Evaluation of pseudophakic cystoid macular edema using optical coherence tomography angiography

Evaluation of Radial Peripapillary Capillary Density in G6PD Deficiency: An OCT Angiography Pilot Study

Glucose-6-phosphate-dehydrogenase (G6PD) deficiency is an inherited enzymatic disorder causing hemolytic anemia. The purpose of this pilot study was to compare vascular density (VD) values of the radial peripapillary capillary (RPC) plexus in G6PD-deficient and G6PD-normal men, using optical coherence tomography angiography (OCTA).

METHODS

46 G6PD-deficient men and 23 age-matched male controls were included. A complete ophthalmological evaluation, consisting of slit-lamp biomicroscopy, best-corrected visual acuity, intra-ocular pressure measurement, structural optical coherence tomography, and OCTA scanning of the optic nerve head, was performed. The en-face angioflow images were carefully analyzed and the VD values of the RPC plexus were measured using the AngioAnalytics™ software embedded in the OCTA device. Medical conditions, including systemic hypertension, hypercholesterolemia, and diabetes mellitus, were also investigated.

RESULTS

G6PD-deficient eyes showed higher values of VD in all peripapillary sectors, but a statistical significance (p = 0.03) was reached only in the infero-temporal sector. There were no significant differences in terms of hypercholesterolemia, systemic arterial hypertension, and diabetes mellitus between the two study groups.

CONCLUSION

Results show that VD values of the RPC plexus are higher in G6PD-deficient men than in G6PD-normal subjects, but a statistically significant difference was found only in the inferior temporal sector. Overall, our preliminary findings support the hypothesis that the RPC layer of G6PD-deficient men consists of a denser vascular network, which may contribute to offering protection against ocular atherosclerotic vasculopathies.

Macular capillary displacement in exudative and tractional macular oedema: a multimodal imaging study and pathophysiological hypothesis

PURPOSE

This study aims to describe vessel density differences in tractional versus exudative macular oedema with the aid of novel custom imaging analysis techniques.

METHODS

In this retrospective study, patients with exudative and tractional macular oedema were imaged with optical coherence tomography (OCT), en-face OCT, OCT-angiography and fluorescein angiography. A novel image processing algorithm was developed to extrapolate data from the vessel density maps.

RESULTS

Forty-one eyes of 36 patients were included. A total of 30 control eyes comprised the control group. At the deep capillary plexus (DCP), exudative eyes presented with a vessel density of 62.12 ± 5.7, significantly higher if compared to both tractional lamellar macular hole (57.6 ± 4.6, p = 0.004) and controls (52.07 ± 2.3, p < 0.001). At the superficial capillary plexus (SCP), there were no differences in vessel density between exudative eyes (51.9 ± 4.4) and both the tractional lamellar hole (54.9 ± 3.1, p = 0.083) and the control (51.72 ± 2.2, p = 0.083) groups. In the exudative subgroup, there was a direct correlation between areas of low flow and those of high flow at both the DCP and SCP (p = 0.001 and p = 0.042, respectively).

CONCLUSIONS

Intraretinal expansion of fluid may cause the displacement of the surrounding retinal parenchyma and capillaries.

VISUAL IMPAIRMENT AND MACULAR VASCULAR REMODELING SECONDARY TO RETROGRADE MACULOPATHY IN RETINAL DETACHMENT TREATED WITH SILICON OIL TAMPONADE

PURPOSE

To assess the frequency of macular cysts (MCs) in retinal detachment treated with silicone oil and evaluate their impact on visual acuity and macular vascularization using optical coherence tomography-angiography.

METHODS

Forty-three eyes of 41 patients treated with silicone oil for retinal detachment were retrospectively studied. Best-corrected visual acuity and 6- × 6-mm optical coherence tomography-angiography examination at least 3 months after silicone oil removal were reviewed. In eyes with MCs, cyst area was measured on the en face optical coherence tomography-angiography image using ImageJ. Density of superficial capillary plexus and area of superficial foveal avascular zone were generated by the optical coherence tomography-angiography. Density of deep capillary plexus and deep foveal avascular zone area were measured using ImageJ.

RESULTS

Twenty-five eyes (58%) presented with MCs. Cysts were exclusively located in the inner nuclear layer in 60% of cases. Mean best-corrected visual acuity in the MC group was lower than that of the non-MC group (P = 0.012). Macular cyst area negatively correlated with best-corrected visual acuity (P = 0.0201). Density of superficial capillary plexus was higher in the MC group (P < 0.0001), whereas area of superficial foveal avascular zone was lower (P < 0.0001). Macular cyst area negatively correlated with density of deep capillary plexus (P < 0.001).

CONCLUSION

The incidence of INL-MCs after silicone oil removal is high. These are associated with impaired vision and macular vascular remodeling. We highlight their similarity with the "retrograde maculopathy" phenomenon.

QUANTITATIVE OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY FEATURES OF INACTIVE MACULAR NEOVASCULARIZATION IN AGE-RELATED MACULAR DEGENERATION

PURPOSE

To compare quantitative optical coherence tomography angiography parameters between treatment-naïve quiescent macular neovascularizations (MNVs) and previously treated nonexudative Type 1 MNVs, in patients with age-related macular degeneration.

METHODS

The eyes included in the study were analyzed by fluorescein angiography, indocyanine green angiography, spectral-domain optical coherence tomography, and optical coherence tomography angiography. According to their medical history and multimodal imaging evaluation, Type 1 MNVs were divided into 2 groups: 1) treatment-naïve quiescent MNVs; 2) previously treated nonexudative Type 1 MNVs. Quantitative optical coherence tomography angiography parameters, including perfusion density (PD), fractal dimension (FD), and lacunarity (LAC) were calculated. Receiver operating characteristic curves, showing the ability of PD, FD, and LAC to discriminate between the two MNV groups, were built.

RESULTS

Twenty-two eyes with treatment-naïve quiescent MNVs and 20 eyes with MNVs previously treated nonexudative Type 1 MNVs were analyzed. Mean FD and LAC were statistically different between the two study groups (P < 0.05). Lacunarity showed the best discrimination ability, followed by FD and PD (area under curve = 0.83, 0.78, 0.62, respectively).

CONCLUSION

Results suggest that FD and LAC may be useful optical coherence tomography angiography biomarkers to objectively discriminate inactive MNVs with different prognosis, such as treatment-naïve quiescent MNVs and previously treated nonexudative Type 1 MNVs, in age-related macular degeneration patients.

Pharmacotherapeutic management of macular edema in diabetic subjects undergoing cataract surgery

INTRODUCTION

Cataracts and diabetes are widespread pathologies that are of growing concern to the global population. In diabetic patients who have had cataract surgery, the worsening of preexisting diabetic macular edema or occurrence of pseudophakic cystoid macular edema are common causes of visual impairment even with the most advanced surgical techniques available today for phacoemulsification.

AREAS COVERED

In this review, the authors assess the available literature to evaluate and compare different drugs, with the aim of establishing the best pharmacological strategies for the prevention and treatment of macular edema in diabetic patients undergoing cataract surgery.

EXPERT OPINION

Guidelines for the optimal management of diabetic macular edema in conjunction with cataract surgery or treatment of pseudophakic cystoid macular edema in diabetic patients are still lacking. To treat these conditions, clinicians need to understand the pharmacokinetics, posology, and efficacy of available drugs: topical non-steroidal anti-inflammatory drugs (NSAIDs), intravitreal anti-vascular endothelial growth factors (VEGFs), and both topical and intravitreal steroids. Diabetic patients undergoing cataract surgery should receive topical NSAIDs to prevent pseudophakic cystoid macular edema. Intravitreal anti-VEGFs and steroids, in association with cataract surgery, are indicated for patients with preexisting diabetic macular edema or those at high risk of macular edema after surgery.

Early retinal and choroidal OCT and OCT angiography signs of inflammation after uncomplicated cataract surgery

PURPOSE

To evaluate, by means of optical coherence tomography (OCT) and OCT angiography (OCTA), early retinal, choroidal and macular perfusion changes induced by a local inflammatory reaction secondary to uncomplicated cataract surgery.

METHODS

Selected eyes undergoing cataract surgery were enrolled in a prospective study. OCT and OCTA were performed before cataract surgery (T0) and at day: 1 (T1), 7 (T7), 30 (T30) and 90 (T90). Inner (IR) and outer retinal (OR) volumes, choroidal volume, hyper-reflective retinal spots (HRS) in IR and OR changes were measured at OCT. Macular perfusion was analysed in superficial (SCP), intermediate (ICP) and deep retinal capillary plexuses (DCP).

RESULTS

Nine eyes of nine selected patients were consecutively enrolled. Mean IR volume changed after surgery (p=0.0001), increasing progressively from 4.391±0.231 mm³ at T0 to 4.573±0.241 mm³ at T30, p=0.0002. Both mean OR and choroidal volume increased, mainly at T30, but not significantly (p=0.4360 and p=0.2300, respectively). Mean HRS changed during follow-up, increasing at first in IR and later in OR (at T1 and T7, respectively, both p<0.0001). Macular ICP and DCP perfusion increased at T1, whereas macular SCP perfusion did not change. At T90, all OCT and OCTA parameters had almost reached baseline levels.

CONCLUSIONS

The increase of HRS at first in IR and later in OR seems to confirm their inflammatory nature. Early OCTA changes (underline) underscore a selective susceptibility of DCP and ICP to a localised inflammatory reaction induced by cataract surgery.