Superficial Foveal Avascular Zone Area Research Articles

Relationship between morphological changes in the foveal avascular zone of the epiretinal membrane and postoperative visual function

ObjectiveTo investigate the relationship between the preoperative morphology of the foveal avascular zone (FAZ) and postoperative visual function in patients with idiopathic epiretinal membrane (ERM).Methods and analysisThis retrospective study enrolled...

Evaluation of retinal vascular structure after epiretinal membrane surgery by optical coherence tomography angiography.

To evaluate the retinal vascular structure before and after the epiretinal membrane (ERM) surgery by optical coherence tomography angiography (OCTA). Twenty-two eyes with ERM (study eyes) had been evaluated by OCTA for superficial capillary plexus (SCP) and deep capillary plexus (DCP) vessel density (VD) at foveal and parafoveal regions and foveal avascular zone (FAZ) before and after ERM removal surgery. Twenty-two fellow eyes were selected as control group. Preoperative VD of SCP and DCP were significantly lower in ERM eyes than in controls in both foveal and parafoveal areas (p < 0.05, for all). The difference regressed in SCP (fovea: 18.04 ± 3.1 vs 19.98 ± 18 p = 0.002 and parafovea: 47.33 ± 3.54 vs 49.71 ± 28 p = 0.001), but persisted in DCP (fovea: 17.25 ± 3.52 vs 17.57 ± 4.01 p = 0.856 and parafovea: 50.12 ± 4.35 vs 50.93 ± 3.24 p = 0.791) in study eyes, postoperatively. Superficial and deep FAZ areas were significantly smaller in study eyes than controls. Postoperatively, superficial FAZ area enlarged (0.288 ± 0.10 vs 0.307 ± 0.08 p = 0.012), whereas deep FAZ area did not (0.324 ± 0.09 vs 0.338 ± 0.07 p = 0.435). FAZ area was correlated with the best-corrected visual acuity in ERM eyes. Vascular damage in SCP and DCP was demonstrated by OCTA in eyes with ERM. ERM removal surgery mainly improves superficial changes caused by ERM. Changes in deep retinal flow may be associated with visual outcomes after ERM removal surgery.

Analysis of optical coherence angiography in cystoid macular oedema associated with gyrate atrophy.

To evaluate the relationship between superficial, deep foveal avascular zone (FAZ) and foveal cyst areas in eyes with cystoid macular oedema (CMO) associated with gyrate atrophy of the choroid and retina (GA). This is a retrospective collaborative multicenter study of optical coherence tomography-angiography (OCTA) images in GA. Superficial and deep FAZ and foveal cyst were measured using Image J by two independent experts. Values were corrected for myopia magnification. These values were compared with age-matched controls from normative data. Twenty-three eyes from 12 patients with GA and CMO were included in the study. The mean ± standard deviation age was 22 ± 19.7 years, mean Snellen spectacle-corrected visual acuity of 20/70 with mean myopia of 5.7 ± 4.1 dioptres. Qualitatively, no focal occlusion of superficial and deep capillary plexus was noted. Mean superficial FAZ area (0.484 ± 0.317 mm2), deep FAZ area (0.626 ± 0.452 mm2), and foveal cyst area (0.630 ± 0.503 mm2) were significantly larger than superficial and deep FAZ areas in controls of same age range (p < 0.001). Macular cyst area correlated with superficial FAZ area (R = 0.59; p = 0.0057) and more strongly with deep FAZ area (R = 0.69; p < 0.001). The superficial and deep FAZ area in GA-associated CMO were noted to be significantly larger than in controls. It seems that RPE dysfunction leads to foveal cyst enlargement displacing the capillary plexus with resultant enlarged superficial and deep FAZ area.

Evaluation of The Foveal Avascular Zone Alterations Through Optical Coherence Tomography Angiography In Eyes With Retinal Vein Occlusion.

Background: To detect the effectiveness of OCT-A in evaluation of foveal avascular zone (FAZ) alterations in eyes with retinal vein occlusion . Objectives: To investigate the relationship between best-corrected visual acuity (BCVA) and the FAZ in patients with (RVO) evaluated with (OCT-A) in comparison to the unaffected fellow eyes. Patients and Methods: We retrospectively reviewed the medical records of 15 patients with (RVO); BRVO in 8 patients, CRVO in 7 patients) and we considered the unaffected fellow eyes of these patients as a control group, who were evaluated by OCT-A by a 6 mm × 6-mm region scan centered on the fovea and parafoveal area. The (FAZ), and foveal and parafoveal vascular density in superficial and deep vascular plexuses were analyzed. Result: The mean superficial FAZ area (SL FAZ area) measured 0.40mm in the study group and 0.30mm in the control group. The mean deep FAZ area(DL FAZ area) measured 0.46 mm in the study group and 0.35 mm in the control group. The SL FAZ and DL FAZ areas in eyes with RVO were larger than those in control eyes (P = 0.002, P = 0.033).We found a negative correlation between the BCVA and the superficial FAZ area in eyes with RVO (r = _0.42, P = 0.11).We found a negative correlation between the BCVA and deep FAZ area in the control group(r=_0.30, P 0.26). Conclusions: OCT-A allows detecting FAZ enlargement.Also, we found statistically significant negative correlation between FAZ enlargement and BCVA in patients with RVO.

Quantitative measurements with optical coherence tomography angiography in Behçet uveitis.

The aim of this study was to evaluate the quantitative measurements obtained by optical coherence tomography angiography in patients with Behçet uveitis. A total of 22 consecutive patients with Behçet uveitis and 19 age-matched healthy individuals were included in the study. Quantitative analysis of optical coherence tomography angiography images was performed. Comparisons between the patients and the control groups and correlation analysis between optical coherence tomography angiography results and age, visual acuity, duration of uveitis, central macular thickness, and fluorescein angiography scores in the patient group was performed. The mean superficial foveal avascular zone area was 283.040 ± 113.003 µm2 in the patient group and 254.268 ± 75.813 µm2 in the control group (p = 0.821). The mean deep foveal avascular zone area was 317.657 ± 116.225 µm2 in the patient group and 332.954 ± 94.783 µm2 in the control group (p = 0.775). The foveal avascular zone area could not be calculated in eight eyes with macular atrophy in the patient group because of unclear foveal avascular zone borders. Both superficial and deep capillary vessel density in all regions were lower in the patient group than in the control. Superior, inferior, and temporal capillary vessel density were correlated with fluorescein angiography score (Pearson's r = -0.380, 0.392, and -0.384, p < 0.05 in superficial plexus; r= -0.357, -0.401, and -0.321, p < 0.05 in deep plexus, respectively). The foveal avascular zone area was correlated with central macular thickness in both superficial and deep plexus (r= -0.387 and -0.331, p < 0.05, respectively). Recurrent uveitis attacks affecting the macula are associated with a decrease in capillary vessel density and expansion in the foveal avascular zone area in Behçet disease. The qualitative evaluation of the optical coherence tomography angiography findings may be more valuable in patients with macular atrophy.

Posterior vitreous detachment and macular microvasculature in the elderly.

PurposeTo investigate the association between different stages of posterior vitreous detachment (PVD) and macular microvasculature in the elderly.MethodsSwept-source optical coherence tomography (OCT), OCT angiography, and color fundus images of 490 eyes without retinal pathologies of 322 participants aged ≥65 years were evaluated. PVD was classified using enhanced vitreous visualization mode as no apparent PVD (stage 0/1), vitreous adhesions at the fovea and optic disc (stage 2), adhesion at the optic disc (stage 3), or complete PVD (stage 4). Microvascular parameters, including foveal avascular zone (FAZ) and vessel density (VD), were analyzed for their associations with complete PVD. Additionally, the association between PVD and central retinal thickness (CRT) was also addressed.ResultsOverall, 80, 31, 31, and 349 eyes were categorized into stages 0/1, 2, 3, and 4, respectively. Using multivariate mixed-effects model, the mean superficial FAZ area was smaller in stage 4 compared with stages 0–3 (0.29 vs. 0.32 mm2; P = 0.014), and the mean superficial VD was lower in stage 4 compared with stages 0–3 (34.96% vs. 35.24%; P = 0.0089). However, PVD was not significantly associated with deep macular microvascular parameters or CRT.ConclusionsComplete PVD was associated with smaller FAZ area and lower VD in superficial macular microvasculature, while it was not associated with central retinal thickness.

Changes of foveal avascular zone size and correlation between foveal avascular zone size and metamorphopsia before and after idiopathic macular epiretinal membrane surgery

Objective To observe the changes of foveal avascular zone (FAZ) size before and after surgery in idiopathic macular epiretinal membrane (IMEM) eyes and analyze the correlation of FAZ with metamorphopsia. Methods A retrospective case series study. From August 2016 to October 2017, 42 eyes of 38 patients affected with IMEM diagnosed in Central Theater Command General Hospital of Chinese People's Liberation Army were enrolled in this study. All the patients underwent a 25G pars plana vitrectomy (PPV) with IMEM removal and ininternal limiting membrane (ILM) peeling. The BCVA was measured using the international standard visual acuity chart, and the results were converted to the logMAR visual acuity. The severity of metamorphopsia was measured using M-charts. The FAZ areas were evaluated with OCT angiography in both the superficial and deep capillary plexus layers. The central macular thickness (CMT) were assessed with spectral-domain OCT before and after surgery. The logMAR BCVA was 0.61±0.21. The M-score was 0.66±0.38. The CMT of fovea was 337.71±57.63 μm. The FAZ areas in superficial and deep capillary plexus were 0.113±0.037 mm2 and 0.202±0.03 mm2, respectively. The differences in BCVA, M-score and FAZ area before and 1, 3, 6, 12 months after surgery were analyzed by ANOVA. The Spearman rank correlation analysis was performed to investigate the relationship between FAZ areas, visual acuity and metamorphopsia. Results At 12 month after surgery, the FAZ areas in superficial and deep capillary plexus were 0.146±0.021 mm2 and 0.240±0.019 mm2, respectively. Compared with baseline, the the FAZ areas in superficial and deep capillary plexus after surgery significantly increased (F=8.484, 14.346; P<0.001,<0.001). The postoperative logMAR BCVA 0.47±0.19, M-score 0.12±0.22 and CMT 270.60±33.27 μm were significantly improved compared with baseline (F=5.044, 17.763, 13.545; P=0.001, <0.001, <0.001). The preoperative FAZ area in superficial capillary plexus correlated negatively with preoperative M-score (r=-0.816, P<0.001); the preoperative FAZ area in deep capillary plexus correlated negatively with preoperative BCVA and M-score (r=-0.422, -0.882; P=0.005,<0.001). The postoperative FAZ area in superficial capillary plexus correlated negatively with preoperative and postoperative M-score (r=-0.791,-0.716; P<0.001,<0.001). The postoperative FAZ area in deep capillary plexus correlated negatively with BCVA and preoperative and postoperative M-score (r=-0.343, -0.330, -0.732, -0.694; P=0.026, 0.033,<0.001,<0.001). Conclusions PPV with ILM peeling can effectively restore the FAZ areas in superficial and deep capillary plexus, improve the visual acuity and metamorphopsia in patients with IMEM. Both superficial and deep plexus FAZ areas correlated negatively with metamorphopsia, and deep plexus FAZ area also correlated negatively with BCVA. Key words: Macula lutea; Membranes; Vitrectomy; Tomographyoptical coherence; Foveal avascular zone; Metamorphopsia

Factors Affecting the Foveal Avascular Zone Area in Healthy Eyes among Young Chinese Adults.

Purpose To evaluate the influence of systemic and ocular factors on the foveal avascular zone (FAZ) area in young Chinese subjects' healthy eyes. Methods The current observational, cross-sectional study included 344 eyes from 172 healthy individuals (103 women, 69 men). Optical coherence tomography angiography realized with the split-spectrum amplitude-decorrelation angiography (SSADA) algorithm was used to assess the area of superficial FAZ. To determine the related factors and to reveal their potential correlations with the FAZ area, comprehensive examinations including both systemic and ocular ones were executed. Systemic examination involved factors including age, gender, and body mass index, while ocular examination involved factors including BCVA, refractive error, intraocular pressure, axial length (AL), anterior chamber depth, and central corneal thickness. Especially for fundus examination, central macular thickness (CMT), retinal volume, mean retinal thickness, macular blood flow area/vessel density in the superficial retinal layer (SRL) and deep retinal layer (DRL), mean retinal nerve fiber layer (RNFL) thickness, ganglion cell layer (GCL) thickness, C/D rate, rim area, and subfoveal choroid thickness were assessed, using mixed-effects regression models to appropriately account for intereye correlation. Subgroup analyses were performed based on gender and high myopia categories. Results The mean FAZ area was 0.30 ± 0.11 mm2 and varied significantly across gender (P = 0.0024). AL, CMT, and RNFL thickness were found significantly correlated with the FAZ area in the univariate regression analysis (AL, P = 0.0005; CMT, P < 0.0001; and RNFL thickness, P = 0.0461). According to the multivariate results, CMT and macular blood flow in SRL were negatively correlated with FAZ (CMT: P < 0.0001; macular blood flow in SRL: P = 0.00223). Mean retinal thickness, mean GCL thickness, and macular blood flow in DRL were positively correlated with FAZ (mean retinal thickness: P = 0.0005; mean GCL thickness: P < 0.0001; and macular blood flow in DRL: P = 0.0099). Correlation results among these filtered factors and FAZ were more pronounced in non-high-myopic eyes than in high-myopic eyes and had a significant difference when data of male and female subjects were processed separately from each other. Conclusion The present cross-sectional study performed comprehensive systemic and ocular examinations in young Chinese adults and filtered factors affecting FAZ. We indicated that among all the assessed candidate factors, gender, AL, retinal thickness, macular blood flow, RNFL, and GCL thickness affected the FAZ area most significantly. Such findings would facilitate future research concerning the role of FAZ variation in fundus diseases.

RELATIONSHIP BETWEEN ABNORMALITIES OF PHOTORECEPTOR MICROSTRUCTURES AND MICROVASCULAR STRUCTURES DETERMINED BY OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY IN EYES WITH BRANCH RETINAL VEIN OCCLUSION.

To determine whether the size of the foveal avascular zone (FAZ) is significantly correlated with the best-corrected visual acuity (BCVA) and to examine the relationship between the size and microstructural changes of the photoreceptors in eyes with a branch retinal vein occlusion. The medical records of 69 eyes of patients (mean age, 64.6 ± 11.7 years) with a branch retinal vein occlusion were reviewed after the resolution of macular edema. All the patients underwent optical coherence tomography angiography for measurement of the FAZ area and spectral domain optical coherence tomography for determination of microstructural changes of the photoreceptors at the fovea. The superficial and deep FAZ areas in eyes with a branch retinal vein occlusion were 0.39 ± 0.36 mm and 0.63 ± 0.18 mm, respectively, and both were significantly larger than those observed in the fellow eyes (both, P < 0.001). The superficial FAZ area correlated with the posttreatment BCVA (r = 0.285, P = 0.027) but not with any parameters regarding the microstructures of the photoreceptors. Multivariate linear regression analysis showed that the pretreatment BCVA (β = 0.519, P < 0.001) and integrity of the external limiting membrane (β = -0.373, P = 0.001) were independent factors that significantly correlated with the posttreatment BCVA. There was no significant correlation between the FAZ area and microstructural parameters. However, the integrity of the external limiting membrane was significantly correlated with the posttreatment BCVA in eyes with a branch retinal vein occlusion.

DIABETIC MACULAR ISCHEMIA

To examine the relationship between macular microvasculature parameters and functional changes in persons with diabetic retinopathy (DR). Cross-sectional study of 76 eyes with varying levels of DR. Optical coherence tomography angiography (OCTA) quantified superficial and deep perifoveal vessel densities and foveal avascular zone areas. Retinal sensitivity was measured using microperimetry. Optical coherence tomography angiography parameters and retinal sensitivity were correlated. Deep perifoveal vessel density decreased with increasing severity of DR (adjusted mean 51.93 vs. 49.89 vs. 47.96, P-trend = 0.005). Superficial and deep foveal avascular zone area increased with increasing DR severity (adjusted mean: 235.0 µm vs. 303.4 µm vs. 400.9 µm, P-trend = 0.003 [superficial]; 333.1 µm vs. 513.3 µm vs. 530.2 µm, P-trend = 0.001 [deep]). Retinal sensitivity decreased with increasing DR severity (adjusted mean: 25.12 dB vs. 22.34 dB vs. 20.67 dB, P-trend = 0.003). Retinal sensitivity correlated positively with deep perifoveal vessel density (Pearson's ρ = 0.276, P = 0.020) and inversely with superficial foveal avascular zone area (Pearson's ρ = -0.333, P = 0.010). Alterations in retinal microvasculature can be observed with OCTA with increasing severity of DR. These changes are correlated with reduced retinal sensitivity. Optical coherence tomography angiography is useful to detect and quantify the microvasculature properties of eyes with diabetic macular ischemia.

The vascular densities of the macula and optic disc in normal eyes from children by optical coherence tomography angiography.

This study aims to describe the variation and characteristics of vessel density (VD) of the macula and optic disc in the normal eyes of children. This was a retrospective study where subjects aged 5-18years with normal eyes were enrolled. The macula and optic disc were scanned by optical coherence tomography angiography (OCTA). The influences of age, gender, and axial length (AL) on VD were analyzed. A total of 71 normal eyes from 71 subjects were enrolled. For the macula, the mean VD of fovea, parafovea, and perifovea at superficial retina and deep retina were 20.1%, 50.2%, 49.4%, 36.1%, 53.9%, and 48.1%, respectively. The mean foveal avascular zone (FAZ) was 0.277mm2. For optic disc, the mean VD of radial peripapillary capillary (RPC) and inside-disc areas were 51.8% and 51.7%, respectively. Significant differences were found between the superior-hemi and inferior-hemi VD of the superficial retinal parafovea, deep retinal perifovea, and perifovea. The fovea VD of the superficial and deep retina and FAZ areas were different between genders. The inside-disc VD was positively correlated with AL, while other VDs had no significant correlation with age and AL. The parafovea VD of the superficial retina, parafovea, and perifovea of the deep retina had superior-hemi VD; boys had a higher fovea VD and smaller FAZ area than those of girls, the macular VD and peripapillary RPC density were steady for 5-18year-olds. This study provided useful information for furthering the understanding of the development mode of vessel in children and the OCTA clinical applications in children.

Quantitative assessment of the effect of fasting on macular microcirculation: an optical coherence tomography angiography study

AimTo analyse the effect of fasting on the retinal vascular plexus and choriocapillaris structures in healthy subjects via Optical Coherence Tomography Angiography (OCTA).MethodsIn this prospective study, OCTA scans of 98...

Foveal Avascular Zone Area Analysis Using OCT Angiography After Pneumatic Retinopexy for Macula-Off Rhegmatogenous Retinal Detachment Repair

Purpose: Recent publications have reported that the deep capillary plexus (DCP) area of the foveal avascular zone (FAZ) is significantly larger in eyes following pars plana vitrectomy (PPV) for rhegmatogenous retinal detachment (RRD) repair when compared with controls. To the best of the authors’ knowledge, there have been no publications on the evaluation of the macular microvasculature using optical coherence tomography angiography (OCTA) in post–pneumatic retinopexy (PnR) eyes. Therefore, the purpose of this study was to investigate FAZ-area changes following PnR. Methods: This retrospective cohort included 19 patients with macula-off RRD who underwent PnR repair. Each patient’s fellow eye was used as a control. The FAZ area in the superficial capillary plexus and DCP was investigated with OCTA and the areas were measured by 2 masked graders. Results: Both superficial (PnR: 0.22 [0.16-0.35] vs control: 0.24 [0.18-0.34] mm2; P = .715) and deep (PnR: 0.56 [0.51-0.76] vs control: 0.7 [0.59-0.89] mm2; P = .105) FAZ areas were not significantly different between eyes. Conclusions: Our results suggest that the lack of FAZ-area enlargement after PnR repair may indicate that there is less ischemic damage to the retinal capillary plexus in the fovea when compared with that described in the literature for PPV. The PIVOT trial demonstrated that PnR is associated with superior visual acuity and less metamorphopsia when compared with PPV at 1 year. The results of the current study may provide insight into the potential advantages of PnR. Further studies are needed to elucidate how the macular microvasculature is affected after RRD and to clarify how the FAZ area changes following PnR and PPV.

Automated quantification of foveal avascular zone and vascular density in Behçet's disease.

To measure the vascular density (VD) and foveal avascular zone (FAZ) area in patients with Behçet's disease (BD) obtained by optical coherence tomography angiography (OCTA). VD and FAZ area in the deep and superficial retinal vascular networks were measured in all eyes. Thirty BD and 31 control subjects were included in the study. The mean overall VD measured in the entire scan was lower in BD compared with control group in both the superficial (49.52 ± 6.54 vs 53.57 ± 2.87%, respectively; p = 0.003) and deep (53.44 ± 7.44 vs 58.41 ± 3.01%, respectively; p = 0.002) areas. The FAZ in the BD group was significantly increased at the level of the superficial (0.52 ± 0.67 vs 0.28 ± 0.1mm2, respectively; p = 0.05) and deep (0.91 ± 1.25 vs 0.39 ± 0.14mm2, respectively; p = 0.024) areas compared with those of the control group. The deep and the superficial FAZ areas were positively correlated with disease duration and negatively with VA. In the patients with BD, OCTA showed decreased VD in both the superficial and deep retinal vascular networks. Besides, the VA was correlated with the VD and FAZ.

Foveal Avascular Zone in Hypertension as Measured by Optical Coherence Tomography Angiography

Purpose: To investigate the Foveal Avascular Zone (FAZ) area in patients with arterial hypertension using optical coherence tomography angiography (OCT-A).Material and methods: The study was permormed at the School Clinic of UNIFACISA and at the Eye Care Center. It was included 21 hypertensive patients (study group) and 19 individuals without hypertension (control group). It was excluded patientes with diabetes or glaucoma. The measurement of the FAZ areas was performed by the DRI OCT-1Triton/Plus. For the quantitative variables, the results were expressed by their means and standard deviations. Qualitative variables were expressed by their absolute and relative frequencies. Student’s t-test was used to verify differences between means and Fisher’s exact test for differences between frequencies. For evaluating the correlation between the superficial and deep plexus areas, the Pearson correlation test was used. P value ≤ 0.05, rejected the null hypothesis. The research was approved by the Ethics Committee of the Medical School from Campina Grande -UNIFACISA and all individuals signed the free and informed consent form.Results: The means of the superficial FAZ of both eyes was significantly higher in the study group (right eye 410.7 ± 160.7 μm2 - 319.1 ± 108.2 μm2 - p = 0.0433); (left eye: 405.4 ± 144.8 μm2 versus 309.4 ± 87.7 μm2- p = 0.0174). The means of the deep FAZ areas of the right and left eyes were similar between the study and control groups (right eye: 559.6 ± 253.28 μm2 versus 605.1 ± 226.8 μm2 - p = 0.5548); (left eye: 673.2 ± 170.8 μm2 versus 585.6 ± 171.2 μm2 - p = 0.1142). The relationships between the superficial and deep plexus areas of both eyes showed a weak correlation between the two plexuses. (r = 0.4734), left eye (r = 0.2287), study group - right eye: (r = 0.4374), left eye (r = 0.3580).Conclusion: The area of superficial FAZ of the right and left eyes was significantly higher in the hypertensive patients. The deep FAZ area of both eyes, however showed similar mean areas between the study and control groups.

Correlation between foveal avascular zone size and foveal morphology in patients with idiopathic macular epiretinal membrane

Objective To analyze the correlation between foveal avascular zone (FAZ) size and foveal morphology in patients with idiopathic macular epiretinal membrane (IMEM) using OCT angiography (OCTA). Methods A retrospective case series study contained of 54 eyes of 54 patients affected with IMEM (IEM group) and 50 eyes of 50 normal persons as the control group. The BCVA was measured using the international standard visual acuity chart, and the results were converted to the logMAR visual acuity. The FAZ areas were evaluated with OCTA in both the superficial and deep capillary plexus layers by using 3 mm×3 mm images of the macular. The central macular thickness (CMT), inner retinal layer thickness (IRT), outer retinal layer thickness (ORT), subfoveal choroidal thickness (SFCT), and the status of ellipsoid zone (EZ) were assessed with spectral-domain optical coherence tomography. The differences of FAZ areas between the two groups were analyzed. The correlative analysis was performed to investigate the relationship between areas and foveal morphology. Results Compared with control group, the FAZ area in superficial and deep capillary plexus in the IMEM group were significantly smaller (t=−29.095, −28.743; P<0.001, <0.001); the mean CMT, IRT, ORT and SFCT were significantly thickening in the IMEM group (Z=−8.784, −8.524, −7.709, −7.535; P<0.001,<0.001, <0.001, <0.001). In the IMEM group, the FAZ area in superficial capillary plexus correlated inversely with the CMT, IRT, and the integrity of EZ (r=−0.464, −0.536, −0.293; P<0.001, <0.001, 0.039), no significant correlation of superficial plexus FAZ areas with ORT and SFCT (r=−0.218, −0.165; P=0.172, 0.157). The FAZ area in deep capillary plexus correlated inversely with the CMT, IRT, and the integrity of EZ (r=−0.306, −0.694, −0.468; P=0.037, <0.001, <0.001), no significant correlation with ORT and SFCT (r=−0.242, −0.227; P=0.079, 0.094). Conclusions The FAZ areas is significantly decreased in IMEM eyes compared with normal eyes. Both superficial and deep FAZ area are correlated with the CMT, IRT, and the integrity of EZ. Key words: Macula lutea; Membranes; Tomography, optical coherence; Foveal avascular zone

Superficial foveal avascular zone area changes before and after idiopathic epiretinal membrane surgery.

To investigate the foveal morphological changes and foveal avascular zone (FAZ) area before and after epiretinal membrane (ERM) surgery. Twenty-two eyes with treatment-naive ERM were included in this retrospective study. The central foveal thickness (CFT) and FAZ area were measured via swept-source optical coherence tomography (SS-OCT) and OCT angiography pre- and postoperatively. The unaffected fellow eyes were used as controls. The preoperative superficial FAZ area was significantly smaller in patients (0.08±0.04 mm2) than in controls (0.33±0.09 mm2; P<0.001). The postoperative superficial FAZ (0.12±0.06 mm2) area was significantly greater than the preoperative area (P<0.001). The preoperative superficial FAZ area was strongly negatively correlated with CFT (P<0.001, rho=-0.763). ERM induced significant foveal morphological changes and reduction of the superficial FAZ area. Foveal thickness was restored and FAZ area increased postoperatively. However, the process is rather slow and the recovery is incomplete.

OCT Angiography in Young Children with a History of Retinopathy of Prematurity

To describe the size and appearance of the foveal avascular zone (FAZ) in the superficial and deep plexus in young children with treated or spontaneously regressed retinopathy of prematurity (ROP), in comparison with age-matched controls and young adults, as seen with OCT angiography (OCTA), and to compare these parameters with foveal classic OCT images and visual function. Prospective, cross-sectional study. Twenty-five children with treated or spontaneously regressed ROP (mean 5.0±0.8 years) compared with 15 healthy term-born age-matched children and 20 healthy adults. OCTA was performed using a DRI OCT Triton (Swept Source OCT, Topcon, Oakland, NJ). The best-quality images of 1 eye per patient were analyzed. Superficial FAZ and deep FAZ were analyzed separately. Single-scan OCTs were performed using a Spectralis SD-OCT (HRA+OCT, Heidelberg Engineering, Heidelberg, Germany). The foveal pit characteristics and the degree of macular developmental arrest (MDA), defined as the ratio of the outer nuclear layer+ external limiting membrane (ONL+) and the inner retinal layers in the fovea (ONL+/IRL-ratio), were analyzed with a custom-made automated layer segmentation tool (DiOCTA, copyright by Justus-Liebig-University, Giessen, Germany). Visual acuity (VA) was tested with Early Treatment of Diabetic Retinopathy Study letter charts. The ONL+/IRL-ratio, superficial FAZ area, deep FAZ area, foveal parameters, and VA. Foveal pit depth and area were significantly reduced in both treated and spontaneously regressed ROP, whereas the foveal diameter was comparable in all groups. OCTA showed a significantly narrowed superficial FAZ in eyes with treated and spontaneously regressed ROP. In contrast, the deep FAZ was of comparable size in all groups. A reduced superficial FAZ significantly correlated with reduced ONL+/IRL-ratio, and thus the degree of MDA. In treated and spontaneously regressed ROP, reduced superficial FAZ and MDA correlated significantly with diminished VA. OCTA is feasible in young children with a history of ROP and without neurodevelopmental delay. It allows detecting a decreased superficial FAZ size noninvasively. A small superficial FAZ, reduced ONL+/IRL-ratio as a measure of MDA, and reduced VA are concurrent factors in preterm children who are otherwise neurologically normal.

Foveal Avascular Zone Area Changes Analyzed Using OCT Angiography after Successful Rhegmatogenous Retinal Detachment Repair

ABSTRACTPurpose: To investigate foveal avascular zone (FAZ) area after surgery in patients with rhegmatogenous retinal detachment (RRD) that involved or uninvolved the macula, and to evaluate the correlation between FAZ area and visual outcomes using swept-source optical coherence tomography angiography (OCTA).Materials and Methods: This retrospective case–control study included 34 eyes (34 patients) with recent onset RRD that were successfully repaired with a single, uncomplicated surgical procedure (pars plana vitrectomy with gas tamponade). The changes of FAZ area were examined by OCTA after surgery. The unaffected fellow eye was used as a control for additional comparison.Results: Both superficial and deep FAZ area were significantly larger in the macula-off group (superficial: 0.374 ± 0.112, deep: 0.702 ± 0.193 mm2) than in the macula-on group (superficial: 0.282 ± 0.105, deep: 0.543 ± 0.114 mm2) following surgery. The deep FAZ area was also markedly larger in the macula-off group than in the control group (0.532 ± 0.124 mm2). Correlation analyses revealed that both superficial (ρ = 0.555, P = 0.015) and deep FAZ (ρ = 0.616, P = 0.005) areas were negatively correlated with postoperative best-corrected visual acuity in the macula-off RRD group.Conclusions: The FAZ area enlargement after successful surgical repair in macula-off RRD eyes may indicate that there is an ischemic damage to retinal capillary plexus in fovea.

Macular Perfusion Parameters in Different Angiocube Sizes: Does The Size Matter in Quantitative Optical Coherence Tomography Angiography?

To investigate the macular quantitative parameters interchangeability of three different optical coherence tomography angiography (OCT-A) angiocubes (i.e., 3 × 3, 6 × 6, and 12 × 12 mm) on healthy subjects and patients affected by diabetic retinopathy (DR) and to assess the interrater reliability of such indices across the different scan protocols. Retrospective study involving 20 eyes of healthy subjects and 20 eyes with DR. All eyes underwent swept-source OCT-A with 3 × 3-, 6 × 6-, and 12 × 12-mm angiocubes centered on the fovea. Foveal avascular zone (FAZ) area and vessel density on 3 × 3-, 6 × 6-, and 12 × 12-mm macular scans were calculated by three independent operators at all retina, superficial, deep, and choriocapillary vascular layers. Interchangeability and interrater reliabilities were estimated using intraclass correlation coefficient (ICC). Interscan reproducibility of FAZ area was very strong (ICC > 0.85) at every plexus. On the contrary, vessel density values significantly varied across different scan sizes (ICC < 0.51). Intrascan interrater reliability was high for all retina and superficial FAZ areas, while it was satisfactory at deep capillary plexus only for 3 × 3-mm scan. FAZ area at all plexuses is a robust parameter even if calculated on angiocubes with different size. However, interrater reliability is higher when measured in smaller scans. Conversely, vessel density results depend on the size of angiocube, although their interrater reliability is extremely high. Studies involving OCT-A should take into consideration that scan size may influence macular perfusion parameters and interrater reliability.