RESUMEN
·AIM: To report two patients with Helveston syndrome who received surgical treatment.·METHODS: During last year in department of oph-thalmology in West China Hospital, the surgery was designed to correct A-exotropia by lateral rectus' weaken and vertical offsets, and dissociated vertical deviation (DVD) by superior rectus muscles recession simultaneously.·RESULTS: A-exotropia and DVD of the patients vanished six months after the surgery. Both patients were clinically cured.·CONCLUSION: As the degree of horizontal and vertical strabismus was in the allowed range, complete examination and full assessment of the function of the four muscles were performed before operation, single operation can be considered in the treatment of Helveston syndrome.