Repeatability of swept-source optical coherence tomography angiography automated macular vessel density

INTRODUCTION

Optical Coherence Tomography Angiography Ratio Analysis (OCTARA) is capable of visualizing inner and outer retinal vascular plexuses, choriocapillaris, and larger choroidal vasculature in vivo without contrast injection. The aim of this study was to assess the intrasession repeatability of automated vessel density measurements using Triton Swept-Source Optical Coherence Tomography Angiography (OCTA) innovative algorithm OCTARA in retinal and choroidal vasculature.

METHODS

To study population between 65-90 years old with no eye diseases. For each subject measurements were performed four times. The intraclass correlation coefficient and the coefficient of variation were calculated to analyze repeatability of the OCTARA automatically generated vessel density measurements.

RESULTS

A total of 35 eyes were included in the study. The intraclass correlation coefficient of the global vessel density in the superficial capillary plexus and the deep capillary plexus were 0.963 and 0.975, respectively, and the coefficient of variation were 5.4% and 4.4%, respectively. The intraclass correlation coefficient of the rest of the global measurements was indicative of good reliability with the exception of the deep choroid layer with an intraclass correlation coefficient of 0.6 indicative of moderate reliability.

CONCLUSIONS

Our results proved excellent repeatability of automated vessel density measurements in the superficial and deep capillary plexus layers in our cohort using a OCTARA algorithm indicating that it may be a reliable diagnostic tool. It also showed good reliability in choriocapillary and mid choroid layer. These findings may be of value in assessing the significance of differences in capillary density measurements over time and across different settings.

New insights in the pathogenic mechanism of multiple sclerosis: Is Epstein-Barr virus associated with optic nerve involvement?

INTRODUCTION

There are no reports in the literature studying the possible relationship between Epstein-Barr virus (EBV) and optic nerve involvement in multiple sclerosis (MS). The aim of our study was to analyze the association between EBV antibodies titres and optical coherence tomography (OCT) and OCT angiography (OCTA) quantitative parameters.

METHODS

We conducted a retrospective study. The study included 98 eyes of 49 patients with MS. Years of MS duration, relapse count, history of optic neuritis (ON), and immunoglobulin (Ig) G antibodies to the EBV viral capsid antigen (VCA) were recorded from each patient. Also, OCT analysis (including retinal nerve fibre layer (RNFL) thickness and ganglion cell-inner plexiform layer (GCIPL) thickness) and OCTA analysis (including perfusion density (PD) and flux index (FI) of the radial peripapillary capillary plexus) were performed in each participant.

RESULTS

No significant associations were observed between anti-EBV antibody levels and OCT or OCTA parameters (p > 0,05). Correlation analysis between OCT and OCTA measurements showed a significant positive correlation between RNFL thickness and GCIPL thickness with peripapillary PD and FI (p < 0,035). Subgroup analysis revealed a significant diminution of RNFL thickness, GCIPL thickness and peripapillary PD and FI (p < 0,05) in the ON group.

CONCLUSION

We were unable to demonstrate a significant association between anti-EBV VCA IgG antibody titres and OCT or OCTA parameters. Nonetheless, further longitudinal studies are needed to explore the possible association of EBV with optic nerve involvement in MS.

Aneurysmal type 2 neovascularization: A new entity

PURPOSE

To report three cases of aneurysmal type 2 neovascularization (AT2), a novel entity within the pachychoroid disease (PD) spectrum.

METHODS

We conducted an observational retrospective study of three patients with subretinal polyps treated with intravitreal aflibercept. We reviewed clinical and imaging data of the three patients. Best corrected visual acuity (BCVA), central macular thickness (CMT), choroidal subfoveal thickness, choroidal thickness under the polyps and the presence of a dry macula were assessed at baseline and throughout the follow-up.

RESULTS

All of the patients showed granular hypoautofluorescence on fundus autofluorescence. Indocyanine green angiography revealed prominent hyperfluorescent branching vascular networks ending in multiple aneurysmal dilatations. Optical coherence tomography (OCT) demonstrated that the aneurysmal lesions were localized in the subretinal space. Additionally, OCT showed retinal pigment epithelial microtears, the double-layer sign and pachyvessels. En face OCT-A perfectly defined prominent telangiectatic branching vascular networks in all the patients, but only revealed polyps in two out of the three patients. Cross-sectional OCT-A demonstrated polyps as patchy circular hypoflow signals in each case. After the intravitreal treatment, BCVA remained unimproved in all of the patients, despite decreased CMT and achievement of a dry macula, as a result of the development of subretinal fibrosis.

CONCLUSION

In summary, we describe a new entity within the spectrum of PD, which we have termed AT2. This novel disease is characterized by the presence of aneurysmal dilatations in the subretinal space, along with the typical features of PD, such as choroidal vascular hyperpermeability, thickening of the choroid and pachyvessels.

Optical coherence tomography angiography analysis in patients with intracranial hypertension

INTRODUCTION

Evidence on peripapillary microvasculature in intracranial hypertension (IH) after the regression of papilledema is still scarce. The aim of this preliminary study was to determine the association between structural changes in the optic nerve and the retina and peripapillary microvasculature in patients with IIH.

METHODS

We conducted a retrospective study. The study included 39 eyes of 21 patients with IIH. Treatment for IIH and history of obesity were registered from each patient. Moreover, OCT analysis including retinal nerve fiber layer (RNFL) thickness and ganglion cell-inner plexiform layer (GCIPL) thickness, and OCTA analysis including perfusion density (PD) and flux index (FI) of the radial peripapillary capillary plexus were performed.

RESULTS

Correlation analysis revealed a high correlation between GCIPL thickness and peripapillary PD and FI (p < 0,05, r > 0,7), whereas the degree of correlation between RNFL thickness and peripapillary microvascular parameters was low (p < 0,05, r < 0,7). Patients with regressed papilledema had significantly lower GCIPL thickness and peripapillary PD than control subjects (p < 0,05).

CONCLUSION

Peripapillary microvascular measurements are highly correlated with GCIPL thickness in patients with IIH. Moreover, GCIPL thickness and peripapillary PD are significantly inferior in patients with regressed papilledema compared to control group. Thus, we suggested that peripapillary microvascular parameters may be an early indicator of optic nerve atrophy in patients with IIH.

Quantitative Assessment of Retinal and Choroidal Microvasculature in Asymptomatic Patients with Carotid Artery Stenosis

SIGNIFICANCE

Carotid disease contributes to 15 to 20% of all ischemic strokes, one of the leading causes of permanent disabilities and mortality globally. With its growing prevalence and the inflicted disability rates, screening for anomalies that precede the onset of its serious complications is of crucial global significance.

PURPOSE

This study aimed to assess the relationship between retinal and choroidal perfusion changes with the degree of stenosis using quantitative swept-source optical coherence tomography angiography in patients with internal carotid artery stenosis.

METHODS

A retrospective cohort study was conducted in 72 eyes with carotid stenosis. According to the degree of stenosis, the participants were divided into a healthy group (group 1: 34 eyes), a mild-moderate stenosis group (group 2: 22 eyes), and a severe stenosis group (group 3: 16 eyes). Swept-source optical coherence tomography angiography was performed to scan macular fovea. Capillary density values in the different retinal and choroidal layers were the major measurements for our study.

RESULTS

Mean vessel density in the midchoroid layer was significantly higher in groups 2 and 3 compared with group 1. Deep choroid disclosed significantly superior vascular density values in group 3 compared with groups 2 and 1. Superficial and deep capillary plexus showed decreased vascular density values when comparing group 3 with groups 1 and 2, although they were not significant.

CONCLUSIONS

Our report provides the first evidence that choroidal microvascular changes were correlated with severity of carotid artery stenosis. Optical coherence tomography angiography can sensitively detect subtle, early changes in the ocular blood in carotid disease representing a useful, noninvasive, and objective approach to the retinal microvasculature.

Case Report: Multimodal Imaging Features of an ABCA4 Cone Dystrophy

SIGNIFICANCE

Cone dystrophies and cone-rod dystrophies are a group of rare inherited pathologies characterized by degeneration of cone photoreceptors and subsequent rod involvement. The identification of causative genes is essential for diagnosis, and advanced imaging is acquiring great value in the characterization of the different phenotypic expressions.

PURPOSE

We describe genotype-phenotype associations of an autosomal recessive ABCA4-associated cone dystrophy using multimodal imaging.

CASE REPORT

A 34-year-old woman presented with progressive visual acuity decay. Visual acuity was 20/32 for her right eye and 20/25 for her left eye. A central scotoma was detected on a 10-2 Humphrey visual field in both eyes. Funduscopy revealed perifoveal retinal pigment epithelial changes, and fundus autofluorescence using blue excitation light showed decreased autofluorescence in the central fovea of both eyes with surrounding annular ring of increased autofluorescence in the perifoveal zone; green excitation light fundus autofluorescence was more accurate in the characterization of the size, perimeter, and circularity of central hypofluorescent lesions. Optical coherence tomography revealed an incomplete focal cavitation in both foveas, and optical coherence tomography angiography images showed a reduction in the superficial and deep capillary plexus density, an increased foveal avascular area, and subtle voids in choriocapillaris blood flow. Electroretinography was consistent with cone dystrophy, and molecular testing revealed the alteration of the ABCA4 gene.

CONCLUSIONS

The identification of an incomplete focal cavitation could alert the clinician to consider early ABCA4 central cone dystrophy. The patient in this case also exhibited reduced vessel density in the foveal area. Both of these characteristics could be important features related to the underlying genetic mutation.

Case Report: Ipilimumab-induced Multisystem Autoimmune-like Toxicities Suggestive of Vogt-Koyanagi-Harada-like Syndrome

SIGNIFICANCE

The emergence of new cancer therapies has dramatically improved outcomes in metastatic melanoma. Immune checkpoint inhibitors have been the most effective treatment. Although, as a direct consequence of the immune dysregulation induced by them, adverse effects termed immune-related adverse events are observed in more than 60% of the patients.

PURPOSE

We describe the clinical presentation of Vogt-Koyanagi-Harada-like syndrome in a patient with concomitant systemic melanoma treatment with ipilimumab, a cytotoxic T lymphocyte-associated antigen 4 blocker.

METHODS

This study aimed to report a case of ipilimumab-induced vitritis, papillitis, and skin and auditory signs suggestive of Vogt-Koyanagi-Harada-like syndrome.

CASE REPORT

A 64-year-old woman with metastatic melanoma presented with bilateral blurred vision and hearing loss upon completion of three cycles of treatment with ipilimumab. Ophthalmologic examination revealed a bilateral granulomatous uveitis with intense vitritis and papillitis. The result of optical coherence tomography was normal, and fluorescein angiography confirmed the bilateral papillary edema. Ipilimumab was withdrawn, and treatment with oral and systemic steroids led to a rapid improvement in the ophthalmologic and auditory manifestations. Three months after initial presentation, the patient developed vitiligo and poliosis.

CONCLUSIONS

Vogt-Koyanagi-Harada-like syndrome can develop in the process of immunological deregulation by ipilimumab in the treatment of metastatic melanoma and can correlate temporally with the efficacy of the drug in tumor regression. These observations may help elucidate the underlying mechanism of Vogt-Koyanagi-Harada syndrome as well as the relation between tumor-associated tolerance and autoimmunity.

A case of bilateral unusual retinal hemorrhages in a COVID-19 patient

PURPOSE

There have been anecdotal reports of ocular manifestations in the Coronavirus Disease 2019 (COVID-19). As the pandemic is spreading and the whole picture is yet unknown, ophthalmologists should be aware of unusual ocular presentations of COVID-19 since they could precede the development of severe respiratory distress.

METHODS

We report here the first case of a patient with bilateral unusual dot-blot retinal hemorrhages and retinal venous dilation who presented shortly thereafter a PCR-proven COVID-19.

CASE REPORT

A 59-year-old woman presented with a 7 days history of blurred vision in both eyes. Fundus examination revealed bilateral venous stasis and dot and blot intra-retinal hemorrhages preceding the diagnosis of COVID-19 in a patient with mild respiratory symptoms that progressed within a few days to a severe respiratory distress. After 1 month of the COVID-19 treatment, fundus examination improved and fluorescein angiography demonstrated no diabetic retinopathy signs, no retinal vasculitis and no significant delay in arterial or venous filling.

CONCLUSION

Intraretinal hemorrhages similar to those found in the retinopathy associated to blood dyscrasias could be an association with SARS-CoV-2 in the context of a coagulopathy induced by the infection.

Rituximab in the treatment of Susac’s syndrome: Report of a case

Significance

Susac’s syndrome is a rare retinocochleocerebral immune-mediated endotheliopathy and clinically manifests as a pathognomonic triad of encephalopathy, hearing loss, and branch retinal artery occlusion. This triad is rarely present at symptom onset, thus, it is often initially misdiagnosed. To date, Susac’s syndrome has persisted as an elusive entity and there are numerous treatment regimens proposed with varying effectiveness mainly based on case series.

Purpose

To report our 12-month follow-up experience in the treatment of Susac’s syndrome with rituximab.

Case report

A 25-year-old female presenting with headache, paresthesias, tinnitus, peripheral vertigo, and a branch retinal artery occlusion. The patient had a personal history of anxiety-depressive disorder. After discarding other infectious/autoimmune conditions and magnetic resonance imaging suggestive findings of Susac’s syndrome, we observed a prompt response to the combination of intravenous immunoglobulin, corticosteroids, and rituximab.

Conclusion

A standard treatment paradigm is lacking in Susac’s syndrome as randomized controlled trials do not exist. There are no definitive scores to predict its outcome, and early diagnosis is important as the organs involved can easily become irreversibly damaged. Thus, patients with Susac’s syndrome must be treated promptly and aggressively. Our report highlights the possibility of positive long-term prognosis with an early use of rituximab. However, a systematic therapeutic approach on the basis of controlled trials is mandatory to develop a consensus.