Details

Autor(en) / Beteiligte

• Rollins, Katie E
• Javanmard-Emamghissi, Hannah
• Awwad, Amir
• Macdonald, Ian A
• Fearon, Kenneth C.H
• Lobo, Dileep N., Professor

Titel

Body composition measurement using computed tomography: does the phase of the scan matter?

Ist Teil von

• Nutrition (Burbank, Los Angeles County, Calif.), 2017-09, Vol.41, p.37-44

Ort / Verlag

United States: Elsevier Inc

Erscheinungsjahr

2017

Link zum Volltext

Quelle

MEDLINE

Beschreibungen/Notizen

• Abstract Background and Aims We aimed to determine, from the methodological standpoint, the effect of the presence or absence of intravenous contrast on body composition variables obtained by analysis of computed tomography (CT) images. Methods Tri-phasic abdominal (non-contrast, arterial phase and portovenous phase contrast) CT scans from 111 patients were analysed by two independent assessors at the third lumbar vertebral level using SliceOmatic software (version 5.0, TomoVision, Montreal, Canada). Variables included skeletal muscle index (SMI), fat and fat free mass (FM and FFM, respectively) and mean skeletal muscle Hounsfield units (SMHU). Results Mean SMHU was lowest in the non-contrast phase (29.4, SD 8.9 HU), followed by arterial (32.4, SD 9.3 HU) then portovenous phases (34.9, SD 9.4 HU). The mean skeletal muscle attenuation was significantly different dependent upon the phase of the scan in which the images were obtained. Calculated FM was significantly lower in both arterial (28.6, SD 8.8 kg, p<0.0001) and portovenous phase scans (28.5, SD 8.9 kg, p<0.0001) when compared with non-contrast (29.2, SD 8.9 kg). The mean FFM was not significantly different as measured on non-contrast, arterial or portovenous phase CT scans (48.0, SD 11.2, 48.1, SD 9.8, and 48.6, SD 10.2 kg, respectively). No difference was seen in SMI. Inter-observer reliability was high. Conclusions The definition of myosteatosis should include a standardised phase of CT for analysis and this should be incorporated within its definition. However, as the magnitudes of the differences were relatively small, the impact of the phase of the scan on predicting outcome needs to be determined.