CHOROIDAL VASCULAR ALTERATIONS IN AGE-RELATED MACULAR DEGENERATION AND POLYPOIDAL CHOROIDAL VASCULOPATHY

Impact of photodynamic therapy combined with Anti-VEGF vs. Anti-VEGF monotherapy on choriocapillaris vessel density in polypoidal choroidal vasculopathy

PURPOSE

To compare the choriocapillaris vessel density between intravitreal ranibizumab (Lucentis) (IVR) plus photodynamic therapy (PDT) and intravitreal aflibercept (Eylea) (IVA) monotherapy in patients experiencing polypoidal choroidal vasculopathy (PCV).

DESIGN

An observational, retrospective cohort study.

SUBJECTS

Adults with treatment-naïve PCV.

INTERVENTION

IVR plus PDT or IVA monotherapy.

MAIN OUTCOME MEASURES

After propensity-score (PS) matching, study outcomes were compared at 1 month after the final treatment. The primary outcome was a choriocapillaris vessel density, recognized by optical coherence tomography angiography (OCTA). The secondary outcomes included best corrected visual acuity (BCVA), presence of retinal hemorrhage, central macular thickness (CMT) and subfoveal choroidal thickness (SFCT), assessed by optical coherence tomography (OCT).

RESULTS

Initially, 23 patients receiving IVR plus PDT, and 75 patients receiving IVA monotherapy were included. After PS-matching, 19 eyes of 19 patients receiving IVR plus PDT and 38 eyes of 38 patients receiving IVA monotherapy were analyzed. A significantly lower choriocapillaris vessel density in the IVR plus PDT group than the IVA monotherapy group (41.9 % vs. 52.2 %, p = 0.009) was demonstrated. The similarity of the BCVA, occurrence and severity of retinal hemorrhage, CMT, and SFCT between two treatment groups was exhibited.

CONCLUSIONS

The choriocapillaris vessel density was significantly reduced in PCV patients treated with IVR plus PDT compared to those receiving IVA monotherapy.

Pachychoroid disease: review and update

The pachychoroid disease spectrum is a phenotype characterized by alterations in choroidal vasculature which result in outer retinal and choriocapillaris damage and visual loss. The presence of pachyvessels is one of the key features of the pachychoroid phenotype. Recent imaging studies suggest that pachyvessels may form because of choroidal venous congestion in one or more quadrants. The formation of intervortex anastomosis may function as a compensatory mechanism to dissipate the increased venous pressure, while outflow obstruction has been hypothesized to occur at the site of the vortex vein exiting the sclera. This review aims to summarize recent imaging findings and discuss evolution in the understanding of pathogenesis of the pachychoroid disease spectrum. We have summarized notable treatment trials in central serous chorioretinopathy and polypoidal choroidal vasculopathy and included an update of the current diagnostic and management strategies of the entities that are part of the pachychoroid disease spectrum.

HIGHER SUBFOVEAL CHOROIDAL THICKNESS IN CHOROIDAL MELANOMAS THAN IN CHOROIDAL NEVI

PURPOSE

To compare subfoveal choroidal thickness between eyes with choroidal melanoma and choroidal nevi.

METHODS

Retrospective study of 126 consecutive patients in a tertiary ocular oncology center. Eyes with tumors located less than two disk diameters from the fovea were excluded. In eyes with nevi, factors of potential transformation into melanoma were recorded (orange pigment, subretinal fluid, thickness >2 mm, diameter >5 mm, ultrasound hollowness). Subfoveal choroidal thickness was assessed by three independent observers on horizontal spectral-domain optical coherence tomography scans.

RESULTS

Sixty-seven eyes with choroidal melanoma and 59 eyes with choroidal nevi were included. The melanoma and nevi groups did not differ in gender ( P = 0.14) nor age ( P = 0.34). There was a very good agreement between the three independent observers for subfoveal choroidal thickness measurements (intraclass correlation coefficient = 0.89). Mean subfoveal choroidal thickness was higher in melanomas (294.3 ± 89.9 µ m) than nevi (260.3 ± 76.7 µ m) ( P = 0.013), and the difference remained significant between melanomas and 28 nevi with ≥2 growth risk factors (256.3 ± 77.0 µ m) ( P = 0.027). In a multivariate model, the significant contributors to subfoveal choroidal thickness were presence of melanoma ( P = 0.004), younger age ( P < 0.0001), and shorter lesion distance to the fovea ( P = 0.016).

CONCLUSION

Subfoveal choroidal thickness may reflect the interplay between melanocytic tumors and their choroidal microenvironment. Its clinical utility should be explored in future studies.

Quantitative assessment of intervortex anastomosis in central serous chorioretinopathy and fellow eyes: Does the size of anastomotic vessels matter for the diagnosis?

PURPOSE

To evaluate the frequency and size of intervortex anastomosis at the posterior pole on en-face spectral domain optical coherence tomography (SD-OCT) images in central serous chorioretinopathy (CSC) cases and their fellow eyes and its associations with choroidal morphology.

METHODS

Sixty-five treatment-naive eyes of 65 patients with CSC, 65 fellow eyes, and 55 eyes of healthy age-matched participants were included. The presence of intervortex anastomosis at the watershed zone and asymmetry of the choroidal vessels between the superior and inferior macula were evaluated using 6 × 6 mm en-face SD-OCT. The diameter of the widest Haller vessel and the diameter of the widest anastomotic Haller vessel passing through the watershed zone were measured on en-face SD-OCT images. The choroidal vascularity index (CVI) was assessed using ImageJ software.

RESULTS

Intervortex vein anastomosis on the horizontal watershed zone was detected in 75.4% diseased eyes, 61.5% in fellow eyes, and 36.4% in healthy age-matched controls (p < 0.001). The mean CVI was significantly higher in both diseased (74.3 ± 2.3%) and fellow (73.8 ± 2.2%) eyes of CSC cases than in healthy controls (72.5 ± 2.3%) (p = 0.002, p = 0.013, respectively). In the cases with intervortex vein anastomosis, the diameter of the widest anastomotic Haller vessel passing through the watershed zone was 0.40 ± 0.10 mm in diseased eyes, 0.35 ± 0.11 mm in fellow eyes, and 0.30 ± 0.09 mm in healthy age-matched controls (p = 0.001).

CONCLUSIONS

Intervortex anastomosis might be seen as a variation in normal eyes, however, its frequency and the size of anastomotic vessels are significant higher in not only CSC but also in fellow eyes.

Identification of Structures Labeled by Indocyanine Green in the Rat Choroid and Retina Can Guide Interpretation of Indocyanine Green Angiography

Purpose

Indocyanine green (ICG) is an albumin and lipoprotein binding dye absorbing in the far red used in angiography to visualize choroidal vessels (ICG angiography [ICGA]). To guide interpretation, ICG transport in the choroid, RPE, and retina of rats was studied.

Methods

Two conditions were used: RPE/choroid organoculture, incubated for 45 minutes in DMEM medium, 1% fetal bovine serum containing 0.25 mg/mL ICG and RPE/choroid and neural retina flat-mounts at 1 and 6 hours after intravenous ICG injection. Early and late sequences of ICGA were recorded until 6 hours. Ultra-deep red confocal microscope was used to localize ICG in flat-mounts and immunohistochemistry was performed for caveolin-1, tryptase (mast cell marker), and tubulin β3 (a nerve marker).

Results

In the organoculture, ICG penetrated homogeneously in the cytoplasm and stained the membranes of the RPE. At 1 hour after intravenous injection, ICG appeared in fine granules in RPE, partly labeled with caveolin-1 and decreasing at 6 hours. At 1 hour and 6 hours, ICG was found in the retinal vessels, faintly in the inner retina, and in the photoreceptor outer segments at 6 hours. In the choroid, ICG colocalized with mast cells, immunostained with tryptase, and accumulated along the large tubulin β3-labeled nerve bundles. The hypothesis was raised on the interpretation of late ICGA infrared photography in case of transthyretin amyloidosis with neuropathy.

Conclusions

Beside being a vascular dye, ICG is transported from the vessels to the RPE toward the outer retina. It stains mast cells and large choroidal nerves. These observations could help the analysis of ICGA images.

Choroidal Changes After Anti-VEGF Therapy in AMD Eyes With Different Types of Macular Neovascularization Using Swept-Source OCT Angiography

Purpose

Choroidal changes before and after anti-VEGF therapy were investigated in eyes with exudative AMD to determine if there was a difference between eyes with macular neovascularization (MNV) that arises from the choroid (type 1 or 2) versus the retinal circulation (type 3).

Methods

Patients with treatment-naïve AMD were imaged with swept-source optical coherence tomography angiography using a 12 × 12-mm scan pattern. The mean choroidal thickness and choroidal vascularity index (CVI) were measured within 5-mm and 11-mm fovea-centered circles before, at the onset of, and after anti-VEGF therapy.

Results

Forty-one eyes of 37 patients were included; 24 eyes with type 1 MNV, 4 eyes with type 2 MNV, and 13 eyes with type 3 MNV. Within the 5-mm and 11-mm circles, the mean choroidal thickness and CVI measurements increased from pretreatment to the onset of exudation (P ≤ 0.03). The mean choroidal thickness and CVI measurements decreased from the onset of exudation to after treatment (P < 0.001). No significant changes in mean choroidal thickness or CVI were observed when comparing measurements before or after treatment (P ≥ 0.38). No significant differences in mean choroidal thickness or CVI measurements were observed between eyes with type 1 or 2 MNV and type 3 MNV.

Conclusions

In treatment-naïve AMD eyes with MNV, the choroidal thickness and vascularity increased at the onset of exudation and then decreased after anti-VEGF therapy. This finding suggests that these choroidal changes develop in response to the proangiogenic milieu before treatment and in response to treatment, regardless of the site of origin for the MNV.