gas permeable problem solving n.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
GAS PERMEABLE PROBLEM SOLVING PowerPoint Presentation
Download Presentation
GAS PERMEABLE PROBLEM SOLVING

Loading in 2 Seconds...

play fullscreen
1 / 24

GAS PERMEABLE PROBLEM SOLVING - PowerPoint PPT Presentation


  • 122 Views
  • Uploaded on

GAS PERMEABLE PROBLEM SOLVING. GP PROBLEM SOLVING. Progress Evaluation Procedures Reduced Visual Acuity Decentration Reduced Surface Wettability Power Change Corneal Desiccation Refitting into GPs. GP PROBLEM-SOLVING. Progress Evaluation Procedures. PROGRESS EVALUATION PROCEDURES.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

GAS PERMEABLE PROBLEM SOLVING


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
gp problem solving
GP PROBLEM SOLVING
  • Progress Evaluation Procedures
  • Reduced Visual Acuity
  • Decentration
  • Reduced Surface Wettability
  • Power Change
  • Corneal Desiccation
  • Refitting into GPs
gp problem solving1
GP PROBLEM-SOLVING
  • Progress Evaluation Procedures
progress evaluation procedures
PROGRESS EVALUATION PROCEDURES
  • Lenses On:
    • Visual Acuity
    • Retinoscopy (OR)
    • Sphere-Cylinder
    • Biomicroscopy
      • Lag
      • Surface Quality
      • Edema
progress evaluation procedures1
PROGRESS EVALUATION PROCEDURES
  • Lenses Off
    • Biomicroscopy
      • Staining
      • Limbal Vasculature
      • Lids

Keratometry

Subjective

Verification

gp problem solving2
GP PROBLEM SOLVING
  • Progress Evaluation Procedures
  • Reduced Visual Acuity
reduced visual acuity
REDUCED VISUAL ACUITY
  • Flexure
  • Warpage
  • Decentration
  • Reduced Surface Wettability
  • Power Change
reduced visual acuity1
REDUCED VISUAL ACUITY
  • Flexure:
    • Bending of a flexible GP lens on a toric cornea
    • Diagnosed via over-K’s; if toric & radiuscope is spherical = flexure
    • Managed via flatter BCR, smaller OZD &/or increased center thickness
reduced visual acuity2
REDUCED VISUAL ACUITY
  • Flexure
  • Warpage:
    • Caused by excessive digital pressure, especially with high Dk material & digital cleaner
reduced visual acuity3
REDUCED VISUAL ACUITY
  • Flexure
  • Warpage
  • Decentration: Causes include:
    • Lens Design
    • Lens Material
    • Corneal Topography
    • Lid Tension/Blink Quality
reduced visual acuity decentration
REDUCED VISUAL ACUITY: DECENTRATION
  • Complications:
    • Reduced/Variable Vision & Flare
    • Limbal Irritation/ 3 & 9 staining
    • Lens Awareness
    • Lens Dislocation
    • Poor Corneal Alignment; excessive flattening & steepening with possibility of distortion
reduced visual acuity inferior decentration
REDUCED VISUAL ACUITY: INFERIOR DECENTRATION
  • Management:
    • Reduce Center Thickness
    • Proper Edge Design (- lent < -1.50D/+); +lent. > -5.00D
    • Bitoric > 2.50D corneal cyl
    • Lid Attachment Design
reduced visual acuity lateral decentration
REDUCED VISUAL ACUITY: LATERAL DECENTRATION
  • Causes: ATR Cyl./ displaced corneal apex
  • Management: Increase OAD or Steeper BCR; aspheric design
reduced visual acuity4
REDUCED VISUAL ACUITY
  • Flexure
  • Warpage
  • Decentration
  • Reduced Surface Wettability
  • Power Change
gp problem solving3
GP PROBLEM SOLVING
  • Progress Evaluation Procedures
  • Reduced Visual Acuity
  • Corneal Desiccation
gp problem solving corneal desiccation
GP PROBLEM-SOLVING: CORNEAL DESICCATION
  • Definition: Dryness or peripheral desiccation staining occurring in 3 & 9 o’clock regions of the cornea.
  • Occurs in over 50% of rigid lens wearers (but decreasing)
  • Ranges from diffuse punctate staining (most common) to corneal opacification & neovascularization
gp problem solving corneal desiccation1
GP PROBLEM SOLVING: CORNEAL DESICCATION
  • Diameter: larger reduces area; smaller reduces mass
  • Lens Position: Inferior least desirable (Henry, Bennett & Forrest, AJO, 1086)
  • 3 & 9 o’clock staining-to-fit relationship
    • Position #Eyes 3 & 9 %

Sup-Centr 125 48 38

Interpalp 193 111 57

Inf-Centr 46 34 73

corneal desiccation
CORNEAL DESICCATION
  • Edge Lift: Too small versus too large
  • Center Thickness: Problems of large CT: Verify!
  • Edge Shape: well polished, thin & tapered
gp problem solving4
GP PROBLEM SOLVING
  • Progress Evaluation Procedures
  • Reduced Visual Acuity
  • Corneal Desiccation
  • Refitting into GPs
refitting into gps
REFITTING INTO GPS
  • Complications
    • Edema (98%)
    • Corneal Warpage
    • Corneal Exhaustion
refitting into gps1
REFITTING INTO GPS
  • Possible Applications (keratoconus, high astigmatism, presbyopia, soft failures, orthokeratology)
  • Liability
    • Explain GP benefits (effects of PMMA wear, O2 permeability, modern technology, vision in spectacles)
    • Audiovisuals: photographs/slides, videotapes
refitting into gps2
REFITTING INTO GPS
  • Refitting Procedure
    • Immediate refit without loss in wearing time
    • If corneal warpage, reduce wear time to minimum they can wear and refit one week later
    • Same design or new design???
refitting into gps from soft lenses
REFITTING INTO GPS FROM SOFT LENSES
  • Most common reasons:
    • GPC
    • Poor Vision