Search results
Results from the WOW.Com Content Network
Surgical correction. Surgical correction of the hypertropia is desired to achieve binocularity, manage diplopia and/or correct the cosmetic defect. Steps to achieve the same depend on mechanism of the hypertropia and identification of the offending muscles causing the misalignment.
The prism cover test ( PCT) is an objective measurement and the gold standard in measuring strabismus, i.e. ocular misalignment, or a deviation of the eye. [1] It is used by ophthalmologists and orthoptists in order to measure the vertical and horizontal deviation and includes both manifest and latent components. [1]
There are many possible types of misalignment that can occur after the surgery including undercorrection, overcorrection, and torsional misalignment. Treating a case of unsatisfactory alignment often involves prisms, botulinum toxin injections, or more surgery.
Prism correction is commonly specified in prism dioptres, a unit of angular measurement that is loosely related to the dioptre. Prism dioptres are represented by the Greek symbol delta (Δ) in superscript.
If adequate recovery has not occurred after the 6-month period (during which observation, prism management, occlusion, or botulinum toxin may be considered), surgical treatment is often recommended. [citation needed]
Incomitant strabismus cannot be fully corrected by prism glasses, because the eyes would require different degrees of prismatic correction dependent on the direction of the gaze.
Surgery or special glasses (prisms) may be advised if there is no recovery in 6 to 12 months. If diplopia turns out to be intractable, it can be managed as last resort by obscuring part of the patient's field of view.
While there was not enough high-quality evidence to recommend the best surgical treatment, all four types of surgery did result in a reduction of hypertropia.
Other options for strabismus management are vision therapy and occlusion therapy, corrective glasses (or contact lenses) and prism glasses, and strabismus surgery. The effects that are due only to the toxin itself (including the side effects) generally wear off within 3 to 4 months.
The test is indicated with the use of a presence of a prism in individuals with a strabismus and fusion is considered present if 4 lights are maintained, with or without the use of a prism. The W4LT can also be indicated when aiding a person to develop and strengthen their fusional capacities.