Determination Of Predictive Factors Allowing To An Additional 10% Reduction Of Intra-Ocular Pressure

Inclusion Criteria: * Male or female patients, * Aged \> than equal to 18 years, * Patient presenting with an OHT or OAG with an IOP � 21 mmHg, * Patient currently treated with ophthalmic beta-blockers monotherapy and requiring a change of the ophthalmic medication due to insufficient response to treatment, Exclusion Criteria: * Patient currently treated by or having received within the last month any ophthalmic hypotensive agent other than a beta-blocker, * Patient presenting any contraindication to latanoprost or timolol, * Patient with history of asthma, obstructive broncho-pneumopathy, sinusal bradycardia (pulse rate \< 60 bpm), auriculo-ventricular block, cardiac insufficiency, Raynaud disease or any other condition that would preclude the patient from taking the prescribed medication, * Patient with known intolerance to benzalkonium chloride or any excipient contained in the trial treatment,