Accuracy of cone-beam computed tomography for syndesmosis injury diagnosis compared to conventional computed tomography.

BACKGROUND: Syndesmosis injury can lead to ankle mortise instability and early osteoarthritis. Several multiple detector computed tomography (MDCT) methods for measurement have been developed. Weight-bearing cone beam CT (WB CBCT) is an emerging technique that offers the possibility of upright-position scanning and lower doses. This study sought to assess the diagnostic accuracy of WB CBCT in syndesmose injury compared to MDCT, with instability confirmed via manual testing upon arthroscopic examination. METHODS: Three musculoskeletal radiologists with different levels of expertise prospectively analyzed 11 MDCT and eight WB CBCT scans of the same trauma-afflicted ankles with clinical suspicion of syndesmosis lesion over a period of 5 months. They evaluated 10 methods of measurement in both sides. Syndesmosis was considered pathological on arthroscopic examination in four patients. Correlation between readers was evaluated with intra-class correlation testing (p < 0.05 was considered significant). Capacity of discrimination was assessed by area under the curve (AUC) for all methods. RESULTS: Inter-observer agreement was near excellent for both WB CBCT and MDCT for the anterior tibio-fibular (TF) distance (ICC = 0.781 and 0.831, respectively), posterior TF distance (ICC = 0.841 and 0.826), minimal TF distance (ICC = 0.899 and 0.875), and TF surface (ICC = 0.93 and 0.84). AUC were better for MDCT than WB CBCT in assessing syndesmosis instability for: anterior TF distance (ROC = 0.869 vs. 0.555, p = 0.01), minimal TF distance (ROC = 0.883 vs. 0.608, p = 0.02) and antero-posterior fibular translation (ROC = 0.894 vs. 0.467, p = 0.006). CONCLUSIONS: MDCT demonstrated better ability to distinguish pathological syndesmosis than WB CBCT, with the antero-posterior fibular translation the best discriminating measurement. The physiological widening of the contralateral syndesmosis occurring with the WB CBCT upright position may explain these results.

What is the diagnostic performance of 18-FDG-PET/MR compared to PET/CT for the N- and M- staging of breast cancer?

PURPOSE: To compare the diagnostic performance of 18-FDG-PET/MR and PET/CT for the N- and M- staging of breast cancer. METHODS AND MATERIALS: Two independent readers blinded to clinical/follow-up data reviewed PET/MR and PET/CT examinations performed for initial or recurrent breast cancer staging in 80 consecutive patients (mean age = 48 ± 12.9 years). The diagnostic confidence for lesions in the contralateral breast, axillary/internal mammary nodes, bones and other distant sites were recorded. Sensitivity, specificity, positive (PPV) and negative predictive values (NPV) were calculated. The standard of reference included pathology and/or follow-up > 12 months. RESULTS: Nine of 80 patients had bone metastases; 13/80 had other distant metastases, 44/80 had axillary, 9/80 had internal mammary and 3/80 had contralateral breast tumours. Inter-reader agreement for lesions was excellent (weighted kappa = 0.833 for PET/CT and 0.823 for PET/MR) with similar reader confidence for the two tests (ICC = 0.875). In the patient-per-patient analysis, sensitivity and specificity of PET/MRI and PET/CT were similar (p > 0.05). In the lesion-per-lesion analysis, the sensitivity of PET/MR and PET/CT for bone metastases, other metastases, axillary and internal mammary nodes, contralateral tumours and all lesions together was 0.924 and 0.6923 (p = 0.0034), 0.923 and 0.923 (p = 1), 0.854 and 0.812 (p = 0.157), 0.9 and 0.9 (p = 1), 1 and 0.25 (p = 0.083), and 0.89 and 0.77 (p = 0.0013) respectively. The corresponding specificity was 0.953 and 1 (p = 0.0081), 1 and 1 (p = 1), 0.893 and 0.92 (p = 0.257), 1 and 1 (p = 1), 0.987 and 0.99 (p = 1) and 0.96 and 0.98 (p = 0.0075) respectively. CONCLUSIONS: Reader confidence, inter-reader agreement and diagnostic performance per patient were similar with PET/MR and PET/CT. However, for all lesions together, PET/MR had a superior sensitivity and lower specificity in the lesion-per-lesion analysis. KEY POINTS: • N and M breast cancer staging performance of PET/MR and PET/CT is similar per patient. • In a lesion-per-lesion analysis PET/MR is more sensitive than PET/CT especially for bone metastasis. • Readers' diagnostic confidence is similar for both tests.

Routine chest X-ray is not mandatory after fluoroscopy-guided totally implantable venous access device insertion.

BACKGROUND: The aim of this study is to determine whether systematic postoperative chest X-ray is required after totally implantable venous access port device (TIVAD) placement under fluoroscopic control. METHODS: A retrospective chart review of all consecutive patients with fluoroscopy-guided TIVAD insertion from July 10, 2009 to April 16, 2012 was conducted at the Geneva University Hospitals (n = 927). Patients with an available postoperative chest X-ray were included, regardless of approach (open or percutaneous) and venous access site (subclavian, cephalic, jugular, etc.). Exclusion criteria were incomplete data and preexisting pneumothorax or hemothorax. RESULTS: Eight hundred ninety-one patients were included. First-intention venous cutdown was performed in 878 patients (98.5%), with success rates of 79.4% and 88.2% when targeting the left and right cephalic veins, respectively. Percutaneous access was the chosen first-intention procedure for 12 patients (1.3%). Eight-hundred thirty-six (93.8%) insertions were performed only by the open approach and 53 (5.9%) implantations required at least one venous puncture. Two implantations were performed using previous central venous accesses. Immediate complications associated with TIVAD placement and detected on the postoperative chest X-ray consisted of 1 asymptomatic pneumothorax, 1 symptomatic hemothorax, and 2 malpositions of the catheter. One additional pneumothorax was discovered during the first night after TIVAD insertion in a patient who became symptomatic. CONCLUSIONS: The very low incidence of immediate complications detected by postprocedural chest X-ray suggests that such a control is not mandatory as a routine method after fluoroscopy-guided TIVAD insertion mainly performed by venous cutdown. X-ray should be performed only in cases of clinical suspicion.

Metallic artifact reduction by evaluation of the additional value of iterative reconstruction algorithms in hip prosthesis computed tomography imaging.

To evaluate iterative metal artifact reduction (iMAR) technique in images data of hip prosthesis on computed tomography (CT) and the added value of advanced modeled iterative reconstruction (ADMIRE) compared with standard filtered back projection (FBP).Twenty-eight patients addressed to CT examinations for hip prosthesis were included prospectively. Images were reconstructed with iMAR algorithm in addition to FBP and ADMIRE techniques. Measuring image noise assessed objective image quality and attenuation values with standardized region of interest (ROI) in 4 predefined anatomical structures (gluteus medius and rectus femoris muscles, inferior and anterior abdominal fat, and femoral vessels when contrast media was present). Subjective image quality was graded on a 5-point Likert scale, taking into account the size of artifacts, the metal-bone interface and the conspicuity of pelvic organs, and the diagnostic confidence.Improvement in overall image quality was statistically significant using iMAR (P<.001) compared with ADMIRE and FBP. ADMIRE did not show any impact in image noise, attenuation value, or global quality image. iMAR showed a significant decrease in image noise in all ROIs (Hounsfield Unit) as compared with FBP and ADMIRE. Interobserver agreement was high in all reconstructions (FBP, FBP+iMAR, ADMIRE, and ADMIRE + iMAR) more than 0.8. iMAR reconstructions showed emergence of new artifacts in bone-metal interface.iMAR algorithm allows a significant reduction of metal artifacts on CT images with unilateral or bilateral prostheses without additional value of ADMIRE. It improves the analysis of surrounding tissue but potentially generates new artifacts in bone-metal interface.

Combination of Adenomyoma and Adenomyomatous Hyperplasia of the Ampullary System: A First Case Report.

Adenomyoma and adenomyomatous hyperplasia are benign tumor-like lesions that rarely involve the major or minor duodenal papilla. We report the case of a 73-year-old patient who underwent a cephalic duodenopancreatectomy due to clinical and radiological evidence of underlying malignant neoplasm. The histopathology results revealed the unusual association of a major duodenal papilla adenomyoma and an adenomyomatous hyperplasia of the minor papilla. Because of their resemblance to pancreatic malignancy, the diagnosis of these lesions is particularly challenging. In most cases, it is established postoperatively, after histopathological examination of the surgical specimen.

Feasibility of synthetic MRI in knee imaging in routine practice.

BACKGROUND: Synthetic magnetic resonance (MR) is a method allowing reduction of examination time and access to quantitative imaging. PURPOSE: This study sought to assess the image quality and diagnostic accuracy of synthetic magnetic resonance imaging (MRI) compared to standard MRI in patients with knee pain. MATERIAL AND METHODS: In total, 22 patients underwent standard 1.5 knee MRI with an added synthetic sequence. Quantitative T1, T2, and proton density (PD) images were generated synthetically; T1, PD, and short tau inversion recovery (STIR) weighted images were created with chosen echo time (TE), repetition time (TR), and inversion time (TI). Two blinded musculoskeletal radiologists evaluated the overall sequence quality, visualization of anatomic structures, and presence of artifacts using a 3-point score. RESULTS: The synthetic sequence was acquired in 39% less time than the conventional MRI. Synthetic PD, T1, and STIR images were rated fair (2%, 5%, and 2%, respectively) or good quality (98%, 95%, and 98%, respectively), despite the presence of popliteal artery artifacts. Cartilage and meniscus were well visualized in all cases. Anterior cruciate ligament visualization was rated poor in 7%, 14%, and 30% of PD, STIR, and T1 images, respectively. CONCLUSION: Our pilot study confirmed the feasibility of synthetic MRI in knee examinations, proving faster and achieving appropriate quality and good diagnostic confidence.