[Metabolic changes in brain cortex related with the strabismus treatment. Preliminary results with SPECT]

Our aim was to demonstrate metabolic changes occurring in brain cortex during strabismus treatment.

Single photon emission computed tomography (SPECT) of brain was made in patient with strabismus. The study only included congenital esotropia and excluded patients with other anomalies. Strabismus treatment was carried out with botulinum toxin or surgery. Brain SPECT was done prior to and after treatment. Changes were analyzed and related with strabismus response.

We studied three children with congenital and variable esotropia for a total of three cases. In Case 1, basal SPECT showed hypoperfusion in left frontal lobe (7.38). Response to botulinum toxin was good for correcting strabismus and obtaining binocularity from third month. Control SPECT showed correction of perfusion of frontal lobe (-1.19). With Case 2, we observed hypoactivity in left parietal area (8.59); after botulinum treatment, strabismus was corrected and binocularity was demonstrated, while control SPECT showed increase of hypoactivity levels (5.95). Finally, in Case 3, strabismus was corrected at surgery with binocularity. Basal SPECT demonstrated very important hypoactivity in right hemisphere, especially in areas 3, 4, and 5 areas (-0.7, -3.71, and -11.09, respectively); in addition, positive changes after treatment were demonstrated (9.78, 6.44, and 3.22, respectively).

Metabolic changes in brain cortex took place in congenital esotropia with SPECT. In all cases, brain SPECT could demonstrate changes after treatment with improvement of different areas, and good response of motor and sensorial state. This apparently is the first report concerning metabolic changes of brain cortex related with strabismus under treatment, and demonstrates the importance of brain cortex in genesis, evolution, and stability of visual functions and with regard to the failure of these in patients with strabismus.