Our purpose is to summarize immunological diseases of the cornea, including their symptoms, diagnostics and potential treatment methods. In such cases, the corneal disease is a symptom of the systemic immunological disease, therefore, in order perform the necessary examinations and to adjust the appropriate treatment, collaboration with an immunologist is imprescendible. However, in some cases consultation with allergologist, rheumatologists and hematologist is also necessary.

Eye drops derived from human serum and plasma can be used effectively to treat a growing spectrum of ocular surface disorders. Blood-based topical therapies can be used effectively and safely in cases of dry eye disease, persistent epithelial defects, neurotropic keratitis, chemical, thermal or irradiation damage to the ocular surface, in addition to conventional conservative treatment or in cases refractory to applied treatment. The process of preparation and storage of blood-derived products is currently not standardised, which may be an obstacle to their wider use. In this review, we summarise the available literature and therapeutic results on the most commonly used blood-derived eye drop preparations.

The amniotic membrane (AM) has a long history of therapeutic use in the treatment of various ocular surface diseases. AM which contains pluripotent cells, highly organised collagen, antifibrotic and anti-inflammatory cytokines, immunomodulators, growth factors and matrix proteins, has outstanding tissue regeneration promoting properties and therefore the indication spectrum and the way of use of AM in ophthalmology is continuously expanding. The present review provides an overview of the anatomy of AM, the technical background of its use, different options for AM preservation, surgical techniques for AM transplantation (AMT) and indications for AM use in ophthalmology.

Aim: A varying degree of anterior stromal haze can often be observed on the treated corneas after corneal cross-linking (CXL) therapy. The amount and exact location of the corneal haze can be determined objectively with the Pentacam HR densitometry software. In our study, we aimed to study the changes in corneal densitometric values after CXL treatment.
Methods: The 49 eyes of 49 keratoconus patients who underwent cross-linking treatment were examined with the Pentacam HR Scheimpflug device before and 1, 3, 6, and 12 months after CXL surgery. Densitometric grayscale units (GSU) were evaluated in the anterior 120 µm, central and posterior 60 µm layers, and in 4 concentric rings of the cornea.
Results: A statistically significant difference was observed between the pre- and postoperative densitometric values in the anterior, central and total layers of the cornea in the 0–2 and 2–6 mm concentric zones at all visits (p <0.05). In the 6–10 mm zone, a significant difference was found in the first and third months (p <0.05). The measured values were the highest in the first and third postoperative months and then showed a decreasing tendency.
Conclusion: Using the densitometry software, the structural changes caused by the CXL treatment can be detected in the central parts of the cornea even one year after the surgery.

Purpose: To present corneal hydrops and the variety of its surgical approaches with a case report.
Case report: A young male patient came to our outpatient care with sudden vision loss of the right eye. Corneal hydrops was confirmed. There were no signs of keratoconus or other ectatic disease in the left eye. An intracameral 20% SF6 gas filling, combined with compression sutures, was performed on the affected eye. Corneal edema decreased from 1479 µm to 991 µm at postoperative day 7, 670 µm at postoperative month 1, 505 µm at postoperative month 6, and 530 µm at the 2-years follow-up. Visual acuity improved from preoperative hand movement to 0.2 at the 6th month and 0.3 at the 2-year follow-up. The cornea became clear, and only a minimal linear scar remained visible
Conclusion: Various surgical interventions have been developed over time to treat corneal hydrops. In accordance with the literature, intracameral gas filling and compression sutures proved to be an effective treatment method with quick improvement, which reduced the intrastromal edema on the first postoperative day. Thus, we managed to prevent extensive scarring and neovascularization of the cornea.

Introduction: Carotid artery stenosis (CAS) is among the leading causes of mortality and permanent disabilities in the Western world. CAS is a consequence of systemic atherosclerotic disease affecting the majority of the aging population. Optical coherence tomography angiography (OCTA) is a novel imaging technique for visualizing retinal blood flow. It is a non-invasive and fast method for qualitative and quantitative assessment of the microcirculation. Cerebral and retinal circulation share similar anatomy, physiology and embryology, thus retinal microvasculature provides a unique opportunity to study pathogenesis of cerebral small vessel disease in vivo.
Methods: A total of 112 eyes of 56 patients with significant carotid stenosis and 90 eyes of 45 healthy control subjects were included in the study. We obtained three consecutive 3x3 mm scans of the macular area and evaluated the vessel density.
Results: Supporting the results of our previous studies, we found that image quality influences the measured data, significantly. Furthermore, we described that the density of the superficial retinal vascular network in the carotid stenosis group was significantly lower compared to the control group.
Conclusion: Our results confirm that the presence of significant carotid stenosis correlates with changes in the microcirculation. OCTA might help in the assessment of cerebral circulation in patients with CAS due to its ability to detect subtle changes in retinal microcirculation.

Purpose: To report a case of COVID-19-associated papillitis.
Methods: We present the case of a 44-year-old man who experienced right and then left central progressive visual loss during the course of symptomatic coronavirus (COVID-19) disease. His complaints were confirmed as bilateral swollen optic nerve heads.
Results: Following hospital admission, urgent neurological and internal medicine consultation, cranial imaging, and laboratory investigations were performed, followed by systemic general intravenous Solu-Medrol administration (from 80 mg) in gradually decreasing doses with potassium supplementation, gastric protection, and prophylactic anticoagulation. After 4 months of treatment, the patient's visual acuity improved from 0.2 to 0.9-1.0 in the right eye and remained unchanged at 1.0 in the left eye. The bilateral optic nerve head swelling was resolved. In the 2 months after discontinuation of general therapy, his vision deteriorated to 0.3 in the right eye and remained at 1.0 in the left, the optic nerve heads became pale, and the nerve fibre layer thickness decreased in both eyes.
Conclusion: Based on the literature and the clinical picture, we consider the seen COVID-19-associated papillopathy to have been a bilateral anterior optic neuritis (papillitis) most likely. Our case report draws attention to a possible ophthalmological complication of coronavirus disease.