Arthritis & Rheumatism, Volume 63,
November 2011 Abstract Supplement
Abstracts of the American College of
Rheumatology/Association of Rheumatology Health Professionals
Annual Scientific Meeting
Chicago, Illinois November 4-9, 2011.
Can Ultrasound (PDUS) Easily Detect Erosions? Evaluation of Physiological and Abnormal Cortical Breaks of Small Joints in Healthy Individuals (HI) and Rheumatoid Arthritis (RA) Patients by PDUS Comparison with Micro Computed Tomography (CT) Scan.
Finzel1, Stephanie, Aegerter2, Philippe, Schett1, Georg, D'Agostino2, Maria-Antonietta, OMERACT Ultrasound Task Force,
The correct detection of bone erosions in RA by ultrasound is sometimes delicate due to the presence of pitfalls such as physiological vessel channels, grooves, sesamoids and osteophytes. Thus, ultrasound needs further standardization. Objective: To evaluate by PDUS the size and location of physiological and abnormal cortical breaks in HI and RA patients by using mCT as gold standard.
Metacarpophalangeal joints (MCPJ) of both hands of 43 HI (without history of inflammatory joint disease) and 40 RA patients (disease duration > 6 months; fulfilling the new ACR/EULAR classification criteria) were examined by PDUS using a palmar, dorsal and, where possible, a lateral approach. All accessible joint facets were assessed in longitudinal and transversal planes. PDUS was performed by using an ESAOTE MyLab 70 (Genoa Italy) both in B- (linear array probe of 18 MHz) and PD-mode (10.2 MHz; PRF of 500). Cortical break was defined as a break in cortical lining detectable in two perpendicular planes. For each plane the width and the depth were recorded. Physiological and abnormal breaks were defined according to the opinion of ultrasonographer. Additionally, a mCT scan of MCPJ (2 to 5) was performed at a resolution of 82×82×82 mm voxel size of the clinically more affected hands of 26 RA patients and of the dominant hands of 17 HI. The prevalence, sensitivity and specificity of breaks as determined by PDUS and mCT were recorded and compared.
A total of 430 and 390 MCPJ were scanned by PDUS in HI and RA respectively. 48 and 81 MCPJ were additionally evaluated by mCT in HI and RA respectively. In HI, among the 1118 performed scans 226 breaks (20%) were recorded, 222 (98%) physiological (61% in the palmar side) and 4 (2%) pathological (3 in the lateral side). In RA patients 255 breaks were detected out of 1014 scans performed (25%). 143 (14%) were considered physiological (64% in the palmar side) and 112 (11%) as abnormal erosions (51% in the lateral side). All physiological breaks were considered as vessel channels, despite the absence of PD signal. Overall there was an excellent agreement between PDUS and mCT regarding the specificity of detection of physiological and abnormal breaks in HI and RA (Sp of 1 for HI and 0.95 for RA ) except for the dorsal side of MCP 2 (k values of 0 for HI and 0.1 for RA). Sensitivity was difficult to assess due to low sample size in both groups. Table 1 shows the mean (mm) cortical physiological and abnormal breaks by PDUS and mCT in HI and RA.
|PDUS (mean in mm)||mCT (mean in mm)|
|HI (physiological breaks)||1.85||2.2||1.77||2.18||0.66||1.41||0.61||1.51|
|RA (physiological breaks)||0.48||0.63||0.66||0.8||1.03||1.24||1.02||1.27|
|HI (abnomal breaks)||2.5||3.2||1.8||2.3||0.67||1.74||0.84||1.59|
|RA (abnormal breaks)||1.43||1.35||1.53||1.43||1.83||1.79||1.79||1.79|
Ultrasound is a valuable method for the detection of and the discrimination between abnormal (i.e. erosions) and physiological breaks in cortical bone. Predilection sides for nutritive vessels could be identified in both ultrasound and mCT. This study could work as a map for the correct detection of bone erosions in rheumatoid arthritis allowing for the discrimination between pathological and physiological breaks.
To cite this abstract, please use the following information:
Finzel, Stephanie, Aegerter, Philippe, Schett, Georg, D'Agostino, Maria-Antonietta, OMERACT Ultrasound Task Force, ; Can Ultrasound (PDUS) Easily Detect Erosions? Evaluation of Physiological and Abnormal Cortical Breaks of Small Joints in Healthy Individuals (HI) and Rheumatoid Arthritis (RA) Patients by PDUS Comparison with Micro Computed Tomography (CT) Scan. [abstract]. Arthritis Rheum 2011;63 Suppl 10 :807