TY - JOUR
T1 - Unicompartmental knee arthroplasty MRI
T2 - impact of slice-encoding for metal artefact correction MRI on image quality, findings and therapy decision
AU - Agten, Christoph A.
AU - Del Grande, Filippo
AU - Fucentese, Sandro F.
AU - Blatter, Samuel
AU - Pfirrmann, Christian W.A.
AU - Sutter, Reto
N1 - Publisher Copyright:
© 2015, European Society of Radiology.
PY - 2015/7/8
Y1 - 2015/7/8
N2 - Objectives: To evaluate the impact of slice-encoding for metal artefact correction (SEMAC) on image quality, findings, and therapy decision in patients with unicompartmental knee arthroplasty (UKA). Methods: Forty-five painful UKAs were examined at 1.5T-MRI (STIR, proton-density(PD)-weighted sequence, each with SEMAC and high-bandwidth). Artefact size, image quality, anatomic depiction, and clinically relevant findings were compared between SEMAC and high-bandwidth (2 readers). In 30 patients, therapy decision was retrospectively assessed by two orthopaedic surgeons without MRI, with high-bandwidth-MRI, and with SEMAC-MRI. Results: SEMAC reduced mean artefact size for STIR (11.8 cm2 vs. 37.7 cm2) and PD (16.8 cm2 vs. 18.9 cm2), p < 0.0005 for both comparisons. SEMAC showed more blurring than high-bandwidth, p < 0.0005. STIR-SEMAC revealed more bone marrow oedema (29 vs. 18 patients, p = 0.001, 30 vs. 13 patients, p < 0.0005, for reader 1 and 2 respectively). PD-SEMAC was worse in detecting meniscal lesions (6 missed, p = 0.031, 9 missed, p = 0.004, by reader 1 and 2 respectively) than PD-high-bandwidth. Revision-surgery was chosen in 12 and 11 patients without MRI (surgeon 1 and 2), with high-bandwidth-MRI in 15 and 14 patients, and with SEMAC-MRI in 19 and 14 patients. Conclusions: STIR-SEMAC was useful in detecting bone marrow oedema and influenced the orthopaedic surgeons’ decisions towards surgery, while PD-SEMAC showed no clinical benefit. Key Points: • Slice-encoding for metal artefact correction (SEMAC) MRI reduces metal-induced artefact size. • STIR SEMAC detects more bone marrow oedema in painful unicompartmental knee arthroplasty. • STIR SEMAC can help the orthopaedic surgeon with decision making. • PD SEMAC suffers from blurring of images, potentially masking relevant meniscal lesions. • PD SEMAC does not improve cartilage lesion detection in the non-operated compartments.
AB - Objectives: To evaluate the impact of slice-encoding for metal artefact correction (SEMAC) on image quality, findings, and therapy decision in patients with unicompartmental knee arthroplasty (UKA). Methods: Forty-five painful UKAs were examined at 1.5T-MRI (STIR, proton-density(PD)-weighted sequence, each with SEMAC and high-bandwidth). Artefact size, image quality, anatomic depiction, and clinically relevant findings were compared between SEMAC and high-bandwidth (2 readers). In 30 patients, therapy decision was retrospectively assessed by two orthopaedic surgeons without MRI, with high-bandwidth-MRI, and with SEMAC-MRI. Results: SEMAC reduced mean artefact size for STIR (11.8 cm2 vs. 37.7 cm2) and PD (16.8 cm2 vs. 18.9 cm2), p < 0.0005 for both comparisons. SEMAC showed more blurring than high-bandwidth, p < 0.0005. STIR-SEMAC revealed more bone marrow oedema (29 vs. 18 patients, p = 0.001, 30 vs. 13 patients, p < 0.0005, for reader 1 and 2 respectively). PD-SEMAC was worse in detecting meniscal lesions (6 missed, p = 0.031, 9 missed, p = 0.004, by reader 1 and 2 respectively) than PD-high-bandwidth. Revision-surgery was chosen in 12 and 11 patients without MRI (surgeon 1 and 2), with high-bandwidth-MRI in 15 and 14 patients, and with SEMAC-MRI in 19 and 14 patients. Conclusions: STIR-SEMAC was useful in detecting bone marrow oedema and influenced the orthopaedic surgeons’ decisions towards surgery, while PD-SEMAC showed no clinical benefit. Key Points: • Slice-encoding for metal artefact correction (SEMAC) MRI reduces metal-induced artefact size. • STIR SEMAC detects more bone marrow oedema in painful unicompartmental knee arthroplasty. • STIR SEMAC can help the orthopaedic surgeon with decision making. • PD SEMAC suffers from blurring of images, potentially masking relevant meniscal lesions. • PD SEMAC does not improve cartilage lesion detection in the non-operated compartments.
KW - Artefacts
KW - Decision making
KW - Knee replacement arthroplasty
KW - MRI
KW - SEMAC
UR - http://www.scopus.com/inward/record.url?scp=84930478235&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84930478235&partnerID=8YFLogxK
U2 - 10.1007/s00330-015-3596-4
DO - 10.1007/s00330-015-3596-4
M3 - Article
C2 - 25627351
AN - SCOPUS:84930478235
SN - 0938-7994
VL - 25
SP - 2184
EP - 2193
JO - European radiology
JF - European radiology
IS - 7
ER -