Ivo Gama1, Leonor Almeida1, Helena Fialho2, Conceição Crujo3. 1. Department of Ophthalmology, University Hospital Santa Maria, Medical Faculty of Lisbon, Lisbon, Portugal. 2. Department of Ophthalmology, University Hospital Santa Maria, Lisbon, Portugal. 3. Department of Anatomical Pathology, University Hospital Santa Maria, Medical Faculty of Lisbon, Lisbon, Portugal.