Assessment of the Eye and Vision Chapter 48 Assessment of the Eye and Vision

Anatomy and Physiology Review Anatomic features of the eye.

Eye Left: Flow of aqueous humor. Right: The extraocular muscles.

Refraction Emmetropia Hyperopia Myopia Astigmatism

Pupillary Constriction Miosis Mydriasis Accommodation Miosis and mydriasis.

Assessment Patient history Nutrition history Family history and genetic risk Current health problems

Assessment (cont’d) Near vision Visual field Extraocular muscle function Color vision

Snellen Chart

Age-Related Structural Changes Decreased eye muscle tone Ectropion and dry eye Arcus senilis Corneal changes Changes in color of sclera Less ability to dilate pupil More light needed for reading

Arcus Senilis

Cataract

Age-Related Functional Changes Yellowing of lens Accommodation gradually lost Presbyopia Far point decreases Color perception decreases IOP increases

Diagnostic Tests Imaging assessment Slit-lamp examination Corneal staining Tonometry

Diagnostic Tests (cont’d) The Tono-Pen.

IOP Estimation Use of Goldman’s applanation tonometer and a slit lamp to measure IOP.

Ophthalmoscopy Proper technique for direct ophthalmoscopic visualization of the retina.

Other Diagnostic Tests Fluorescein angiography Electroretinography

Audience Response System Questions Chapter 48 Audience Response System Questions 18

Question 1 Which circumstance places the patient at the greatest risk for developing vision disturbances? History of working with computer Advanced age History of diabetes mellitus Retired construction worker Answer: C Rationale: Certain systemic diseases greatly increase the risk for developing visual problems. Diabetes mellitus and hypertension can have serious adverse effects on vision. Working with a computer can cause eye strain. Working outside can result in too much exposure to ultraviolet rays if proper eye protection is not worn. Advanced age also influences vision, but environmental factors and diseases impact vision changes associated with advanced age.

Question 2 Which is a priority nursing intervention when providing care to an older patient who has problems with vision? Review the medication administration record for artificial tears Review medications before administration Ensure adequate, nonglare lighting in the patient’s room Provide written and verbal instruction for nursing education interventions Answer: C Rationale: Several changes in the eye that occur with aging alter vision, increasing the risk for tripping or falling. Good lighting is necessary for the best vision. Color discrimination can be difficult for older patients, so medication education should include names and indications of medications, but use caution when instructing on color. Verbal and written education provide reinforcement for new information. With aging, the eye dries and artificial tears or normal saline drops can help relieve eye irritation.

Question 3 In performing a psychosocial assessment of a patient who has recently experienced vision changes, the nurse should: Provide the patient with a list of services for the visually impaired. Meet with family members or significant others to determine whether the patient can still perform ADLs. Provide opportunities for the patient and family to express their concerns about a possible change in vision status. Ask the patient if he or she has made appropriate adjustments in lifestyle to accommodate the vision changes. Answer: C Rationale: A patient who has experienced changes in visual perception may be anxious or fearful about a possible loss of vision. Visual impairment services are probably not necessary at this early stage. The patient’s ability to perform ADLs should be assessed first, with information elicited directly from the patient (not family members).