Binocular Vision &

Eye Musck Surgery Qtrly°

Major Review: !ntennittcnt Exotropia

Basic and Divergence Evcess Type J. Cooper, MS, OD and N. Medow MD

Summer of 1993

Volume 8 (No.3): 185-216

TABLE IV:

Scott A., Marsh and Jampolsky’s* Linear Regression Calculation

of the Amount of Surgery

for Bilateral Lateral Rectus Recession for Exotropia

Mean partial

regression

coefficient

Patients

in effect

measure.

Total

per unit

Example

change

Preop’ deviation (A)

.0544 X

1.9040

Difference bet dist

.0164 X

0.1640

& near measure (A)

Age (yrs) at surgery

-.0692 X

6.5 yrs

-.4490

Refractive spherical

.0473 X

+1.00

0. 0473

equivalent (D)

Change in deviation

.007 1 X

0.00

in upgaze (A)

Change in deviation

.0199 X

0.00

in downgaze (A)

Mean change per mm

1.0490

of recession

(constant derived

by Scott et al)

Effect per mm

2.7160

final calculation of surgery:

mm recession per lateral rectus =

Preop’ deviation = 35/2x(2.71620) = 6.5 mm recession for each LF

2 X effect per mm

* Scott AB, Marsh AJ, Jampoisky A: Quantitative guidelines for exotropia surgery. Invest Ophthalmol 1975;

14:428-436.

the older population. They evaluated 44 exotropic patients aged 15-70 years, whose presenting symptoms were asthenopia (33%), diplopia (29%), difficulty reading (20%), headaches (20%), and cosmesis (7%). They performed a recess-resect on 39 patients. Their findings indicate that

overcorrection often resulted in diplopia in this age group. Therefore, they advocated deliberate undercorrection in this age group. They reported 29 of the 39 had significant improvement, i.e., deviation less

than 15 pd and a reduction of symptoms.

The older a patient becomes, the more

ingrained the habitual visual-motor relationship. This relationship should not be altered. Thus it is wiser to leave an adult exotropic patient on the exo side postoperatively rather than on the eso side.

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