Emanuele Neri

Detection of biliary complications after orthotopic liver transplantation with MR cholangiography

To assess the diagnostic value of magnetic resonance cholangiography (MRC) when evaluating biliary complications in the follow-up of liver transplant patients. One hundred and thirteen patients prospectively underwent MR imaging and MR cholangiography at 1.5-T unit after orthotopic liver transplantation (OLT). After the acquisition of axial T1- and T2-weighted sequences, MRC involved a coronal, non breath-hold, respiratory-triggered, fat-suppressed, two-dimensional, thin-slab, heavily T2-weighted fast spin-echo sequence, and coronal breath-hold, thick-slab, single-shot T2-weighted sequences. The images and maximum intensity projections were evaluated by two readers in order to determine biliary anatomy and the presence of complications, whose final diagnosis was based on endoscopic retrograde cholangiography (ERC) in 50 patients, percutaneous trans-hepatic cholangiography (PTC) in five, and by integrating clinical follow-up with ultrasound and MR findings in 58 cases. MRC had a sensitivity of 93%, a specificity of 92%, a positive predictive value of 86%, a negative predictive value of 96%, and a global diagnostic accuracy of 93% in detecting all types of biliary complications in OLT patients. MRC is a reliable technique for detecting post-OLT biliary complications. We now restrict the use of ERC to patients for whom therapeutic procedures are advocated or whose MRC results are equivocal.

80-kV Pulmonary CT Angiography With 40 mL of Iodinated Contrast Material in Lean Patients: Comparison of Vascular Enhancement With Iodixanol (320 mg I/mL)and Iomeprol (400 mg I/mL)

OBJECTIVE The purpose of this article is to compare the vascular enhancement obtained with a low-kilovoltage pulmonary CT angiography (CTA) protocol in lean patients, using 40 mL of a moderate-concentration isoosmolar (iodixanol, 320 mg I/mL) and a high-concentration low-osmolar (iomeprol, 400 mg I/mL) iodinated contrast medium injected at the same iodine delivery rate. SUBJECTS AND METHODS Forty-two lean patients (31 men and 11 women; body mass index, ≤ 23 kg/m(2)) with suspected pulmonary embolism and non-small cell lung carcinoma underwent pulmonary CTA with a 64-MDCT scanner using a tube voltage of 80 kV. Twenty-three patients (54.8%) received 40 mL of iodixanol (320 mg I/mL) injected at a rate of 5 mL/s, and the remaining 19 patients (45.2%) were administered an equal volume of iomeprol (400 mg I/mL) at a flow rate of 4 mL/s. Intraarterial density was measured in the common pulmonary artery trunk, the main right and left pulmonary arteries, lobar arteries, and at the segmental level, for a total of 15 regions of interest per patient. Intravascular enhancement homogeneity from central to subsegmental level was also assessed visually using a semiquantitative score (1 = poor, 2 = good, and 3 = excellent). RESULTS The overall vascular density of pulmonary arteries down to the segmental level was significantly higher with iodixanol (320 mg I/mL) than with iomeprol (400 mg I/mL) (p = 0.036). Enhancement homogeneity was good with both contrast agents, with no statistically significant difference between them (p = 0.8966). CONCLUSION In 80-kV pulmonary CTA of lean patients, higher intravascular enhancement can be achieved with 40 mL of iodixanol (320 mg I/mL) than with the same volume of iomeprol (400 mg I/mL), with good vessel conspicuity down to the subsegmental level.

The future of PACS in healthcare enterprises

Picture Archiving and Communication System (PACS), which was originally designed as a tool for facilitating radiologists in interpreting images more efficiently, is evolving into a hospital-integrated system storing diagnostic imaging information that often reaches far beyond Radiology. The continuous evolution of PACS technology has led to a gradual broadening of its applications, ranging from teleradiology to CAD (Computer-Assisted Diagnosis) and multidimensional imaging, and is moving into the direction of providing access to image data outside the Radiology department, so to reach all the branches of the healthcare enterprise. New perspectives have been created thanks to new technologies (such as holographic media and GRID computing) that are likely due to expand PACS-based applications even further, improving patient care and enhancing overall productivity.

CT perfusion of head and neck tumors: how we do it.

OBJECTIVE Our purpose is to illustrate the pathophysiologic, physical, and technical principles of MDCT perfusion imaging of head and neck tumors. The rationale for data acquisition and the interpretation of perfusion parameters will be discussed in the context of results recently published in the literature. CONCLUSION MDCT perfusion imaging of primary and recurrent head and neck tumors is feasible and can yield functional information that is useful for tumor grading and assessment of treatment response.

MULTIDETECTOR CT AND VIRTUAL ENDOSCOPY IN THE EVALUATION OF THE ESOPHAGUS

Abstract In this prospective study, we assessed the diagnostic capabilities of multidetector computed tomography (CT) in various esophageal pathologic conditions. Thirty-three patients underwent a multidetector CT study after esophageal distention by means of effervescent powder administered after induction of pharmacologic esophageal hypotonia. All acquired images were post-processed with two- and three-dimensional software tools. The CT data were compared with the results of conventional radiology (33), endoscopy (28), endoscopy ultrasonography (14), or surgery (14). Follow-up ranged between 4 and 15 months. Esophageal distention in the upper and middle thirds was classified as “good” in 32 of 33 cases (97%); in the lower third, esophageal distention was “good” in 21 of 33 cases (64%). Final diagnoses were leiomyoma (six cases), squamous cell carcinoma (six), adenocarcinoma (four), esophageal infiltration by thyroid cancer (two), benign polyposis (two), chronic esophagitis (five), post-sclerotherapy stenosis (one), no abnormalities (seven). When good distention was achieved, the thickness of unaffected esophageal wall was less than 3 mm (range, 1.5–2.4 mm; mean, 1.9 mm). Pathologic wall thickening was observed in 25 of 33 cases (76%), with values ranging between 3.6 and 36 mm (mean, 9.6 mm). Spiral CT demonstrated 21 true positive cases, and seven true negative cases. There were four false negative cases and one false positive case. Sensitivity was 84%, specificity was 87%, diagnostic accuracy was 85%, positive predictive value was 95%, and negative predictive value was 64%. Evaluation of the esophagus with multidetector CT is a promising technique and easy to use, allowing panoramic exploration, virtual endoluminal visualization, accurate longitudinal and axial evaluations, and simultaneous evaluation of T and N parameters.

Virtual endoscopy of the middle ear

Abstract Virtual endoscopy is a computer-generated simulation of fiberoptic endoscopy, and its application to the study of the middle ear has been recently proposed. The need to represent the middle ear anatomy by means of virtual endoscopy arose from the increased interest of otolarygologists in transtympanic endoscopy. In fact, this imaging method allows the visualization of middle ear anatomy with high detail, but it is evasive and is essentially used for surgical guidance. Virtual endoscopy provides similar perspectives of the tympanic cavity but does not require the tympanic perforation. In the study of the middle ear, specific attention is given to the retroperitoneum. This region contains elevations of the medial wall (pyramidal eminence and ridge, styloid eminence and ridge, subiculum, ponticulus) and depressions (sinus tympani, posterior sinus tympani, facial sinus, fossula of Grivot, oval window fossula), which can be effectively displayed by virtual endoscopy. Virtual endoscopy is foreseen as a useful tool in preoperative management of patients who are candidates for middle ear surgery, since it can predict with high detail the patients specific anatomy by imaging perspectives familiar to otosurgeons.

Efficacy of Computer-aided Detection as a Second Reader for 6–9-mm Lesions at CT Colonography: Multicenter Prospective Trial

PURPOSE To assess the effect of computer-aided detection (CAD) as a second reader on the sensitivity and specificity of computed tomographic (CT) colonography in detecting 6-9-mm colorectal cancer (CRC) lesions. MATERIALS AND METHODS Individuals with clinical indications for colonoscopy--either for symptoms or as part of participating in a surveillance program or CRC screening--were prospectively enrolled at one of 10 academic centers between July 2007 and May 2009. Institutional review board approval was obtained at each clinical site, and all participants provided written informed consent. All participants underwent CT colonography and colonoscopy on the same day. Experienced readers interpreted the CT colonography images unassisted and then reviewed all colorectal lesion-like structures pinpointed by the CAD algorithm. Segmental unblinding of CT colonoscopy findings at colonoscopy was utilized. The sensitivity and specificity of unassisted and CAD-assisted reading in identifying individuals with 6-9-mm lesions were calculated and compared by means of pairwise analysis. RESULTS A total of 618 participants (mean age, 57.9 years; 54.5% male) were included in the final analysis. Of these participants, 464 (75.1%) had no lesions 6 mm or larger, and 52 (8.4%) had 6-9-mm lesions. The sensitivity of CT colonography with unassisted reading and that with CAD-assisted reading in identifying individuals with 6-9-mm lesions was 65.4% (95% confidence interval [CI]: 50.9%, 78.0%) and 76.9% (95% CI: 63.2%, 87.5%; P = .016), respectively. No significant change in specificity was observed: The specificity of CT colonography with unassisted and that with CAD-assisted reading was 91.8% (95% CI: 88.9%, 94.1%) and 90.9% (95% CI: 88.0%, 93.4%; P = .063), respectively. Evaluation of CAD candidates required an additional 1.6 minutes (25th-75th percentile: 1.0 minute to 3.4 minutes). CONCLUSION The addition of CAD to reading performed by experienced readers resulted in a significant benefit in the detection of 6-9-mm polyps at CT colonography in this cohort. SUPPLEMENTAL MATERIAL http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.12120376/-/DC1.

Clinical indications for computed tomographic colonography: European Society of Gastrointestinal Endoscopy (ESGE) and European Society of Gastrointestinal and Abdominal Radiology (ESGAR) Guideline

This is an official guideline of the European Society of Gastrointestinal Endoscopy (ESGE) and the European Society of Gastrointestinal and Abdominal Radiology (ESGAR). It addresses the clinical indications for the use of computed tomographic colonography (CTC). A targeted literature search was performed to evaluate the evidence supporting the use of CTC. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) system was adopted to define the strength of recommendations and the quality of evidence. Main recommendations 1 ESGE/ESGAR recommend computed tomographic colonography (CTC) as the radiological examination of choice for the diagnosis of colorectal neoplasia. ESGE/ESGAR do not recommend barium enema in this setting (strong recommendation, high quality evidence). 2 ESGE/ESGAR recommend CTC, preferably the same or next day, if colonoscopy is incomplete. Delay of CTC should be considered following endoscopic resection. In the case of obstructing colorectal cancer, preoperative contrast-enhanced CTC may also allow location or staging of malignant lesions (strong recommendation, moderate quality evidence). 3 When endoscopy is contraindicated or not possible, ESGE/ESGAR recommend CTC as an acceptable and equally sensitive alternative for patients with symptoms suggestive of colorectal cancer (strong recommendation, high quality evidence). 4 ESGE/ESGAR recommend referral for endoscopic polypectomy in patients with at least one polyp  ≥  6  mm in diameter detected at CTC. CTC surveillance may be clinically considered if patients do not undergo polypectomy (strong recommendation, moderate quality evidence). 5 ESGE/ESGAR do not recommend CTC as a primary test for population screening or in individuals with a positive first-degree family history of colorectal cancer (CRC). However, it may be proposed as a CRC screening test on an individual basis providing the screenee is adequately informed about test characteristics, benefits, and risks (weak recommendation, moderate quality evidence).

A novel mutation in the pendrin gene associated with Pendred's syndrome

Pendreds syndrome is an autosomal recessive disorder characterized by goitre, sensorineural deafness and iodide organification defect. It is one of the most frequent causes of congenital deafness, accounting for about 10% of hereditary hearing loss. It is caused by mutations in the pendrin (PDS) gene, a 21 exon gene located on chromosome 7. The aim of this study was to examine an Italian family affected with Pendreds syndrome at the molecular level.

MR virtual endoscopy of the pancreaticobiliary tract

PURPOSE To evaluate the feasibility of surface-rendered magnetic resonance virtual endoscopy (MRVE) of magnetic resonance cholangiopancreatography (MRCP) data sets. We retrospectively reviewed MR cholangiopancreatography data sets of 120 patients with biliary stone (n=40), inflammatory ampullary stenosis (n=12), pancreatic tumor (n=8), cholangiocarcinoma (n=7), stenosis of surgical bilio-enteric anastomosis (n=4), extrinsic localized common bile duct stenosis (n=2), ampullary carcinoma (n=2), pancreatic duct stone (n=1), tumor of the gallbladder (n=1), and normal pancreaticobiliary tree (n=43). MRVE views were generated with Navigator software. Segmentation of the acquired data sets was performed with a thresholding technique. Navigation sequences were simulated through the entire biliary tract. MRVE was obtained in 27 (63%) of the 43 normal patients. Endoscopic views were generated in all 77 patients with partial or complete obstruction of the pancreaticobiliary tree. Among these, three groups of patterns were identified: 36 (47%) endoluminal masses (polyp-like masses), 17 (22%) luminal stenoses, 24 (31%) luminal occlusion. In 29 cases, hole artifacts through the internal wall were observed and interpreted as mistakes of segmentation. MRVE proved to show the internal anatomy of the biliary tract and endoluminal changes due to pathological condition. Further investigations are needed to test the usefulness and the potentialities of this technique.