Peripheral Autonomic Neuropathy

When a stimulus causes backward nerve transmission, vasodilation of the innervated blood vessels occurs; this is the axon reflex, also referred to as the flare response. An impaired axon reflex indicates peripheral neuropathy. In practical terms, when skin is heated (by using the moorVMS-HEAT) or iontophoresed (by using the moorVMS-ION) with acetylcholine over a well defined area, microvascular blood flow also increases in the surrounding skin (as well as at the site stimulated). Laser Doppler monitoring (moorVMS-LDF) is used to assess the magnitude and time course of the vasodilation, and additional information on the flare area can be obtained with laser Doppler (moorLDI2) and Speckle imaging (moorFLPI-2).

Equipment Recommendations

The moorFLPI-2 with high speed and spatial resolution is the system of choice, coupled with moorVMS-ION iontophoresis and ION6 chambers + CAP.

Laser Speckle Contrast Imager

Full-field, video frame rate blood flow imaging

Laser Speckle Imager | moorFLPI-2

What Next?

Contact us to discuss your specific needs and to request your copy of our free Application Note which includes a detailed experimental method and practical suggestions. We also offer no obligation on-site visits so you can test the equipment in your facility.


Ahluwalia P, McGill J I, Church M K.
Nedocromil sodium inhibits histamine-induced itch and flare in human skin.
British Journal of Pharmacology. 2001, 132, 613-616.

Bickel A; Kramer H H; Hilz M J; Birklein F; Neundorfer B, and Schmelz M.
Assessment of the neurogenic flare reaction in small-fiber neuropathies.
Neurology 2002; 59, 917-919.

Caselli A, Rich J, Hanane T, Uccioli L, and Veves A.
Role of C-nociceptive fibers in the nerve axon reflex-related vasodilation in diabetes.
Neurology 2003: 60, 297-300.

Krishnan STM and Rayman G.
The LDIflare: A novel test of C-fiber function demonstrates early neuropathy in type 2 diabetes.
Diabetes Care 27:2930–2935, 2004.