MULTIMODAL IMAGING OF EARLY STAGE 1 TYPE 3 NEOVASCULARIZATION WITH SIMULTANEOUS EYE-TRACKED SPECTRAL-DOMAIN OPTICAL COHERENCE TOMOGRAPHY AND HIGH-SPEED REAL-TIME ANGIOGRAPHY

Review of type 3 macular neovascularization in age-related macular degeneration: no DRAMA (Deep Retinal Age-related Microvascular Anomalies)

Type 3 macular neovascularization (MNV) is a unique form of neovascular age-related macular degeneration (AMD) that presents distinct pathogenetic features, clinical manifestations, and prognostic considerations when compared to types 1 and 2 MNV. Insights gained from clinicopathological correlations, bridging in vivo examination techniques with ex vivo histological analysis, have significantly enhanced our comprehension of this MNV phenotype, shaped current management strategies and influenced future directions for therapeutics. The particularities of type 3 MNV, which may largely stem from its origin from the retinal vasculature, are critically important for predicting the disease course. Our current understanding suggests that type 3 MNV occurs in response to retinal pigment epithelium (RPE) disruption and photoreceptor loss when neovessels originating from the deep capillary plexus are accompanied by activated Müller glia as they infiltrate sub-retinal pigment epithelium basal laminar deposits. Dysregulation of angiogenic and angiostatic factors are thought to play a key role in its pathogenesis. The prognosis for type 3 MNV is likely bilateral involvement and progression towards macular atrophy. It may be imperative for practitioners to distinguish type 3 MNV from other mimicking pathologies such as intraretinal microvascular anomalies, which are also part of the type 3 disease spectrum. For instance, deep retinal age-related microvascular anomalies (DRAMA) may present with similar features on multimodal imaging yet may necessitate distinct management protocols. Distinguishing between these conditions may be vital for implementing tailored treatment regimens and improving patient outcomes in the diverse landscape of AMD phenotypes in the future.

Detection of Macular Neovascularization in Eyes Presenting with Macular Edema using OCT Angiography and a Deep Learning Model

PURPOSE

To test the diagnostic performance of an artificial intelligence algorithm for detecting and segmenting macular neovascularization (MNV) with OCT and OCT angiography (OCTA) in eyes with macular edema from various diagnoses.

DESIGN

Prospective cross-sectional study.

PARTICIPANTS

Study participants with macular edema due to either treatment-naïve exudative age-related macular degeneration (AMD), diabetic macular edema (DME), or retinal vein occlusion (RVO).

METHODS

Study participants were imaged with macular 3 × 3-mm and 6 × 6-mm spectral-domain OCTA. Eyes with exudative AMD were required to have MNV in the central 3 × 3-mm area. A previously developed hybrid multitask convolutional neural network for MNV detection (aiMNV), and segmentation was applied to all images, regardless of image quality.

MAIN OUTCOME MEASURES

Sensitivity, specificity, positive predictive value, and negative predictive value of detecting MNV and intersection over union (IoU) score and F1 score for segmentation.

RESULTS

Of 114 eyes from 112 study participants, 56 eyes had MNV due to exudative AMD and 58 eyes with macular edema due to either DME or RVO. The 3 × 3-mm OCTA scans with aiMNV detected MNV with 96.4% sensitivity, 98.3% specificity, 98.2% positive predictive value, and 96.6% negative predictive value. For segmentation, the average IoU score was 0.947, and the F1 score was 0.973. The 6 × 6-mm scans performed well; however, sensitivity for MNV detection was lower than 3 × 3-mm scans due to lower scan sampling density.

CONCLUSIONS

This novel aiMNV algorithm can accurately detect and segment MNV in eyes with exudative AMD from a control group of eyes that present with macular edema from either DME or RVO. Higher scan sampling density improved the aiMNV sensitivity for MNV detection.

FINANCIAL DISCLOSURE(S)

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

Current Perspectives on Type 3 Macular Neovascularization due to Age-Related Macular Degeneration

BACKGROUND

The aim of this review was to systematically summarize the current knowledge on type 3 macular neovascularization (MNV3) in age-related macular degeneration (AMD).

SUMMARY

Recent histopathologic and multimodal imaging findings led to the consensus definition of the new term "type 3 macular neovascularization" in AMD. MNV3 originates in the deep vascular plexus as a neovascular process without connection with the retinal pigment epithelium in the initial stages. This type has numerous clinical and pathomorphologic features that separate it from the other two types of MNV in AMD. Besides, its frequency appears to be higher than previously thought. In optical coherence tomography (OCT), MNV3 can be classified into stages 1-3. Hyperreflective foci in the outer retina possibly represent a precursor lesion. In addition, MNV3 is characterized by a strong association with reticular pseudodrusen, a high rate of bilaterality, close associations with advanced age and arterial hypertension, decreased choroidal thickness, and decreased choriocapillaris flow signals. Data from latest anti-vascular endothelial growth factor studies in MNV3 suggest that the OCT biomarkers in intraretinal and subretinal fluids should be interpreted differently than in the other types. Additionally, data from MNV3 eyes should be analyzed separately, allowing optimal type-specific treatment strategies in the future.

KEY MESSAGES

This review highlights the need for accurate characterization of neovascular AMD lesions and an MNV type-specific approach, particularly for MNV3.

Pushing Retinal Imaging Forward: Innovations and Their Clinical Meaning - The 2022 Ophthalmologica Lecture

Retinal imaging has greatly expanded our understanding of various pathological conditions. This article presents a summary of the key points covered during the 2022 Ophthalmologica Lecture held at the Euretina Congress in Hamburg. The first part of the article focuses on the use of optical coherence tomography angiography to examine and comprehend the choroid in age-related macular degeneration (AMD). Subsequently, we delve into the discussion of the "postreceptor neuronal loss" theory in AMD, which was studied using en face structural optical coherence tomography (OCT). Following that, we explore pertinent findings obtained through cross-sectional OCT in retinal and optic nerve diseases, such as AMD, diabetic macular edema, pathologic myopia, central serous chorioretinopathy, and Leber's hereditary optic neuropathy.

Clinical Pathological Features and Current Animal Models of Type 3 Macular Neovascularization

Type 3 macular neovascularization (MNV3), or retinal angiomatous proliferation (RAP), is a distinct type of neovascular age-related macular degeneration (AMD), which is a leading cause of vision loss in older persons. During the past decade, systematic investigation into the clinical, multimodal imaging, and histopathological features and therapeutic outcomes has provided important new insight into this disease. These studies favor the retinal origin of MNV3 and suggest the involvement of retinal hypoxia, inflammation, von Hippel–Lindau (VHL)–hypoxia-inducible factor (HIF)–vascular endothelial growth factor (VEGF) pathway, and multiple cell types in the development and progression of MNV3. Several mouse models, including the recently built Rb/p107/Vhl triple knockout mouse model by our group, have induced many of the histological features of MNV3 and provided much insight into the underlying pathological mechanisms. These models have revealed the roles of retinal hypoxia, inflammation, lipid metabolism, VHL/HIF pathway, and retinoblastoma tumor suppressor (Rb)–E2F cell cycle pathway in the development of MNV3. This article will summarize the clinical, multimodal imaging, and pathological features of MNV3 and the diversity of animal models that exist for MNV3, as well as their strengths and limitations.

CHORIOCAPILLARIS FLOW IMPAIRMENT IN TYPE 3 MACULAR NEOVASCULARIZATION: A Quantitative Analysis Using Swept-Source Optical Coherence Tomography Angiography

PURPOSE

To quantitatively analyze choriocapillaris alterations using swept-source optical coherence tomography angiography in eyes presenting with Type 3 macular neovascularization (MNV) and to compare these alterations with eyes presenting with intermediate AMD (iAMD).

METHODS

Macular 3 × 3-mm swept-source optical coherence tomography angiography scans were retrospectively analyzed in eyes with Type 3 MNV and in eyes with iAMD. The choriocapillaris en face slabs were extracted from the swept-source optical coherence tomography angiography device after manual segmentation. En face choriocapillaris flow images were compensated with en face choriocapillaris structure images, followed by the Phansalkar local thresholding method using a window radius of 4 and 8 pixels. The percentage of flow deficits (FD%), the number, size, and total area of FDs were computed for comparison. A secondary analysis was performed in the four corners of the image to include equidistant regions in all eyes.

RESULTS

Twenty-six Type 3 MNV eyes of 21 patients and 26 iAMD eyes of 17 patients were included. Compared with iAMD eyes, eyes with Type 3 MNV displayed a higher FD% (41.37% ± 14.74 vs. 19.80% ± 9.63 using radius 4 pixels [P < 0.001]; 45.24% ± 11.9 vs. 26.63% ± 8.96 using radius 8 pixels [P < 0.001]). The average size of FDs was significantly larger in Type 3 MNV eyes compared with iAMD eyes (P < 0.001), whereas the number of FDs was significantly lower in Type 3 MNV compared with iAMD eyes (P < 0.001).

CONCLUSION

Type 3 MNV eyes present with increased choriocapillaris flow impairment compared with iAMD eyes. Reduced choriocapillaris perfusion may contribute to Type 3 MNV development and pathogenesis.

Longitudinal assessment of type 3 macular neovascularization using three-dimensional volume-rendering OCTA

OBJECTIVE

To investigate the evolution of treatment-naive type 3 macular neovascularization (MNV) undergoing anti-vascular endothelial growth factor (VEGF) treatment through volume rendered three-dimensional (3D) optical coherence tomography angiography (OCTA).

DESIGN

Retrospective observational study.

PARTICIPANTS

Patients with type 3 MNV and age-related macular degeneration (AMD).

METHODS

Included subjects had three loading injections of an anti-VEGF agent. The OCTA volume data at baseline and follow-up were processed with a previously published algorithm in order to obtain a volume-rendered representation of type 3 MNV. Progressive changes in type 3 lesions were analyzed via 3D OCTA volume rendering.

RESULTS

A total of 14 treatment-naive eyes with type 3 MNV from 11 AMD patients (7 females) were included. At both baseline and follow-up visits, a type 3 MNV complex was identifiable. Each complex was composed of a mean number of 2.5 ± 0.7 vascular branches at baseline and 1.4 ± 0.6 at the follow-up visit (p < 0.0001). The mean changes in central macular thickness and visual acuity were significantly correlated with modifications in the number of type 3 MNV branches (ρ = -0.533, p = 0.049, and ρ = -0.581, and p = 0.040, respectively).

CONCLUSIONS

This study demonstrated that type 3 lesions do not disappear completely after loading treatment, as indicated previously by histopathologic studies. Importantly, quantitative volume changes in type 3 lesions are directly associated with treatment response.

Multimodal Imaging to Detect in vivo Responses to Aflibercept Therapy in a Mouse Model of Type 3 Neovascularization

PURPOSE

The aim of this study was to characterize the response to aflibercept in a mouse model of type 3 neovascularization, the neoretinal vascularization (NRV) 2 mouse line.

METHODS

Twelve NRV2 mice were assigned to one of the following groups: (1) 6 mice were injected with aflibercept 3 µg/g at postnatal day (P) 15 ("aflibercept" group), and (2) the remaining 6 mice did not receive any treatment ("placebo" group). The mice were examined at P30 and P44.

RESULTS

The NRV mice's retinas were characterized by regions of depigmentation that were topographically associated with hyperfluorescent lesions seen on fluorescein angiography (FA) images. On optical coherence tomography images, intraretinal neovascularizations were visualized as hyperreflective lesions mainly localized within the outer plexiform and outer nuclear layers. The average number of intraretinal neovascular lesions visualized on FA at P30 was 5.0 ± 2.2 in the aflibercept group and 20.7 ± 2.4 in the placebo group (p < 0.0001). At P44, the average number of intraretinal lesions was still lower in the aflibercept group, although this difference was not statistically significant (p = 0.088).

CONCLUSION

Aflibercept therapy was effective in inhibiting pathologic angiogenesis in the NRV2 mouse model. However, the successive treatment washout resulted in an increase in the number of lesions.

OCT-A characterisation of recurrent type 3 macular neovascularisation

Purpose

To investigate optical coherence tomography angiography (OCT-A) findings in recurrent type 3 macular neovascularisation (MNV).

Methods

In this retrospective cohort study, consecutive patients with type 3 MNV secondary to age-related macular degeneration underwent OCT-A at three different time points: baseline, after anti-vascular endothelial growth factor treatment with complete resolution of the exudative signs (ie, non-exudative stage) and at the recurrence of exudation (ie, recurrence stage). Demographics and clinical findings were analysed, including OCT-A features of type 3 MNV recurrence.

Results

Twelve eyes (12 patients, mean age 78±7 years) were included. Using OCT-A, at baseline all type 3 MNVs showed the presence of detectable flow downgrowing from the deep vascular complex (DVC) to the retinal pigment epithelium (RPE)/sub-RPE space. 6/12 eyes (50%) showed anomalous flow under the RPE, while the other 6 eyes showed flow reaching the RPE without anomalous flow in the sub-RPE space. At the non-exudative stage (after treatment), BCVA and CMT significantly improved (p=0.004 and p=0.036), and flow inside the retinal lesions reduced; interestingly the connection to the RPE/sub-RPE space regressed. At the time of recurrence, all type 3 MNVs showed the presence of intra/sub-retinal exudation with restoration of the flow deepening from the DVC to the RPE/sub-RPE space.

Conclusions

Detectable flow deepening from the DVC to the RPE/sub-RPE space using OCT-A is mandatory to have a new exudation secondary to recurrent type 3 MNV. Early detection of type 3 MNV recurrence by OCT-A characterisation may prompt retreatment and potentially prevent progression to late stages of the disease.

Rotational Three-dimensional OCTA: a Notable New Imaging Tool to Characterize Type 3 Macular Neovascularization

This study explored whether rotational three-dimensional (3D) visualization of optical coherence tomography angiography (OCTA) volume data may yield valuable information regarding type 3 macular neovascularization (MNV). In this retrospective, cross-sectional study, we collected data from 15 eyes (13 patients) with treatment-naïve type 3 MNV in their post-nascent stage and age-related macular degeneration (AMD). Subjects were imaged with the SS-OCT system (PLEX Elite 9000, Carl Zeiss Meditec Inc., Dublin, CA, USA). The OCTA volume data were processed with a prototype volume projection removal algorithm and then analyzed using volumetric visualization techniques in order to obtain a 3D visualization of the region occupied by type 3 MNV. The two-dimensional and three-dimensional OCTA images were investigated. Mean ± SD age was 75.1 ± 7.4 years. BCVA was 0.42 ± 0.21 LogMAR in the study eyes. Considering the cohort of analyzed eyes, on rotational 3D OCTA images, a total of 35 neovascular lesions (vs 22 lesions detected on 2D OCTA images) rising from the deep vascular complex and variably spanning the outer retinal layers and eventually reaching the RPE/sub-RPE space were detected. Nine of 35 lesions had a saccular shape, while the remaining cases had a filiform shape. On rotational 3D OCTA images, these lesions were inclined on the three planes, instead of perpendicular to the RPE/Bruch’s membrane. In conclusion, this study used an algorithm to obtain rotational three-dimensional visualization of type 3 MNV. This approach seems to increase the detection rate for these lesions and to be useful to offer new insight into type 3 MNV.

Nascent Type 3 Neovascularization in Age-Related Macular Degeneration

PURPOSE

To describe the preclinical and very early stages of type 3 neovascularization using multimodal retinal imaging to expand our understanding of the pathogenesis of this disorder and potentially to prevent late treatment.

DESIGN

Retrospective cohort study.

PARTICIPANTS

Patients diagnosed with treatment-naïve type 3 neovascularization in the setting of age-related macular degeneration were identified at 4 retina referral centers. Inclusion criteria were: patients older than 55 years with at least 1 OCT and OCT angiography (OCTA) examination before the onset of clinically active type 3 neovascularization (i.e., preclinical stage).

METHODS

Patients underwent a complete ophthalmologic examination including at least OCT and OCTA at the baseline and preclinical stage examinations, and dye angiographies when available. Demographics and clinical findings were analyzed.

MAIN OUTCOME MEASURES

Description of multimodal imaging features of nascent type 3 neovascularization.

RESULTS

Fifteen eyes (15 patients; mean age, 83 ± 9 years) were included. At the baseline, mean BCVA was 0.32 ± 0.17 logarithm of the minimum angle of resolution and central macular thickness was 313 ± 50 μm. Preclinical (i.e., prebaseline) structural OCT illustrated the presence of intraretinal hyperreflective foci (HRF) at the site of type 3 neovascularization development in all patients. These foci were characterized by hyperfluorescence on dye angiography and by detectable flow on OCTA, identified with either the avascular slab (20%) or with both the deep retinal capillary plexus (DCP) and avascular slabs (80%). Typically, HRF with detectable flow on OCTA were characterized by the absence of intraretinal exudation (or very mild microcystic changes) until the lesion progressed from the DCP into the retinal pigment epithelium (RPE) and sub-RPE space. Of note, in 1 patient we observed the complete resolution of HRF despite the presence of OCTA flow and dye angiography hyperfluorescence detected at the preclinical stage examination.

CONCLUSIONS

Hyperreflective foci on structural OCT may represent early intraretinal neovascularization originating from the DCP, namely nascent type 3 neovascularization; these lesions can progress to active type 3 neovascularization or more rarely may regress without functional impairment. An advanced multimodal imaging approach is useful in detecting nascent type 3 lesions, which should be followed up carefully and treated as soon as possible if flow progresses to the RPE and sub-RPE space to prevent progression to late stages.

Retinal Angiomatous Proliferation: Multimodal Imaging Characteristics and Follow-up with Eye-Tracked Spectral Domain Optical Coherence Tomography of Precursor Lesions

Objectives:

To present the multimodal imaging characteristics of precursor retinal angiomatous proliferation (RAP) lesions and follow-up results with eye-tracked spectral-domain optical coherence tomography (SD-OCT).

Materials and Methods:

Six eyes of 6 patients aged 77.5±5.9 years diagnosed with precursor RAP lesion were included in this prospective observational case series. Best corrected visual acuity (BCVA) measurement and complete ophthalmologic examination were performed for all subjects, as well as fundus photography (FP), fundus autofluorescence (FAF), SD-OCT, fluorescein angiography (FA), indocyanine green angiography (ICGA), optical coherence tomography angiography (OCTA), and their long-term follow-up results are presented.

Results:

The mean BCVA was 0.8±0.16 (0.6-1) Snellen and the mean follow-up was 26.3±14.8 months. Images of the precursor RAP lesions demonstrated no specific findings on FP and FAF, showed focal hypofluorescent foci with no leakage on FA and IGA, and appeared as extrafoveal small, round, well-defined, hyperreflective foci typically located in the outer retinal layers on SD-OCT B-scans with high sampling density. OCTA demonstrated the precursor lesions as the deep capillary plexus abnormalities in 3 eyes. Two eyes progressed to stage 1 RAP during the follow-up period.

Conclusion:

This study defined the diagnostic characteristics and clinical course of precursor RAP lesions. Our findings highlight the importance of B-scans with high sampling density for the diagnosis of precursor lesions and using eye-tracking mode SD-OCT during follow-up.

NATURAL COURSE OF PATIENTS DISCONTINUING TREATMENT FOR AGE-RELATED MACULAR DEGENERATION AND FACTORS ASSOCIATED WITH VISUAL PROGNOSIS

PURPOSE

To evaluate the 24-month natural course of visual changes in patients discontinuing treatment despite persistent or recurrent fluid and factors predictive of visual prognosis.

METHODS

This retrospective, observational study included 35 patients (35 eyes) who initially received anti-vascular endothelial growth factor treatment for neovascular age-related macular degeneration (AMD), but discontinued treatment despite persistent or recurrent fluid. The best-corrected visual acuity (BCVA) at treatment discontinuation was determined and compared with the 24-month BCVA, which was then compared between polypoidal choroidal vasculopathy and other neovascular age-related macular degeneration subtypes. Baseline characteristics predictive of visual outcome and the degree of visual change were also analyzed.

RESULTS

The mean number of anti-vascular endothelial growth factor injections before treatment discontinuation was 4.0 ± 1.6. The mean logarithm of minimal angle of resolution of BCVA at treatment discontinuation and that at 24 months were 1.02 ± 0.20 (Snellen equivalents = 20/209) and 1.60 ± 0.56 (20/796), respectively (P < 0.001). The 24-month BCVA was not different between polypoidal choroidal vasculopathy and other neovascular age-related macular degeneration subtypes (P = 0.803). The type of fluid (intraretinal fluid vs. no intraretinal fluid) was predictive of 24-month BCVA (P = 0.004) and the degree of changes in BCVA (P = 0.043).

CONCLUSION

Marked deterioration in visual acuity was noted in patients discontinuing treatment, regardless of neovascular age-related macular degeneration subtypes. The presence of intraretinal fluid was associated with worse visual prognosis, suggesting that patients with intraretinal fluid should be strongly warned about their poor prognosis before they decide to discontinue treatment.

OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY CHANGES IN EARLY TYPE 3 NEOVASCULARIZATION AFTER ANTI-VASCULAR ENDOTHELIAL GROWTH FACTOR TREATMENT

PURPOSE

To investigate the morphologic changes on optical coherence tomography angiography (OCTA) of treatment-naive Type 3 neovascularization secondary to exudative age-related macular degeneration after 1 year of anti-vascular endothelial growth factor therapy.

METHODS

Consecutive patients diagnosed with treatment-naive early-stage Type 3 neovascularization were enrolled in this retrospective study. All patients underwent color fundus photographs/MultiColor (Heidelberg Engineering) imaging, fluorescein angiography, indocyanine green angiography, structural spectral domain OCT, and OCTA Optovue RTVue XR Avanti (Optovue) at baseline, and repeated OCTA and structural spectral domain OCT at Month 12. Qualitative analysis of the 3 × 3 OCTA examinations at baseline and Month 12 was then compared, to assess changes after anti-vascular endothelial growth factor therapy.

RESULTS

A total of 15 treatment-naive eyes of 15 consecutive patients were included in the analysis. At 12-month follow-up after pro-re-data anti-vascular endothelial growth factor therapy (5.75 ± 1.48 injections of ranibizumab, and injections of 6.33 ± 1.21 of aflibercept), OCTA demonstrated persistence of the deep capillary plexus abnormalities in 13/15 eyes. In the outer retina and choriocapillaris, the initial lesion became undetectable in 7/15 cases, accompanied by choriocapillaris atrophy. The abnormal vascular complex persisted in the form of a tuft-shaped lesion in the outer retinal segmentation in 9/15 eyes, which in the choriocapillaris segmentation was associated with sub-retinal pigment epithelium neovascularization in 8 cases.

CONCLUSION

Optical coherence tomography angiography showed that the tuft-shaped abnormal outer retinal lesion, frequently associated with a small clew-like flow signal in the choriocapillaris, after 1 year of anti-vascular endothelial growth factor therapy, either becomes undetectable or develops sub-retinal pigment epithelium neovascularization.

TYPE 3 NEOVASCULARIZATION IMAGED WITH CROSS-SECTIONAL AND EN FACE OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY

PURPOSE

To study the cross-sectional and en face optical coherence tomography angiography (OCTA) findings in Type 3 neovascularization (NV).

METHODS

Optical coherence tomography angiography imaging of 27 eyes of 23 patients with Type 3 NV was analyzed with 9 eyes having consecutive follow-up OCTA studies.

RESULTS

Type 3 NV appeared as a linear high-flow structure on cross-sectional OCTA corresponding to a high-flow tuft of vessels seen on en face OCTA. Cross-sectional OCTA seemed to enable the distinction between vascular and nonvascular intraretinal hyperreflective foci. Two patterns of flow were observed; Pattern 1 (11%): a flow signal confined to the neurosensory retina and Pattern 2 (74%): a flow signal extending through the retinal pigment epithelium. No definitive retinal-choroidal anastomosis was observed; however, projection artifacts confounded the interpretation of deeper structures. An increase in the intensity of the high-flow tuft was seen during the progression or recurrence of Type 3 NV. Intravitreal anti-vascular endothelial growth factor therapy caused a reduction in the intensity of the high-flow tuft which was not sustained.

CONCLUSION

Compared with conventional imaging, OCTA may improve detection and delineation of vascular changes occurring in Type 3 NV. Cross-sectional and en face OCTA may prove useful in studying the pathogenesis and guiding the management of these lesions.

AN UPDATED STAGING SYSTEM OF TYPE 3 NEOVASCULARIZATION USING SPECTRAL DOMAIN OPTICAL COHERENCE TOMOGRAPHY

PURPOSE

To comprehensively investigate spectral domain optical coherence tomography features associated with Type 3 neovascularization and determine the prevalence of each feature and to develop an updated staging system for Type 3 neovascularization based on spectral domain optical coherence tomography findings.

METHODS

The authors retrospectively analyzed 34 eyes with new-onset Type 3 neovascularization. Spectral domain optical coherence tomography images at onset of Type 3 neovascularization, immediately after the first injection, and at the final quiescent visit were analyzed for the presence of specific optical coherence tomography features. In addition, when available, optical coherence tomography images from the visit before onset were studied.

RESULTS

Among 18 eyes with preonset optical coherence tomography, 77.8% had preexisting intraretinal hyperreflective foci (precursor lesion). In the same group of eyes, 44.4% and 27.8% exhibited outer plexiform layer disruption and outer plexiform layer downward deflection, respectively. At the onset of detectable Type 3 neovascularization, all 34 eyes demonstrated a hyperreflective focus with cystoid macular edema and 85.3% exhibited disruption of the retinal pigment epithelium. Serous pigment epithelial detachment and subretinal fluid were present in 67.6% and 23.5% of eyes at onset, respectively. The rate of cystoid macular edema decreased from 100% to 17.6% after a single injection. At the final quiescent visit, focal atrophy at the site of Type 3 lesions, as evidenced by outer retinal and retinal pigment epithelium disruption developed in 88.2% and 52.9% of eyes, respectively.

CONCLUSION

An updated staging system of Type 3 lesions was developed based on spectral domain optical coherence tomography findings. A precursor stage consists of a punctate hyperreflective focus in the outer retina. The subtle detection of associated outer plexiform layer disruption and downward deflection may indicate that this precursor lesion is more likely to progress to an active Type 3 neovascular lesion. Stage 1 consists of a larger intraretinal hyperreflective lesion associated with cystoid macular edema but without outer retinal disruption. Stage 2 is notable for outer retinal disruption that occurs with retinal pigment epithelium disruption in most of the cases. Stage 3 is defined by an intraretinal hyperreflective lesion that extends through the retinal pigment epithelium to vascularize a drusenoid pigment epithelial detachment creating a serous component of the pigment epithelial detachment.

DIAGNOSIS OF TYPE 3 NEOVASCULARIZATION BASED ON OPTICAL COHERENCE TOMOGRAPHY IMAGES

PURPOSE

To evaluate the concordance of an optical coherence tomography (OCT)-based diagnosis of Type 3 neovascularization and an indocyanine green angiography (ICGA)-based diagnosis in neovascular age-related macular degeneration (AMD).

METHODS

This observational case series includes 263 eyes from 263 patients who were diagnosed with treatment-naive neovascular AMD. Patients exhibiting at least three of the following OCT features were diagnosed with Type 3 neovascularization: subfoveal choroidal thickness <200 μm, presence of intraretinal fluid accumulation, absence of subretinal fluid, gently-sloping dome-shaped retinal pigment epithelial detachment or trapezoid-shaped retinal pigment epithelial detachment without an obvious peak, and intraretinal mass lesion. The incidence of cases exhibiting three or more OCT features was compared among different subtypes of neovascular AMD. Additionally, the concordance of OCT-based diagnosis and ICGA-based diagnosis was evaluated.

RESULTS

Three or more OCT features were noted in 8 of 82 (9.8%) eyes with typical neovascular AMD, 4 of 147 (2.7%) eyes with polypoidal choroidal vasculopathy, and 30 of 34 (88.2%) eyes with Type 3 neovascularization, respectively. The incidence was significantly greater in Type 3 neovascularization than in the other subtypes of neovascular AMD (P < 0.001). Of patients diagnosed with Type 3 neovascularization using ICGA-based methods, 88.2% were also diagnosed with Type 3 neovascularization using OCT-based methods. Only 5.2% of patients diagnosed with other subtypes of neovascular AMD using ICGA-based methods were diagnosed with Type 3 neovascularization using OCT-based methods.

CONCLUSION

Optical coherence tomography-based diagnosis of Type 3 neovascularization showed relatively high concordance compared with ICGA-based diagnosis. This method may be useful in clinical practice.

Type 3 neovascularization: evolution, association with pigment epithelial detachment, and treatment response as revealed by spectral domain optical coherence tomography

PURPOSE

To demonstrate the evolution and treatment response of Type 3 neovascularization using spectral domain optical coherence tomography.

METHODS

We retrospectively analyzed 40 eyes treated with intravitreal anti-vascular endothelial growth factor therapy for Type 3 neovascularization over a variable follow-up period.

RESULTS

In 17 eyes, spectral domain optical coherence tomography captured the development of Type 3 neovascularization from punctate hyperreflective foci that preceded any outer retinal defect. The more mature Type 3 lesions were associated with outer retinal disruption and adjacent cystoid macular edema. In addition, 37 of 40 Type 3 lesions (93%) were associated with an underlying pigment epithelial detachment, of which 26 (70%) were drusenoid, 6 (16%) serous, and 5 (14%) mixed. Type 3 vessels appeared to leak fluid into the pigment epithelial detachment cavity, creating serous pigment epithelial detachments as large as 925 μm in maximal height. Treatment with anti-vascular endothelial growth factor agents led to prompt involution of the lesion and resorption of the intraretinal and subretinal pigment epithelium fluid after one or two injections (median = 1).

CONCLUSION

In some eyes with age-related macular degeneration, the earliest sign of Type 3 neovascularization is punctate hyperreflective foci above the external limiting membrane. The mature Type 3 lesions and associated serous pigment epithelial detachments are highly responsive to anti-vascular endothelial growth factor therapy.

Geographic atrophy in patients receiving anti-vascular endothelial growth factor for neovascular age-related macular degeneration

PURPOSE

To examine factors associated with the apparent growth of geographic atrophy (GA) in a consecutive series of eyes with treatment-naive neovascular age-related macular degeneration receiving intravitreal anti-vascular endothelial growth factor therapy on a treat-and-extend regimen.

METHODS

This was a retrospective cohort study. Two independent graders identified areas of GA using near-infrared reflectance imaging and spectral domain optical coherence tomography (SD-OCT). Neovascular lesion subtypes were classified based on fluorescein angiography (FA) as occult choroidal neovascularization, classic choroidal neovascularization, retinal angiomatous proliferation, or mixed choroidal neovascularization, and by the anatomical classification system which utilizes FA and SD-OCT as Types 1 (sub-retinal pigment epithelium), 2 (subretinal), 3 (intraretinal), or mixed neovascularization.

RESULTS

Ninety-one patients (94 eyes) fit the inclusion criteria, of which 52 eyes (55.3%) experienced apparent GA growth. The odds of developing apparent GA were significantly lower in Type 1 neovascularization compared to the other lesion types (P < 0.001). Using both FA and SD-OCT to classify neovascular age-related macular degeneration significantly improves the goodness of fit in the correlation between apparent GA growth and baseline neovascular lesion type (P < 0.001).

CONCLUSION

Treatment-naive neovascular age-related macular degeneration eyes with Type 1 neovascularization at baseline were less likely to develop GA than eyes with other types. The correlation between apparent GA growth and subtype of neovascularization is stronger when lesions are classified with an anatomic grading that utilizes both FA and SD-OCT.

The incidence of neovascular subtypes in newly diagnosed neovascular age-related macular degeneration

PURPOSE

To determine the frequency of neovascularization subtypes as determined by fluorescein angiography (FA) alone vs FA and optical coherence tomography (OCT) grading in age-related macular degeneration (AMD).

DESIGN

Retrospective cohort.

METHODS

participants: Newly diagnosed neovascular AMD patients who initiated intravitreal anti-vascular endothelial growth factor therapy by 1 physician from October 1, 2005 to December 1, 2012. interventions: Two independent graders classified the baseline lesions using FA alone and FA+OCT. main outcome measures: Analysis of the frequency of lesion subtypes by FA alone or FA+OCT and agreement between both classification systems was performed.

RESULTS

A total of 232 patients (266 eyes) fit the inclusion criteria. Mean age was 86.3 years; 67.7% of eyes (180/266) were from female patients, and 95.5% (254/266) were from white patients. The distribution using FA alone was 49.6% (132/266), 12.0% (32/266), 28.6% (76/266), and 9.8% (26/266) among occult, classic, retinal angiomatous proliferation, and mixed choroidal neovascularization, respectively. With FA+OCT, 39.9% (106/266), 9.0% (24/266), 34.2% (91/266), and 16.9% (45/266) were type 1 (sub-retinal pigment epithelium), type 2 (subretinal), type 3 (intraretinal), and mixed neovascularization (NV), respectively. The κ statistic was 0.65 (standard error ±0.37, P < .001) between the 2 classification systems, representing good agreement.

CONCLUSION

With both FA-alone and FA+OCT grading, we found a higher incidence of type 3 NV in eyes with newly diagnosed neovascular AMD than that reported in prior studies. The κ statistic between the 2 classification systems showed "good" agreement. The discrepancies are likely attributable to the identification of a higher frequency of type 3 and mixed NV and a lower frequency of type 1 NV with the aid of OCT.

Type 1 idiopathic macular telangiectasia associated with type 3 neovascularization

PURPOSE

To report the case of a patient with unilateral idiopathic macular telangiectasia (IMT) associated with type 3 neovascularization.

METHODS

Observational case report.

RESULTS

We describe a case of an 85-year-old woman who presented at our department with a gradual vision loss in her left eye (LE). Her best-corrected visual acuity (BCVA) was 20/200 in the LE. Fundus examination showed 2 small hemorrhages located nasally to the LE fovea, as well as lipid exudates. Fluorescein angiography revealed early hyperfluorescence corresponding to the dilated capillaries. Spectral-domain optical coherence tomography (SD-OCT) showed several microaneurysms within the inner retinal layers. Late indocyanine green angiography revealed a focal hyperfluorescence corresponding to a type 3 neovascularization. No signs of IMT or type 3 neovascularization were detected in the right eye. Based on these findings, the patient was diagnosed with type 1 IMT and coincident type 3 neovascularization. The LE was treated with intravitreal anti-vascular endothelial growth factor (anti-VEGF) injections. Twenty-four months later, SD-OCT revealed regression of the exudative signs, and LE BCVA improved to 20/100.

CONCLUSION

We describe the case of an unusual association between older-onset IMT and type 3 neovascularization, and subsequent regression by anti-VEGF injections. We propose a new IMT subtype called type 1C for this association. Further research must be done in order to establish the pathophysiologic mechanism and likelihood of this association.