Normal Hologic Spine Scan
This image shows a normal Hologic spine scan.
The patient should be in the center of the table with approximately equal amounts of soft tissue on each side.
An upper vertebra with ribs and the iliac rest should be included in the scan to help with determination of vertebral leves.
Case Description:
This is a normal Hologic spine scan.
The patient should be in the middle of the scanner bed. The knees are positioned up on a block so that the back is flattened out on the table. Most blocks have different dimensions, and the height of knees elevation depends upon the height of the patient. Include a part of the thoracic spine with a vertebra with ribs and the upper part of the pelvis so that the iliac crest is visible. The iliac crest designates the L4-L5 interspace. The International Society for Clinical Densitometry (ISCD) convention is to number vertebral bodies from the bottom upwards, in this way the labelling of vertebral bodies remains the same on follow-up scans. On this scan L5 has a characteristic dog bone or I shape.
The spine is straight on the table and is parallel to the sides of the image. The spine is centered in the scan field, with roughly equal amounts of soft tissue on both sides. This won’t always be possible, especially with individuals with degenerative changes in their spine.
The default width of the spine analysis on a Hologic scanner is 116 pixels wide.
It should be checked that the edge detection outlines the bony edges and that the intervertebral markers are in approximately the center of the intervertebral space.
Things to evaluate on a scan include: PARED
P – Positioning – is the patient positioned correctly
A – Artifacts – Are there artifacts in the soft tissue or over bone?
R – Region of Interest – are the regions of interest correct?
E – Edge Detection – Is the edge detection algorithm correct?
D – Databases – Are the correct databases used for the T-scores and Z-scores?
Credit:
Sarah L Morgan, MD, RD, CCD, The University of Alabama at Birmingham