Download MRI Atlas of the Abdomen

MRI Atlas of the Abdomen
(a self-guided tutorial)
Jeff Velez HMS3
Eric Chiang, MD
Gillian Lieberman, MD
Goals
The purpose of this atlas is to provide students with;
• an outline of the anatomy of the abdomen via MR imaging.
• an introduction to how an MR image is created.
• a basic understanding of how the manipulation of various
•
parameters (TR,TE, pulse sequence) of an MR scan yield
desired tissue differentiation.
a list of some basic sequences used in abdominal MR.
By coupling this review of how an MR image is created and
manipulated with a thorough tour of abdominal anatomy seen
through MRI, this tutorial can serve as an instructive tool in
preparing students for their likely future clinical encounters with
abdominal MRI in evaluating and managing abdominal disease.
2
Introduction
Magnetic resonance (MR) imaging has been in widespread clinical use for
well over a decade. Its use was primarily localized to the evaluation of the
central nervous system and then more recently, the musculoskeletal system.
Motion during the cardiac cycle , respiration, and peristalsis made MR
imaging of the thorax and abdomen a major challenge. MR imaging of the
abdomen started with the evaluation of solid visceral organs such as the
liver and kidney. With technologic developments in MR hardware and
software occurring at a swift and steady pace, MR imaging of the abdomen
is beginning to expand beyond the solid viscera into the entire abdomen,
including the hollow viscus of the GI tract.
3
Basics of MRI
• In order to read and understand an MR image, one must gain a basic understanding
•
•
of the principles underlying its production.
MR imaging is based on the naturally occurring magnetic moment that exists within
the nuclei of a hydrogen atom, as well as its ubiquitous presence in organic tissue.
When an external magnetic field is applied to organic tissue, protons within hydrogen
nuclei align themselves in parallel with this field and also begin to resonate. When a
radiofrequency (RF) pulse is applied to these aligned protons, it provides enough
energy to dislodge (or excite) them from this orientation. However, this is a
temporary phenomenon, and the nuclei relax back into realignment with the external
magnetic field. Upon relaxation, energy is released in the form of RF waves. This
“echo” is detected and a signal of variable intensity for a given location is produced.
Tissue contrast is created because different tissues have different relaxation times.
This is attributable to the different microenvironments surrounding the magnetized
nuclei.
4
4 Key Parameters of MRI
• T1
• T2
• Echo Time (TE)
• Repetition Time (TR)
• The relaxation times of protons shifting from a higher to
•
lower energy level, are referred to as T1 and T2 and are
tissue specific.
The TE and TR are variables that can be controlled by an
MR scanner operator.
5
T1 and T2
• T1 and T2 represent relaxation time constants.
• Each tissue has a specific, inherent T1 and T2 value.
• For example: fat has a short T1 and T2, whereas fluid has a long T1 and
•
•
•
T2.
These values are measured in milliseconds.
T1 – the time it takes nuclei in a particular tissue that has been excited or
“dislodged” from its parallel orientation to return to its nonexcited state.
(The time when about 63% of the original longitudinal magnetization is
reached).
T2 – the time it takes nuclei in a particular tissue that has been excited into
a (phase coherent) transverse or perpendicular orientation to return to its
non excited (non phase coherent) state. (The time when transverse
magnitization decreases to 37% of the original value).
6
TR and TE
• These are two major parameters that can be adjusted (unlike T1 and T2) to
•
•
create the desired tissue differentiation.
When an MR image is taken, it begins with a magnetic field being
established that is parallel with the bore of the scanner. This field has a
strength on the order of 1-2 Teslas, depending on the scanner. Once this is
established, and protons have aligned with the field, a sequence of
radiofrequency (RF) pulses are administered. This excites the protons to a
higher energy level. This is then followed by relaxation back into a low
energy state. This relaxation time is constant (T1 and T2). What can be
changed however is the repetition time (TR) or time between administered
RF pulses. What also can be manipulated is the time that the RF “echo” is
received by the RF detector. This time is referred to as TE, or echo time.
By adjusting TE and TR, according to a tissue’s T1 and T2, the various
tissues in a region of interest can be differentiated.
7
T1 weighted images vs. T2
weighted images
• The following 2 slides offer graphs to help explain tissue contrast on
T1 vs. T2 weighted images.
• These graphs are depictions of the signal intensity as function of
time for two tissues types (fat and fluid) in an external magnetic
field.
• A helpful way to analyze these graphs is to identify which curve
provides the higher signal intensity (red or blue) at the time point
indicated by the dashed vertical line (detection time). That point
represents the tissue that will appear brighter on the MR image.
• Keep in mind that the TR and TE (along with the sequence of RF
pulses) are what we can manipulate, while T1 and T2 are constant
and tissue dependent. They are represented by the degree of line
curvature (exponential relationship) on the graphs to follow.
8
T1 Weighted Image
T1 Weighted Image—short TR and TE
Signal Intensity
— fat
— fluid
TR = repetition time
TE = echo time
TR
In this graph
fat has a
greater signal
intensity than
fluid. Tissues
with short T1
and T2 (fat)
will appear
brighter than
those with
longer T1 and
T2 (fluid).
TE
Although this is a gross oversimplification, when an image is T1 weighted, this means that the protocol used to
scan a patient involves adjusting the TE and TR (shortening their times) in a manner that will cause tissues
with fast T1 and T2 relaxation times (e.g. fat) to appear brighter.
9
T2 Weighted Image
T2 Weighted Image—long TR and TE
Signal Intensity
— fat
— fluid
TR = repetition time
TE = echo time
TR
In this graph
fluid has a
greater signal
intensity than
fat. Tissues
with long T1
and T2 (fluid)
will appear
brighter than
those with
short T1 and
T2 (fat).
TE
•On a T2 weighted image the protocol used is one that will
result in tissue with long T1 and T2 (fluid) having a higher signal
intensity. This is illustrated in the following slides.
•This protocol involves using a TR and TE that are relatively
longer than the T1 weighted sequence.
10
Beyond T1 and T2—Abdominal MRI
• Along with the advancements in MR scanner hardware technology,
developments in the pulse sequences used have led to the growing
role of MRI in abdominal imaging.
• The fundamental principle behind these sequences is to maximize
contrast, resolution, speed, and coverage while keeping motion and
noise (relative to signal) at a minimum.
• A list of commonly used sequences (acronyms provided) that
capture abdominal anatomy and pathology include: VIBE, HASTE,
STIR, TSE, and GRE sequences.
• Although a description of all of these sequences is beyond the scope
of this atlas, a brief discussion of the VIBE sequence can provide an
introduction to the MR parameters that are manipulated to achieve
maximal contrast, resolution, speed, and coverage.
11
Volumetric Interpolated Breath-hold Examination
(VIBE)
• The VIBE Sequence is T1 based (short TR and TE).
• It is a complex 3D Fourier transform sequence that allows for fast
acquisition time, thus reducing motion artifact and allowing for
adequate coverage of the abdomen.
• In a given amount of time the VIBE sequence can provide better
tissue contrast by utilizing a technique known as fat saturation.
• Given the relatively high resolution and coverage, VIBE sequences
can be reconstructed and used for angiographic examinations.
• The axial, coronal, sagittal, and selected 3D reconstructions of the
abdomen to follow were performed using the VIBE sequence.
12
Anatomy of the Abdomen
Throughout this atlas, in axial, coronal, sagittal, and oblique 3D planes, we will
highlight;
•
•
•
•
•
•
•
•
Liver
Biliary System
Pancreas
Spleen
Gastrointestinal Tract
Kidneys
Retroperitoneum
Peritoneum
13
We have used images from 3
different patients:
• Patient A - 32 year old female
•
•
MR settings: VIBE sequence, MR abdomen
Planes: Axial, coronal, and sagittal; coronal MRCP image
Patient B - 54 year old female
MR settings: VIBE sequence, MRA abdomen (focused on celiac/SMA)
Planes: Maximum intensity projection (MIP) 3D reconstruction
Patient C - 27 year old male
MR Settings: VIBE sequence, MRA abdomen (focused on renal arteries)
Planes: Maximum intensity projection 3D reconstruction
14
Pt A - Axial VIBE
Plate 1
15
Pt A - Axial VIBE
Plate 2
16
Pt A - Axial VIBE - Dome of the Liver
Liver
R. Ventricle
L. Ventricle
Inferior
Vena Cava
Esophagus
Aorta
L. Lower
lobe of
lung
R. Lower
lobe of
lung
Azygos v.
Plate 3
17
Pt A - Axial VIBE
Plate 4
18
Pt A - Axial VIBE
Plate 5
19
Pt A - Axial VIBE
Plate 6
20
Pt A - Axial VIBE
Plate 7
21
Pt A - Axial VIBE
Plate 8
22
Pt A - Axial VIBE - Hepatic Veins
L. Lobe of liver
(lateral segment)
Gastric fundus
L. hepatic v.
L. Lobe of liver
(medial segment)
M. hepatic v.
Inferior vena
cava
R. lobe of liver
(anterior segment)
R. hepatic v.
Aorta
R. lobe of liver
(posterior segment)
Plate 8
Azygos v.
Gastroesophageal junction
Hemiazygos v.
L. lower lobe of lung
Spleen
23
Pt A - Axial VIBE
Plate 9
24
Pt A - Axial VIBE
Plate 10
25
Pt A - Axial VIBE - Hepatic Divisions
LMS
LLS
L. hepatic vein
M. hepatic vein
RAS
Inferior vena
cava
R. hepatic vein
LLS—Lateral segment of left lobe
RPS
LMS—Medial segment of left lobe
RAS—Anterior segment of right lobe
RPS—Posterior segment of right lobe
Plate 10
The superior aspect of the liver serves as a good reference point when
inspecting axial images of the liver. It can be divided into 4 segments
based on the alignment of the hepatic veins draining into the inferior vena
cava. The dashed line indicates the respective course of the three hepatic
veins. These segments can be further divided into superior and inferior
segments.
26
Pt A - Axial VIBE
Plate 11
27
Pt A - Axial VIBE
Plate 12
28
Pt A - Axial VIBE - Splenic Hilum
The spleen is an
intraperitoneal structure,
enclosed by peritoneum
except at its hilum where the
splenic vessels enter and
leave. It can be readily
differentiated from the kidney
by its location adjacent to the
posterolateral chest wall.
Splenic flexure
Posterior aspect of
stomach
Tail of pancreas
Splenic vein
Splenic artery
Posterior chest wall
Important relationships of the
spleen include abutment of
the posterior aspect of the
stomach as well as the tail of
the pancreas
Plate 12
29
Pt A - Axial VIBE
Plate 13
30
Pt A - Axial VIBE
Plate 14
31
Pt A - Axial VIBE - Adrenal Gland and Spleen
Gastric fundus
L. portal vein
Inferior vena cava
Aorta
R. portal vein
R. adrenal gland
Body of pancreas
L. adrenal gland
Spleen
R. crus of diaphragm
L. crus of
diaphragm
Vertebral body
Ascending
lumbar veins
Spinal cord
Ascending
lumbar veins
Plate 14
32
Pt A - Axial VIBE
Plate 15
33
Pt A - Axial VIBE - Adrenal Glands
This image illustrates the
characteristic “inverted Y”
appearance of the
adrenal glands. The
adrenal glands reside on
the anteromedial and
superior aspect of the
kidneys.
Plate 15
34
Pt A - Axial VIBE
Plate 16
35
Pt A - Axial VIBE
Plate 17
36
Pt A - Axial VIBE - Celiac Trunk
Common hepatic a.
Ligamentum teres
Celiac Trunk
Gastric body
Hepatic a. fossa
Splenic flexure
Caudate lobe
Body of Pancreas
Portal vein
L. adrenal gland
Desc. colon
Spleen
Inferior vena cava
L. kidney
R. kidney
Aorta
Plate 17
37
Pt A - Axial VIBE
Plate 18
38
Pt A - Axial VIBE
Hepatic artery
Portal vein
Caudate lobe
Inferior vena cava
R. Adrenal gland
(see plates 20-24)
Plate 18
A notable anatomic relationship exists at the level of the right
adrenal gland that involves a posterior to anterior sequence of
structures that line up in a relatively linear fashion. These
include, from posterior to anterior—R. adrenal gland, IVC,
caudate lobe, portal vein, and hepatic artery.
39
Pt A - Axial VIBE
Plate 19
40
Pt A - Axial VIBE - Body of Pancreas
Gastric body
Small bowel
Splenic vein
Pancreatic duct
L. lobe (lateral)
Ligamentum teres
L. lobe (medial)
Neck of gallbladder
Porta hepatis
Portal vein
Hepatic artery
Inferior vena cava
R. kidney
Superior mesenteric artery
Plate 19
Aorta
Body of pancreas
L. kidney
Descending colon
Spleen
41
Pt A - Axial VIBE
Plate 20
42
Pt A - Axial VIBE
Plate 21
43
Pt A - Axial VIBE - Origin of SMA
Gastric body
Small bowel
Descending colon
Ligamentum teres
Body of pancreas
Gastric antrum
Hepatic artery
Neck of gallbladder
Porto-splenic
confluence
Portal vein
Neck of pancreas
Splenic vein
R. kidney
Plate 21
Inferior vena cava
R. renal vein
Superior mesenteric artery
Aorta
L. kidney
44
Pt A - Axial VIBE
Plate 22
45
Pt A - Axial VIBE - Relationships of the Superior
Mesenteric Artery
Body of pancreas
This slide shows another
important relationship that
exists surrounding the SMA.
There are four structure to be
aware of. These include the
body of the pancreas and
splenic artery, which pass over
the SMA anteriorly. Posteriorly,
the duodenum and left renal
vein cross behind the SMA. In
this particular image, the
transverse aspect of the
duodenum is out of plane
leaving a small distal portion
visible.
Plate 22
Splenic vein
Superior mesenteric
artery (SMA)
Distal duodenum
L. Renal vein
Aorta
46
Pt A - Axial VIBE
Plate 23
47
Pt A - Axial VIBE
Plate 24
48
Pt A - Axial VIBE - Origin of the Renal Arteries
Falciform ligament
Ligamentum teres fissure
Gastric antrum
Gastric body
Superior mesenteric vein
Hepatic flexure
Superior mesenteric artery
Small bowel
L. renal vein
L. renal artery
Body of gallbladder
Duodenum (1st part)
Head of pancreas
Duodenum (2nd part)
Hilum of left kidney
Hilum of right kidney
Inferior vena cava
Plate 24
49
Pt A - Axial VIBE
Plate 25
50
Pt A - Axial VIBE - Clinical Relationships of the
GallBladder
Gallbladder
Hepatic flexure
An important clinical relationship
exists between the gallbladder and
the GI tract. In this image the
hepatic flexure lies adjacent and
medial to the body of the gallbladder.
As the gallbladder ascends its neck
abuts the superior and/or descending
duodenum (which in this image lies
medial to the flexure, see plate 59).
In gallstone ileus, a stone from the
gallbladder tracks through the wall of
the gallbladder and enters the
duodenum causing obstruction at the
narrow lumen of the ileocecal valve.
If the stone forms a fistula with the
hepatic flexure, and enters the colon,
ileus is unlikely due to the wide
colonic lumen.
Duodenum
(descending)
Plate 25
51
Pt A - Axial VIBE
Plate 26
52
Pt A - Axial VIBE
Plate 27
53
Pt A - Axial VIBE - Renal Hilum
Duodenum (3nd part)
Ligamentum teres fissure
Head of pancreas
Body of gallbladder
Superior mesenteric vein
Hepatic flexure
Transverse colon
Duodenum (2st part)
Superior mesenteric artery
Small bowel
L. renal vein
R. renal pelvis
Hepatorenal recess
(Morrison’s pouch)
Hilum of left kidney
Inferior vena cava
Renal pelvis fat
Deep back muscles
Hilum of right kidney
Quadratus lumborum
Psoas muscle
Plate 27
54
Pt A - Axial VIBE
Plate 28
55
Pt A - Axial VIBE
Plate 29
56
Pt A - Axial VIBE - Kidney and Retroperitoneum
The kidneys are retroperitoneal structures
that reside at the level of T12 to L3, with
the right typically being lower than the left
due to the presence of the liver. It is
encapsulated and housed, along with the
adrenal glands, within the perirenal space.
This space is surrounded by Gerota’s
fascia. The anterior and posterior
pararenal space surround Gerota’s fascia
with an additional layer of adipose tissue
(see slide 74 for a more detailed look at
the retroperitoneum).
These retroperitoneal locations have
clinical relevance when staging for renal
cell carcinoma or assessing for renal
infection or trauma.
Anterior
pararenal space
In terms of relations, the kidney is well
connected, coming into contact (through
peri- and pararenal spaces) bilaterally with
the adrenals and diaphragm superiorly and
the quadratus lumborum and psoas
muscles inferomedially. On the right side
the kidney is adjacent to the liver,
duodenum, and ascending colon. On the
left side the kidney is in contact with
spleen, stomach, pancreas, jejunum, and
descending colon.
Kidney
Perirenal space
Perirenal space
Posterior
pararenal space
Plate 29
57
Pt A - Axial VIBE
Plate 30
58
Pt A - Axial VIBE - Hepatic Flexure
Superior mesenteric
artery
Superior mesenteric
vein
Aorta
Transverse colon
Duodenum
Small bowel
Anterior pararenal
space*
Flank stripe*
Perirenal space*
Posterior pararenal
space*
Fundus of gallbladder
Hepatic flexure
Inferior vena cava
Lumbar vessels
Quadratus lumborum
Deep back muscles
Ureter
Psoas muscle
Plate 30
*
Marked structures of retroperitoneum will be discussed in the following slide.
59
A Simplified Overview of the
Retroperitoneal Spaces
Gastric body
Liver
Pancreas
Anterior
Pararenal
space
Flank stripe
Perirenal
space
Right kidney
Inferior
vena cava
Spleen
Transversalis
fascia
Gerota’s
fascia
Left kidney
Posterior
Pararenal
space
60
Pt A - Axial VIBE
Plate 31
61
Pt A - Axial VIBE
Plate 32
62
Pt A - Axial VIBE
Plate 33
63
Pt A - Axial VIBE - Lower Poles of Kidneys
Transverse colon
Aorta
Fundus of gall bladder
Small bowel
Inferior vena cava
L. ureter
Liver
R. ureter
Psoas muscle
Quadratus lumborum
Erector spinae
Plate 33
64
Pt A - Axial VIBE
Plate 34
65
Pt A - Axial VIBE
Plate 35
66
Pt A - Axial VIBE
Plate 36
67
Pt A - Axial VIBE
Plate 37
68
Pt A - Axial VIBE
Plate 38
69
Pt A - Axial VIBE
Plate 39
70
Pt A - Axial VIBE
Plate 40
71
Pt A - Coronal Plane - VIBE Reformatted
Plate 41
72
Pt A - Coronal Plane - VIBE Reformatted
Plate 42
73
Pt A - Coronal Plane - VIBE Reformatted
Gallbladder
R. ventricle
Diaphragm
Falciform
ligament
Liver
Ligamentum teres
Gallbladder
Hepatic flexure
Gastric body
Transverse colon
Small bowel
Plate 42
74
Pt A - Coronal Plane - VIBE Reformatted
Plate 43
75
Pt A - Coronal Plane - VIBE Reformatted
Plate 44
76
Pt A - Coronal Plane - VIBE Reformatted
Transverse Colon
L. ventricle
Diaphragm
R. ventricle
Gastric fundus
L. lobe of liver
Portal vein
R. lobe of liver
Gastric body
Fundus of gallbladder
Hepatic flexure
Transverse colon
Small bowel
Splenic flexure
Gastric antrum
Plate 44
77
Pt A - Coronal Plane - VIBE Reformatted
Plate 45
78
Pt A - Coronal Plane - VIBE Reformatted
Plate 46
79
Pt A - Coronal Plane - VIBE Reformatted
Pancreas and Splenic and Superior Mesenteric Vein
The pancreas
can be
subdivided into
five segments.
They include a
head, neck,
uncinate
process, body
and tail.
In this image,
the body and
neck of the
pancreas are
located centrally,
anterior to the
splenic vein (out
of plane).
Neck of
pancreas
Body of
pancreas
Superior
mesenteric
vein
The pancreas is a
retroperitoneal
structure that has
many close
anatomic relations.
One such relation
occurs posterior to
the neck of the
pancreas, and
involves the union
of the splenic vein
and superior
mesenteric vein
(SMV) to form the
portal vein. This
image is in the
plane of the
pancreas and the
more anteriorly
situated SMV.
Plate 46
80
Pt A - Coronal Plane - VIBE Reformatted
Plate 47
81
Pt A - Coronal Plane - VIBE Reformatted
Union of Splenic and Superior Mesenteric Veins
L. ventricle
Diaphragm
R. ventricle
Gastric body/fundus
Splenic flexure
Body of pancreas
Portal vein
R. and L.
hepatic
arteries
Neck of
pancreas
Gallbladder
Duodenum
(descending)
Hepatic flexure
Plate 47
Ascending colon
Head of pancreas
Superior mesenteric v.
Splenic v.
Superior mesenteric a.
Abdominal aorta
Small bowel
82
Pt A - Coronal Plane - VIBE Reformatted
Plate 48
83
Pt A - Coronal Plane - VIBE Reformatted
Branching of the Celiac artery
R. ventricle
Ligamentum teres
L. ventricle
L. gastric artery
Hepatic artery
Portal vein
Celiac artery
Hepatic flexure
Aorta
Inferior vena cava
Gastric body/fundus
Body of pancreas
Small bowel
Splenic v.
Superior mesenteric
artery
Plate 48
84
Pt A - Coronal Plane - VIBE Reformatted
Plate 49
85
Pt A - Coronal Plane - VIBE Reformatted
Portal Vein
R. atrium
Inferior vena cava
Right hepatic vein
L. ventricle
Gastric fundus
Celiac artery
Portal vein
Superior mesenteric a.
Abdominal aorta
Hepatic flexure
Spleen
Body of pancreas
Splenic v.
Small bowel
Inferior vena cava
L. renal vein
Plate 49
86
Pt A - Coronal Plane - VIBE Reformatted
Plate 50
87
Pt A - Coronal Plane - VIBE Reformatted
Course of the Inferior Vena Cava (IVC)
Ascending from the confluence of the
common iliac veins the IVC travels
parallel and a few centimeters to the
right of the vertebral column. The
IVC crosses anterior to the right renal
artery, receiving the right and left
renal vein. The left renal vein crosses
over the aorta anterior and parallel to
the left renal artery.
Along with also receiving gonadal,
suprarenal, and lumbar veins along
this course, the IVC next passes along
the inferior visceral border of the liver
where it receives input from the three
hepatic veins.
Following this the IVC passes through
the vena caval foramen to then enter
the right atrium.
Right
atrium
IVC
Right renal
artery
IVC
This image illustrates the IVC passing
the right renal artery anteriorly, the
liver posteriorly, and entering the right
atrium of the heart.
Plate 50
88
Pt A - Coronal Plane - VIBE Reformatted
Plate 51
89
Pt A - Coronal Plane - VIBE Reformatted
Esophagogastric Junction
Spleen
R. atrium
Esophagus
Gastric cardia
Body of pancreas
Superior
branch of
portal vein
Inferior
branch of
portal vein
Plate 51
Celiac artery
Splenic v.
Aorta
Hepatic flexure
Inferior vena cava
L. renal arteries
Psoas muscles
Small bowel
90
Pt A - Coronal Plane - VIBE Reformatted
Plate 52
91
Pt A - Coronal Plane - VIBE Reformatted
Plate 53
92
Pt A - Coronal Plane - VIBE Reformatted
Adrenal Glands
Thoracic aorta
Hepatic vein
Gastric cardia
Inferior vena cava
Abdominal aorta
R. adrenal gland
Right renal arteries
R. kidney
Hepatorenal recess
Spleen
Splenic v.
L. adrenal gland
L. kidney
L. renal arteries
Psoas m.
Plate 53
93
Pt A - Coronal Plane - VIBE Reformatted
Plate 54
94
Pt A - Coronal Plane - VIBE Reformatted
Plate 55
95
Pt A - Coronal Plane - VIBE Reformatted
Plate 56
96
Pt A - Coronal Plane - VIBE Reformatted
Renal Hilum and T12 Vertebral Body
Thoracic aorta
R. lower lobe of lung
Serratus anterior m.
Hepatic vein
Renal sinus fat
R. kidney
Hepatorenal recess
R. psoas m.
L. lower lobe of
lung
Hemiazygos v
Spleen
Splenic hilum
L. renal calyx
L. renal pelvis
L. kidney
L. psoas m.
Plate 56
97
Pt A - Coronal Plane - VIBE Reformatted
Plate 57
98
Pt A - Coronal Plane - VIBE Reformatted
Splenic Hilum
Thoracic aorta
R. lower lobe of lung
L. lower lobe of
lung
Serratus anterior m.
Splenic hilum
Spleen
Right lobe of liver
(posterior segment)
R. kidney
Splenic artery
L. kidney
Hepatorenal
recess
Renal calyx
R. psoas m.
L. psoas m.
Spinal canal
Plate 57
99
Pt A - Coronal Plane - VIBE Reformatted
Plate 58
100
Pt A - Coronal Plane - VIBE Reformatted
Plate 59
101
Pt A - Coronal Plane - VIBE Reformatted
Plate 60
102
Pt A - Coronal Plane - VIBE Reformatted
Spinal Canal at T10/Posterior Kidneys
L. lower lobe of
lung
R. lower lobe of lung
Right lobe of liver
(posterior segment)
Hepatorenal recess
Spinal canal
Spleen
Perirenal fat
L. kidney
Erector spinae m.
R. kidney
Spinal cord
Plate 60
103
Pt A - Sagittal Plane - VIBE Reformatted
Plate 61
104
Pt A - Sagittal Plane - VIBE Reformatted
Plate 62
105
Pt A - Sagittal Plane - VIBE Reformatted
Plate 63
106
Pt A - Sagittal Plane - VIBE Reformatted
Right Lobe of Liver
R. lung
Intercostal m.
Liver (vertical
span)
Posterior ribs
Anterior ribs
Subcutaneous fat
Plate 63
107
Pt A - Sagittal Plane - VIBE Reformatted
Plate 64
108
Pt A - Sagittal Plane - VIBE Reformatted
Plate 65
109
Pt A - Sagittal Plane - VIBE Reformatted
Gallbladder
Hepatic veins
R. lobe of liver
(anterior segment)
Branch of portal vein
R. lobe of liver
(posterior segment)
Hepatorenal recess
R. kidney
Posterior pararenal fat
Perirenal fat
Ascending colon
Gallbladder
Transverse colon
Plate 65
110
Pt A - Sagittal Plane - VIBE Reformatted
Plate 66
111
Pt A - Sagittal Plane - VIBE Reformatted
Hepatorenal Recess
Superior
30
The peritoneal recess between
the liver and kidney occupies an
important clinical location in the
abdomen. In the supine
position this recess, also known
as “Morrison’s pouch”, is the
lowest point where fluid (e.g
ascites) can collect.
Anterior
Anterior
Superior
Hepatorenal
Recess
Plate 66
112
Pt A - Sagittal Plane - VIBE Reformatted
Plate 67
113
Pt A - Sagittal Plane - VIBE Reformatted
Medulla of Right Kidney
R. Lobe of liver
(anterior segment)
Hepatic veins
R. Lobe of liver
(posterior segment)
Pararenal fat
Portal vein
Renal calyx
R. kidney (cortex)
Body of gallbladder
R. Kidney (medulla)
Hepatic flexure
Plate 67
114
Pt A - Sagittal Plane - VIBE Reformatted
Plate 68
115
Pt A - Sagittal Plane - VIBE Reformatted
Porta hepatis
Common bile duct
Portal vein
Hepatic artery
Plate 68
The porta hepatis is the “port” of entrance and exit to and
from the liver for the portal triad—portal vein, hepatic
artery, and common bile duct. This sagittal MR image
provides a cross section of the portal triad.
116
Pt A - Sagittal Plane - VIBE Reformatted
Plate 69
117
Pt A - Sagittal Plane - VIBE Reformatted
Inferior Vena Cava
Hepatic artery
R. lumbar vessels
Portal vein
Inferior vena cava
Psoas m.
Plate 69
118
Pt A - Sagittal Plane - VIBE Reformatted
Plate 70
119
Pt A - Sagittal Plane - VIBE Reformatted
Plate 71
120
Pt A - Sagittal Plane - VIBE Reformatted
Superior Mesenteric Vein
Thoracic aorta
Inferior vena cava
Liver
Abdominal aorta
Hepatic artery
Head of pancreas
Hepatic flexure
Superior mesenteric vein
Spinal canal
Duodenum
Uncinate process
Plate 71
121
Pt A - Sagittal Plane - VIBE Reformatted
Plate 72
122
Pt A - Sagittal Plane - VIBE Reformatted
Aorta, Celiac Artery, and Superior Mesenteric Artery
Aorta
Esophagogastric junction
Hepatic artery
Left lobe of liver
Celiac artery
Neck of pancreas
Duodenum (superior)
Splenic vein
Transverse colon
Plate 72
L. renal vein
Ascending colon
Superior mesenteric artery
Duodenum (transverse)
123
Pt A - Sagittal Plane - VIBE Reformatted
Plate 73
124
Pt A - Sagittal Plane - VIBE Reformatted
Plate 74
125
Pt A - Sagittal Plane - VIBE Reformatted
Plate 75
126
Pt A - Sagittal Plane - VIBE Reformatted
Medulla of Left Kidney
Gastric fundus
Left lobe of liver
(lateral segment)
Gastric body
Spleen
Pancreatic body and tail
Left kidney (medulla)
Renal calyx
Transverse colon
Perirenal fat
Small bowel
Left kidney (cortex)
Plate 75
127
Pt A - Sagittal Plane - VIBE Reformatted
Plate 76
128
Pt A - Sagittal Plane - VIBE Reformatted
Lesser Sac
The lesser sac is a blind pouch of peritoneum that is
bordered antero-superiorly by the posterior wall of the
stomach and the lesser omentum and postero-inferiorly
by the peritoneum overlying the body of the pancreas.
Gastric
fundus
Body and
tail of
pancreas
Gastric
body
In this image, the lesser sac can be seen on end as a
thin hypointense area between the stomach and the
pancreas.
Plate 76
129
Pt A - Sagittal Plane - VIBE Reformatted
Plate 77
130
Pt A - Sagittal Plane - VIBE Reformatted
Spleen
Apex of heart
Splenic flexure
Splenic vein
Gastric body
Spleen
Small bowel
Left kidney
Plate 77
131
Pt B - MRA with contrast, maximum
intensity projection 3D reconstruction of
superior mesenteric and celiac arteries
Plate 78
132
Pt B - MRA with contrast, maximum
intensity projection 3D reconstruction of
superior mesenteric and celiac arteries
Aorta
Hepatic artery
Celiac trunk
Splenic artery
Gastroduodenal artery
R. renal artery
Superior mesenteric artery
Plate 78
133
Pt B - MRA with contrast, maximum
intensity projection 3D reconstruction of
superior mesenteric and celiac arteries
Plate 79
134
Pt B - MRA with contrast, maximum
intensity projection 3D reconstruction of
superior mesenteric and celiac arteries
Aorta
Hepatic artery
Lumbar arteries
Splenic artery
R. renal artery
Celiac trunk
Superior mesenteric artery
L. renal artery
Plate 79
135
Pt B - MRA with contrast, maximum
intensity projection 3D reconstruction of
superior mesenteric and celiac arteries
Plate 80
136
Pt B - MRA with contrast, maximum
intensity projection 3D reconstruction of
superior mesenteric and celiac arteries
Plate 81
137
Pt B - MRA with contrast, maximum
intensity projection 3D reconstruction of
superior mesenteric and celiac arteries
Celiac trunk
Superior mesenteric artery
Inferior mesenteric artery
Plate 82
138
Pt B - MRA with contrast, maximum
intensity projection 3D reconstruction of
superior mesenteric and celiac arteries
Plate 83
139
Pt B - MRA with contrast, maximum
intensity projection 3D reconstruction of
superior mesenteric and celiac arteries
Left gastric artery
Hepatic artery
Celiac trunk
Splenic artery
Superior mesenteric artery
Lumbar arteries
Plate 83
140
Pt C - MRA with contrast, maximum
intensity projection 3D reconstruction of
renal arteries
Plate 84
141
Pt C - MRA with contrast, maximum
intensity projection 3D reconstruction of
renal arteries
Lumbar arteries
Right renal artery
Aorta
Left renal artery
L. ureter
Superior mesenteric
artery
Plate 84
142
Pt C - MRA with contrast, maximum
intensity projection 3D reconstruction of
renal arteries
Plate 85
143
Pt C - MRA with contrast, maximum
intensity projection 3D reconstruction of
renal arteries
Plate 86
144
Pt C - MRA with contrast, maximum
intensity projection 3D reconstruction of
renal arteries
Aorta
Superior mesenteric
artery
L. Ureter
Left renal artery
Right renal artery
Plate 86
145
Pt C - MRA with contrast, maximum
intensity projection 3D reconstruction of
renal arteries
Plate 87
146
Pt C - MRA with contrast, maximum
intensity projection 3D reconstruction of
renal arteries
Aorta
Superior
mesenteric
artery
Branches of L.
renal artery
L. Renal artery
Plate 87
147
Correlation of Axial, Coronal, and Sagittal MR Plate 1
Liver and Gastroesophageal junction
When examining the GI tract, a useful tool for
orientation is the stomach. If one follows axial slices in
the caudal direction from the diaphragm and GE junction
downward, an easy landmark of the stomach is its
characteristic longitudinally oriented rugae. These
provide an initial reference point from which one can
follow the GI tract distally through the duodenum to its
distal transverse and ascending segments.
148
Correlation of Axial, Coronal, and Sagittal MR Plate 2
Spleen
Given its
location
immediately
adjacent to the
posterior and
lateral ribs and
its lack of
surrounding
adipose tissue
(unlike the
kidneys), the
spleen is very
susceptible to
trauma. MR
imaging of the
abdomen can
serve as a
useful tool in
assessing
splenic trauma.
149
Correlation of Axial, Coronal, and Sagittal MR Plate 3
Celiac Trunk
The celiac artery arises off of the
aorta at the level of T12. It
trifurcates into the splenic, hepatic
and left gastric arteries. These
arteries supply the foregut of the
GI tract—distal esophagus,
stomach, duodenum, pancreas,
liver, gall bladder, and spleen.
150
Correlation of Axial, Coronal, and Sagittal Plate 4
Pancreas
Together these images capture the
body and tail of the pancreas. To
image the entire view of the pancreas
an oblique section can be helpful.
151
The Pancreas
This image
illustrates four
main segments of
the pancreas in
one plane.
These include the
tail, body, neck,
and head of the
pancreas.
Due to the fact
that the pancreas
typically slopes
inferiorly from the
tail at the splenic
hilum to its head
adjacent to the
duodenum, this
image was
reconstructed in
an oblique plane.
Head
Neck
Body
Tail
152
Correlation of Axial, Coronal, and Sagittal MR Plate 5
Gallbladder
Fluid is hypointense (dark) on these T1 weighted VIBE
images. The fluid-filled gallbladder illustrates this
appearance. To further examine the gallbladder and biliary
tree, T2 weighted MRCP (MR cholangiopancreatography) can
be used.
153
MRCP of the Biliary Tree
R. hepatic
duct
Cystic duct
Common bile
duct
Gallbladder
L. Hepatic
duct
Common
hepatic duct
Pancreatic
duct
154
Correlation of Axial, Coronal, and Sagittal MR Plate 6
Kidney (Right Upper Pole)
155
Correlation of Axial, Coronal, and Sagittal Plate 7
Kidney (Left Hilum)
156
Correlation of Axial, Coronal, and Sagittal MR Plate 8
Kidneys (Left Lower Pole) and Vertebral Musculature
Ureter
Vertebral
body
Psoas
muscle
Deep
back mm.
Quadratus
lumborum
Erector
spinae
The lower poles
of the kidneys lie
adjacent and
antero-lateral to
the muscles of
the back. These
include the
psoas, quadratus
lumboratum,
deep back
muscles, and
intermediate
(erector spinae)
back muscles.
Notice the small
hypointense
circular slice of
the left ureter
lying on the left
psoas muscle.
157
References
Christofordis, A Atlas of Axial, Sagittal, and Coronal Anatomy with CT
and MRI 1988
Novelline, RA Living Anatomy: A Working Atlas Using Computed
Tomography, Magnetic Resonance, and Angiography Images 1st
edition, 1987
Moore, K and Dalley, A Clinically Oriented Anatomy 4th edition, 1999
Fleckenstein, P Anatomy in Diagnostic Imaging 2nd edition, 2001
158
Special Thanks
Pamela Lepkowski, Education Coordinator at
Beth Israel Deaconess Medical Center for
technical assistance and editing.
159