NCLE Prep Exam Part 1 of 4 Questions With Correct Answers

Which of the following medications may affect successful contact lens wear? A. Antacids B. Antihistamines C. Aspirin D. Laxatives - Answer B. Antihistimines Which term refers to a sensitivity to light? A. Prebyopia B. Photophobia C. Pannus D. Ptosis - Answer B. Photophobia The following is an example of what type of astigmatism? K's 42.50 @ 180 / 40.50 @ 90 A. With the Rule Astigmatism B. Lenticular Astigmatism C. Against the Rule Astigmatism D. Irregular Astigmatism - Answer C. Against the Rule Astigmatism This is present when the K readings are steeper i the horizontal meridian than the vertical meridian The cornea receives nutrients from: 1) Aqueous Humor 2) Tears 3) Limbal Blood Vessels 4) Orbicularis Occuli A. 1, 3 & 4 B. 2 &3 C. 1, 2 & 3 D. 3 & 4 - Answer C. 1, 2 & 3 The normal cornea is devoid of blood vessels. To provide metabolites, the cornea is nourished by diffusion of nutrients and oxygen by the aqueous humor, tears, and vascular blood vessels in the limbus. (The orbicularis occuli is a muscle in the eyelid whose primary function is lid closure) The increased loss of ability of the crystalline lens to accommodate is called: A. Presbyopia B. Myopia C. Hyperopia D. Aphakia - Answer A. Presbyopia Which instrument can provide simultaneous information about the cornea, lids, conjunctiva, lashes, contact lens surface and fit? A. Radiuscope B. Corneoscope C. Slit Lamp D. Keratometer - Answer C. Slit Lamp The slit lamp (or biomicroscope) can provide simultaneous information about the cornea, lids, conjunctiva, lashes, contact lens surface and fit. The pre-corneal tear film is composed of three layers which are: A. Lysozyme, oil, lacrimal B. Sebaceous, mucoid, BAK C. Lipid, aqueous, mucin D. Water, mucoid, lysozyme - Answer C. Lipid, aqueous, mucin The pre-corneal tear film is composed of lipid, aqueous, and mucin layers. The lipid layer is traditionally thought of as most anterior (front) while the mucin layer is most posterior (back) Transpose the following Rx into minus cylinder form: Rx -4.50 +1.25 x 94 A. -3.25 -1.25 x 4 B. -3.25 -1.25 x 94 C. -4.50 -1.25 x 4 D. -5.75 - 1.25 x 4 - Answer A. -3.25 -1.25 x 4 The average pH value of the human tear is: A. 6.6 B. 7.4 C. 7.8 D. 10.0 - Answer B. 7.4 Values higher than 7.4 are considered relatively alkaline, whereas values lower than 7.4 are considered relatively acidic If the manufacturer's guidelines suggest a minimum of 4 hours for disinfection, what would you suggest to the patient? A. Never leave lenses in disinfectant overnight B. 2 to 3 hours is probably enough C. Use surfactant cleaner and preserved saline D. A minimum of 4 hours is required - Answer D. Minimum of 4 hours required Patients should always be directed to follow the manufacturer's guidelines and not try to cut corners by leaving lenses in any solution for less than the recommended time. The main supply of oxygen to the corneal epithelium is derived from the: A. Stroma B. Collagen Fibrils C. Basal D. Tear Film - Answer D. Tear Film The cornea is exposed to the atmosphere which contains 21% oxygen. Through a process known as diffusion, oxygen from the atmosphere dissolves into tears where it can be utilized by the corneal epithelium What is the term for the condition in which there is loss of vision without any apparent disease to the eye? A. Amblyopia B. Aniridia C. Astigmatism D. Aphakia - Answer A. Amblyopia Patients are amblyopic when they are not able to attain 20/20 vision with an eye that has not experienced any disease or trauma. Aniridia is the absence of the iris. Astigmatism refers to a refractive error in which light rays do not focus in a single point. Aphakia is the absence of the crystalline lens. Which auxiliary trial lens will extend the keratometer to approximately 30.00D? A. +1.00D B. +1.25D C. -1.00D D. -1.50D - Answer C. -1.00 By placing a -1.00D lens over the aperture of the keratometer, you can extend the low range from 36.00D to 30.00D Which step should be performed first when taking keratometer measurements? A. Rotate the drum to reflect the cylinder axis B. Adjust the patient so that they are comfortable C. Focus the eyepiece D. Cover the patient's eye that is not being measured - Answer C. Focus the eyepiece The following is an example of what type of astigmatism? K's 44.00@180 / 44.50@90 Rx -3.00 -2.50 x 180 A. Lenticular Astigmatism B. Against the Rule Astigmatism C. Irregular Astigmatism D. Oblique Astigmatism - Answer A. Lenticular Astigmatism