Evaluation of the FOCUS Diffusion's Added Clinical Value Compared to Conventional MRI

The radiologist plays a key role in the management of pancreatic tumours, which are potentially serious. While the scanner, with its high spatial resolution, plays a major role in pancreatic pathology, and in particular in the assessment of operability, MRI, with its good contrast resolution, has proven its contribution to the detection and characterization of focal lesions. Each MRI examination consists of several series of images called sequences, each with its own particularity, to highlight different types of abnormalities such as edema, bleeding, tumor content or vascularization. All the sequences performed constitute a "protocol". The diffusion sequence is a technology that allows the microscopic random movements of water molecules to be translated into images. It thus makes it possible to differentiate between certain aggressive tumours which are characterised by a higher cell density than healthy tissue, in which water molecules do not circulate freely, benign lesions such as cysts in which the circulation of water molecules is not hindered. The calculation of the Apparent Diffusion Coefficient (ADC), an estimate of the diffusion rate of water molecules, is a quantitative diagnostic tool validated in many fields of application and in particular in oncology.

Sex

All

Minimum age

18 Years

Inclusion Criteria:

* Male or female whose age ≥ 18 years old (Adult patient)
* Francophone patient
* Pancreatic MRI performed at the GHPSJ on 3 Tesla MRI between September 2014 (date of introduction of the FOCUS diffusion sequence) and April 2018
* Presence of at least one proven benign or malignant focal pancreatic lesion visible on at least one of the MRI sequences

Exclusion Criteria:

* Patient under guardianship or curatorship
* Patient deprived of liberty
* Patient objecting to the use of their data for this research
* Papillary and mucinous intra-channel tumour of pancreas (TIPMP) of secondary channels measuring less than 30mm.

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