The practical application of this challenge procedure involves placing a woman's hands into a basin of cold (approximately 11 degrees C) water for one minute between two sets of identically positioned images. The cold-water acts as an intentional challenge to the autonomic nervous system. The expected response to this challenge is a vaso-constrictive effect that will provide a uniform and bilaterally symmetrical cooling effect to the skin. The pre- and post-challenge images can be compared in order to evaluate a decrease in skin temperature as a result of an adaptive physiologic constriction in the caliber of normal blood vessels. This technique, then, contrasts the normal and reactive blood vessels from the non-responding blood vessels that are an important means of identifying neo-angiogenic and nitric oxide-dilated blood vessels characteristic of cancer. 

It is from our experience that the autonomic challenge greatly improves the specificity of breast thermology, diminishing the number of false-positive errors by differentiating non-cancerous inflammation or mastitis as a basis for atypical high-energy blood vessels (1). The autonomic challenge procedure also diminishes the number of false-negative errors by contrasting non-modulating blood vessels from other prominent blood vessels in the same or contralateral breast.



1. Hoekstra P, The autonomic challenge and analytic breast  thermology. Thermology International, 2004(14);3:106.