It all begins with CASE HISTORY

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2 It all begins with CASE HISTORY This is one of the most important procedures in any eye examination. You become the detective Ask open ended questions Let the patient tell you their story Chief Complaint Why are you here? Tell me about your eyes and your vision? Document is patient s exact words Location specifically where the problem occurs Frequency how often as this occurred Onset when does the problem typically first occur Progression how the problem begins, unfolds, resolves Duration how long the problem typically lasts Aggravating or alleviating factor what makes it worse or better Any associated symptoms or attributions what causes it Last eye Examination When By Whom Prescription history Ocular Health (i.e. cataracts, glaucoma, macular degeneration) Self Family History General Health (i.e. hypertension, diabetes) Self Family History Medication What (including over-the-counters and supplements) Allergies Medication Environmental (seasonal) Occupation/Hobbies 2

3 BLOOD PRESSURE It is the pressure caused by the blood pushing against the inside walls of the arteries as it flows through the body. Systolic Pressure First and largest number The force exerted against the arterial walls during the heart beat Diastolic Pressure Second and smaller number The force on the arterial walls when the heart is a rest Sphygmomanometer Aneroid Uses a pressure gauge and indicator on a dial Mercury Uses mercury to measure pressure How to: Determine the proper cuff size Patient should be seated, relaxes, with arm slightly flexed and supported at heart level, palm up Expose upper arm and place cuff1 inch above brachial artery pulse (inner crease of arm) Wrap cuff and secure, center arrows marked on cuff over brachial artery Locate pulse with stethoscope on brachial artery Close valve of pressure bulb Inflate cuff to 30mm Hg above patient s normal systolic level (no more than 200mm Hg) Slowly release the valve about mm Hg/second Note measurement level at which first clear sound of two consecutive beats are heard Continue deflating cuff gradual Note measurement level at which the sound disappears Wait 30 seconds if repeating Pulse Lay index and middle fingers on inner side of patient s wrist Count beats for 15 seconds Multiply by 4 = beats per minute 3

4 VISION ACUITY Chart should be well-illuminated Room light may vary according to practitioner philosophy Important that all personnel use same conditions Recommended sequence Distance without RX OD OS OU Distance with RX OD OS OU Near without RX OD OS OU Near with RX OD OS OU 4

5 PUPILLARY DISTANCE Distance PD Rest millimeter ruler on bridge of nose Close your right eye and have patient look into your open left eye Align the zero with the temporal edge of patient s right pupil Open your right eye and close your left eye Instruct patient to look into your open right eye Take reading from millimeter rule that is directly in line with nasal edge of patient s left pupil Verify that ruler has not moved Near PD Instruct patient to look at your open left eye Align zero of ruler to temporal edge of patient s right pupil Look to the patient s left eye Take measurement that intersects with nasal edge of patient s left pupil Or use Pupillometer EYE DOMINANCY Also called eye preference Have patient form a triangle with their hands, overlapping thumbs as the base or use a card with a hole in the center Stretch to full arms length Ask patient to focus on an object or an isolated letter on the acuity chart Observe which eye they focus with This is their dominate eye To verify, have them close that eye and report what they see 5

6 STEREOPSIS Is the ability to see or appreciate depth using both eyes Types of Booklets used: Titmus Stereo Fly Randot Stereo Reindeer Performed with patient s best correction in good illumination With cross polarized filters at near distance (16 inches) Measures gross stereopsis, intermediate stereopsis or fine stereopsis Measured in seconds of arc The smaller the number the finer the stereopsis Example: Gross = 3,000 seconds of arc Intermediate = 400, 200, 100 seconds of arc Fine = 40 seconds of arc 6

7 NEAR POINT OF ACCOMMODATION and CONVERGENCE Accommodation defined as focusing ability of the eyes Convergence act of the eyes turning inward toward the nose NPA is to evaluate the ability of the eyes to focus at near NPC is to measure the ability of the two eyes to work together To perform: Patient wears near spectacle prescription Use a target, such as a penlight. Hold at midline Bring target toward the patient s nose (the eyes will turn in trying to maintain single image) Instruct patient to tell you when the target becomes blurry (This point is called breaking fusion) Stop and ask patient if they can clear the image When patient can no longer clear, measure distance from target to bridge of nose This is blur point or Near Point of Accommodation Continue moving target toward nose Ask patient to try to maintain a single image Monitor patient eyes Watch for an eye to turn out When patient reports target doubles or you see one eye lose fixation This is the break point or Near Point of Convergence Record to nose for NPC Place target on nose Slowly move along midline Ask patient to report when target becomes single again This is recovery point Measure distance from bridge of nose Data is recorded as blur, break and recovery points in cm 7

8 Cover/Uncover Test Unilateral Cover Test Evaluates the alignment of the eyes Determines frequency (constant or intermittent) Unilateral or alternating How is it done? Patient wears correction Watching a single letter of acuity chart Cover right eye for 2 3 seconds Watch for movement of left eye Repeat several times Now move to left eye and repeat Also watch for movement of covered eye as removing occluder If no movement o No tropia is present Ortho If movement o If right eye moves when left eye is covered Right tropia o If left eye moves when right eye is covered Left tropia o If both eyes move when the other is covered Alternating tropia 8

9 Alternating Cover Test Determines the direction and magnitude of the tropia or phoria Eso Exo Hyper Hypo How is it done? Patient instructed to look at letter on acuity chart Cover patient s right eye Hold it for 1 second Move to left eye Observe right eye Hold for 1 second Move to right eye Observe left eye If no movement Patient is orthophoric If eye moves in to pick up fixation as uncovered Habitual position is out Patient is exophoric If eye moves out to pick up fixation as uncovered Habitual position is in Patient is esophoric If there is no movement detected on unilateral cover test but movement is noted on alternating cover test THEN. Phoria is present If movement is noted in both tests THEN Tropia is present 9

10 EXTRAOCULAR MUSCLE TESTING Broad H Pursuits Movements of eyes as they follow a moving target Saccades Jumping movements from one target to another To Perform: Face the patient, with room and target well-illuminated Patient removes eyewear Hold target approximately 40 cm directly in front of patient Instruct patient to follow the target with eyes not moving their head Starting a midline, move target horizontal to the right approximately 12 inches Then up, then down, then back to midline Move target across midline to patient s left approximately 12 inches Then up, then down, then back to midline Record as smooth and full or jerky or incomplete Use two testing targets Present targets approximately 40 cm in front of patient and approximately 30 cm apart horizontally Ask patient to look from one to the other Repeat sequence in vertical meridians and in both directions of an X pattern Record the accuracy of eye movements, whether eyes are able to locate and fixate or overshoot or undershoot 10

11 COLOR TESTING Color Vision Classifications Trichromatism normal color vision Uses three primary colors (red, green and blue) Protanolalous Red weakness Deuteranomalous Green weakness Dichromat Uses two primary colors Protanope Red deficiency Deuteranope Green deficiency Tritanope Blue-Yellow deficiency Monochromat Sees everything as the same color Also known as achromatism Pseudoisochormatic Plates Most commonly performed With correction Evaluated with lighting daylight from the northern sky Reading distance (30 inches or 75cm Give a limited amount to time for viewing Farnsworth D-15 Patient is asked to arrange the discs in color sequence 11

12 KERATOMETRY A measurement of the corneal curvature Cornea supplies approximately 2/3 of the refracting power of the eye (43.00D) To Perform: Clean and adjust keratometer eyepiece for clarity Seat patient comfortably; head should be firmly against headrest, chin in chinrest Occlude eye not being tested Release locking knob located on left side and swing instrument in front of eye to be tested Instrument can be raised or lowered until pin at side of lamp house is aligned with patient s outer canthus Patient can see an image of their own eye Adjust instrument until white circle is reflected off cornea Using focusing knob directly below eyepiece, focus circles until they are sharp and clear Circles should be aligned so the black cross is in center of lower right circle Once mires are focused, tighten locking knob Turn horizontal measuring drum (left side) until the plus signs between the two lower circles overlap If the plus signs do not align tip to tip, rotate the axis by rotating the drum Keep plus signs in sharp focus Turn vertical measuring drum (right side of instrument) Until minus signs overlap Read horizontal measuring drum (left side)and axis Read vertical drum (right side) and axis Example: OD 085 OS 005; 095 AUTO-REFRACTION Automated system to record patient s subjective refraction Can be performed on infants to seniors TOPOGRAPHY Computer generated topography mapping of front surface of cornea Includes K-Readings as from keratometry 12

13 TONOMETRY Measurement of pressure inside the eye caused by aqueous humor Increased IOP s often can be red flags in detection and treatment of glaucoma Indentation Schiotz Applanation Goldmann is most common Anesthetize the eye Apply fluorescein Clean tonometer tip Tonometer probe is positioned so it is centered on cornea Looking through slit lamp; view is of two green semicircles of fluorescein Turn knob on side of tonometer until inner edges of two semicircles touch IOP measurement is obtained when the scale reading is multiplied by 10. Non-contact Tono-Pen 13

14 VISUAL FIELDS the area or extent of physical space visible to an eye in a given position Physiologic blind spot 15 degrees temporal to fixation Represents area occupied by optic nerve head Scotoma Absolute vision absence Types of Visual Fields Kinetic Target moved from non-seeing to seeing until first detected Static Target is stationary Threshold or suprathreshold Test points are evaluated by a staircase process increasing in brightness Confrontation Visual Fields Gross evaluation of patient s visual fields To Perform: Sit approximately 2 feet in front of patient Occlude patient s left eye Close your right eye Ask patient to look into your open (left) eye Move target from periphery into patient s visual field Ask patient to respond when they see the test object Evaluate each of the four quadrants Repeat at least two times in each quadrant Record as Full to Finger Count (FTFC) or abnormal 14