Francesca Guidolin

Fundus autofluorescence and microperimetry in progressing geographic atrophy secondary to age-related macular degeneration

Purpose To prospectively analyse microperimetry, standard short-wavelength fundus autofluorescent (SW-FAF) and near infrared-wavelength FAF (NIR-FAF) changes in eyes with geographic atrophy (GA) secondary to age-related macular degeneration. Methods Twenty consecutive eyes (14 patients) affected by GA were enrolled. Repeated microperimetric examinations and FAF images were obtained over a mean follow-up period of 12.3±4.5 months. Results GA area was always wider on NIR-FAF versus SW-FAF images (5.05±2.40 mm2 vs 4.45±2.41 mm2, p=0.005 baseline; 5.78±2.87 mm2 vs 5.21±2.77 mm2, p<0.0001 follow-up). Mean retinal sensitivity significantly decreased during follow-up from 7.68±3.92 dB to 6.71±4.37 dB (p=0.0013). 47.3% of the relative dense scotomas (≤5 dB) progressed to dense scotoma (0 dB). Retinal areas showing relative dense scotoma and characterised by hypo-SW-FAF or hyper-NIR-FAF at baseline had a higher risk of evolving to dense scotoma compared with normo-FAF and hyper-FAF on SW-FAF (OR=2.62 and 2.77, respectively), or normo-FAF at NIR-FAF (OR=2.96). Conclusions SW-FAF, compared with NIR-FAF, underestimates GA area at baseline and at follow-up. The enlargement rate of progression based on NIR-FAF is not greater than on SW-FAF. Different SW-FAF and NIR-FAF patterns show different relative risk of progression from relative to dense scotoma. Microperimetry, SW-FAF and NIR-FAF should be combined to obtain adequate morphological and functional prospective information.

Microperimetry, fundus autofluorescence, and retinal layer changes in progressing geographic atrophy

OBJECTIVE To analyze correlation among microperimetry, inner and outer retinal layers, and fundus autofluorescence (FAF) changes in eyes with progressing geographic atrophy (GA) secondary to age-related macular degeneration. METHODS Microperimetry, spectral-domain optical coherence tomography (SD-OCT), standard short-wavelength FAF (SW-FAF), and near-infrared-wavelength FAF (NIR-FAF) were performed for all patients at both baseline and follow-up visits. FAF pattern, integrity of photoreceptor inner segment/outer segment (IS/OS) junction, total retinal thickness (RT), inner retinal layers (IRL), and outer retinal layers (ORL) thickness changes of every microperimetry extrafoveal tested point were analyzed. RESULTS A total of 366 microperimetry tested points were analyzed (6 patients, 7 eyes). Mean retinal sensitivity significantly decreased (p = 0.0149), and the percentage of dense scotomas significantly increased (p = 0.0125). Mean RT and mean ORL thickness significantly decreased (both p < 0.0001). Mean IRL thickness significantly increased (p = 0.0001). The decrease of ORL thickness was inversely correlated to the IRL thinning (rho = -0.710). FAF pattern at baseline was correlated to RT and ORL thickness (both p < 0.0001) and was significantly correlated to the risk to evolve to dense scotoma during follow-up (p = 0.0001 at SW-FAF, p < 0.0001 at NIR-FAF). Tested points showing at baseline the loss of photoreceptor IS/OS junction had a greater risk for evolving to dense scotoma compared with those with intact photoreceptor IS/OS junction (odds ratio 3.56, 95% CI 2.41-5.27). CONCLUSIONS Retinal sensitivity changes are correlated to IRL and ORL thickness changes, and to photoreceptor IS/OS junction integrity. FAF patterns remain a relevant factor in predicting GA evolution. Microperimetry, SW-FAF and NIR-FAF, and SD-OCT should be combined to obtain adequate morphologic and functional prospective information.

Progressing geographic atrophy: choroidal thickness and retinal sensitivity identify two clinical phenotypes

Purpose To analyse changes in choroidal thickness and retinal sensitivity (Se) in patients with geographic atrophy (GA) with or without choroidal neovascularisation (CNV) in the fellow eye. Participants Patients with bilateral GA (B-GA group) and patients with unilateral GA and CNV in the fellow eye (U-GA group) were followed every 6 months, and enhanced depth imaging optical coherence tomography (OCT), blue and near infrared-wavelength fundus autofluorescence (B- and NIR-FAF), and microperimetry were evaluated. Methods GA area, choroidal thickness, and Se were measured in the eye with GA at baseline and every 6 months up to the last follow-up visit. Results 19 patients (8 in the B-GA group (16 eyes) and 11 in the U-GA group (11 eyes)) were studied. The mean±SD follow-up was 1.66±0.71 years (range 0.74–2.60 years) in the U-GA group, and 1.51±0.86 years (range 0.58–2.95 years) in the B-GA group (p=0.6766). Mean GA area was not significantly different between groups at baseline (p=0.4118 in the B-FA and p=0.6806 in the NIR-FAF) or at follow-up (p=0.5734 in the B-FAF and p=0.8945 in the NIR-FAF). Mean GA area significantly increased in both groups during follow-up (p=0.0050 for B-FAF and p=0.0052 for NIR-FAF in the U-GA group; p=0.0049 for B-FAF and p=0.0072 for NIR-FAF in the B-GA group). Choroidal thickness was significantly greater in the B-GA group compared with the U-GA group both at baseline (mean choroidal thickness 170.5±78.5 μm vs 129.1±36.1 μm; p=0.0371) and at last follow-up (173.2±86.1 μm vs 123±32.1 μm; p=0.0340). During follow-up mean choroidal thickness significantly decreased only in the U-GA group (p=0.0276); conversely mean Se significantly decreased only in B-GA group (p=0.0405). Conclusions During follow-up, changes in Se and choroidal thickness differed in patients with GA with or without CNV in the fellow eye. These results identify at least two GA phenotypes, in which the development and progression of GA may be primarily due to different pathophysiologic mechanisms.

Microperimetry Features of Geographic Atrophy Identified With En Face Optical Coherence Tomography.

IMPORTANCE Progressive geographic atrophy (GA) of the retinal pigment epithelium leads to loss of central vision. To identify GA in age-related macular degeneration and assess treatment, correlation of function observed on microperimetry with structure observed on optical coherence tomographic (OCT) images may be of value. OBJECTIVE To characterize the microperimetric function of GA as identified from en face OCT imaging. DESIGN, SETTING, AND PARTICIPANTS In a case-series study, 20 patients (22 eyes) entered the study at the University of Padova according to preplanned conditions. From March 1 to July 30, 2014, en face OCT images were obtained at the outer retinal layer and choroidal layer levels. The microperimetry sensitivity map was superimposed on the en face OCT images, which had been used to measure GA areas. Relative and dense scotoma rates were calculated in the GA areas. After data collection, the study eyes were divided into 3 groups according to the macular residual mean sensitivity. MAIN OUTCOMES AND MEASURES Retinal sensitivity measured by microperimetry within areas of GA identified by en face OCT images. RESULTS Twenty patients (5 men and 15 women) were included in the study, with a mean (SD) age of 79.5 (7.0) years (range, 69-98 years). Macular residual mean retinal sensitivity was less than 5 dB in 7 eyes (group 1), 5 to 10 dB in 9 eyes (group 2), and greater than 10 dB in 6 eyes (group 3). Mean (SD) GA area differed among the groups at the outer retinal (13.13 [5.03] mm2 [range, 5.75-21.04 mm2] in group 1; 7.80 [3.25] mm2 [range, 3.31-13.52 mm2] in group 2; and 3.94 [2.35] mm2 [range, 1.46-7.90 mm2] in group 3; P = .001) and choroidal (11.83 [5.55] mm2 [range, 4.55-22.14 mm2] in group 1; 7.00 [4.29] mm2 [range, 0.90-13.83 mm2] in group 2; and 3.27 [2.29] mm2 [range, 0.91-7.23 mm2] in group 3; P = .007) layer levels. Mean (SD) GA area imaged at the outer retinal layer level was significantly larger than that imaged at the choroidal level in group 3 (difference, 0.67 mm2; 95% CI, 0.31-1.03 mm2; P = .005), but not in groups 1 or 2. Mean (SD) rate of relative scotoma was significantly higher in the GA area imaged at the outer retinal layer level than at the choroidal level in group 3 (47.70% [31.30%] [range, 13.60%-100%] vs 34.00% [37.30%] [range, 0%-100%]; difference, 13.74%; 95% CI, 3.84%-23.63%; P = .02), but not in groups 1 or 2. CONCLUSIONS AND RELEVANCE In the early stage of GA, when retinal sensitivity is relatively good, these data suggest that the GA area imaged on en face OCT at the outer retinal level correctly detects the wide functional degenerative involvement of the photoreceptors. These findings provide novel data that correlate function and structure, which may be of value when assessing treatments that might prevent or reduce the rate of growth of GA.

MORPHOFUNCTIONAL EVALUATION IN DOME-SHAPED MACULA: A MICROPERIMETRY AND OPTICAL COHERENCE TOMOGRAPHY STUDY

Purpose: To investigate retinal sensitivity (Se) in dome-shaped macula (DSM) using microperimetry and to correlate functional findings to specific spectral domain optical coherence tomography features. Methods: Patients affected by DSM in at least 1 eye were consecutively enrolled in a prospective, cross-sectional study. All studied eyes performed best-corrected visual acuity measurement, microperimetry to assess Se and optical coherence tomography to investigate DSM pattern and to measure bulge height and retinal and choroidal thicknesses. Results: Fifty-three eyes of 29 patients were studied. Dome-shaped macula was vertically oriented (V-DSM) in 23 (43.4%), symmetric (S-DSM) in 17 (32.1%), and horizontally oriented (H-DSM) in 13 eyes (24.5%). Foveal subretinal fluid was present in 29/53 (54.7%) cases; it correlated to the bulge height (P < 0.0001) and determined a reduction of Se (P < 0.0001) not of best-corrected visual acuity (P = 0.7105). Mean Se was 13.9 ± 3.2 dB. Microperimetry parameters did not differ among the different DSM patterns. However, Se was significantly impaired if foveal subretinal fluid was present in V-DSM and in S-DSM, but not in H-DSM (V-DSM: P < 0.0001; S-DSM: P = 0.0252; H-DSM: P = 0.5723). In H-DSM, inferior choroidal thickness was thicker in cases with foveal subretinal fluid compared with those without it (P = 0.0363). Conclusion: In DSM, Se evaluation better reflects the central functional impairment than best-corrected visual acuity, particularly when some optical coherence tomography features, such as foveal subretinal fluid and higher bulge height, are present.

Early OCT angiography changes of type 1 CNV in exudative AMD treated with anti-VEGF

Aims To investigate, with optical coherence tomography angiography (OCTA), short-term changes of type 1 choroidal neovascularisation (CNV), secondary to exudative age-related macular degeneration, after anti-vascular endothelial growth factor (VEGF) treatment. Methods Patients affected by type 1 CNV treated with intravitreal anti-VEGF were consecutively enrolled. All patients underwent OCTA examination before and 48 hours after anti-VEGF treatment. Quantitative and qualitative vascular and morphological macular changes were evaluated. Results Sixteen eyes were included (11 treated with aflibercept and 5 with ranibizumab). Both CNV mean area and pigment epithelium detachment significantly reduced (p=0.0004 and p=0.0007, respectively) after treatment. Cystoid macular oedema (four eyes) decreased in all cases. Neuroretinal detachment (13 eyes) decreased in 85% of cases (11 eyes). Fine CNV vessels density decreased in 75% (12 eyes), whereas larger CNV vessels density remained stable in 66.7% (10 eyes), choroidal flow void signal (7 eyes at baseline) increased in 42.9% (3 eyes) of them and remained stable in 57.1% (4 eyes). Interoperator reproducibility for OCT examination was good for all measurements (intraclass correlation coefficient>0.65). Conclusion Early remodelling of type 1 CNV network after treatment may be non-invasively and reproducibly analysed by means of OCTA. Choroidal perfusion impairment, choroidal flow void signal, surrounding CNV may change during treatment.