Optometry Guidelines for Spectacle Dispensing

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What should be the refractive power limit for prescriptions given to patients under 16 years old?

-0.25DS to +0.75DS (correct)

-0.50DS to +0.50DS

-0.75DS to +1.00DS

0.00DS to +1.00DS

What is one of the key benefits of well-fitting frames?

Enhanced color perception

Reduction of eye strain

Increased fashion appeal

Effective vision correction (correct)

Which of the following should an optometrist NOT do before dispensing spectacles?

Verify the prescription

Adjust the frames for fashion (correct)

Review the ophthalmic record

Conduct an eye examination

What should be considered when edging ophthalmic lenses?

Key parameters of the lenses Signup and view all the answers

What corrective action should be taken if one lens is higher than the other?

Heat the bridge and adjust accordingly Signup and view all the answers

How often should a proper eye examination be advised before duplicating spectacles?

Every 6 months to 1 year Signup and view all the answers

What does a twisted bridge in spectacles indicate?

X-ing Signup and view all the answers

What should not be provided to children without explaining relevant safety issues?

Glass lenses Signup and view all the answers

What is the primary purpose of an anti-reflection coating on lenses?

To minimize reflections and improve clarity Signup and view all the answers

Which statement about the refractive index of an anti-reflection coating is correct?

It can be calculated from the equation $Refractive\ Index\ of\ AR\ Coat = \sqrt{nl}$. Signup and view all the answers

What is a characteristic of blue light coatings on lenses?

They may have a bluish reflecting coat that blocks 10% of blue light Signup and view all the answers

What treatment should be avoided to protect the lenses from damage?

Leaving them in high heat areas like BBQ pits Signup and view all the answers

Which advantage does Free Form lens surfacing technology provide?

Sharper image quality and better peripheral vision Signup and view all the answers

What is the typical range for correction of angle in eyewear adjustments?

90-95 degrees Signup and view all the answers

How should the pantoscopic angle be corrected if the temple is not parallel?

Close the temple a few degrees Signup and view all the answers

What is the correct approach to address asymmetrical downward and inward angle of drop in the temple?

Heat one side and pull out the bend Signup and view all the answers

Which method is used to correct the temple fold angle in eyewear?

Grasping with angling pliers at the hinge screw Signup and view all the answers

What is the typical vertex distance for eyewear adjustments?

12mm-15mm Signup and view all the answers

What defines sustainability in the context of ophthalmic lenses?

Meeting current needs without compromising future generations Signup and view all the answers

Which company is known for using recycled and recyclable materials in frame production?

Dresden Vision Signup and view all the answers

What is a primary effect of lens coating on eyewear wearers?

Reduces light transmission Signup and view all the answers

Study Notes

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

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

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.