The 2021 Questionnaire Survey of the Korean Uveitis Society: Current Trends of Uveitis Diseases

Purpose: To report the results of a 2021 questionnaire survey assessing the current trends and practice patterns in the treatment of uveitis, conducted by the Korean Uveitis Society (KUS).Methods: To understand the current treatment and trends for uveitis in Korea, a total of 11 questions were surveyed in November 2021 among 300 members of the KUS. This survey comprised 11 multiple choice and dichotomy questions.Results: Of 300 participants, 179 responded, and the response rate was 59.7%. Among the respondents, 92.7% were retina specialists and 66.9% reported less than 10% of uveitis patients among outpatients. As imaging tests performed in patients with anterior uveitis, fundus photography and optical coherence tomography were typically performed (83.8% vs. 73.2%, respectively). The frequently performed blood tests for general screening were complete blood count, blood chemistry test, erythrocyte sedimentation rate, and C-reactive protein (89.9% vs. 86.2% vs. 85.5% vs. 82.4%, respectively). Regarding local steroid treatment, subtenon injection was the most preferred (74.9%). Regarding systemic oral corticosteroids, 83.7% of respondents commonly used initial doses of 0.5-1 mg/kg. Cyclosporine, methotrexate, mycophenolate mofetil, and azathioprine were used for steroid-refractory uveitis patients in that order (36.2% vs. 34.8% vs. 21.7% vs. 7.3%, respectively). Concerning the currently used biologic agent, adalimumab was the most preferred, at 96.7%.Conclusions: This survey highlights the recent trends and practice patterns in the treatment of uveitis in Korea.

Localized versus 360-degree laser photocoagulation with limited pars plana vitrectomy in the management of primary rhegmatogenous retinal detachment

Background

To compare the efficacy of intraoperative localized and 360-degree laser photocoagulation in 23-gauge limited pars plana vitrectomy (PPV) for rhegmatogenous retinal detachment (RRD).

Methods

This retrospective, comparative, consecutive, interventional study included 155 eyes of 155 patients who underwent primary repair of RRD utilizing 23-gauge PPV with at least six months of follow up. Medical records were retrospectively reviewed, and the corresponding demographic data, preoperative ophthalmic features, surgical management, and postoperative course were recorded. Main outcome measures included single surgery anatomical success, pre- and post-operative visual acuity, and complications.

Results

Eighty-three patients (group A) received localized laser photocoagulation in PPV, while the remaining 72 patients (group B) received underwent circumferential 360-degree laser photocoagulation in PPV. Two skilled-surgeons performed all the surgeries, and 23-gauge PPV instrumentation, a wide-angle viewing system, endolaser photocoagulation, and gas tamponade were used in each case. No significant difference was identified in baseline characteristics. The single surgery anatomical success rate was 96.4 % in group A, and 95.8 % in group B, showing no significant difference (p = 1.00). Primary anatomical failure was caused by re-detachment due to break in 2 eyes in each group (no new break 1 eye, new break 1eye in group A, 2 eyes with no new break in group B), and proliferative vitreoretinopathy in 1 eye in each group. Other complications were epiretinal membrane in 7 eyes (3 in group A, 4 in group B), and macular hole in 1 eye in group B. There were no differences in pre- and post-operative best-corrected visual acuity (BCVA) as well as BCVA improvement (p=0.144, p=0.866 and p=0.263, respectively).

Conclusion

Localized laser photocoagulation showed no difference in anatomic and visual outcome in RRD patients, when compared with 360-degree laser photocoagulation in limited PPV. Routine circumferential 360-degree laser photocoagulation may not be necessary in vitrectomy surgery for primary rhegmatogenous retinal detachment without severe PVR.

Effect of Foveal Pit Restoration in Foveal Avascular Zone After Surgery for idiopathic Epiretinal Membrane

Purpose

To investigate the relationship between ophthalmic parameters—including optical coherence tomography (OCT) and OCT angiography findings—and foveal pit restoration in eyes that had undergone vitrectomy for idiopathic epiretinal membrane (iERM) removal.

Methods

This study retrospectively analyzed data of patients who underwent pars planar vitrectomy for the removal of epirentinal membrane. Only eyes with iERM above stage 2 with a follow-up over 6 months were included. Baseline data and changes in ophthalmic parameters were analyzed from 3 months before to 12 months after surgery. Additionally, we stratified iERM patients into two groups (foveal pit restoration and no restoration group). Longitudinal comparison analyses between the two groups were done in best-corrected visual acuity (BCVA), central foveal thickness (CFT) and foveal avascular zone (FAZ) areas measurements using swept-source OCT and OCT angiography.

Results

Forty-three patients with a mean age of 75 ± 5 years were enrolled. After surgery, BCVA, FAZ, and CFT showed improvements over time (all p < 0.002). Thirty-one patients were designated into the foveal pit restoration (R) group and 12 patients into the no restoration (NR) group. Differences in BCVA and FAZ area in both groups existed up to 6 months. However, BCVA improved and FAZ expanded (R, 0.20 ± 0.05 vs. NR, 0.18 ± 0.04) in both groups showing no statistical difference 12 months postsurgery. The CFT decreased in both groups, but the R group was thinner at every point compared to the NR group (all p < 0.05).

Conclusions

The removal of epirentinal membrane in pars planar vitrectomy significantly improves BCVA, decreases the CFT and expands the FAZ. Foveal pit restoration improves BCVA, CFT, and FAZ area possibly at a faster rate in the early months but long-term improvements could be achieved regardless of the status of foveal pit restoration.

Preclinical Efficacy and Safety of VEGF-Grab, a Novel Anti-VEGF Drug, and Its Comparison to Aflibercept

Purpose

VEGF-Grab is a novel anti-vascular endothelial growth factor (VEGF) candidate drug with higher affinity to both VEGF and placental growth factor (PlGF) compared to aflibercept. We investigated the preclinical efficacy of VEGF-Grab for ophthalmic therapy and compared it to that of aflibercept.

Methods

The in vitro anti-VEGF efficacy of VEGF-Grab was determined using VEGF-induced cell proliferation/migration and tube formation assays. The in vivo antiangiogenic efficacy of intravitreal injection of either VEGF-Grab or aflibercept was evaluated using murine models of ocular angiogenesis: mouse oxygen-induced retinopathy (OIR) and rat laser-induced choroidal neovascularization (CNV). The in vivo retinal toxicity in the mouse eye resulting from the injection of either drug was evaluated with light and electron microscopy.

Results

VEGF-Grab showed greater inhibition of VEGF-induced cell proliferation/migration than aflibercept, but it showed comparable inhibition of tube formation in vitro. In the in vivo OIR model, VEGF-Grab showed a comparable suppression of retinal neovascularization compared to aflibercept. Additionally, VEGF-Grab showed an efficacy similar to that of aflibercept in terms of CNV inhibition in the laser-induced CNV model. Histology and transmission electron microscopy showed no significant signs of toxicity in the mouse retina at 7 and 30 days following the intravitreal injection of VEGF-Grab or aflibercept.

Conclusions

Compared to aflibercept, VEGF-Grab presented comparable in vivo antiangiogenic efficacy and superior in vitro anti-VEGF activity. The retinal safety profiles were comparable for the two drugs. Considering its known higher binding affinity to VEGF and PlGF compared to aflibercept, VEGF-Grab could be a potential candidate drug for neovascular retinal diseases and an alternative to aflibercept.

Laser and anti-vascular endothelial growth factor treatment for drusenoid pigment epithelial detachment in age-related macular degeneration

This study aims to report the 12 months results of efficacy and safety of laser photocoagulation and anti-vascular endothelial growth factor (VEGF) injections for drusenoid pigment epithelial detachment (dPED). In this prospective study, patients with treatment naïve bilateral intermediate age-related macular degeneration, featuring dPED, with visual acuity ≤ 83 letters were enrolled. The study group received PASCAL laser (532 nm) along the periphery of the dPED, and the fellow eye served as a control group. To prevent complications of choroidal neovascularization, intravitreal anti-VEGF injections to laser treated eye were performed on a 3-month interval up to 1 year. Primary outcomes—drusen area, PED height—and secondary outcomes—best-corrected visual acuity (BCVA), contrast sensitivity, degree of metamorphopsia, NEI-VFQ 25, and fundus autofluorescence—were analyzed. Among 21 patients, a total of 20 patients satisfied the 12 months follow-up. Drusen area and PED height decreased significantly in the laser group, while no significant change appeared in the control group (74.1% vs. − 3.5%, P < 0.001; 76.6% vs. 0.1%, P < 0.001). Mean BCVA improved 4.6 letters in the laser group (vs. 1.1 letters in the control group, P = 0.019). As for safety, one study eye developed retinal pigment epithelial tear, and one control eye developed retinal angiomatous proliferation. Low energy laser photocoagulation and anti-VEGF injection in eyes with dPED showed some improvement in visual acuity. dPED regressed without developing center involving GA in the study eye, but a longer term follow-up is necessary to reveal the efficacy and safety of these treatments. The 2-year results of this study will be followed to reveal long term efficacy and safety of the treatment for dPED.

Thickness of retina and choroid in the elderly population and its association with Complement Factor H polymorphism: KLoSHA Eye study

PURPOSE

To analyze the associations of retinal and choroidal thickness on enhanced-depth imaging optical coherence tomography (EDI-OCT) with clinical, ophthalmic and genetic factors in the normal elderly population (aged 65 years or older).

METHODS

In this prospective, population-based cohort study, people aged 65 years or older were enrolled in the baseline study of the Korean Longitudinal Study on Health and Aging (KLoSHA) Eye Study. All participants underwent spectral domain-OCT scan using the EDI technique. A topographic map of the retina was obtained and subfoveal choroidal thickness (SFCT) was measured manually. Blood samples from all subjects were genotyped for major age-related macular degeneration (AMD)-associated single nucleotide polymorphisms (SNPs) the major AMD-associated SNPs; CFH Y402H rs1061170, CFH I62V rs800292, ARMS2 A69S rs10490924. A statistical analysis was conducted to compare the retinal thickness, choroidal thickness, and AMD risk genotypes.

RESULTS

Among the three hundred eighty people enrolled, the mean age was 76.6 years (range 65-99 years). Factors that showed correlation with either tomographic retinal parameters, retinal nerve fiber layer, or SFCT, were age and gender. Significant age-related decrease in thickness was observed in the RNFL, mean central thickness (MCT) and SFCT. Gender differences existed in central foveolar thickness (CFT) and MCT, where it was thicker in men. While chorioretinal parameters were not related with other genotypes, CFH rs1061170 risk genotype was significantly associated with thin SFCT. The group containing the AMD- risk allele (CT) had a 14.7% reduction in the SFCT compared to the non-risk TT group.

CONCLUSIONS

In addition to the well-known association with AMD, CFH rs1061170 is a significant genetic risk factor associated with choroidal thinning in normal eyes of the elderly population. Such findings may provide further insight into the pathogenesis of age-related macular degeneration as well as normal aging. In addition, our study provides the first normative data on retinal and choroidal thickness in population-based aged groups with a mean age over seventy-five.

Therapeutic effects of a novel siRNA-based anti-VEGF (siVEGF) nanoball for the treatment of choroidal neovascularization

Age-related macular degeneration (AMD) is the leading cause of blindness in developed countries and is characterized by the development of choroidal neovascularization (CNV). Therapies for AMD have focused on suppressing angiogenic factors, such as vascular endothelial growth factor (VEGF), mainly via conventional anti-VEGF antibody agents. However, additional efforts have been made to develop effective small-interfering RNA (siRNA)-based intracellular therapeutic agents. In this study, we have manufactured a novel siRNA-based anti-VEGF nanoball (siVEGF NB). The siVEGF NB was composed of a siRNA hydrogel with a core of anti-VEGF sequence siRNA coated with branched PEI (bPEI) and hyaluronic acid (HA) in order by applying an electrical force. The novel siVEGF NBs, which were employed in a laser-induced CNV mouse model, were optimized as a retinal and choroidal delivery system through the vitreous humor to the sub-retinal space via CD44 receptor endocytosis on the inner limiting membrane, and showed therapeutic effects via pathways bypassing the TLR3-induced siRNA-class effect. The therapeutic effects of siVEGF NBs lasted for 2 weeks after intravitreal injection showing high targeting efficiency to the sub-retinal space. Thus, the newly developed siVEGF NB may have great potential for the delivery of RNAi-based therapeutics for ocular diseases, including AMD.

Proteomics-based identification and validation of novel plasma biomarkers phospholipid transfer protein and mannan-binding lectin serine protease-1 in age-related macular degeneration

Age-related macular degeneration (AMD) is a major cause of severe, progressive visual loss among the elderly. There are currently no established serological markers for the diagnosis of AMD. In this study, we carried out a large-scale quantitative proteomics analysis to identify plasma proteins that could serve as potential AMD biomarkers. We found that the plasma levels of phospholipid transfer protein (PLTP) and mannan-binding lectin serine protease (MASP)-1 were increased in AMD patients relative to controls. The receiver operating characteristic curve based on data from an independent set of AMD patients and healthy controls had an area under the curve of 0.936 for PLTP and 0.716 for MASP-1, revealing excellent discrimination between the two groups. A proteogenomic combination model that incorporated PLTP and MASP-1 along with two known risk genotypes of age-related maculopathy susceptibility 2 and complement factor H genes further enhanced discriminatory power. Additionally, PLTP and MASP-1 mRNA and protein expression levels were upregulated in retinal pigment epithelial cells upon exposure to oxidative stress in vitro. These results indicate that PLTP and MASP-1 can serve as plasma biomarkers for the early diagnosis and treatment of AMD, which is critical for preventing AMD-related blindness.

Incidence Rate of Massive Submacular Hemorrhage and its Risk Factors in Polypoidal Choroidal Vasculopathy

PURPOSE

To investigate the incidence rate of massive submacular hemorrhage (SMH) in patients with polypoidal choroidal vasculopathy (PCV) and analyze the associated risk factors.

DESIGN

Retrospective cohort study.

METHODS

Patients diagnosed with PCV from May 2003 to May 2014 were included. Two hundred forty-five eyes of 245 patients were enrolled. The time between the initial visit to the clinic with subjective visual symptoms and the date of massive SMH was recorded. SMH larger than 4 disc diameters was defined as massive SMH. Age; hypertension; visual acuity (VA); indocyanine green angiography findings, including the greatest linear dimension, largest polyp size, and PCV type (cluster vs non-cluster); and treatment methods were reviewed for risk factor analysis using Kaplan-Meier survival and Cox regression analyses.

RESULTS

The incidence rate of massive SMH within 1 year after the initial visit was 2.45%. Massive SMH occurred within 3, 5, and 10 years after the first visit in 6.17%, 11.09%, and 29.85% of patients, respectively. Cox regression analysis revealed that the cluster type of PCV was significantly associated with massive SMH (hazard ratio [HR], 3.418; P = .003). Photodynamic therapy followed by anti-vascular endothelial growth factor injection lowered the risk of massive SMH (HR = .242; P = .047]. Final VA in eyes with massive SMH was significantly lower than that in patients without massive SMH (1.34 ± 0.66 vs 0.63 ± 0.53 logMAR; P < .001).

CONCLUSIONS

Patients with PCV who develop massive SMH experience severe vision loss. The incidence rate of massive SMH in PCV increases with time. The cluster type of polyp in PCV is a significant risk factor for massive SMH.

Morphologic Characteristics of Choroid in the Major Choroidal Thickening Diseases, Studied by Optical Coherence Tomography

We investigated morphologic features of choroid in the choroidal thickening diseases, including central serous chorioretinopathy (CSC), polypoidal choroidal vasculopathy (PCV), and Vogt-Koyanagi-Harada disease (VKH), by a novel tomographic classification system of the choroid. This cross-sectional study involved 30 patients with active CSC, 30 patients with active PCV, and 27 patients with active VKH, and 30 normal controls. Utilizing enhanced depth imaging optical coherence tomography, we classified the morphology of the choroid into five categories: 1) Standard (S), 2) Dilated outer layer and Attenuated inner layer (DA), 3) Darkened (D), 4) Marbled (M), and 5) Pauci-Vascular (PV) types. Additional tomographic characteristics of the choroid such as choroidal vascular dilation, convolution, scleral invisibility, and choroidal hyper- or hypo-thickening were identified as well. The distribution of five choroidal tomographic morphology and additional tomographic characteristics in each group were analyzed. The DA type was observed in the CSC group more frequently than in the normal control group (53.3% vs 3.3%, P < 0.001). Additional tomographic characteristics, such as choroidal vascular dilation (76.7%), and choroidal hyper-thickening (36.7%), were more prevalent in the CSC group than in the control group. The PCV group showed higher prevalence of DA type (33.3% vs. 3.3%, P = 0.006) than the control group. The VKH group showed a significantly higher frequency of the D type (63.0%), convolution (40.7%), and scleral invisibility (70.4%) than controls (0% for all three findings). In conclusion, CSC and PCV shared common morphologic characteristics of choroid, including dilated outer vascular layer and focally attenuated innermost layer. Dense hypo-reflectivity and convolution of choroid were the specific tomographic markers for acute VKH. A new tomographic classification system of choroid may provide discrimination ability and insight into major pachychoroidopathies.

No-Reflow Phenomenon in Central Retinal Artery Occlusion: Incidence, Risk Factors, and Clinical Implications

PURPOSE

To investigate the incidence and risk factors of the no-reflow phenomenon in central retinal artery occlusion (CRAO) patients and to determine its effects on visual and anatomic outcomes.

METHODS

In 102 eyes with CRAO in which arterial recanalization was obtained within 1 week from baseline, fluorescein angiography images obtained at baseline and 1 week were retrospectively reviewed. The no-reflow phenomenon in the retina was defined as macular capillary nonperfusion following arterial recanalization on fluorescein angiographs. We investigated the incidence and risk factors for the no-reflow phenomenon and compared the anatomical and visual outcomes between eyes with and without the phenomenon.

RESULTS

Among the 102 CRAO eyes with arterial recanalization, 39 exhibited the no-reflow phenomenon, resulting in an incidence of 38.2%. The incidence among the eyes with treatment-induced and spontaneous recanalization was 43.4% and 15.8%, respectively, and it increased with the CRAO stage. CRAO stage and increased central macular thickness were risk factors for the phenomenon, with an odds ratio of 4.47 [95% confidence interval (CI), 1.19-16.8; P = 0.027] and 1.69 (95% CI, 1.12-2.55; P = 0.012) per 100-μm increase, respectively. The visual outcome was significantly poorer and retinal atrophy and photoreceptor disruption was greater in eyes with the no-reflow phenomenon than in those without.

CONCLUSIONS

The no-reflow phenomenon may occur after arterial recanalization in approximately one-third of CRAO patients and can affect anatomical and visual outcomes. This phenomenon may provide an additional explanation regarding the permanent retinal damage and vision loss in eyes with CRAO.

Ocular toxocariasis: clinical features, diagnosis, treatment, and prevention

Despite being one of the most common zoonotic infections worldwide, human toxocariasis has been one of the neglected tropical diseases. Although most human infections are asymptomatic, two main syndromes of human toxocariasis are classically recognized: systemic toxocariasis, which encompasses diseases in major organs; and ocular toxocariasis (OT), disease in the eye or optic nerve, caused by the migration of Toxocara larvae into the eye. OT is usually a unilateral disease, which typically presents as retinal granuloma, a yellowish or whitish inflammatory mass, in the posterior pole or peripheral retina. Granuloma itself or other comorbid conditions such as epiretinal membrane, macular edema, and retinal detachment can lead to permanent retinal damage and visual loss in eyes with OT. OT is diagnosed clinically by identification of clinical signs on ophthalmologic examination. Serological tests, such as enzyme-linked immunosorbent assay (ELISA) for detection of serum antibody against the Toxocara larvae, can confirm the diagnosis. In addition, serum immunoglobulin E and detection of ocular fluid antitoxocara antibody by ELISA may give additional aid to the diagnosis. Standard treatment of OT is corticosteroid in patients with active intraocular inflammation. Although the role of anthelmintic therapy is unclear, favorable outcome has been reported by combined corticosteroid and albendazole therapy in eyes with active inflammation. Prevention, by increasing public awareness and reducing the risk of infection, is also important. Recently, the association between ingestion of uncooked meat or liver and toxocariasis was reported, especially in adult patients. Future research on the potential source of infection, diagnosis, and treatment should be performed.

Human papilloma virus in retinoblastoma tissues from Korean patients

Purpose

Recent reports suggest the association of human papilloma virus (HPV) with retinoblastoma. This study was performed to elucidate whether HPV infection is related to retinoblastoma among Koreans.

Methods

A total of 54 cases diagnosed with retinoblastoma were enrolled from Seoul National University Children's Hospital and Seoul Metropolitan Government-Seoul National University Boramae Medical Center. Presence of human papilloma viral DNA was detected by in situ hybridization in formalin-fixed paraffin-embedded retinoblastoma tissues using both probes against high- and low risk HPV types.

Results

The mean age at diagnosis was 22.0 months (range, 1.1 to 98.0 months), and the mean age at enucleation was 27.8 months (range, 1.5 to 112.7 months) among the 54 patients with retinoblastoma. HPV was not detected in any of the retinoblastoma samples using either high risk or low risk HPV probes.

Conclusions

Our study, being the first study in the Korean population, proposes that HPV infection may have no causal relationship with retinoblastoma in Koreans.