Pediatric Hepatoblastoma After Neoadjuvant Chemotherapy: Diagnostic Performance of MR in Staging POSTTEXT and Vascular Involvement.

BACKGROUND: The assessment of resectability after neoadjuvant chemotherapy of hepatoblastoma is dependent on Post-Treatment EXTENT of Disease (POSTTEXT) staging and its annotation factors P (portal venous involvement) and V (hepatic venous/inferior vena cava [IVC] involvement), but MR performance in assessing them remains unclear. PURPOSE: To assess the diagnostic performance of contrast-enhanced MR imaging for preoperative POSTTEXT staging and diagnosing vascular involvement in terms of annotation factors P and V in pediatric hepatoblastoma following neoadjuvant chemotherapy. STUDY TYPE: Retrospective. SUBJECTS: Thirty-five consecutive patients (17 males, median age, 24 months; age range, 6-98 months) with proven hepatoblastoma underwent preoperative MR imaging following neoadjuvant chemotherapy. FIELD STRENGTH/SEQUENCE: 3.0 T; T2-weighted imaging (T2WI), T2WI with fat suppression, diffusion weighted imaging, radial stack-of-the-star/Cartesian 3D Dixon T1-weighted gradient echo imaging. ASSESSMENT: Three radiologists independently assessed the POSTTEXT stages and annotation factors P and V based on the 2017 PRE/POSTTEXT system. The sensitivities and specificities were calculated for 1) diagnosing each POSTTEXT stage; 2) discrimination of stages III and IV (advanced) from those stages I and II (non-advanced) hepatoblastomas; and 3) annotation factors P and V. The combination of pathologic findings and surgical records served as the reference standard. STATISTICAL TESTS: Sensitivity, specificity, Fleiss kappa test. RESULTS: The sensitivity and specificity ranges for discriminating advanced from non-advanced hepatoblastomas were 73.3%-80.0% and 80.0%-90.0%, respectively. For annotation factor P, they were 66.7%-100.0% and 90.6%, respectively. For factor V, they were 75.0% and 67.7%-83.9%, respectively. There was excellent, substantial, and moderate agreement on POSTTEXT staging (Fleiss kappa = 0.82), factors P (Fleiss kappa = 0.64), and factors V (Fleiss kappa = 0.60), respectively. DATA CONCLUSION: MR POSTTEXT provides reliable discrimination between advanced and non-advanced tumors, and MR has moderate to excellent specificity at identifying portal venous and hepatic venous/IVC involvement. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 3.

Creeping fat in patients with ileo-colonic Crohn's disease correlates with disease activity and severity of inflammation: A preliminary study using energy spectral computed tomography.

OBJECTIVE: To investigate the relationship between creeping fat and inflammatory activity as well as the prognosis of ileo-colonic Crohn's disease (CD), based on a quantitative analysis of energy spectral computed tomography (CT). METHODS: A total of 40 patients with CD and 40 with other gastrointestinal diseases who underwent an energy spectral CT scanning between March 2014 and March 2015 were retrospectively enrolled. The endoscopic severity of CD was evaluated by the simple endoscopic score for Crohn's disease (SES-CD). The slope of the Hounsfield unit (HU) curve (λHU ) was measured and calculated on energy spectral CT images. Visceral and subcutaneous fat areas were also measured. The relationship between the quantitative data of creeping fat as well as the fat area and CD inflammation were analyzed. RESULTS: The λHU of creeping fat in patients with CD increased with the severity of intestinal inflammation (moderate/severe vs mild: -0.17 ± -0.68 vs -0.49 ± -0.61, P < 0.01). Moreover, the λHU of creeping fat around the intestinal segments without lesions in CD was significantly larger than that in the controls (-1.19 ± -0.56 vs - 1.42 ± -0.45, P < 0.01). The λHU was more accurate for detecting inflammatory lesions in CD than for calculating visceral fat. It was significantly correlated with SES-CD (r = 0.66, P < 0.01) and moderately correlated with the Harvey-Bradshaw index (r = 0.414, P < 0.01). CONCLUSION: The quantitative analysis of creeping fat using energy spectral CT is an effective method in inflammatory evaluation in patients with CD.

Optimal b value of diffusion-weighted imaging on a 3.0T magnetic resonance scanner in Crohn's disease.

AIM: To determine the optimal b value of diffusion-weighted imaging for detecting active inflammation in Crohn's disease. METHODS: Thirty-one patients clinically diagnosed with active Crohn's disease were referred for magnetic resonance examination. All patients were scanned on a 3.0T magnetic resonance scanner using the same protocol involving four different b values (800, 1500, 2000 and 2500 s/mm(2)). The diagnostic effect of diffusion-weighted imaging was evaluated and compared with endoscopic findings. The diffusion-weighted image quality of four b value groups was evaluated and apparent diffusion coefficient was measured for both normal and inflammatory intestinal segments. RESULTS: The contrast-to-noise ratio and signal-to-noise ratio were not satisfied when b value 2000 or 2500 s/mm(2) was adopted (36.52 ± 14.95 vs 34.78 ± 24.83, P > 0.05; 53.58 ± 23.45 vs 47.58 ± 29.67, P > 0.05). The qualitative image quality was not enough to meet diagnostic requirement. No matter which b value was chosen, the apparent diffusion coefficient of inflammatory intestinal segments was significantly lower than that of normal intestinal segments (1.38 ± 0.28 vs 2.00 ± 0.38, P < 0.01; 1.09 ± 0.20 vs 1.50 ± 0.28, P < 0.01; 0.95 ± 0.19 vs 1.34 ± 0.28, P < 0.01; 0.88 ± 0.14 vs 1.20 ± 0.21, P < 0.01). The lesion detection rate (90.32%), diagnostic sensitivity (81.18%) and specificity (95.10%) would be appropriate when b value 1500 s/mm(2) was adopted. CONCLUSION: High b value is suitable for intestinal DW examination on a high field MR scanner.

T staging of rectal cancer: accuracy of diffusion-weighted imaging compared with T2-weighted imaging on 3.0 tesla MRI.

OBJECTIVE: To evaluate the performance of diffusion-weighted imaging (DWI) in the T staging of primary rectal cancer compared with T2-weighted (T2W) fast spin-echo imaging using 3.0 tesla magnetic resonance imaging (MRI). METHODS: In total, 46 consecutive patients with rectal cancer who underwent MRI examination before surgery were included in the study. The diagnostic accuracy, sensitivity and specificity of DWI and T2W imaging (T2WI) for T staging of the tumors were evaluated, and interobserver agreement between the two radiologists was calculated. RESULTS: The diagnostic accuracies of DWI and T2WI for the T staging of rectal cancer were 73.9% and 71.7%, respectively. The sensitivity and specificity of DWI were 90.0% and 88.9% for diagnosing T1 tumors, 64.3% and 87.5% for T2 tumors, 77.8% and 89.3% for T3 tumors and 50.0% and 97.6% for T4 tumors, respectively; while the sensitivity and specificity of T2WI were 80.0% and 91.7% for T1 tumors, 64.3% and 78.1% for T2 tumors, 77.8% and 89.3% for T3 tumors and 50.0% and 100% for T4 tumors, respectively. There were no significant differences in the diagnostic accuracy, sensitivity or specificity between DWI and T2WI no matter what kind of T stage was concerned (P > 0.05). The interobserver agreement was 0.74 for DWI and 0.63 for T2WI. CONCLUSIONS: DWI can be applied as a useful tool for evaluating the T staging of rectal cancer. The interobserver agreement obtained by using DWI is better than that obtained by using T2WI.

[The effect of anticoagulant thrombolytic therapy on acute deep venous thrombosis prognosis].

OBJECTIVE: To explore the effect of anticoagulant thrombolytic therapy on acute deep venous thrombosis (DVT) and the incidence and severity of post-thrombotic syndrome (PTS). METHOD: A total of 111 patients (113 limbs) with central or mixed types of deep venous thrombosis admitted from March 2003 to November 2008 were analyzed. The patients were divided into 3 groups by different therapies: anticoagulant group (41 limbs), thrombolysis group (27 limbs), and catheter-directed thrombolysis group (45 limbs). In the follow-up, patients' swelling of lower extremity and recanalization of vein were found out by physical examination and venous ultrasound Duplex through following-up. The Villalta and VCSS marking scales were used in rating the incidence and severity of PTS, discussing treatments for acute phase as well as adjuvant treatment for chronic phase and the correlation between the incidence and severity of PTS. RESULTS: The average time of follow-up were (41 ± 19) months in anticoagulant group, (52 ± 11) months in thrombolysis group, and (26 ± 10) months in catheter-directed thrombolysis group. According to the consequences from Villalta and VCSS rating scales, the incidences of PTS in the three groups were 58.5% (24/41), 55.6% (15/27), and 35.6% (16/45), in which 20.8% (5/24), 3/15, and 1/16 were severe. The the catheter-directed thrombolysis group had a better consequence than the other two groups in reducing incidence and severity of PTS (P < 0.05). The differences of circumferences of lower extremities of all patients had obvious improvement compared to that before the treatments. For patients who were treated by catheter-directed thrombolysis, the thigh circumference difference and calf circumference difference were (0.5 ± 1.0) cm and (0.7 ± 1.0) cm, which were more obvious compared to other two groups (P < 0.05). Most patients had their external-iliac and common-femoral veins recanalized. Using anticoagulant pharmaceuticals and compression stockings can lead to a reduction in the incidence of PTS. CONCLUSIONS: The incidences and symptoms of PTS and swelling of limbs can be significantly moderated by catheter-directed thrombolysis based on anticoagulating in the acute phase of DVT. Consequently, it would be the most efficient way in decreasing the occurrences of PTS and moderating the severities of PTS with the aids of regular anticoagulating and compression stockings.