ABSTRACT
This review on magnetic resonance elastography (MRE) of the breast provides an overview of available literature and describes current developments in the field of breast MRE, including new transducer technology for data acquisition and multi-frequency-derived power-law behaviour of tissue. Moreover, we discuss the future potential of breast MRE, which goes beyond its original application as an additional tool in differentiating benign from malignant breast lesions. These areas of ongoing and future research include MRE for pre-operative tumour delineation, staging, monitoring and predicting response to treatment, as well as prediction of the metastatic potential of primary tumours.
Subject(s)
Breast/diagnostic imaging , Elasticity Imaging Techniques , Magnetic Resonance Imaging , Elastic Modulus , Humans , PublicationsABSTRACT
BACKGROUND/AIMS: Lifestyle intervention is the only established therapy for non-alcoholic fatty liver disease (NAFLD). The optimal treatment schedule and predictors of response of this treatment have not been established in children. We aimed to evaluate the 2-year efficacy of an inpatient versus ambulatory intensive lifestyle intervention for treating NAFLD in children with severe obesity. METHODS: A cohort study of 51 severely obese non-diabetic children (mean age 14.7 (±2.4) years; BMI-z-score 3.5 (±0.5)) with liver steatosis were non-randomly allocated to inpatient treatment (2 or 6 months), ambulatory treatment or usual care. Proton Magnetic Resonance Spectroscopy determined liver steatosis and serum alanine aminotransferase (ALT) at 6 months were the primary outcome measures. Baseline variables were evaluated as predictors of treatment response. RESULTS: Liver steatosis had disappeared in 43, 29 and 22% and serum ALT normalized in 41, 33 and 6% at the end of 6 months in the inpatient, ambulatory or usual care treatment groups, respectively. Only the proportions of ALT normalization in inpatient and ambulatory treatment compared with usual care were significantly higher. Treatment effects of inpatient and ambulatory treatment were sustained at 1.5 years follow-up. No baseline characteristic, including PNPLA3 polymorphism or leptin, was consistently predictive for treatment response. CONCLUSIONS: A 6-month intensive inpatient and ambulatory lifestyle treatment in children with severe obesity reverses NAFLD in a minority of patients. This study suggests that inpatient compared with ambulatory intensive treatment does not importantly increase treatment success. Further efforts to optimize and individualize lifestyle interventions and additional treatments options are needed particular for children with severe obesity resistant to conventional lifestyle interventions.
Subject(s)
Ambulatory Care/methods , Behavior Therapy/methods , Hospitalization/statistics & numerical data , Non-alcoholic Fatty Liver Disease/prevention & control , Obesity, Morbid/prevention & control , Pediatric Obesity/prevention & control , Risk Reduction Behavior , Adolescent , Child , Female , Follow-Up Studies , Humans , Male , Netherlands/epidemiology , Non-alcoholic Fatty Liver Disease/epidemiology , Non-alcoholic Fatty Liver Disease/etiology , Obesity, Morbid/complications , Obesity, Morbid/epidemiology , Pediatric Obesity/complications , Pediatric Obesity/epidemiology , Treatment Outcome , Weight LossABSTRACT
WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT: Visceral fat accumulation is a risk factor for obesity-related complications. Waist circumference is used in clinical practice to assess visceral adiposity. WHAT THIS STUDY ADDS: Ultrasound is not superior to waist circumference for assessing visceral obesity in obese children. The optimal site for measuring waist circumference in obese children is at the smallest body circumference between xiphisternum and umbilicus. OBJECTIVE: Visceral fat accumulation is a well-established risk factor for obesity-related complications. In children, it has not been determined whether ultrasonography is superior to waist measurement for assessing visceral fat. Moreover, the optimal site for waist measurement has not been determined. DESIGN: In a prospective cohort of 92 severely obese children and adolescents (age 13.9 ± 2.2 years, body mass index z-score 3.29 ± 0.33), we evaluated the performance of ultrasonography and two different methods of waist circumference measurement, using magnetic resonance imaging as the reference standard. RESULTS: Waist circumference, defined as the smallest body circumference between xiphisternum and umbilicus had the strongest correlation with visceral fat quantity (r = 0.69 all, r = 0.68 girls, r = 0.64 boys). It was not outperformed by ultrasonography (r = 0.60 all, r = 0.62 girls, r = 0.50 boys) and correlated significantly better than the World Health Organization standard for waist measurement, midway between lower margin of the last rib and the crest of the ilium, (r = 0.51 all, r = 0.39 girls, r = 0.46 boys). CONCLUSIONS: Waist circumference measurement, defined as the smallest body circumference between xiphisternum and umbilicus, is the preferred non-invasive technique for daily clinical practice to assess visceral fat accumulation in severely obese children and adolescents. There is no place for ultrasonography for the quantification of visceral fat in this group.