DOI: 10.1148/rg.255055014
Quantitative Vascular Measurements in Arterial Occlusive Disease1
Hideki Ota, MD,
Kei Takase, MD,
Hiroya Rikimaru, MD,
Masahiro Tsuboi, MD,
Takayuki Yamada, MD,
Akihiro Sato, MD,
Shuichi Higano, MD,
Tadashi Ishibashi, MD and
Shoki Takahashi, MD
1 From the Department of Diagnostic Radiology, Tokohu University Graduate School of Medicine, 1–1 Seiryo, Aoba, Sendai, Japan (H.O., K.T., T.Y., A.S., S.H., T.I., S.T.); the Department of Radiology, Ishinomaki Red Cross Hospital, Ishinomaki, Miyagi, Japan (H.R.); and the Department of Radiology, Furukawa City Hospital, Furukawa, Miyagi, Japan (M.T.). Presented as an education exhibit at the 2004 RSNA Annual Meeting. Received January 28, 2005; revision requested March 10 and received April 21; accepted April 22. All authors have no financial relationships to disclose.
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Figure 1. Drawing illustrates measurements used to determine the degree of vascular stenosis. Rp and Rd indicate the luminal diameter or area in the normal-looking portion of the vessel proximal (Rp) and distal (Rd) to the stenotic lesion (L). Re is the estimated luminal diameter or area at the level of the lesion. Any of these values—Rp, Rd, or Re—can be used as the reference value, and it should be noted which of the three is used. The percentage of stenosis is calculated as (1 – L/R) x 100, where L = lesion diameter or area and R = diameter or area at the reference site.
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Figure 2. Drawings illustrate how projection images (a, b) and a cross-sectional image (c) are used to measure the diameter of an eccentric arterial stenosis. In a, the minimum luminal diameter (Da) is depicted at the optimal projection angle. In b, the degree of stenosis is underestimated because the minimum luminal diameter (Db) is depicted at a suboptimal projection angle, making it larger than Da. The cross-sectional image is oriented perpendicular to the vessel and accurately depicts lumen morphology, making the minimum luminal diameter easy to measure. Da and Db in c correspond to the diameters measured in a and b.
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Figure 3. Graph (top) illustrates the relationship between area reduction and diameter reduction in a completely concentric stenosis. The relationship is described by the equation A = D x (2 – [D/100]), where A = percentage of area reduction and D = percentage of diameter reduction. Drawings at bottom illustrate cross-sectional views of lumina at various percentages of area and diameter stenosis.
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Figure 4a. Stenoses of the left external and right common iliac arteries in a 70-year-old woman. (a) Anteroposterior DSA image fails to depict stenosis of the left external iliac artery because of the enhancement of the overlying left internal iliac artery (straight arrow). However, stenosis of the right common iliac artery can be seen (curved arrow). (b) DSA image (30° right anterior oblique angle) allows differentiation of the enhanced left external iliac artery from the left internal iliac artery, demonstrating 60% diameter stenosis of the former artery (arrow) relative to the distal reference site (arrowhead).
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Figure 4b. Stenoses of the left external and right common iliac arteries in a 70-year-old woman. (a) Anteroposterior DSA image fails to depict stenosis of the left external iliac artery because of the enhancement of the overlying left internal iliac artery (straight arrow). However, stenosis of the right common iliac artery can be seen (curved arrow). (b) DSA image (30° right anterior oblique angle) allows differentiation of the enhanced left external iliac artery from the left internal iliac artery, demonstrating 60% diameter stenosis of the former artery (arrow) relative to the distal reference site (arrowhead).
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Figure 5a. (a) Drawing illustrates a tortuous vessel with upper concentric stenosis with surrounding mural calcification and lower eccentric stenosis with partial calcification. The two planes oriented perpendicular to the vessel indicate the levels at which cross-sectional images were obtained. The curved plane oriented longitudinally along the vessel indicates the cutting plane of the CPR image (cf e). (b) Drawings illustrate cross-sectional images (cf a), which accurately depict luminal configurations and mural calcifications, thereby allowing measurement of both diameter stenosis and area stenosis. (c) Drawing illustrates a VR image that provides a comprehensive overview of the vessel. The upper stenosis is partially hidden by mural calcification. (d) Drawing illustrates an MIP image; overlying mural calcification makes evaluation of the upper stenosis impossible. (e) Drawing illustrates a CPR image that depicts the upper stenosis with part of the surrounding mural calcification as well as the lower stenosis.
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Figure 5b. (a) Drawing illustrates a tortuous vessel with upper concentric stenosis with surrounding mural calcification and lower eccentric stenosis with partial calcification. The two planes oriented perpendicular to the vessel indicate the levels at which cross-sectional images were obtained. The curved plane oriented longitudinally along the vessel indicates the cutting plane of the CPR image (cf e). (b) Drawings illustrate cross-sectional images (cf a), which accurately depict luminal configurations and mural calcifications, thereby allowing measurement of both diameter stenosis and area stenosis. (c) Drawing illustrates a VR image that provides a comprehensive overview of the vessel. The upper stenosis is partially hidden by mural calcification. (d) Drawing illustrates an MIP image; overlying mural calcification makes evaluation of the upper stenosis impossible. (e) Drawing illustrates a CPR image that depicts the upper stenosis with part of the surrounding mural calcification as well as the lower stenosis.
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Figure 5c. (a) Drawing illustrates a tortuous vessel with upper concentric stenosis with surrounding mural calcification and lower eccentric stenosis with partial calcification. The two planes oriented perpendicular to the vessel indicate the levels at which cross-sectional images were obtained. The curved plane oriented longitudinally along the vessel indicates the cutting plane of the CPR image (cf e). (b) Drawings illustrate cross-sectional images (cf a), which accurately depict luminal configurations and mural calcifications, thereby allowing measurement of both diameter stenosis and area stenosis. (c) Drawing illustrates a VR image that provides a comprehensive overview of the vessel. The upper stenosis is partially hidden by mural calcification. (d) Drawing illustrates an MIP image; overlying mural calcification makes evaluation of the upper stenosis impossible. (e) Drawing illustrates a CPR image that depicts the upper stenosis with part of the surrounding mural calcification as well as the lower stenosis.
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Figure 5d. (a) Drawing illustrates a tortuous vessel with upper concentric stenosis with surrounding mural calcification and lower eccentric stenosis with partial calcification. The two planes oriented perpendicular to the vessel indicate the levels at which cross-sectional images were obtained. The curved plane oriented longitudinally along the vessel indicates the cutting plane of the CPR image (cf e). (b) Drawings illustrate cross-sectional images (cf a), which accurately depict luminal configurations and mural calcifications, thereby allowing measurement of both diameter stenosis and area stenosis. (c) Drawing illustrates a VR image that provides a comprehensive overview of the vessel. The upper stenosis is partially hidden by mural calcification. (d) Drawing illustrates an MIP image; overlying mural calcification makes evaluation of the upper stenosis impossible. (e) Drawing illustrates a CPR image that depicts the upper stenosis with part of the surrounding mural calcification as well as the lower stenosis.
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Figure 5e. (a) Drawing illustrates a tortuous vessel with upper concentric stenosis with surrounding mural calcification and lower eccentric stenosis with partial calcification. The two planes oriented perpendicular to the vessel indicate the levels at which cross-sectional images were obtained. The curved plane oriented longitudinally along the vessel indicates the cutting plane of the CPR image (cf e). (b) Drawings illustrate cross-sectional images (cf a), which accurately depict luminal configurations and mural calcifications, thereby allowing measurement of both diameter stenosis and area stenosis. (c) Drawing illustrates a VR image that provides a comprehensive overview of the vessel. The upper stenosis is partially hidden by mural calcification. (d) Drawing illustrates an MIP image; overlying mural calcification makes evaluation of the upper stenosis impossible. (e) Drawing illustrates a CPR image that depicts the upper stenosis with part of the surrounding mural calcification as well as the lower stenosis.
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Figure 6a. Stenosis of the right external iliac artery in a 70-year-old man. The reformatted images in a–f were generated from multi–detector row CT data obtained with semiautomated software (Advanced Vessel Analysis, GE Medical Systems) for vascular analysis. (a) VR image provides an overview of the stenotic artery. The black line connects the midpoints of the cross-sectional vascular lumen and is drawn automatically after the starting point and endpoint of the target vessel have been plotted. Lines b–d indicate the levels at which cross-sectional MPR images were obtained. (b–d) Cross-sectional MPR images obtained at different levels (cf lines b–d in a) demonstrate varying degrees of luminal enhancement (arrowhead). Both luminal diameter and area (shown as percentages) were calculated automatically after level d had been chosen as the reference site. (e) Stretched CPR image (left) shows the target vessel. Diagram (right) shows the calculated luminal area throughout the vessel (gray area). Lines b–d indicate the levels at which the cross-sectional images were obtained (cf b–d), with the corresponding area measurements given in square millimeters. (f ) CPR image shows the distribution of plaques and calcifications in the vessel (arrows), together with stenoses. (g) DSA image demonstrates 60% diameter stenosis in the proximal external iliac artery (b) and 70% diameter stenosis in the distal external iliac artery (c). Line d indicates the reference site.
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Figure 6b. Stenosis of the right external iliac artery in a 70-year-old man. The reformatted images in a–f were generated from multi–detector row CT data obtained with semiautomated software (Advanced Vessel Analysis, GE Medical Systems) for vascular analysis. (a) VR image provides an overview of the stenotic artery. The black line connects the midpoints of the cross-sectional vascular lumen and is drawn automatically after the starting point and endpoint of the target vessel have been plotted. Lines b–d indicate the levels at which cross-sectional MPR images were obtained. (b–d) Cross-sectional MPR images obtained at different levels (cf lines b–d in a) demonstrate varying degrees of luminal enhancement (arrowhead). Both luminal diameter and area (shown as percentages) were calculated automatically after level d had been chosen as the reference site. (e) Stretched CPR image (left) shows the target vessel. Diagram (right) shows the calculated luminal area throughout the vessel (gray area). Lines b–d indicate the levels at which the cross-sectional images were obtained (cf b–d), with the corresponding area measurements given in square millimeters. (f ) CPR image shows the distribution of plaques and calcifications in the vessel (arrows), together with stenoses. (g) DSA image demonstrates 60% diameter stenosis in the proximal external iliac artery (b) and 70% diameter stenosis in the distal external iliac artery (c). Line d indicates the reference site.
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Figure 6c. Stenosis of the right external iliac artery in a 70-year-old man. The reformatted images in a–f were generated from multi–detector row CT data obtained with semiautomated software (Advanced Vessel Analysis, GE Medical Systems) for vascular analysis. (a) VR image provides an overview of the stenotic artery. The black line connects the midpoints of the cross-sectional vascular lumen and is drawn automatically after the starting point and endpoint of the target vessel have been plotted. Lines b–d indicate the levels at which cross-sectional MPR images were obtained. (b–d) Cross-sectional MPR images obtained at different levels (cf lines b–d in a) demonstrate varying degrees of luminal enhancement (arrowhead). Both luminal diameter and area (shown as percentages) were calculated automatically after level d had been chosen as the reference site. (e) Stretched CPR image (left) shows the target vessel. Diagram (right) shows the calculated luminal area throughout the vessel (gray area). Lines b–d indicate the levels at which the cross-sectional images were obtained (cf b–d), with the corresponding area measurements given in square millimeters. (f ) CPR image shows the distribution of plaques and calcifications in the vessel (arrows), together with stenoses. (g) DSA image demonstrates 60% diameter stenosis in the proximal external iliac artery (b) and 70% diameter stenosis in the distal external iliac artery (c). Line d indicates the reference site.
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Figure 6d. Stenosis of the right external iliac artery in a 70-year-old man. The reformatted images in a–f were generated from multi–detector row CT data obtained with semiautomated software (Advanced Vessel Analysis, GE Medical Systems) for vascular analysis. (a) VR image provides an overview of the stenotic artery. The black line connects the midpoints of the cross-sectional vascular lumen and is drawn automatically after the starting point and endpoint of the target vessel have been plotted. Lines b–d indicate the levels at which cross-sectional MPR images were obtained. (b–d) Cross-sectional MPR images obtained at different levels (cf lines b–d in a) demonstrate varying degrees of luminal enhancement (arrowhead). Both luminal diameter and area (shown as percentages) were calculated automatically after level d had been chosen as the reference site. (e) Stretched CPR image (left) shows the target vessel. Diagram (right) shows the calculated luminal area throughout the vessel (gray area). Lines b–d indicate the levels at which the cross-sectional images were obtained (cf b–d), with the corresponding area measurements given in square millimeters. (f ) CPR image shows the distribution of plaques and calcifications in the vessel (arrows), together with stenoses. (g) DSA image demonstrates 60% diameter stenosis in the proximal external iliac artery (b) and 70% diameter stenosis in the distal external iliac artery (c). Line d indicates the reference site.
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Figure 6e. Stenosis of the right external iliac artery in a 70-year-old man. The reformatted images in a–f were generated from multi–detector row CT data obtained with semiautomated software (Advanced Vessel Analysis, GE Medical Systems) for vascular analysis. (a) VR image provides an overview of the stenotic artery. The black line connects the midpoints of the cross-sectional vascular lumen and is drawn automatically after the starting point and endpoint of the target vessel have been plotted. Lines b–d indicate the levels at which cross-sectional MPR images were obtained. (b–d) Cross-sectional MPR images obtained at different levels (cf lines b–d in a) demonstrate varying degrees of luminal enhancement (arrowhead). Both luminal diameter and area (shown as percentages) were calculated automatically after level d had been chosen as the reference site. (e) Stretched CPR image (left) shows the target vessel. Diagram (right) shows the calculated luminal area throughout the vessel (gray area). Lines b–d indicate the levels at which the cross-sectional images were obtained (cf b–d), with the corresponding area measurements given in square millimeters. (f ) CPR image shows the distribution of plaques and calcifications in the vessel (arrows), together with stenoses. (g) DSA image demonstrates 60% diameter stenosis in the proximal external iliac artery (b) and 70% diameter stenosis in the distal external iliac artery (c). Line d indicates the reference site.
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Figure 6f. Stenosis of the right external iliac artery in a 70-year-old man. The reformatted images in a–f were generated from multi–detector row CT data obtained with semiautomated software (Advanced Vessel Analysis, GE Medical Systems) for vascular analysis. (a) VR image provides an overview of the stenotic artery. The black line connects the midpoints of the cross-sectional vascular lumen and is drawn automatically after the starting point and endpoint of the target vessel have been plotted. Lines b–d indicate the levels at which cross-sectional MPR images were obtained. (b–d) Cross-sectional MPR images obtained at different levels (cf lines b–d in a) demonstrate varying degrees of luminal enhancement (arrowhead). Both luminal diameter and area (shown as percentages) were calculated automatically after level d had been chosen as the reference site. (e) Stretched CPR image (left) shows the target vessel. Diagram (right) shows the calculated luminal area throughout the vessel (gray area). Lines b–d indicate the levels at which the cross-sectional images were obtained (cf b–d), with the corresponding area measurements given in square millimeters. (f ) CPR image shows the distribution of plaques and calcifications in the vessel (arrows), together with stenoses. (g) DSA image demonstrates 60% diameter stenosis in the proximal external iliac artery (b) and 70% diameter stenosis in the distal external iliac artery (c). Line d indicates the reference site.
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Figure 6g. Stenosis of the right external iliac artery in a 70-year-old man. The reformatted images in a–f were generated from multi–detector row CT data obtained with semiautomated software (Advanced Vessel Analysis, GE Medical Systems) for vascular analysis. (a) VR image provides an overview of the stenotic artery. The black line connects the midpoints of the cross-sectional vascular lumen and is drawn automatically after the starting point and endpoint of the target vessel have been plotted. Lines b–d indicate the levels at which cross-sectional MPR images were obtained. (b–d) Cross-sectional MPR images obtained at different levels (cf lines b–d in a) demonstrate varying degrees of luminal enhancement (arrowhead). Both luminal diameter and area (shown as percentages) were calculated automatically after level d had been chosen as the reference site. (e) Stretched CPR image (left) shows the target vessel. Diagram (right) shows the calculated luminal area throughout the vessel (gray area). Lines b–d indicate the levels at which the cross-sectional images were obtained (cf b–d), with the corresponding area measurements given in square millimeters. (f ) CPR image shows the distribution of plaques and calcifications in the vessel (arrows), together with stenoses. (g) DSA image demonstrates 60% diameter stenosis in the proximal external iliac artery (b) and 70% diameter stenosis in the distal external iliac artery (c). Line d indicates the reference site.
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Figure 7a. Bilateral renal artery stenoses in a 58-year-old man. Multi–detector row CT was performed following stent placement. (a) MIP image depicts bilateral indwelling stents in the renal arteries. However, it is impossible to evaluate the patency of the lumen within the stents. (b) Curved MPR image generated along the central line of the bilateral renal arteries clearly depicts luminal patency within the stents.
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Figure 7b. Bilateral renal artery stenoses in a 58-year-old man. Multi–detector row CT was performed following stent placement. (a) MIP image depicts bilateral indwelling stents in the renal arteries. However, it is impossible to evaluate the patency of the lumen within the stents. (b) Curved MPR image generated along the central line of the bilateral renal arteries clearly depicts luminal patency within the stents.
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Figure 8a. Stenosis of the left common iliac artery in a 74-year-old man. (a) MIP image from multi–detector row CT data depicts severe bilateral calcifications in the iliac arteries. The degree of luminal stenosis is not assessable at any calcified site. (b) Cross-sectional image of the left external iliac artery from multi–detector row CT data is suspicious for luminal stenosis (arrow). However, evaluation of the degree of stenosis is difficult even after setting the window width and level due to beam-hardening artifact from the severe calcification. (c) MIP image from contrast-enhanced MR angiographic data obtained at 30° right anterior and caudal oblique angles demonstrates 60% diameter stenosis of the left common iliac artery (arrow).
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Figure 8b. Stenosis of the left common iliac artery in a 74-year-old man. (a) MIP image from multi–detector row CT data depicts severe bilateral calcifications in the iliac arteries. The degree of luminal stenosis is not assessable at any calcified site. (b) Cross-sectional image of the left external iliac artery from multi–detector row CT data is suspicious for luminal stenosis (arrow). However, evaluation of the degree of stenosis is difficult even after setting the window width and level due to beam-hardening artifact from the severe calcification. (c) MIP image from contrast-enhanced MR angiographic data obtained at 30° right anterior and caudal oblique angles demonstrates 60% diameter stenosis of the left common iliac artery (arrow).
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Figure 8c. Stenosis of the left common iliac artery in a 74-year-old man. (a) MIP image from multi–detector row CT data depicts severe bilateral calcifications in the iliac arteries. The degree of luminal stenosis is not assessable at any calcified site. (b) Cross-sectional image of the left external iliac artery from multi–detector row CT data is suspicious for luminal stenosis (arrow). However, evaluation of the degree of stenosis is difficult even after setting the window width and level due to beam-hardening artifact from the severe calcification. (c) MIP image from contrast-enhanced MR angiographic data obtained at 30° right anterior and caudal oblique angles demonstrates 60% diameter stenosis of the left common iliac artery (arrow).
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Figure 9a. Mild stenosis of the right renal artery in a 62-year-old woman. (a) Contrast-enhanced MR angiogram shows 70% diameter stenosis of the right renal artery. (b) DSA image obtained during transcatheter measurement of arterial pressure shows only mild (45%) diameter stenosis. In addition, there was no significant pressure gradient in the artery. These findings prevented unwarranted intervention.
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Figure 9b. Mild stenosis of the right renal artery in a 62-year-old woman. (a) Contrast-enhanced MR angiogram shows 70% diameter stenosis of the right renal artery. (b) DSA image obtained during transcatheter measurement of arterial pressure shows only mild (45%) diameter stenosis. In addition, there was no significant pressure gradient in the artery. These findings prevented unwarranted intervention.
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Figure 11. Drawing illustrates the changes in blood flow caused by a stenosis. The peak systolic velocity (PSV) in the proximal nonstenotic lumen (Vp) is normal. At the stenosis, flow velocity increases as the blood passes through the restricted area. The ratio between the PSV at the stenosis (Vs) and Vp is used to evaluate the degree of stenosis. A jet is observed in the poststenotic lumen, with subsequent turbulent flow near the vessel wall in cases of severe stenosis.
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Figure 12a. Intravascular US images of a peripheral artery show the residual lumen as an anechoic area (dotted circle in b). The outer echolucent layer (dashed circle in b) represents the media, the relatively echogenic area between the circles represents thickened intima containing plaque, and the echogenic area outside the dashed circle represents the adventitia and periadventitial tissues.
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Figure 12b. Intravascular US images of a peripheral artery show the residual lumen as an anechoic area (dotted circle in b). The outer echolucent layer (dashed circle in b) represents the media, the relatively echogenic area between the circles represents thickened intima containing plaque, and the echogenic area outside the dashed circle represents the adventitia and periadventitial tissues.
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Figure 13. Drawing illustrates how the percentage of diameter stenosis in an ICA is measured in the NASCET and the ESCT. The NASCET uses the formula 1 – (a/c), where a is the residual luminal diameter at the stenosis and c is the luminal diameter at a visible, disease-free point above the stenosis. The ECST uses the formula 1 – (a/b), where b is the estimated luminal diameter at the level of the lesion based on a visual impression of where the normal arterial wall was before development of the stenosis. CCA = common carotid artery, ECA = external carotid artery.
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Figure 14a. Stenosis of the left ICA in a 59-year-old man. (a) Color Doppler flow US image shows more than 50% stenosis caused by plaques at the origin of the ICA. (b) Duplex US image shows a PSV of 296 cm/sec, a finding that indicates a stenosis of at least 70%. (c) MIP image from multi–detector row CT data shows the levels at which cross-sectional images were obtained (d, e). (d, e) Cross-sectional images obtained at the stenotic site (d) and the reference site (e) demonstrate 70% diameter stenosis and 90% area stenosis. (f ) DSA image shows 70% diameter stenosis (as measured with NASCET criteria).
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Figure 14b. Stenosis of the left ICA in a 59-year-old man. (a) Color Doppler flow US image shows more than 50% stenosis caused by plaques at the origin of the ICA. (b) Duplex US image shows a PSV of 296 cm/sec, a finding that indicates a stenosis of at least 70%. (c) MIP image from multi–detector row CT data shows the levels at which cross-sectional images were obtained (d, e). (d, e) Cross-sectional images obtained at the stenotic site (d) and the reference site (e) demonstrate 70% diameter stenosis and 90% area stenosis. (f ) DSA image shows 70% diameter stenosis (as measured with NASCET criteria).
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Figure 14c. Stenosis of the left ICA in a 59-year-old man. (a) Color Doppler flow US image shows more than 50% stenosis caused by plaques at the origin of the ICA. (b) Duplex US image shows a PSV of 296 cm/sec, a finding that indicates a stenosis of at least 70%. (c) MIP image from multi–detector row CT data shows the levels at which cross-sectional images were obtained (d, e). (d, e) Cross-sectional images obtained at the stenotic site (d) and the reference site (e) demonstrate 70% diameter stenosis and 90% area stenosis. (f ) DSA image shows 70% diameter stenosis (as measured with NASCET criteria).
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Figure 14d. Stenosis of the left ICA in a 59-year-old man. (a) Color Doppler flow US image shows more than 50% stenosis caused by plaques at the origin of the ICA. (b) Duplex US image shows a PSV of 296 cm/sec, a finding that indicates a stenosis of at least 70%. (c) MIP image from multi–detector row CT data shows the levels at which cross-sectional images were obtained (d, e). (d, e) Cross-sectional images obtained at the stenotic site (d) and the reference site (e) demonstrate 70% diameter stenosis and 90% area stenosis. (f ) DSA image shows 70% diameter stenosis (as measured with NASCET criteria).
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Figure 14e. Stenosis of the left ICA in a 59-year-old man. (a) Color Doppler flow US image shows more than 50% stenosis caused by plaques at the origin of the ICA. (b) Duplex US image shows a PSV of 296 cm/sec, a finding that indicates a stenosis of at least 70%. (c) MIP image from multi–detector row CT data shows the levels at which cross-sectional images were obtained (d, e). (d, e) Cross-sectional images obtained at the stenotic site (d) and the reference site (e) demonstrate 70% diameter stenosis and 90% area stenosis. (f ) DSA image shows 70% diameter stenosis (as measured with NASCET criteria).
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Figure 14f. Stenosis of the left ICA in a 59-year-old man. (a) Color Doppler flow US image shows more than 50% stenosis caused by plaques at the origin of the ICA. (b) Duplex US image shows a PSV of 296 cm/sec, a finding that indicates a stenosis of at least 70%. (c) MIP image from multi–detector row CT data shows the levels at which cross-sectional images were obtained (d, e). (d, e) Cross-sectional images obtained at the stenotic site (d) and the reference site (e) demonstrate 70% diameter stenosis and 90% area stenosis. (f ) DSA image shows 70% diameter stenosis (as measured with NASCET criteria).
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Figure 15a. Left renal artery stenosis in a 65-year-old woman. (a) Duplex US image shows a PSV of 328 cm/sec in the left renal artery, a finding that suggests significant stenosis. (b) VR image (20° left anterior oblique angle) from multi–detector row CT data shows the levels at which cross-sectional images were obtained (c, d). (c, d) Cross-sectional images demonstrate a stenosis (c) causing 62% diameter reduction and 85% area reduction relative to the reference site (d). (e) DSA image (20° left anterior oblique angle) obtained prior to angioplasty shows 65% diameter stenosis in the left main renal artery. (f, g) Intravascular US images obtained at the stenotic site (f ) and the distal reference site (g) show 60% diameter stenosis and 80% area stenosis with thick plaque (red-orange area).
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Figure 15b. Left renal artery stenosis in a 65-year-old woman. (a) Duplex US image shows a PSV of 328 cm/sec in the left renal artery, a finding that suggests significant stenosis. (b) VR image (20° left anterior oblique angle) from multi–detector row CT data shows the levels at which cross-sectional images were obtained (c, d). (c, d) Cross-sectional images demonstrate a stenosis (c) causing 62% diameter reduction and 85% area reduction relative to the reference site (d). (e) DSA image (20° left anterior oblique angle) obtained prior to angioplasty shows 65% diameter stenosis in the left main renal artery. (f, g) Intravascular US images obtained at the stenotic site (f ) and the distal reference site (g) show 60% diameter stenosis and 80% area stenosis with thick plaque (red-orange area).
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Figure 15c. Left renal artery stenosis in a 65-year-old woman. (a) Duplex US image shows a PSV of 328 cm/sec in the left renal artery, a finding that suggests significant stenosis. (b) VR image (20° left anterior oblique angle) from multi–detector row CT data shows the levels at which cross-sectional images were obtained (c, d). (c, d) Cross-sectional images demonstrate a stenosis (c) causing 62% diameter reduction and 85% area reduction relative to the reference site (d). (e) DSA image (20° left anterior oblique angle) obtained prior to angioplasty shows 65% diameter stenosis in the left main renal artery. (f, g) Intravascular US images obtained at the stenotic site (f ) and the distal reference site (g) show 60% diameter stenosis and 80% area stenosis with thick plaque (red-orange area).
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Figure 15d. Left renal artery stenosis in a 65-year-old woman. (a) Duplex US image shows a PSV of 328 cm/sec in the left renal artery, a finding that suggests significant stenosis. (b) VR image (20° left anterior oblique angle) from multi–detector row CT data shows the levels at which cross-sectional images were obtained (c, d). (c, d) Cross-sectional images demonstrate a stenosis (c) causing 62% diameter reduction and 85% area reduction relative to the reference site (d). (e) DSA image (20° left anterior oblique angle) obtained prior to angioplasty shows 65% diameter stenosis in the left main renal artery. (f, g) Intravascular US images obtained at the stenotic site (f ) and the distal reference site (g) show 60% diameter stenosis and 80% area stenosis with thick plaque (red-orange area).
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Figure 15e. Left renal artery stenosis in a 65-year-old woman. (a) Duplex US image shows a PSV of 328 cm/sec in the left renal artery, a finding that suggests significant stenosis. (b) VR image (20° left anterior oblique angle) from multi–detector row CT data shows the levels at which cross-sectional images were obtained (c, d). (c, d) Cross-sectional images demonstrate a stenosis (c) causing 62% diameter reduction and 85% area reduction relative to the reference site (d). (e) DSA image (20° left anterior oblique angle) obtained prior to angioplasty shows 65% diameter stenosis in the left main renal artery. (f, g) Intravascular US images obtained at the stenotic site (f ) and the distal reference site (g) show 60% diameter stenosis and 80% area stenosis with thick plaque (red-orange area).
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Figure 15f. Left renal artery stenosis in a 65-year-old woman. (a) Duplex US image shows a PSV of 328 cm/sec in the left renal artery, a finding that suggests significant stenosis. (b) VR image (20° left anterior oblique angle) from multi–detector row CT data shows the levels at which cross-sectional images were obtained (c, d). (c, d) Cross-sectional images demonstrate a stenosis (c) causing 62% diameter reduction and 85% area reduction relative to the reference site (d). (e) DSA image (20° left anterior oblique angle) obtained prior to angioplasty shows 65% diameter stenosis in the left main renal artery. (f, g) Intravascular US images obtained at the stenotic site (f ) and the distal reference site (g) show 60% diameter stenosis and 80% area stenosis with thick plaque (red-orange area).
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Figure 15g. Left renal artery stenosis in a 65-year-old woman. (a) Duplex US image shows a PSV of 328 cm/sec in the left renal artery, a finding that suggests significant stenosis. (b) VR image (20° left anterior oblique angle) from multi–detector row CT data shows the levels at which cross-sectional images were obtained (c, d). (c, d) Cross-sectional images demonstrate a stenosis (c) causing 62% diameter reduction and 85% area reduction relative to the reference site (d). (e) DSA image (20° left anterior oblique angle) obtained prior to angioplasty shows 65% diameter stenosis in the left main renal artery. (f, g) Intravascular US images obtained at the stenotic site (f ) and the distal reference site (g) show 60% diameter stenosis and 80% area stenosis with thick plaque (red-orange area).
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Figure 16a. Occlusion of the right iliac artery in a 72-year-old man. (a) Coronal CPR image from multi–detector row CT angiographic data shows the right iliac artery with a 7-cm-long occluded segment (arrows), a finding that allowed planning of vascular intervention. (b) DSA image shows occlusion of the right iliac artery but provides no information about the occluded segment. The segment distal to the occlusion is faintly enhanced (arrow). (c) DSA image obtained just after stent placement shows revascularization of the artery.
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Figure 16b. Occlusion of the right iliac artery in a 72-year-old man. (a) Coronal CPR image from multi–detector row CT angiographic data shows the right iliac artery with a 7-cm-long occluded segment (arrows), a finding that allowed planning of vascular intervention. (b) DSA image shows occlusion of the right iliac artery but provides no information about the occluded segment. The segment distal to the occlusion is faintly enhanced (arrow). (c) DSA image obtained just after stent placement shows revascularization of the artery.
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Figure 16c. Occlusion of the right iliac artery in a 72-year-old man. (a) Coronal CPR image from multi–detector row CT angiographic data shows the right iliac artery with a 7-cm-long occluded segment (arrows), a finding that allowed planning of vascular intervention. (b) DSA image shows occlusion of the right iliac artery but provides no information about the occluded segment. The segment distal to the occlusion is faintly enhanced (arrow). (c) DSA image obtained just after stent placement shows revascularization of the artery.
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Figure 17a. Peripheral arterial occlusive disease in a 70-year-old man. (a) MIP image from multi–detector row CT angiographic data obtained with the usual protocol shows insufficient bilateral enhancement of the calf arteries because of excessive table speed relative to blood flow velocity. Because this insufficient enhancement was noticed at real-time monitoring, additional scanning was performed to evaluate the infrapopliteal arteries. (b) MIP image from data obtained during scanning of the infrapopliteal arteries shows sufficient luminal enhancement of the calf arteries. Note the bilateral occlusion of the peroneal arteries.
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Figure 17b. Peripheral arterial occlusive disease in a 70-year-old man. (a) MIP image from multi–detector row CT angiographic data obtained with the usual protocol shows insufficient bilateral enhancement of the calf arteries because of excessive table speed relative to blood flow velocity. Because this insufficient enhancement was noticed at real-time monitoring, additional scanning was performed to evaluate the infrapopliteal arteries. (b) MIP image from data obtained during scanning of the infrapopliteal arteries shows sufficient luminal enhancement of the calf arteries. Note the bilateral occlusion of the peroneal arteries.
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Copyright © 2005 by the Radiological Society of North America.
) between the ultrasound beam and the direction of blood flow, either relatively narrow (
60°) or wider (
f ) and blood flow velocity is described by the equation 
1540 m/sec). (b) Graph illustrates the relationship between blood flow velocity and incident angle when the measured value of Doppler shift (