[Differential diagnosis of the signal-compromised lunate in MRI].
OBJECTIVE
To define both the underlying pathology and diagnostic criteria in lunates presenting with conspicuous signal pattern in MRI.


METHODS
The retrospective evaluation of 2940 MRI examinations revealed 203 patients with signal alterations of the lunate. All MRI examinations were performed on 1.5-Tesla platforms using dedicated surface coils and an intravenous contrast agent. To establish a definitive diagnosis, a total of 252 MRI examinations (49 follow-ups), 22 CT examinations and 4 arthroscopic studies were obtained in addition to the obligatory conventional radiographs.


RESULTS
Incorporating all clinical data, radiographs and MRI examinations succeeded in assigning a diagnosis in 136 signal-compromised lunates (67.0 %), whereas additional diagnostic procedures or follow-up examinations were required for the definitive diagnosis in 57 cases (33.0 %). The most frequent entities were 51 cases of Kienbock's disease (25.1 %), 47 cases of ulnolunate-(triquetral) impaction syndromes (23.2 %) and 44 cases of intra-osseous ganglion cysts (21.7 %). Other pathologies included 23 degenerative, 19 traumatic and 10 inflammatory changes as well as 9 congenital conditions. For MRI assessment of the altered lunate, the most important parameters were location and morphology as well as involvement of the articular and osseous structures of the carpus.


CONCLUSIONS
The lunate may be affected by different pathological states of the wrist. In total, only one quarter of the signal-compromised lunate represented Kienboeck's disease.
Schmitt
R
R
Institut für Diagnostische und Interventionelle Radiologie, Herz- und Gefässklinik GmbH, Bad Neustadt an der Saale. schmitt.radiologie@herzchirurgie.de
Christopoulos
G
G
Kalb
K
K
Coblenz
G
G
Fröhner
S
S
Brunner
H
H
Krimmer
H
H
Lanz
U
U
D000293:Adolescent; D000328:Adult; D000368:Aged; D001182:Arthroscopy; D001847:Bone Diseases / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology; D001851:Bone Diseases, Metabolic / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000473:pathology; D003287:Contrast Media; D003937:Diagnosis, Differential; D005260:Female; D005500:Follow-Up Studies; D045888:Ganglion Cysts / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology; D006801:Humans; D012667:Lunate Bone / Q000000981:diagnostic imaging / Q000473:pathology*; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D010020:Osteonecrosis / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed
D003287:Contrast Media