Method of illumination Direct o Character of aperture Wide open o Typical

Method of illumination direct o character of aperture

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Method of illumination: Direct o Character of aperture: Wide open o Typical magnification: 5-45x o Angle of illumination: ~60 o - 90 o o Filter: Neutral density VAN HERRICK TECHNIQUE For examination of depth of anterior chamber (useful for diagnosis of glaucomatous processes) Qualitative Evaluation of Angle of Anterior Chamber TECHNIQUE o Method of illumination: Direct o Character of aperture: Narrow beam (close to limbus) o Typical magnification: Medium o Angle of illumination: ~60 o o Filter: Neutral density In slit lamp, view ant to post -Examine 3 regions (L, mid, R) -Point of reference:thickness of slit light -Thickness on L and R side should be the thickness of the anterior chamber (if same =1x) -Middle (dapat malalim, this is the Corneal thickness = 3-4x) FUNDOSCOPY WITH SLIT LAMP 3 MIRROR GONIOSCOPIC LENS o TECHNIQUE Character of aperture: Moderate slit beam Typical magnification: 16-45x Angle of illumination: Coaxial (~10 o ) Filter: Neutral density 4 mirrors: 1 st : used to view angle; 2 nd : view surface of iris; 3 rd : view posterior of iris; 4 th : central mirror, view the retina CONTACT SLIT LAMP FUNDOSCOPY LENSE SLIT LAMP
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________________________________________________ OPHTHALMOLOGY _________________________________________________________________________________________________________________________________________________________________ Transcribers: PAGGAO | YALA Page 9 of 9 o TECHNIQUE Character of aperture: 2mm Typical magnification: 16-45x Angle of illumination: Coaxial (5-10o) Filter: Neutral density NON CONTACT SLIT LAMP FUNDOSCOPY LENSES o TECHNIQUE Character of aperture: Moderate (2mm) Typical magnification: 16-45x Angle of illumination: Coaxial (~10 o ) Filter: Neutral density
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________________________________________________ OPHTHALMOLOGY _________________________________________________________________________________________________________________________________________________________________ Transcribers: BUGAYONG | GELOSO Page 1 of 3 1.02C OBJECTIVE & SUBJECTIVE EXAMINATION OF THE EYE VISUAL ACUITY DR. MONDIGUING August 18, 2017 PRELIMS: QUIZ 1 Bold,red letters = Emphasized during lecture Italic, blue letters = Audio Green= OT VISUAL ACUITY first examination done in eye assessment most frequently done recorded as “VA” is a FRACTION: Test dstance Distance at which the smallest optotype identified subtends an angle of 5 minutes of an arc OPTOTYPES Optoptype refers to letters, numbers or images that are seen in a visual acuity chart Size of letters are all measure and scaled so when you measured them they are all 5 minutes of an arc Minute refers to measurement of an angle, smaller than a degree 1 minute = .0166 degree (you don’t need to memorize these) Basis for Constructing the Optotype - optotype that is at 20/200 means at 200 ft this is the size of a letter that subtends an angle of 5 degrees of an arc. - The letter only becomes bigger as the distance becomes farther. So if the patient is at 50 ft, the letter should be that big (refer to image) and at 100ft, it should be that big. The size of the optotype changes depending on the distance of the observer. VISUAL ACUITY: MEASUREMENT Normal visual acuity is 20/20 SNELLEN’S CHART – most commonly used, level of difficulty is different per row BAILEY – LOVIE CHART - level of difficulty is equal per row Measured in 2 ways: o Distance Vision o Near Vision We usually do distance vision first then near vision DISTANCE VISION Measured at a certain distance: 20ft or 6m with ample
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  • Spring '14
  • JulieA.Howe
  • o Cornea, Slit lamp

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