Interbody disc spacers for anterior spine fusion are made of different materials, such as titanium alloys or carbon fiber reinforced polymers (CFRP). Implant-related susceptibility artifacts can decrease the quality o...Interbody disc spacers for anterior spine fusion are made of different materials, such as titanium alloys or carbon fiber reinforced polymers (CFRP). Implant-related susceptibility artifacts can decrease the quality of MRI scans. This cadaveric study aimed to demonstrate the extent that implant-related MRI artifacting affects the post fusion differentiation of the spinal canal (SC) and intervertebral disc space (IDS). In 6 cadaveric porcine spines, we evaluated the post-im- plantation MRI scans of a titanium and CFRP spacer that differed in shape and surface qualities. A spacer made of human cortical bone was used as a control. A defined evaluation unit was divided into regions of interest (ROI) to characterize the SC and IDS. Considering 15 different MRI sequences read independently by an interobserver-validated team of specialists artifact-affected image quality of the median MRI slice was rated on a modified score of 0-1-2-3. A maximum score of 15 points for the SC and 9 points for the IDS (100%) was possible. Turbo spin echo sequences produced the best scores for both spacers and the control. Only the control achieved a score of 100%. For the IDS the titanium and CFRP spacer maximally scored 0% and 74%, for the SC 80% and 99%, respectively. By using favored T1 TSE sequences the CFRP-spacer represented clear advantages in post fusion spinal imaging. Independent of artifact dimensions the used scoring system allowed us to create an implant-related ranking of MRI scan quality in reference to the bone control.展开更多
Introduction: According to anterior spine fusion intervertebral disc spacers made of titanium or cobalt-chromium al-loys are of special interest. With regard to postoperative problems implant related artifacts can lea...Introduction: According to anterior spine fusion intervertebral disc spacers made of titanium or cobalt-chromium al-loys are of special interest. With regard to postoperative problems implant related artifacts can lead to a decreased MRI evaluation. The focus of this study was to compare the respective implant artifact artifact range dependend on different MRI sequences. To simplify artifact evaluation we introduced in this study a new developed 0-1-2 score. Material and Methods: We performed an MRI artifact evaluation of 2 different metallic intervertebral disc spacers (cobalt-chromium and titanium alloy). A carcass porcine spine was employed. Considering 12 defined spinal regions of interest we evaluated the respective implant artifact properties independent from the total artifact volume by using a new developed 0-1-2 score. The artifact range was documented for 15 different MRI-sequences. Results: For the titanium spacer as well as the cobalt-chromium-spacer an MRI evaluation of the implant/disc space situation could not be carried out. In contrast to the cobalt chromium spacer the titanium spacer allowed a good differentiation of the spinal canal opposite to the implant. Optimal MRI imaging results for both metallic intervertebral disc spacers could be achieved considering TSE sequences. Conclusion: A comparison of these two metallic spacers showed in all examined sequences clear advantages in favour of the titanium spacer. The best MRI representation of both tested implants by reducing implant related artifacts could be achieved with fast spin echo (TSE-) sequences. In spite of the use of TSE sequences a variability of susceptibility artifacts has to be included with regard to implant shape and material. With regard to the results of this study the easy use of a new developed artifact score represented a useful help to compare implant related MRI artifact properties independent from the actual implant related total artifact volume.展开更多
文摘Interbody disc spacers for anterior spine fusion are made of different materials, such as titanium alloys or carbon fiber reinforced polymers (CFRP). Implant-related susceptibility artifacts can decrease the quality of MRI scans. This cadaveric study aimed to demonstrate the extent that implant-related MRI artifacting affects the post fusion differentiation of the spinal canal (SC) and intervertebral disc space (IDS). In 6 cadaveric porcine spines, we evaluated the post-im- plantation MRI scans of a titanium and CFRP spacer that differed in shape and surface qualities. A spacer made of human cortical bone was used as a control. A defined evaluation unit was divided into regions of interest (ROI) to characterize the SC and IDS. Considering 15 different MRI sequences read independently by an interobserver-validated team of specialists artifact-affected image quality of the median MRI slice was rated on a modified score of 0-1-2-3. A maximum score of 15 points for the SC and 9 points for the IDS (100%) was possible. Turbo spin echo sequences produced the best scores for both spacers and the control. Only the control achieved a score of 100%. For the IDS the titanium and CFRP spacer maximally scored 0% and 74%, for the SC 80% and 99%, respectively. By using favored T1 TSE sequences the CFRP-spacer represented clear advantages in post fusion spinal imaging. Independent of artifact dimensions the used scoring system allowed us to create an implant-related ranking of MRI scan quality in reference to the bone control.
文摘Introduction: According to anterior spine fusion intervertebral disc spacers made of titanium or cobalt-chromium al-loys are of special interest. With regard to postoperative problems implant related artifacts can lead to a decreased MRI evaluation. The focus of this study was to compare the respective implant artifact artifact range dependend on different MRI sequences. To simplify artifact evaluation we introduced in this study a new developed 0-1-2 score. Material and Methods: We performed an MRI artifact evaluation of 2 different metallic intervertebral disc spacers (cobalt-chromium and titanium alloy). A carcass porcine spine was employed. Considering 12 defined spinal regions of interest we evaluated the respective implant artifact properties independent from the total artifact volume by using a new developed 0-1-2 score. The artifact range was documented for 15 different MRI-sequences. Results: For the titanium spacer as well as the cobalt-chromium-spacer an MRI evaluation of the implant/disc space situation could not be carried out. In contrast to the cobalt chromium spacer the titanium spacer allowed a good differentiation of the spinal canal opposite to the implant. Optimal MRI imaging results for both metallic intervertebral disc spacers could be achieved considering TSE sequences. Conclusion: A comparison of these two metallic spacers showed in all examined sequences clear advantages in favour of the titanium spacer. The best MRI representation of both tested implants by reducing implant related artifacts could be achieved with fast spin echo (TSE-) sequences. In spite of the use of TSE sequences a variability of susceptibility artifacts has to be included with regard to implant shape and material. With regard to the results of this study the easy use of a new developed artifact score represented a useful help to compare implant related MRI artifact properties independent from the actual implant related total artifact volume.
