Occult scaphoid fractures: comparison of multidetector CT and MR imaging--initial experience.
OBJECTIVE
To compare the diagnostic performance of multidetector computed tomography (CT) and magnetic resonance (MR) imaging in patients clinically suspected of having a scaphoid fracture and who had normal initial radiographs, with radiographs obtained 6 weeks after trauma as the reference standard.


METHODS
The ethics committee approved the study, and all patients gave written informed consent. Twenty-nine patients (17 male, 12 female; age range, 17-62 years; mean age, 34 years +/- 13) underwent multidetector CT and MR imaging within 6 days after trauma. CT data were obtained with 0.5-mm collimation. For image review, 0.7-mm-thick multiplanar reformations were performed in transverse, coronal, and sagittal planes relative to the wrist. The 1.0-T MR examination consisted of coronal and transverse short inversion time inversion-recovery, coronal and transverse T1-weighted spin-echo, and coronal volume-rendered T2-weighted gradient-echo sequences. Two radiologists analyzed the CT and MR images. A binomial test was used to evaluate the significance of the differences between MR imaging and CT in detection of scaphoid fractures and cortical involvement (P < .05).


RESULTS
The 6-week follow-up radiographs depicted a scaphoid fracture in 11 (38%) patients. Eight patients had a cortical fracture, while three patients had only a bandlike lucency within the trabecular portion of the scaphoid. MR imaging depicted all 11 fractures but only three [corrected] cortical fractures. Multidetector CT depicted all eight cortical fractures but failed to depict trabecular fractures. No false-positive fractures were seen on MR or CT images. Differences between MR imaging and CT were not significant for the detection of scaphoid fractures (P = .25) but were significant for cortical involvement (P = .03).


CONCLUSIONS
Multidetector CT is highly accurate in depicting occult cortical scaphoid fractures but appears inferior to MR imaging in depicting solely trabecular injury. MR imaging is inferior to multidetector CT in depicting cortical involvement.
Memarsadeghi
Mazda
M
Department of Radiology, Medical University of Vienna, General Hospital of Vienna, Waehringer Guertel 18-20, A-1090 Vienna, Austria. mazda.memarsadeghi@meduniwien.ac.at
Breitenseher
Martin J
MJ
Schaefer-Prokop
Cornelia
C
Weber
Michael
M
Aldrian
Silke
S
Gäbler
Christian
C
Prokop
Mathias
M
D000293:Adolescent; D000328:Adult; D002348:Carpal Bones / Q000000981:diagnostic imaging / Q000293:injuries / Q000473:pathology; D003951:Diagnostic Errors / Q000517:prevention & control*; D005260:Female; D005500:Follow-Up Studies; D005596:Fractures, Closed / Q000175:diagnosis* / Q000000981:diagnostic imaging; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D021361:Scaphoid Bone / Q000000981:diagnostic imaging / Q000293:injuries* / Q000473:pathology; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*