Correlation of retinal alterations with vascular structure of macular neovascularisation in swept-source optical coherence tomography angiography in age-related macular degeneration

Purpose The aim of this study was to find out whether the vascular architecture of untreated macular neovascularisations (MNV) in neovascular age-related macular degeneration (nAMD) as visualised with optic coherence tomography angiography (OCTA) is associated with functional and known morphological alterations of the retina in optic coherence tomography (SD-OCT). Methods The study design was retrospective with consecutive patient inclusion. In 107 patients with newly diagnosed nAMD, MNV were detected by means of OCTA and automated quantitative vascular analysis was performed. The MNV characteristics measured were area, flow density, total vascular length (sumL), density of vascular nodes (numN), fractal dimension (FD) and average vascular width (avgW). These parameters were assessed for associations with vision (BCVA), central retinal thickness (CRT), fluid distribution, the elevation of any pigment epithelial detachment (PED), the occurrence of subretinal haemorrhage and atrophy. Results BCVA was significantly worse with greater MNV area and sumL. Fluid distribution differed significantly in relation to area (p < 0.005), sumL (p < 0.005) and FD (p = 0.001). Greater PED height was significantly associated with higher numN (p < 0.05) and lower avgW (p < 0.05). Atrophy was present significantly more often in MNV with larger area (p < 0.05), higher sumL (p < 0.05) and higher flow density (p = 0.002). None of the MNV parameters had a significant association with CRT or the occurrence of haemorrhage. Conclusion OCTA is not restricted to evaluation of secondary changes but offers the opportunity to analyse the vascular structure of MNV in detail. Differences in vascular morphology are associated with certain secondary changes in retinal morphology. There are thus grounds for optimism that further research may identify and classify OCTA-based markers to permit more individualised treatment of nAMD.

Retinal vessel tortuosity as a prognostic marker for disease severity in Fabry disease

Purpose The aim of this case control study was to evaluate the prognostic value of automatically quantified retinal vessel tortuosity from fundus images and vessel density from OCT-A in Fabry disease and to evaluate the correlation of these with systemic disease parameters. Methods Automatically quantified perimacular retinal vessel tortuosity (MONA REVA software), acquired by fundus imaging, and perifoveal retinal vessel density, acquired by optic coherence tomography angiography (OCT-A) were compared between 26 FD patients and 26 controls. Gender and FD phenotype were analyzed to the obtained retinovascular data and correlated to the Mainz severity score index (MSSI) and plasma lyso-Gb3. Results Automatically quantified retinal vessel tortuosity indices of FD patients were significantly lower, reflecting an increased vessel tortuosity, compared to controls (p = 0.008). Males with a classical phenotype showed significantly lower retinal vessel tortuosity indices compared to males with an oligosymptomatic phenotype and females with a classical or oligosymptomatic phenotype (p < 0.001). The retinal vessel tortuosity index correlated significantly with systemic disease severity parameters [global MSSI (r = − 0.5; p < 0.01), cardiovascular MSSI (r = − 0.5; p < 0.01), lyso-Gb3 (r = − 0.6; p < 0.01)]. Conclusion We advocate fundus imaging based automatically quantified retinal vessel tortuosity index over OCT-A imaging as it is a quick, non-invasive, easily assessable, objective and reproducible marker.

Multimodal Imaging, OCT En Face, and OCT Angiography of an Anomalous Retinal Artery: Case Report and Review of the Literature

The purpose is to study for the first time the vascular plexuses and the retinal nerve fiber layer and raphe of a patient with a very uncommon anatomical variation: an anomalous retinal artery supplying the whole macula. We used multimodal imaging, en face spectral-domain optic coherence tomography, and spectral-domain optic coherence tomography angiography. One patient presented in his left eye a very unusual anatomical variation of macular vascularization. A retinal artery deriving from the inferior temporal retinal artery irrigated the whole macula. The formation of the papillomacular bundle and the temporal raphe nerve fiber layer has been attributed to the earlier development of the central retina and to the existence of 2 distinct watershed zones. However, there are very uncommon anatomical variations of the retinal vasculature in which large retinal vessels cross the raphe and could influence the morphology and structure of the nerve fiber layer of the posterior pole. We review the literature on the subject and document for the first time an anomalous artery that irrigates the whole macula, normal thickness and morphology of the nerve fiber layer, and the temporal raphe.

Ocular ischemic manifestations in fibromuscular dysplasia

Purpose: To report visual, clinical and radiological outcomes of three patients with fibromuscular dysplasia (FMD) that presented different ocular ischemic events, supported by different multimodal imaging. Methods: A retrospective study including patients who attended a tertiary referral hospital from July 2016 to June 2019 referring acute visual loss and later diagnosed of FMD. Ophthalmological examination included best corrected visual acuity (BCVA), biomicroscopy, fundoscopy, fluorescein angiography (FA), and macular and retinal nerve fiber layer spectral domain optic coherence tomography (SD-OCT). Patients were admitted by the Neurology service, completing the study with blood and cerebrospinal fluid (CSF) test, serology and cultures, cerebral magnetic resonance angiography (angioMRI), and arteriography. Results: Three patients were included; one male and second females. All referred unilateral acute visual loss, with BCVA of counting fingers or hand-motion. Relative afferent pupilar defect was present in all patients. Two patients associated neurological focal signs and one had chronic hypertension. Fundoscopy revealed hemorrhages and exudates in all patients, and the typical sign of “string-of-beads” in one. FA showed dye filling delay and macular and peripheral hypofluorescence. SD-OCT revealed acute and chronic retinal ischemic signs. Blood and CSF tests, serologies and cultures resulted negative. All presented cerebral vascular involvement, objectified in the cerebral angioMRI or arteriography. Conclusions: FMD should be considered in cases with unilateral sudden visual loss associated to neurological focal deficits in young patients. The typical “string-of-beads” image is rare in small arteries such as the retinal vasculature. When suspected, a complete ophthalmological examination and cerebral vascular imaging is essential to confirm the diagnosis.

Efficacy of Low-Dose Rituximab on Neuromyelitis Optica-Associated Optic Neuritis

Purpose: To prospectively investigate the efficacy and tolerance of low-dose rituximab (RTX) for the treatment of neuromyelitis optica-associated optic neuritis (NMO-ON).Methods: Optic Neuritis patients with seropositive aquaporin 4-antibody (AQP4-Ab) were diagnosed with NMO-ON and recruited for treatment with low-dose RTX (100 mg * 4 infusions) and were then followed monthly for a minimum of 3 months. Reinfusion of 100 mg RTX was given when the CD19+ B lymphocyte frequency was elevated to above 1%. The serum AQP4-Ab level was tested by an enzyme-linked immunosorbent assay (ELISA).Results: A total of 43 NMO-ON patients (1 male/42 female, 75 involved eyes) were included in this study. CD19+ B cell clearance in the peripheral blood was induced in 97.7% of patients after induction treatment. A significant decrease in serum AQP4-Ab concentration was observed after induction treatment (P = 0.0123). The maintenance time of B cell clearance was 5.2 ± 2.25 months. The relapse-free rate was 92.3% in patients followed-up for over 12 months, and patients with non-organ-specific autoimmune antibodies tended to relapse within 6 months. A total of 96.2% of patients had stable or improved vision, and a decrease in the average expanded disability status scale (EDSS) score was found. Structural alterations revealed by optic coherence tomography were observed in both ON and unaffected eyes. The rates of infusion-related reactions and long-term adverse events (AEs) were 18.6 and 23.1%, respectively. No severe AEs was observed.Conclusions: Low-dose rituximab is efficient and well-tolerated in treating NMO-ON.

Decreased Central and Limbal Epithelium Thickness After Corneal Crosslinking Evaluated by Anterior Segment Optic Coherence Tomography

Aim: To Investigate the central cornea, limbal epithelium thickness and stroma thickness after corneal cross-linking by Anterior Segment Optical Coherence Tomography (AS-OCT) and Scheimpflug topography.Methods: Fifteen keratoconus patients treated with cross-linking(CXL) and fifteen untreated keratoconus patients was included to the study. Corneal central, limbal epithelial, stromal and total thickness with was analyzed by using Anterior Segment Optical Coherence Topography (AS-OCT) and keratometric values ​​were analyzed by Scheimpflug topography.Results: There was a statisticallly significant difference between treated and untreated keratoconus patients according to limbal epithelial thickness (LET). Limbal epithelial thickness was 30.7 ± 5.5µm in the treated keratoconus patients and 45.6 ± 11.5µm in the untreated patients (p = 0.04). Central corneal epithelial thickness (CCET) was 38.27±3.5 in the treated group and 60.8 ± 10.9µm in the untreated group. There was a statistically signifficant difference the between two groups (p=0.01). The posterior astigmatism value was 0.7 ± 0.3D in the treated group and 0.9 ± 0.5D in untreated group by Scheimpflug topography (p=0.03).Conclusion: Our study have shown that the central corneal epithelium and limbal epithelium were significantly thinned as a result of corneal cross-linking. Corneal posterior astigmatism value decreased among the keratometric values. Epithelial thickness and limbal thickness alterations detected with Ant-OCT could be useful for monitorizing the keratoconus patients treated with crosslinking and could show the effectivity of the treatment.