Abstract
Purpose :
To determine the most common treatment provided to patients with strabismus post plaque brachytherapy for choroidal melanoma. Secondary aims include determination of incidence and type of strabismus post plaque brachytherapy, and extraocular muscle most commonly removed and repositioned for plaque placement.
Methods :
This study involved patients diagnosed with choroidal melanomas between October 2011-2020. Demographic data collected included patient age, gender and city. Outcome data included presence of strabismus post-plaque brachytherapy, strabismus treatment received, pre-and-post-operative visual acuity, tumour dimensions, tumour distance from the optic nerve and fovea, duration of follow-up post-plaque surgery, extraocular muscles operated, and primary deviation following treatment. Patients that developed strabismus post surgery underwent strabismus classification into slipped muscle, sensory, decompensated phorias, cranial nerve palsies, restrictive or a combination of the above.
Results :
A total of 440 patients underwent plaque brachytherapy. 10/440 (2.27%) patients with treated choroidal melanoma developed strabismus. 7/440 (1.59%) patients were classified as having sensory strabismus, 2/440 (0.45%) slipped muscle, and 1/440 (0.22%) decompensating phoria. Of the 10 patients that developed strabismus, 1/10 (10.00%) is performing convergence insufficiency exercises, 2/10 (20.00%) require Fresnel for diplopia and are considering prism incorporation, 2/10 (20.00%) are awaiting consultation for strabismus surgery, 5/10 (50.00%) underwent strabismus surgery. Four of these patients had sensory exotropia and underwent lateral rectus recessions (1 had Botox prior to surgery). One patient had a combination of sensory exotropia and slipped muscle. Treatment for this patient included exploration and reattachment of the inferior rectus, superior rectus recession and Botox to the lateral rectus. A total of 389 muscles were removed and repositioned for plaque placement. The lateral rectus was the most common (157/389;40.36%), correlating to intraocular tumour location.
Conclusions :
The incidence of strabismus post plaque brachytherapy was 2.27% over 10 years. Strabismus surgery was the most common treatment modality, comprising 50% of treatment for strabismus patients. Sensory strabismus was the most common, occurring in 1.59% of patients. The lateral rectus was the most common muscle repositioned during surgery, comprising 40.36% of all muscles repositioned.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.