POOR LONG-TERM OUTCOME OF ANTI-VASCULAR ENDOTHELIAL GROWTH FACTOR THERAPY IN NONPROLIFERATIVE MACULAR TELANGIECTASIA TYPE 2

Retinal pigment epithelial cells reduce vascular leak and proliferation in retinal neovessels

In multiple neurodegenerative diseases, including age-related macular degeneration, retinitis pigmentosa, and macular telangiectasia type 2 (MacTel), retinal pigment epithelial (RPE)-cells proliferate and migrate into the neuroretina, forming intraretinal pigment plaques. Though these pigmentary changes are hallmarks of disease progression, it is unknown if their presence is protective or detrimental.Here, we first evaluated the impact of pigment plaques on vascular changes and disease progression in MacTel. In a retrospective, longitudinal study, we analyzed multimodal retinal images of patients with MacTel and showed that pigment plaques were associated with decreased vascular leakage and stabilized neovascular growth. We then modeled the underlying pathomechanisms of pigment plaque formation in aberrant neovascular growth using the very-low-density lipoprotein receptor mutant (Vldlr-/-) mouse. Our data indicated that during RPE-proliferation, migration and accumulation along neovessels RPE-cells underwent epithelial-mesenchymal transition (EMT). Pharmacologic inhibition of EMT in Vldlr-/- mice decreased pigment coverage, and exacerbated neovascular growth and vascular leakage.Our findings indicate that the proliferation, migration and perivascular accumulation of RPE-cells stabilize vascular proliferation and exudation, thereby exerting a protective effect on the diseased retina. We conclude that interfering with this "natural repair mechanism" may have detrimental effects on the course of the disease and should thus be avoided.

Sight threatening diabetic retinopathy in patients with macular telangiectasia type 2

PURPOSE

Although diabetes is highly prevalent in patients with MacTel, progression to severe non-proliferative (NPDR) and proliferative diabetic retinopathy (PDR) is rarely reported. We report multimodal imaging features of sight-threatening diabetic retinopathy (STDR) in eyes with macular telangiectasia type 2 (MacTel).

METHODS

Retrospective case series of seven participants of the MacTel Study at the Moorfields Eye Hospital NHS Foundation Trust study site and one patient from the Institute of Retina and Vitreous of Londrina, Brazil. Sight threatening diabetic retinopathy was defined as severe NPDR, PDR or diabetic macular edema.

RESULTS

We report imaging features of 16 eyes of eight patients (7/8, 87.5% female) with diagnoses of MacTel and type 2 diabetes mellitus with STDR. Mean (SD) age was 56 (8.3) years. Patients were followed-up for a mean time of 9.1 (4.7) years. A total of 10/16 (62.5%) eyes showed PDR and 2/16 (12.5%) eyes presented a macular epiretinal neovascularization.

CONCLUSIONS

People with diabetes mellitus and MacTel may not be protected from STDR as previously reported. Although the two diseases rarely co-exist, regular monitoring for diabetic retinopathy progression is recommended according to baseline retinopathy severity grades in line with established international guidelines. The presence of MacTel may not modify extended screening intervals, but there is no current evidence. The limited case series in the literature support treatment for complications and should follow the standard of care for either condition. Due to dual pathology, reactivation may be difficult to diagnose on standard imaging and multimodal imaging is recommended.

Macular Telangiectasia Type 2: A Comprehensive Review

Macular telangiectasia Type 2 (MacTel) is a gradually progressive disease that affects the quality of life by impairing both distant and near vision. It had previously been considered a vascular condition, but recent evidence suggests a neurodegenerative etiology, with primary involvement of Muller cells. Retinal pigment epithelium (RPE) hyperplasia and subretinal neovascularization (SNV) are responsible for most of the vision loss in advanced cases. Neurotrophic factors in the non-proliferative phase and intravitreal anti-Vascular Endothelial growth factor (VEGF) in the proliferative phase have shown to retard the progression of the disease. This review will discuss the pathophysiology, clinical features, important diagnostic imaging studies and available treatment options for MacTel.

Clinical Features of Untreated Type 2 Macular Telangiectasia and Efficacy of Anti-Vascular Endothelial Growth Factor Therapy in Macular Neovascularization

Objectives:

To compare best corrected visual acuity (BCVA), central macular thickness (CMT), and central choroidal thickness (CCT) in patients with type 2 macular telangiectasia (MacTel 2) and a control group and to evaluate the efficacy of intravitreal anti-vascular endothelial growth factor (anti-VEGF) treatment in MacTel 2 patients with macular neovascularization (MNV).

Materials and Methods:

We conducted a retrospective chart review of consecutive MacTel 2 patients who underwent a full ophthalmologic examination including BCVA and dilated fundus examination with slit-lamp biomicroscopy, fluorescein angiography, and optical coherence tomography imaging at baseline and follow-up visits. BCVA, CMT, and CCT were compared between all identified patients (n=26) and a control group (n=30). A subgroup analysis was performed among eyes with MNV (n=7) before and after treatment.

Results:

CMT and CCT were significantly lower in the MacTel 2 group compared to the control group. Forty-one treatment-naive eyes without MNV proliferation showed no significant change in BCVA, CMT, or CCT during follow-up. Eight eyes of 7 MacTel 2 patients developed MNV during follow-up. All of the patients were treated with intravitreal anti-VEGF.

Conclusion:

It is important to closely follow MacTel 2 patients for MNV development. To avoid adverse effects, we prefer to monitor patients who have not yet developed MNV. Patients with proliferative MacTel 2 with decreasing visual function may benefit from intravitreal anti-VEGF treatment.

Imaging endpoints for clinical trials in MacTel type 2

INTRODUCTION

Macular Telangiectasia type 2 (MacTel) is a bilateral neurodegenerative disease associated with dysfunction in the serine and lipid metabolism resulting in loss of Muller cells and photoreceptors. Typical structural changes include vascular abnormalities, loss of retinal transparency, redistribution of macular pigment and thinning of the central retina with photoreceptor loss. The presence and extent of photoreceptor loss, as visible on Optical Coherence Tomography (OCT) ("disease severity scale"), correlate with functional loss and the limitation of photoreceptor loss appears to be the most promising therapeutic approach. Ongoing clinical trials of ciliary neurotrophic factor (CNTF) implants for the treatment of MacTel are using this outcome to evaluate efficacy. An ideal outcome measure provides the ability to quantify the extent of the disease progression with precision and reproducibility.

METHODS

This review describes the changes and findings on different imaging techniques including fluorescein- and OCT angiography, blue light reflectance, 1- and 2-wavelength autofluorescence and OCT.

RESULTS

The possibilities of objective quantification of the severity of MacTel and correlation with functional characteristics such as best-corrected visual acuity (BCVA) and microperimetry and their applications as quantitative imaging endpoints for clinical treatment trials are discussed. OCT and especially en face OCT could be demonstrated as precise and reproducible methods to quantify the area of photoreceptor loss, which correlated highly significantly with functional loss in microperimetry.

CONCLUSION

The analysis of the area of photoreceptor loss on en face OCT is the most reliable imaging endpoint for treatment trials in MacTel. This method is already being used in ongoing randomized trials.

Choroidal vascularity index: an enhanced depth optical coherence tomography-based parameter to determine vascular status in patients with proliferative and non-proliferative macular telangiectasia

KEY MESSAGES

The pathogenesis of subretinal neovascularization (SRNV) due to macular telengiectasia (MacTel 2) has not fully elucidated. This optical coherence tomography (OCT)-based method can provide better understanding of the pathogenesis of SRNV due to MacTel 2.

PURPOSE

To evaluate the choroidal vascular index (CVI) through optical coherence tomography (OCT) on eyes with proliferative macular telangiectasia type 2 (MacTel 2) or non-proliferative MacTel 2, and in healthy individuals.

METHODS

Macular enhanced depth imaging OCT scans on 42 eyes of 21 patients with non-proliferative MacTel 2, on 32 eyes of 20 patients with proliferative MacTel 2, and on 38 eyes of 32 control patients were analyzed by adjusting for age-gender-axial length. Proliferative MacTel 2 was diagnosed when subretinal neovascularization (SRNV) was simultaneously observed in the non-proliferative phase. Binarization methods of ImageJ software were used to analyze images, and total choroid area (TCA), luminal area (LA) and stromal area (SA) were obtained. CVI was characterized as the ratio of LA to TCA.

RESULTS

The mean TCA and SA were significantly higher in group 1 and group 2 when compared with group 3 (3.36 ± 0.29 mm² vs. 3.27 ± 0.76 mm² vs. 2.49 ± 0.24 mm², p < 0.001; 1.15 ± 0.31 mm² vs. 1.10 ± 0.69 mm² vs. 0.35 ± 0.23 mm², respectively; p < 0.001). Although LA was relatively higher in group 1 and group 2 than group 3, no statistically significant difference was observed (2.22 ± 0.14 mm² vs. 2.17 ± 0.15 mm² vs. 2.13 ± 0.21 mm²) (p = 0.088). CVI was significantly lower in group 1 than other groups (0.65 ± 0.01 vs 0.67 ± 0.02 vs 0.68 ± 0.02) (p < 0.001).

CONCLUSION

As an OCT screening method, CVI may be used to assess the vascular status of the choroid on the eyes which are naive for or were exposed to SRNV secondary to MacTel 2, and to elucidate the pathogenesis of this disease.

Longitudinal Assessment of Remnant Foveal Cone Structure in a Case Series of Early Macular Telangiectasia Type 2

Purpose

To determine the extent of remnant cone structure within early foveal ellipsoid zone (EZ) lesions in macular telangiectasia type 2 longitudinally using both confocal and split detector adaptive optics scanning light ophthalmoscopy (AOSLO).

Methods

Spectral domain optical coherence tomography (SDOCT), confocal and split detector AOSLO were acquired from seven patients (10 eyes) with small (early) EZ lesions on SDOCT secondary to macular telangiectasia type 2 at baseline, 6 months, and 12 months. The presence of cone structure on AOSLO in areas of EZ loss as well as cones at 1° eccentricity, and their change over time were quantified.

Results

By split detector AOSLO, remnant cone structure was identified within and on the borders of all foveal EZ lesions. Within the extent of these lesions, cone spacing ranged from 4.97 to 9.95 µm at baseline, 5.30 to 6.10 µm at 6 months, and 4.99 to 7.12 µm at 12 months. Four eyes with significantly smaller EZ lesions showed evidence of recovery of EZ reflectivity on SDOCT B-scans. Remnant cone structure was identified in some areas where EZ reflectivity recovered at the following time point. Eyes that showed recovery of EZ reflectivity had a continuous external limiting membrane.

Conclusions

Remnant cone structure can persist within small SDOCT-defined EZ lesions, which can wax and wane in appearance over time. AOSLO can help to inform the interpretation of SDOCT imaging.

Translational Relevance

The absence of EZ in early macular telangiectasia type 2 and other retinal conditions needs careful interpretation because it does not always indicate an absence of underlying cone structure. The integrity of the external limiting membrane may better predict the presence of remnant cone structure and recovery of EZ reflectivity.

Optical coherence tomography-angiography for monitoring neovascularisations in macular telangiectasia type 2

PURPOSE

To evaluate the utility of optical coherence tomography-angiography (OCT-A) for monitoring activity, progression and response to therapy of neovascularisations (NVs) secondary to macular telangiectasia type 2 (MacTel).

METHODS

In a retrospective analysis, eyes with NVs secondary to MacTel were reviewed over a period of ≥8 months. Examinations at monthly intervals included visual acuity testing, dilated funduscopy, spectral domain-OCT and OCT-A. Eyes were treated with intravitreal VEGF (vascular endothelial growth factor)-inhibitors following a pro-re-nata (PRN) regime, and treatment decisions were based on morphological signs of activity as determined by B-scan OCT and funduscopy. Signs of neovascular activity were defined as an increase in retinal thickness, presence/increase of intraretinal/subretinal fluid and haemorrhages.

RESULTS

A total of 19 eyes from 17 patients were analysed. Patients were evaluated over a mean period of 13.4 months (range: 8.9 to 24.2). OCT-A permitted the monitoring of both treatment effects (regression) and progression (growth) of NVs, but not neovascular activity. The growth of neovascular vessels was detectable in OCT-A before signs of activity occurred on OCT. NVs showed a progressive growth over time despite PRN-treatment and preferentially grew and extended within areas characterised by a focal reduction of choriocapillaris perfusion.

CONCLUSIONS

The results indicate that OCT-A represents a useful imaging modality for monitoring NV-progression and treatment effects in MacTel. We demonstrate its advantages over conventional B-scan OCT imaging, including an earlier detection of NV-progression, and propose an adjustment of the current OCT-controlled PRN treatment regime in order to prevent NV-progression and subsequent functional loss in neovascular MacTel.

Evaluation of Choroidal Thickness in Patients with Proliferative and Non-Proliferative Macular Telangiectasia Using Enhanced Depth Imaging Optical Coherence Tomography

Purpose: To compare subfoveal choroidal thickness (SFCT) in eyes with non-proliferative macular telangiectasia (MacTel) type 2 with or without subretinal neovascularization (SRNV) and healthy control eyes.Methods: Consecutive patients with non-proliferative and proliferative MacTel type 2 were included in the current study. For comparisons subjects with no ocular pathology were recruited and used as controls. Best corrected visual acuity (BCVA), central macular thickness (CMT), and subfoveal choroidal thickness (SFCT) were evaluated. Since axial length (AL) may affect choroidal thickness, AL measurements were performed to avoid confusion in SFCT between the groups.Results: Of the 63 eyes of 38 MacTel type 2 patients, 38 eyes had only MacTel type 2 (group 1) and 25 eyes had SRNV caused by MacTel type 2 (group 2). Fourty eyes of 20 subjects served as controls (group 3). BCVA was found to be significantly higher in control group compared with group 1 and group 2 (p < .005). Whereas, no difference was detected between group 1 and group 2 (p = .75). No difference was noted in CMT between the groups (p = .35). Axial length measurement was very similar among all three groups (p = .62). After adjusting for age and axial length SFCT was significantly thinner in group 3 than the other groups (p < .001), but no statistically significant difference was found between group 1 and group 2.Conclusions: Choroidal thickness did not vary between eyes with MacTel type 2 with SRNV and without SRNV. Choroid was significantly thicker in MacTel type 2 with SRNV and without SRNV than healthy eyes.

Progression characteristics of ellipsoid zone loss in macular telangiectasia type 2

PURPOSE

To investigate the progression characteristics of ellipsoid zone (EZ) loss in eyes with macular telangiectasia type 2 (MacTel) as reflected by area and linear measurements, and their relevance for visual acuity.

METHODS

Participants were selected from the MacTel Study cohort. Linear and area measurements of EZ loss were performed in Spectral-Domain Optical Coherence Tomograph (SD-OCT) volume scans. Progression characteristics and correlations between linear and area measurements were analysed using linear mixed effects models.

RESULTS

A total of 134 eyes of 70 patients were included (85 eyes with follow-up, mean 4.7 years, range: 1.4-8 years). Ellipsoid zone (EZ) loss significantly progressed at a mean annual increment of 0.057 mm² (p = 0.005). The progression rate was non-linear and interacted significantly with initial EZ lesion size indicating an exponential growth before reaching a plateau. There was a strong heterogeneity in area sizes between fellow eyes. EZ break length had a significant linear effect on EZ break area (b = 1.06, p < 0.001) and could predict it. The location of the EZ break had a significant impact on visual acuity.

CONCLUSION

Ellipsoid zone (EZ) loss in MacTel has a non-linear progression characteristic, and its rate depends on area size at baseline, which must be taken into account at sample selection in clinical trials. Our results show a good correlation of linear and area measures of EZ loss and a segregation of best-corrected visual acuity by EZ location, which may help routine clinical practice.

Evaluation of 1-year follow-up results of macular telangiectasia type 2 cases by optical coherence tomography angiography

The results of 1-year follow-up with optical coherence tomography angiography (OCTA) of 3 patients with macular telangiectasia type 2 (MacTel 2) were evaluated. The 3X3 mm OCTA imaging was performed in January 2017 and February 2018. The superficial and deep capillary plexus vascular density changes of the whole area, the parafoveal temporal and parafoveal nasal areas were examined. The mean whole, parafoveal temporal, and parafoveal nasal vessel densities at superficial capillary plexus were 51.31, 50.39, 54.57 at baseline and 49.93, 46.79, 51.83 at 1-year follow-up, respectively. The mean whole, parafoveal temporal and parafoveal nasal vessel densities at deep capillary plexus were 59.06, 59.05, 63.39 at baseline and 52.18, 54.68, 57.9 at 1-year follow-up, respectively. In this case series, it was shown quantitatively that vessel densities of MacTel2 patients markedly decreased over time, more pronounced in the deep capillary plexus.

Progression of vascular changes in macular telangiectasia type 2: comparison between SD-OCT and OCT angiography

PURPOSE

To investigate the different appearances of vascular changes in macular telangiectasia type 2 (MacTel) and to describe their possible progression, the vascular patterns in different retinal layers were analyzed with optical coherence tomography angiography (OCT-A) and the findings were correlated with a spectral-domain OCT (SD-OCT) disease severity scale based on the extent of ellipsoid zone (EZ) loss.

METHODS

Participants from the MacTel Study Group in Muenster and a healthy cohort were investigated with OCT-A using RTVue XR Avanti. After segmentation of the superficial capillary network, the deep capillary network, and the outer retina (OR), flow density was analyzed using Optovue software. Then, the images were exported using the software Fiji (National Institute of Mental Health, Bethesda, MD, USA) and analyzed with the automated MATLAB program (Mathworks, Version R2014b). Four parameters (total vessel length, number of vessel branches, number of vessel segments, and fractal dimension) were examined on the vascular skeletons (temporal, foveal, nasal, and total fields of the ETDRS grid). In addition, linear and area measurements of EZ loss were performed on SD-OCT volume scans. Progression characteristics and correlation between linear and area measurements were analyzed using linear mixed effects models.

RESULTS

Twenty eyes of healthy probands (20 OCT-A and 20 SD-OCT scans) and 122 eyes of 61 MacTel patients were included. In order to classify the severity of the disease, MacTel eyes were assigned to a SD-OCT "disease severity scale" (grade 1 = no EZ loss; grade 2 = EZ loss temporal to the fovea; grade 3 = EZ loss including the fovea and the region nasal to the fovea). Flow density and total vessel length showed only limited differences between healthy eyes and different grades of MacTel, but particularly the numbers of branches and vessel segments, as well as the fractal dimension values, demonstrated significant and progressive reduction in the superficial and deep capillary networks of the temporal, nasal, and total ETDRS fields. Moreover, the outer retina showed a progressive presence of hyperreflective material in SD-OCT grades 2 and 3 eyes with associated vascular patterns in the OR on OCT-A.

CONCLUSIONS

In SD-OCT, the severity of MacTel is characterized by progressive EZ loss, which may be used as a simple clinical "disease severity scale". In addition, OCT-A enables visualization and quantification of vascular patterns with mathematical methods. The morphological progression of the disease correlated significantly with progressive vascular changes, especially in respect of the numbers of branches and vessel segments as well as fractal dimension. This suggests that the severity of neurodegenerative and neurovascular changes develops in parallel and that the analysis and quantification of the vascular changes in the superficial and deep capillary networks may become an additional parameter for future treatment trials. Moreover, the significant association between hyperreflective material progressively visible on SD-OCT in the OR, which most often contains vessels in OCT-A, and advancing SD-OCT severity grades, as well as vascular changes in OCT-A, supports the concept of retinal neovascularization in the OR in patients with advanced MacTel.

Management of Idiopathic Macular Telangiectasia Type 2

Macular telangiectasia type 2 (MacTel) is a relatively rare disease without established treatments. Although MacTel was previously considered a primarily vascular condition, the thinking on its pathogenesis has shifted to it now being considered principally a neurodegenerative disease. This has resulted in a subsequent change in the approach to treatment toward neuro-protection for the non-proliferative phase of this disease. Carotenoid supplementation has had mixed results. Ciliary neurotrophic factor (CNTF) has demonstrated some promising early results, but further study is necessary to determine its actual effect. Some structural improvements have been seen in the non-proliferative phase with oral acetazolamide but without accompanying functional improvement. Anti-vascular endothelial drugs have been studied and not found to have benefit in the non-proliferative phase of disease but have demonstrated significant structural and functional value in the treatment of secondary neovascularization. There is no level I evidence for the various proposed MacTel treatments, and efforts need to be directed toward conducting multicenter randomized trials to better understand possible treatments for this condition.

LONGITUDINAL CORRELATION OF ELLIPSOID ZONE LOSS AND FUNCTIONAL LOSS IN MACULAR TELANGIECTASIA TYPE 2

PURPOSE

To compare ellipsoid zone (EZ) loss and functional loss in macular telangiectasia (MacTel) type 2 longitudinally.

METHODS

Prospective natural history study. Ellipsoid zone loss was measured in en-face images created from spectral domain optical coherence tomography. Functional loss was assessed by best-corrected visual acuity and microperimetry, counting the number of test points with impaired function.

RESULTS

A total of 56 eyes of 31 participants were followed for 4.5 ± 1.2 years. Ellipsoid zone loss was 18,600 ± 3,917.3 pixel at baseline (≈0.59 mm) and increased 2,627.8 ± 427.9 pixel (≈0.08 mm) per year. Best-corrected visual acuity decreased 2.2 ± 0.9 letters per year. Change in EZ loss correlated significantly with change in relative and absolute scotomas (r = 0.62; P-value < 0.0001 and r = 0.72; P-value < 0.0001), but not with loss of best-corrected visual acuity. Functional loss showed a similar frequency of progression as EZ loss, but a higher rate of "regression," likely due to higher variability of the measurement, assuming a progressive neurodegenerative disease.

CONCLUSION

The results of the authors support EZ loss as surrogate measure for visual function in MacTel type 2. Being objective, EZ loss might be considered more suitable than microperimetry as primary end point in future interventional trials.

CORRELATION OF CLINICAL AND STRUCTURAL PROGRESSION WITH VISUAL ACUITY LOSS IN MACULAR TELANGIECTASIA TYPE 2: MacTel Project Report No. 6-The MacTel Research Group

PURPOSE

To evaluate progression of macular telangiectasia Type 2 lesions and their correlation with visual acuity.

METHODS

An international multicenter prospective study with annual examinations including best-corrected visual acuity (BCVA), fundus photography, fluorescein angiography, and optical coherence tomography images graded centrally. Mixed models were used to estimate progression rates, and a generalized linear model to compute the relative risk of BCVA loss, loss of ellipsoid zone (EZ) reflectivity, development of pigment plaques, or neovascularization.

RESULTS

One thousand and fourteen eyes of 507 participants were followed for 4.2 ± 1.6 years. Best-corrected visual acuity decreased 1.07 ± 0.05 letters (mean ± SE) per year. Of all eyes, 15% lost ≥15 letters after 5 years. Of the eyes without EZ loss, 76% developed a noncentral loss. Of the eyes with noncentral loss, 45% progressed to central EZ loss. The rate of BCVA loss in eyes with noncentral EZ loss at baseline was similar to eyes without EZ loss. The rate of BCVA loss was significantly higher in eyes with central EZ loss at baseline (-1.40 ± 0.14 letters, P < 0.001).

CONCLUSION

Ellipsoid zone loss is frequently found in macular telangiectasia Type 2 and is an important structural component reflecting visual function. Its presence in the fovea significantly correlates with worse visual prognosis.

EFFICACY OF INTRAVITREAL AFLIBERCEPT IN MACULAR TELANGIECTASIA TYPE 1 IS LINKED TO THE OCULAR ANGIOGENIC PROFILE

PURPOSE

To evaluate intravitreal aflibercept in macular telangiectasia Type 1 (MacTel 1) patients and measure their ocular angiogenic profile.

METHODS

Eight subjects with MacTel 1 refractory to bevacizumab, ranibizumab, or laser therapy and switched to aflibercept were included. Best-corrected visual acuity, central macular thickness, and cystic areas quantified on optical coherence tomography B-scans were assessed during 12 months. Perifoveal capillary densities were measured on optical coherence tomography angiography. Aqueous humor was sampled from six patients and eight control subjects undergoing cataract extraction. Growth factors were quantified using a multiarray immunoassay.

RESULTS

Over 12 months, patients received 6.6 ± 1.4 (range, 5-8) intravitreal aflibercept injections. Twelve months after switching to aflibercept, best-corrected visual acuity increased by ≥5 letters in 5 of 8 patients, compared with preaflibercept levels. Mean best-corrected visual acuity improved from 79.6 (∼20/50) to 88.0 (∼20/35) Early Treatment Diabetic Retinopathy Study letters (P = 0.042), and central macular thickness decreased from 434 ± 98 μm to 293 ± 59 μm (P = 0.014). Compared with control subjects, the profile of angiogenic factors in MacTel 1 eyes revealed no difference in vascular endothelial growth factor-A levels but significantly higher levels of placental growth factor (P = 0.029), soluble vascular endothelial growth factor receptor-1 (sFlt-1; P = 0.013), vascular endothelial growth factor-D (P = 0.050), and Tie-2 (P = 0.019). Placental growth factor levels inversely correlated with both superficial and deep capillary plexus densities on optical coherence tomography angiography (P = 0.03).

CONCLUSION

The clinical response to aflibercept coupled to the angiogenic profile of MacTel 1 eyes support the implication of the placental growth factor/Flt-1 pathway in MacTel 1.

Intravitreal anti-VEGF treatment for subretinal neovascularisation secondary to type 2 idiopathic juxtafoveolar telangiectasia

PURPOSE

To assess the long-term outcome of patients with subretinal neovascular membrane (SRNVM) secondary to type 2 idiopathic juxtafoveolar telangiectasia (IJT) receiving intravitreal anti-VEGF (vascular endothelial growth factor) injections.

METHODS

A total of 14 eyes of 12 patients treated with intravitreal anti-VEGF for SRNVM related to type 2 IJT were retrospectively assessed.

RESULTS

Nine men and 3 women with a mean age of 66 years (SD 12, range 47-87 years) were diagnosed with IJT-related SRNVM. On average, 6.8 injections (SD 5.5, range 3-18) were given per eye. Ten eyes were treated with ranibizumab, 3 eyes with bevacizumab and 1 eye received both substances. The median follow-up after the last injection was 31 months (IQR: 18, 48). In 6 eyes, BCVA improved by 1-4 lines (mean Δ +2.0 lines), 1 eye remained stable and 7 eyes showed decline of vision by 1-5 lines (mean Δ -2.1 lines). The baseline central foveal thickness was significantly reduced from a mean of 323 (SD 87) to 266 µm (SD 71 µm) at the last follow-up visit (p = 0.001).

CONCLUSIONS

SRNVM development is a severe complication of type 2 IJT. Since the establishment of intravitreal anti-VEGF treatment laser coagulation and PDT have lost significance. Intravitreal anti-VEGF therapy seems to be safe and effective for the treatment of IJT-related SRNVM. Frequently multiple intravitreal injections are necessary for stabilisation.