Combining low- and high-resolution volume data for use in MR tracking

Abstract

The clinical pharmacology of morphine is complicated by its active metabolite, morphine-6-β-glucuronide (M6G). M6G is a potent μ-opioid agonist that has been recognized to play an important role in the clinical effects of morphine. However, M6G probably crosses the blood brain barrier with difficulties, and is of importance for the effects of morphine only during long-term morphine administration because only then M6G may reach high enough CNS concentrations. Since M6G is eliminated from the body via the kidney, it may cause severe opioid side effects with insidious onset and long persistence when renal function is impaired. This time dependent participation of M6G at the clinical effects of morphine makes it difficult to predict the effect of morphine in an individual patient. The problem may be solved using a PK/PD modeling approach to the clinical pharmacology of morphine that takes the delayed action of M6G into consideration.