Presbyopia/ Methods of Presbyopic Addition Determination (healthkura.com)

Presbyopia and Techniques of Measurement
Bikash Sapkota
B. Optometry
3rd year
Maharajgunj Medical
Campus, Nepal

LAYOUT
o Introduction
o Types of presbyopia
o Risk factors
o Symptoms and signs
o Refractive error and presbyopia
o Methods of determining near add.
o Management of presbyopia

o Presbyopia (from Greek presbys = old man
+ ops = see like, sight)
o Gradual, irreversible decrease in amplitude of
accommodation as expected with age
o Normal physiological state
Definition

o Eye exhibits a progressively diminished ability to
focus on near objects
o The onset is usually anticipated by age 40 or AA
tends to drop below 5.00D
o Eye crystalline lens loses elasticity (the ageing of a
lens)
o Old aged eye (आँखा बुढो भयो)
Definition

Amplitude of Accommodation
and Age
The amplitude of accommodation declines throughout life
until at about 50 or 60 years of age when it becomes zero

Recession of near point with age

Accommodation Insufficiency
& Presbyopia
AI PRESBYOPIA
Accommodative power is
significantly less than the
normal physiological limit for
the patient’s age
Physiological insufficiency of
accommodation is normal
for age
Asthenopic symptoms are
more prominent
Symptoms of decreased
near VA is more prominent

Epidemiology
oWorldwide in 2005 over 1.04 billion
oBy the year 2020 the worldwide prevalence is expected
to rise to 1.37 billion
oThe average age of onset-betn 42 and 44 years of age
oEarly loss of accommodative ability can be induced by
certain systemic disease, medications, and trauma
-Holden BA, Fricke TR, Ho SM, Wong R, Schlenther G, Cronjé S, Burnett A, Papas E, Naidoo KS,
Frick KD. Global vision impairment due to uncorrected presbyopia. Arch Ophthalmol. 2008
Dec;126(12):1731-9.

Pathophysiology
Lenticular and extra-lenticular theories
• Lenticular
 sclerosis of the nuclear lens tissue
 decreased distance between ciliary muscle and lens
equator
 lens capsule with age becomes thicker, less extensible
and brittle

• Extra-lenticular
 age related hyalinization of ciliary processes and ciliary
muscles
 loss of elasticity in the zonules
 decreasing resistance of the vitreous humor against the
accommodating lens capsule

Some of the Theories
Theories
Helmholtz
Schachar
Catenary

In Presbyopia
Ciliary muscle contraction ceases
Posterior zonular fibres pull the ciliary
muscle backward
Increases tension on the zonular fibres
Increase in lens diameter, decrease in
lens thickness and a flattening of the
anterior and posterior lens surface
curvatures
Decrease in optical power
Helmholtz theory

Schachar’s Theory
Ciliary muscle contracts
Equatorial zonular tension is
increased
Anterior and posterior zonules
are simultaneously relaxed
Central surfaces of the lens
steepen
Peripheral surfaces of the lens
flatten

oPresbyopia results from growth of equatorial diameter
of the lens
oWith age, the perilenticular space is reduced and ciliary
muscle contraction no longer tense the zonules and
expand coronally
oBased on this theory introduced new sx for presbyopia
scleral expansion bands

Catenary Theory
oProposed by Coleman
oThe zonular fibers function like the support pylons of a
suspension bridge and determine the natural curvature
of the lens

Ciliary muscle contracts
Initiates a pressure gradient between
the vitreous and aqueous
compartments
Anterior capsule and the zonule form
a trampoline shape or hammock
shaped surface
Steep radius of curvature in the center
of the lens with slight flattening of the
peripheral anterior lens
Presbyopia occurs d/t
- increase lens volume with
age
- results in a reduced
response of anterior
radius of curvature to the
vitreous pressure gradient
created by ciliary body
contarction

Types of Presbyopia
PresbyopiaFunctional
Incipient
Premature Nocturnal
Manifest
Absolute

oBorderline, beginning, early or pre-presbyopia
oEarliest stage when symptoms or difficulty are first
encountered in near vision
oMore difficulty in dim illumination while can do well in
bright illumination
Incipient Presbyopia

oPt.’s history suggests a need for a reading add., but pt.
performs well visually on testing and, given the choice,
may prefer to remain uncorrected
Incipient Presbyopia

o When faced with gradually declining AA and continued
near task demands, adult pts. eventually report visual
difficulties
o The interaction between the pt.'s AA and the patient's
near vision demands is critical
Functional Presbyopia

o The age at which presbyopia becomes symptomatic
varies
o Due to variations in distance vision status, environment,
task requirements, nutrition, or disease state
Functional Presbyopia

oPresbyopia occuring at an earlier age than expected
for normal population
oUsually associated with ocular diseases, nutritional
deficiencies or ingestion of certain drugs
oUncorrected hyperopia
oPremature sclerosis of crystalline lens
Premature Presbyopia

oNear vision difficulties result from an apparent
decrease in the AA in dim light
oIncreased pupil size and decreased depth of field are
usually responsible for this reduction in the range of
clear near vision in dim light
Nocturnal Presbyopia

Manifest presbyopia
oPresbyopia with some amplitude of accommodation
present
Absolute presbyopia
oPresbyopia with amplitude of accommodation
completely absent

Risk Factors
o Age
Typically affects function at or after age 40
o Hyperopia
Additional accommodative demand (if uncorrected)
o Occupation
Near vision demands
o Gender
Earlier onset in females (short stature, menopause)

Risk Factors
o Ocular disease or trauma
Removal or damage to lens, zonules, or ciliary muscle
o Systemic disease
Diabetes mellitus; multiple sclerosis; cardiovascular
accidents; vascular insufficiency; myasthenia gravis;
anemia; influenza; measles
o Drugs
e.g., alcohol, chlorpromazine, hydrochlorothiazide,
antianxiety agents, antidepressants, antipsychotics,
antispasmodics, antihistamines, diuretics

o Iatrogenic factors
Scatter (panretinal) laser photocoagulation; intraocular
surgery
o Geographic factors
Proximity to the equator (higher average annual
temperatures, greater exposure to ultraviolet radiation)
o Other
Poor nutrition; decompression sickness; ambient
temperature
Risk Factors

“My arms are not long enough to see up close anymore”
"I have to hold my book further away"
“Newspaper print is not what it used to be"
Symptoms and Signs

o Blurred vision and the inability to see fine details at the
customary near working distance
o Other common symptoms are delays in focusing at near or
distance, ocular discomfort, headache, aesthenopia, neck &
back ache, redness & watering, fatigue or drowsiness from
near work, increased working distance, need for brighter
light for reading, squinting & diplopia
SIGNS Reduced amplitude of accommodation
Symptoms and Signs

Distance Intermediate Near
The vision with Presbyopia

Basic Principles
oFind refractive error for distance and correct it first
oFind presbyopic correction needed in each eye separately
and add it to distance correction
oNear point should be taken consideration according to
profession of pt.

Basic Principles
oOver correction should be avoided
oAdditional correction for intermediate distance may be
required
oPresbyopic add should leave certain percentage of AA in
reserve

AA in Reserve
oAmount of a new addition should permit a certain
percentage of the AA to remain in reserve
oRule-of-thumb
- Leaving one-half of the AA in reserve
(Lawrence and Maxwell)
- Leaving one-third of the AA in reserve
(Sheard and Giles)

Presbyopia correction and the
accommodation in reserve
o A small decline in the AA up to the age of 52
o After the age of 52 the results are based on the depth-of-focus
of the eye
o Females have slightly greater accommodation than males of
the same age
o The power of the add. correlates to the age of the subject
o Common figures of AA in reserve adopted have been one-half
and one-third (no strict rule)
- by Michel Millodot and Susan Millodot, 2007: Ophthalmic and Physiological
Optics, Volume 9, Issue 2

Methods of
Determining Near Add
o Addition based on amplitude of accommodation
o Tentative addition based on age
o Plus build-up method
o Bichrome method
o Cross-cylinder method
o Relative accommodation method
o Dynamic Retinoscopy

Tentative add based on
oAmplitude of accommodation decreases with age
- Presbyopia is reported when NPA exceeds 8 inches
(22cm) i.e, AA = 4.50D (Donders)
oPresbyopia exists when amplitude of accommodation is
less than 5D (Morgan)

oMeasured by the push-up method or the minus lens to
blur method
oFor older persons, AA can be measured with the pt.’s
addition
oThe amount of the add is then subtracted from the result
of the test

oAmount of a new add. should permit a certain percentage
of the AA to remain in reserve

oWorking distance (WD)= 40cm
RAF (AA) = 2.00D
What should be the near addition
Accommodation required for WD = 2.50 D
Accommodation in Reserve = 1.00D
Amount of accommodation left = 1.00D
Amount of Near addition = (2.50 –1.00)
= +1.50D
Example 1

Example 2
oWorking distance (WD)= 25cm
RAF (AA) = 1.50D
What should be the near addition
Accommodation required for WD = 4.00 D
Accommodation in Reserve = 0.50D
Amount of accommodation left = 1.00D
Amount of Near addition = (4.00 –1.00)
= +3.00D

Tentative
Addition based on Age
o Amplitude of accommodation to age (Hofstetter)
• Maximum = 25.0 – 0.4 (age)
• Probable = 18.5 – 0.3 (age)
• Minimum = 15.0 – 0.25 (age)
• Amount of near add calculated by holding certain
amount of accommodation in reserve
Rule of 4’s
Amplitude= 4x4-(Age/4)

Hofstetter’s
Table of Age and Amplitude
Age of Range (Years) Minimum Expected
Amplitude (Diopter)
Range of Near Add in
Diopter for 40 cm.
40 to 44 5.00 to 4.00 +0.75 to +1.00
45 to 49 3.75 to 2.75 +1.00 to +1.50
50 to 54 2.50 to 1.50 +1.50 to +2.00
55 to 59 1.25 to 0.25 +2.00 to +2.25
60 and over 0 +2.25 to +2.50

Plus build-up Method
oWorks best when the corrected VA is normal at distance
oCan be done binocularly or monocularly
 Plus lenses are increased in steps of 0.25D to the
amount necessary to first read the desired letters at
a customary working distance
 The power of add is then increased in 0.25D steps
to the amount preferred by the pt.

o Monocular build-up usually lands in more amount of
near addition
Since less accommodation
is available because of a
lack of convergence
accommodation
Plus build-up Method

Bichrome Method
oBased on natural chromatic aberration of eye
oWidely used for determining spherical component of
distant correction
oWhen an ametropic eye is out of
focus for distance,
- red target is clearer in myopia
- green target in hyperopia
oThe same principles apply at near distance

o For presbyopic pts. red & green are focused behind the
retina with red farther away
o For Uncorrected or undercorrected presbyopic pt.
- letters on green background clearer
o An overcorrection for a near target
- the letters on red background clearer
Bichrome Method

Appropriate
correction
Over corrected
Uncorrected or
under corrected
Bichrome Method

o Pt.’s distance correction is placed on a trial frame
o Bichrome target is placed at habitual near distance (40cm)
o Tell the pt. to look at letters on both Green and red
background carefully
o Ask the pt. which side has the sharper and clearer letters
- Green clear : add plus in 0.25 step
- red clear : remove plus
- until pt. sees letters equally clear in both background
Bichrome Method

o With the older patients,
- the crystalline lens becomes markedly yellow
- blue green light being partially absorbed and scattered
- gives a red bias to the test
o Difficult in protanopic patient; since the red background
will appear much dimmer than the green
o Precaution : the subject is instructed to emphasize on
clarity of letters and not the background
Demerits of Bichrome test
Bichrome Method

The Cross Cylinder
Method
o Used to establish the point of accommodation for a
customary near WD (40 cm), adding plus lenses until the
horizontal and vertical lines on the cross cylinder grid
subjectively appeared equally clear
o The target consists of 4 to 5 vertical and horizontal lines
presented to pt. at 40 cm
o Illumination is diffuse and subdue, sufficient to allow pt. to
see target satisfactorily

The Cross Cylinder
Method
+0.50DC -0.50DC +0.50DS/-1.00DCꭓ180

o Place the pt.’s best distance correction on the phoropter
(trial frame)
o Put the cross cylinder grid at pt.’s customary near working
distance (40cm)
o Place the Jackson Cross Cylinder in front of both of the pt.’s
eyes, with the minus cylinder axis at 900 (Red marks vertical)
(+0.50DS/-1.00DC ꭓ 090)
(be cautious not to change the axis of the correcting cylinder)
The Cross Cylinder
Method

o Cross cylinder creates artificial astigmatism with an
interval of Sturm of 1.00D
o If pt. accommodates exactly for the target, both sets of
lines are equally clear
o If pt. under-accommodates, the horizontal lines appear
clear
o Can be done monocularly or binocularly
The Cross Cylinder
Method

Two variations of technique
With Myopisation
Without
Myopisation
The Cross Cylinder
Method

The Cross Cylinder
Method
o A +3.00 D lens is added binocularly to the distance
correction of pt. such that the individual can see the
vertical lines more sharply
o The add is then decreased binocularly in 0.25 D steps until
both the vertical and horizontal lines appeared equally
clear
With Myopisation

The Cross Cylinder
Method
o With the distance correction placed in the phoropter, pt. is
asked which lines appear clearer, sharper or blacker
o If the horizontal lines are clearer, plus lenses are added
binocularly in 0.25 D steps until equality is reached
o Power of the plus lenses added is the tentative add
o In pt. initially appreciate the vertical lines or both more
clearly, the addition is recorded as zero
Without Myopisation

Relative Accommodation
Method
o NRA - measure of maximum ability to relax
accommodation while maintaining clear, single binocular
vision of a test object at a specified distance
o PRA - measure of the maximum ability to accommodate
while maintaining clear, single binocular vision of a target
at a specified distance
o The difference between the NRA and the PRA is called the
relative accommodative amplitude

Method
o Based on the concept of placing the accommodative
demand in the middle of the range of relative
accommodation
o To measure NRA and PRA,
- pt.'s distance refraction and a tentative add is placed
in the phoropter (Trial frame)
- the near point test card (N6 target) is placed at the
reading distance (usually 40 cm)

Method
o NRA is determined by adding plus power lenses binocularly
until the pt. is no longer able to read the fine print on the
test card
o PRA is determined by adding minus power lenses until the
pt. is no longer able to read the fine print
o Near add = (NRA+PRA)/2

Example
oSuppose pt. can read fine print with +1.00D add
oBlurring occurs when add increased to +2.00D and
reduced to +0.50D
oRange of clear vision is 1.50D (from +2.00D to +0.50D
add)
oFinal add is (+0.50+2.0)/2= +1.25D

Dynamic Retinoscopy
o Determine lag of accommodation
o Reduce amount of lag by +0.50 to +0.75D
o Prescribe remaining as addition for near

Comparing methods of determining
addition in presbyopes
o All the techniques display similar behavior and provide a
tentative addition close to the final addition
o Among the methods used, the age-expected procedure is
recommended, as this technique produce results that
correlate best with the final add
o Likelihood of error is high and supports the idea that any
tentative add has to be adjusted according to the particular
needs of each pt.
- CLINICAL AND EXPERIMENTAL OPTOMETRY 2008; B. Antona, F. Barra, A. Barrio, A. Gutierrez, E.
Piedrahita, Y. Martin Department of Optics II, Universidad Complutense, Madrid, Spain

An evaluation of estimation methods for
determining addition in presbyopes
o All the methods used display similar behavior and provide a
tentative addition close to the final addition
o Every tentative addition should be adjusted according to the
particular needs of the patient
- Arq Bras Oftalmol. 2013;76(4):218-20 by L.C. Bittencourt, M.R. Alves,
D.O. Dantas, P.F. Rodrigues, E.D. Santos-Neto

Determination of Final
Addition
o Customary near working distance
o Nature of the near work
o Physical nature of the patient
o Illumination level
o Status of the accommodation-convergence relationship
o Change in the amount of the addition

Refractive Error and
Presbyopia
HYPEROPES
EMMETROPES
MYOPES

Hypermetrope - presbyope
oHyperopes have their near point considerably further
away than emmetropes (exhibit apparent relatively
reduced accommodative amplitudes)
oThus effectively become presbyopic a few years earlier
than either myopes or emmetropes
oStronger converging lenses

Myope - presbyope
oIn the myopes develop presbyopia later in life
oBetter to take off distance prescription glasses for
reading (near task)
oWeaker converging lenses

Anisometropic distance
correction - Presbyopia
o Unequal adds may also be prescribed
o Measure the ranges monocularly
o Bifocals may produce reading discomfort because of an
induced vertical prismatic effect in the reading position
o Specially designed slab-off lenses or single vision reading
glasses may be required
(Ophthalmology by Myron Yanoff and Jay s. Duker)

Contact Lenses Spectacles
Surgery
Management of Presbyopia

o A variety of options are available
o Recommendations are made on the basis of the pt.'s
specific vocational and avocational needs
o Success of treatment depends on
- the lens power
- the specific visual tasks and characteristics of the
individual pt.
- the appropriate pt. education given by the practitioner

Optical Correction with Spectacle Lenses
o Single vision lenses
o Bifocal lenses
o Trifocal lenses
o Progressive addition lenses
o Occupational lenses

Optical Correction with Contact Lenses
o Single vision contact lenses
o Bifocal and multifocal contact lenses
- Alternating vision bifocal contact lenses
- Simultaneous vision contact lenses
o Monovision contact lenses
o Modified monovision contact lenses

Combination of Contact and Spectacle Lenses
o Many contact lens wearers gain some advantage by
combining the use of spectacles with their contact lenses
o Early presbyope who is already a contact lens wearer
continues to use their contact lenses for distance vision and
acquires a pair of reading spectacles for near, an approach
that has been shown to cause the least visual confusion at
near
(Sidock et al., 2000)

Surgical Treatment
oLaser in-situ keratomileusis (LASIK)
oMultifocal intraocular lens (IOL)
oAccommodating intraocular lens implants
oConductive keratoplasty (monovision)
oScleral expansion

In a nutshell..
o The evaluation and management of presbyopia are
important because significant functional deficits can
occur when the condition is left untreated
o Undercorrected or uncorrected presbyopia can cause
significant visual disability and have a negative impact
on the pt.'s quality of life
o Finally, every tentative addition should be adjusted
according to the particular needs of the patient

For Further
Reading
o Clinical Procedures in Optometry by J.D. Bartlett, J.B.
Eskridge, J.F. Amos
o Primary Care Optometry by Theodere Grosvenor
o Borish’s Clinical Refraction by W.J. Benjamin
o Clinical Procedures for Ocular examination by Carlson et al
o American Academy of Ophthalmology
o Optometric Clinical Practice Guideline by American
Optometric Association
o Internet

Presbyopia/ Methods of Presbyopic Addition Determination (healthkura.com)

Presbyopia/ Methods of Presbyopic Addition Determination (healthkura.com)

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