Tutorelizabeth

background information on lead give examples of "lead-based paint hazards" and other common sources of lead in residential environments. - surfaces that are chewed or mouthed peeling paint chipping paint soil hazards friction surface impact surface common sources of lead in residential environments - windows doors floors bare soil background information on lead hazards that typically exist in residential environments - lead dust lead contaminated soil peeling, chipping paint f...

1. The sagittal depth of a rigid gas permeable contact lens can be altered without changing the diameter by: A. Changing the power B. Changing the edge design C. Changing the radius of curvature of the anterior optical zone D. Changing the radius of curvature of the posterior optical zone -AnswerThe answer is D. The posterior optical zone will directly affect the lens to cornea relationship of a rigid gas permeable lens. If the posterior optical zone is steepened, it will increase the s...

Diffused Illumination -Answer-Uses widest slit, longest aperture -Light source positioned at an angle of 40º-50º -Used to view overall areas, to observe the ocular adnexa, cornea, sclera, lids, conjunctiva, lens surface, and CL fitting characteristics Direct Illumination -Answer-Most important/useful illumination -Light source positioned at an angle of 40º-50º to oculars -Light beam and oculars are focused in coincidence on area being evaluated -The difference in the illumination is ...

optic zone -Answerthe central portion of a contact lens which contains the refractive power and generally corresponds to the central corneal cap posterior apecal radius -Answerthis term is generally used in reference to spin-cast soft lenses. the curvature of the posterior surface of the lens changes with the refractive power. the radius of curvature is measured at the apex of the posterior surface. steeper base curve -Answeroccurs when the posterior radius of curvature is decreased (i.e...

adnexa -Answerextraocular structures of the eye which include the eyelids, the orbit, lacrimal glands anterior chamber -Answerthe area bounded in front by the cornea and in the back by the lens and filled with aqueous aqueous -Answera clear, watery solution in the anterior and posterior chambers artery -Answerthe vessel supplying blood to the eye canal of schlemm -Answerthe passagewa

base curve -Answerrefers to the radius of curvature of the central posterior surface of the lens. It may be expressed in diopters of surface power (D) or in millimeters (mm) of radius or curvature. optical zone -Answerthe chord diameter over which the base curve extends on the posterior surface of the contact lens, described in millimeters secondary or intermediate curves -Answerlies between the base curve and the peripheral curve on the posterior lens surface, usually 0.70mm to 1.50mm...

Steep Fluorescein Pattern -Answer Bright green pooling center, very faint green pooling on diameter of lens Flat Fluorescein Pattern -Answer Bright green pooling on diameter of lens, very faint green in center Against-the-rule Astigmatism Pattern -Answer Bright green pooling horizontally, faint green pooling vertically With-the-rule Astigmatism Pattern -Answer Bright green pooling vertically, faint green pooling horizontally Prism Ballast -Answer Common technique to stabilize

A Correct Statement regarding epithelial cells is that they: a)Comprise the posterior layer of the cornea b)Are unable to regenerate c)Comprise the thickest layer of the cornea d) Have the ability to reproduce - Answerd) have the ability to reproduce Which of the following prescriptions indicates against-the-rule astigmatism? a)-4.50 +1.00 x75 b)-4.50 +1.00 x 180 c)-4.50 -1.00 x 165 d)4.50 -1.00 x 180 - Answera)-4.50 +1.00 x75 When a keratometer is being calibrated, which of the follow...

The tolerance for the overall lens diamter according to the ANSI standards is: A. +/-0.005mm B. +/-0.05mm C. +/-0.01mm D. +/-0.1mm -AnswerB. According to the ANSI standards (Z80.2-1989), the tolerance for the overall diameter of a contat lens is +/-0.05mm. ANSI standards have been developed to maintain quality in the contact lens industry. It is important to have an understanding of the ANSI guidelines. All of the following will enable the practitioner to verify the overall rigid gas ...

Which of the following medications may affect successful contact lens wear? A. Antacids B. Antihistamines C. Aspirin D. Laxatives -AnswerB. Antihistimines Which term refers to a sensitivity to light? A. Prebyopia B. Photophobia C. Pannus D. Ptosis -AnswerB. 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 Astigmatis