Area of interest | Definition |
TAP | The fascial plane between the transversus abdominis and internal oblique muscles |
Posterior QL | The fascial plane between the posterior aspect of the QL muscle and the middle layer of the thoracolumbar fascia |
Anterior QL | The fascial plane between the anterior aspect of the QL and psoas muscle |
Intercostal plane | The fascial plane along the inferior border of the ribs |
Lumbar paravertebral space | Presence of injectate between the transverse processes and the psoas muscle in the proximity of the lumbar intervertebral foramen |
Lumbar nerve roots | Presence of injectate in contact with the nerve roots or within the psoas compartment |
Sympathetic chain | Presence of injectate on the lateral side of a vertebral body |
Thoracic paravertebral space | Presence of injectate at or cranial to T12 in the thoracic paravertebral space |
QL, quadratus lumborum; TAP, transversus abdominis plane.