Dissociated vertical deviation is a special type of hypertropia leading to slow upward drift of one or rarely both eyes, usually when the patient is inattentive.

The vertical miscoordination between the two eyes may lead to Hypertropia may be either congenital or acquired, and misalignment is due to imbalance in extraocular muscle function.

Specific & common causes include: Sudden onset hypertropia in a middle aged or elderly adult may be due to compression of the trochlear nerve and mass effect from a tumor, requiring urgent brain imaging using MRI to localise any space occupying lesion.

Steps to achieve the same depend on mechanism of the hypertropia and identification of the offending muscles causing the misalignment.

Specialty fellowship trained pediatric ophthalmologists and strabismus surgeons are best equipped to deal with these complex procedures.