Glass prescription among youngs and educate elderly about

GLASS PRESCRIPTION AMONG YOUNGS AND EDUCATE ELDERLY ABOUT PROGRESSIVE LENSESDR. AMARENDRA KUMARM.S

WHY WE PRESCRIBE GLASSES Majority of patients in our opd comes with complaints of

VISUAL SYMPTOMS

OCULAR SYMPTOMS

REFFERED SYMPTOMS

• BLURRED VISSION• DIPLOPIA• CONFUSION

• HEADACHE

• ASTHENOPIA• EYE STRAIN• OCULAR IRRITATION• PAIN• In child intractable

blepharitis and conjunctivitis

GLASS PRESCRIPTIONHYPEROPIA Age Fogging Refinement methods1. Less than 3yrs ------- Full Correction2. 3 to 8yrs -------------- depends on tropia or phoria3. Adults to follow rule of strongest+ MYOPIA1. Thumb rules

Full Gross Value

subjective to AC/A

Full net--- optimal,

undercorrection

Normal Patients• -1to -6 full

correction• >-6 undercorrect

Esotropia• -6 DS or Above

under correct to optimal

Exotropia• Over correct

in intmittent Exotropia

GLASS PRESCRIPTION ASTIGMATISM

Normal Patients: In child less than 3 yrs of age = 1.25DS regular: Older than 3 yrs. = all astigmatism should be corrected Child and young : followed up 6 monthly Adults : 6 month to yearly Frequent changes : over correct (0.25D) Every patients suspected of refractive error should be checkeked Dry

and Wet AR For >5yrs Tropicacyl Plus every 10 min upto 30 min AR rechecked after

40 to 60 min For 3-5 yrs Atropine sulphate ointment tds for 3days AR rechecked

after 3days Cyclopentolate may be other option in little childs

RELATIONSHIP BETWEEN VISUAL ACUITY AND REFRACTIVE ERRORSnellens Visual

AcuityUncorrected Spherical Errors(DS)

Uncorrected Cylindrical Error(DC)

6/6 <=0.25 <=0.25

6/9 0.50 1.0

6/12 0.75 1.5

6/18 1.0 2.0

6/24 1.5 3.0

6/36 2.0 4.0

6/60 2.0-3.0 >=5.0

SOME COMMON DIFFERENCES BETWEEN ADULTS AND CHILDRENCHILDREN < 5YRS ADULTS

* Give refraction on axis as refracted

* Give cyl close to 90 or 180 degree

* Full hyperopic cycloplegic refraction tolerated well if less than age 5yrs

* Maximum tolerated plus even in refractive accommodative esotropia

* Subjective manifest refraction less important

* Subjective manifest refraction important

SOME COMMON DIFFERENCES BETWEEN ADULTS AND CHILDRENCHILDREN < 5YRS ADULTS

* Tolerate anisometropia; give full regardless of age, strabismus, amblyopia

* Tolerate anisometropia poorly

* < 12yrs non wearing or wearing wrong prescription will affect eye health

* Non wearing or wearing wrong prescription have only minor temporary consequences

# amblyopia, deviation, loss binocularity

# asthenopia, red eye, dry eye

SOME COMMON DIFFERENCES BETWEEN ADULTS AND CHILDRENCHILDREN < 5YRS ADULTS

* Tolerate aneisokonia better but also considered an implement to fusion and has amblyopia potential

* Tolerate aneisokonia poorly

* Anisometric Rx, Aneisokonic spectacle Rx has a role especially in patients requiring occlusion

* Will not wear Rx that has a large difference in refraction between the 2 eyes(threshold ? Different from patient to patient)

SOME EXAMPLES We prescribe Spherical power on the basis of Wet AR Cylindrical power on the basis of dry AR For AR under TP we reduce 0.75

3yrs old boy with dry AR RE +5.0 DS +1.0 DC@142 LE +6.0 DS+ 0.75 DC@71

wet AR RE +4.75 DS + 0.75 DC@152 LE +6.25 DS + 0.50 DC@69

Patient with phoria

Prescribed glass RE +4.0 DS +0.5 DC@140LE +5.0DS +0.25DC @ 70

5Yrs Boy with Amblyopia Dry ARRE +0.25 DS + 0.50DC @137 v 6/6LE +5.25DS + 0.75DC @54 v 6/36

Prescribed Glass

RE Plane v 6/6LE +3.50DS v 6/18 with proper

occlusion and followup

CONTD. High refractive errors

12 Yrs old girl with dry AR RE -5.25 DS -0.25 DC@37 v 3/60LE -4.75DS -1.50 DC@157 v 3/60

Wet AR RE -5.0DS -0.50DC@38 LE -4.25DS -1.50DC@151

Prescribed glassRE -4.75 DS v 6/6

LE -4.50DS -0.50DC @160 v 6/9

18yrs old boy with dry ARRE -0.25DS -4.75 DC@6 v 3/60LE -0.50DS -4.0DC@177 v3/60

Wet AR RE +0.25DS -4.75DC@4 LE +0.25DS-4.0DC@177

Prescribed glassRE -3.75 DC@5 v 6/9LE -3.25DC@180v 6/9

CONTD. Small errors with eye strain

15 yrs boy with Dry ARRE +1.0 DS +0.25 DC@88 v 6/6p

LE +1.25 DS +0.50 DC@104 v 6/6 pWet AR RE +3.5DS +0.75DC@70

LE +3.25DS +0.50DC@100Prescribed glass

RE +2.0DS V 6/6+1.75DS v 6/6p

(Full +latent Hyper )

19yrs girl with Dry ARRE -0.75 DC@87 v 6/6 pLE -0.75DC@92 v 6/6p

Wet AR RE +0.75 DC@177LE +0.75 DC@184

Prescribed glassRE -0.50DC@90 v 6/6LE -0.50 DC@90 v 6/6

(transposition)20 yrs boy with Dry AR

RE +0.50DS +0.50DC@93 v 6/9

LE +0.5 DS+0.75DC@95 v6/9p

Wet AR RE +1.5DS +0.50 DC@88 LE +1.50DS

+0.75DC@93Prescribed glass

RE +0.75DS +0.50DC@90 v

6/6LE +0.75 DS +0.75DC@90 v

6/6

PROGRESSIVE ADDITION LENSES When the near point has receded beyond the distance at which the individual is

accustomed to read or to work is known as presbyopia in Latin old man’s eyes. Decrease in amplitude of accommodation with age Increase in near point of accommodation with age Progressive spectacle lenses, also called progressive addition

lenses (PAL),progressive power lenses, graduated prescription lenses, and varifocal or multifocal lenses, are corrective lenses used in eyeglasses to correct presbyopia and other disorders of accommodation.

Progressive lenses more closely mimic the natural vision that you enjoyed before the onset of presbyopia. Instead of providing just two lens powers like bifocals (or three, like trifocals), progressive lenses are true "multifocal" lenses that provide a smooth, seamless progression of many lens powers for clear vision across the room, up close and at all distances in between.

Age in yrs Distance in cm Amplitude of accommodation(D)

10 7 1420 10 1030 14 740 20 350 40 2

PROGRESSIVE LENS (NO-LINE BIFOCAL)VS.LINE BIFOCAL Advantages No sudden “image jump” from distance to near. An infinite number of focal points to view objects at different distances. No visible line where the bifocal power begins. More natural vision for near viewing. A variety of lens designs to fit virtually any application. Disadvantages Requires a short period of adaptation to progressive lens for first-time wearers. Peripheral Distortion: Progressive lenses suffer the disadvantage of the power

progression creating regions of astigmatic aberration away from the optic axis, yielding poor visual resolution.

Costs more than a regular bifocal.

CONTD. Useful for long Computer user also protect from computer vision

syndrome Can be prescribe comfortably to myopic with presbiopia Better lens materials. Today's progressive lenses are available in

all the latest lens materials, making them thinner, lighter and more comfortable than ever before. Progressives made of high-index plastic lens materials can be up to 50 percent thinner than standard plastic bifocals.

Today, many progressive lenses have compact designs specially made for smaller eyeglass frames. With these new designs, wearers with small faces or anyone who wants a smaller, fashionable frame can enjoy all the benefits of progressive lenses.