NCLE Practice Test Practical Questions and Answers

Steep Fluorescein Pattern - Bright green pooling center, very faint green pooling on diameter of lens Flat Fluorescein Pattern - Bright green pooling on diameter of lens, very faint green in center Against-the-rule Astigmatism Pattern - Bright green pooling horizontally, faint green pooling vertically With-the-rule Astigmatism Pattern - Bright green pooling vertically, faint green pooling horizontally Prism Ballast - Common technique to stabilize lens from rotating. Added thickness will position lens inferiorly (bottom of cornea) Truncation - Cutting off .50mm to 1.50mm of bottom edge of lens to provide stability. Reduces diameter, making a looser fit. Double Slab-off - Lens is thicker centrally and thinner at top and bottom of lens. Provides comfort to wearer, but may cause some stability issues. Aspheric Lens Design - Hyperflange - Used to correct high riding minus lenses. Myoflange - Used to correct low riding plus lenses. Monovision - Corrects presbyopia in contact wearers. One eye uses distance (dominant) and the other eye uses reading (resessive) Segment Bifocal - Same concept as spectacle bifocal. Must be prism ballast. Often crescent shaped. Toric Lenses - Anterior (front surface), back spherical surface or posterior (back surface), toric back curve Front Toric Lens - Corrects a low to moderate amount of corneal astigmatism