Facilitating cartilage volume measurement using MRI

Purpose: To compare quantitative cartilage volume measurement (CVM) using different slice thicknesses.

Materials and methods: Ten knees were scanned with a 1.5T MRI (Sonata, Siemens, Erlangen, Germany) using a 3D gradient echo sequence (FLASH, fast low-angle shot). Cartilage volume of the medial and lateral tibial plateau was measured by two independent readers in 1.5mm, 3.0mm and 5.0mm slices using the Argus software application. Accuracy and time effectiveness served as control parameters.

Results: Determining cartilage volume, time for calculation diminished for the lateral tibial plateau from 384.6+/-127.7s and 379.1+/-117.6s to 214.9+/-109.9s and 213.9+/-102.2s to 122.1+/-60.1s and 126.8+/-56.2s and for the medial tibial plateau from 465.0+/-147.7s and 461.8+/-142.7s to 214.0+/-67.9s and 208.9+/-66.2s to 132.6+/-41.5s and 130.6+/-42.0s measuring 1.5mm, 3mm and 5mm slices, respectively. No statistically significant difference between cartilage volume measurements was observed (p>0.05) while very good inter-reader correlation was evaluated.

Conclusion: CVM using 1.5mm slices provides no higher accuracy than cartilage volume measurement in 5mm slices while an overall time saving up to 70% is possible.