PRESBYOPIA. PRESBYOPIA: PROGRAM Presbyopia: program Definition The start and influential factors...

PRESBYOPIA

PRESBYOPIA: PROGRAM

Presbyopia: program

• Definition• The start and influential factors• Symptoms and signs• Determination of the addition• Prescription• Resolution of clinical cases

PRESBYOPIA: DEFINITION

Presbyopia: definition

– Difficulty focusing on objects because of an insufficient amplitude of accomodation for working comfortably in NV, supposing a well compensated refractive defect from far.

– It is a normal physiological state due to the loss of the accomodative capacity with the passage of time.

– The NPA moves away and the habitual work distance remains outside of the zone of comfortable and clear vision

PRESBYOPIA: THE START AND INFLUENCING FACTORS

Presbyopia: factors I

• The age at which the presbyopia appears depends on:– The accomodative capacity of the person– The habitual work distance (near)– The visual demand at near distances– The refractive error– Nutritional and geographical factors

Presbyopia: factors II

• Accomodative capacity of the person– A method used to determine the amplitude

of accomodation– Intersubject variability– Accomodation in comfortable vision

Presbyopia: factors III

• Habitual, near work distance:– Habit and anthropometric characteristics– At the beginning a slight distancing of the

material allows for comfortable vision

Presbyopia: factors IV

• The visual demand at near distances:– Does not diminish the accomodative capacity– Can make the symptoms more severe.

Presbyopia: factors V

• Refractive error in DV:– Myopia / Hypermetropia– Use of glasses / Contact lenses

Presbyopia: factors VI

• Nutritional and geographical factors

PRESBYOPIA: SYMPTOMS AND SIGNS

Presbyopia: symptoms and signs I

• Symptoms:– Blurry vision in NV– Distancing the reading material– Ocular fatigue– Headaches– In principle it can include blurry vision in

DV (after working in NV)

Presbyopia: symptoms and signs II

• Signs:– Reduced amplitude of accomodation in order to

work comfortably at the habitual reading distance.

– The amplitude of accomodation is determined with the necessary refraction in DV and through any of these methods:• Methods (already seen)

DondersSheardHofstetter’s formula:

Average amp acc = 18,5 – age x 0,3

Presbyopia: symptoms and signs III

Examples: Averageexpected amp acc = 18,5 – age x 0,3Amo Acc

Average

Ano AccComfortab

le

16,5cm

-2 sc

50

15cm-4 sc

55

+4 cc

60

25cm-1 cc

45

ObservationsAmp AccReal

NPARxAge

Presbyopia: symptoms and signs III

Examples: Averageexpected amp acc = 18,5 – age x 0,3

3,50D

2,00D

0,50D

5,00D

Amp accAverage

2,00

1,33D

0,00D

2,00D

Amp accComfortab

le

Amp acc normal for the age.NoC can see between 16,5 and 50cm approx.

4,00D

16,5cm

-2 sc

50

Amp acc normal for the age.NoC can see between 15 and 25cm approx.

2,66D

15cm-4 sc

55

Amp acc normal for the age. Has absolute presbyopia

0,00D

+4 cc

60

Amp acc is normal for the age. Will have presbyopia if the habitual work distance is <50cm approx.

4,00D

25cm-1 cc

45

ObservationsAmp accReal

NPARxAge

PRESBYOPIA: DETERMINATION OF THE ADDITION

Presbyopia: determination of the addition I

• Trial method• Amplitude of accomodation method• Cross-cylinder (near) method• Bichromatic test method• Age method

Presbyopia: determination of the addition II

• Trial method– Patient with Rx in DV, test to 40 cm (or

habitual distance of NV) well lit– Mono and/or binocularly

• Cover LE and go on adding +0.25D in the RE until the patient sees clearly

• The same for LE• Refine the result adding 0.25D binocularly

Presbyopia: determination of the addition III

• Amplitude of Accomodation method– Takes into account that 1/2 the amplitude of

accomodation (amp acc) remains in reserve– With the adequate Rx for DV, determine the amp acc

through the push-up method – Apply the formula:

• Addition = 1/dt (m) - amp acc/2dt = work distance

– Example:• Amp acc=2D; dt= 33 cm• Ad=1/0,33 - 2/2= 2 D

Presbyopia: determination of the addition IV

• Cross-cylinder method from near:– Patient with Rx for DV– Dim lighting– Grid optotype at habitual distance in NV– Cross-cylinder with negative axis at 90°. Ask

which lines he/she sees more clearly:• We hope they are the horizontal lines• Add positive lenses until verticle and

horizontal lines are seen equally clearly

– Can be done monocularly or binocularly

Presbyopia: determination of the addition V

• Bichromatic method:– Patient with Rx for DV– Bichrome test at the habitual distance in NV– Ask on which background the patient sees the

letters more clearly• We hope it is the green background• Add positive spheres until he/she says “better on

the red background”• Reduce positives until he/she sees equally in both

eyes

– In case of doubt allow slightly better vision in the red background

Presbyopia: determination of the addition VI

• The age method:– Empirical method based on clinical

experience– Patient with Rx for DV– Reading test at a habitual distance in NV– There are approximated addition tables

depending on age– Refine the result adding 0.25D binocularly

Presbyopia: determination of the addition VI

• The age method:– The tables can vary according to geographical zone

AGE (years)

Addition at 40cm

Addition at 33cm

40 +0.25 D +1.00 D

45 +0.75 D +1.50 D

50 +1.25 D +2.00 D

55 +1.75 D +2.50 D

60 +2.00 D +3.00 D

65 +2.25 D

70 +2.50 D

Table proposed by Borish (1970)) Empirical table in Spain

AGE (years)

Addition at 40cm (approx)

40 - 45 +0,75 a +1,00 45 - 50 +1,00 a +1,75 50 - 55 +1,75 a +2,25

55 - 65 +2,50 > 65 +2.50 a +2,75

Presbyopia: determination of the addition VII

• All of the previous methods are approximate• It is essential to make necessary

adjustments with trial frames in a situation as similar to real life as possible

• Demonstrate the steps of the accomodation check

• Explain to the patient:– The need for distinct compensation in DV and NV– The expected evolution

PRESBYOPIA: PRESCRIPTION

Presbyopia: prescription I

• It is important to determine the best form of compensation for the person’s visual needs:– Monofocal in NV– Bifocal– Progressives– Occupational lenses

Presbyopia: prescription criteria I

• Monofocal lenses– Useful for static, long-term tasks– The glasses should be taken off to see from

distances

• Bifocal lenses– For NV and DV – Inform about image jump and displacement

• Progressive lenses– For DV, NV and intermediate distances– There are peripheral areas with optical aberrations– Very precise adaptation

PRESBYOPIA: CASES

Presbyopia: case 1-I

• JAR, 46-year-old woman. High school teacher.

• MC: Difficulty focusing on text in NV. Best vision when she distances the text. In DV she says she sees well with her glasses.

• PH: Has worn glasses since the age of 9. No significant changes in the last 20 years. No illnesses or ingestion of medication.

• FH: Unimportant.

Presbyopia: case 1-II

• Habitual Rx and AV in DV and NV:– RE: -4,50; 20/20; NV: 20/30– LE: -5,00; 20/20; NV: 20/30-2

• Binocularity in habitual conditions:– Cover test:

• DV: Ortho• NV: Low exophoria

– Proximal convergence: 5/10cm

Presbyopia: case 1-III

• Retinoscopy:– RE: -4,50– LE: -5,00

• Subjective DV and AV:– RE: -4,50; AV: 20/20– LE: -5,00; AV: 20/20

• Addition in NV: +1,00; AV 20/20 in both eyes. Good comfort.– Vision check: from 20 to 60cm approximately

• Ocular health exams: within normal limits

Presbyopia: case 1-IV

• Complete diagnosis of the case• Proposed treatment and plan of

revisions• Possible evolution of the condition

Presbyopia: case 1-V

• Complete diagnosis of the case– Simple myopia in both eyes– Presbyopia– Binocularity: within normal limits– Other tests are within normal limits

Presbyopia: case 1-VI

• Proposed treatment:– A change to the prescription in DV is not justified.– An addition in NV of +1,00D is necessary.– After discussing the possible options, a monofocal for

NV is decided upon:• RE: -3,50• LE: -4,00

– Use for tasks in NV. – Show the patient that with them the vision in DV is

inadequate.– Revision in 1½-2 or before if there are symptoms.– Explain the condition to the patient.

Presbyopia: case 1-VIII

• Possible evolution of the condition:– Stability of the refractive defect in DV– Need for a new graduation for NV in about 2

years due to increase in the presbyopia.

Presbyopia: case 2-I

• MPA, 52-year-old male. Taxi driver.• MC: When he wants to read for a while

he notices blurry vision in NV even with his glasses. Greater difficulty in low lighting.

• PH: Wears bifocals when working and for NV since he was 6 or 7. No illnesses or ingestion of medication.

• FH: Irrelevant.

Presbyopia: case 2-II

• Habitual Rx and AV in DV and NV:– RE: +0,50; AV:20/25; NV: +1,75; AV: 20/30-2

– LE: +0,50; AV:20/25; NV: +1,75; AV: 20/40

• Binocularity in habitual conditions:– Cover test:

• DV: Ortho• NV: Ortho

– Proximal convergence: 10/15cm

Presbyopia: case 2-III

• Retinoscopy:– RE: +1,50-0,50x180º– LE: +1,75-0,25x180º

• Subjective DV and AV:– RE: +1,50-0,50x180º; AV: 20/20– LE: +1,75-0,25x180º; AV: 20/20

• Addition in NV: +1,75; AV 20/20 in both eyes. Habitual work distance: 45cm– Vision check: from 30 to 55cm approximately

• Ocular health exams: within normal limits

Presbyopia: case 2-IV

• Complete diagnosis of the case• Proposed treatment and plan of

revisions• Possible evolution of the condition

Presbyopia: case 2-V

• Complete diagnosis of the case– Low hypermetropis manifested in both eyes– Low, direct astigmatism in both eyes– Presbyopia– Binocularity: within normal limits– Other tests within normal limits

Presbyopia: case 2-VI

• Proposed treatment:– After discussing the possible options,

progressives have been decided upon:• RE: +1,50-0,50x180º; Ad: +1,75• LE: +1,75-0,25x180º; Ad: +1,75

– Habitual use. – Revision within 1½-2 years or before if

symptoms reappear.– Explain the condition to the patient.

Presbyopia: case 2-VIII

• Possible evolution of the condition:– Stability of the refractive defect in VA– Need for a new graduation for NV in a few

years due to slight increase in the presbyopia.

PRESBYOPIA: BIBLIOGRAPHY

Presbyopia: Bibliography

• Amos JF. Diagnosis and management in vision care. Butterworth-Heinemann, 1987

• Milder B, Rubin ML. The fine art of prescribing glasses (2nd edition). Triad Publishing company, 1991

• Brookman KE. Refractive management of ametropia. Butterworth-Heinemann, 1996

• Werner DL, Press LJ. Clinical pearls in refractive care. Butterworth-Heinemann, 2002

• Eskridge JB, Amos JF, Barlett JD. Clinical procedures in optometry. Lippincott Co, 1991.

Presbyopia: web pages

• http://www.emedicine.com/oph/topic724.htm• http://www.emedicine.com/oph/topic699.htm• http://www.tarso.com/Presbyopia.html• http://www.nlm.nih.gov/medlineplus/spanish/

ency/article/001026.htm• http://www.agingeye.net/otheragingeye/

presbyopia.php• http://en.wikipedia.org/wiki/Presbyopia• http://www.eyetopics.com/articles/48/1/

Presbyopia