MRI Temperature Mapping of the Prostate and Urogenital Pelvis Cooled by an Endorectal Balloon

Overview

Urinary incontinence and sexual dysfunction are potential side effects for men undergoing the successful removal of the cancerous prostate via surgery. Hypothermic cooling via the investigational Endorectal Cooling Balloon has been shown by our group to significantly reduce long term urinary incontinence and may reduce sexual dysfunction in men after robotic prostatectomy, and improve the patient's long term quality of life (QOL). However before successful translation of the endorectal balloon can proceed into the world wide usage, we must understand: 1. How effectively the tissues for continence and sexual function are cooled within the pelvis. 2. What is the capacity of vascularized structures (i.e. the neurovascular bundle) to 'cool sink' or diminish the effective cooling and 3. Determine if the endorectal balloon can be re-designed for improved QOL outcomes in men. This research study marries two new techniques of Thermal MRI imaging and Endorectal cooling for prostate cancer surgery. MRI is non-invasive. A simple confirmation of effective hypothermic cooling can be achieved by novel MRI thermal mapping of the cooling gradient as it comprehensively sweeps through the rectum across the urogenital pelvis. MRI with temperature adaptive software can accurately map these gradients with non-invasive technique, and answer formidable questions of the effectiveness of hypothermic cooling of the prostate and its direct translation into improved continence and sexual function after surgery. The purpose of this research study is to use Magnetic Resonance Imaging (MRI) and Thermal MRI with subjects who will receive the investigational endorectal cooling balloon to help further understand how the cooling balloon works, which may translate to other uses in the future, including the diagnosis of patients at a high risk of developing prostate cancer.

Prostate cancer is the second most frequent cause of cancer death in men and it accounts for 11% of all male cancers. Radical prostatectomy remains the gold standard for localized disease, offering the advantage of precise staging and grading and the real possibility of disease eradication. In the US there are approximately 100,000 radical prostatectomies (RP) performed for prostate cancer annually. However, there are two major challenges to the quality of life outcomes after radical prostatectomy: preserving urinary continence, and sexual function. The quality of life (QOL) after radical prostatectomy relies on the return of continence and sexual function after surgery to their pre-operative 'normal' status. The main factor which determines potency rates for patients is whether or not the nerves at the Neurovascular Bundles (NVB), are spared, and it may take years for sexual function to return. This may be due to the nerve injury from the nerve trauma in the surgical procedure. Similarly, a major factor involved in post-radical prostatectomy incontinence is preservation of the nerves that control the external urethral sphincter, bladder, and urogenital diaphragm. Also Inflammation from surgical removal of the prostate not only affects nerves, but also may directly damage the bladder, urethra, and pelvic floor. Effective strategies to prevent this damage are currently lacking. One stratagem to prevent or minimize such damage, is the use of local hypothermia with ice or cold irrigation around the nerves and tissues prior to, during, and after the injury has occurred. In numerous experimental models of central and peripheral nervous system injury, the use of moderate hypothermia (i.e. 28-33oC) has been shown to provide dramatic neuroprotection safely in humans, during cardiac, kidney, and brain surgery for many years.