Corneal Confocal Microscopy to Detect Diabetic Neuropathy in Children
Condition: Type 1 Diabetes; Neuropathy; Retinopathy
MeSH terms: Peripheral Nervous System Diseases; Diabetic Neuropathies
Study type: Observational

Summary: 
      The overall aim of this study is to confirm the utility of corneal confocal microscopy (CCM)
      as a new technique to rapidly and non-invasively assess diabetic neuropathy (DN) in children.
      This study will be divided into two phases: Phase 1 will be a cross-sectional study of
      children with type 1 diabetes and normal controls, while phase 2 will be a longitudinal
      assessment of a subgroup of children with type 1 diabetes recruited during Phase 1.
    

Detailed description: 
      In phase 1: To compare corneal nerve density (CND), length (CNL), and branching (CBD) by CCM
      between

        1. children with type 1 diabetes for 5 years or more to children without diabetes;

        2. children with type 1 diabetes with and without evidence of diabetic neuropathy;

        3. to examine the relationship between CND, CNL & CBD and known risk factors of diabetic
           neuropathy

      In phase 2:

        1. to examine for changes in corneal nerve morphology two years after the initial CCM exam.

        2. to describe the evolution of diabetic neuropathy based on clinical symptoms,
           neurological deficits, and other tests of nerve dysfunction.

        3. to assess if changes in corneal nerve morphology correlate with changes in nerve
           conduction velocity and autonomic testing.

        4. To examine the risk factors associated with progression of diabetic neuropathy in our
           pediatric population.
    

Intervention name(s): Corneal Confocal Microscopy; Nerve Conduction Studies; Quantitative sensory testing; Neuropathy Symptom Score; Clinical nerve examination
Intervention type(s): Procedure; Procedure; Procedure; Procedure; Procedure
Intervention description(s): Close-up pictures of the front part of the eye (the cornea); The following assessments will be made: a) amplitude of nerve action potential (μV) and conduction velocity (m/s) of the sural sensory nerve by antidromic stimulation; b) motor nerve conduction velocity (m/s), maximum M-wave amplitude (mV) and motor nerve distal latency (ms) of the peroneal motor nerve; and c) tibial nerve conduction study will also be obtained if tolerated.; Standardized vibratory and thermal stimulation levels applied to the subject's non-dominant big toe.; A list of 18 motor, sensory and autonomic symptoms encountered in a diabetic patients with neuropathy obtained by interview.; Summated score of the lower extremities. Neurological examination assessing muscle strength, knee and ankle reflexes, sensation in the great toes will be evaluated for light touch-pressure, temperature, pin-prick, vibratory sense and joint position sense.
Observational model: Case-Control
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        Cases: Children seen at the Alberta Children's Hospital Diabetes Clinic in Calgary
        Controls: 8-18 year old healthy children
      
Keywords: Confocal microscopy; Cornea; Neuropathy; Detection; Diabetes