Ηλεκτροφυσιολογική μελέτη οφθαλμών σε ασθενείς με βήτα μεσογειακή αναιμία

Εισαγωγή Η βήτα μεσογειακή αναιμία είναι μια κληρονομική νόσος του αίματος, η οποία χαρακτηρίζεται από απουσία ή μειωμένη σύνθεση των β αλυσίδων της αιμοσφαιρίνης στα ερυθρά αιμοσφαίρια. Οφθαλμικές εκδηλώσεις της νόσου περιλαμβάνουν η οπτική νευροπάθεια και η αμφιβληστροειδοπάθεια, οι οποίες θεωρούνται αποτέλεσμα είτε της συσσώρευσης σιδήρου στον αμφιβληστροειδή λόγω των συχνών μεταγγίσεων είτε της τοξικότητας από τη θεραπεία αποσιδήρωσης. Σκοπός Σκοπός της μελέτης ήταν να εκτιμηθεί ο ρόλος διαφόρων διαγνωστικών εξετάσεων στην ανίχνευση πρώιμων αλλοιώσεων του αμφιβληστροειδή ασθενών με ομόζυγη β-μεσογειακή αναιμία. Μέθοδος Στη μελέτη συμπεριλήφθησαν τριάντα οκτώ ασθενείς με ομόζυγη β-μεσογειακή αναιμία χωρίς συμπτώματα από τους οφθαλμούς, οι οποίοι υποβάλλονταν σε συχνές μεταγγίσεις αίματος και λάμβαναν αγωγή αποσιδήρωσης με δεσφερριοξαμίνη (ομάδα Α, n=13), δεφερασιρόξη (ομάδα Β, n=11) ή συνδυασμό δεσφερριοξαμίνης με δεφεριπρόνη (ομάδα Γ, n=14) και 14 υγιείς μάρτυρες ίδιας ηλικίας και φύλου. Όλοι οι συμμετέχοντες υποβλήθηκαν σε βυθοσκόπηση και μελέτη με ηλεκτροαμφιβληστροειδογράφημα (ΗΑΓ), οπτικά προκλητά δυναμικά ινιακού λοβού (ΔΙΛ), πολυεστιακό ΗΑΓ, αυτοφθορισμό βυθού και οπτική τομογραφία συνοχής (OCT) της ωχράς κηλίδας. Αποτελέσματα Δύο ασθενείς εμφάνισαν διαταραχές του μελάγχρου επιθηλίου στη βυθοσκόπηση. Το σκοτοπικό ΗΑΓ ανέδειξε ελαττωμένο ύψος του κύματος α στις ομάδες Α, Β και Γ (p=0,03, p=0,002 και p=0,002, αντίστοιχα) και ελαττωμένο ύψος του κύματος β στις ομάδες Β και Γ (p=0,002 και p=0,01, αντίστοιχα) σε σύγκριση με την ομάδα ελέγχου. Το φωτοπικό ΗΑΓ έδειξε παράταση του λανθάνοντα χρόνου εμφάνισης του κύματος β στις ομάδες Α και Γ (p=0,03 και p=0,03, αντίστοιχα). Η απάντηση στο μέγιστης απάντησης ΗΑΓ και στα ΔΙΛ δεν διέφερε ανάμεσα στις ομάδες. Το πολυεστιακό ΗΑΓ φανέρωσε μειωμένη αμφιβληστροειδική απάντηση στον κεντρικό δακτύλιο 1 στις ομάδες Α, Β και Γ (p<0,001, p<0,001 και p<0,001, αντίστοιχα) και στον δακτύλιο 2 στην ομάδα Β (p=0,02) και παράταση του χρόνου στον δακτύλιο 5 στις ομάδες Α και Β (p=0,04 και p=0,04, αντίστοιχα). Παθολογικές εικόνες αυτοφθορισμού εμφάνισαν τρεις οφθαλμοί και αλλοιώσεις στην OCT ένας οφθαλμός, ενώ οι μάρτυρες δεν παρουσίασαν καμία διαταραχή (p=0,55 και p=1,00, αντίστοιχα). Συμπέρασμα Το ΗΑΓ και το πολυεστιακό ΗΑΓ είναι πιο ευαίσθητες εξετάσεις από τη βυθοσκόπηση, τα ΔΙΛ, τον αυτοφθορισμό και την OCT ωχράς κηλίδας στην ανίχνευση πρώιμων αλλοιώσεων στον αμφιβληστροειδή ασθενών με ομόζυγη β-μεσογειακή αναιμία.Introduction Beta thalassemia major is an autosomal recessive blood disease characterized by reduced beta globin chain synthesis. Ocular findings include optic neuropathy and retinal abnormalities, which may occur due to either retinal iron accumulation resulting from frequent blood transfusions or retinal toxicity induced by chelation therapy. Purpose The purpose of this study was to assess the role of various diagnostic tests in early detection of retinal changes in β-thalassemia major (β-ΤΜ) patients. Materials & Methods Thirty-eight visually asymptomatic β-ΤΜ patients receiving regular blood transfusions and iron-chelation therapy with deferoxamine (group A, n = 13), deferasirox (group B, n = 11) or deferoxamine with deferiprone (group C, n = 14) and fourteen age- and sex- matched healthy individuals were included in the study. All participants underwent ophthalmoscopy, full-field electroretinography (ERG), visual evoked potentials (VEP), multifocal electroretinography (mfERG), fundus autofluorescence (FAF) imaging and optical coherence tomography (OCT) scans. Results Retinal pigment epithelium changes were present in two β-ΤΜ patients. Scotopic ERG demonstrated decreased a-wave amplitude in groups A, B and C (p = 0,03, p = 0,002 and p = 0,002, respectively) and decreased b-wave amplitude in groups B and C (p = 0,002 and p = 0,01, respectively) compared to controls. Photopic ERG showed delayed b-wave latency in groups A and C (p = 0,03 and p = 0,03, respectively). VEP response did not differ between groups. MfERG showed reduced retinal response density in ring 1 in groups A, B, C (p < 0,001, p < 0,001, p = 0,001, respectively) and ring 2 in group B (p = 0,02) and delayed latency in ring 5 in groups A and B (p = 0,04 and p = 0,04, respectively). Abnormal FAF images appeared in three cases and OCT abnormalities in one case, whereas no changes were observed in controls (p = 0,55 and p = 1,00, respectively). Conclusion Full-field ERG and mfERG are more sensitive tools for detecting early retinal changes in β-TM patients compared with ophthalmoscopy, VEP, FAF imaging and OCT scans

Guanylyl cyclase activation reverses resistive breathing–induced lung injury and inflammation

Inspiratory resistive breathing (RB), encountered in obstructive lung diseases, induces lung injury. The soluble guanylyl cyclase (sGC)/cyclic guanosine monophosphate (cGMP) pathway is down-regulated in chronic and acute animal models of RB, such as asthma, chronic obstructive pulmonary disease, and in endotoxin-induced acute lung injury. Our objectives were to: (1) characterize the effects of increased concurrent inspiratory and expiratory resistance in mice via tracheal banding; and (2) investigate the contribution of the sGC/cGMP pathway in RB-induced lung injury. Anesthetized C57BL/6 mice underwent RB achieved by restricting tracheal surface area to 50% (tracheal banding). RB for 24 hours resulted in increased bronchoalveolar lavage fluid cellularity and protein content, marked leukocyte infiltration in the lungs, and perturbed respiratory mechanics (increased tissue resistance and elasticity, shifted static pressure–volume curve right and downwards, decreased static compliance), consistent with the presence of acute lung injury. RB down-regulated sGC expression in the lung. All manifestations of lung injury caused by RB were exacerbated by the administration of the sGC inhibitor, 1H-[1,2,4]oxodiazolo[4,3-]quinoxalin-l-one, or when RB was performed using sGCα1 knockout mice. Conversely, restoration of sGC signaling by prior administration of the sGC activator BAY 58-2667 (Bayer, Leverkusen, Germany) prevented RB-induced lung injury. Strikingly, direct pharmacological activation of sGC with BAY 58-2667 24 hours after RB reversed, within 6 hours, the established lung injury. These findings raise the possibility that pharmacological targeting of the sGC–cGMP axis could be used to ameliorate lung dysfunction in obstructive lung diseases

Electrophysiological assessment for early detection of retinal dysfunction in patients with beta thalassemia

Beta thalassemia major is an autosomal recessive blood disease characterized by reduced beta globin chain synthesis. Ocular findings include optic neuropathy and retinal abnormalities, which may occur due to either retinal iron accumulation resulting from frequent blood transfusions or retinal toxicity induced by chelation therapy. Purpose: The purpose of this study was to assess the role of various diagnostic tests in early detection of retinal changes in β-thalassemia major (β-ΤΜ) patients. Materials & Methods: Thirty-eight visually asymptomatic β-ΤΜ patients receiving regular blood transfusions and iron-chelation therapy with deferoxamine (group A, n = 13), deferasirox (group B, n = 11) or deferoxamine with deferiprone (group C, n = 14) and fourteen age- and sex- matched healthy individuals were included in the study. All participants underwent ophthalmoscopy, full-field electroretinography (ERG), visual evoked potentials (VEP), multifocal electroretinography (mfERG), fundus autofluorescence (FAF) imaging and optical coherence tomography (OCT) scans. Results: Retinal pigment epithelium changes were present in two β-ΤΜ patients. Scotopic ERG demonstrated decreased a-wave amplitude in groups A, B and C (p = 0,03, p = 0,002 and p = 0,002, respectively) and decreased b-wave amplitude in groups B and C (p = 0,002 and p = 0,01, respectively) compared to controls. Photopic ERG showed delayed b-wave latency in groups A and C (p = 0,03 and p = 0,03, respectively). VEP response did not differ between groups. MfERG showed reduced retinal response density in ring 1 in groups A, B, C (p < 0,001, p < 0,001, p = 0,001, respectively) and ring 2 in group B (p = 0,02) and delayed latency in ring 5 in groups A and B (p = 0,04 and p = 0,04, respectively). Abnormal FAF images appeared in three cases and OCT abnormalities in one case, whereas no changes were observed in controls (p = 0,55 and p = 1,00, respectively). Conclusion: Full-field ERG and mfERG are more sensitive tools for detecting early retinal changes in β-TM patients compared with ophthalmoscopy, VEP, FAF imaging and OCT scans.Σκοπός της μελέτης ήταν να εκτιμηθεί ο ρόλος διαφόρων διαγνωστικών εξετάσεων στην ανίχνευση πρώιμων αλλοιώσεων του αμφιβληστροειδή ασθενών με ομόζυγη β-μεσογειακή αναιμία. Μέθοδος: Στη μελέτη συμπεριελήφθησαν τριάντα οκτώ ασθενείς με ομόζυγη β-μεσογειακή αναιμία χωρίς συμπτώματα από τους οφθαλμούς, οι οποίοι υποβάλλονταν σε συχνές μεταγγίσεις αίματος και λάμβαναν αγωγή αποσιδήρωσης με δεσφερριοξαμίνη (ομάδα Α, n=13), δεφερασιρόξη (ομάδα Β, n=11) ή συνδυασμό δεσφερριοξαμίνης με δεφεριπρόνη (ομάδα Γ, n=14) και 14 υγιείς μάρτυρες ίδιας ηλικίας και φύλου. Όλοι οι συμμετέχοντες υποβλήθηκαν σε βυθοσκόπηση και μελέτη με ηλεκτροαμφιβληστροειδογράφημα (ΗΑΓ), οπτικά προκλητά δυναμικά ινιακού λοβού (ΔΙΛ), πολυεστιακό ΗΑΓ, αυτοφθορισμό βυθού και οπτική τομογραφία συνοχής (OCT) της ωχράς κηλίδας. Αποτελέσματα: Δύο ασθενείς εμφάνισαν διαταραχές του μελάγχρου επιθηλίου στη βυθοσκόπηση. Το σκοτοπικό ΗΑΓ ανέδειξε ελαττωμένο ύψος του κύματος α στις ομάδες Α, Β και Γ (p=0,03, p=0,002 και p=0,002, αντίστοιχα) και ελαττωμένο ύψος του κύματος β στις ομάδες Β και Γ (p=0,002 και p=0,01, αντίστοιχα) σε σύγκριση με την ομάδα ελέγχου. Το φωτοπικό ΗΑΓ έδειξε παράταση του λανθάνοντα χρόνου εμφάνισης του κύματος β στις ομάδες Α και Γ (p=0,03 και p=0,03, αντίστοιχα). Η απάντηση στο μέγιστης απάντησης ΗΑΓ και στα ΔΙΛ δεν διέφερε ανάμεσα στις ομάδες. Το πολυεστιακό ΗΑΓ φανέρωσε μειωμένη αμφιβληστροειδική απάντηση στον κεντρικό δακτύλιο 1 στις ομάδες Α, Β και Γ (p<0,001, p<0,001 και p<0,001, αντίστοιχα) και στον δακτύλιο 2 στην ομάδα Β (p=0,02) και παράταση του χρόνου στον δακτύλιο 5 στις ομάδες Α και Β (p=0,04 και p=0,04, αντίστοιχα). Παθολογικές εικόνες αυτοφθορισμού εμφάνισαν τρεις οφθαλμοί και αλλοιώσεις στην OCT ένας οφθαλμός, ενώ οι μάρτυρες δεν παρουσίασαν καμία διαταραχή (p=0,55 και p=1,00, αντίστοιχα). Συμπέρασμα: Το ΗΑΓ και το πολυεστιακό ΗΑΓ είναι πιο ευαίσθητες εξετάσεις από τη βυθοσκόπηση, τα ΔΙΛ, τον αυτοφθορισμό και την OCT ωχράς κηλίδας στην ανίχνευση πρώιμων αλλοιώσεων στον αμφιβληστροειδή ασθενών με ομόζυγη β-μεσογειακή αναιμία

Investigating the Structural and Functional Changes in the Optic Nerve in Patients with Early Glaucoma Using the Optical Coherence Tomography (OCT) and RETeval System

The present manuscript introduces an investigation of the structural and functional changes in the optic nerve in patients undergoing glaucoma treatment by comparing optical coherence tomography (OCT) measurements and RETeval system parameters. For such a purpose, 140 eyes were examined at the Ophthalmology Clinic of the “Elpis” General Hospital of Athens between October 2022 and April 2023. A total of 59 out of 140 eyes were from patients with early glaucoma under treatment (case group), 63 were healthy eyes (control group) and 18 were excluded. The experimental measurements were statistically analyzed using the SPSS software package. The main outcomes are summarized below: (i) there was no statistical difference between the right and left eye for both groups, (ii) statistical differences were found between age interval subgroups (30–54 and 55–80 years old) for the control group, mainly for the time response part of the RETeval parameters. Such difference was not indicated by the OCT system, and (iii) a statistical difference occurred between the control and case group for both OCT (through the retinal nerve fiber layer–RNFL thickness) and the RETeval parameters (through the photopic negative response–PhNR). RNFL was found to be correlated to b-wave (ms) and W-ratio parameters. In conclusion, the PhNR obtained by the RETeval system could be a valuable supplementary tool for the objective examination of patients with early glaucoma

Computer-Aided Discrimination of Glaucoma Patients from Healthy Subjects Using the RETeval Portable Device

Glaucoma is a chronic, progressive eye disease affecting the optic nerve, which may cause visual damage and blindness. In this study, we present a machine-learning investigation to classify patients with glaucoma (case group) with respect to normal participants (control group). We examined 172 eyes at the Ophthalmology Clinic of the “Elpis” General Hospital of Athens between October 2022 and September 2023. In addition, we investigated the glaucoma classification in terms of the following: (a) eye selection and (b) gender. Our methodology was based on the features extracted via two diagnostic optical systems: (i) conventional optical coherence tomography (OCT) and (ii) a modern RETeval portable device. The machine-learning approach comprised three different classifiers: the Bayesian, the Probabilistic Neural Network (PNN), and Support Vectors Machines (SVMs). For all cases examined, classification accuracy was found to be significantly higher when using the RETeval device with respect to the OCT system, as follows: 14.7% for all participants, 13.4% and 29.3% for eye selection (right and left, respectively), and 25.6% and 22.6% for gender (male and female, respectively). The most efficient classifier was found to be the SVM compared to the PNN and Bayesian classifiers. In summary, all aforementioned comparisons demonstrate that the RETeval device has the advantage over the OCT system for the classification of glaucoma patients by using the machine-learning approach

Effect of carotenoids dietary supplementation on macular function in diabetic patients

Abstract Background Diabetic retinopathy is a major cause of visual impairment and blindness among working-age people worldwide. The aim of our study was to investigate the effects of a carotenoid supplementation on retinal thickness and macular function of patients with diabetes using optical coherence tomography (OCT) and multifocal electroretinography (mfERG). Methods A retrospective study of one hundred and twenty eyes of sixty patients age between 40 and 60 years with non-insulin dependent type 2 diabetes mellitus without diabetic retinopathy who underwent OCT and mfERG and took vitamin supplements for a period of two years. Patients received a carotenoid supplement containing lutein (10 mg), zeaxanthin (2 mg) and meso-zeaxanthin (10 mg) once a day for two years. The thickness of the fovea was evaluated using OCT and the macular function was tested by mfERG. Results OCT showed an increase in the central foveal thickness and mfERG revealed increased retinal response density within the central 13° surrounding the fovea (rings 1 to 3) at two years after the onset of carotenoids supplement intake. Conclusion The use of carotenoid supplements may be of benefit for improving visual function of type 2 diabetes patients. However, further study is needed to assess the treatment’s long-term efficacy

Polymorphism analysis of miR182 and CDKN2B genes in Greek patients with primary open angle glaucoma.

Glaucoma is a progressive optic neuropathy resulting from retinal ganglion cells death; it represents one of the leading causes of irreversible blindness worldwide. Although, primary open angle glaucoma (POAG) is the most common type of the disease, the pathogenesis of POAG and the genetic factors contributing to disease development remain poorly understood. The aim of this study was to investigate whether the polymorphisms rs76481776 in miR182 gene and rs3217992 in cyclin-dependent kinase inhibitor-2B (CDKN2B) gene are risk factors for POAG in a series of patients of Greek origin. A case-control study was conducted including 120 patients with POAG and 113 unaffected healthy controls of Greek origin, surveyed for polymorphisms with potential correlation to POAG. DNA from each individual was tested for the miR182 rs76481776 and CDKN2B rs3217992 polymorphisms. Regarding the miR182 rs76481776 polymorphism, the T allele occurred with significantly higher frequency in POAG patients compared to controls (OR: 2.62, 95% CI: 1.56-4.39; p = 0.0002). The CDKN2B rs3217992 A allele frequency was found significantly increased in POAG patients compared to healthy individuals (OR: 1.72, 95% CI: 1.18-2.49; p = 0.005). Therefore, both rs76481776 polymorphism in miR182 gene and rs3217992 polymorphism in CDKN2B gene seem to be associated with the development of POAG in a Greek population. The carriers of the T allele of rs76481776 in miR182 and the carriers of the A allele of rs3217992 in CDKN2B have an increased risk of developing POAG

Generalized seizures and transient contralateral hemiparesis following retrobulbar anesthesia: a case report

Background: Retrobulbar block is a local anesthetic technique widely used for intraocular surgery. Although retrobulbar anesthesia is considered to be relatively safe, a number of serious adverse events have been reported. To our knowledge, immediate onset of generalized seizures with contralateral hemiparesis after retrobulbar anesthesia has not been reported. Case presentation: A 62-year-old Caucasian healthy male with a right eye retinal detachment was admitted for pars plana vitrectomy. During retrobulbar anesthesia with ropivacaine and before needle withdrawal, the patient developed twitching of the face which rapidly progressed to generalized tonic-clonic seizures. Arterial oxygen saturation decreased to 75 %. Chin lift was performed and 100 % oxygen was administrated via face mask, which increased saturation to 99 %. Midazolam 2 mg was administrated intravenously to control seizures. After cessation of seizures, left-sided hemiparesis was evident. Brain computed tomography and electroencephalogram were normal 3 h later. The patient underwent pars plana vitrectomy under general anesthesia 4 days later. Conclusion: Serious complications of local anesthesia for ophthalmic surgery are uncommon. We present a case in which generalized tonic-clonic seizures developed during retrobulbar anesthesia, followed by transient contralateral hemiparesis. The early onset of seizures indicated intra-arterial injection of the anesthetic. Our case suggested the need for close monitoring during the performance of retrobulbar anesthesia and the presence of well-trained personnel for early recognition and immediate management of the complications