Ως αμβλυωπία ορίζεται η υποβάθμιση της χωρικής και της στερεοσκοπικής όρασης κατά την απουσία οποιασδήποτε δομικής ή λειτουργικής ανωμαλίας του βολβού του οφθαλμού1,2 Πιο συγκεκριμένα, αποτελεί μία νευροαναπτυξιακή διαταραχή του oπτικού συστήματος, η οποία ευθύνεται για τη λειτουργική μείωση της οπτικής οξύτητας. Διαπιστώθηκε ότι οι ανώμαλες οπτικές εμπειρίες οδηγούν στην πρώιμη εμφάνιση της αμβλυωπίας κατά την παιδική ηλικία, εμπειρίες που αφορούν στην απουσία συντονισμένης ή και ισορροπημένης καταγραφής των εικόνων και από τους δυο οφθαλμούς, με συνέπεια να εντοπίζονται ελλείματα στον οπτικό φλοιό. Συνήθως  αναπτύσσεται πριν τα δύο πρώτα έτη ζωής του παιδιού, μπορεί όμως να εμφανιστεί μέχρι και το όγδοο έτος. Ως σοβαρή συνέπεια από την εμφάνιση της αμβλυωπίας είναι ότι δεν μπορεί να επέλθει πλήρης αποκατάσταση της αρχικής βλάβης2,4.

amblyvpia1

Παθοφυσιολογία Αμβλυωπίας

Είναι ευρέως αποδεκτή η άποψη οτι η αμβλυωπία προκύπτει από την έλλειψη αντιστοιχίας των εικόνων από τον κάθε οφθαλμό, γεγονός που οδηγεί στην επιλογή της εικόνας του ενός οφθαλμού έναντι της εικόνας του άλλου17. Να σημειωθεί, πως οι οπτικές εμπειρίες στη νεαρή ηλικία διαδραματίζουν σημαντικό ρόλο στην οργάνωση των τμημάτων του εγκεφάλου του ενήλικα που επεξεργάζονται τα οπτικά ερεθίσματα.

Η θεραπεία της αμβλυωπίας συμβάλλει στην αποκατάσταση της οπτικής οξύτητας του αμβλυωπικού οφθαλμού στα φυσιολογικά επίπεδα ή σε όσο το δυνατόν πιο κοντά σε αυτά. Οι κύριες μέθοδοι επίτευξης αυτής της αποκατάστασης στηρίζονται στη διόρθωση οποιασδήποτε υπάρχουσας διαθλαστικής ανωμαλίας και στην αποτροπή χρήσης του "υγιούς" οφθαλμού, ώστε να επιστρατευτεί ο "νοσούν’’ οφθαλμός για να επιτευχθεί η σωστή λειτουργία  της όρασης. 37

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Brad Bowling FRCSEd(Ophth) FRCOphth FRANZCO (Author) Kanski's Clinical Ophthalmology: A Systematic Approach, 8e 8th Edition

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