Figure 4. Composite of images depicting the output of a multifunctional MRI and MRS study in locally advanced rectal cancer. (a) Axial T₂ weighted anatomical image (yellow arrows), (b) a K^trans map which depicts capillary permeability, (c) a relative blood volume map derived by exploiting the first pass T₂* effect. Note this tumour has a low blood volume (the high signal intensity anteriorly is the high blood volume within the body of a recently gravid uterus). (d) A diffusion weighted image. This quantitative map permits pixel-by-pixel analysis of tumour ADC (apparent diffusion coefficient). (e) A ¹H-MRS spectrum. ¹H-MRS can be used to probe tumour metabolism.