Ill-sustained accommodation
WHAT?
-AKA accommodative fatigue
-Amplitude of accommodation is initially normal, but deteriorates over time after prolong focusing at near task.
-Sub-classification of accommodative insufficiency.
-An early stage of accommodative insuffciency.
CLINICAL SIGNS:
-Hard on any clinical tests that require stimulation of accommodation (hard on minus lens) and deteriorates AA over time.
MANAGEMENT:
1. Correction
2. Added plus lenses
3. Visual therapy
3. Description
WHAT?:
A condition in which the AA is normal under
typical test conditions, but deteriorates over time
with repeated accommodative stimulation.
If ill-sustained acc. is suspected, important to
repeat AA test several times.
AKA accommodative fatigue.
Sub-classification of accommodative
insufficiency.
An early stage of accommodative insufficiency
(Duane and Duke-Elder & Abrams).
4. Characteristics-Symptoms
Symptoms (~ Accommodative Insufficiency)
Blurred at near vision after prolong work
Discomfort and eyestrain associated with near
task
Fatigue & sleepiness associated with near point
tasks
Difficulty with attention and concentration when
reading
WHY?:
The accommodative system fails to sustain long-
term accommodative effort
5. Characteristics
Signs (Hard on clinical tests that require stimulation of accommodation):
AA:
Decreased if repeated 5-10 times;
Normal if administered once only.
PRA: Low /reduced
Acc. Facility test:
Fail –ve lens (monocularly or binocularly)
Performance decreases over time
Esophoria at near
MEM: High (>+0.75DS)
Fused cross cylinder: High
6. Distance
Near
•Ill-sustained accommodation is similar to accommodative
insufficiency except print may initially appear clear and easy to read
without effort.
• With time, the task at near begins to require more effort to focus.
•Blurred vision, eyestrain and headaches can occur with sustained
effort.
7. Etiology
1. Stage of convalescence from
debilitating(weakening) illness
2. Stage of generalized tiredness general
muscle fatigue
3. Uncorrected refractive error especially
hyperopia or astigmatism
4. Small difference of anisometropia between 2
eyes
8. Management & Care Process
3 options for management:
1. Correction of ametropia
Uncorrected rx can cause acc. Fatigue.
Small degrees of ametropia may significant to prescribe.
Can be first management for acc. fatigue.
1. Added lenses
Ill-sustained accommodation respond best to added plus
lenses
Suitable for pt with hard to stimulate accommodation.
1. Vision therapy (VT)
To restore normal accommodative function.
9. Management & Care Process
Plus lenses and vision therapy are effective in
treating ill-sustained accommodation. Vision
therapy is used to improve the speed of the
accommodative response, and it is generally
the treatment of choice. (AOA, 2011)
10. Management & Care Process
Vision therapy (VT)
3 phases
Table 1 : Objectives
Table 2 : Samples of VT program
20. Vision therapy
Re-evaluate about 3 to 4 weeks
If no improvement, there may be an underlying
organic basis to low AA.
Terminate VT, start with added plus lenses
If got improvement, re-evaluate till the end of
therapy.
Once VT completed, recommend home VT
maintenance programme.
21. Management & Care Process
Patient education
Accommodative anomalies are neuromuscular
problems and not refractive problems.
The effective treatment not only spectacles, but
active vision therapy to eliminate neuromuscular
dysfunction.
Prognosis & Follow up
Cooperation from patient for excellent prognosis
Follow-up: for this case, requires 12-24 in-office
visits
22. Case study: 13/C/M
Chief complaint:
Discomfort, blurred vision & tearing after 30-40 minutes
of reading.
Began about 6-9 months ago.
Had already been to see 2 doctors, but no eye problem
detected.
Ocularhistory:
Never had ocular problems & did not wear glass before
Health Condition:
Healthy and not taking any medication
Family History:
Unremarkable
23. Case study: 13/C/M (cont.)
Examination results:
Pupils were normal, colour vision normal, comitant deviation, all
external & internal health tests were negative
Test RE LE
VA (D/N) D: 6/6 ; N:6/6 D: 6/6 ; N:6/6
NPC 5cm
Covertest -D Orthophoria
-N
4 Exophoria
Subj RX Plano Plano
25. Case study: 13/C/M (cont.)
Accommodative assessment
Test RE LE
AA (Exp= 14D) 10D 10D
Repeated AA 8D 8D
MAF 5cpm (hard on minus &
performance deteriorates
after 30 secs)
5cpm (hard on minus &
performance deteriorates
after 30 secs)
BAF 3cpm (hard on minus & performance deteriorates
after 30 secs)
PRA -2.00D
NRA +2.50D
MEM +0.75D +0.75D
26. Case study: 13/C/M (cont.)
Diagnosis: Ill-sustained accommodation
Management :
(Patie nt & pare nts pre fe rre d the tre atm e nt witho ut the ne e d o f g lasse s)
Remember 3 options: Correction, added plus & vision
therapy.
Vision therapy was given as in Table 1 & Table 2.
18 visits of therapy done.
End of treatment results as following:
AA : 14D RE & LE
MAF : 18cpm RE & LE
BAF : 15cpm
MEM : +0.50D RE & LE
Patient now comfortable when reading , no discomfort.
Thus, dismiss from active VT, start maintenance
program
27. Case analysis
Distance & near phoria are both normal
Thus, the best initial approach to analyze
accommodative data:
Difficulty with MAF & BAF test:
Hard on minus lens
Overal cpm are borderline
Gradual deterioration with minus lens after 30secs
Amplitude of Accommodation (AA)
AA was repeated 10 times: Gradually decreased over time: Final
AA: 8D
Other findings within normal range
PRA: slightly reduced
MEM: high side of normal
28. Case analysis
This case is characteristic of Ill-sustained
accommodation.
Match the symptoms and complete
measurement of accommodative component
findings would help to elicit the diagnosis:
Accommodative facility test, repeated AA
measurement, MEM & PRA
One time measurement wont be able to elicit the
meaningful results.
29. Conclusion
Ill-sustained accommodation is a condition in
which the AA is normal, but fatigue occurs with
repeated accommodative stimulation.
It is medically necessary for the optometrist
to evaluate all accommodative components,
repeated measurement.
to diagnose the condition accurately
to discuss the diagnosis, risks & potential
treatment
30. References
1. Scheiman, M. & Wick, B., 2014. Clinical Management
of Binocular Vision: Heterophoric, Accommodative,
and Eye Movement Disorders (4th
ed.). Lippincott
Williams & Wilkins.
2. Cooper, J.S., Burns C.R., Cotter, S.A., Daum, K.M.,
Griffin, J.R., & Scheiman, M.M., 2011. Care of the
patient with Accommodative and Vergence
dysfunction. American Optometric Association.