoretinopathy during the surgery, the vision of all other patients (91.6%) improved after surgery. The retroprosthetic membrane (RPM) was formed in two eyes (18.1%) after six months. Of the 12 patients, 10 (83.3%) were under treatment with two antiglaucoma medications before surgery. The intraocular pressure of three eyes (25%) was estimated to be high by tactile palpation; however, it decreased in two eyes to the acceptable range. One patient underwent retinal surgery due to total retinal detachment, and two patients (16.7%) underwent vitrectomy due to endophthalmitis.

Conclusion: The current study showed that, in the short term, the use of ORC-KPro achieved favorable anatomical success in patients with corneal blindness. However, the functional success rate was limited by the low visual potential due to advanced glaucoma in most patients.

Visual and Demographic Risk Factors for Falls and the Impact of Cataract Surgery in Elderly Patients

2024-11-21T08:45:11+00:00

Purpose: To evaluate the effect of cataract surgery and visual impairment and the associated risk factors on the frequency of falls among older adults in northeast Iran.

Methods: This cross-sectional study, conducted between 2019 and 2020, analyzed the potential risk factors of falling in older adults over 50 years of age. To this end, 380 patients were randomly selected by convenience sampling and classified into two groups: those who had undergone cataract surgery in the last 12 months (surgery group) and those who had not (cataract group). The data were collected from the medical records and face-to-face interviews, and logistic regression was used to identify potential risk factors for falling.

Results: The frequency of falls in the cataract and surgery groups was 18.9% and 11.6%, respectively. The mean decimal visual acuity of the dominant eye was significantly lower in the cataract group than in the surgery group (P < 0.001). There were no significant differences in the mean number of medications used, Charlson Comorbidity Index score, Instrumental Activities of Daily Living score, and 10-Meter Walk Test speed between the two groups. According to the results of backward logistic regression, taking more than four medications per day and slow gait speed were the most important factors influencing the frequency of falls in older adults.

Conclusion: Logistic regression analysis indicated that undergoing cataract surgery is not a significant protective factor against falls. However, older adults in the surgery group experienced fewer falls than in the other group. Besides, the results suggest that taking more than four medications daily and having a slow gait speed are significant fall risk factors.

Evaluation of Foveal Vasculature by Optical Coherence Tomography Angiography after Pan-Retinal Photocoagulation versus Intravitreal Anti-VEGF Injections

2024-11-21T08:45:09+00:00

Purpose: This study aimed to compare macular vascular changes one and three months after treatment with either panretinal photocoagulation (PRP) or intravitreal bevacizumab (IVB).

Methods: A total of 62 eyes with very severe non-proliferative diabetic retinopathy or early proliferative diabetic retinopathy without center-involved diabetic macular edema, were included in this retrospective study. Thirty-nine eyes were allocated to the PRP group, while 23 eyes were treated with IVB. Optical coherence tomography angiography (OCTA) was performed to measure foveal avascular zone (FAZ) characteristics as well as the densities of superficial and deep capillary plexuses (SCP and DCP).

Results: In the IVB group, the FAZ area and perimeter expanded at month one but returned to baseline level after three months. In the PRP group, however, the FAZ area and perimeter were rather steady. Changes in the FAZ area were significantly different between the treatment groups at month one (P = 0.02), but not at month three (P = 0.31). There was no significant difference in the change in FAZ circularity index between the two groups at each time point (P = 0.55 and P = 0.31). Similarly, changes in SCP density were not statistically significant between the two groups at both time points (all Ps > 0.05). A comparison of the two treatment arms based on the mean change in DCP density revealed a significant difference at month one, but not at month three (P = 0.01 and P = 0.49, respectively).

Conclusion: Although bevacizumab and PRP have different short-term macular vascular responses, both therapies have the ability to normalize or stabilize vascular measures over time.

Predictive Factors for Functional and Anatomical Outcomes After Anti-VEGF Treatment for Macular Edema in Patients with Branch Retinal Vein Occlusion

2024-11-21T08:45:14+00:00

Purpose: This study aimed to identify predictive factors for the improvement of best-corrected visual acuity (BCVA) and reduction of central macular thickness (CMT) after treatment of macular edema (ME) due to branch retinal vein occlusion (BRVO) in a real-world setting.

Methods: This retrospective study included patients with ME secondary to BRVO who were treated with intravitreal injection of bevacizumab as the first-line therapy and were followed up for 12 months. Demographic and clinical data, in addition to baseline spectral domain optical coherence tomography (SD-OCT) features, were considered as possible biomarkers of final BCVA and CMT. We also collected the data concerning the need for additional treatment including sectorial laser photocoagulation, change to another anti-VEGF agent, or intravitreal corticosteroid injection.

Results: A total of 161 eyes were analyzed. BCVA significantly improved from baseline to 12- month follow-up (0.6 and 0.4 logMAR, respectively; P < 0.01). CMT decreased significantly during the follow-up period (from 498.0 to 325.0 μm; P < 0.01). Final BCVA correlated positively with baseline BCVA (P < 0.01, r = 0.57). Older age at diagnosis and baseline SD-OCT findings including CMT, disruption of the retinal inner layers, retinal pigment epithelium (RPE) damage, and impairment of the ellipsoid zone and external limiting membrane negatively affected final BCVA (P < 0.01). Multiple regression analysis identified age and BCVA at baseline as the only independent predictors of final BCVA (P = 0.001 and P < 0.01, respectively). No association was found between clinical data, SD-OCT parameters, and final CMT.

Conclusion: Various clinical and SD-OCT parameters are prognostically relevant for visual improvement in ME secondary to BRVO. Age at diagnosis and baseline BCVA were found to be independent predictors of visual outcome.

Type and Frequency of Misdiagnosis and Time Lag to Diagnosis in Patients with Chronic Progressive External Ophthalmoplegia

2024-11-21T08:45:00+00:00

Purpose: Since ptosis is an early feature of chronic progressive external ophthalmoplegia (CPEO), patients are commonly misdiagnosed with other causes of ptosis. This study aims to report the type and frequency of misdiagnosis and time lag to diagnosis and the palpebral fissure transfer (PFT) procedure in patients with CPEO.
Methods: This is a retrospective analysis of consecutive patients with CPEO who underwent PFT between 2006 and 2017. The data on previous diagnoses and treatments, age at definitive diagnosis of CPEO, and clinical manifestations were recorded. While the diagnosis of CPEO was based on clinical examination, 75% (24/32) of patients had undergone a confirmatory muscle biopsy and genetic tests.
Results: There were 32 patients (19 females) with a mean age of 24.8 years (range, 13–36) at the final diagnosis and 34.1 years (range, 15–56) at the time of PFT. Also, 78% (25/32) of patients had been initially misdiagnosed with congenital ptosis (60%; 15/25) and ocular myasthenia gravis (OMG) (40%; 10/25). The majority of patients (20/32) had one to three previous eyelid surgical procedures, of which 90% (18/20) were performed before the definitive diagnosis of CPEO. The mean time lag from the first surgical procedure to CPEO diagnosis and PFT was 6.2 and 14.7 years, respectively.
Conclusion: In a referral center, 78% of the patients with CPEO were initially misdiagnosed with congenital ptosis and OMG, and 56% of them underwent ptosis repair before the diagnosis. While the onset of the disease was in the first or second decades of life, diagnosis was delayed up to a mean age of 25 years. Reviewing early family photos and paying attention to other signs of CPEO could prevent misdiagnosis.

Intravenous Tranexamic Acid for Control of Bleeding during External Dacryocystorhinostomy under General Anesthesia: A Randomized Clinical Trial

2024-11-21T08:45:01+00:00

Purpose: To investigate the effect of intravenous tranexamic acid administered prior to external dacryocystorhinostomy (DCR) surgery to decrease intraoperative bleeding under general anesthesia.
Methods: This was a double-blinded randomized placebo-controlled trial. A total of 70 patients (35 intervention and 35 control) with nasolacrimal duct obstruction (NLDO) who were selected for DCR surgery between September 2021 and September 2022 were included. After clinical examinations and laboratory tests, patients were randomly classified into intervention and control groups. The intervention group received 10 mg/kg intravenous tranexamic acid to a maximum dose of 1 gr 30 minutes before the surgery. Controls received normal saline solution as a placebo. The amount of intraoperative bleeding and surgical time were compared between the two groups.
Results: The intervention group included 21 men (60%) and 14 women (40%), while the control group included 19 men (54.3%) and 16 women (45.7%). The mean ages of the participants were 55.46 ± 10.8 years and 58.06 ± 11.28 years in the intervention and control groups, respectively. A significant difference was observed between the two groups in the surgical time analysis (control group: 37.74 ± 9.52 minutes vs intervention: 26.03 ± 10.5 minutes; P < 0.001). Additionally, there was a significant difference in the bleeding volume between the intervention (70.66 ± 48.19 ml) and control (47.74 ± 60 ml) groups (P < 0.001).
Conclusion: Intravenous tranexamic acid administration before the DCR procedure can successfully control bleeding during the surgery.

Investigating Optic Nerve Sheath Diameter in Prone Position Spinal Surgery Patients: A Pilot Study

2024-11-21T08:45:04+00:00

Purpose: This study aimed to evaluate the effect of intraoperative positioning and ocular immobility on the amount of cerebrospinal fluid around the optic nerve in patients undergoing prone spinal surgery by measuring the optic nerve sheath diameter (ONSD) using ultrasound.
Methods: Consecutive participants (n = 15 patients, 30 eyes) were scanned preoperatively, intraoperatively approximately 20 minutes before the end of the surgery, and postoperatively in the post-anesthesia care unit at least 10 min after the completion of the surgery at one academic hospital.
Results: On average, patients who underwent prone spinal surgery had a 21% increase in ONSD intraoperatively, with a positive time-dependent relationship with the overall length of surgery (P < 0.001). ONSDs postoperatively returned to baseline and were not significantly different from preoperative measurements.
Conclusion: Our findings suggest pooling and inadequate clearance of perioptic cerebrospinal fluid during prone spinal surgery that improves following termination of the procedure and return of the patient to an upright position.

Application of Artificial Intelligence in Ophthalmology: An Updated Comprehensive Review

2024-11-21T08:44:09+00:00

Artificial intelligence (AI) holds immense promise for transforming ophthalmic care through automated screening, precision diagnostics, and optimized treatment planning. This paper reviews recent advances and challenges in applying AI techniques such as machine learning and deep learning to major eye diseases. In diabetic retinopathy, AI algorithms analyze retinal images to accurately identify lesions, which helps clinicians in ophthalmology practice. Systems like IDx- DR (IDx Technologies Inc, USA) are FDA-approved for autonomous detection of referable diabetic retinopathy. For glaucoma, deep learning models assess optic nerve head morphology in fundus photographs to detect damage. In age-related macular degeneration, AI can quantify drusen and diagnose disease severity from both color fundus and optical coherence tomography images. AI has also been used in screening for retinopathy of prematurity, keratoconus, and dry eye disease. Beyond screening, AI can aid treatment decisions by forecasting disease progression and anti- VEGF response. However, potential limitations such as the quality and diversity of training data, lack of rigorous clinical validation, and challenges in regulatory approval and clinician trust must be addressed for the widespread adoption of AI. Two other significant hurdles include the integration of AI into existing clinical workflows and ensuring transparency in AI decisionmaking processes. With continued research to address these limitations, AI promises to enable earlier diagnosis, optimized resource allocation, personalized treatment, and improved patient outcomes. Besides, synergistic human-AI systems could set a new standard for evidence-based, precise ophthalmic care.

Immune Checkpoints and Graves’ Disease, Thyroid Eye Disease, and Orbital Myopathy: A Comprehensive Review

2024-11-21T08:44:57+00:00

Immune checkpoints (ICPs) are essential regulators of the immune system, ensuring a delicate balance between self-tolerance and autoimmune responses. ICP therapy is a rapidly growing cancer treatment strategy that inhibits the interaction between ICPs and their ligands. This biological interaction increases the ability of the immune system in combating cancer. However, in some cases, the use of these agents may lead to immune hyperactivity and, subsequently, autoimmune diseases. Graves’ disease (GD), thyroid eye disease (TED), and orbital myopathy are complex autoimmune disorders characterized by the production of autoantibodies. The emergence of these treatment-related adverse events underscore the critical need for a deeper understanding of the immune-checkpoint axis in autoimmune diseases. In this review article, we provide a comprehensive survey of the biological mechanisms of ICPs that are most frequently targeted in cancer therapy, including CTLA-4, PD-1, PDL-1, and LAG3. Furthermore, we investigate the latest scientific findings on the adverse events associated with the inhibition of these ICPs. This paper will particularly focus on the potential risks these complications pose to ocular and orbital tissues, which are a concern in the context of cancer treatment.

Late Metastasis in Conjunctival Adenosquamous Carcinoma

2024-11-21T08:45:21+00:00

Purpose: To present a rare case of metastatic conjunctival adenosquamous carcinoma (ASC) in the context of limited literature on the prognosis of ASC and suggested follow-up and surveillance.
Case Report: We report a case of conjunctival ASC that metastasized to cervical lymph nodes five years after histological confirmation of complete local excision.
Conclusion: Long-term clinical follow-up and surveillance imaging are warranted to allow early detection of disease recurrence and/or metastasis.

XEN Gel Stent Failure Due to Luminal Obstruction

2024-11-21T08:45:23+00:00

Purpose: To discuss four cases of post-operative XEN gel stent luminal obstruction in patients with primary open angle glaucoma.
Case Report: Four eyes in three patients with primary open angle glaucoma who received XEN stent implantation were found to have luminal obstruction of their stents. Stent obstruction can mimic filtering bleb failures not responding to bleb needling and antimetabolite injections. These obstructions were suspected to result from fibrin clots, iris pigment granules, or breakdown products of intraocular inflammation or hemorrhage. Treatment options trialed in these patients included bleb needling, 5-fluorouracil injection, and YAG laser to the proximal end of the XEN. Ultimately, all four eyes required XEN explantation and alternative filtering surgery.
Conclusion: XEN luminal obstruction is an important complication of stent placement that can ultimately lead to stent failure. Conservative measures such as laser or traditional bleb management may be considered before stent explantation or additional glaucoma surgery.