Optometry Guidelines for Spectacle Dispensing

Guideline 2

• Refractive power -0.25DS to +0.75DS should not be prescribed for patients under 16 years old. + lenses are only for accommodation problems and oculomotor balance issues.
• Optometrists should help patients select frames and lenses meeting minimum requirements for spectacle prescriptions.
• Accurate measurements for frame and lens fitting are essential, considering lens height, fitting plane, and centration.
• Dispensing spectacles requires verifying prescriptions and records, along with eye examinations.
• Optometrists should provide advice on proper eye examinations before duplicating spectacles (6 months/1 year).
• Glass lenses should not be prescribed to children without explaining safety issues.

Guideline 3

• Optometrists edging ophthalmic lenses must consider parameters like optical centration and fitting heights.
• Optometrists with relevant equipment must maintain it in proper working order.
• Well-fitting frames provide comfort and effective vision correction.

Benefits of Well-Fitting Frames

• Comfort
• Effective vision correction

Steps in Standard Alignment or Truing of Frames

• (I. Bridge)*

• Check for horizontal alignment (skewed bridge).

• Check for vertical alignment (vertical plane of lenses).

• Check for X-ing (twisted bridge).

• (II. Endpiece)*

• Check temple alignment

• Check the temples for straightness of shaft

• Check for bent end piece and loose rivets

• Check for proper hinge bending

• (III. Earpiece)*

• Check the temple alignment (bent-down portion of the temple).

• Ensure equality of downward and inward bend.

• (IV. Temple Fold Angle)*

• Check for central crossing of the temple shafts when folded.

• Ensure correct fold for easy insertion into cases.

• Horizontal Alignment correction- heat the bridge and force one side up and the other down

• Vertical Alignment correction - heat the bridge and press on the side that is forward or backward

• X-ing (twisted bridge) correction - heat the bridge and move wrists oppositely when grasping the frame.

• Temple Alignment correction - heat the end piece, hold frame by lens/eyewire, push/pull end piece and bend to correct the 90-95 degrees angle

• Pantoscopic angle correction - adjust temple angle (degrees) by grasping it for upward or downward movement

Lens Treatment

• Keep spectacles in cases to prevent damage.
• Avoid high heat surfaces.
• Use mild hand soap to clean lenses.
• Use microfiber cloths to clean and shine lenses.

Lens Surfacing

• Conventional surfacing - standards molds for prescription lenses.
• Freeform surfacing - computer controlled surfacing equipment.
  • High definition, wider field, sharper image quality, and better peripheral vision

Sustainability

• Meeting current needs without compromising future generations' needs.

Recycling Materials for Frame Production

• Dresden Vision (Australia): recycled and recyclable materials.
• Proof Eyewear (US): sustainably sourced woods, biodegradable acetate, and recycled aluminum.
• Owndays (Japan): Castor plant.

Efforts by Manufacturers

• (1. Electricity)*
• Renewable energy (solar panels, green energy suppliers).
• Invest in energy efficient infrastructure (lighting, insulation, heating/cooling).
• (2. Water)*
• Dry-edging instead of wet-edging.
• Water recycling in manufacturing.
• (3. Plastic)*
• Reduce plastic use in lens manufacturing.
• (4. Others)*
• Reduce transportation (sea vs. air shipping).
• Recycle plastics, cardboard.
• Proper waste disposal

Lens Coating

• Light transmission reduction (light loss from reflection).
• Cosmetically unappealing.
• (Principle of Anti-Reflection Coating (AR Coating))*
• Path condition -2 waves exactly out of phase.
• Amplitude condition - 2waves equal in strength
• AR Coat Thickness= (λ/ 4n). λ= wavelength of light, n= refractive index of coating
• Refractive Index of AR Coat= √(nl). nl= Refractive Index of the lens
• Multi-coat Increases anti-reflection with higher index and flatter lenses.
• (Lens Coating)*
• Hard coat - scratch resistance.
• UV coating - enhances UV protection
• Anti-fog
  • Prevent condensation -Reduce surface tension -Durable and last -Temporary less expensive
• Polarizer -Reduce glare -Check via LCD screen -compare with polarized lenses

This quiz covers essential guidelines for optometrists regarding the prescription and dispensing of spectacles. It includes parameters for refractive power, frame selection, accurate measurements, and the importance of patient eye examinations. Test your knowledge on best practices in optometry.