DOI: 10.1148/rg.263055182
Multidetector CT for Visualization of Coronary Stents1
Francesca Pugliese, MD,
Filippo Cademartiri, MD, PhD,
Carlos van Mieghem, MD,
Willem B. Meijboom, MD,
Patrizia Malagutti, MD,
Nico R. A. Mollet, MD, PhD,
Carlo Martinoli, MD,
Pim J. de Feyter, MD, PhD and
Gabriel P. Krestin, MD, PhD
1 From the Departments of Radiology (F.P., F.C., N.R.A.M., G.P.K.) and Cardiology (C.v.M., W.B.M., P.M., P.J.d.F.), Erasmus MC, Dr Molenwaterplein 40, 3015 GD Rotterdam, the Netherlands; and Department of Radiology, University of Genoa, Genoa, Italy (C.M.). Presented as an education exhibit at the 2004 RSNA Annual Meeting. Received September 29, 2005; revision requested October 24 and received November 10; accepted December 15. All authors have no financial relationships to disclose.
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Figure 1a. Blooming effect on follow-up images obtained with 64-section CT in a patient who underwent stent implantation in the left circumflex coronary artery. (a) Longitudinal multiplanar reformatted image shows, at the outer edge of the stent, a calcified spot that contributes to beam hardening and hampers visualization of the in-stent lumen. Note the insufficient dilation of the stent proximal to the bulky calcification. (b, c) Sharp-kernel-filtered cross-sectional image (b), obtained at the level indicated in a (line), is less affected by blooming than is the smooth-kernel-filtered cross-sectional image (c).
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Figure 1b. Blooming effect on follow-up images obtained with 64-section CT in a patient who underwent stent implantation in the left circumflex coronary artery. (a) Longitudinal multiplanar reformatted image shows, at the outer edge of the stent, a calcified spot that contributes to beam hardening and hampers visualization of the in-stent lumen. Note the insufficient dilation of the stent proximal to the bulky calcification. (b, c) Sharp-kernel-filtered cross-sectional image (b), obtained at the level indicated in a (line), is less affected by blooming than is the smooth-kernel-filtered cross-sectional image (c).
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Figure 1c. Blooming effect on follow-up images obtained with 64-section CT in a patient who underwent stent implantation in the left circumflex coronary artery. (a) Longitudinal multiplanar reformatted image shows, at the outer edge of the stent, a calcified spot that contributes to beam hardening and hampers visualization of the in-stent lumen. Note the insufficient dilation of the stent proximal to the bulky calcification. (b, c) Sharp-kernel-filtered cross-sectional image (b), obtained at the level indicated in a (line), is less affected by blooming than is the smooth-kernel-filtered cross-sectional image (c).
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Figure 2a. Variation in the severity of metal-related artifacts at 64-section CT with variations in metallic content, design, and luminal diameter of the stent. (a) Curved multiplanar reformatted image obtained in a patient with a 4-mm-caliber stent in the proximal right coronary artery (arrow) and 2.50-mm-caliber (arrowhead) and 2.25-mm-caliber stents in the posterolateral artery. Although all three stents consist of the same material, the in-stent lumen in the two stents in the posterolateral artery is not visible because of the small stent caliber. Note the gap between the stents implanted in the posterolateral artery. (b) Image obtained in another patient, who underwent stent implantation (different stent type, 5-mm caliber) in the proximal circumflex artery, shows a more pronounced metal-related artifact than is visible in a.
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Figure 2b. Variation in the severity of metal-related artifacts at 64-section CT with variations in metallic content, design, and luminal diameter of the stent. (a) Curved multiplanar reformatted image obtained in a patient with a 4-mm-caliber stent in the proximal right coronary artery (arrow) and 2.50-mm-caliber (arrowhead) and 2.25-mm-caliber stents in the posterolateral artery. Although all three stents consist of the same material, the in-stent lumen in the two stents in the posterolateral artery is not visible because of the small stent caliber. Note the gap between the stents implanted in the posterolateral artery. (b) Image obtained in another patient, who underwent stent implantation (different stent type, 5-mm caliber) in the proximal circumflex artery, shows a more pronounced metal-related artifact than is visible in a.
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Figure 3a. Residual cardiac motion exacerbates metal-related artifacts at 64-section CT in a patient with a stent in the midportion of the right coronary artery and with a premature heartbeat recorded at ECG during scanning. (a, b) Images obtained from data acquired during gating with the original ECG tracing. On the volume-rendered image (a), a stepladder artifact (arrowheads) is visible at the level of the midportion of the right coronary artery. On the multiplanar reformatted image (b), a blurring of contours is visible. (c, d) Images obtained with cardiac gating after editing of the ECG tracing. To avoid a gap in the image data, the reconstruction window during the premature heartbeat was deleted and another was added to the subsequent cardiac cycle. This step eliminated the abrupt heart rate change related to the premature beat and allowed a more coherent reconstruction of the data set. On the volume-rendered image (c), the appearance of the stent (arrow) is unaffected by motion artifacts. Likewise, the in-stent lumen is well depicted on the multiplanar reformatted image (d).
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Figure 3b. Residual cardiac motion exacerbates metal-related artifacts at 64-section CT in a patient with a stent in the midportion of the right coronary artery and with a premature heartbeat recorded at ECG during scanning. (a, b) Images obtained from data acquired during gating with the original ECG tracing. On the volume-rendered image (a), a stepladder artifact (arrowheads) is visible at the level of the midportion of the right coronary artery. On the multiplanar reformatted image (b), a blurring of contours is visible. (c, d) Images obtained with cardiac gating after editing of the ECG tracing. To avoid a gap in the image data, the reconstruction window during the premature heartbeat was deleted and another was added to the subsequent cardiac cycle. This step eliminated the abrupt heart rate change related to the premature beat and allowed a more coherent reconstruction of the data set. On the volume-rendered image (c), the appearance of the stent (arrow) is unaffected by motion artifacts. Likewise, the in-stent lumen is well depicted on the multiplanar reformatted image (d).
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Figure 3c. Residual cardiac motion exacerbates metal-related artifacts at 64-section CT in a patient with a stent in the midportion of the right coronary artery and with a premature heartbeat recorded at ECG during scanning. (a, b) Images obtained from data acquired during gating with the original ECG tracing. On the volume-rendered image (a), a stepladder artifact (arrowheads) is visible at the level of the midportion of the right coronary artery. On the multiplanar reformatted image (b), a blurring of contours is visible. (c, d) Images obtained with cardiac gating after editing of the ECG tracing. To avoid a gap in the image data, the reconstruction window during the premature heartbeat was deleted and another was added to the subsequent cardiac cycle. This step eliminated the abrupt heart rate change related to the premature beat and allowed a more coherent reconstruction of the data set. On the volume-rendered image (c), the appearance of the stent (arrow) is unaffected by motion artifacts. Likewise, the in-stent lumen is well depicted on the multiplanar reformatted image (d).
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Figure 3d. Residual cardiac motion exacerbates metal-related artifacts at 64-section CT in a patient with a stent in the midportion of the right coronary artery and with a premature heartbeat recorded at ECG during scanning. (a, b) Images obtained from data acquired during gating with the original ECG tracing. On the volume-rendered image (a), a stepladder artifact (arrowheads) is visible at the level of the midportion of the right coronary artery. On the multiplanar reformatted image (b), a blurring of contours is visible. (c, d) Images obtained with cardiac gating after editing of the ECG tracing. To avoid a gap in the image data, the reconstruction window during the premature heartbeat was deleted and another was added to the subsequent cardiac cycle. This step eliminated the abrupt heart rate change related to the premature beat and allowed a more coherent reconstruction of the data set. On the volume-rendered image (c), the appearance of the stent (arrow) is unaffected by motion artifacts. Likewise, the in-stent lumen is well depicted on the multiplanar reformatted image (d).
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Figure 4a. Visibility of low-contrast structures with different convolution filters. The most appropriate filter must be chosen so that an advantageous balance is achieved between the visibility of low-contrast structures and the quantity of image noise. (a) Conventional coronary angiogram shows nonsignificant neointimal hyperplasia in the distal portion of the right coronary artery (arrowheads). (b–f) Multidetector 64-section CT angiograms obtained in a patient with multiple stents in the right coronary artery. On the image reconstructed with a smooth convolution filter (B20f) (b), the luminal defect (*) is hardly visible. On the image reconstructed with a medium-smooth convolution filter (B30f) (c), the defect (*) is visible but quite blurred. The image reconstructed with a dedicated edge-enhancing kernel (B46f) (d) allows visualization of in-stent neointimal hyperplasia (*), with good contrast between the defect and the surrounding structures (stent scaffold, enhanced lumen). On the images reconstructed with sharp (B60f) (e) and very sharp (B70f) (f) convolution filters, the edge enhancement does not provide clearer depiction of the defect (*) but, instead, greater amounts of image noise.
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Figure 4b. Visibility of low-contrast structures with different convolution filters. The most appropriate filter must be chosen so that an advantageous balance is achieved between the visibility of low-contrast structures and the quantity of image noise. (a) Conventional coronary angiogram shows nonsignificant neointimal hyperplasia in the distal portion of the right coronary artery (arrowheads). (b–f) Multidetector 64-section CT angiograms obtained in a patient with multiple stents in the right coronary artery. On the image reconstructed with a smooth convolution filter (B20f) (b), the luminal defect (*) is hardly visible. On the image reconstructed with a medium-smooth convolution filter (B30f) (c), the defect (*) is visible but quite blurred. The image reconstructed with a dedicated edge-enhancing kernel (B46f) (d) allows visualization of in-stent neointimal hyperplasia (*), with good contrast between the defect and the surrounding structures (stent scaffold, enhanced lumen). On the images reconstructed with sharp (B60f) (e) and very sharp (B70f) (f) convolution filters, the edge enhancement does not provide clearer depiction of the defect (*) but, instead, greater amounts of image noise.
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Figure 4c. Visibility of low-contrast structures with different convolution filters. The most appropriate filter must be chosen so that an advantageous balance is achieved between the visibility of low-contrast structures and the quantity of image noise. (a) Conventional coronary angiogram shows nonsignificant neointimal hyperplasia in the distal portion of the right coronary artery (arrowheads). (b–f) Multidetector 64-section CT angiograms obtained in a patient with multiple stents in the right coronary artery. On the image reconstructed with a smooth convolution filter (B20f) (b), the luminal defect (*) is hardly visible. On the image reconstructed with a medium-smooth convolution filter (B30f) (c), the defect (*) is visible but quite blurred. The image reconstructed with a dedicated edge-enhancing kernel (B46f) (d) allows visualization of in-stent neointimal hyperplasia (*), with good contrast between the defect and the surrounding structures (stent scaffold, enhanced lumen). On the images reconstructed with sharp (B60f) (e) and very sharp (B70f) (f) convolution filters, the edge enhancement does not provide clearer depiction of the defect (*) but, instead, greater amounts of image noise.
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Figure 4d. Visibility of low-contrast structures with different convolution filters. The most appropriate filter must be chosen so that an advantageous balance is achieved between the visibility of low-contrast structures and the quantity of image noise. (a) Conventional coronary angiogram shows nonsignificant neointimal hyperplasia in the distal portion of the right coronary artery (arrowheads). (b–f) Multidetector 64-section CT angiograms obtained in a patient with multiple stents in the right coronary artery. On the image reconstructed with a smooth convolution filter (B20f) (b), the luminal defect (*) is hardly visible. On the image reconstructed with a medium-smooth convolution filter (B30f) (c), the defect (*) is visible but quite blurred. The image reconstructed with a dedicated edge-enhancing kernel (B46f) (d) allows visualization of in-stent neointimal hyperplasia (*), with good contrast between the defect and the surrounding structures (stent scaffold, enhanced lumen). On the images reconstructed with sharp (B60f) (e) and very sharp (B70f) (f) convolution filters, the edge enhancement does not provide clearer depiction of the defect (*) but, instead, greater amounts of image noise.
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Figure 4e. Visibility of low-contrast structures with different convolution filters. The most appropriate filter must be chosen so that an advantageous balance is achieved between the visibility of low-contrast structures and the quantity of image noise. (a) Conventional coronary angiogram shows nonsignificant neointimal hyperplasia in the distal portion of the right coronary artery (arrowheads). (b–f) Multidetector 64-section CT angiograms obtained in a patient with multiple stents in the right coronary artery. On the image reconstructed with a smooth convolution filter (B20f) (b), the luminal defect (*) is hardly visible. On the image reconstructed with a medium-smooth convolution filter (B30f) (c), the defect (*) is visible but quite blurred. The image reconstructed with a dedicated edge-enhancing kernel (B46f) (d) allows visualization of in-stent neointimal hyperplasia (*), with good contrast between the defect and the surrounding structures (stent scaffold, enhanced lumen). On the images reconstructed with sharp (B60f) (e) and very sharp (B70f) (f) convolution filters, the edge enhancement does not provide clearer depiction of the defect (*) but, instead, greater amounts of image noise.
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Figure 4f. Visibility of low-contrast structures with different convolution filters. The most appropriate filter must be chosen so that an advantageous balance is achieved between the visibility of low-contrast structures and the quantity of image noise. (a) Conventional coronary angiogram shows nonsignificant neointimal hyperplasia in the distal portion of the right coronary artery (arrowheads). (b–f) Multidetector 64-section CT angiograms obtained in a patient with multiple stents in the right coronary artery. On the image reconstructed with a smooth convolution filter (B20f) (b), the luminal defect (*) is hardly visible. On the image reconstructed with a medium-smooth convolution filter (B30f) (c), the defect (*) is visible but quite blurred. The image reconstructed with a dedicated edge-enhancing kernel (B46f) (d) allows visualization of in-stent neointimal hyperplasia (*), with good contrast between the defect and the surrounding structures (stent scaffold, enhanced lumen). On the images reconstructed with sharp (B60f) (e) and very sharp (B70f) (f) convolution filters, the edge enhancement does not provide clearer depiction of the defect (*) but, instead, greater amounts of image noise.
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Figure 5a. Combined effects of the selected filter and window settings on image contrast and noise at 64-section CT coronary angiography. (a–c) Images obtained with a medium-smooth convolution kernel (B30f). (d–f) Images obtained with a dedicated sharp convolution kernel (B46f). Note that d–f more clearly depict the in-stent lumen than do a–c. The standard soft-tissue window width (W) (a, d) is too narrow and accentuates blooming artifacts. On the image filtered with a medium-smooth convolution kernel (a), the blooming effect totally obscures the in-stent lumen. With exaggerated widening of the window (b, e), the blooming effect is decreased, but this occurs at the expense of overall image contrast. Setting the window center (C) at approximately 300 HU and choosing a width (W) of approximately 1500 HU allows a more favorable balance between image contrast and noise (c, f). However, the window settings alone are not sufficient to ensure optimal depiction of the inner lumen (c). The combined use of a dedicated edge-enhancing convolution kernel, which increases image spatial resolution, and appropriate window settings to compensate for filter-related noise allows the most favorable in-stent lumen visualization (f).
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Figure 5b. Combined effects of the selected filter and window settings on image contrast and noise at 64-section CT coronary angiography. (a–c) Images obtained with a medium-smooth convolution kernel (B30f). (d–f) Images obtained with a dedicated sharp convolution kernel (B46f). Note that d–f more clearly depict the in-stent lumen than do a–c. The standard soft-tissue window width (W) (a, d) is too narrow and accentuates blooming artifacts. On the image filtered with a medium-smooth convolution kernel (a), the blooming effect totally obscures the in-stent lumen. With exaggerated widening of the window (b, e), the blooming effect is decreased, but this occurs at the expense of overall image contrast. Setting the window center (C) at approximately 300 HU and choosing a width (W) of approximately 1500 HU allows a more favorable balance between image contrast and noise (c, f). However, the window settings alone are not sufficient to ensure optimal depiction of the inner lumen (c). The combined use of a dedicated edge-enhancing convolution kernel, which increases image spatial resolution, and appropriate window settings to compensate for filter-related noise allows the most favorable in-stent lumen visualization (f).
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Figure 5c. Combined effects of the selected filter and window settings on image contrast and noise at 64-section CT coronary angiography. (a–c) Images obtained with a medium-smooth convolution kernel (B30f). (d–f) Images obtained with a dedicated sharp convolution kernel (B46f). Note that d–f more clearly depict the in-stent lumen than do a–c. The standard soft-tissue window width (W) (a, d) is too narrow and accentuates blooming artifacts. On the image filtered with a medium-smooth convolution kernel (a), the blooming effect totally obscures the in-stent lumen. With exaggerated widening of the window (b, e), the blooming effect is decreased, but this occurs at the expense of overall image contrast. Setting the window center (C) at approximately 300 HU and choosing a width (W) of approximately 1500 HU allows a more favorable balance between image contrast and noise (c, f). However, the window settings alone are not sufficient to ensure optimal depiction of the inner lumen (c). The combined use of a dedicated edge-enhancing convolution kernel, which increases image spatial resolution, and appropriate window settings to compensate for filter-related noise allows the most favorable in-stent lumen visualization (f).
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Figure 5d. Combined effects of the selected filter and window settings on image contrast and noise at 64-section CT coronary angiography. (a–c) Images obtained with a medium-smooth convolution kernel (B30f). (d–f) Images obtained with a dedicated sharp convolution kernel (B46f). Note that d–f more clearly depict the in-stent lumen than do a–c. The standard soft-tissue window width (W) (a, d) is too narrow and accentuates blooming artifacts. On the image filtered with a medium-smooth convolution kernel (a), the blooming effect totally obscures the in-stent lumen. With exaggerated widening of the window (b, e), the blooming effect is decreased, but this occurs at the expense of overall image contrast. Setting the window center (C) at approximately 300 HU and choosing a width (W) of approximately 1500 HU allows a more favorable balance between image contrast and noise (c, f). However, the window settings alone are not sufficient to ensure optimal depiction of the inner lumen (c). The combined use of a dedicated edge-enhancing convolution kernel, which increases image spatial resolution, and appropriate window settings to compensate for filter-related noise allows the most favorable in-stent lumen visualization (f).
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Figure 5e. Combined effects of the selected filter and window settings on image contrast and noise at 64-section CT coronary angiography. (a–c) Images obtained with a medium-smooth convolution kernel (B30f). (d–f) Images obtained with a dedicated sharp convolution kernel (B46f). Note that d–f more clearly depict the in-stent lumen than do a–c. The standard soft-tissue window width (W) (a, d) is too narrow and accentuates blooming artifacts. On the image filtered with a medium-smooth convolution kernel (a), the blooming effect totally obscures the in-stent lumen. With exaggerated widening of the window (b, e), the blooming effect is decreased, but this occurs at the expense of overall image contrast. Setting the window center (C) at approximately 300 HU and choosing a width (W) of approximately 1500 HU allows a more favorable balance between image contrast and noise (c, f). However, the window settings alone are not sufficient to ensure optimal depiction of the inner lumen (c). The combined use of a dedicated edge-enhancing convolution kernel, which increases image spatial resolution, and appropriate window settings to compensate for filter-related noise allows the most favorable in-stent lumen visualization (f).
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Figure 5f. Combined effects of the selected filter and window settings on image contrast and noise at 64-section CT coronary angiography. (a–c) Images obtained with a medium-smooth convolution kernel (B30f). (d–f) Images obtained with a dedicated sharp convolution kernel (B46f). Note that d–f more clearly depict the in-stent lumen than do a–c. The standard soft-tissue window width (W) (a, d) is too narrow and accentuates blooming artifacts. On the image filtered with a medium-smooth convolution kernel (a), the blooming effect totally obscures the in-stent lumen. With exaggerated widening of the window (b, e), the blooming effect is decreased, but this occurs at the expense of overall image contrast. Setting the window center (C) at approximately 300 HU and choosing a width (W) of approximately 1500 HU allows a more favorable balance between image contrast and noise (c, f). However, the window settings alone are not sufficient to ensure optimal depiction of the inner lumen (c). The combined use of a dedicated edge-enhancing convolution kernel, which increases image spatial resolution, and appropriate window settings to compensate for filter-related noise allows the most favorable in-stent lumen visualization (f).
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Figure 6a. Selection of suitable threshold ranges and opacity settings allows simulation of an endoscopic view of the inner vessel surface and makes it possible to recognize different designs of the metal scaffold in stents. A slotted tubular stent (a) and a corrugated ring stent (b) are currently used for the treatment of most coronary lesions. Both stents have a diameter of 3 mm. The amount of image noise may prevent successful application of this technique for depiction of the lumen in stents with very small diameters.
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Figure 6b. Selection of suitable threshold ranges and opacity settings allows simulation of an endoscopic view of the inner vessel surface and makes it possible to recognize different designs of the metal scaffold in stents. A slotted tubular stent (a) and a corrugated ring stent (b) are currently used for the treatment of most coronary lesions. Both stents have a diameter of 3 mm. The amount of image noise may prevent successful application of this technique for depiction of the lumen in stents with very small diameters.
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Figure 7a. In-stent occlusion in a patient with recurrent angina pectoris 18 months after implantation of two stents in the right coronary artery. CT was performed after conventional angiography failed to depict the right coronary artery. (a) Multiplanar reformatted image shows lower attenuation inside the stent lumina than in the proximal untreated tract of the right coronary artery, a gap between the occluded stents, and collateral filling (*). (b–d) Cross-sectional images obtained at the proximal end of the stent (b) (1 in a), in the middle portion (c) (2 in a), and at the distal end (d) (3 in a) show the appearances of patency, occlusion, and patency, respectively. (e, f) Conventional angiograms provide information about the presence of collateral filling (* in e) and the length of the occlusion. This information enabled planning for percutaneous revascularization, which was successful, as evident from a comparison of the pretreatment image (e) and the posttreatment image (f).
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Figure 7b. In-stent occlusion in a patient with recurrent angina pectoris 18 months after implantation of two stents in the right coronary artery. CT was performed after conventional angiography failed to depict the right coronary artery. (a) Multiplanar reformatted image shows lower attenuation inside the stent lumina than in the proximal untreated tract of the right coronary artery, a gap between the occluded stents, and collateral filling (*). (b–d) Cross-sectional images obtained at the proximal end of the stent (b) (1 in a), in the middle portion (c) (2 in a), and at the distal end (d) (3 in a) show the appearances of patency, occlusion, and patency, respectively. (e, f) Conventional angiograms provide information about the presence of collateral filling (* in e) and the length of the occlusion. This information enabled planning for percutaneous revascularization, which was successful, as evident from a comparison of the pretreatment image (e) and the posttreatment image (f).
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Figure 7c. In-stent occlusion in a patient with recurrent angina pectoris 18 months after implantation of two stents in the right coronary artery. CT was performed after conventional angiography failed to depict the right coronary artery. (a) Multiplanar reformatted image shows lower attenuation inside the stent lumina than in the proximal untreated tract of the right coronary artery, a gap between the occluded stents, and collateral filling (*). (b–d) Cross-sectional images obtained at the proximal end of the stent (b) (1 in a), in the middle portion (c) (2 in a), and at the distal end (d) (3 in a) show the appearances of patency, occlusion, and patency, respectively. (e, f) Conventional angiograms provide information about the presence of collateral filling (* in e) and the length of the occlusion. This information enabled planning for percutaneous revascularization, which was successful, as evident from a comparison of the pretreatment image (e) and the posttreatment image (f).
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Figure 7d. In-stent occlusion in a patient with recurrent angina pectoris 18 months after implantation of two stents in the right coronary artery. CT was performed after conventional angiography failed to depict the right coronary artery. (a) Multiplanar reformatted image shows lower attenuation inside the stent lumina than in the proximal untreated tract of the right coronary artery, a gap between the occluded stents, and collateral filling (*). (b–d) Cross-sectional images obtained at the proximal end of the stent (b) (1 in a), in the middle portion (c) (2 in a), and at the distal end (d) (3 in a) show the appearances of patency, occlusion, and patency, respectively. (e, f) Conventional angiograms provide information about the presence of collateral filling (* in e) and the length of the occlusion. This information enabled planning for percutaneous revascularization, which was successful, as evident from a comparison of the pretreatment image (e) and the posttreatment image (f).
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Figure 7e. In-stent occlusion in a patient with recurrent angina pectoris 18 months after implantation of two stents in the right coronary artery. CT was performed after conventional angiography failed to depict the right coronary artery. (a) Multiplanar reformatted image shows lower attenuation inside the stent lumina than in the proximal untreated tract of the right coronary artery, a gap between the occluded stents, and collateral filling (*). (b–d) Cross-sectional images obtained at the proximal end of the stent (b) (1 in a), in the middle portion (c) (2 in a), and at the distal end (d) (3 in a) show the appearances of patency, occlusion, and patency, respectively. (e, f) Conventional angiograms provide information about the presence of collateral filling (* in e) and the length of the occlusion. This information enabled planning for percutaneous revascularization, which was successful, as evident from a comparison of the pretreatment image (e) and the posttreatment image (f).
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Figure 7f. In-stent occlusion in a patient with recurrent angina pectoris 18 months after implantation of two stents in the right coronary artery. CT was performed after conventional angiography failed to depict the right coronary artery. (a) Multiplanar reformatted image shows lower attenuation inside the stent lumina than in the proximal untreated tract of the right coronary artery, a gap between the occluded stents, and collateral filling (*). (b–d) Cross-sectional images obtained at the proximal end of the stent (b) (1 in a), in the middle portion (c) (2 in a), and at the distal end (d) (3 in a) show the appearances of patency, occlusion, and patency, respectively. (e, f) Conventional angiograms provide information about the presence of collateral filling (* in e) and the length of the occlusion. This information enabled planning for percutaneous revascularization, which was successful, as evident from a comparison of the pretreatment image (e) and the posttreatment image (f).
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Figure 8a. T stent implantation at the left main coronary artery bifurcation. (a) Volume-rendered image obtained with 64-section CT shows the left main coronary artery and circumflex artery (arrow), which constitute the main branch, and the anterior descending artery (arrowhead), the side branch for stent implantation. (b–e) T-stent cross-sectional diagram (b), curved multiplanar reformatted image (c), and cross-sectional images (d, e) obtained in the planes indicated in c show overlap of the metal struts only at the bifurcation point.
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Figure 8b. T stent implantation at the left main coronary artery bifurcation. (a) Volume-rendered image obtained with 64-section CT shows the left main coronary artery and circumflex artery (arrow), which constitute the main branch, and the anterior descending artery (arrowhead), the side branch for stent implantation. (b–e) T-stent cross-sectional diagram (b), curved multiplanar reformatted image (c), and cross-sectional images (d, e) obtained in the planes indicated in c show overlap of the metal struts only at the bifurcation point.
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Figure 8c. T stent implantation at the left main coronary artery bifurcation. (a) Volume-rendered image obtained with 64-section CT shows the left main coronary artery and circumflex artery (arrow), which constitute the main branch, and the anterior descending artery (arrowhead), the side branch for stent implantation. (b–e) T-stent cross-sectional diagram (b), curved multiplanar reformatted image (c), and cross-sectional images (d, e) obtained in the planes indicated in c show overlap of the metal struts only at the bifurcation point.
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Figure 8d. T stent implantation at the left main coronary artery bifurcation. (a) Volume-rendered image obtained with 64-section CT shows the left main coronary artery and circumflex artery (arrow), which constitute the main branch, and the anterior descending artery (arrowhead), the side branch for stent implantation. (b–e) T-stent cross-sectional diagram (b), curved multiplanar reformatted image (c), and cross-sectional images (d, e) obtained in the planes indicated in c show overlap of the metal struts only at the bifurcation point.
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Figure 8e. T stent implantation at the left main coronary artery bifurcation. (a) Volume-rendered image obtained with 64-section CT shows the left main coronary artery and circumflex artery (arrow), which constitute the main branch, and the anterior descending artery (arrowhead), the side branch for stent implantation. (b–e) T-stent cross-sectional diagram (b), curved multiplanar reformatted image (c), and cross-sectional images (d, e) obtained in the planes indicated in c show overlap of the metal struts only at the bifurcation point.
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Figure 9a. V stent implantation in the left coronary artery. (a, b) Volume-rendered image (a) and multiplanar reformatted image (b) show the left main artery and the anterior descending, intermediate, and circumflex branches, in which stents were placed to provide full coverage of the branching point. (c) Diagram of the V stent technique shows overlap of the metal struts only at the trifurcation. (d, e) Cross-sectional images, obtained in the planes shown in b, show the slim and symmetric profiles of the stents, both proximally (d) and at the level of the carina (e). (f) Volume-rendered image obtained for visualization of the vessel lumen provides a simulated endoscopic view of the origin of the three branches (1–3).
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Figure 9b. V stent implantation in the left coronary artery. (a, b) Volume-rendered image (a) and multiplanar reformatted image (b) show the left main artery and the anterior descending, intermediate, and circumflex branches, in which stents were placed to provide full coverage of the branching point. (c) Diagram of the V stent technique shows overlap of the metal struts only at the trifurcation. (d, e) Cross-sectional images, obtained in the planes shown in b, show the slim and symmetric profiles of the stents, both proximally (d) and at the level of the carina (e). (f) Volume-rendered image obtained for visualization of the vessel lumen provides a simulated endoscopic view of the origin of the three branches (1–3).
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Figure 9c. V stent implantation in the left coronary artery. (a, b) Volume-rendered image (a) and multiplanar reformatted image (b) show the left main artery and the anterior descending, intermediate, and circumflex branches, in which stents were placed to provide full coverage of the branching point. (c) Diagram of the V stent technique shows overlap of the metal struts only at the trifurcation. (d, e) Cross-sectional images, obtained in the planes shown in b, show the slim and symmetric profiles of the stents, both proximally (d) and at the level of the carina (e). (f) Volume-rendered image obtained for visualization of the vessel lumen provides a simulated endoscopic view of the origin of the three branches (1–3).
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Figure 9d. V stent implantation in the left coronary artery. (a, b) Volume-rendered image (a) and multiplanar reformatted image (b) show the left main artery and the anterior descending, intermediate, and circumflex branches, in which stents were placed to provide full coverage of the branching point. (c) Diagram of the V stent technique shows overlap of the metal struts only at the trifurcation. (d, e) Cross-sectional images, obtained in the planes shown in b, show the slim and symmetric profiles of the stents, both proximally (d) and at the level of the carina (e). (f) Volume-rendered image obtained for visualization of the vessel lumen provides a simulated endoscopic view of the origin of the three branches (1–3).
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Figure 9e. V stent implantation in the left coronary artery. (a, b) Volume-rendered image (a) and multiplanar reformatted image (b) show the left main artery and the anterior descending, intermediate, and circumflex branches, in which stents were placed to provide full coverage of the branching point. (c) Diagram of the V stent technique shows overlap of the metal struts only at the trifurcation. (d, e) Cross-sectional images, obtained in the planes shown in b, show the slim and symmetric profiles of the stents, both proximally (d) and at the level of the carina (e). (f) Volume-rendered image obtained for visualization of the vessel lumen provides a simulated endoscopic view of the origin of the three branches (1–3).
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Figure 9f. V stent implantation in the left coronary artery. (a, b) Volume-rendered image (a) and multiplanar reformatted image (b) show the left main artery and the anterior descending, intermediate, and circumflex branches, in which stents were placed to provide full coverage of the branching point. (c) Diagram of the V stent technique shows overlap of the metal struts only at the trifurcation. (d, e) Cross-sectional images, obtained in the planes shown in b, show the slim and symmetric profiles of the stents, both proximally (d) and at the level of the carina (e). (f) Volume-rendered image obtained for visualization of the vessel lumen provides a simulated endoscopic view of the origin of the three branches (1–3).
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Figure 10a. Y stent implantation at the bifurcation of the left main coronary artery. (a) Volume-rendered image shows the point of bifurcation, at which two stents were implanted in a configuration resembling a pair of trousers or culottes. Cx = left circumflex artery, LAD = left anterior descending artery. (b) Multiplanar reformatted image shows stent patency at the level of the bifurcation. (c) Diagram shows the concentrically deployed stents, which overlap near the point of bifurcation. (d, e) Cross-sectional images, obtained in the planes shown in b, depict a thicker stent profile in the parent vessel (d) at a level near the side-branch ostium (e).
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Figure 10b. Y stent implantation at the bifurcation of the left main coronary artery. (a) Volume-rendered image shows the point of bifurcation, at which two stents were implanted in a configuration resembling a pair of trousers or culottes. Cx = left circumflex artery, LAD = left anterior descending artery. (b) Multiplanar reformatted image shows stent patency at the level of the bifurcation. (c) Diagram shows the concentrically deployed stents, which overlap near the point of bifurcation. (d, e) Cross-sectional images, obtained in the planes shown in b, depict a thicker stent profile in the parent vessel (d)
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Figure 10c. Y stent implantation at the bifurcation of the left main coronary artery. (a) Volume-rendered image shows the point of bifurcation, at which two stents were implanted in a configuration resembling a pair of trousers or culottes. Cx = left circumflex artery, LAD = left anterior descending artery. (b) Multiplanar reformatted image shows stent patency at the level of the bifurcation. (c) Diagram shows the concentrically deployed stents, which overlap near the point of bifurcation. (d, e) Cross-sectional images, obtained in the planes shown in b, depict a thicker stent profile in the parent vessel (d) at a level near the side-branch ostium (e).
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Figure 10d. Y stent implantation at the bifurcation of the left main coronary artery. (a) Volume-rendered image shows the point of bifurcation, at which two stents were implanted in a configuration resembling a pair of trousers or culottes. Cx = left circumflex artery, LAD = left anterior descending artery. (b) Multiplanar reformatted image shows stent patency at the level of the bifurcation. (c) Diagram shows the concentrically deployed stents, which overlap near the point of bifurcation. (d, e) Cross-sectional images, obtained in the planes shown in b, depict a thicker stent profile in the parent vessel (d) at a level near the side-branch ostium (e).
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Figure 10e. Y stent implantation at the bifurcation of the left main coronary artery. (a) Volume-rendered image shows the point of bifurcation, at which two stents were implanted in a configuration resembling a pair of trousers or culottes. Cx = left circumflex artery, LAD = left anterior descending artery. (b) Multiplanar reformatted image shows stent patency at the level of the bifurcation. (c) Diagram shows the concentrically deployed stents, which overlap near the point of bifurcation. (d, e) Cross-sectional images, obtained in the planes shown in b, depict a thicker stent profile in the parent vessel (d)
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Figure 11a. Crush stent placement at the circumflex-marginal artery bifurcation. (a, b) Volume-rendered image (a) and curved multiplanar reformatted image (b) allow assessment of the stent configuration. (c) Diagram shows the multiple layers of metal that produce an asymmetric appearance of the cross-sectional stent profile. (d, e) Cross-sectional images, obtained in the planes shown in b, show asymmetric high attenuation where the layers of metal overlap, both proximal to the bifurcation (d) and across the ostium of the side-branch vessel (e).
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Figure 11b. Crush stent placement at the circumflex-marginal artery bifurcation. (a, b) Volume-rendered image (a) and curved multiplanar reformatted image (b) allow assessment of the stent configuration. (c) Diagram shows the multiple layers of metal that produce an asymmetric appearance of the cross-sectional stent profile. (d, e) Cross-sectional images, obtained in the planes shown in b, show asymmetric high attenuation where the layers of metal overlap, both proximal to the bifurcation (d) and across the ostium of the side-branch vessel (e).
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Figure 11c. Crush stent placement at the circumflex-marginal artery bifurcation. (a, b) Volume-rendered image (a) and curved multiplanar reformatted image (b) allow assessment of the stent configuration. (c) Diagram shows the multiple layers of metal that produce an asymmetric appearance of the cross-sectional stent profile. (d, e) Cross-sectional images, obtained in the planes shown in b, show asymmetric high attenuation where the layers of metal overlap, both proximal to the bifurcation (d) and across the ostium of the side-branch vessel (e).
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Figure 11d. Crush stent placement at the circumflex-marginal artery bifurcation. (a, b) Volume-rendered image (a) and curved multiplanar reformatted image (b) allow assessment of the stent configuration. (c) Diagram shows the multiple layers of metal that produce an asymmetric appearance of the cross-sectional stent profile. (d, e) Cross-sectional images, obtained in the planes shown in b, show asymmetric high attenuation where the layers of metal overlap, both proximal to the bifurcation (d) and across the ostium of the side-branch vessel (e).
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Figure 11e. Crush stent placement at the circumflex-marginal artery bifurcation. (a, b) Volume-rendered image (a) and curved multiplanar reformatted image (b) allow assessment of the stent configuration. (c) Diagram shows the multiple layers of metal that produce an asymmetric appearance of the cross-sectional stent profile. (d, e) Cross-sectional images, obtained in the planes shown in b, show asymmetric high attenuation where the layers of metal overlap, both proximal to the bifurcation (d) and across the ostium of the side-branch vessel (e).
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Copyright © 2006 by the Radiological Society of North America.
