Reproducibility of T1ρ and T2 quantification in a multi-vendor multi-site study.

OBJECTIVE: To evaluate the multi-vendor multi-site reproducibility of two-dimensional (2D) multi-echo spin-echo (MESE) T2 mapping (product sequences); and to evaluate the longitudinal reproducibility of three-dimensional (3D) magnetization-prepared angle-modulated partitioned k-space spoiled gradient echo snapshots (MAPSS) T1ρ and T2 mapping (research sequences), and 2D MESE T2 mapping, separated by 6 months, in a multi-vendor multi-site setting. METHODS: Phantoms and volunteers (n = 5 from each site, n = 20 in total) were scanned on four 3 T magnetic resonance (MR) systems from four sites and three vendors (Siemens, General Electric, and Phillips). Two traveling volunteers (3 knees) scanned at all 4 sites at baseline and 6-month follow-up. Data was transferred to one site for centralized processing. Coefficients of variation (CVs) were calculated to evaluate reproducibility. RESULTS: For baseline 2D MESE T2 measures, average CV were 0.37-2.45% (intra-site) and 5.96% (inter-site) for phantoms, and 3.15-8.49% (intra-site) and 14.16% (inter-site) for volunteers. For longitudinal phantom data, intra-site CVs were 1.42-3.48% for 3D MAPSS T1ρ, 1.77-3.56% for 3D MAPSS T2, and 1.02-2.54% for 2D MESE T2. For the longitudinal volunteer data, the intra-site CVs were 2.60-4.86% for 3D MAPSS T1ρ, 3.33-7.25% for 3D MAPSS T2, and 3.11-8.77% for 2D MESE T2. CONCLUSION: This study demonstrated excellent intra-site reproducibility of 2D MESE T2 imaging, while its inter-site variation was slightly higher than 3D MAPSS T2 imaging (10.06% as previously reported). This study also showed excellent reproducibility of longitudinal T1ρ and T2 cartilage quantification, in a multi-vendor multi-site setting for both product 2D MESE T2 and 3D MAPSS T1p/T2 research sequences.

Outcomes of a conservative approach to management in amoebic liver abscess.

CONTEXT: Unfortunately, there is confusion among the medical community regarding the management of amoebic liver abscess (ALA). Therapeutic options range from simple pharmacotherapy to use of interventions like a needle or catheter aspiration under ultrasound guidance to surgical intervention. There is a plethora of thresholds for parameters such as the maximum diameter of the abscess and volume on ultrasound examination suggested by various authors to serve as a criterion to help to decide when to use which modality in these cases. AIMS: To assess the outcome of patients with uncomplicated ALA treated using a conservative approach. Moreover, to identify factors associated with its failure. SETTINGS AND DESIGN: A prospective, observational study was carried out at a large municipal urban health care center over a period of 3-year (2011-2014) in India. MATERIALS AND METHODS: Patients with uncomplicated ALA were recruited. All patients were managed with pharmacotherapy initially for a period of 72 h. Response to treatment was assessed by resolution of symptoms within the given time frame. Failure to respond was considered an indication for intervention. Needle aspiration was offered to these patients and response assessed within 72 h. Failure to respond to aspiration was considered an indication for catheter drainage. STATISTICAL ANALYSIS USED: Data recorded were entered in a Microsoft Office Excel Sheet and analyzed using the SPSS version 16.0 (IBM). RESULTS: Sixty patients with ALA were included in the study over its duration. Forty-nine (81.67%) patients were managed conservatively, while 11 (18.33%) patients needed an intervention for relief. Patients who required intervention had deranged liver function at presentation, a larger abscess diameter (10.09 ± 2.23 vs. 6.33 ± 1.69 cm P < 0.001) and volume (399.73 ± 244.46 vs. 138.34 ± 117.85 ml, P < 0.001) compared to those who did not need it. Patients that required intervention had a longer length of hospital stay (7.1 ± 2.4 vs. 4.8 ± 0.9 days, P < 0.001). On post hoc analysis, a maximum diameter of >7.7 cm was found to be the optimal criterion to predict the need of intervention in cases of ALA. CONCLUSIONS: A conservative approach is effective in the management of ALA for a majority of patients. Failure of conservative management was predicted by the size of the abscess (maximum diameter >7.7 cm). Even in the cases of failure, a gradual step-up with interventions was found to be safe and effective.

Measles surveys.

The authors present background data indicating that there is a close correlation between serological findings and children's measles histories obtained from parents. They conclude that interrogative surveys can yield reliable epidemiological information even though the sample of the survey population checked serologically may be small.