When Thanh's strabismus was first detected, his vision in both eyes was normal (10/10), so doctors opted for observation. Recently, Thanh was examined at Tam Anh General Hospital, where both eyes showed a deviation of approximately 47 prism diopters, equivalent to 25-27 degrees of misalignment.

Master of Science (MSc), Doctor Duong Minh Phuc, from the High-Tech Eye Center, explained that six extraocular muscles control human eyes, working in sync to focus both eyes on a single target. When the balance between these muscles is disrupted, the eyeball deviates from its visual axis, resulting in strabismus.

Doctor Phuc examines Thanh's eyes. *Photo: Tam Anh General Hospital

Strabismus affects not only appearance but also reduces binocular coordination. According to Associate Professor, Doctor Nguyen Thanh Nam, Director of the High-Tech Eye Center, if left untreated, the condition can lead to amblyopia and double vision. This can also impact a child's learning, communication, and psychological well-being. Following a consultation, doctors recommended surgery to adjust the extraocular muscles.

Strabismus surgery involves more than just "straightening the eyes"; it re-establishes the balance of the extraocular muscle system. Before the operation, doctors must precisely measure the angle of deviation, assess the pulling strength of each muscle, and calculate the appropriate degree of adjustment for each patient.

Associate Professor Nam noted that the most challenging aspect is determining which muscle to adjust and by how much. If a muscle is recessed insufficiently, the eye may remain misaligned; if recessed too much, the eye could deviate in the opposite direction. "An error of just a few tenths of a millimeter can affect the outcome", Associate Professor Nam stated.

Associate Professor Nam performs strabismus surgery on Thanh. *Photo: Provided by Hospital

During the surgery, the team adjusted Thanh's two medial rectus muscles based on previously calculated parameters. The operation was completed in under one hour. At a follow-up appointment one week later, the patient's eyes had returned to their correct physiological alignment.

Associate Professor Nam advised parents to seek an eye specialist examination for children if they observe misaligned eyes, frequent head tilting, squinting, or a deviated gaze. Early detection and treatment of strabismus increase the chances of visual function recovery and prevent long-term psychological impact.

Ngoc Kim Tham

*Patient's name has been changed