Functional Imaging of the therapeutic effect of Pregabalin in treatment for neuropathic pain in patients with Diabetic Polyneuropathy using proton Magnetic Resonance Spectroscopy (MRS):

The aim of our study is to investigate the effect of Pregabalin as a treatment for neuropathic pain in a homogeneous study population, using proton MRS (1H MRS) focusing on four regions of interest (bilateral thalami, rostral anterior cingulated cortex (rACC) and dominant dorsolateral prefrontal cortex (DLPC).

spectrum measurements at: thalamus left thalamus right rostral anterior cingulated cortex dominant dorsolateral prefrontal cortex

measurements: gamma-aminobutyric acid (GABA) glutamate (Glu) glutamine (Gln) N-acetylaspartate (NAA) Choline-containing compounds (Cho) Creatine plus phophocreatine (total creatine: Cr) Myo-inositiol (Ins) Choline (Cho) Glucose (Glc) Lactate (Lac)

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