The second case is that of a 10-year-old girl who was referred from another centre for low vision with no apparent organic cause. The patient presented a report showing a visual acuity of 0.01 in both eyes with a refraction under cycloplegia of +1.00. All ophthalmological examinations were normal. The complementary tests presented visual evoked potentials (VEP), electroretinogram (ERG), angiofluoresceingraphy (AFG), computerised axial tomography (CAT), magnetic resonance imaging (MRI) also showed no alteration. Given the suspicion of simulation, we investigated the patient's family, school and social situation. She was the youngest of 4 siblings, with a large age difference, and in recent months she had begun to behave badly, with low grades at school, difficulty integrating with her classmates and, in addition, a sprain that forced her to use crutches. It was decided to carry out the lens confusion test: a +6.00 lens was placed in a trial frame and then progressively neutralised with negative lenses. Monocular VA was 0.8 and 0.6, respectively; and 0.8 in binocular vision. Stereopsis values were normal, 40". The parents were reassured about the child's condition and she was referred back to her referral centre for follow-up and monitoring.