Combination Effect of Optical Defocus and Low Dose Atropine in Myopia Control

The purpose of the study is to investigate the combination effect of optical defocus and low dose atropine on myopia control in schoolchildren.

Inclusion Criteria: * Age at enrollment: 7 to 12 years * Ethnicity: Hong Kong Chinese * Myopia: -0.75D (in spherical equivalent) or above in both eyes * Astigmatism: -1.50D or less in both eyes * Anisometropia: 1.50D or less (in spherical equivalent) between two eyes * Best corrected monocular visual acuity (VA): 0.04 logMAR or better * Ocular health: No abnormalities in both internal and external ocular health * Systemic health: No abnormalities such as cardiac and respiratory diseases * Binocular vision: No strabismus, diplopia, suppression and other binocular abnormalities * Normal colour vision * No previous refractive surgery or use of myopic control interventions, such as atropine, orthokeratology, and specialized spectacle lenses and contact lenses for myopic control * Able to wear the prescribed spectacles * No known allergy to atropine Exclusion Criteria: * Eye disease or binocular vision problems (e.g., strabismus, amblyopia, oculomotor nerve palsies, corneal disease, etc.) * Previous intraocular or corneal surgery * Colour vision deficiencies * Systemic disease that may affect vision, vision development (e.g. diabetes mellitus, hypertension, Down syndrome, etc.) * Systemic disease that are contradictory to atropine (e.g. asthma, cardiac diseases, etc.) * Previous gas permeable, soft bifocal, or orthokeratology contact lenses wear or bifocal / progressive addition lens spectacles wear or use of atropine or pirenzepine (longer than one month of usage) * Previous or current participation in myopia control studies * Allergy to cyclopentolate hydrochloride or atropine