A method for estimating the physiological parameters defining the edema induced upon infusion of fluid from an intraparenchymally placed catheter including; a) acquisition of patient-specific medical data; b) estimation of pertinent tissue microstructure based on the patient-specific medical data and/or generalized information derived or drawn from one or more of the following: experience, literature, modeling, studies, research, analysis; c) acquisition of information about delivery parameters, and/or delivery device geometry, and/or fluid properties; and d) computing a field of values of predicted extracellular volume fraction over the tissue region using the information obtained in (b) and (c). According to a further aspect, a method of infusing or planning and/or monitoring an infusion of a contrast agent such that the distribution of such agent can be detected and observing and/or measuring the backflow length along the catheter track.