Federico Collettini

Detection and classification of contrast-enhancing masses by a fully automatic computer-assisted diagnosis system for breast MRI

To evaluate a fully automatic computer‐assisted diagnosis (CAD) method for breast magnetic resonance imaging (MRI), which considered dynamic as well as morphologic parameters and linked those to descriptions laid down in the Breast Imaging Reporting and Data System (BI‐RADS) MRI atlas.

In vivo 3D neuroanatomical evaluation of periprostatic nerve plexus with 3T-MR Diffusion Tensor Imaging

OBJECTIVES To evaluate if Diffusion Tensor Imaging technique (DTI) can improve the visualization of periprostatic nerve fibers describing the location and distribution of entire neurovascular plexus around the prostate in patients who are candidates for prostatectomy. MATERIALS AND METHODS Magnetic Resonance Imaging (MRI), including a 2D T2-weighted FSE sequence in 3 planes, 3D T2-weighted and DTI using 16 gradient directions and b=0 and 1000, was performed on 36 patients. Three out of 36 patients were excluded from the analysis due to poor image quality (blurring N=2, artifact N=1). The study was approved by local ethics committee and all patients gave an informed consent. Images were evaluated by two radiologists with different experience in MRI. DTI images were analyzed qualitatively using dedicated software. Also 2D and 3D T2 images were independently considered. RESULTS 3D-DTI allowed description of the entire plexus of the periprostatic nerve fibers in all directions, while 2D and 3D T2 morphological sequences depicted part of the fibers, in a plane by plane analysis of fiber courses. DTI demonstrated in all patients the dispersion of nerve fibers around the prostate on both sides including the significant percentage present in the anterior and anterolateral sectors. CONCLUSIONS DTI offers optimal representation of the widely distributed periprostatic plexus. If validated, it may help guide nerve-sparing radical prostatectomy.

Diagnostic performance of a near-infrared breast imaging system as adjunct to mammography versus X-ray mammography alone

ObjectivesRadiologist reader performance for breast cancer detection using mammography plus Near-Infrared Breast Imaging (NIBI) was compared with mammography alone.MethodsTwo hundred seventy-six consecutive patients with suspected breast lesions underwent both mammography and NIBI. Four blinded radiologists independently first reviewed the mammograms alone. Readers subsequently reviewed the mammograms in combination with NIBI. The diagnostic benefit of NIBI as an adjunct to mammography was determined by performing receiver operating characteristics (ROC) analyses for each reader based on BI-RADS categories (Breast Imaging Reporting and Data System) and LOS (level of suspicion) scores. Additionally, a multireader-multicase (ROC) analysis of variance (ANOVA) was carried out.ResultsFor the LOS-based analysis, the combination of mammography and NIBI resulted in a slightly larger area under the curve (AUC) for all four readers. The analysis based on BI-RADS categories also demonstrated a slight increase in AUC for three readers for the combination of mammography and NIBI compared with mammography alone. For the fourth reader, AUC was smaller for the combination compared with mammography alone. Neither for the separate ROC-analyses nor for the ANOVA, significant differences between the two methods were obtained.ConclusionsThe combination of mammography and NIBI did not perform significantly better than mammography alone.Key PointsThe intrinsic contrast provided by optical breast imaging may be inadequateWe found slightly (but nonsignificant) higher accuracy for optical imaging and mammography compared with mammography alone.Contrast agents might be necessary to improve the performance of optical breast imaging

Computed-tomography-guided high-dose-rate brachytherapy (CT-HDRBT) ablation of metastases adjacent to the liver hilum

PURPOSE To evaluate technical feasibility and clinical outcome of computed tomography-guided high-dose-rate-brachytherapy (CT-HDRBT) ablation of metastases adjacent to the liver hilum. MATERIALS AND METHODS Between November 2007 and May 2012, 32 consecutive patients with 34 metastases adjacent to the liver hilum (common bile duct or hepatic bifurcation ≤5 mm distance) were treated with CT-HDRBT. Treatment was performed by CT-guided applicator placement and high-dose-rate brachytherapy with an iridium-192 source. MRI follow-up was performed 6 weeks and every 3 months post intervention. The primary endpoint was local tumor control (LTC); secondary endpoints included time to progression (TTP) and overall survival (OS). RESULTS Patients were available for MRI evaluation for a mean follow-up time of 18.75 months (range: 3-56 months). Mean tumor diameter was 4.3 cm (range: 1.3-10.7 cm). One major complication was observed. Four (11.8%) local recurrences were observed after a local tumor control of 5, 8, 9 and 10 months, respectively. Twenty-two patients (68.75%) experienced a systemic tumor progression during the follow up period. Mean TTP was 12.9 months (range: 2-56 months). Nine patients died during the follow-up period. Median OS was 20.24 months. CONCLUSION Minimally invasive CT-HDRBT is a safe and effective option also for unresectable liver metastases adjacent to the liver hilum that would have been untreatable by thermal ablation.

Unresectable colorectal liver metastases: percutaneous ablation using CT-guided high-dose-rate brachytherapy (CT-HDBRT).

PURPOSE To evaluate the clinical outcome of CT-guided high-dose-rate brachytherapy (CT-HDRBT) of unresectable colorectal liver metastases (CRLMs). MATERIALS AND METHODS Retrospective analysis of all consecutive patients with unresectable CRLMs treated with CT-HDRBT between January 2008 and November 2012. Treatment was performed by CT-guided catheter placement and high-dose-rate brachytherapy with an iridium-192 source. MRI follow-up was performed after 6 weeks and then every 3 months post-intervention. The primary endpoint was local tumor control (LTC); secondary endpoints included time to progression (TTP) and overall survival (OS). RESULTS 80 heavily pretreated patients with 179 metastases were available for MRI evaluation for a mean follow-up time of 16.9 months. The mean tumor diameter was 28.5 mm (range: 8 - 107 mm). No major complications were observed. A total of 23 (12.9 %) local tumor progressions were observed. Lesions ≥ 4 cm in diameter showed significantly more local progression than smaller lesions (< 4 cm). 50 patients (62.5 %) experienced systemic tumor progression. The median TTP was 6 months. 28 (43 %) patients died during the follow-up period. The median OS after ablation was 18 months. CONCLUSION CT-HDRBT is an effective technique for the treatment of unresectable CRLMs and warrants promising LTC rates compared to thermal ablative techniques. A combination with other local and systemic therapies should be evaluated in patients with lesions > 4 cm in diameter, in which higher progression rates are expected. KEY POINTS • CT-HDRBT enables a highly cytotoxic irradiation of colorectal liver metastases with simultaneous conservation of important neighboring structures (eg liver parenchyma, bile ducts and bowel)• The local tumor control rates obtained by CT-HDRBT in patients with colorectal liver metastases are promising, also compared to the local tumor control rates after RFA• Metastases with a diameter of 4 cm or abow, display a higher local progression rate after CT-HDRBT, therefor a combination therapy with other locoregional or systemic treatments should be investigated in prospective studies.

Percutaneous Computed Tomography–guided High-Dose-Rate Brachytherapy Ablation of Breast Cancer Liver Metastases: Initial Experience with 80 Lesions

PURPOSE To analyze initial experience with computed tomography-guided high-dose-rate brachytherapy (CT-HDRBT) ablation of breast cancer liver metastases (BCLM). MATERIALS AND METHODS Between January 2008 and December 2010, 37 consecutive women with 80 liver metastases were treated with CT-HDRBT in 56 sessions. Mean age was 58.6 years (range, 34-83 y). Treatment was performed by CT-guided applicator placement and high-dose-rate brachytherapy with an iridium-192 source. The mean radiation dose was 18.57 Gy (standard deviation 2.27). Tumor response was evaluated by gadoxetic acid-enhanced liver magnetic resonance (MR) imaging performed before treatment, 6 weeks after treatment, and every 3 months thereafter. RESULTS Two patients were lost to follow-up; the remaining 35 patients were available for MR imaging evaluation for a mean follow-up time of 11.6 months (range 3-32 mo). Mean tumor diameter was 25.5 mm (range 8-74 mm). Two (2.6%) local recurrences were observed after local tumor control for 10 months and 12 months. Both local progressions were successfully retreated. Distant tumor progression (new metastases or enlargement of nontreated metastases) occurred during the follow-up period in 11 (31.4%) patients. Seven (20%) patients died during the follow-up period. Overall survival ranged from 3-39 months (median 18 months). CONCLUSIONS CT-HDRBT is a safe and effective ablative therapy, providing a high rate of local tumor control in patients with BCLM.

CT fluoroscopy-guided percutaneous gastrostomy with loop gastropexy and peel-away sheath trocar technique in 31 amyotrophic lateral sclerosis patients

Background In amyotrophic lateral sclerosis (ALS) patients with respiratory impairment and/or advanced disease, performing even mild sedation – as is usually necessary for percutaneous endoscopic gastrostomy (PEG) placements – is fraught with risk. These patients are often referred to Interventional Radiology for alternative percutaneous gastrostomy tube placement options. Purpose To report our experience with CT fluoroscopy-guided percutaneous gastrostomy with a novel loop gastropexy and peel-away sheath trocar technique in ALS patients as an alternative to endoscopic techniques. Material and Methods A consecutive series of 31 amyotrophic lateral sclerosis patients in whom endoscopic gastrostomy was considered too dangerous or impossible to perform underwent CT-guided percutaneous gastropexy and gastrostomy and prospective follow-up. All procedures were performed with a 15 FR Freka® Pexact gastrostomy kit, a 16-row CT scanner (Aquilion 16) and single shot CT fluoroscopy mode. Results The procedure was performed successfully in 30 of 31 patients (20 men, 11 women; median age 60 years, range 38–80 years). In the remaining case the stomach was punctured under CT fluoroscopy and CO2 insufflation was initiated thereafter, leading to successful gastrostomy without prior gastropexy and without further adverse events during follow-up. Two patients reported unproblematic exchange of a balloon tube due to skin irritations with no further adverse events. One patient reported accidental displacement of an exchanged new balloon tube in domestic environment due to balloon leakage: A new balloon tube was easily re-inserted in a hospital the same day. No serious adverse events such as peritonitis, persistent local bleeding, systemic blood loss, or any local infection requiring surgical intervention were observed. Until August 11, 2011 follow-up resulted in 7473 cumulative gastrostomy-days from the date of first placement. Conclusion Initial results suggest that the described technique under CT guidance is feasible and safe and may especially be advantageous in cases where endoscopic gastrostomy and sedation are contraindicated.

Ischemic-Type Biliary Lesions After Ortothopic Liver Transplantation: Diagnosis With Magnetic Resonance Cholangiography

PURPOSE To determine the accuracy of magnetic resonance (MR) cholangiography for detection of ischemic-type biliary lesions (ITBL) following orthotropic liver transplantation (OLT). MATERIALS AND METHODS MR cholangiography was performed in 16 patients with established diagnosis of ITBL following OLT. Two blinded observers reviewed all images in consensus and recorded diagnostic features including presence of intrahepatic and extrahepatic biliary strictures, dilatations, beading, pruning, and filling defects. Sensitivity, specificity, positive predictive value, and accuracy of MR cholangiography were calculated. Final diagnosis was established at endoscopic retrograde cholangiography. RESULTS MR cholangiography proved to be a valuable tool for the detection of stenoses and dilatations in patients with ITBL following OLT. Sensitivity of the different diagnostic features ranged between 71% and 100%, specificity between 50% and 100%, accuracy between 81% and 100%, and positive predictive value between 87% and 100%. CONCLUSION MR cholangiography proved to be an accurate imaging technique to noninvasively detect biliary complications in patients with ITBL after OLT.

Lean manufacturing and Toyota Production System terminology applied to the procurement of vascular stents in interventional radiology

ObjectivesTo apply the economic terminology of lean manufacturing and the Toyota Production System to the procurement of vascular stents in interventional radiology.MethodsThe economic- and process-driven terminology of lean manufacturing and the Toyota Production System is first presented, including information and product flow as well as value stream mapping (VSM), and then applied to an interdisciplinary setting of physicians, nurses and technicians from different medical departments to identify wastes in the process of endovascular stent procurement in interventional radiology.ResultsUsing the so-called seven wastes approach of the Toyota Production System (waste of overproducing, waiting, transport, processing, inventory, motion and waste of defects and spoilage) as well as further waste characteristics (gross waste, process and method waste, and micro waste), wastes in the process of endovascular stent procurement in interventional radiology were identified and eliminated to create an overall smoother process from the procurement as well as from the medical perspective.ConclusionEconomic terminology of lean manufacturing and the Toyota Production System, especially VSM, can be used to visualise and better understand processes in the procurement of vascular stents in interventional radiology from an economic point of view.

CT-guided high-dose-rate brachytherapy in the interdisciplinary treatment of patients with liver metastases of pancreatic cancer.

BACKGROUND CT-guided high-dose-rate brachytherapy (CT-HDRBT) is an interventional radiologic technique for local ablation of primary and secondary malignomas applying a radiation source through a brachycatheter percutaneously into the targeted lesion. The aim of this study was to assess local tumor control, safety and efficacy of CT-HDRBT in the treatment of liver metastases of pancreatic cancer. METHODS Twenty consecutive patients with 49 unresectable liver metastases of pancreatic cancer were included in this retrospective trial and treated with CT-HDRBT, applied as a single fraction high-dose irradiation (15-20 Gy) using a 192Ir-source. Primary endpoint was local tumor control and secondary endpoints were complications, progression-free survival and overall survival. RESULTS The mean tumor diameter was 29 mm (range 10-73). The mean irradiation time was 20 minutes (range 7-42). The mean coverage of the clinical target volume was 98% (range 88%-100%). The mean D100 was 18.1 Gy and the median D100 was 19.78 Gy. Three major complications occurred with post-interventional abscesses, three of which were seen in 15 patients with biliodigestive anastomosis (20%) and overall 15%. The mean follow-up time was 13.7 months (range 1.4-55.0). The median progression-free survival was 4.9 months (range 1.4-42.9, mean 9.4). Local recurrence occurred in 5 (10%) of 49 metastases treated. The median overall survival after CT-HDRBT was 8.6 months (range 1.5-55.3). Eleven patients received chemotherapy after ablation with a median progression-free survival of 4.9 months (mean 12.9). Nine patients did not receive chemotherapy after intervention with a median progression-free survival of 3.2 months (mean 5.0). The rate of local tumor control was 91% in both groups after 12 months. CONCLUSION CT-HDRBT was safe and effective for the treatment of liver metastases of pancreatic cancer.