Table 1.

Clinical EPR at Dartmouth

Clinical problem	Parameter to be measured	Status of measurements in human subjects	Rationale for using in vivo EPR measurements
Dosimetry	Radiation-induced free radicals	Extensive measurements underway	Fills unique niche for emergency dosimetry based on physical parameter
Peripheral vascular disease	Oxygen at sites of likely pathologies	Measurements underway in normal volunteers; patients to be studied in near future	The pO2 in the tissues is the most significant pathophysiological variable; no other method available to make such direct measurements. The pO2 measurements will facilitate evaluating progression of disease and success of therapeutic intervention
Cancer	pO2 in tumors	Measurements underway in patients with superficial tumors; IDEs submitted for permission to start studies with embedded materials	The response of tumors to cytotoxic therapy, especially ionizing radiation, is critically dependent on pO2. Antitumor therapies are given repeatedly and often change pO2. Knowledge of the changes in individual patients would significantly optimize the timing of the therapy
Wound healing	pO2 at various sites in wounds, Perhaps reactive oxygen species	Existing clinical protocols use an apparatus compatible with EPR measurements.	The pO2 is a critical variable for successful healing of wounds. Direct measurements would identify patients likely to have poor healing and follow responses to therapy
Radiation Induced Fibrosis	pO2 in irradiated tumor beds and peripheral normal tissue	Initial studies have been started	Radiation-induced hypoxia may play a critical role in the signaling of pro-inflammatory, pro-fibrotic, and pro-angiogenic growth factors and cytokines that lead to tissue fibrosis.