Multimodal imaging in multiple evanescent white dot syndrome and new insights in pathogenesis

PURPOSE

To report the multimodal imaging in multiple evanescent white dot syndrome (MEWDS) during the acute and convalescent stages in order to better understand the focus of the inflammatory process.

METHODS

Retrospective cohort study of 4 patients with MEWDS. Each patient underwent: enhanced depth imaging-optical coherence tomography (EDI-OCT), fundus autofluorescence (FAF), fluorescein angiography (FA), indocyanine green angiography (ICGA) and en-face OCT and OCT angiography (OCT-A). Choroidal subfoveal thickness (CST) was measured manually. All patients were studied in the acute stage and convalescent stage after disappearance of OCT abnormalities and resolution of visual symptoms.

RESULTS

Four MEWDS patients with a mean age of 23.5years were studied (range: 16-33years). Two patients were women. Initial mean visual acuity (VA) was 80.25 ETDRS. Final mean VA was 84.25 ETDRS. OCT imaging showed disruption of the ellipsoid zone and a slightly elevated RPE layer with overlying hyperreflective material, all of which corresponded to hyperautofluorescent FAF lesions. FA revealed multiple hyperautofluorescent lesions, correlated with hypocyanescent spots on the late ICGA. OCT-A showed normal superficial and deep retinal capillary plexus as well as choriocapillaris. The disease was self-limited in all the cases, with a mean time of 9weeks to resolution (range: 4-16).

CONCLUSION

The pathophysiology of MEWDS is still debated. We believe that there is still not enough evidence to implicate the outer retina as the primary cause. For now, we suggest that this transient disease is the consequence of choriocapillaris hypoperfusion, but further studies are required to elucidate this hypothesis.

[Role of OCT-angiography in the management of sickle cell retinopathy]

INTRODUCTION

Sickle cell retinopathy is the main ophthalmologic complication of sickle cell syndrome. Optical coherence tomography (OCT) and optical coherence tomography-angiography (OCT-A) permit demonstration of central retinal involvement. The goal of this study is to determine whether central retinal involvement is predictive of peripheral retinal ischemia.

MATERIALS AND METHODS

We carried out a retrospective study of 31 patients with sickle cell disease who underwent a complete ophthalmologic examination. We focused on capillary density of the superficial and deep plexuses and the central avascular surface by OCT-A, and retinal layer thickness by OCT. All of the findings obtained by OCT-A and OCT were classified according to the Goldberg stages on fluorescein angiography.

RESULTS

A thinning of the mean and temporal deep plexus capillary layer as well as a loss of the temporal density of the superficial plexus capillaries are significantly higher in the case of proliferative sickle cell retinopathy (P=<0.05). A significant negative correlation is observed between the mean and temporal density of the superficial (R=-0.31; P=0.02 and R=-0.43; P=0.0009) and deep plexus capillaries (R=-0.39; P=0.003 et R=-0.43; P=0.0009) and the Goldberg stage in fluorescein angiography.

CONCLUSION

The study of the temporal capillary densities of the superficial and deep plexuses on OCT angiography may prove to be a useful tool for the ophthalmologist in order to diagnose patients at risk for proliferative sickle cell retinopathy.

[Update from France Macula Federation: Diagnosis of wet AMD]

PURPOSE

To update the recommendations of the France Macula Federation for the diagnosis of wet age-related macular degeneration (AMD).

METHODS

Analysis of literature and expert opinion.

RESULTS

The FMF recommends diagnosing wet AMD by combining the results of fundus examination (or color or monochromatic fundus photographs), optical coherence tomography (OCT) showing exudative signs, and morphological visualization of the neovascular membrane, which may be obtained non-invasively (OCT-angiography) or invasively (fluorescein and/or indocyanine green angiography). Under optimal conditions in which all these tools are available, the FMF recommends using non-invasive methods as first-line tools and resorting to dye angiography if diagnostic doubt remains.

CONCLUSION

As observed in other fields of medical imaging, non-invasive methods are preferred to invasive methods for the diagnosis of wet AMD, while the latter are reserved for more difficult cases.

[Contribution of multimodal imaging in the various stages of Stargardt disease]

PURPOSE

To describe the contribution of multimodal imaging in the various stages of Stargardt disease (STGD).

PATIENTS AND METHODS

We retrospectively reviewed 46 eyes of 23 STGD patients with identified ABCA4 mutations. All patients underwent a complete ophthalmic examination, spectral-domain optical coherence tomography (SD-OCT), fundus autofluorescence (FAF), fluorescein angiography (FA) and Indocyanine green angiography (ICGA).

RESULTS

The mean age of patients was 25.5 years (range 8-56). Fundus examination was normal in 2 patients (subclinical stage), where SD-OCT showed localized retrofoveolar retinal pigment epithelium (RPE) thickening. FAF was normal in 1 eye and showed mild heterogeneous hyper-FAF in 3 eyes. Twelve eyes had mild salt and pepper changes in the macula (early stage) with diffuse retinal atrophy on SD-OCT and mixed hyper and hypoautofluorescence on FAF. Nine patients showed central atrophy with white-yellow flecks distributed in the posterior pole and mid-periphery. This phenotype showed total foveal atrophy on SD-OCT and normal peripapillary area on FAF. Twelve eyes had a large demarcated area of RPE atrophy, pigment clumping and migration extending to the peripheral retina associated with peripapillary atrophy. These eyes showed diffuse retinochoroidal atrophy on OCT with diffuse alterations reaching the peripapillary area on FAF. On FA, it was difficult to analyze the choroidal silence sign in patients with advanced stages of the disease. A hyperfluorescent window defect pattern was also found in patients with white-yellow flecks and did not correspond exactly to them, or to the areas of peripheral autofluorescent lesions. ICGA showed hypocyanescent areas seen at intermediate and late phases with multiple cyanescent points adjacent to them. On ICGA, hypocyanescent areas were more extensive than lesions observed on FAF.

CONCLUSIONS

Multimodal imaging is helpful for the diagnosis of early stages of STGD disease and to better understand its pathophysiology. FAF and mostly SD-OCT have supplanted FA in the early, especially subclinical, stages. Over all, ICGA shows more extensive damage, making this tool useful for better understanding STGD and suggesting possible direct damage to the choriocapillaris associated with RPE lesions. In advanced stages, only DNA testing can confirm the diagnosis of STGD.

[Choroidal neovascularization complicating Best's vitelliform macular dystrophy in a child]

INTRODUCTION

Best's disease is a progressive macular dystrophy, beginning either in childhood or adolescence.

CASE STUDY

We report a rare case of choroidal neovascularization complicating vitelliform dystrophy in a child of 8 years with bilateral progressive loss of visual acuity. The ophthalmoscopic examination showed vitelliform lesions in both foveas. Fluorescein angiography confirmed a subretinal neovascular membrane in the left eye. Additional testing also confirmed the diagnosis of Best's disease associated with choroidal neovascularization.

DISCUSSION

Best's vitelliform macular dystrophy is often asymptomatic because visual acuity tends to remain stable for a long time. A sudden loss of vision suggests the occurrence of complications, such as choroidal neovascularization.

[Acute Retinal Pigment Epitheliitis: spectral-domain optical coherence tomography findings]

PURPOSE

Through a case presentation of Acute Retinal Pigment Epitheliitis (ARPE) we highlight the role of spectral-domain optical coherence tomography (SD-OCT) in the management of this rare entity.

MATERIALS AND METHODS

A 29-year-old woman presented for reduced visual acuity in the right eye occurring one week after a viral episode. Fundus examination showed zones of macular hyperpigmentation surrounded by yellowish hypopigmented haloes. Fluorescein angiography noted early hyperfluorescence of the hypopigmented lesions. ICG angiography revealed central hyperfluorescence surrounded by a hypofluorescent halo. SD-OCT showed a linear disruption between the photoreceptor inner/outer segments (IS/OS) and an accumulation of material in the photoreceptor outer segments and retinal pigment epithelium (RPE). Spontaneous normalization of visual acuity was noted after 10 weeks. SD-OCT revealed restored and continuous inner segment and outer segment layers and some persistent deposits in the photoreceptor layer.

RESULTS

SD-OCT findings suggest that the initial lesion in ARPE is located at the junction between the photoreceptor outer segments and the apical side of the RPE cells. It would correspond to an accumulation of photoreceptor outer segment debris secondary to RPE dysfunction, which can occur as a post-viral reaction.

CONCLUSION

SD-OCT provides very specific information about the topography of retinal lesions during ARPE, allowing a better understanding of its pathogenesis.