Purpose: To investigate correlations among macular ganglion cell complex (GCC) layer thickness, macular capillary density, and macular function in patients affected by retinitis pigmentosa (RP). Methods: Fourteen patients (28 eyes) with previous diagnosis of RP were enrolled. The diagnosis of these conditions was made based on both clinical features and electrophysiological examination. All patients underwent a complete ophthalmologic examination, including optical coherence tomography angiography (OCTA) and multifocal electroretinogram (mfERG). Main outcome measures were macular GCC layer thickness; superficial capillary plexus (SCP) vessel density; deep capillary plexus (DCP) vessel density; choriocapillaris plexus (CCP) vessel density; and amplitudes of mfERG N1 and P1 waves. Results: Average GCC thickness was significantly thinner in RP patients (76.0 ± 25.1 and 109.2 ± 17.5 μm, P = 0.028). Superficial capillary plexus density was 42.2 ± 3.4% in the RP group and 51.4 ± 2.3% in the control group (P < 0.001). Deep capillary plexus density was reduced in RP patients (42.7 ± 6.2%) after the comparison with healthy subjects (56.6 ± 2.2%, P < 0.001). Choriocapillaris plexus density was significantly less in RP patients than in the control group (65.3 ± 2.7% and 67.2 ± 1.4%, P = 0.024). Superficial capillary plexus and DCP density were significantly correlated with both mfERG values and GCC thickness. Conclusions: We showed that both choroid and retinal vessels were modified in RP patients after comparison with healthy subjects. Moreover, we demonstrated that the SCP and DCP vessel densities are correlated with the macular function, as well as with the GCC thickness.

The aim of this study was to evaluate retinal and choriocapillaris vessel density using optical coherence tomography angiography (OCTA) in eyes with central retinal vein occlusion (CRVO) and branch retinal vein occlusion (BRVO) complicated by macular edema (ME). Sixty eyes of 60 patients with CRVO or BRVO and ME and 40 healthy subjects underwent measurements of superficial and deep foveal and parafoveal vessel density (FVD, PFVD) and choricapillary density using OCTA at baseline and 60 days after intravitreal dexamethasone implant (IVDEX). FVD and PFVD of the superficial plexus were not significantly lower in CRVO group compared to the controls while in the BRVO group overall PFVD were significantly lower compared to control group (p < 0.001). Overall PFVD of the deep plexus was significantly lower in CRVO and BRVO groups compared to the control group (p < 0.001). FVD and overall PFVD of choriocapillaris were significantly reduced compared to controls in CRVO group (p < 0.001) and PFVD of choriocapillaris was significantly reduced compared to controls in the affected hemi fields in BRVO groups (p < 0.001). OCTA showed vessel density reduction in BRVO and CRVO with main involvement of the deep retinal plexus compared to the superficial retinal plexus due to ischemia that did not recover after intravitreal dexamethasone implant.

Purpose: To investigate the relationship between perfusion of the choriocapillaris (CC) and macular function in eyes with intermediate age-related macular degeneration. Methods: In this prospective, observational, cross-sectional study, macular optical coherence tomography angiography images and multifocal electroretinograms were obtained in 20 eyes with intermediate age-related macular degeneration from 20 patients. The main outcome measures were (1) the percent nonperfused choriocapillaris area (PNPCA), which represents a measure of the total area of CC vascular dropout, and (2) the average size of the CC signal voids, which represent contiguous regions of CC dropout. Furthermore, amplitude and implicit time of multifocal electroretinograms N1 and P1 waves in the two central rings (R1 and R2) were included in the analysis. Results: Of the 20 patients enrolled, only 17 eyes from 17 patients (13 women) were included in this analysis. Three patients were excluded because of poor scan quality. Mean ± SD age was 75.1 ± 7.9 years (range, 62–89 years). The best corrected visual acuity was 0.17 ± 0.13 logarithm of the minimum angle of resolution. In univariate analysis, both the PNPCA and average signal void size were found to have a significant direct relationship with N1 implicit time in the R2 ring (P = 0.006 and P = 0.035, respectively). Neither PNPCA nor the average signal void size was associated with P1 or N1 implicit times in R1. Conclusions: In intermediate age-related macular degeneration eyes, PNPCA and average signal void size are related to N1 multifocal electroretinogram implicit times, which suggests an association between CC perfusion and photoreceptor function.

To assess vessel density of superficial capillary plexus (SCP), deep capillary plexus (DCP) and choriocapillaris (CC) in advanced Stargardt disease (STGD) using optical coherence tomography angiography (OCTA) and correlate these findings with macular function using pattern electroretinogram (PERG) and multifocal electroretinogram (mfERG). Twelve patients (24 eyes) with advanced STGD underwent vessel densities and macular thickness measurements using OCTA. A control group of 24 healthy controls (24 eyes) was chosen for comparison. In the STGD group correlation between vessel density and macular thickness and between macular function and morphologic parameters were evaluated. Whole parafoveal vessel density (VD) of SCP was significantly lower in STGD group compared to the control group (p<0.05). Foveal VD and whole parafoveal VD of the DCP were significantly lower in STGD group compared to the controls (p<0.05). CC was significantly decreased in STGD compared to controls (p<0.05). Foveal macular thickness (MT), full parafoveal MT, and inner limiting membrane (ILM)-inner plexiform layer (IPL) parafoveal MT thickness were decreased in STGD eyes compared to controls (p<0.001). PERG and mfERG were both significantly reduced in STGD compared to controls (p<0.001). A direct correlation was found between full parafoveal MT and vessel density in the STGD group. Patients with advanced STGD showed a reduction of SCP, DCP and CC compared to healthy eyes related to a reduction of total and ILM-IPL macular thickness. These results suggest that both retinal capillaris plexuses and choriocapillaris reduction occur in STDG along with inner and outer retinal thinning.

(1) Background: To evaluate superficial capillary plexus (SCP), deep capillary plexus (DCP), choriocapillaris (CC), perfusion density (PD), and vessel length density (VLD) in macular and near/mid periphery regions in patients with retinitis pigmentosa (RP) using widefield swept source optical coherence tomography angiography (WSS-OCTA). (2) Methods: Twelve RP patients (20 eyes) and 20 age-matched subjects (20 eyes) were imaged with the SS-OCTA system (PLEX Elite 9000, Carl Zeiss Meditec Inc., Dublin, CA, USA). Quantitative analysis was performed in the macular and peripheral regions. The main outcome measures were SCP, DCP, CC, PD, and VLD in central and peripheral areas. (3) Results: Mean visual acuity, central macular thickness, and microperimetry were significantly reduced in RP patients compared to normal subjects (p < 0.05). The perfusion density and VLD of SCP, DCP, and CC were significantly reduced in RP patients compared to normal controls both in the central and peripheral retina (p < 0.05). A significant direct correlation was found in RP patients between PD of the 1.5 mm central retina both in DCP and CC and microperimetry at 4° and 8°. (4) Conclusions: Widefield SS-OCTA shows an impairment of retinal and choroidal perfusion density and vessel length density in central and peripheral retina of RP patients. The reduction of flow features correlates with the macular function.

Purpose: To investigate radial peripapillary capillary (RPC) network in patients affected by retinitis pigmentosa (RP). Methods: Eleven patients (22 eyes) with previous diagnosis of RP and 16 age-matched healthy subjects (16 eyes) were enrolled. The diagnosis of RP was made based on both clinical features and electrophysiological examination. All patients underwent a complete ophthalmologic examination, including optical coherence tomography angiography (OCTA), and visual field (VF). The primary outcomes were the RPC vessel density in the peripapillary and disc areas; the secondary outcomes were the peripapillary retinal nerve fiber layer (RNFL) thickness, and the mean defect (MD) at VF. Results: A total of 19 eyes of 11 RP patients (5 male, 6 female) and 16 eyes of 16 healthy subjects (10 male, 6 female) were included for the analysis. RPC vessel density in the disc area was 46.5±7.1% in the RP group and 45.4±10.6% in the control group (p=0.754). RPC vessel density in the peripapillary area was significantly reduced in the RP group after the comparison with the control group (52.5±5.0% and 57.2±5.1%, respectively, p=0.011). RNFL thickness was 85.9±20.4 μm in the RP group and 104.0±6.4 μm in the control group (p=0.002). RPC vessel density was significantly correlated with RNFL thickness values in RP patients, both in the disc and in the peripapillary area (Rho=0.599 and p=0.007 in the disc area, Rho=0.665 and p=0.002 in the peripapillary area, respectively). Conclusions: We showed that density of RPC is reduced in these patients in the peripapillary area. Moreover, the RPC vessel density correlates with the RNFL thickness.