In a male child, from 2 months upwards, an aversion to light and nystagmus may lead to the suspicion of a case of<unk> , but it does not provide sufficient indications to establish the form of the condition. To identify a case of BCM, it is necessary to reconstruct the family history, with the condition linked to the transmission of the X chromosome if there are other cases in the family. The electroretinogram (ERG), can demonstrate the loss of<unk>  function with retained rod function. In adult individuals a color test like a Farnsworth D-15, a Farnsworth Munsell 100 Hue test can be part of the diagnosis tools and a Berson test makes it possible to distinguish<unk>  from other diseases. Visual acuity is usually tested in adults and is between 20/60 and 20/200.
Blue cone monochromacy
Optic nerve hypoplasia
Quadrantanopia
Macular hypoplasia
Congenital stationary night blindness
Cortical visual impairment
Cerebral achromatopsia
Associative visual agnosia