Effect of repeated peribulbar triamcinolone acetate injection on corneal topography in patients with thyroid eye disease
First Author: N.Elfarouk EGYPT
Co Author(s): H. ElRashidy
To determine the effect of repeated triamcinolone peribulbar injections as a line of treatment of Thyroid Eye Disease (TED) on corneal topography and subsequently on patient's refraction and visual outcome.
Memorial Institute of Ophthalmic Research.
Thirty patients' eyes with mild to moderate TED who underwent repeated peribulbar injections of 20 mg Triamcinolone Acetate (40 mg/ml) for four doses with one week interval. The injections were done in the operation theater using 0.5 ml of a 40 mg/ml Triamcinolone Acetate solution injected in the peribulbar space of the orbit through the inferolateral quadrant using a 23 guage syringe under complete sterile conditions. Preoperative and three months postoperative Corneal Topography with Occulus Pentacam were done, Astigmatism amplitude together with the Steepest meridian and its axis in the 3 and 5 mm zone were obtained.
Our data clearly showed that repeated peribulbar Triamcinolone injections in patients with TED significantly affected the corneal curvature resulting in significant change in the steepest meridian (k max) and the astigmatism amplitude, while the astigmatism axis showed no significant changes. The K max measured with pentacam showed mean of 43.87±2.07SD and 43.29±1.99SD pre and postoperative respectively (p<0.001), while Pentacam Astigmatism was 2.19±1.40 preoperatively and 1.41±0.93 postoperatively (p<0.001). Moreover, to the best of our knowledge, no reported study has evaluated the changes in corneal topography after repeated Triamcelonone peribulbar injections as an alternative to surgery.
In conclusion, we have demonstrated that a significant change in corneal curvature occurs after repeated peribulbar injection of Triamcinolone Acetate in patients with TED. The amount of this change in corneal curvature is sufficient to change the postoperative refraction of the eye that as present will render any refractive procedure better postponed after TED treatment for all patients. Thus, a detailed preoperative consultation is essential for all patients undergoing these injections.