Refraction and Prescribing. Case history, record cards and recording. Monocular Subjective Refraction. Best vision sphere. Assessment of astigmatism. Binocular balancing. Binocular subjective refraction. Anisometropia. Assessment of presbyopia and the reading addition. Assessment of binocular vision and accommodation.
Ottica Visuale. F. Zeri, A. Rossetti, A. Fossetti, A. Calossi, Società editrice Universo, Roma, 2012.
Clinical Procedures in Primary Eye Care, 4th Edition, DB. Elliott, Editore: Butterworth- Heinemann, 2013
Learning Objectives
Knowledge: knowing myopia, hyperopia and astigmatism both from an etiological and refractive point of view; the correction of refractive errors, the mechanism of accommodation and its influence on near vision and the causes of presbyopia. Have a basic knowledge of binocular vision, of the interaction between accommodation and convergence and of latent and manifest deviations.
Acquired skills: to be able, after having made a thorough case history, to measure and correct the various refractive errors and presbyopia.
Skills acquired at the end of the course: knowing how to fully manage, from a technical point of view, refraction of simple visual defects myopia, hyperopia, astigmatism and presbyopia. Be able to provide the patient with the appropriate information on his correction.
Monocular refraction methods: - Anamnesis, preliminary examinations, determination of the spherical equivalent and the Best Vision Sphere (BVS) - Blurring and recession - Correction of astigmatism using the quadrant for astigmatism: procedure, checks and controls - Evaluation of the astigmatism through the use of the cross cylinder: procedure, checks and controls. - Sphere refinement test (hints): use of positive and negative lenses of 0.25 dt, bichromatic, cross reticle and cross cylinder. Accommodation biocular balance test, prismatic and polarized. Practical tests.
Binocular balances, foveal suspension, Humphriss technique.
The emmetropization process. The classification of ametropias. Axial and refractive ametropias. Classification of hyperopia in relation to accommodation. Classifications of myopia, based on type, extent, age of onset. Discussion of a clinical case and compilation of a patient card. Anisometropia: classification, causes, limits of ophthalmic correction.
The lens, accommodation, presbyopia. Methods for determining near addition: addition as a function of age, fixed cruciate cylinder, clear vision interval.
Review of the basic concepts related to the standardization of the measurement of visual acuity. Visual acuity for near. Assessment of reading skills: reading acuity, reading speed and critical print size. Visual quality questionnaires and their application in the evaluation of near correction (NAVQ questionnaire: Near Activity Vision Questionnaire).
Basic concepts on the physiology of binocular vision: axes and angles of the eye: Optical axis, Pupillary axis, Fixation axis, Line of sight, Nodal axis. Alpha angle, gamma angle, kappa angle, lambda angle. Sensory fusion, oroptero, physiological diplopia, Panum fusional area, depth perception. Stereopsis and stereoacuity. Latent and manifest ocular deviations. Classification of phorias and methods of investigation of the heterophoric state.