What is the Cover Test? The cover test is a basic clinical examination used to detect eye misalignment (both manifest and latent strabismus) by observing eye movement when one eye is covered. Why is it important? Detects manifest deviation (Tropia) Detects latent deviation (Phoria) Essential for assessing binocular vision Helps in early diagnosis of strabismus Types of Cover Test Cover–Uncover Test One eye is covered at a time Detects manifest strabismus (Tropia) Observation: If the uncovered eye moves → a manifest deviation is present Alternate Cover Test The cover is rapidly alternated between the eyes Breaks binocular fusion Observation: Movement appearing → indicates a latent deviation (Phoria) What do we observe? Eye movement (inward / outward / vertical) Speed and stability of refixation Direction of deviation Presence of suppression Clinical Note ESO → the eye moves outward to fixate EXO → the eye moves inward to fixate Helps differentiate between esotropia, exotropia, hypertropia, and hypotropia Important Tip It is preferable to perform the test at both distance (6 meters) and near (33–40 cm) for a more accurate diagnosis. For the lecturer M.M. Muhaimin Sameer Arif University of Al-Mustaqbal – The First and Leading Private University