Purpose. To assess the ability of optical coherence tomography-angiography (OCT-A) to show and analyze retinal vascular patterns and the choroidal neovascularization (CNV) in retinal vascular diseases.Methods. Seven eyes of seven consecutive patients with retinal vascular diseases were examined. Two healthy subjects served as controls. All eyes were scanned with the SD-OCT XR Avanti (Optovue Inc, Fremont CA, USA). Split spectrum amplitude decorrelation angiography algorithm was used to identify the blood flow within the tissue. Fluorescein angiography (FA) and indocyanine green angiography (ICGA) with Spectralis HRA + OCT (Heidelberg Engineering GmbH) were performed.Results. In healthy subjects OCT-A visualized major macular vessels and detailed capillary networks around the foveal avascular zone. Patients were affected with myopic CNV (2 eyes), age-related macular degeneration related (2), branch retinal vein occlusion (BRVO) (2), and branch retinal artery occlusion (BRAO) (1). OCT-A images provided distinct vascular patterns, distinguishing perfused and nonperfused areas in BRVO and BRAO and recognizing the presence, location, and size of CNV.Conclusions. OCT-A provides detailed images of retinal vascular plexuses and quantitative data of pathologic structures. Further studies are warranted to define the role of OCT-A in the assessment of retinovascular diseases, with respect to conventional FA and ICG-A.

Metabolomics based on mass spectrometry represents an innovative approach to characterize multifactorial diseases, such as multiple sclerosis (MuS). To date, the most important biomarker source for MuS diagnosis is the cerebrospinal fluid. However, an important goal for research is to identify new molecules in more easily accessible biological fluids. A very interesting biofluid in MuS is represented by tears, considered as an intermediate fluid between the cerebrospinal fluid and serum. In this work, we developed a merged strategy for the analysis of lipids containing choline by Liquid Chromatography coupled to Tandem Mass Spectrometry (LC-MS/MS), as well as for the targeted analysis of free carnitine, acylcarnitines and aminoacids by direct infusion mass spectrometry. Samples for both metabolomics and lipidomics approaches were obtained in a single extraction procedure from tears of patients affected by MuS and healthy controls. Tear lipidomics showed 30 phospholipids significantly modulated and, notably, many sphingomyelins resulted lower in MuS. Moreover, the metabolomics approach carried out both on tears and serum highlighted the diagnostic potential of specific aminoacids and acylcarnitines. In conclusion, the metabolic profiling of tears appears to reflect the pathological conditions of the central nervous system, suggesting that the molecular repository of tears can be considered as a source of potential biomarkers for MuS.

Primary open-angle glaucoma (POAG) represents the leading cause of irreversible blindness worldwide and is a multifactorial, chronic neurodegenerative disease characterized by retinal ganglion cell and visual field loss. There are many factors that are associated with the risk of developing POAG, with increased intraocular pressure being one of the most prevalent. Due to the asymptomatic nature of the disease, the diagnosis of POAG often occurs too late, which necessitates development of new effective screening strategies for early diagnosis of the disease. However, this task still remains unfulfilled. In order to provide further insights into the pathophysiology of POAG, we applied a targeted metabolomics strategy based on a high-throughput screening method for the determination of tear amino acids, free carnitine, acylcarnitines, succinylacetone, nucleosides, and lysophospholipids in naïve to therapy glaucomatous patients and normal controls. Also, we conducted proteomic analyses of the whole lacrimal fluid and purified extracellular vesicles obtained from POAG patients and healthy subjects. This multi-omics approach allowed us to conclude that POAG patients had lower levels of certain tear amino acids and lysophospholipids compared with controls. These targeted analyses also highlighted the low amount of acetylcarnitine (C2) in POAG patient which correlated well with proteomics data. Moreover, POAG tear proteins seemed to derive from extracellular vesicles, which carried a specific pro-inflammatory protein cargo.

Aim To investigate, using laser scanning confocal microscopy (LSCM), the morphological changes of meibomian glands (MGs) in patients with glaucoma. Methods A total of 80 patients who were glaucomatous were enrolled, and 20 healthy subjects were used as controls. After completing an Ocular Surface Disease Index (OSDI) questionnaire, all subjects underwent tear film break-up time (BUT), fluorescein staining, Schirmer test I (STI) and LSCM examination of the MGs. The main outcome measures were: eyelid margin epithelial cell density, mean acinar density (MAD) and area (MAA), glandular orifice area, secretion reflectivity and inhomogeneous appearance of interstice and acinar wall. Results According to the number of anti-glaucoma medications they were taking, patients were divided into three groups: group 1 (30 eyes), one drug; group 2 (23 eyes), two drugs; group 3 (27 eyes), three or more drugs. LSCM showed lower MAD and MAA, greater secretion reflectivity and glandular orifice area in groups 2 and 3 than in controls (p<0.05). The inhomogeneity of the interstice and acinar wall was significantly greater in all groups compared to controls (p<0.05). Preserved prostaglandin analogues (PGAs) induced more pronounced modifications of all parameters than preservative free (PF)-PGAs (p<0.05). No significant differences were found between preserved and PF-β-blockers. Significant relations were found among MAD, MAA, secretion reflectivity and OSDI score, BUT and ST (p<0.05) and between secretion reflectivity and orifice area (p<0.001). Conclusions In vivo LSCM is an effective tool in revealing morphological changes of MGs induced by anti-glaucoma medications. Given the key role in the ocular surface health, the evaluation of MG status in patients who are glaucomatous is worthwhile.