Evaluation of a new approach to compute intervertebral disc height measurements from lateral radiographic views of the spine.
PURPOSE
Current standard methods to quantify disc height, namely distortion compensated Roentgen analysis (DCRA), have been mostly utilized in the lumbar and cervical spine and have strict exclusion criteria. Specifically, discs adjacent to a vertebral fracture are excluded from measurement, thus limiting the use of DCRA in studies that include older populations with a high prevalence of vertebral fractures. Thus, we developed and tested a modified DCRA algorithm that does not depend on vertebral shape.


METHODS
Participants included 1186 men and women from the Framingham Heart Study Offspring and Third Generation Multidetector CT Study. Lateral CT scout images were used to place 6 morphometry points around each vertebra at 13 vertebral levels in each participant. Disc heights were calculated utilizing these morphometry points using DCRA methodology and our modified version of DCRA, which requires information from fewer morphometry points than the standard DCRA.


RESULTS
Modified DCRA and standard DCRA measures of disc height are highly correlated, with concordance correlation coefficients above 0.999. Both measures demonstrate good inter- and intra-operator reproducibility. 13.9 % of available disc heights were not evaluable or excluded using the standard DCRA algorithm, while only 3.3 % of disc heights were not evaluable using our modified DCRA algorithm.


CONCLUSIONS
Using our modified DCRA algorithm, it is not necessary to exclude vertebrae with fracture or other deformity from disc height measurements as in the standard DCRA. Modified DCRA also yields identical measurements to the standard DCRA. Thus, the use of modified DCRA for quantitative assessment of disc height will lead to less missing data without any loss of accuracy, making it a preferred alternative to the current standard methodology.
['Allaire|Brett T|BT|', 'DePaolis Kaluza|M Clara|MC|', 'Bruno|Alexander G|AG|', 'Samelson|Elizabeth J|EJ|', 'Kiel|Douglas P|DP|', 'Anderson|Dennis E|DE|', 'Bouxsein|Mary L|ML|']
D000368:Aged D000465:Algorithms D003430:Cross-Sectional Studies D005260:Female D006801:Humans D007403:Intervertebral Disc D008297:Male D008875:Middle Aged D061330:Multidetector Computed Tomography D015203:Reproducibility of Results D012984:Software D013131:Spine
Intervertebral disc Disc height Radiograph Spine