This is part 3 of a 3-part video series titled "Basic Principles of Contact Lens Fitting," which discusses the principles behind contact lens selection and fitting. Soft and rigid gas permeable (RGP) lenses are discussed, including the properties of spherical and aspheric lenses, the use of diagnostic lenses, and indications and contraindications for various lens types. Each part of the clinical exam is reviewed in detail, stressing the importance of patient history, diagnostic results, and patient expectations to ensure optimal visual outcomes and patient satisfaction.

Part 1: Contact Lens Fitting: Lens Selection
Part 2: Contact Lens Fitting: Soft Lenses
Part 3: Contact Lens Fitting: Rigid Gas Permeable Lenses