Post-thyroidectomy iatrogenic Horner's syndrome with heterochromia

To present a case of iatrogenic Horner's syndrome seen together with the heterochromia in the post-thyroidectomy period.
A23-year-old female patient was admitted to our clinic with complaints of lowvision in the eye and difference in eye color that developed over the past two years. In the left eye, myosis and minimal ptosis (~1 mm) was detected, and the color of the iris was lighter than the right eye.
The pre-diagnosis of left iatrogenic Horner's syndrome was finalized after 0.5% topical apraclonidine test.
Heterochromia can be observed in iatrogenic Horner's syndrome.