Cyrielle Caussy1, Justine Brissot2, Seema Singh2, Shirin Bassirian2, Carolyn Hernandez2, Ricki Bettencourt2, Emily Rizo2, Lisa Richards2, Claude B Sirlin3, Rohit Loomba4. 1. NAFLD Research Center, Department of Medicine, University of California, San Diego, La Jolla, California; CarMen Laboratory, INSERM U1060, INRA U1397, Université Claude Bernard Lyon 1, National Institute of Applied Sciences of Lyon, Pierre-Bénite, France; Département Endocrinologie, Diabète et Nutrition, Hôpital Lyon Sud, Hospices Civils de Lyon, Pierre-Bénite, France. 2. NAFLD Research Center, Department of Medicine, University of California, San Diego, La Jolla, California. 3. Liver Imaging Group, Department of Radiology, University of California, San Diego, La Jolla, California. 4. NAFLD Research Center, Department of Medicine, University of California, San Diego, La Jolla, California; Division of Gastroenterology, Department of Medicine, University of California, San Diego, La Jolla, California; Division of Epidemiology, Department of Family and Preventive Medicine, University of California at San Diego, La Jolla, California. Electronic address: roloomba@ucsd.edu.
Abstract
BACKGROUND & AIMS: Controlled attenuation parameter (CAP) measurements using M probe have been reported to be lower than those of the XL-probe in detection of hepatic steatosis. However, there has been no direct comparison of CAP with the M vs the XL probe in patients with nonalcoholic fatty liver disease (NAFLD). We compared CAP with the M vs the XL probe for quantification of hepatic fat content, using magnetic resonance imaging proton density fat fraction (MRI-PDFF) as the standard. METHODS: We performed a prospective study of 100 adults (mean body mass index [BMI], 30.6 ± 4.7 kg/m2) with and without NAFLD, assessed by CAP with the M probe and XL probe on the same day, at a single research center, from November 2017 through November 2018. We then measured the MRI-PDFF as the reference standard. Outcomes were presence of hepatic steatosis, defined as MRI-PDFF ≥ 5%, and detection of hepatic fat content ≥ 10%, defined as MRI-PDFF ≥ 10%. We performed area under the receiver operating characteristic curve (AUROC) analyses to assess the diagnostic accuracy of CAP for each probe in detection of hepatic steatosis (MRI-PDFF ≥ 5%) and of hepatic fat content ≥ 10%. RESULTS: Of the study participants, 68% had an MRI-PDFF of 5% or more and 48% had an MRI-PDFF of 10% or more. The mean CAP measured by the M probe (310 ± 62 db/m) was significantly lower than by the X probe (317 ± 63 db/m) (P = .007). When M probe was used in participants with BMIs <30 kg/m2 and XL probe in participants with BMIs ≥30 kg/m2, the CAP measured by the M probe (312 ± 51.4 db/m) remained significantly lower than that of the XL probe (345 ± 47.6 db/m) (P = .0035.), when the MRI-PDFF was above 5%. The optimal threshold of CAP for the detection of MRI-PDFF≥5%, was 294 db/m with the M probe and 307 db/m with the XL probe. The optimal threshold of CAP for the detection of MRI-PDFF ≥ 10%, was 311 db/m with the M probe and 322 db/m with the XL probe. For only the XL probe, CAP measurements with an interquartile range below 30 dB/m detected an MRI-PDFF≥5% with a lower AUROC (0.97; 95% CI, 0.80-1.00) than CAP measurements with an interquartile range above 30 dB/m (AUROC, 0.82; 95% CI, 0.71-0.90) (P = .0129). CONCLUSIONS: In an analysis of the same patients using CAP with the M probe and XL probe, with MRI-PDFF as the standard, we found that the M probe under-quantifies CAP values compared with the XL probe, independent of BMI. The type of probe should be considered when interpreting CAP data from patients with NAFLD.
BACKGROUND & AIMS: Controlled attenuation parameter (CAP) measurements using M probe have been reported to be lower than those of the XL-probe in detection of hepatic steatosis. However, there has been no direct comparison of CAP with the M vs the XL probe in patients with nonalcoholic fatty liver disease (NAFLD). We compared CAP with the M vs the XL probe for quantification of hepatic fat content, using magnetic resonance imaging proton density fat fraction (MRI-PDFF) as the standard. METHODS: We performed a prospective study of 100 adults (mean body mass index [BMI], 30.6 ± 4.7 kg/m2) with and without NAFLD, assessed by CAP with the M probe and XL probe on the same day, at a single research center, from November 2017 through November 2018. We then measured the MRI-PDFF as the reference standard. Outcomes were presence of hepatic steatosis, defined as MRI-PDFF ≥ 5%, and detection of hepatic fat content ≥ 10%, defined as MRI-PDFF ≥ 10%. We performed area under the receiver operating characteristic curve (AUROC) analyses to assess the diagnostic accuracy of CAP for each probe in detection of hepatic steatosis (MRI-PDFF ≥ 5%) and of hepatic fat content ≥ 10%. RESULTS: Of the study participants, 68% had an MRI-PDFF of 5% or more and 48% had an MRI-PDFF of 10% or more. The mean CAP measured by the M probe (310 ± 62 db/m) was significantly lower than by the X probe (317 ± 63 db/m) (P = .007). When M probe was used in participants with BMIs <30 kg/m2 and XL probe in participants with BMIs ≥30 kg/m2, the CAP measured by the M probe (312 ± 51.4 db/m) remained significantly lower than that of the XL probe (345 ± 47.6 db/m) (P = .0035.), when the MRI-PDFF was above 5%. The optimal threshold of CAP for the detection of MRI-PDFF≥5%, was 294 db/m with the M probe and 307 db/m with the XL probe. The optimal threshold of CAP for the detection of MRI-PDFF ≥ 10%, was 311 db/m with the M probe and 322 db/m with the XL probe. For only the XL probe, CAP measurements with an interquartile range below 30 dB/m detected an MRI-PDFF≥5% with a lower AUROC (0.97; 95% CI, 0.80-1.00) than CAP measurements with an interquartile range above 30 dB/m (AUROC, 0.82; 95% CI, 0.71-0.90) (P = .0129). CONCLUSIONS: In an analysis of the same patients using CAP with the M probe and XL probe, with MRI-PDFF as the standard, we found that the M probe under-quantifies CAP values compared with the XL probe, independent of BMI. The type of probe should be considered when interpreting CAP data from patients with NAFLD.
Authors: Daniella Braz Parente; Hugo Perazzo; Fernando Fernandes Paiva; Carlos Frederico Ferreira Campos; Carlos José Saboya; Silvia Elaine Pereira; Felipe d'Almeida E Silva; Rosana Souza Rodrigues; Renata de Mello Perez Journal: Sci Rep Date: 2020-09-14 Impact factor: 4.379