[Criticism of the gonioscopic classifications of the glaucoma: with particular reference to the classification issued by the European Glaucoma Society in 2008].

PURPOSE: To critically analyze the gonioscopic classifications of glaucoma, especially of the classification issued by the European Glaucoma Society in 2008, in order to reveal its advantages and shortcomings.

METHODS: The paper tries to determine the extent to which this classification is clear (being based on a coherent and consistently followed set of criteria), is comprehensive (framing all forms of glaucoma), helps to understand the sickness (using a logical framing system), and facilitates therapeutic decision making (offering direct therapeutic suggestions).

RESULTS AND CONCLUSION: The paper shows that, compared with all the previous classifications, the 2008 European Glaucoma Society classification is one step ahead (in the way of classifying the group of secondary angle-closure glaucomas), two steps behind (in rejecting two useful categories of congenital glaucoma), and similar in several respects: that it is based on criticizable fundamental and secondary criteria that cannot cover all forms of sickness gathered at a particular crossing; that it uses several equally weighted criteria for one single crossing (division); that it frames one clinical entity in several clinical categories; that it does not reflect reality in some aspects; and that it does not offer direct therapeutic suggestions: after framing a case in a scheme built on the basis of gonioscopic observation, it requires a second stage of pathogenic analysis, so that the ophthalmologist is able to decide the correct treatment only in the third stage. This tortuous thinking pathway, with successive stages - that are not followed by all doctors, explains many of the erroneous therapeutic decisions. All these considerations justify the efforts to find a new classification, able to correct the abovementioned shortcomings.