Eliminating Visual Acuity and Dilated Fundus Examinations Improves Cost Efficiency of Performing Optical Coherence Tomogrpahy-Guided Intravitreal Injections

A Systematic Prospective Comparison of Fluid Volume Evaluation across OCT Devices Used in Clinical Practice

Objective

Treatment decisions in neovascular age-related macular degeneration (nAMD) are mainly based on subjective evaluation of OCT. The purpose of this cross-sectional study was to provide a comparison of qualitative and quantitative differences between OCT devices in a systematic manner.

Design

Prospective, cross-sectional study.

Subjects

One hundred sixty OCT volumes, 40 eyes of 40 patients with nAMD.

Methods

Patients from clinical practice were imaged with 4 different OCT devices during one visit: (1) Spectralis Heidelberg; (2) Cirrus; (3) Topcon Maestro2; and (4) Topcon Triton. Intraretinal fluid (IRF), subretinal fluid (SRF), and pigment epithelial detachment (PED) were manually annotated in all cubes by trained human experts to establish fluid measurements based on expert-reader annotations. Intraretinal fluid, SRF, and PED volume were quantified in nanoliters (nL). Bland-Altman plots were created to analyze the agreement of measurements in the central 1 and 6 mm. The Friedman test was performed to test for significant differences in the central 1, 3, and 6 mm.

Main Outcome Measures

Intraretinal fluid, SRF, and PED volume.

Results

In the central 6 mm, there was a trend toward higher IRF and PED volumes in Spectralis images compared with the other devices and no differences in SRF volume. In the central 1 mm, the standard deviation of the differences ranged from ± 3 nL to ± 6 nL for IRF, from ± 3 nL to ± 4 nL for SRF, and from ± 7 nL to ± 10 nL for PED in all pairwise comparisons. Manually annotated IRF and SRF volumes showed no significant differences in the central 1 mm.

Conclusions

Fluid volume quantification achieved excellent reliability in all 3 retinal compartments on images obtained from 4 OCT devices, particularly for clinically relevant IRF and SRF values. Although fluid volume quantification is reliable in all 4 OCT devices, switching OCT devices might lead to deviating fluid volume measurements with higher agreement in the central 1 mm compared with the central 6 mm, with highest agreement for SRF volume in the central 1 mm. Understanding device-dependent differences is essential for expanding the interpretation and implementation of pixel-wise fluid volume measurements in clinical practice and in clinical trials.

Financial Disclosures

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Relative yield of retinal imaging versus clinical exam in following neovascular exudative age related macular degeneration

PURPOSE

To compare therapeutic decisions between 3 diagnostic protocols and to assess the need for in-person physical doctor-patient encounter in follow up and treatment of neovascular exudative age-related macular degeneration (AMD).

METHODS

Analysis of 88 eyes of 88 unique patients with neovascular AMD who were routinely followed at our medical retina clinic. A retinal specialist reviewed all images in advance and wrote his decisions. He later attended an in-person encounters with all patients and documented his decisions. Masking was done by not exposing any identifying information to the specialist and by randomizing patient's images order before the in-person encounter. Therapeutic decisions regarding intravitreal injections intervals and agent selection were made based on three protocols: (1) optic coherence tomography (OCT); (2) OCT/Ultra-widefield (UWF) color image; (3) OCT/UWF/full clinical exam. Visual acuity (VA) was incorporated into all protocols.

RESULTS

We found an agreement of 93% between those protocols regarding the intervals of injections, and of 100% regarding injection agent selection. When comparing OCT, OCT/UWF and OCT/UWF/clinical exam guided decision making, there were no discrepancies between OCT and OCT/UWF. There were 6 out of 88 discrepancies (7%) between OCT/UWF and OCT/UWF/clinical exam. Of those 6 discrepancies, all were regarding intervals (Bland-Altman bias = - 0.2386). All discrepancies between OCT/UWF and OCT/UWF/Clinical exam were due to patients' preferences, socioeconomic issues and fellow eye considerations, addressed during the face-to-face encounter with patients. Physical examination itself did not affect decision making.

CONCLUSIONS

Neovascular exudative AMD follow up and treatment decisions can be guided by VA and OCT, with UWF adding important information regarding macula and peripheral retina, but rarely affecting decision making. However, decision making may also be driven by patients' preferences and other considerations that are being made only during the face-to-face visit and discussion. Thus, every approach supporting imaging only decision making, must take these factors into account.

Assessing Change in Exudative Age-Related Macular Degeneration With Macular Thickness Maps as a Surrogate Strategy for Remote Patient Monitoring

PURPOSE

To determine if macular thickness maps (MTMs) are sufficient to guide management of eyes with exudative age-related macular degeneration (eAMD), we compared the ability to detect change using MTMs with the ability to detect change using the entire optical coherence tomography (OCT) scan in patients undergoing therapy.

DESIGN

Retrospective, comparative diagnostic analysis.

METHODS

Patients with eAMD were imaged using macula-centered 6 × 6-mm OCT scans (CIRRUS HD-OCT 5000; Zeiss). In each case, graders were asked to determine if there were changes that warranted a full clinical assessment after viewing 2 consecutive scans using one of 3 different imaging strategies: MTMs alone, individual foveal-centered B scans alone, or 5 macular B scans including the foveal-centered B scan. Graders were told the 2 scans were taken 2 weeks apart. The consensus ground truth was reached by the graders using a CIRRUS review station to evaluate all the information contained within the OCT scans.

RESULTS

A total of 53 eyes were included in this study with 1385 imaging sessions. The Fleiss kappa was highest when graders were given MTMs alone compared with the ground truth. When the averages of all 5 graders were compared with the ground truth, the MTMs alone showed the highest level of agreement (90.05%, SD 0.78%) followed by the central B scans (87.87%, SD 1.59%) and the 5-B scan method (86.512%, SD 0.64%).

CONCLUSION

MTMs alone provide sufficient information to easily identify recurrent exudation in patients with eAMD, and these maps may be all that is needed for remote monitoring.

Clinical outcome using a modified treat-and-extend protocol for neovascular age-related macular degeneration

AIM

To compare outcome between patients treated using a modified treat-and-extend (mT&E) protocol and patients treated using a conventional T&E protocol.

METHODS

A retrospective cohort study of two groups of treatment-naïve neovascular age-related macular degeneration patients within a single centre were evaluated. One group treated using the conventional T&E protocol, with visual acuity, dilated fundus examination (DFE) and optical coherence tomography (OCT) performed at each visit. The second group treated using the mT&E protocol in which visual acuity and DFE were performed only every three visits. The main outcome measures were time spent per clinical visit, visual and anatomical outcomes measured for 36 months.

RESULTS

The T&E and mT&E groups included 135 eyes in 116 patients and 119 eyes in 94 patients, respectively, with similar baseline characteristics. At 36 months, the number of injections administered (7.9±2.9 vs 8.1±2.3 injections, respectively; p=0.55), the percentage of eyes that gained ≥15 Early Treatment for Diabetic Retinopathy Study (ETDRS) letters (23% vs 25.2%, respectively; p=0.39) and the percentage of eyes that lost ≥15 ETDRS letters (21.5% vs 17.7%; p=0.43, respectively) were similar between the T&E and mT&E groups. However, waiting and contact time were reduced during the OCT-only visits compared with the full visits, with an average of 41 min saved per patient encounter.

CONCLUSIONS

Both protocols yielded similar visual and anatomical outcomes. However, the mT&E protocol reduced the number of full visits, with considerably less time spent at the clinic.

A Caveat about Financial Incentives for Anti-Vascular Endothelial Growth Factor Therapy for Diabetic Retinopathy

PURPOSE

To highlight the financial incentive to the physician of choosing an intravitreal anti-VEGF based strategy for treatment of non-proliferative and proliferative diabetic retinopathy and its possible risks to the patient and costs to the healthcare system.

DESIGN

Perspective, with retrospective cost and profit analysis METHODS: Review and synthesis of selected literature on the treatment of diabetic retinopathy, with interpretation of activity- and time-based costing of an intravitreal aflibercept strategy for diabetic retinopathy. Data from the DRCR Retina Network Protocols W and AB and from the PANORAMA trial are used to illustrate the potential financial incentive underlying such a treatment strategy.

RESULTS

Physician treatment algorithms for diabetic vitreous hemorrhage and non-proliferative diabetic retinopathy may be influenced by the substantial financial incentives intravitreal aflibercept strategies present despite functional equivalence with alternative, less profitable, strategies. For example, pursuing an intravitreal aflibercept based strategy for diabetic vitreous hemorrhage presents a 76% increased profit over pars plana vitrectomy with laser, with equivalent functional outcomes. For non-proliferative diabetic retinopathy, preventative aflibercept injections represent a potential 414% increase in profit over observation and an increased cost of $12164 to $17542 over two years per patient, with no improvement in visual function. These findings demonstrate that there may be misaligned financial incentives in the management of diabetic retinopathy.

CONCLUSIONS

While anti-VEGF therapy is a useful tool in the management of proliferative diabetic retinopathy and diabetic macular edema, we believe physicians should avoid overreliance on anti-VEGF injections in the treatment of diabetic retinopathy. Retina specialists should be cognizant of the limitations, costs and risks of anti-VEGF monotherapy and prophylactic therapy, and of the imperative to avoid bias towards financially remunerative practice patterns when equally effective alternatives exist.

Personalized treatment supported by automated quantitative fluid analysis in active neovascular age-related macular degeneration (nAMD)-a phase III, prospective, multicentre, randomized study: design and methods

INTRODUCTION

In neovascular age-related macular degeneration (nAMD) the exact amount of fluid and its location on optical coherence tomography (OCT) have been defined as crucial biomarkers for disease activity and therapeutic decisions. Yet in the absence of quantitative evaluation tools, real-world care outcomes are disappointing. Artificial intelligence (AI) offers a practical option for clinicians to enhance point-of-care management by analysing OCT volumes in a short time. In this protocol we present the prospective implementation of an AI-algorithm providing automated real-time fluid quantifications in a clinical real-world setting.

METHODS

This is a prospective, multicentre, randomized (1:1) and double masked phase III clinical trial. Two-hundred-ninety patients with active nAMD will be randomized between a study arm using AI-supported fluid quantifications and another arm using conventional qualitative assessments, i.e. state-of-the-art disease management. The primary outcome is defined as the mean number of injections over 1 year. Change in BCVA is defined as a secondary outcome.

DISCUSSION

Automated measurement of fluid volumes in all retinal compartments such as intraretinal fluid (IRF), and subretinal fluid (SRF) will serve as an objective tool for clinical investigators on which to base retreatment decisions. Compared to qualitative fluid assessment, retreatment decisions will be plausible and less prone to error or large variability. The underlying hypothesis is that fluid should be treated, while residual persistent or stable amounts of fluid may not benefit from further therapy. Reducing injection numbers without diminishing the visual benefit will increase overall patient safety and relieve the burden for healthcare providers.

TRIAL-REGISTRATION

EudraCT-Number: 2019-003133-42.

TREATMENT DEFERRAL DURING COVID-19 LOCKDOWN: Functional and Anatomical Impact on Patients With Neovascular Age-Related Macular Degeneration

PURPOSE

To investigate the visual and anatomical impact of intravitreal injection treatment deferral because of the COVID-19 lockdown on patients affected by neovascular age-related macular degeneration.

METHODS

We retrospectively reviewed 314 patients (394 eyes) who were scheduled to receive the impact of intravitreal injections during the Swiss lockdown. We compared patients who continued to receive scheduled impact of intravitreal treatment without clinical consultation (Group Continue ‟C"; n = 215) and patients for whom the impact of intravitreal treatment was completely deferred (Group Stop, ‟S"; n = 179). Functional and anatomical parameters were collected at four time points before and after the lockdown.

RESULTS

In Group C, the visual acuity at baseline and after the lockdown did not differ significantly. In Group S, the visual acuity deteriorated significantly compared with baseline and then improved slightly after the resumption of treatment, but it did not recover to baseline values. The mean central subfield thickness remained stable in Group C, whereas it increased in Group S and then returned to prelockdown values after the resumption of treatment.

CONCLUSION

An "injection-only" approach was effective in managing patients with neovascular age-related macular degeneration during the pandemic lockdown, whereas patients who deferred their scheduled treatment showed partially irreversible deterioration of visual function. We recommend treatment continuation in patients with neovascular age-related macular degeneration during a lockdown.

Additive value of a face-to-face visit to virtual remote decision in patients with neovascular age-related macular degeneration

INTRODUCTION

The increasing high prevalence of neovascular age-related macular degeneration (nvAMD) in the aging population combined with the need for frequent monitoring and treatment for many years, especially in the COVID19 era, raises the need to establish an effective, reliable and safe follow up and treatment model. This study evaluates the difference in treatment decisions comparing between the gold standard face-to-face clinical examination and virtual evaluation approach based only on visual acuity (VA) and optical coherence tomography (OCT) scans without clinical fundoscopic examination in neovascular age-related macular degeneration patients.

METHODS

Single center retrospective cohort study who compared an original 'face-to-face' visit treatment decision regarding the need for anti-vascular endothelial growth factor (anti-VEGF) drug, interval, and treatment regimen based on routine VA, spectral domain -OCT imaging and dilated fundus examination (DFE) to two 'virtual' treatment decisions based on evaluation of OCT scans and previous medical records before and after revealing VA data on the same nvAMD patients eyes.

RESULTS

169 eyes of 114 patients were included in the study. 49 patients (43%) suffered from bilateral nvAMD and had both eyes included in the study. Agreement between the "face-to-face visit treatment decision" and "virtual treatment decision" was noted in 74.6% and 71.6% eyes before and after revealing the patient's visual acuity in the study visit, respectively.

CONCLUSIONS

Virtual evaluation results in similar treatment decisions for nvAMD patients compared to standard face-to-face clinical examination.

Quantitative assessment of retinal fluid in neovascular age-related macular degeneration under anti-VEGF therapy

The retinal world has been revolutionized by optical coherence tomography (OCT) and anti-vascular endothelial growth factor (VEGF) therapy. The numbers of intravitreal injections are on a constant rise and management in neovascular age-related macular degeneration (nAMD) is mainly driven by the qualitative assessment of macular fluid as detected on OCT scans. The presence of macular fluid, particularly subretinal fluid (SRF) and intraretinal fluid (IRF), has been used to trigger re-treatments in clinical trials and the real world. However, large discrepancies can be found between the evaluations of different readers or experts and especially small amounts of macular fluid might be missed during this process. Pixel-wise detection of macular fluid uses an entire OCT volume to calculate exact volumes of retinal fluid. While manual annotations of such pixel-wise fluid detection are unfeasible in a clinical setting, artificial intelligence (AI) is able to overcome this hurdle by providing real-time results of macular fluid in different retinal compartments. Quantitative fluid assessments have been used for various post hoc analyses of randomized controlled trials, providing novel insights into anti-VEGF treatment regimens. Nonetheless, the application of AI-algorithms in a prospective patient care setting is still limited. In this review, we discuss the use of quantitative fluid assessment in nAMD during anti-VEGF therapy and provide an outlook to novel forms of patient care with the support of AI quantifications.

AI-based monitoring of retinal fluid in disease activity and under therapy

Retinal fluid as the major biomarker in exudative macular disease is accurately visualized by high-resolution three-dimensional optical coherence tomography (OCT), which is used world-wide as a diagnostic gold standard largely replacing clinical examination. Artificial intelligence (AI) with its capability to objectively identify, localize and quantify fluid introduces fully automated tools into OCT imaging for personalized disease management. Deep learning performance has already proven superior to human experts, including physicians and certified readers, in terms of accuracy and speed. Reproducible measurement of retinal fluid relies on precise AI-based segmentation methods that assign a label to each OCT voxel denoting its fluid type such as intraretinal fluid (IRF) and subretinal fluid (SRF) or pigment epithelial detachment (PED) and its location within the central 1-, 3- and 6-mm macular area. Such reliable analysis is most relevant to reflect differences in pathophysiological mechanisms and impacts on retinal function, and the dynamics of fluid resolution during therapy with different regimens and substances. Yet, an in-depth understanding of the mode of action of supervised and unsupervised learning, the functionality of a convolutional neural net (CNN) and various network architectures is needed. Greater insight regarding adequate methods for performance, validation assessment, and device- and scanning-pattern-dependent variations is necessary to empower ophthalmologists to become qualified AI users. Fluid/function correlation can lead to a better definition of valid fluid variables relevant for optimal outcomes on an individual and a population level. AI-based fluid analysis opens the way for precision medicine in real-world practice of the leading retinal diseases of modern times.

Current status of home monitoring technology for age-related macular degeneration

PURPOSE OF REVIEW

Evidence suggests that patients present with exudative age-related macular degeneration (AMD) in a delayed fashion. Increased lesion size associated with this delay directly impacts visual acuity. Upon treatment initiation, patients are monitored largely with optical coherence tomography (OCT) technology to determine the need for treatment. Home-monitoring systems using preferential hyperacuity perimetry (PHP) and OCT may optimize management.

RECENT FINDINGS

Comparison of Age-related Macular Degeneration Treatment Trials study and American Academy of Ophthalmology's Intelligent Research in Sight registry data suggest smaller lesion size and better visual acuity upon choroidal neovascularization (CNV) capture are associated with better final visual acuity with therapy. The HOME study and recent PHP-based ForeseeHome data indicate that this modality leads to earlier detection of CNV. Results of a real-world data analysis demonstrate 82% retention of ≥20/40 vision with median visual acuity of 20/40 at time of CNV detection using PHP home-monitoring. Home OCT data suggests excellent patient useability, with >90% of patients obtaining analyzable images. The Notal OCT Analyzer demonstrates superiority over human interpreters regarding the ability to detect intraretinal and subretinal fluid (82% vs. 47% sensitivity).

SUMMARY

PHP may improve treatment outcomes for exudative AMD by allowing for earlier detection of lesions. Home OCT platforms could allow for more convenient monitoring of patients undergoing treatment for exudative AMD and better enable true PRN models.

Revisiting the Utility of Dilated Fundus Exams in Patients with Neovascular Age-Related Macular Degeneration Receiving Regular Intravitreal Injections

Patients receiving regular anti-vascular endothelial growth factor (anti-VEGF) intravitreal injections for neovascular age-related macular degeneration (nAMD) routinely undergo dilated fundus examination (DFE) at each visit. In this paper, we review the current evidence on the utility of DFE in guiding treatment of established patients with nAMD and discuss novel treatment algorithms that defer DFE assessments with the advent of optical coherence tomography (OCT). We also debate on the value of DFE in the current sanitary context of COVID-19 and highlight important clinical scenarios where it must be performed.