Hyperbaric oxygen therapy (HBOT) has been proposed to improve tissue quality, promote healing and prevent breakdown of irradiated tissue fields. Interestingly, the intermittent application of HBOT is the only intervention that has been shown to increase the number of blood vessels in irradiated tissue. This presentation will explore the mechanism of hyperbaric oxygen therapy to promote angiogenesis in tissues, and how it specifically relates to treatment of irradiation cystitis. The session will also provide a lively discussion and case studies regarding the presenter's experience in treating this condition with HBOT.