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6.3 · Atlas: Visceral andRetroperitoneal Vessels
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. Fig. 6.55a–d (Atlas) High-grade mesenteric artery stenosis.
a Aliasing in the color mode suggests high-grade stenosis at the origin of the superior mesenteric artery. The scanning conditions are usually
good in the very thin patients presenting with suspected abdominal angina, but the arched course of the superior mesenteric artery at its origin
may impair adequate angulation of the Doppler beam (left image). In inspiration, this segment of the superior mesenteric artery is straightened,
which facilitates adjustment of the angle correction cursor parallel to the vessel wall and reduces the angle setting error (compare gray-scale
image and color duplex image).
b The Doppler waveform from the distal mesenteric branches (such as the ileocolic artery) shows the typical features of postocclusive ow with a
markedly reduced pulsatility and an almost venous prole.
c The inferior mesenteric artery acts as a collateral via the Riolan anastomosis and hence shows an increased ow velocity, in particular in diastole.
d Sonographic follow-up after 2months identies the stent as a mesh-like structure in the wall area of the superior mesenteric artery. The Doppler
waveform is characterized by a high-frequency signal with an angle-corrected PSV of over 8m/s indicating high-grade restenosis
ab
. Fig. 6.56a–d (Atlas) Acute mesenteric artery occlusion.
a Patient presenting with acute abdomen. An abnormal Doppler waveform is obtained from the origin of the superior mesenteric artery with a
decreased peak systolic velocity (PSV) of 39cm/s. End-diastolic velocity (EDV) is 7.2cm/s; the Pourcelot index is reduced.
b Continuous scanning of the superior mesenteric artery starting at its origin yields a ow prole more and more resembling a thump pattern with
a decreasing ow velocity and absence of end-diastolic ow close to the occlusion. Flow in the mesenteric artery is toward the transducer and displayed above the baseline. The frequencies displayed below the baseline are from the middle colic artery, which arises near the sample volume.
c More distally, the superior mesenteric artery is occluded with zero ow in the Doppler waveform despite a high gain.
d Angiogram showing patency of the trunk of the superior mesenteric artery and occlusion distal to the origin of the middle colic artery
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Chapter 6 · Visceral andRetroperitoneal Vessels
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. Fig. 6.57a–f (Atlas) Acute mesenteric artery occlusion.
a 42-year-old patient presenting with a 3-h history of severe abdominal pain, in part of a cramping nature. No abnormal laboratory values at this time
(no leukocytosis, no acidosis, no elevated lactate level). The clinical examination reveals only mild tenderness, absence of peritonism, and diuse
abdominal pain. Normal B-mode ultrasound and radiologic examinations. No history of cardiac disease. Patient admitted to hospital in the evening
with the tentative diagnosis of enteritis; analgesic therapy and follow-up contemplated. Additionally performed duplex ultrasound of the mesenteric
arteries demonstrates an abnormal signal at the origin of the patent superior mesenteric artery. Peak systolic velocity (PSV) is markedly reduced to
37.2cm/s with a relatively large diastolic component of 15.2cm/s, resulting in an abnormal resistance index of 0.59.
b More distally, downstream of the origin of the middle colic artery, the Doppler waveform of the mesenteric artery shows a thump pattern.
c Color duplex imaging demonstrates a patent superior mesenteric artery to the level of the origins of the rst jejunal branches. A proximal jejunal
branch also shows color-coded ow signals. In the remainder of the superior mesenteric artery, neither color duplex nor spectral Doppler depicts ow
signals. Emergency embolectomy with complete revascularization was performed without the necessity for bowel resection.
Mesenteric artery occlusion– acute versus chronic.
d A slim 82-year-old woman with a history of intermittent abdominal pain was hospitalized for severe abdominal pain. On admission, she had a regular
heart rate of 95 beats/min but a history of embolectomy of the leg in the year before. The color duplex examination reveals occlusion of the proximal
superior mesenteric artery segment from its origin to the level of the pancreaticoduodenal artery origin (K). The superior mesenteric artery (A.M.S) is
relled by the gastroduodenal artery (arising from the hepatic artery) and the pancreaticoduodenal artery (K). With the gastroduodenal artery acting
as a collateral (KOL in the second image), ow in this artery is high and clearly visualized. The spectral Doppler recording with the sample volume in
this artery reveals a PSV of 220cm/s and an end-diastolic velocity (EDV) of 100cm/s. These color duplex ndings are consistent with chronic occlusion.
e With the sample volume placed in the superior mesenteric artery (A.M.S.), very low ow velocities of 31cm/s during systole and 12cm/s at end diastole are measured, suggesting poor collateralization or poor peripheral outow.
f With the transducer in transverse orientation on the upper abdomen, the mesenteric artery trunk is examined in the color duplex mode with a low
pulse repetition frequency, evaluating the jejunal origins for patency. Following the mesenteric artery downward, three jejunal branches are identied
(A.J; left image) before the artery (A.M.S) rst becomes partially occluded and then, more distally, completely occluded (no ow; right image). A jejunal
vein branch (V.J) entering the mesenteric vein (V.M.S) is seen between the mesenteric artery anteriorly and the aorta (A) posteriorly. Taking these
additional ndings into account, the overall situation suggests acute embolic occlusion rather than chronic occlusion– despite the conclusion suggested by the ndings described in d. Intraoperatively, a short embolic occlusion at the mesenteric artery origin from the aorta was seen and a second
occlusion of the distal segment with some patent jejunal branches arising from the patent portion between these occlusions. The patent portion was
supplied by the pancreaticoduodenal artery (as demonstrated by the sonographic examination)
6.3 · Atlas: Visceral andRetroperitoneal Vessels
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. Fig. 6.58a–c (Atlas) Chronic mesenteric artery occlusion.
a 50-year-old patient with symptoms of abdominal angina caused by proximal occlusion of the superior mesenteric artery with relling through
the gastroduodenal and pancreaticoduodenal arteries about 4cm distal to its origin, as demonstrated by color duplex ultrasound. Transverse
image (left) depicting the renal vein (V.R) and superior mesenteric artery (A.M.S) anterior to the aorta (A). Color duplex fails to demonstrate ow
in the occluded superior mesenteric artery (3.3mm). More anteriorly, the splenic vein (V.L) is seen; the renal vein (V.R), including its termination
in the vena cava (V.C), is depicted longitudinally (ow coded in blue), to the left of the aorta sectioned obliquely. Anteriorly, the portal vein (V.P)
is shown with blue-coded ow. Between the renal and portal veins, the cross section of the red gastroduodenal artery is seen at its junction with
the pancreaticoduodenal artery. It is depicted beneath the lower margin of the portal vein and marked (A↑G). In transverse orientation, this collateral pathway can be followed in its entire length including relling of the superior mesenteric artery. The longitudinal image (right) depicts the
superior mesenteric artery (A.MES.S) anterior to the obliquely sectioned aorta (red). Color signals are absent from the superior mesenteric artery
segment in the left half of the image (XX), where it is merely seen as a hypoechoic, tubular structure. Along its course to the right of the image, it
is relled by the pancreaticoduodenal artery from posterolaterally (displayed in red, toward transducer). There is short backward ow in the unoccluded segment.
b The Doppler waveform shows rather high ow in the postocclusive segment of the superior mesenteric artery (ow toward the periphery coded
in blue in the color duplex image) with a postprandial peak systolic velocity (PSV) of 120cm/s and an end-diastolic velocity (EDV) of 30cm/s, suggesting good collateral ow through the gastropancreaticoduodenal artery (coded red in the color image). Proximal to the entry of this collateral,
the occluded segment of the superior mesenteric artery is depicted as a hypoechoic, tubular structure. Around the site of entry of the collateral,
ow is highly turbulent. The postocclusive waveform shows a slightly delayed systolic rise, reduced pulsatility, and a larger end-diastolic component.
c Angiogram: Occlusion of the superior mesenteric artery at its origin (arrow) with relling through the gastroduodenal and pancreaticoduodenal
arteries. There is interference from the superimposed aorta at the lower margin. As a result of delayed contrast medium passage through the collateral pathways, the contrast medium has already disappeared from the aorta at the level of the celiac trunk and origin of the superior mesenteric
artery by the time the relled superior mesenteric artery becomes opacied
6
. Fig. 6.59 (Atlas) Inammatory bowel disease.
Acute abdomen with wall thickening of bowel loops on B-mode ultrasonography. The demonstration of ow in the bowel wall in the color
duplex mode dierentiates inammatory thickening of the wall from
thickening due to acute ischemia or mesenteric vein thrombosis, which
exhibits the characteristic bull’s eye sign. The inammatory origin is
also underlined by the large diastolic ow component in the Doppler
waveform
Chapter 6 · Visceral andRetroperitoneal Vessels
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. Fig. 6.60a–c (Atlas) Hepatic artery aneurysm.
a A structure of mixed echogenicity measuring 6×5cm and showing ow signals in the color duplex mode is depicted in the portal hilum. Stagnation thrombus (TH) is seen in the posterior portion of the aneurysm. For the surgical procedure, it is important to precisely locate the vessels
6
entering and arising from the aneurysm (AN), in particular the gastroduodenal artery, which is shown to arise from the anteroinferior aspect of the
aneurysm (blue, left section). The middle section depicts the elongated proper hepatic artery (A.HEP) curving around the aneurysm. The right section shows the common hepatic artery (A.HEP) emptying into the aneurysm and arising from the celiac trunk (T.C) on the right side of the image.
As the hepatic artery aneurysm also involves the gastroduodenal artery, reconstruction of the hepatic artery is necessary after resection of the
aneurysm. If the aneurysm were localized proximal to the gastroduodenal artery, the latter would ensure arterial supply of the liver.
b Upper abdominal CT scan showing subhepatic mass (arrowhead): hepatic artery aneurysm with partial thrombosis (arrowhead).
c Angiogram depicting hepatic artery aneurysm (center)
. Fig. 6.61 (Atlas) Splenic artery aneurysm.
The B-mode image shows an anechoic cystic lesion in the omental bursa (leftmost). The diagnosis of an aneurysm is suggested by the color coding in the duplex mode (left center). The junction of the aneurysm with the vessel is seen upon rotation of the transducer; in this example the
splenic artery (A.L) shortly after its origin from the celiac trunk (T.C; A = aorta, A.H = hepatic artery). Moving the transducer laterally to the left
(right center), the distal splenic artery (A.L, with sample volume) can be traced along its course from the aneurysm (AN A.L) to the splenic hilum.
The vascular relationships of the aneurysm are thus determined sonographically prior to surgery. The Doppler waveform (rightmost) shows the
typical low-resistance ow of the splenic artery
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a
c de
. Fig. 6.62a–e (Atlas) Course of the renal arteries.
a Adequate diagnostic evaluation for renal artery stenosis (RAS) is crucially dependent on the meticulous visualization of the course of the renal
artery. The transverse upper abdominal view on the left shows the right renal artery (A.REN.RE) following an arched course after arising from the
aorta (proximal segment with ow in red toward transducer and distal segment with ow in blue away from transducer) below the vena cava
(V.C). Anteriorly, the superior mesenteric artery (red, A.M.S) and portal vein (blue, V.P) are seen. A Pourcelot index of 0.6 is calculated for the origin
of the renal artery from a peak systolic velocity (PSV) of 74.7cm/s and an end-diastolic velocity (EDV ) of 29.7cm/s.
b Renal artery at the renal hilum imaged from the ank (in transverse orientation) with the beam striking the vessel at an adequate angle. The
waveform and the Pourcelot index are the same at the hilum as at the origin, suggesting that no hemodynamically signicant stenosis is present
along the course of the renal artery between these two sampling sites.
c Since 25% of all kidneys are supplied by a paired renal artery and hypertension may be caused by stenosis at the origin of the second branch,
the examiner must always look for a second renal artery branch by moving the transducer posteriorly in transverse orientation. Here, a second
renal artery coded in blue arises from the aorta 1cm from the origin of the rst one. The characteristic renal artery waveform conrms the identity
of the second artery. In longitudinal orientation (rightmost image), the renal arteries can be identied posterior to the vena cava with blood ow
in the renal arteries and in the vena cava depicted in blue. Three renal artery branches with blood ow coded in blue are seen below the vena
cava; this is due to early division of the inferior branch of the paired renal artery on this side.
d Diagram illustrating the diculties in placing the angle correction cursor parallel to the direction of ow in a tortuous or curved renal artery
segment, which is not uncommon at the origin of the right renal artery (RRA). These pitfalls must be borne in mind to ensure correct grading of
atherosclerotic RAS, which tends to occur at the origin (see . Fig. 1.23b).
e Angiogram: Two renal arteries arise from the aorta on the right with early division of the inferior branch
b
5˚
RRA
65˚
RRA
A
A
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. Fig. 6.63a, b (Atlas) Sonoanatomy of the renal arteries.
a The left renal artery usually has a length of 5–6cm, from the aorta to the renal hilum. Scattering by bowel gas makes it dicult to scan the entire
length of the left artery in a single plane. The left image depicts the renal artery with ow in red (toward transducer) at its origin and in blue at the
renal hilum (away from transducer). The change in the color coding does not indicate an actual change in ow direction but only a change relative
to the transducer. The right image depicts the left renal vein (ow in red, toward transducer) anterior to the artery along its course to the vena
cava anterior to the aorta.
b The image shows the right renal artery undercrossing the vena cava. Its proximal and middle thirds are depicted with ow coded in blue (A.R).
The vena cava (V.C, blue) is seen anterior to it and the aorta is sectioned transversely (A, red) at the right margin of the image. Anteriorly, the superior mesenteric artery (A.M.S) and vein (V.M.S) are seen. Between the aorta and the superior mesenteric artery, there is a short stretch of the left
renal vein (V.R.L, blue). The distal third of the right renal artery is coded in red (ow toward transducer) at the renal hilum (NIERE RE). The Doppler
waveform was obtained from the middle third (posterior to the vena cava), the preferred site of stenosis in bromuscular dysplasia
. Fig. 6.64a–c (Atlas) Horseshoe kidney.
a Horseshoe kidneys have atypical arteries and veins. Besides additional lower pole vessels, a fth renal artery supplying the renal bridge crossing
over the aorta may be present as in the example shown. The young woman had an infected renal cyst (Z) in the preaortic bridge of the horseshoe
kidney. Pus was drained from the cyst under ultrasound guidance. In inconclusive cases, the Doppler waveform can help to establish the identity
of a vessel. Here, the inferior of the two vessels, coursing over the cyst (Z) and renal parenchyma, has the typical waveform of a renal artery and is
thus identied as a supernumerary fth renal artery (A.R).
b The artery coursing more superiorly (A.M.S) does not show the low-resistance ow typical of renal arteries but a mixed type characteristic of
mesenteric arteries.
c Closer inspection of the vascular supply (transverse image on the right, longitudinal image on the left) shows the right lower polar artery (A.R)
with ow in blue. This artery follows an atypical course, anterior to the vena cava on its way to the lower pole, after arising from the aorta (AO). A
retroaortic renal vein with ow coded in blue (V.R) passes from the left lower pole into the vena cava (V.C). There is aliasing in the renal artery due
to the low pulse repetition frequency used to detect slow venous (and arterial) ow. The longitudinal image on the left again shows the fth renal
artery (A.R) coursing to the renal parenchyma in front of the aorta (AO) after drainage of the infected cyst (site indicated by the X in the kidney)
6.3 · Atlas: Visceral andRetroperitoneal Vessels
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. Fig. 6.65a, b (Atlas) Pelvic kidney.
If a kidney cannot be identied in its usual location in the ank, this should prompt a search for a pelvic kidney. The arterial supply of an ectopic
pelvic kidney is highly variable with one or more renal arteries arising from the aorta or from the iliac artery. Also, the examiner must bear in mind
that two polar arteries may be present and that stenosis in either of them can be the cause of hypertension. In the example, two polar arteries
arising from the common iliac artery are identied; the two origins can be dierentiated by moving and slightly rotating the transducer (lower
pole artery in a and upper pole artery in b); stenosis in either artery is ruled out as ow velocity is below 120cm/s. In patients with an ectopic
kidney and aberrant arterial supply, renal hypertension can be caused by proximal common iliac artery stenosis
6
. Fig. 6.66a–d (Atlas) Renal artery stenosis– PTA.
a Doppler waveform obtained in the presence of moderate to severe stenosis at the origin of the renal artery with marked turbulence and a peak
systolic velocity (PSV) of 310cm/s and end-diastolic velocity (EDV) of 100cm/s.
b Doppler waveform from the same renal artery as in a after percutaneous transluminal angioplasty (PTA) shows return to normal ow velocity
(PSV of 80cm/s).
c X-ray densitometry (same patient as in a, before PTA): Measurement demonstrates a stenosis at the origin of the left renal artery with an area
reduction of 86.3%.
d X-ray densitometry (same patient as before, after PTA; corresponding Doppler waveform in b): Residual stenosis with a 31.3% area reduction,
which is hemodynamically nonsignicant. There is spectral broadening in the corresponding Doppler waveform but no accelerated ow
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. Fig. 6.67a–h (Atlas) Renal artery stenosis– indirect criteria.
The waveform from the renal hilum on the left yields a peak systolic velocity (PSV) of 85.7cm/s and an end-diastolic velocity (EDV) of 47.2cm/s,
from which a resistance index (RI; Pourcelot index) of 0.64 is calculated.
b The corresponding values in the right renal artery are: PSV of 125cm/s, EDV of 58.1cm/s, and a resulting RI of 0.75. The 10% RI dierence is consistent with the diagnosis of renal artery stenosis (RAS) and indicates postocclusive ow in the artery with the lower RI.
High-grade renal artery stenosis– PTA.
c Patient with two left renal arteries and a PSV of 275cm/s in the upper pole artery, consistent with high-grade RAS caused by atherosclerotic
plaque (P) at the origin of the artery. There is aliasing in the renal artery (A.R.L); the red ow signals anteriorly indicate the left renal vein (ow
toward transducer).
d The Doppler waveform from the origin of the left renal artery conrms high-grade stenosis with a PSV over 4m/s with the color ow image
showing pronounced perivascular vibration (audible bruit on auscultation).
e Subsequent angiography with PTA conrms high-grade stenosis of both polar arteries on the left.
f Flank pain after PTA prompted a duplex ultrasound examination. In the lower pole of the kidney, both arterial and venous ow signals are
obtained from the hilum to the periphery. The upper portion shows rareed perfusion in the pole (capsular vessels) and no arterial ow at the
hilum, consistent with occlusion of the upper pole artery after PTA.
g Angiogram conrms occlusion of the upper pole artery and normal ow in the lower pole artery.
Renal artery stenosis in diabetes mellitus– indication for PTA?
h High-grade stenosis of the left renal artery (A.R.L) with a PSV of 293cm/s and an EDV of 21cm/s, from which an RI of 0.9 is calculated. An RI of
>0.8 indicates parenchymal damage and xed hypertension, so that PTA is no longer a promising option. Stenotic plaque at the origin of the renal
artery from the aorta (A) causes acoustic shadowing (SS). Retroaortic course of the left renal vein (V.R.L)
6.3 · Atlas: Visceral andRetroperitoneal Vessels
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. Fig. 6.68a–c (Atlas) Renal artery stenosis in diabetes mellitus– indirect criteria.
a In a patient with a long history of insulin-dependent diabetes mellitus and macro- and microangiopathy, the Doppler waveform obtained at
the origin of the right renal artery shows turbulence and accelerated ow indicative of renal artery stenosis (RAS). Duplex imaging provides no
adequate information for estimating the degree of stenosis due to plaque with acoustic shadowing at the origin. In interpreting the peak systolic
velocity (PSV) of just over 2m/s somewhat distal to the stenosis, one has to take into account possible hypertensive episodes during spectral Doppler sampling as well as the known higher pulsatility of blood ow with higher PSV in diabetics. In the case presented, for instance, the resistive
index (Pourcelot index) is calculated from the Doppler spectra of both distal (hilar) renal artery segments for conrmation of the hemodynamic
signicance of the stenosis.
b The waveform from the right hilum yields a PSV of 80.7cm/s and an end-diastolic velocity (EDV) of 19.8cm/s with a Pourcelot index of 0.75. The
gray-scale image depicts the liver (L) above the kidney.
c The waveform from the left hilum shows more pulsatile ow with a PSV of 71.1cm/s and an EDV of 5.8cm/s; the Pourcelot index is 0.91. Compared with the ndings on the left side, the waveform of the right renal artery appears to be unusually normal, which is due to the fact that the
eects of diabetes and stenosis cancel each other. The waveform from the left, which is too pulsatile for a renal artery, is attributable to medial
sclerosis in long-standing diabetes mellitus and renal parenchymal damage. The much lower Pourcelot index of the right renal artery (over 10% in
side-to-side comparison) is abnormal and indicates a hemodynamically signicant proximal stenosis. This interpretation relies on the assumption
that other factors explaining the dierence such as asymmetric parenchymal kidney damage can be ruled out
6
. Fig. 6.69 (Atlas) Suprarenal aortic aneurysm with renal artery
stenosis.
Sonographic evaluation of the renal artery is indicated to evaluate the
relationship of its origin to an aortic aneurysm. The transverse upper
abdominal view shows the right renal artery arising from an aortic
aneurysm with partial thrombosis and a diameter of 4.5cm at the level
of the renal artery origin (hypoechoic, concentric thrombus also at the
renal artery origin). In addition, there is high-grade renal artery stenosis with a peak systolic velocity (PSV) exceeding 5m/s
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. Fig. 6.70a, b (Atlas) Vessel compression by tumor.
a A leiomyosarcoma (conrmed by ultrasound-guided core biopsy) splays the vena cava (V.C) and aorta in the retroperitoneum. A long segment
of the renal artery (A.REN.RE) running through the tumor is moderately constricted (Doppler-derived PSV of 250cm/s). The vessels are located by
color duplex imaging to avoid inadvertent vascular damage by subsequent ultrasound-guided core biopsy. Anteriorly, the portal vein (V.P) is also
compressed by the tumor.
b The superior mesenteric artery encased by the tumor (sarcoma) at its root is also constricted along an extended segment (PSV of 450cm/s)
. Fig. 6.71a, b (Atlas) Transplant kidney.
a Color duplex image depicting the artery of the transplant kidney, anastomosed to the iliac artery, with ow coded in blue (ow away from
transducer), while the iliac artery is shown with ow in red (toward transducer). The Doppler waveform has a large diastolic component and the
typical pattern of low-resistance ow indicating a functioning graft without rejection.
b Diagram of the connections of the renal transplant vessels to the iliac vessels