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June 1988
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Orthoptics
for
Convergence Insufficiency—Cooper
461
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FIG. b.
Asthenopsa
and
accommodative amplitude for three
conditions is
presented: baseline, phase 1, and phase 2.
Between
phase 1
and
phase 2 the
experimental
group, which had monocular accommodative therapy. became
the
control group (placebo therapy) and vice versa It is clear that accommodative therapy decreased asthenopia
and
improved accommodative amplitude. (Repnnted from Am J Optom Physiol Opt 1987:64:433.)
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target
changed
smoothly
and rapidly from a
preset BO to a
preset
B! value. The speed of the
target
was systematically changed from 2.50^/s
to 10^/s and the target separation
speed varied between 45^
BO
and
10^
BI.
After
12 sessions she showed orthophoria at distance and a small exophoria at near (40 cm)
with
the cover test. NPC was to the nose;
prism
vergence ranges using a
muscle
light with the
Krimsky technique revealed
BO >45; occlusion to break fusion resulted in an immediate recovery. B! ranges were 20/15^. Topper
vectogram
fusion ranges were BO >33^ and B! 14/4k. RDS BO ranges were full
(greater
than 55^)
and
B! were 22/15^. In summary, there was no evidence of the convergence insufficiency
and
no further report of diplopia or headaches. The patient has
been
followed for 2 years without a recurrence
of symptoms.
This
girl
was an extremely bright
and
academically successful 10-year-old. She had a long history of constant diplopia with reading, which she relieved by occluding her eye with her hand. Her family history
indicated
that her mother
also
bad
a convergence insufficiency.
Unaided visual
acuity
was
6/6 (20/20) each eye. No refractive error was found. Cover testing at distance showed orthophoria,
and
at near 15^ constant exotropia. NPC
was
51/63 cm with diplopia occurring during deviation. Extraocular movements were full and concomitant. Testing revealed the following: distance phoria 1^ exo; distance BO X/1/0; distance B! X/1/0; near phoria 15
A
exo; near BO X/-16/-15^; B! X/ 17/16^ (measured from the phoria). She responded to the 20 sec
arc
target on the original
Randot
test at 50 cm.
Stereopsis
was
observed
on Topper
vectogram
at 50 cm. As
soon as
the
vectogram was separated
in either a BO or B!
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direction diplopia was noted. Fusional ranges were nonexistent. Testing using either a large target or RDS on the Computer Orthopter resulted in the same phenomenon. Accommodative testing demonstrated reduced positive relative accommodation (—1-00 D) and negative relative accommodation
(+1.00
D), respectively, monocular accommodative amplitudes were normal(1OD).
Office
therapy began with
Vectograms
and the Computer Orthopter
large fusion targets
and
RDS vergence
program.
The patient
was told to
separate
the
targets
slowly in a
massaging
motion (BO
and 131)
while trying
to
maintain fu sion. She was given Brock
string, Vectograms, and pushups
for home therapy. After four sessions, no further
progress
was made. The patient
was
frustrated
in not knowing what to do with her eyes. On the fifth session
limited
fusion
ranges
were obtained on the RDS
vergence pro
gram, i.e., 5^.
Two
sessions later BO ranges were
l0^
BO
and
3^ B!.
Vectogram
ranges were BO 3/1^ and BI 3/1^. By the eighth session the patient had
learned to make
real vergence movements. RDS ranges improved rapidly
to
BO 25^ and
to
B!
10^;
vectogram
ranges improved
to
BO 25/10^
and
B! 11/1^.
She now
reported
less diplopia and a decrease in asthenopia. Within 9 to 10 sessions, vergence improved rapidly to BO
=
45^
and B!
=
12g. However, vergence movements could only be maintained if separation
was
slow.
Pushups
and Brock string performance improved dramatically (convergence to 2.5 cm). At this point the
goal
was to increase the
speed
of separation. Using a
manual
vergence program, vergence demand was increased slowly from 2.5^/s to 10^/s (#9 to #1 setting). Target
size was decreased.
Next the auto program
was used
to
build sustaining ability. Disparation occurred automatically between BO
=
30^ and B!
=
10g. The
speed
was
set
at
7^/s.
This was done for 5 min
before
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