This is a typical case of antimongoloid fissure esotropic infant  , those infants usually present with :

1.             Infantile esotropia

2.            V pattern strabismus , usually XT in up gaze

3.             Inferior Oblique overaction manifests as vertical incmoitance in up & in gazes

These features must be put in mind when surgically correcting the esotropia . All these could be corrected simply by adding downshifting the recessed 2 MR and /or by doing  bilateral IO myectomy

It is obvious that this was not done here , the esotropia is really perfectly corrected , still the parents of these infants always complain about the residual vertical incomitance on looking up and on looking up & in caused by the overaction of the Inferior oblique muscles

The Decision :

In a case like this I don't prefer to do detachment of the 2 MR & reattach them down since this may occasionally affect the perfect horizontal alignment

I prefer to do bilateral IO myectomy since this will not affect neither the horizontal nor the vertical alignment in the primary position , but it will sure correct the vertical incomitance on looking in & up gazes , it will also correct the up exotropia.

The homily is : in every case of infantile esotropia don't forget 2 looks :

one look to the palpebral fissure , second ,look for the usual variable findings , they are more usual than you think

Strabismus Course : Esodeviations