Functional Imaging of the Therapeutic Effect of Pregabalin in Treatment for Neuropathic Pain

Inclusion Criteria: * Age ≥ 18 years * Patients with painful DPN * Patient willing to provide informed consent * Type 1 or type 2 diabetes with HbA1c ≤ 11% * Stable antidiabetic medication for 30 days prior to randomization * Duration of painful DPN ≥ 3 months * Visual analogue scale (VAS) score ≥ 4 Exclusion Criteria: * Creatinine clearance ≤ 60mL/min * Presence of other clinically significant or disabling chronic pain condition * Active malignancy * Evidence of an active disruptive psychiatric disorder or other known condition that might influence the perception of pain, compliance to intervention and/or ability to evaluate treatment outcome as determined by the investigator * Life expectancy less than 1 year * Existing or planned pregnancy * Extreme fear for entering MRI * General contraindication for MRI (pacemaker, etc…) * Patients participating in other clinical trials * Age \<18 years * Prior use of potential retinotoxins * Prohibited medications without proper wash-out period (\>7days, depending on the type of medication): * medications and supplements commonly used for relief of neuropathic pain * antiepileptics * antidepressants (except for stable regiments of SSRIs for treatment of anxiety or depression) * NSAID