Ophthalmologists

Georgopoulos Minas Md Pgdip Febo Frcophth Febos-Glaucoma is a Consultant Ophthalmic Surgeon, maintaining private clinics in Piraeus and Athens. He is a diplomate of the Royal College of Ophthalmologists of Great Britain (FRCOphth), having passed the requisite examinations. He holds the position of Director of the Glaucoma and Cataract departments at the Surrey and Sussex hospitals in the United Kingdom, specializing in Cataract surgery, myopia LASER treatments, Glaucoma, and anterior segment diseases. He is among the few ophthalmologists across Europe to have obtained the FEBOS-Gl title from the European Glaucoma Society (EUGS) and the European Board of Ophthalmology (EBO). He graduated from the Medical School of Democritus University of Thrace (2009) and specialized in ophthalmology at hospitals in Great Britain, acquiring the Specialist Ophthalmologist title (2016). In 2016, he became a diplomate of the European Board of Ophthalmology (FEBO), excelling in examinations held in Paris, followed by subspecialty training in glaucoma surgery at Buckinghamshire hospitals (2016-17) and the world-renowned Queen Victoria Hospital (2017-18) as a Fellow in Glaucoma and anterior segment diseases. Since April 2018, he has served as the director of the Glaucoma and Cataract departments at Surrey and Sussex hospitals in Great Britain. Additionally, he was a Visiting Consultant at Spire Gatwick Park Hospital in London. In 2020, he graduated with distinction from his postgraduate studies in Refractive Surgery and Cataract under Professor Dan Reinstein, University of Ulster. He regularly attends and lectures at international conferences and symposia. With experience from thousands of surgeries, he has permanently returned to Greece, where he maintains a clinic in Piraeus and provides his expertise at affiliated clinics in Athens.

Florou Xrysoula is an Ophthalmic Surgeon and operates a Private Clinic in Pangrati. She is a graduate and holds a PhD from the Medical School of the National and Kapodistrian University of Athens, specializing in Ophthalmology. She has worked as a resident ophthalmologist at the Links vom Rhein clinic in Cologne, the Penteli Children's General Hospital in Athens, and the General Hospital "G. Gennimatas" in Athens. Subsequently, she served as an assistant ophthalmologist at the Glyfada Health Center. Alongside her private practice, she is a collaborator at the Eye Day Clinic. She has also participated in national and international conferences with posters and oral presentations of her work and has published articles in international scientific journals. Finally, she is a member of the Hellenic Society of Intraocular Lenses and Refractive Surgery, the European Society of Cataract and Refractive Surgery, the American Academy of Ophthalmology, the Hellenic Society of Vitreoretinal Diseases, and the Hellenic Ophthalmological Society.

Kaltsos Konstantinos is an Ophthalmologist with a private practice in Thessaloniki. He holds a PhD from the Medical School of Aristotle University of Thessaloniki and specializes in ophthalmic surgery and myopia laser treatment. Dr. Kaltsos has worked in several hospitals in Greece and abroad, including AHEPA Hospital and Moorfields Eye Hospital in London. He has extensive experience in cataract and glaucoma surgery, laser vision correction, and diseases of the macula and retina. Furthermore, Ophthalmologist Kaltsos Konstantinos is a member of prominent medical associations and actively participates in seminars and conferences to remain continuously updated on advancements in his field and to provide the most modern services to his patients.

Makridakis Dimitrios MD is an Ophthalmic Surgeon with a private practice in Chalkida. The physician specialized at the General State Hospital of Athens "G. Gennimatas" and possesses extensive experience in myopia laser treatment, cataract surgery, and intravitreal injections. In his fully equipped clinic, comprehensive examination and treatment of refractive errors (myopia, hyperopia, astigmatism, presbyopia) are performed for both children and adults, along with glaucoma evaluation and treatment using visual field testing, strabismus and amblyopia assessment, fundoscopy for acquired and hereditary macular diseases, diagnosis and treatment of corneal conditions and anterior and posterior segment inflammations, diabetic retinopathy and age-related macular degeneration management, as well as license renewals.

Gkountis Xristoforos is a Ophthalmic Surgeon who maintains a private practice in Ilioupoli. He is specialized in cataract microsurgery, refractive surgery for the correction of myopia, hyperopia, and astigmatism using the latest generation laser technology, and in treatment with Collagen Cross Linking for keratoconus. He has served as a scientific collaborator at the 1st University Ophthalmology Clinic of Athens at the General Hospital of Athens "G. Gennimatas" and at the 401 General Military Hospital of Athens. Finally, he performs surgical procedures at reputable hospitals and clinics, such as the "OMMA" Ophthalmology Institute of Athens and the Athens Refractive Laser Center.

Nikitopoulos Georgios is a Pediatric and Adult Ophthalmic Surgeon maintaining private practices in Patissia and Nea Penteli. He studied at the Medical School of the National and Kapodistrian University of Athens and obtained the Ophthalmology specialty title following successful examinations, having previously specialized at the "Agia Sofia" Children's Hospital and the General State Hospital of Athens-KOFKA. Since 1988, he has been a member of the Surgical Team led by the ophthalmology professor at Cornell University in New York, Mr. M. Tragakis, specializing in the Cornea and Corneal Transplantations. He is an Anterior Segment Surgeon with an emphasis on modern small-incision cataract surgery, glaucoma, strabismus, and specialization in Lasers (correction of myopia, hypermetropia, astigmatism, presbyopia with Amaris 750S, the most advanced laser device today and unique in Greece). He also deals with the diagnosis and treatment of retinal diseases (Diabetic Retinopathy, Macular Diseases, etc.). He serves as a scientific collaborator of the 1st Ophthalmology Clinic of "Errikos Dynan" Hospital, the "Ypapanti" Ophthalmology Clinic, the "OMMA" Ophthalmologic Institute, as well as the "Athena Refractive Center." Finally, he has published 26 scientific papers at national and international ophthalmological conferences and has participated in round tables, clinical workshops, and as an instructor in experimental surgeries for younger colleagues.

Dr. Vouvouras Thomas is an Ophthalmologist with a private practice in Agios Dimitrios. He graduated from the Medical School of the University of Craiova and completed his specialization in ophthalmology at Melissia General Hospital "Amalia Fleming" and the General Hospital "Red Cross". His private clinic is fully equipped with state-of-the-art technology, and he provides a range of medical services including fundoscopy, refraction assessment, glaucoma screening, cataract evaluation, macular examination, tonometry, gonioscopy, removal of foreign bodies from the eye and eyelids, myopia and astigmatism laser treatment, hypermetropia laser, presbyopia laser, keratoconus laser treatment, and surgical interventions for retinal detachment repair. Additionally, Dr. Vouvouras has performed a significant number of surgeries to treat ophthalmic conditions, including corneal transplantation, surgical restoration of obstructed lacrimal ducts (dacryocystorhinostomy), and ultrasound-assisted cataract surgery.

Dr Karamitsos Athanasios MD, MSc, PhD, FEBO is an Ophthalmic Surgeon who maintains a private practice in the center of Thessaloniki. He holds a doctorate from the Medical School of Aristotle University of Thessaloniki and a postgraduate degree in Nanosciences and Nanotechnologies with a distinction from the same university. He has specialized for five years in the United Kingdom at the University Hospitals of Cambridge and Newcastle, focusing on diseases of the ocular fundus and specialized surgeries of the retina and macula, complex cataract surgeries, laser treatments, as well as ophthalmic inflammations and their therapies. He also has significant experience with rare ophthalmic cases and syndromes, such as Stickler syndrome. Additionally, he has specialized in OCT technology, Optical Coherence Tomography. Currently, he works as a University Fellow at the 2nd University Clinic of Aristotle University of Thessaloniki, specifically in the Department of Retinal Surgery, treating patients with macular disease, diabetic retinopathy and edema, epiretinal membrane, macular hole, intravitreal hemorrhage, and complex cataract cases. Finally, Dr Karamitsos actively participates with presentations at numerous Greek and international conferences and is a member of the Medical Association of Thessaloniki, the European Society of Cataract and Refractive Surgeons, the European Vitreoretinal Society, and the Royal College of Ophthalmologists.

Andriopoulos Georgios is an ophthalmic surgeon who maintains a private practice in the Ampelokipoi area. Upon completion of his medical studies, he specialized at the General Hospital of Patras and at the Konstantopouleio - G.N. N. Ionias - Patision Agia Olga, where he gained extensive experience in the surgical management of cataracts, eyelid surgery, glaucoma monitoring and surgery, as well as in ocular surface diseases and dry eye syndrome. In 2022, he commenced his doctoral dissertation at the Medical School of the University of Ioannina. He has participated in a significant number of international and national conferences. In 2025, he completed his subspecialty training in refractive surgery at the University of Crete. Finally, he is a member of the Hellenic Ophthalmological Society, the Hellenic Society of Intraocular Lenses and Refractive Surgery, and the Hellenic Society of Ocular Surface and Dry Eye.

Dr. Sxoinas Mixail is an Ophthalmologist with a private practice in Thessaloniki. He graduated from the Medical School of Aristotle University of Thessaloniki and specialized in Ophthalmology at the Ophthalmology Clinic of the General Hospital of Thessaloniki "Georgios Papanikolaou." He is a Scientific Associate of the General Hospital of Thessaloniki "Georgios Papanikolaou" and a regular collaborator of the General Clinic of Thessaloniki, the Athens Center, the Thessaloniki Ophthalmology Clinic, and the Therapeutic Institute "Hygeia." He has extensive experience in refractive surgery (laser correction of myopia/hyperopia), cataract surgery, and keratoconus, and has managed a wide range of conditions including astigmatism, cataract, myopia, presbyopia, hyperopia, and glaucoma. He actively participates in numerous conferences in Greece and abroad as part of his continuous professional development. Finally, he is a member of the Thessaloniki Medical Association, the Northern Greece Ophthalmological Society, the Panhellenic Ophthalmological Society, and the Hellenic Society of Intraocular Lenses and Refractive Surgery.

Ο Αιμιλιανός Στράτος είναι Χειρουργός Οφθαλμίατρος και διατηρεί το ιατρείο του εντός του Πολυϊατρείου Central Medical Park στην Καλλιθέα. Είναι πτυχιούχος της ιατρικής σχολής του Εθνικού και Καποδιστριακού Πανεπιστημίου Αθηνών καθώς και απόφοιτος του τμήματος Οπτικής των ΤΕΙ Αθηνών. Έλαβε τον τίτλο της ειδικότητάς του το 2014 κατόπιν ειδίκευσης στο Οφθαλμιατρείο Αθηνών και κατέχει τον τίτλο «Fellow του Ευρωπαϊκού Συμβουλίου Οφθαλμολογίας» (FEBO) μετά από εξέταση από το Ευρωπαϊκό Συμβούλιο της Οφθαλμολογίας (European Board of Ophthalmology-ΕΒΟ) το 2013. Το 2018 έλαβε την άδεια εκτέλεσης υπερήχων στην ειδικότητα της οφθαλμολογίας μετά από εξέταση της επιτροπής του Υπουργείου Υγείας. Επιπλέον, είναι κάτοχος Μεταπτυχιακού Διπλώματος Ειδίκευσης (Master of Science, MSc) από το διατμηματικό πρόγραμμα "Οπτική και Όραση" του Πανεπιστημίου Κρήτης. Στην διάρκεια του μεταπτυχιακού προγράμματος ο ιατρός απέκτησε σημαντική εμπειρία στην διαθλαστική χειρουργική ως μέλος της ερευνητικής ομάδας του Βαρδινογιάννειου Εργαστηρίου Μεταμοσχεύσεων και Μικροχειρουργικής του Οφθαλμού (ΒΕΜΜΟ, VEIC) στο Πανεπιστήμιο Κρήτης. Διαθέτει πληθώρα δημοσιεύσεων σε ξενόγλωσσα επιστημονικά περιοδικά αλλά και ένα σημαντικό αριθμό ανακοινώσεων σε ελληνικά και διεθνή συνέδρια οφθαλμολογίας. Μετά την λήψη της ειδικότητας ο ιατρός παρέμεινε για δύο χρόνια στο Οφθαλμιατρείο Αθηνών, όπου απέκτησε σημαντική κλινική και χειρουργική εμπειρία. Την διετία 2016 - 2018 εργάστηκε ως Επιμελητής Β' στο Κέντρο Υγείας Σπάτων με την ταυτόχρονη συμμετοχή του στις δραστηριότητες της Β' Οφθαλμολογικής κλινικής του Οφθαλμιατρείου Αθηνών. Τα πεδία ενδιαφέροντός του στην οφθαλμολογία, αφορούν την αντιμετώπιση παθήσεων των βλέφαρων και της δακρυϊκής συσκευής, των παθήσεων του προσθίου ημιμορίου όπως οι κερατοειδοπάθειες και ο καταρράκτης. Έχει επίσης εμπειρία στην αντιμετώπιση του γλαυκώματος καθώς και παθήσεων του αμφιβληστροειδούς, όπως, π.χ. στην αντιμετώπιση της εκφύλισης της ωχράς κηλίδας με ενδοβολβικές ενέσεις Ant-VEGF παραγόντων.

Kardara Eugenia MD is an Ophthalmologist who maintains a private practice in Vrilissia. She holds a degree from the University of Debrecen in Hungary and is specialized in ophthalmic surgery at the Athens Anti-Cancer Oncology Hospital "Agios Savvas." The doctor has worked in hospitals in Greece and abroad, such as "Erythros Stavros" and Dr. Agarwal's Eye Hospital clinic in India. She has extensive experience in the treatment of myopia, astigmatism, presbyopia, glaucoma, hypermetropia, chalazion, color blindness, strabismus, macular degeneration, pterygium, and cataract. Ophthalmologist Kardara Eugenia provides services including blepharoplasty, myopia laser treatment, fundoscopy, refractive error assessment, glaucoma screening, cataract evaluation, visual field testing, macular examination, retinoscopy for pediatric refractive errors, and tonometry. Finally, she has participated in numerous Greek and international ophthalmology conferences with papers and presentations on the lacrimal system, thyroid eye disease and its management, as well as the surgical reconstruction of eyelid tumors.

Vergados Athanasios is an Ophthalmologist and maintains a private clinic in Ampelokipoi. Upon completing his medical studies, he specialized at the First University Ophthalmology Clinic (G. Gennimatas - KOFKA). In May 2014, he was awarded a PhD in Ophthalmology for his research project titled "Preperimetric lesions in pseudoexfoliative Glaucoma" from the Medical School of the University of Athens. Subsequently, he further specialized in the United Kingdom at the second largest ophthalmologic hospital in Europe (Birmingham and Midland Eye Centre). Following his specialization, he was appointed Director of the Glaucoma Department at the James Paget University Hospital in the East Anglia region. In 2017, he moved to London, where he was appointed at Barts Health NHS Trust, the largest hospital complex in England. He worked as a glaucoma specialist at Whipps Cross University Hospital and was head of the Glaucoma and Emergency Department. He also served as the lead physician for glaucoma treatment at Newham University Hospital. He is a member of the Royal College of Ophthalmologists (UK), GMC (UK), UKEGS (member of the United Kingdom Glaucoma Society), BEECS (British Emergency Eye Care Society), British Ophthalmic Anaesthesia Society. Additionally, he is a member of the Athens Medical Association, the Hellenic Ophthalmological Society, and the European and Hellenic Glaucoma Societies.

Mpanteka Marina is an Ophthalmic Surgeon - Pediatric Ophthalmologist who maintains a private practice in Trikala. She has received additional training and specialization in Pediatric Ophthalmology and Strabismus in Children and Adults at the internationally renowned Moorfields Eye Hospital, London, UK, where she worked as a paid fellow, gaining extensive experience in pediatric ophthalmology cases, strabismus, amblyopia (lazy eye), keratoconus, pediatric cataract, pediatric glaucoma, and nasolacrimal duct obstruction. Simultaneously, she trained in LASER correction for myopia, astigmatism, hypermetropia, and adult cataract surgery. Since 2016, she has been the Scientific Head of the Pediatric Ophthalmology and Strabismus department at JuniorVision within the LMVision (Laser and Microsurgery Vision) Day Care Unit based in Thessaloniki. Since 2019, she collaborates with the 1st University Ophthalmology Clinic of Aristotle University of Thessaloniki and is responsible for the pediatric ophthalmology clinic at AHEPA Hospital. She is certified by the European Board of Ophthalmology (Fellow of the European Board of Ophthalmology) and is a graduate of the Medical School of Aristotle University of Thessaloniki, with postgraduate studies in Clinical Applications of Molecular Medicine. She is very actively involved in clinical research, and her notable research experience is reflected in numerous scientific publications in international ophthalmology journals, as well as many presentations at conferences in both Greece and abroad, where she frequently participates.

Maria Aleksaki is an ophthalmic surgeon and collaborator at the Aktina Center in Chalandri and Athens. She graduated from the University of Patras Medical School with honors and specialized at the Athens Eye Hospital. During her specialization, she gained experience in diseases of the macula, cornea, glaucoma, ocular inflammations, refractive surgeries, cataract operations, and the entire spectrum of emergency ophthalmology cases. As a collaborator of the Aktina Center, under the scientific supervision of Mr. Liarakos (a specialist in corneal diseases), she has expertise in refractive surgeries, monitoring and management of keratoconus, cataract surgery using the modern phacoemulsification technique, and the implantation of multifocal and toric lenses for the correction of myopia, hyperopia, astigmatism, and presbyopia. Additionally, she manages cases involving the removal of pterygium, chalazion, and papillomas.

Toulia Paraskeui MD, FEBO is an Ophthalmologist who maintains a private practice in Agia Paraskevi. She is a graduate of the Medical School of the National and Kapodistrian University of Athens, specializing in ophthalmology. In her private practice, every patient, regardless of age, can receive information regarding optic neuropathies and their management. She provides services such as refractive assessment, fundoscopy, tonometry, glaucoma screening, cataract and macular degeneration evaluation, retinoscopy for refractive errors in children, and contact lens fitting. Additionally, working at the Athens Eye Clinic, the ophthalmologist has gained clinical and surgical experience in surgical cases while also focusing on pediatric ophthalmology and the management of diabetic eye disease using new techniques. To date, she has participated in numerous seminars, conferences, and workshops, investing in the continuous education in her field of specialization. Finally, she was awarded first prize in the examinations for the trainee courses of the Hellenic Ophthalmological Society.

Orfanidis Thomas is an Ophthalmologist with a private practice in Chaidari. He graduated from the Medical School of the University of Crete and completed his Ophthalmology residency at the Ophthalmology Department of the Athens Polyclinic. He specializes in refractive surgery, including cataract surgeries using phacoemulsification, laser procedures for the correction of myopia, hyperopia, and astigmatism, as well as glaucoma investigation and monitoring. Additionally, Dr. Orfanidis has served as a collaborator at the Research Institute of Optics and Vision of the University of Crete, working alongside Professor I. Pallikari.

Dr. Mendrinos Eustratios graduated from the Faculty of Medicine at the University of Liège in Belgium with Highest Distinction. He specialized in ophthalmology at the University Hospital of Geneva, Switzerland, where he also earned his Doctorate from the Faculty of Medicine at the University of Geneva. He worked as a Consultant in the Department of Retinal, Vitreous, and Macular Diseases and Surgery at the University Hospital of Geneva, and subsequently at the University Hospital of Liverpool, England, under the direction of the world-renowned ophthalmic surgeons Professor K. Pournaras and Prof. H. Heiman, respectively. He is the author of 35 articles in international scientific journals, as well as 18 chapters in English and French ophthalmology books, and has delivered over 90 presentations at Greek and international ophthalmology conferences. He holds the European Board of Ophthalmology diploma and has been awarded for his scientific work at international conferences. Dr. Mendrinos has participated in international studies (Excite, Mont Blanc, Cabernet, VIEW2) that established the modern management of age-related macular degeneration. He is the founder and administrator of the Medica Polyclinic in Agios Stefanos, where he currently practices, a state-of-the-art facility covering nearly all specialties. Additionally, he is affiliated with the Athens Medical Center in Marousi and the OMMA Ophthalmology Clinic.

Ο Δρανίδης Γεώργιος είναι Οφθαλμίατρος και διατηρεί ιδιωτικό ιατρείο στη Θεσσαλονίκη. Είναι Διδάκτωρ και απόφοιτος της Ιατρικής σχολής του Αριστοτελείου Πανεπιστημίου Θεσσαλονίκης και μέλος του Ιατρικού Συλλόγου Θεσσαλονίκης. Ξεκίνησε την ειδικότητα του στην Οφθαλμολογία στο Γενικό Νοσοκομείο του Κιλκίς στη συνέχεια στην πανεπιστημιακη κλινική του Γενικού νοσοκομείου "Παπαγεωργίου "και την ολοκλήρωσε στο Γενικό Νοσοκομείο «Θριάσειο» της Ελευσίνας.

Στη συνέχεια, μετεκπαιδεύτηκε στο τμήμα Κερατοειδούς - Διαθλαστικής Χειρουργικής και Οφθαλμοπλαστικής Χειρουργικής και Τράπεζας Οφθαλμών του Queen Victoria Hospital στο East Grinstead στη Μεγάλη Βρετανία.

Κατόπιν εκπαιδεύτηκε στο Βαρδινογιάννειο Εργαστήριο Μεταμοσχεύσεων και Μικροχειρουργικής του Οφθαλμού (Β.Ε.Μ.Μ.Ο) του Πανεπιστημίου Κρήτης, υπό τον καθηγητή

Ι. Παλλήκαρη, εμπνευστή της μεθόδου LASIK για την διόρθωση των διαθλαστικών σφαλμάτων- μυωπία,αστιγματισμος,υπερμετρωπία και στην διορθωση της πρεσβυωπίας, καθώς και του κερατοκωνου.

Επίσης, εκπαιδεύτηκε στη Μ. Βρετανία στη χρήση βοτουλινικής τοξίνης για την εξάλειψη των ρυτίδων του προσώπου και τη θεραπεία του βλεφαρόσπασμου καθώς και στην εφαρμογή ενέσιμων σκευασμάτων υαλουρονικού οξέος για την εξάλειψη των ρυτίδων και ουλών του προσώπου.

Ο ιατρός ασχολείται με την αντιμετώπιση παθήσεων της ωχράς κηλίδας (ωχροπάθειες υγρού και ξηρού τύπου και διαβητικό οίδημα της ωχράς ή μετά από θρομβώσεις), με την χορήγηση των νέων αντιαγγειογενετικών παραγόντων (αντι - VEGF) και lasers. Στο πλήρως εξοπλισμένο οφθαλμολογικό ιατρείο του, δραστηριοποιείται σε όλο το φάσμα της Οφθαλμολογίας. Διαθέτει ειδικό εξοπλισμό για τη διάγνωση και παρακολούθηση όλου του φάσματος των Οφθαλμολογικών παθήσεων.΄Εχει πολυετή εμπειρία( σε Ελλάδα και Ηνωμένο βασίλειο) στην διόρθωση μυωπίας, υπερμετρωπίας και αστιγματισμού με Laser (LASIK - PRK), καθώς και στην αντιμετώπιση παθήσεων του κερατοειδούς - όπως του κερατόκωνου- με την επέμβαση Cross - Linking. Έχει εκπαιδευτεί στην χειρουργική αφαίρεση του καταρράκτη με φακοθρυψία και στην ένθεση ειδικών ενδοφακών (τωρικών) για την διόρθωση υψηλών αμετρωπιών (πολύ μεγάλης μυωπίας και αστιγματισμού).Διαθέτει αξιόλογη ερευνητική εμπειρία αποτελούμενη από συμμετοχές σε σε συνέδρια και workshops στην Ελλάδα και το εξωτερικό και συγγραφή πολλών επιστημονικών εργασιών.Διαθέτει αξιόλογη ερευνητική εμπειρία αποτελούμενη από συμμετοχές σε σε συνέδρια και workshops στην Ελλάδα και το εξωτερικό και συγγραφή πολλών επιστημονικών εργασιών.

Τέλος, ο ιατρός είναι μέλος της European Society of Cataract and Refractive Surgery, της Ελληνικής Οφθαλμολογικής Εταιρείας, της Ελληνικής Εταιρείας Ενδοφακών και Διαθλαστικής Χειρουργικής, του European Board of Ophthalmology, αλλά και του British Medical Council.

Το ιατρείο διαθέτει τον εξής εξοπλισμό:

OCT- Οπτική τομογραφία συνοχής

Oπτικά πεδία - Αυτόματο περίμετρο

Ψηφιακή φωτογραφία βυθού του οφθαλμού

Αυτόματο κερατοδιαθλασίμετρο

Τοπογραφία κερατοειδούς

Σχισμοειδής λυχνία

Αυτόματο φακόμετρο

Πίνακας οπτοτύπων

Παχυμετρία κερατοειδούς

Τονόμετρο Goldmann

Δοκιμαστικοί σκελετοί- ενηλίκων και παιδιών

Ειδικός εξοπλισμός για παιδοοφθαλμολογικό έλεγχο