Measurement of vertebral foraminal dimensions using three-dimensional computerized tomography

Area of Science:

• Anatomy
• Radiology
• Medical Imaging

Background:

• Accurate measurement of lumbar intervertebral foramina is crucial for diagnosing spinal stenosis and planning surgical interventions.
• Three-dimensional computerized tomography (3D-CT) is a common imaging modality, but its accuracy in measuring foraminal dimensions requires validation.

Purpose of the Study:

• To evaluate the accuracy of 3D-CT in measuring lumbar intervertebral foramina dimensions.
• To compare 3D-CT measurements with direct cadaveric measurements.
• To identify optimal 3D-CT imaging protocols for foraminal assessment.

Main Methods:

• Lumbar intervertebral foramina in cadaveric spines were measured using 3D-CT with six different reconstruction protocols.
• Measurements were compared to direct caliper measurements obtained after dissection.
• Image quality and agreement between methods were assessed.

Main Results:

• All 3D-CT measurements consistently underestimated the true dimensions of the lumbar intervertebral foramina.
• The best agreement and image quality were achieved using 4/3 slices and a 300 Hounsfield Unit reconstruction threshold.
• Despite optimization, 3D-CT measurements showed significant discrepancies with direct measurements.

Conclusions:

• 3D-CT is not recommended for precise quantitative measurement of lumbar intervertebral foramina dimensions.
• However, 3D-CT may still be valuable for qualitative assessment and surgical planning of spinal procedures.
• Further research may refine 3D-CT protocols for improved accuracy in foraminal dimension assessment.