Objective: To evaluate the role and validity of the Watzke-Allen test in following up patients after surgeries for an idiopathic full-thickness macular hole (FTMH).
Design: A prospective interventional analytical study.
Material and Method: Patients with idiopathic FTMH were consecutively recruited. A comparative analysis between preoperative and post operative visual acuity, macular hole status and Watzke-Allen slit beam test results was performed using a Chi-square test and a random intercept mixed model.
Results: Twenty-one patients with an average age of 65.90 + 6.05 years were included in the present study. Three months after surgery, macular holes were surgically closed in 13 eyes (61.9%) and still open in eight eyes (38.1%). An improvement in metamorphopsia, according to Watzke-Allen test results, was found in 61.53% of patients with closed holes and 87.5% of those with open holes. There was no statistically significant correlation between the Watzke-Allen test and the restorative status of a macular hole post surgery.
Conclusion: The Watzke-Allen test is a useful subjective assessment of visual function for diagnosis in patients with idiopathic FTMH. However, the test is not beneficial in the post operative follow-up of patients.

Keywords: Macular hole, Metamorphopsia, Optical coherence tomography (OCT), Watzke-Allen test