Computerized digital imaging techniques provided by digital X-ray radiogrammetry as new diagnostic tool in rheumatoid arthritis.
OBJECTIVE
Our study evaluates digital x-ray radiogrammetry (DXR) and Radiogrammetry Kit (RK) as a new diagnostic method for the measurement of disease-related osteoporosis including quantification of joint space narrowing dependent on the severity of rheumatoid arthritis (RA).


METHODS
A total of 172 unselected patients with RA underwent computerized measurements of bone mineral density (BMD) and metacarpal index (MCI) by DXR, as well as a semiautomated measurement of joint space distances at the metacarpal-phalangeal articulation (JSD-MCP 2-5), both were analyzed from plain radiographs of the nondominant hand.


RESULTS
Correlations between DXR-BMD and DXR-MCI vs. parameters of RK were all significant (0.34 < R < 0.61; p < 0.01). An expected negative association was observed between RK parameters and the different scoring methods (-0.27 < R < -0.59). The maximum relative decrease in BMD vs. MCI as measured by DXR between the highest and lowest RA severity group was -27.7% vs. -27.5% (p < 0.01) for the modified Larsen Score, whereas the minimal value of relative DXR-BMD and DXR-MCI reduction could be documented for the Sharp Erosion Score (-20.8% vs. -26.8%; p < 0.01). The relative reduction of mean JSD-MCP using RK significantly varied from -25.0% (Sharp Erosion Score) to -41.2% (modified Larsen Score). In addition, an excellent reproducibility of DXR and RK could be verified.


CONCLUSIONS
DXR in combination with RK could be a promising, widely available diagnostic tool to supplement the different scoring methods of RA with quantitative data, allowing an earlier and improved diagnosis and more precision in determining disease progression.
Böttcher
Joachim
J
Institute of Diagnostic and Interventional Radiology, Friedrich-Schiller University Jena, Erlanger Allee 101, 07747, Jena, Germany. joachim.boettcher@med.uni-jena.de
Pfeil
Alexander
A
Rosholm
Anders
A
Schäfer
Max-Ludwig
ML
Malich
Ansgar
A
Petrovitch
Alexander
A
Seidl
Bettina
B
Lehmann
Gabriele
G
Mentzel
Hans-Joachim
HJ
Hein
Gert
G
Wolf
Gunter
G
Kaiser
Werner A
WA
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001172:Arthritis, Rheumatoid / Q000150:complications / Q000000981:diagnostic imaging* / Q000503:physiopathology; D015519:Bone Density; D018450:Disease Progression; D005260:Female; D050276:Hand Bones / Q000000981:diagnostic imaging / Q000503:physiopathology; D050823:Hand Joints / Q000000981:diagnostic imaging / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010024:Osteoporosis / Q000000981:diagnostic imaging / Q000209:etiology / Q000503:physiopathology; D011856:Radiographic Image Enhancement / Q000379:methods; D015203:Reproducibility of Results; D012720:Severity of Illness Index