Adding automated decision-tree models to multiparametric MRI for parotid tumours improves clinical performance.

PURPOSE: Therapeutic management of parotid gland tumours depends on their histological type. To aid its characterisation, we sought to develop automated decision-tree models based on multiparametric magnetic resonance imaging (MRI) parameters and to evaluate their added diagnostic value compared with morphological sequences. METHODS: 206 MRIs from 206 patients with histologically proven parotid gland tumours were included from January 2009 to January 2018. Multiparametric MRI findings (including parameters derived from diffusion-weighted imaging [DWI] and dynamic contrast-enhanced [DCE]) were used to build predictive classification and regression tree (CART) models for each histological type. All MRIs were read twice: first, based on morphological sequence findings only, and second, with the addition of multiparametric sequences and CART findings. The diagnostic performance between these two readings was compared using ROC curves. RESULTS: Compared to morphological sequences alone, the addition of multiparametric analysis significantly increased the diagnostic performance for all histological types (p < 0.001 to p = 0.011), except for lymphomas, where the increase was not significant (AUC 1.00 vs. 0.99, p = 0.066). ADCmean was the best parameter to identify pleomorphic adenomas, carcinomas and lymphomas with respective cut-offs of 1.292 × 10-3 mm2/s, 1.181 × 10-3 mm2/s and 0.611 × 10-3 mm2/s, respectively. × 10-3 mm2/s. The mean extracellular-extravascular space coefficient was the best parameter to Warthin tumours from the others, with a cut-off of 0.07. CONCLUSIONS: The addition of decision tree prediction models based on multiparametric sequences improves the non-invasive diagnostic performance of parotid gland tumours. ADC and extracellular-extravascular space coefficient are the two best parameters for decision making.

Utility of a Suture-Mediated Closure System for Large Bore Arterial Access During Challenging Liver Intra-Arterial Catheters Implantation.

PURPOSE: To describe and study the utility of vascular suture-mediated closure systems for large bore arterial access during challenging implantation of liver intra-arterial catheters taking as a reference the conventional procedure involving patients without challenging anatomy. MATERIALS AND METHODS: Between January 2017 and January 2019, 61 consecutive patients underwent 65 intra-arterial catheter IAC implantations for colorectal cancer. Twenty-three procedures (35%) considered by the operators with challenging coeliac trunk angulations were treated using a vascular suture technique where a 6-F introducer was used, the other patients were treated with a conventional 4F access technique. Clinical and radiological characteristics of patients, technical success (implantation of catheters allowing safe infusion of chemotherapy) and complications (Common Terminology Criteria for Adverse Events, CTCAE 5.0) were recorded. RESULTS: Mean coeliac trunk angulations were 36.3° (± 14.3) for the vascular closure group and 49.6° (± 17.1) for the conventional group. Technical success of the procedures was 100% for the vascular closure group and 80% in the conventional group (p < .05). Four patients with technical failure in the conventional group had a successful IAC implantation on the second attempt using the vascular closure technique. The use of a suture-mediated closure system for large bore arterial access allowed more frequent positioning of the distal tip into the gastro duodenal artery (GDA) (p = .01). No major complication occurred. CONCLUSION: The use of a large bore arterial access combined with a suture-mediated closure system may be useful for challenging IAC implantation without major complications.