Using the dGEMRIC technique to evaluate cartilage health in the presence of surgical hardware at 3T : comparison of inversion recovery and saturation recovery approaches

UBC Faculty Research and Publications

Using the dGEMRIC technique to evaluate cartilage health in the presence of surgical hardware at 3T : comparison of inversion recovery and saturation recovery approaches d'Entremont, Agnes Germaine; Kolind, Shannon H.; Mädler, Burkhard; Wilson, David R.; MacKay, Alexander Lloyd

Abstract

Objective. To evaluate the effect of metal artifact reduction techniques on dGEMRIC T₁ calculation with surgical hardware present. Materials and Methods. We examined the effect of stainless steel and titanium hardware on dGEMRIC T₁ maps. We tested two strategies to reduce metal artifact in dGEMRIC: 1) saturation recovery (SR) instead of inversion recovery (IR) and 2) applying the Metal Artifact Reduction Sequence (MARS), in a gadolinium-doped agarose gel phantom and in vivo with titanium hardware. T₁ maps were obtained using custom curve-fitting software and phantom ROIs were defined to compare conditions (metal, MARS, IR, SR). Results. A large area of artifact appeared in phantom IR images with metal when TI≤700ms. IR maps with metal had additional artifact both in vivo and in the phantom (shifted null points, increased mean T₁ (+151% IR ROIartifact) and decreased mean inversion efficiency (f; 0.45 ROIartifact, versus 2 for perfect inversion)) compared to the SR maps (ROIartifact: +13% T1 SR, 0.95 versus 1 for perfect excitation), however SR produced noisier T₁ maps than IR (phantom SNR: 118 SR, 212 IR). MARS subtly reduced the extent of artifact in the phantom (IR and SR). Conclusion. dGEMRIC measurement in the presence of surgical hardware at 3T is possible with appropriately applied strategies. Measurements may work best in the presence of titanium and are severely limited with stainless steel. For regions near hardware where IR produces large artifacts making dGEMRIC analysis impossible, SRMARS may allow dGEMRIC measurements. The position and size of the IR artifact is variable, and must be assessed for each implant/imaging set-up.

Item Metadata

Title	Using the dGEMRIC technique to evaluate cartilage health in the presence of surgical hardware at 3T : comparison of inversion recovery and saturation recovery approaches
Alternate Title	dGEMRIC and metal artifact at 3T
Creator	d'Entremont, Agnes Germaine; Kolind, Shannon H.; Mädler, Burkhard; Wilson, David R.; MacKay, Alexander Lloyd
Contributor	University of British Columbia. Institute of Mental Health; Centre for Hip Health and Mobility
Date Issued	2014-03
Description	Objective. To evaluate the effect of metal artifact reduction techniques on dGEMRIC T₁ calculation with surgical hardware present. Materials and Methods. We examined the effect of stainless steel and titanium hardware on dGEMRIC T₁ maps. We tested two strategies to reduce metal artifact in dGEMRIC: 1) saturation recovery (SR) instead of inversion recovery (IR) and 2) applying the Metal Artifact Reduction Sequence (MARS), in a gadolinium-doped agarose gel phantom and in vivo with titanium hardware. T₁ maps were obtained using custom curve-fitting software and phantom ROIs were defined to compare conditions (metal, MARS, IR, SR). Results. A large area of artifact appeared in phantom IR images with metal when TI≤700ms. IR maps with metal had additional artifact both in vivo and in the phantom (shifted null points, increased mean T₁ (+151% IR ROIartifact) and decreased mean inversion efficiency (f; 0.45 ROIartifact, versus 2 for perfect inversion)) compared to the SR maps (ROIartifact: +13% T1 SR, 0.95 versus 1 for perfect excitation), however SR produced noisier T₁ maps than IR (phantom SNR: 118 SR, 212 IR). MARS subtly reduced the extent of artifact in the phantom (IR and SR). Conclusion. dGEMRIC measurement in the presence of surgical hardware at 3T is possible with appropriately applied strategies. Measurements may work best in the presence of titanium and are severely limited with stainless steel. For regions near hardware where IR produces large artifacts making dGEMRIC analysis impossible, SRMARS may allow dGEMRIC measurements. The position and size of the IR artifact is variable, and must be assessed for each implant/imaging set-up.
Subject	Metal artifact; dGEMRIC; Knee; Cartilage; Surgical implant; Magnetic resonance imaging
Genre	Article; Postprint
Type	Text
Language	eng
Date Available	2018-10-11
Provider	Vancouver : University of British Columbia Library
Rights	Attribution-NonCommercial-NoDerivatives 4.0 International
DOI	10.14288/1.0372527
URI	http://hdl.handle.net/2429/67478
Affiliation	Applied Science, Faculty of; Medicine, Faculty of; Science, Faculty of; Other UBC; Non UBC; Mechanical Engineering, Department of; Orthopaedic Surgery, Department of; Physics and Astronomy, Department of
Citation	Wilson DR, McWalter EJ, Johnston JD. The measurement of joint mechanics and their role in osteoarthritis genesis and progression. Rheumatic Disease Clinics of North America. 2013 Feb;39(1):21-44.
Publisher DOI	10.1016/j.rdc.2012.11.002
Peer Review Status	Reviewed
Scholarly Level	Faculty; Graduate
Rights URI	http://creativecommons.org/licenses/by-nc-nd/4.0/
Aggregated Source Repository	DSpace

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