Correspondence - ICO Library

-46-
Binocular Vision & Diagnosis and Surgical Treatm ent of Dissociated Horizontal Deviation Strabism us FIRST Quarter of 2011
Strabology Quarterly© S. Gam io, M D Volum e 26 (No.1)
A M edical Scientific e-Periodical Pages 43-50
prior strabismus surgery 4) visual acuity 5)
presence of amblyopia 6) refraction under
cycloplegia 7) dominant eye 8) presence of
head tilt 9) horizontal and vertical deviation
with each eye fixing 10) reversed fixation test
when available 11) oblique muscle
dysfunction 12) type of operation performed
13) final binocular alignment 14) length of
follow-up since the last surgery.
Ductions and versions were carefully
checked because lateral deviation
incomitancies due to weakness or restriction
could, at first sight, resemble DHD. Glasses
were used to correct refractive errors, and
thus prevent accommodation differences
between eyes.
The surgical plan was tailored to each
patient. It was sometimes changed because of
the eye position or the findings when
performing the spring back test and the forced
duction test under general anesthesia.
PATIENT GROUP CHARACTER
Twenty patients (See their data also in
Table 1, prior page) received surgery for
DVD and DHD in the 2000-2007 period.
Mean age at surgery was 11.7 years (4 to 36
years old). Seventeen patients (85 %) were
female.
All patients had a history of their
strabismus onset in the first year of life.
Nine patients had received prior
bilateral MR recession, 3 others had
spontaneous evolution from ET to orthotropia
or XT. One child received monocular surgery
(MR recession and LR resection), another one
had undergone Botox® injections in the
medial rectus muscles and bilateral Inferior
Oblique (IO) muscle weakening. The
remaining 6 patients had had no prior surgery.
The right eye was the dominant eye in
15/20 cases (75 %). Seven patients (35 %)
had amblyopia in the non-dominant eye.
Nine patients had XT, 9 ET and 2 had
ET when fixating with OS and and XT when
fixating with OD.
Six patients had Inferior Oblique
(muscle) OverAction (IOOA), 3 had Superior
Oblique (muscle) OverAction (SOOA), one
patient had both oblique muscles overacting
and the other 10 had normal oblique muscles
Reversed Fixation Test was performed
in 7 patients prior to surgery. (Table 2).
TABLE 2: Reversed Fixation Test (RFT)
DVD: Dissociated Vertical Deviation
ET: EsoTropia; XT: eXoTropia