Abstract
Purpose :
The study aimed to determine if laterally selective temporal versus nasal GVRT of the IR can correct the lateral incomitance of small HT commonly encountered in SES.
Methods :
Records of all 77 consecutive patients who underwent adjustable GVRT of the IR under topical anesthesia by a single surgeon for correction of horizontally incomitant HT due to SES from July 2012 to August 2023 were reviewed. Previous strabismus surgeries, cranial neve palsies, trauma, and thyroid ophthalmopathy were excluded. Using topical lidocaine 1-2% anesthesia, GVRT was initialed from the nasal versus temporal side of IR corresponding to the greater HT. With patients seated upright, GVRT dosing was adjusted intraoperatively until orthotropia was indicated by alternate cover testing in central gaze.
Results :
GVRT was performed on the nasal side in 43 patients averaging 72±9 years old, and temporal side on 34 patients averaging 69±12 years old. Mean nasal GVRT was 69±16 % and mean temporal GVRT was 63±17%. Mean HT in central gaze was reduced by nasal GVRT from 3.7±1.5Δ to 0.4±0.9Δ , and from 4.2±2.2Δ to 0.4±1.3Δ by temporal GVRT. Nasal GVRT corresponding to the side of the tenotomy had greater effect in contralateral gaze at 3.2± 2.3Δ than ipsilateral gaze at 2.0 ± 2.1Δ, p=0.007, whereas temporal GVRT had greater effect in ipsilateral gaze at 5.2± 4.6Δ than contralateral gaze at 2.6±2.5Δ, p=0.0017. When the tenotomy exceeded 60%, the surgical effect in central gaze was significantly larger for temporal GVRT at 4.75 ± 1.86Δ then nasal GVRT at 3.4±1.5Δ, p = 0.0088.
Conclusions :
Nasal GVRT corrects about 1D and temporal GVRT 2.5D horizontal incomitance of HT. Selection of laterality of GVRT improves outcomes without additional risk or operating time.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.