Recent Advances in Clinical Applications of Imaging in Retinal Diseases.

Many diseases that cause visual impairment, as well as systemic conditions, manifest in the posterior segment of the eye. With the advent of high-speed, high-resolution, reliable, and noninvasive imaging techniques, ophthalmologists are becoming more dependent on ocular imaging for disease diagnosis, classification, and management in clinical practice. There are rapid advances on the indications of multimodal retinal imaging techniques, including the application of ultra-widefield fundus angiography, fundus autofluorescence, optical coherence tomography, as well as optical coherence tomography angiography. This review summarizes and highlights the clinical applications, latest indications, and interpretations of multimodal imaging in age-related macular degeneration, polypoidal choroidal vasculopathy, diabetic macular edema, central serous chorioretinopathy, diabetic retinopathy, retinal vein occlusion, and uveitis.

Evolution of Polypoidal Lesions after Treatment of Polypoidal Choroidal Vasculopathy.

Purpose: To evaluate the status and evolution of polypoidal lesions during the course of treatment of patients with symptomatic macular polypoidal choroidal vasculopathy (PCV). Design: Comparative cohort study of randomly selected patients from a multicenter, randomized controlled clinical trial. Participants: Thirty randomly selected patients from the EVEREST II study who were treated with combination ranibizumab and verteporfin photodynamic therapy (n = 15) or ranibizumab monotherapy (n = 15). Methods: All patients were randomized at baseline and treated with a standardized treatment protocol. Indocyanine green angiography (ICGA) images were graded at the central reading center at baseline and months 3, 6, 12, and 24. Polypoidal lesions present at baseline were overlaid on ICGA images at subsequent visits to determine if these remained perfused or had regressed completely. New polypoidal lesions occurring at subsequent visits were similarly tracked to detail the evolution of each polypoidal lesion. Main Outcome Measures: Complete polypoidal lesion regression over time. Results: Complete polypoidal lesion regression was higher in the combination therapy group compared with the monotherapy group at all visits (month 12, 12 of 15 patients [80%] vs. 5 of 14 patients [35.7%]; P = 0.016). Persistence of baseline polypoidal lesions was lower in the combination therapy group: 1 of 15 patients (6.7%) versus 7 of 14 patients (50%) in the monotherapy group at month 12. Recurrences of polypoidal lesions that had regressed completely at an earlier time point were uncommon: 0% in the combination therapy group and 1 patient each at months 6 and 12 in the monotherapy group. Fewer new polypoidal lesions (arising after the baseline visit) were found in the combination therapy group at all visits (combination therapy: 2 of 15 [13.3%] vs. monotherapy: 4 of 14 eyes [28.6%] at month 12). Total polypoidal lesion area was significantly smaller in the combination therapy group compared with the monotherapy group throughout the study (0.013 mm2 vs. 0.110 mm2; P < 0.01 at month 12). Conclusions: Combination therapy was associated with higher rates of complete polypoidal lesion regression and fewer persistent polypoidal lesions compared with monotherapy. Closed polypoidal lesions rarely reopened, regardless of the treatment.

PREDICTORS AND IMPORTANCE OF COMPLETE POLYPOIDAL LESION REGRESSION IN THE EVEREST II STUDY: Predictors of Polyp Regression in Polypoidal Choroidal Vasculopathy.

PURPOSE: To evaluate the predictors of complete polypoidal lesion regression (CPREG) in polypoidal choroidal vasculopathy. METHODS: Post hoc analysis of EVEREST II-a 24-month, multicenter, randomized, controlled clinical trial of 322 patients with polypoidal choroidal vasculopathy, randomized to receive ranibizumab with or without photodynamic therapy. Images of indocyanine green angiography (ICGA) were graded by a central reading center. Multiple logistic regression analysis with significant baseline predictors then was conducted to assess adjusted odds ratios for CPREG at month (M) 12. RESULTS: Baseline ICGA characteristics were comparable between the treatment groups. Patients treated with combination therapy had higher odds of achieving CPREG at M12 (adjusted odds ratio = 4.64; 95% confidence interval, 2.85-7.55; P < 0.001) compared with those in the monotherapy group. Absence of polypoidal lesion pulsation on ICGA was also associated with CPREG at M12 (adjusted odds ratio = 2.62; 95% confidence interval, 1.32-5.21; P = 0.006). The presence of CPREG at M3 had higher odds of maintaining CPREG at M12 (adjusted odds ratio = 6.60; 95% confidence interval, 3.77-11.57; P < 0.001) compared with those with persistent polypoidal lesions. CONCLUSION: At M12, treatment with combination therapy was associated with higher probability of achieving CPREG than with ranibizumab monotherapy. The results contribute to the further understanding of the response of polypoidal lesions to treatment.

11C-Metomidate PET-CT versus adrenal vein sampling to subtype primary aldosteronism: a prospective clinical trial.

OBJECTIVE: Adrenal vein sampling (AVS) is recommended to subtype primary aldosteronism, but it is technically challenging. We compared 11C-Metomidate-PET-computed tomography (PET-CT) and AVS for subtyping of primary aldosteronism. METHODS: Patients with confirmed primary aldosteronism underwent both AVS and 11C-Metomidate PET-CT (post-dexamethasone). All results were reviewed at a multidisciplinary meeting to decide on final subtype diagnosis. Primary outcome was accuracy of PET versus AVS to diagnosis of unilateral primary aldosteronism based on post-surgical biochemical cure. Secondary outcome was accuracy of both tests to final subtype diagnosis. RESULTS: All 25 patients recruited underwent PET and successful AVS (100%). Final diagnosis was unilateral in 22 patients, bilateral in two and indeterminate in one due to discordant lateralization. Twenty patients with unilateral primary aldosteronism underwent surgery, with 100% complete biochemical success, and 75% complete/partial clinical success. For the primary outcome, sensitivity of PET was 80% [95% confidence interval (95% CI): 56.3-94.3] and AVS was 75% (95% CI: 50.9-91.3). For the secondary outcome, sensitivity and specificity of PET was 81.9% (95% CI: 59.7-94.8) and 100% (95% CI: 15.8-100), and AVS was 68.2% (95% CI: 45.1-86.1) and 100% (95% CI: 15.8-100), respectively. Twelve out of 20 (60%) patients had both PET and AVS lateralization, four (20%) PET-only, three (15%) AVS-only, while one patient did not lateralize on PET or AVS. Post-surgery outcomes did not differ between patients identified by either test. CONCLUSION: In our pilot study, 11C-Metomidate PET-CT performed comparably to AVS, and this should be validated in larger studies. PET identified patients with unilateral primary aldosteronism missed on AVS, and these tests could be used together to identify more patients with unilateral primary aldosteronism. VIDEO ABSTRACT: http://links.lww.com/HJH/B918.

Multicentre, randomised clinical trial comparing intravitreal aflibercept monotherapy versus aflibercept combined with reduced-fluence photodynamic therapy (RF-PDT) for the treatment of polypoidal choroidal vasculopathy.

PURPOSE: To compare the efficacy and safety of intravitreal aflibercept (IVA) monotherapy versus aflibercept combined with reduced-fluence photodynamic therapy (RF-PDT) (IVA+RF-PDT) for the treatment of polypoidal choroidal vasculopathy (PCV). METHODS AND ANALYSIS: Multicentred, double-masked, randomised controlled trial to compare the two treatment modalities. The primary outcome of the study is to compare the 52-week visual outcome of IVA versus IVA+RF PDT. One hundred and sixty treatment-naïve patients with macular PCV confirmed on indocyanine green angiography will be recruited from three centres in Singapore. Eligible patients will be randomised (1:1 ratio) into one of the following groups: IVA monotherapy group-aflibercept monotherapy with sham photodynamic therapy (n=80); combination group-aflibercept with RF-PDT (n=80). Following baseline visit, all patients will be monitored at 4 weekly intervals during which disease activity will be assessed based on best-corrected visual acuity (BCVA), ophthalmic examination findings, optical coherence tomography (OCT) and angiography where indicated. Eyes that meet protocol-specified retreatment criteria will receive IVA and sham/RF-PDT according to their randomisation group. Primary endpoint will be assessed as change in BCVA at week 52 from baseline. Secondary endpoints will include anatomical changes based on OCT and dye angiography as well as safety assessment. Additionally, we will be collecting optical coherence tomography angiography data prospectively for exploratory analysis. ETHICS AND DISSEMINATION: This study will be conducted in accordance with the ethical principles that have their origin in the Declaration of Helsinki and that are consistent with the ICH E6 guidelines of Good Clinical Practice and the applicable regulatory requirements. Approval from the SingHealth Centralised Institutional Review Board has been sought prior to commencement of the study. TRIAL REGISTRATION NUMBER: NCT03941587.

Comparison of Polypoidal Choroidal Vasculopathy Lesion Sizes Measured on Multicolor Imaging and Indocyanine Green Angiography.

Purpose: To evaluate the areas of lesion components of polypoidal choroidal vasculopathy (PCV) measured using multicolor imaging compared to indocyanine green angiography (ICGA). Methods: In a prospective study of 50 consecutive treatment-naïve PCV patients, multicolor imaging and ICGA were performed. The images were independently graded by reading center-certified retinal specialists to confirm the diagnosis of PCV and identify lesion components. The areas of the respective lesion components were compared. Results: The mean age of the participants was 67.8 years. PCV was diagnosed in 96% of eyes using multicolor imaging. The mean numbers of polypoidal lesions identified using ICGA and multicolor were 4.0 and 2.1, respectively (P < 0.001), with mean total polypoidal lesion areas of 0.32 mm2 versus 0.30 mm2 (P = 0.727). The area of the branching vascular network (BVN) on ICGA was 7.8 mm2 compared to 5.7 mm2 on multicolor imaging (P = 0.289). Patients with four or more polypoidal lesions on ICGA had larger differences in total lesion area between ICGA and multicolor imaging (4.07 vs. -0.70 mm2, p = 0.039). Those with total lesion area ≥ 2.0 mm2 on ICGA had larger differences in mean polypoidal lesion number compared to those with smaller areas (2.2 vs. 0.5; P = 0.026). Conclusions: Multicolor imaging is a useful, noninvasive adjunct for detecting PCV lesion components, revealing lesion areas similar to but generally smaller than those seen on ICGA. This is important to consider when making treatment decisions with different imaging modalities. Translational Relevance: New features seen on multicolor imaging can aid in the diagnosis and treatment of PCV.

Non-ICGA treatment criteria for Suboptimal Anti-VEGF Response for Polypoidal Choroidal Vasculopathy: APOIS PCV Workgroup Report 2.

PURPOSE: To develop and validate OCT and color fundus photography (CFP) criteria in differentiating polypoidal choroidal vasculopathy (PCV) from typical neovascular age-related macular degeneration (nAMD) in eyes with suboptimal response to anti-vascular endothelial growth factor (VEGF) monotherapy and to determine whether OCT alone can be used to guide photodynamic therapy (PDT) treatment. DESIGN: Clinical study evaluating diagnostic accuracy. PARTICIPANTS: Patients with nAMD who received 3-month anti-VEGF monotherapy but had persistent activity defined as subretinal fluid or intraretinal fluid at month 3 assessments. METHODS: In phase 1, international retina experts evaluated OCT and CFP of eyes with nAMD to identify the presence or absence of features due to PCV. The performance of individual and combinations of these features were compared with ICGA. In phase 2, these criteria were applied to an independent image set to assess generalizability. In a separate exercise, retinal experts drew proposed PDT treatment spots using only OCT and near-infrared (NIR) images in eyes with PCV and persistent activity. The location and size of proposed spot were compared with ICGA to determine the extent of coverage of polypoidal lesions (PLs) and branching neovascular network (BNN). MAIN OUTCOME MEASURES: Sensitivity and specificity of CFP and OCT criteria to differentiate PCV from nAMD and accuracy of coverage of OCT-guided PDT compared with ICGA. RESULTS: In eyes with persistent activity, the combination of 3 non-ICGA-based criteria (sharp-peaked pigment epithelial detachment [PED], subretinal pigment epithelium [RPE] ring-like lesion, and orange nodule) to detect PCV showed good agreement compared with ICGA, with an area under the receiver operating characteristic curve of 0.85. Validation using both an independent image set and assessors achieved an accuracy of 0.77. Compared with ICGA, the OCT-guided PDT treatment spot covered 100% of PL and 90% of the BNN. CONCLUSIONS: In nAMD eyes with persistent activity, OCT and CFP can differentiate PCV from typical nAMD, which may allow the option of adjunct PDT treatment. Furthermore, OCT alone can be used to plan adjunct PDT treatment without the need for ICGA, with consistent and complete coverage of PL.

RANIBIZUMAB WITH OR WITHOUT VERTEPORFIN PHOTODYNAMIC THERAPY FOR POLYPOIDAL CHOROIDAL VASCULOPATHY: Predictors of Visual and Anatomical Response in the EVEREST II Study.

PURPOSE: To evaluate the demographic and imaging factors at baseline and Month 3 (M3) that predict visual or anatomical responses at Month 12 (M12) in the EVEREST-II study for polypoidal choroidal vasculopathy. METHODS: Post-hoc analysis of 322 participants in the EVEREST-II study. Patient factors, best-corrected visual acuity (BCVA), treatment, and imaging parameters at baseline and M3 were evaluated with respect to outcomes at M12 using univariate and multivariable analysis. RESULTS: Younger age (P < 0.001) and lower baseline BCVA (P < 0.001) were associated with higher BCVA gains at M12. Smaller baseline polypoidal lesion area was associated with higher BCVA gains at M12 only in the ranibizumab monotherapy arm (P = 0.008). Central subfield thickness at M3, area of branching vascular network at M3, BCVA at M3, and age were associated with change in BCVA from M3 at M12. Higher odds of fluid-free retina at M12 were associated with lower baseline central subfield thickness (P = 0.006), treatment with combination therapy (baseline and M3 models; P < 0.001), and absence of subretinal fluid at M3 (P < 0.001). CONCLUSION: Several imaging parameters at baseline and M3 can predict treatment outcome. The interaction between treatment arm and total polypoidal lesion area suggests this feature may assist selecting between initial ranibizumab monotherapy or combination therapy.

Adolescent with facial swelling.

BackgroundA previously well 15-year-old girl presented with a 2-month history of facial swelling that progressively worsened to involve the neck. There was associated dyspnoea, orthopnoea, headache and throat discomfort. Two weeks before presentation, the patient had an episode of fever for 5 days. On examination, vital signs were within normal limits. Swelling, plethora and venous distension of the face and neck were apparent (figure 1).

Polypoidal Choroidal Vasculopathy: Consensus Nomenclature and Non-Indocyanine Green Angiograph Diagnostic Criteria from the Asia-Pacific Ocular Imaging Society PCV Workgroup.

PURPOSE: To develop consensus terminology in the setting of polypoidal choroidal vasculopathy (PCV) and to develop and validate a set of diagnostic criteria not requiring indocyanine green angiography (ICGA) for differentiating PCV from typical neovascular age-related macular degeneration (nAMD) based on a combination of OCT and color fundus photography findings. DESIGN: Evaluation of diagnostic test results. PARTICIPANTS: Panel of retina specialists. METHODS: As part of the Asia-Pacific Ocular Imaging Society, an international group of experts surveyed and discussed the published literature regarding the current nomenclature and lesion components for PCV, and proposed an updated consensus nomenclature that reflects our latest understanding based on imaging and histologic reports. The workgroup evaluated a set of diagnostic features based on OCT images and color fundus photographs for PCV that may distinguish it from typical nAMD and assessed the performance of individual and combinations of these non-ICGA features, aiming to propose a new set of diagnostic criteria that does not require the use of ICGA. The final recommendation was validated in 80 eyes from 2 additional cohorts. MAIN OUTCOME MEASURES: Consensus nomenclature system for PCV lesion components and non-ICGA-based criteria to differentiate PCV from typical nAMD. RESULTS: The workgroup recommended the terms polypoidal lesion and branching neovascular network for the 2 key lesion components in PCV. For the diagnosis of PCV, the combination of 3 OCT-based major criteria (sub-retinal pigment epithelium [RPE] ring-like lesion, en face OCT complex RPE elevation, and sharp-peaked PED) achieved an area under the receiver operating characteristic curve of 0.90. Validation of this new scheme in a separate subset 80 eyes achieved an accuracy of 82%. CONCLUSIONS: We propose updated terminology for PCV lesion components that better reflects the nature of these lesions and is based on international consensus. A set of practical diagnostic criteria applied easily to spectral-domain OCT results can be used for diagnosing PCV with high accuracy in clinical settings in which ICGA is not performed routinely.

Artificial intelligence for teleophthalmology-based diabetic retinopathy screening in a national programme: an economic analysis modelling study.

BACKGROUND: Deep learning is a novel machine learning technique that has been shown to be as effective as human graders in detecting diabetic retinopathy from fundus photographs. We used a cost-minimisation analysis to evaluate the potential savings of two deep learning approaches as compared with the current human assessment: a semi-automated deep learning model as a triage filter before secondary human assessment; and a fully automated deep learning model without human assessment. METHODS: In this economic analysis modelling study, using 39 006 consecutive patients with diabetes in a national diabetic retinopathy screening programme in Singapore in 2015, we used a decision tree model and TreeAge Pro to compare the actual cost of screening this cohort with human graders against the simulated cost for semi-automated and fully automated screening models. Model parameters included diabetic retinopathy prevalence rates, diabetic retinopathy screening costs under each screening model, cost of medical consultation, and diagnostic performance (ie, sensitivity and specificity). The primary outcome was total cost for each screening model. Deterministic sensitivity analyses were done to gauge the sensitivity of the results to key model assumptions. FINDINGS: From the health system perspective, the semi-automated screening model was the least expensive of the three models, at US$62 per patient per year. The fully automated model was $66 per patient per year, and the human assessment model was $77 per patient per year. The savings to the Singapore health system associated with switching to the semi-automated model are estimated to be $489 000, which is roughly 20% of the current annual screening cost. By 2050, Singapore is projected to have 1 million people with diabetes; at this time, the estimated annual savings would be $15 million. INTERPRETATION: This study provides a strong economic rationale for using deep learning systems as an assistive tool to screen for diabetic retinopathy. FUNDING: Ministry of Health, Singapore.

Predictors of persistent disease activity following anti-VEGF loading dose for nAMD patients in Singapore: the DIALS study.

BACKGROUND: To determine the frequency of persistent disease activity following 3 loading doses of anti- vascular endothelial growth factor (VEGF) agents, and the anatomic and demographic predictors of early persistent disease activity among patients with neovascular age-related macular degeneration (nAMD). METHODS: In a retrospective real-world cohort study, 281 consecutive patients with nAMD were reviewed at baseline and after 3 anti-VEGF injections for pre-defined indicators of disease activity. Optical coherence tomography (OCT) features such as subretinal fluid, intraretinal cysts and intraretinal fluid were assessed by reading-center certified graders. Multiple logistic regression was performed on demographic and anatomic factors. RESULTS: At month 3, 66.1% of patients had persistent disease activity. The best-corrected visual acuity (BCVA) improvement was 0.16 LogMAR for those with no disease activity compared to 0 for patients with persistent activity (p < 0.001). The significant risk factors for persistent activity at 3 months were male gender (odds ratio [OR] 0.54, 95% confidence interval [CI] 0.32-0.93, p = 0.025), intraretinal cysts at baseline (OR 2.95, 95% CI 1.67-5.20, p < 0.001) and subretinal fluid at baseline (OR 3.17, 95% CI 1.62-6.18, p = 0.002). At 3 months, 58% of patients had features of activity on OCT. Patients with intraretinal cysts and intraretinal fluid at baseline had worse BCVA at month 3 compared to patients without these OCT features (0.69 vs. 0.43, p < 0.001, and 0.62 vs. 0.43, p < 0.001, respectively). CONCLUSIONS: In a real-world study, 66.1% of nAMD patients have persistent disease activity after the initial loading dose, with poorer BCVA compared to those without. Baseline OCT features (intraretinal cysts and subretinal fluid) are useful predictors of persistent disease activity at month 3.

Comparison of Ranibizumab With or Without Verteporfin Photodynamic Therapy for Polypoidal Choroidal Vasculopathy: The EVEREST II Randomized Clinical Trial.

Importance: The 2-year efficacy and safety of combination therapy of ranibizumab administered together with verteporfin photodynamic therapy (vPDT) compared with ranibizumab monotherapy in participants with polypoidal choroidal vasculopathy (PCV) are unclear. Objective: To compare treatment outcomes of ranibizumab, 0.5 mg, plus prompt vPDT combination therapy with ranibizumab, 0.5 mg, monotherapy in participants with PCV for 24 months. Design, Setting, and Participants: This 24-month, phase IV, double-masked, multicenter, randomized clinical trial (EVEREST II) was conducted among Asian participants from August 7, 2013, to March 2, 2017, with symptomatic macular PCV confirmed using indocyanine green angiography. Interventions: Participants (N = 322) were randomized 1:1 to ranibizumab, 0.5 mg, plus vPDT (combination therapy group; n = 168) or ranibizumab, 0.5 mg, plus sham PDT (monotherapy group; n = 154). All participants received 3 consecutive monthly ranibizumab injections, followed by a pro re nata regimen. Participants also received vPDT (combination group) or sham PDT (monotherapy group) on day 1, followed by a pro re nata regimen based on the presence of active polypoidal lesions. Main Outcomes and Measures: Evaluation of combination therapy vs monotherapy at 24 months in key clinical outcomes, treatment exposure, and safety. Polypoidal lesion regression was defined as the absence of indocyanine green hyperfluorescence of polypoidal lesions. Results: Among 322 participants (mean [SD] age, 68.1 [8.8] years; 225 [69.9%] male), the adjusted mean best-corrected visual acuity (BCVA) gains at month 24 were 9.6 letters in the combination therapy group and 5.5 letters in the monotherapy group (mean difference, 4.1 letters; 95% CI, 1.0-7.2 letters; P = .005), demonstrating that combination therapy was superior to monotherapy by the BCVA change from baseline to month 24. Combination therapy was superior to monotherapy in terms of complete polypoidal lesion regression at month 24 (81 of 143 [56.6%] vs 23 of 86 [26.7%] participants; P < .001). Participants in the combination group received fewer ranibizumab injections (median, 6.0 [interquartile range (IQR), 4.0-11.0]) than the monotherapy group (median, 12.0 [IQR, 7.0-17.0]) up to month 24. The combination group required a median of 2.0 (IQR, 1.0-3.0) vPDT treatments for 24 months, with 75 of 168 participants (44.6%) requiring only 1 vPDT treatment. Conclusions and Relevance: The 24-month data findings confirm that ranibizumab therapy, given as monotherapy or in combination with vPDT, is efficacious and safe for treatment of PCV. Combination therapy with vPDT added to ranibizumab achieved superior BCVA gain, increased odds of complete polypoidal lesion regression, and fewer treatment episodes compared with ranibizumab monotherapy. Trial Registration: ClinicalTrials.gov Identifier: NCT01846273.

Comparing efficacy of reduced-fluence and standard-fluence photodynamic therapy in the treatment of polypoidal choroidal vasculopathy.

BACKGROUND: The EVEREST II study reported superior polyp closure rates and visual outcomes using combination standard photodynamic therapy (PDT) with intravitreal ranibizumab in the treatment of polypoidal choroidal vasculopathy (PCV). The optimal PDT protocol remains controversial and it is postulated that less intensive PDT strategies may reduce complications. We aimed to compare the efficacy of reduced and standard-fluence PDT. METHODS: Case-control review of 38 consecutive PDT-naïve macular PCV patients who underwent verteporfin PDT using one of two PDT regimens at a tertiary referral centre in an Asian population. Comparison of outcomes between standard-fluence PDT (light dose, 50 J/cm2; dose rate, 600 mW/cm2; wavelength, 689 nm PDT applied to the treatment eye for 83 s) and reduced-fluence PDT (light dose, 25 J/cm2; dose rate, 600 mW/cm2; wavelength, 689 nm PDT applied to the treatment eye for 42 s). Primary outcome measure was best corrected LogMAR visual acuity (VA). Secondary outcome measures included OCT measurements such as central retinal thickness (CRT), height of subfoveal sub-retinal fluid (SRF), central choroid thickness (CCT), mean number of PDT treatments needed, mean number of anti-VEGF injections needed, polyp closure and recurrence rates. RESULTS: Of these 38 eyes of 38 patients, an equal number of eyes (19 in each arm) were treated with standard-fluence and reduced-fluence PDT. Mean letter gain at 12 months for the standard-fluence group was 6.0 compared to 4.3 letters for the reduced-fluence group (p = 0.61). Similar results were observed at all time points. There was no statistically significant difference between the retinal and choroidal anatomical OCT outcomes, rates of polyp closure and recurrences between the two PDT regimens. CONCLUSIONS: Reduced-fluence PDT was comparable to standard-fluence PDT in the treatment of PCV in terms of visual gains, clinical and anatomical OCT outcomes.

Use of smartphones for detecting diabetic retinopathy: a protocol for a scoping review of diagnostic test accuracy studies.

INTRODUCTION: Diabetic retinopathy (DR) is a common microvascular complication of diabetes mellitus and the leading cause of impaired vision in adults worldwide. Early detection and treatment for DR could improve patient outcomes. Traditional methods of detecting DR include the gold standard Early Treatment Diabetic Retinopathy Study seven standard fields fundus photography, ophthalmoscopy and slit-lamp biomicroscopy. These modalities can be expensive, difficult to access and require involvement of specialised healthcare professionals. With the development of mobile phone technology, there is a growing interest in their use for DR identification as this approach is potentially more affordable, accessible and easier to use. Smartphones can be employed in a variety of ways for ophthalmoscopy including the use of smartphone camera, various attachments and artificial intelligence for obtaining and grading of retinal images. The aim of this scoping review is to determine the diagnostic test accuracy of various smartphone ophthalmoscopy approaches for detecting DR in diabetic patients. METHODS AND ANALYSIS: We will perform an electronic search of MEDLINE, Embase and Cochrane Library for literature published from 2000 onwards. Two reviewers will independently analyse studies for eligibility and assess study quality using the QUADAS-2 tool. Data for a 2⨉2 contingency table will be extracted. If possible, we will pool sensitivity and specificity data using the random-effects model and construct a summary receiver operating characteristic curve. In case of high heterogeneity, we will present the findings narratively. Subgroup analysis and sensitivity analysis will be performed where appropriate. ETHICS AND DISSEMINATION: This scoping review aims to provide an overview of smartphone ophthalmoscopy in DR identification. It will present findings on the accuracy of smartphone ophthalmoscopy in detecting DR, identify gaps in the literature and provide recommendations for future research. This review does not require ethical approval as we will not collect primary data.

Current Status and Growth of Nuclear Theranostics in Singapore.

The concept of theranostics, where individual patient-level biological information is used to choose the optimal therapy for that individual, has become more popular in the modern era of 'personalised' medicine. With the growth of theranostics, nuclear medicine as a specialty is uniquely poised to grow along with the ever-increasing number of concepts combining imaging and therapy. This special report summarises the status and growth of Theranostic Nuclear Medicine in Singapore. We will cover our experience with the use of radioiodine, radioiodinated metaiodobenzylguanidine, peptide receptor radionuclide therapy, prostate specific membrane antigen radioligand therapy, radium-223 and yttrium-90 selective internal radiation therapy. We also include a section on our radiopharmacy laboratory, crucial to our implementation of theranostic principles. Radionuclide theranostics has seen tremendous growth and we hope to be able to grow alongside to continue to serve the patients in Singapore and in the region.

Multicolor Fundus Imaging of Polypoidal Choroidal Vasculopathy.

PURPOSE: Polypoidal choroidal vasculopathy (PCV) is a variant of neovascular age-related macular degeneration with distinct phenotypes, treatment, and visual prognosis. Multicolor imaging is a novel noninvasive imaging method that enables visualization of structures located at different layers of the retina and may be useful in detecting features of diseases. The features of PCV seen on multicolor imaging have not been studied. We aimed to describe the features of PCV detected using multicolor imaging and to compare these with standard color fundus photography (CFP). DESIGN: Hospital-based, cross-sectional study. PARTICIPANTS: Fifty consecutive treatment-naive patients diagnosed with PCV seen in a tertiary referral center. METHODS: Multimodal imaging was performed using standardized protocols, and included CFP, multicolor imaging, fluorescein angiography, and indocyanine green angiography (ICGA). The CFP and ICGA images were independently graded by reading center-certified retinal specialists to confirm the diagnosis of PCV and identify lesion components. The features of the lesion components seen on multicolor images were compared with those detected using CFP and ICGA. MAIN OUTCOME MEASURES: Frequency and features of lesions associated with PCV, specifically, polyps, branching vascular network (BVN), pigment epithelial detachments (PEDs), hemorrhages, and drusen. RESULTS: The mean age of the 50 participants was 67.9 years, and 60% were male. Polyps were most clearly seen on the infrared reflectance image and detected in 49 of 50 eyes (98%), appearing as dark gray oval lesions with distinct margins. On the multicolor composite images, polyps appeared as dark green oval lesions. The BVN appeared as mottled gray regions on infrared reflectance imaging and were seen less frequently compared with polyps (30/50 eyes, 60%). The margins of the BVN were less distinct compared with polyps. Other clinical features detected using multicolor imaging included PEDs (26%), subretinal hemorrhages (40%), and drusen (66%). CONCLUSIONS: Multicolor imaging is able to detect polypoidal lesions in most patients with PCV. The appearance of PCV lesions on multicolor imaging differs from standard CFP, although the location and shape of lesions correlate well with features seen on CFP and ICGA. Multicolor imaging is a useful, noninvasive adjunct to detect features suggestive of PCV, which may prompt definitive investigations such as ICGA.

EVEREST study report 4: Fluorescein angiography features predictive of polypoidal choroidal vasculopathy.

IMPORTANCE: It is important to identify features of polypoidal choroidal vasculopathy (PCV) that differentiate it from typical neovascular age-related macular degeneration (nAMD) on various imaging modalities, including fluorescein angiography (FA). BACKGROUND: PCV was thought to be indistinguishable from nAMD using FA alone. In real-world practice, indocyanine-green angiography may often be unavailable or contraindicated. DESIGN: Analysis of FA images from a prospective, multicentre study. PARTICIPANTS: Study images of both PCV and nAMD patients from the EVEREST study. METHODS: FA features at baseline were independently graded by masked graders (fellowship-trained ophthalmologists) using standardized diagnostic algorithms. MAIN OUTCOME MEASURES: Predictive indicators (sensitivity, specificity, positive and negative predictive values) for PCV. RESULTS: Of the 95 patients screened, 61 had PCV. Of the 34 screening failures, 15 were diagnosed as nAMD. Hyperfluorescent nodules on FA were observed in 80% of patients with PCV vs 20% with nAMD (P < 0.001). Blocked fluorescence on FA, which corresponded to the presence of subretinal haemorrhage, occurred more frequently among patients with PCV vs nAMD (61.7% vs 13.3%, P = 0.001). Similarly, the leakage characteristic of occult choroidal neovascularization occurred more frequently among patients with PCV vs nAMD (95.0% vs 73.3%, P = 0.026). The positive predictive value for PCV was 94.1% for hyperfluorescent nodules, 94.9% for blocked fluorescence, 83.8% for occult choroidal neovascularization and 82.0% for pigment epithelial detachment. CONCLUSIONS AND RELEVANCE: This study demonstrated that certain FA features can be predictive of PCV and may be considered as an indication for retina specialists to perform indocyanine green angiography as confirmatory test.