Table 1 Definitions of compartments and tissue.
Compartment | Thresholds | Tissue | |
|---|---|---|---|
Label | Definition | HU | Label |
Muscle | Regions predominantly including muscles, without separating individual muscles. Includes smaller vessels and inter- and intramuscular connective tissues | − 29 to 150 | Total skeletal muscle tissue (SMtotal) |
Iliopsoas Muscle | Subset of muscle compartment, including only iliopsoas muscle | − 29 to 150 | Psoas skeletal muscle tissue (SMpsoas) |
Visceral | Regions beneath the thoracic cage and muscles of the abdominal wall. Includes pelvis and retroperitoneum. Excludes solid organs and larger vessels | − 190 to − 30 | Visceral adipose tissue (VAT) |
Subcutaneous | Regions beneath the skin, overlaying fascias or periosteum. Excludes foreign material (e.g., implants) | − 190 to − 30 | Subcutaneous adipose tissue (SAT) |
