PhD ceremony Ms. F. Maccioni: Evaluation of Crohn's disease activity: an integrated imaging approach

PhD ceremony: Ms. F. Maccioni, 11.00 uur, Academiegebouw, Broerstraat 5, Groningen

Dissertation: Evaluation of Crohn's disease activity: an integrated imaging approach

Promotor(s): prof. A. Signore, prof. R.A.J.O. Dierckx

Faculty: Medical Sciences

This thesis describes the diagnostic value of MRI in the evaluation of the inflammatory activity of Crohn’s Disease (CD). Both T1 and T2-weighted parameters can display relevant signs of mural inflammation in CD lesions, such as hypervascularity and oedema. Gadolinum-enhancement of the wall on T1-weighted imaging, signal hyperintensity of the wall and mesenteric fat on T2-weigted imaging were extensively analyzed, quantified and statistically correlated with the “biological” scores of activity. Moreover, MRI provides CD characterization (oedema versus fibrosis) and evaluation of intestinal extent of lesions and complications in the small and large bowel, which are also relevant issues in the management of the disease. We demonstrated that these features can be fully detected in adult and paediatric patients by optimizing at the outmost MRI techniques for evaluation of the bowel. Interestingly, using MRI we observed relevant differences in intestinal lesions distribution and in their activity between adult and paediatric patients.

Using generic radio-labelled radiopharmaceuticals, nuclear medicine has always demonstrated a similar sensitivity in detecting CD inflammation. Furthermore, the recent introduction of “specific” radiopharmaceuticals enables detection of specific inflammatory cytokines “in vivo”, addressing clinicians towards the most effective biological therapy. Thanks to recent technological advances, MRI may similarly assess microscopic changes in vivo within the intestinal wall, including oedema and fibrosis, vascular perfusion, diffusion of water molecules with Diffusion Weighted Imaging and molecular architecture with MR spectroscopy. The possible association of the two imaging modalities, now achievable with the PET-MRI cameras, could lead to a more comprehensive in vivo characterization of the disease, with still unexplored potentials.