Telecanthus refers to increased distance between the medial canthi of the eyes, while the inter-pupillary distance is normal. This is in contrast to hypertelorism, where the inter-pupillary distance is increased. The distance between the inner corner of the left eye and the inner corner of the right eye, is called intercanthal distance. In most people, the intercanthal distance is equal to the distance between the inner corner and the outer corner of each eye, that is, the width of the eye. The average interpupillary distance is 60–62 millimeters ,which corresponds to an intercanthal distance of approximately 30–31 mm.The situation, where intercanthal distance is intensely bigger than the width of the eye, is called telecanthus Telecanthus is often associated with many congenital disorders such as Down syndrome, fetal alcohol syndrome, Cri du Chat syndrome, Klinefelter syndrome, Turner syndrome, Ehlers-Danlos syndrome often present with prominent epicanthal fold and if these folds are nasal they will cause telecanthus.
