Thank kdlee.
My doctored informed me that I can choose between a normal (no glasses) far sight and difficulties with near-sight (reading, for example) and keeping my current glasses, gaining an almost normal reading capabilities. The new lense is a fixed size' and therefore, it set a norm' which can be adjust for further or neared sight.
Still, my question was phrased in more general perspective. Is there anything ELSE I should ask me doctor?