The Sensory System PDF

Presented By: Mrs. Keron Jones-Fraser, RN, BScN, Cert. Nsg. Ed. MScN, PhD candidate 1. Review significant eye & ear structures and describe their functions. 2. Identify diagnostic tests for assessment of vision and evaluation of visual abilities & hearing. 3....

Presented By: Mrs. Keron Jones-Fraser, RN, BScN, Cert. Nsg. Ed. MScN, PhD candidate 1. Review significant eye & ear structures and describe their functions. 2. Identify diagnostic tests for assessment of vision and evaluation of visual abilities & hearing. 3. Discuss clinical features, diagnostic assessment and examinations, medical or surgical management, and nursing management of ocular & hearing disorders. 4. Describe therapeutic effects of ophthalmic medications  Visual acuity  Snellen chart  Record each eye  20/20 means the patient can read the “20” line at a distance of 20 feet  Finger count or hand motion  Note any evidence of irritation, inflammatory process, discharge, etc.  Assess eyelids and sclera  Assess pupils and pupillary response; use darkened room  Note gaze and position of eyes  Assess extraocular movements (eye muscles)  Ptosis: drooping eyelid  Nystagmus: oscillating movement of eyeball  Slit-lamp examination  Color vision testing- ability to differentiate colours has a dramatic effect on the activities of daily living. Eg inability to differentiate between traffic light colours  Opthalmoscopy is an examination in which the doctor uses a handheld device to look directly through the pupil (the opening in the colored iris) into the eye. This procedure is done to examine the optic nerve (seen as the optic disc) at the back of the eye.  Ultrasonography used to identify orbital tumours, retinal detachment, etc.  Gonioscopy is done by numbing the eye with anesthetic drops and placing a special type of thick contact lens with mirrors inside on the eye. The mirrors enable the doctor to view the interior of the eye from different directions. The purpose of this test is to examine the filtering angle and drainage area of the eye. In this procedure, the doctor can determine whether the angle is open or narrow.  Visual acuity test. This eye chart test measures how well you see at various distances. A tonometer measures pressure inside the eye to detect glaucoma.  Visual field test. This test measures your side (peripheral) vision. It helps your eye care professional tell if you have lost side vision, a sign of glaucoma.  Refractive errors  Can be corrected by lenses which focus light rays on the retina  Emmetropia: normal vision  Myopia: nearsighted  Hyperopia: farsighted  Astigmatism: distortion due to irregularity of the cornea  The term glaucoma is used to refer to a group of occular conditions characterised by optic nerve damage.  Family history of glaucoma  Thin cornea  Cardiovascular disease  Eye trauma  Prolonged use of systemic or topical corticosteroids  Open Angle Glaucoma usually bilateral , but one eye may be more severely affected than the other.  Primary open angel glaucoma: Optic nerve damage, visual field defects, IOP > 21 mmHg. Usually no symptoms, but possible occular pain, headaches and halos.  Normal tension glaucoma: IOP