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1SS
Pictorial
Essay
Differential Diagnosis of Head and Neck Lesions Based on Their Space of Origin. 2. The lnfrahyoid Portion of the Neck Wendy
R. K. Smoker1’2
and
H. Ric
Harnsberger1
The infrahyoid portion of the neck can be considered as a series of contiguous fascial planes and intervening spaces that lend themselves well to axial imaging. These spaces can serve as a basis on which to formulate differential diagnoses for diseases in this region. This pictorial essay describes the fascia and fascial spaces of the infrahyoid portion of the neck. The contents of each space, the common abnormalities affecting the space, and the characteristic displacements produced by disease in each space are reviewed.
skull base to the upper mediastinum, forming the anterior wall of the retropharyngeal space and contributing to formation of the carotid sheath. The deep layer of the deep cervical fascia encircles the paraspinous and prevertebral muscles and associated struc-
Anatomy
The two major fascial layers of the infrahyoid superficial
and
deep cervical perficial,
deep
cervical
fasciae.
fascia comprises
middle,
and deep
layers,
deep
surrounding
cervical
cervical
fascia,
and scapulae. contributes
fascia
the skull
to the superficial
is the superficial space. Extending from the hyoid
[1].
the superficial
to the skin
layer
to the clavicles
of muscles
sheath
(Fig.
anteriorly,
and
1 ). The
layer of deep cervical
bone
of
and superficial
base
a number
of the carotid
the su-
the infrahyoid
of fascial spaces
It splits to enclose
to formation
space external
from
important
layers,
and cleaves
the neck,
lies deep
extending
neck are the
more
three distinct
portion of the neck into a number Completely
The
fascia
the middle
layer
of the deep cervical fascia envelops the anterior infrahyoid strap muscles and merges with the superficial layer. A portion ofthe
middle
layer splits to enclose
space (Fig. 2). Posteriorly,
Received October 1 5, 1 990; accepted 1 Department of Radiology, University 2
Present address:
Department
the contents
ofthe
the middle layer extends
visceral
from the
Fig. 1.-Axial line diagram illustrates superficial layer of deep cervical fascia (bold lines). This fascia splits to enclose stemocleldomastoid and
trapezius
platysma, sternocleidomastoid, and external jugular veins. m
after revision January 4, 1991. of Utah, 50 North Medical Dr., Salt Lake City,
of Radiology.
July 1991 0361-803X/9i/157i-0i55
=
inferior
omohyoid,
muscle,
v
=
© American
Roentgen
and trapezius
muscles
vein.
UT 84132.
Medical College of Virginia, Box 61 5, MCV Station, Richmond, VA 23298. Address
Smoker. AJR 157:155-159,
muscles, forms a sling around inferior belly of omohyoid muscle
(anchoring it to clavicle), and contributes to formation of carotid sheath. Extemaljugular veins lie external to, or embedded within, this fascial layer. Superficial space, external to deepest fibers of superficial layer, contains
Ray Society
reprint requests
to W. A. K.
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1S6
SMOKER
2.-Axial
Fig.
fascia (bold lines). with superficiallayer
AND
line diagram illustrates middle layer of deep cervical This layer envelops anterior strap muscles and fuses anteriorly.
Main portion
of middle
layer forms
a fascial
HARNSBERGER
AJR:157,
Fig. 4.-Axial line diagram shows spaces of infrahyoid Note how anterior and posterior cervical spaces (stippled other deep spaces of neck.
July 1991
portion of neck. area) lie among
sheath around contents of visceral space (vs). A capsule for thyroid gland is formed
by a splitting
of middle
layer.
Posteriorly,
middle
layer
forms
anterior wall of retropharyngeal space, contributes to formation of carotid sheath, and merges with superficial layer covering deep surface of sternocleidomastoid muscle. n = nerve.
Fig. 5.-Midsagittal
Fig. 3.-Axial line diagram illustrates deep layer of deep cervical fascia lines). Anterior aspect of deep layer splits into alar (anterior) and prevertebral (posterior) portions, forming danger space. Alar portion (arrowheads) forms lateral and posterior walls of retropharyngeal space and contributes to formation of carotid sheath. (Anterior wall of retropharyngeal space is formed by middle layer of deep cervical fascia [dotted llne]). (bold
Attaching to transverse processes, the major prevertebral vides prevertebral space into anterior prevertebral space
posterior paraspinal nerve, a = artery, v
portion of prevertebral
space (P). m
portion
infrahyold is caused
cervical pharyngeal via danger
walls of the retropharyngeal
=
muscle,
n
=
space
and contributing
to carotid
sheath formation, extends from the skull base to the diaphragm. The more posterior prevertebral portion extends
(Figs.
base to the coccyx.
splitting 4 and 5) [i
layers
and spaces
of
space space,
may transgress below termination
thin alar fascia and continue of retropharyngeal space.
inferiorly
Spaces
of the
The
carotid
Infrahyoid
Portion
of the
Neck
vein.
=
space. Anteriorly the deep layer splits into two portions. The more anterior alar portion, forming the posterior and lateral
the skull
fascial
subdi-
tures (Fig. 3). Attaching to the transverse processes, the deep layer subdivides the prevertebral space into the prevertebral space proper and the paraspinal portion of the prevertebral
anterior
shows
proper (A) and
sheaths,
from
line diagram
portion of neck. Note that termination of retropharyngeal space by fusion of middle layer and alar portion of deep layer of deep fascia in upper thoracic region. However, infections within retro-
The space
created
of the deep layer is called the danger ,
2].
by the
space
spaces
composed
are
of all three
circumscribed layers
of deep
by the
carotid
cervical
fascia.
The carotid spaces contain the internaljugular veins, common or internal carotid arteries, and vagus nerves. The sympathetic
plexus
is embedded
in the medial
sheath
walls.
Numer-
ous lymph nodes of the deep cervical chain are also enmeshed within the sheaths. Typical displacements of surrounding structures produced by a carotid space mass are illustrated in Figure 6. Diseases common to the carotid space include carotid body paragangliomas (Fig. 7), neurogenic tumors, internal jugular vein thrombophlebitis (Fig. 8), vascular pseudotumors (asymmetric internal jugular vein, ectatic carotid artery), and isolated nodal disease (inflammatory or neoplas-
tic).
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Fig. 6.-Mass in carotid space. Axial diagram illustrates typical displacements surrounding spaces (arrowheads).
Fig. 9.-Mass
line of
in visceral space. Axial line characteristic displacements of surrounding spaces (arrowheads).
diagram
depicts
LESIONS
i 57
Fig. 7.-Paraganglioma in carotid space. Axial MR image, 750/25 (TRITE), reveals normal flow voids that localize normal right carotid space vessels (dots). Splaying of proximal left internal and external carotid arteries (straight arrows) plus compression and posterior displacement of left internal jugular vein (curved arrow) localizes lesion to left carotid space.
Fig. 8.-Thrombosis and thrombophlebitis of jugular vein in carotid space. Axial Ti-weighted MR image, 1000/20 (TR/TE), enhanced with gadopentetate dimeglumine shows thrombosis of right internal jugular vein (dot) and marked inflammatory changes in right carotid space. Right sternocleidomastoid muscle (M) and anterior strap muscles (m) are enlarged. Right anterior cervical and retropharyngeal spaces (arrowheads) also are enhanced. c = common carotid artery.
SITES
AJR:157, July 1991
OF
INFRAHYOID
Fig. 10.-Colloid cyst in visceral space. Enhanced CT scan shows large cyst involving left lobe of thyroid; displacement of other visceral space structures to right, across midline; and lateral displacement of ca-
rotid space vessels bilaterally (dots), left greater than right. Although right lobe of thyroid gland (T) is well visualized, left lobe is represented by thin rim of enhancing tissue (arrowheads) around cyst.
The visceral space is delimited by the middle layer of deep cervical fascia (Fig. 2). The visceral space contains the thyroid and parathyroid glands, trachea, esophagus, paraesophageal nodes, and recurrent laryngeal nerves. A diagram of the typical displacements of surrounding spaces produced by a visceral space mass is presented in Figure 9. Thyroid gland disease (cysts [Fig. 1 0], carcinomas, adenomas, multinodular goiters) predominates in this space, with parathyroid and esophageal disease being much less common. As most thyroglossal duct cysts are embedded in the anterior strap
muscles
cervical visceral
(which
Fig.
1
i.-Thyroglossal
space. Enhanced
duct
cyst
CT scan localizes
in visceral
lesion to
superficial aspect of visceral space by showing that, in addition to lying deep to platysma muscle (arrows), lesion also lies deep to, and is embedded within, anterior strap muscles. A faint fat plane is visible between cyst and displaced strap muscles (arrowheads).
are enclosed
by the
middle
fascia), they are also considered space (Fig. 1 1).
layer
of deep
to lie within
the
Although separately defined fascial spaces, the retrophaand danger spaces are considered together, because, within the infrahyoid portion of the neck, disease affecting ryngeal
these spaces
cannot
be differentiated
radiologically.
From a
clinical standpoint, the danger space is important because, terminating at the level of the diaphragm, it represents a pathway by which retropharyngeal space infections may con-
18
SMOKER
AND
HARNSBERGER
AJA:157,
12.-Mass
Fig.
Axial
line
in retropharyngeal shows characteristic
diagram
placements
of
July 1991
surrounding
space. dis(arrow-
spaces
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heads).
Fig. 13.-Abscess in retropharyngeal space. Enhanced CT scan shows visceral space and prevertebral space proper widely separated by
abscess.
Longus
pressed
posteriorly
colli muscles (c) are comand vessels in carotid spaces are displaced bilaterally (dots). This Icsion
cannot
be localized
to retropharyngeal
vs
danger spaces on the basis of CT scan.
13
12
Fig. 14.-Mass in prevertebral space. Axial line diagram illustrates typical displacements of
surrounding spaces produced by a lesion involving both prevertebral space proper and paraspinal portion of prevertebral space (arrowheads). Fig. 15.-Abscess hanced
CT scan
in prevertebral shows
abscess
space. Eninvolving
pre-
vertebral
space proper after interbody cervical fusion. Abnormality can be compartmentalized by observing abnormal enhancement and enlargement of longus colli muscles bilaterally (dots). (Bone windows [not shown] also revealed vertebral body destruction.) Although perceived separation between visceral space and vertebral body might suggest mass in retropharyngeal space, is not characteristic
configuration for disease
of this lesion of retropharyn-
geal space, and longus colli muscles are not compressed posteriorly, as was seen in Fig. 13.
14
15 Fig. 16.-Mass in anterior cervical space. Axial line diagram depicts typical surrounding fascial space displacements (arrowheads).
Fig. i7.-Lipoma in anterior cervical space. Enhanced CT scan shows marked compression and displacement of left stemocleidomastoid muscle (s), posteromedial displacement of carotid space vessels (dots), and slight compression of left lobe of thyroid gland (T).
16
17
tinue inferiorly in the posterior mediastinum (Fig. 5) [3]. These spaces contain only fat in the infrahyoid portion of the neck,
paraspinal, and scalene muscles; vertebral artery and vein; vertebral body; and spinal cord. A line diagram of the char-
and disease
acteristic displacements of surrounding a lesion involving both the prevertebral
in them presents
tie appearance involved
a somewhat
(Fig. 12) [4]. These
by infection
(Fig.
characteristic
spaces
1 3), hematoma,
are most extranodal
bow-
often met-
astatic disease, lipomas, or edema associated with internal jugular vein thrombosis or lymphatic obstruction [4]. The prevertebral space is delimited by the deep layer of deep cervical fascia (Fig. 3). It contains the prevertebral,
spaces produced by space proper and the
paraspinal portion of the prevertebral space is presented Figure 14. The prevertebral space proper can be involved infection (osteomyelitis/diskitis) domeningoceles associated
and a variety
with
of pseudotumors
in by
(Fig. 15), chordomas, pseubrachial plexus avulsions,
(anterior
herniated
disks,
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AJR:157,July
SITES
1991
Fig. 18.-Mass in posterior cervical space. Axial line diagram illustrates characteristic displacements of surrounding spaces (arrowheads).
OF
INFRAHYOID
1S9
LESIONS
Fig. 19.-Malignant node in posterior cervical space. Axial Ti-weighted MR image, 600/20(TR/TE), enhanced with gadopentetate dimeglumine, reveals nodal disease of the spinal accessory chain of the left posterior cer-
vical space in a patient
with Hodgkin
lymphoma.
Note
marked deformity of external neck contour (arrows), flattening of muscles in paraspinal portion of prevertebral space (arrowheads), anterior displacement of sternocleidomastoid muscle (dots), and anteromedial displacement of left carotid artery (A).
Fig. 20.-Multispatial tularemia. Enhanced CT scan shows a large suppurative node in external aspect of superficial space (N) with thickening and enhancement of overlying skin (white arrows) and underlying platysma muscle (black arrow). Suppurative
adenopathy is also present bilaterally in deep cervical chain nodes of carotid spaces (arrowheads),
ing nodes nodes
vertebral
osteophytes,
longus
colli tendon
calcification).
The
paraspinal portion of the prevertebral space can be involved by a variety of primary bone tumors (osteoblastoma, chordoma, aneurysmal bone cysts) and by the pseudotumor ap-
pearance nying
of levator
injury
scapulae
to the spinal
muscle
accessory
hypertrophy nerve.
accompa-
Lymphomas,
met-
and smaller,
are present
of posterior
reactive-appear-
in spinal
cervical
accessory
spaces
(dots).
Although often isolated to a single space, disease of the infrahyoid part of the neck may involve many spaces simultaneously. This is especially common with nodal disease involving the major node-bearing spaces (deep cervical chain of the carotid space and spinal accessory chain of the pos-
tenor cervical
space).
Discrete
involvement
of these
nodes
astatic disease, and neurogenic tumors may involve either compartment. The anterior and posterior cervical spaces are situated among the other spaces of the infrahyoid portion of the neck,
presents a pattern of multispatial disease and is most often seen with lymphoma, infection (Fig. 20), and nodal metastatic
with complex deep cervical
the characteristic displacements of surrounding spaces produced by disease isolated to each space, and the common abnormalities affecting each space allows an organized approach to the evaluation of infrahyoid neck disease.
fascial fascia
filled, these spaces
boundaries involving all three layers of (Fig. 5). Because they are primarily fat
typically
provide
symmetric
imaging
land-
marks on axial imaging. Isolated disease of the anterior cervical space produces characteristic displacements of sur-
rounding
disease (especially Knowledge
squamous
of the fascial
cell carcinoma
planes
and spaces,
metastases). their contents,
fascial spaces (Fig. 16) and is limited to lipomas (Fig.
1 7) and more inferiorly located Disease isolated to the posterior
second branchial cleft cysts. cervical space is much more
common and easily localized by displacement of surrounding fascial spaces (Fig. 1 8). Cystic hygromas/lymphangiomas, lipomas, liposarcomas, and third branchial cleft cysts occur within this space. Because it contains the spinal accessory
lymph node chain, the posterior monly affected by both disease (Fig. 19).
cervical
inflammatory
space and
is also com-
malignant
nodal
REFERENCES 1 . Grodinsky
M, Holyoke
EA. The fasciae
and fascial
spaces
of the head,
neck and adjacent regions. Am J Anat 1938;63:367-408 2. Stiemberg CM. Deep-neck space infections: diagnosis and management. Arch Otolaryngol Head Neck Surg 1986;1 12:1274-1279 3. Levit GW. Cervical fascia and deep neck infections. Laryngoscope
1970;80:409-435 4. Davis
WL, Harnsberger
evaluation of the normal i990;1 74:59-64
HA, Smoker and diseased
WAK,
Watanabe
retropharyngeal
AS. The radiologic space.
Radiology
1SS
Pictorial
Essay
Differential Diagnosis of Head and Neck Lesions Based on Their Space of Origin. 2. The lnfrahyoid Portion of the Neck Wendy
R. K. Smoker1’2
and
H. Ric
Harnsberger1
The infrahyoid portion of the neck can be considered as a series of contiguous fascial planes and intervening spaces that lend themselves well to axial imaging. These spaces can serve as a basis on which to formulate differential diagnoses for diseases in this region. This pictorial essay describes the fascia and fascial spaces of the infrahyoid portion of the neck. The contents of each space, the common abnormalities affecting the space, and the characteristic displacements produced by disease in each space are reviewed.
skull base to the upper mediastinum, forming the anterior wall of the retropharyngeal space and contributing to formation of the carotid sheath. The deep layer of the deep cervical fascia encircles the paraspinous and prevertebral muscles and associated struc-
Anatomy
The two major fascial layers of the infrahyoid superficial
and
deep cervical perficial,
deep
cervical
fasciae.
fascia comprises
middle,
and deep
layers,
deep
surrounding
cervical
cervical
fascia,
and scapulae. contributes
fascia
the skull
to the superficial
is the superficial space. Extending from the hyoid
[1].
the superficial
to the skin
layer
to the clavicles
of muscles
sheath
(Fig.
anteriorly,
and
1 ). The
layer of deep cervical
bone
of
and superficial
base
a number
of the carotid
the su-
the infrahyoid
of fascial spaces
It splits to enclose
to formation
space external
from
important
layers,
and cleaves
the neck,
lies deep
extending
neck are the
more
three distinct
portion of the neck into a number Completely
The
fascia
the middle
layer
of the deep cervical fascia envelops the anterior infrahyoid strap muscles and merges with the superficial layer. A portion ofthe
middle
layer splits to enclose
space (Fig. 2). Posteriorly,
Received October 1 5, 1 990; accepted 1 Department of Radiology, University 2
Present address:
Department
the contents
ofthe
the middle layer extends
visceral
from the
Fig. 1.-Axial line diagram illustrates superficial layer of deep cervical fascia (bold lines). This fascia splits to enclose stemocleldomastoid and
trapezius
platysma, sternocleidomastoid, and external jugular veins. m
after revision January 4, 1991. of Utah, 50 North Medical Dr., Salt Lake City,
of Radiology.
July 1991 0361-803X/9i/157i-0i55
=
inferior
omohyoid,
muscle,
v
=
© American
Roentgen
and trapezius
muscles
vein.
UT 84132.
Medical College of Virginia, Box 61 5, MCV Station, Richmond, VA 23298. Address
Smoker. AJR 157:155-159,
muscles, forms a sling around inferior belly of omohyoid muscle
(anchoring it to clavicle), and contributes to formation of carotid sheath. Extemaljugular veins lie external to, or embedded within, this fascial layer. Superficial space, external to deepest fibers of superficial layer, contains
Ray Society
reprint requests
to W. A. K.
Downloaded from www.ajronline.org by 218.75.135.177 on 10/06/15 from IP address 218.75.135.177. Copyright ARRS. For personal use only; all rights reserved
1S6
SMOKER
2.-Axial
Fig.
fascia (bold lines). with superficiallayer
AND
line diagram illustrates middle layer of deep cervical This layer envelops anterior strap muscles and fuses anteriorly.
Main portion
of middle
layer forms
a fascial
HARNSBERGER
AJR:157,
Fig. 4.-Axial line diagram shows spaces of infrahyoid Note how anterior and posterior cervical spaces (stippled other deep spaces of neck.
July 1991
portion of neck. area) lie among
sheath around contents of visceral space (vs). A capsule for thyroid gland is formed
by a splitting
of middle
layer.
Posteriorly,
middle
layer
forms
anterior wall of retropharyngeal space, contributes to formation of carotid sheath, and merges with superficial layer covering deep surface of sternocleidomastoid muscle. n = nerve.
Fig. 5.-Midsagittal
Fig. 3.-Axial line diagram illustrates deep layer of deep cervical fascia lines). Anterior aspect of deep layer splits into alar (anterior) and prevertebral (posterior) portions, forming danger space. Alar portion (arrowheads) forms lateral and posterior walls of retropharyngeal space and contributes to formation of carotid sheath. (Anterior wall of retropharyngeal space is formed by middle layer of deep cervical fascia [dotted llne]). (bold
Attaching to transverse processes, the major prevertebral vides prevertebral space into anterior prevertebral space
posterior paraspinal nerve, a = artery, v
portion of prevertebral
space (P). m
portion
infrahyold is caused
cervical pharyngeal via danger
walls of the retropharyngeal
=
muscle,
n
=
space
and contributing
to carotid
sheath formation, extends from the skull base to the diaphragm. The more posterior prevertebral portion extends
(Figs.
base to the coccyx.
splitting 4 and 5) [i
layers
and spaces
of
space space,
may transgress below termination
thin alar fascia and continue of retropharyngeal space.
inferiorly
Spaces
of the
The
carotid
Infrahyoid
Portion
of the
Neck
vein.
=
space. Anteriorly the deep layer splits into two portions. The more anterior alar portion, forming the posterior and lateral
the skull
fascial
subdi-
tures (Fig. 3). Attaching to the transverse processes, the deep layer subdivides the prevertebral space into the prevertebral space proper and the paraspinal portion of the prevertebral
anterior
shows
proper (A) and
sheaths,
from
line diagram
portion of neck. Note that termination of retropharyngeal space by fusion of middle layer and alar portion of deep layer of deep fascia in upper thoracic region. However, infections within retro-
The space
created
of the deep layer is called the danger ,
2].
by the
space
spaces
composed
are
of all three
circumscribed layers
of deep
by the
carotid
cervical
fascia.
The carotid spaces contain the internaljugular veins, common or internal carotid arteries, and vagus nerves. The sympathetic
plexus
is embedded
in the medial
sheath
walls.
Numer-
ous lymph nodes of the deep cervical chain are also enmeshed within the sheaths. Typical displacements of surrounding structures produced by a carotid space mass are illustrated in Figure 6. Diseases common to the carotid space include carotid body paragangliomas (Fig. 7), neurogenic tumors, internal jugular vein thrombophlebitis (Fig. 8), vascular pseudotumors (asymmetric internal jugular vein, ectatic carotid artery), and isolated nodal disease (inflammatory or neoplas-
tic).
Downloaded from www.ajronline.org by 218.75.135.177 on 10/06/15 from IP address 218.75.135.177. Copyright ARRS. For personal use only; all rights reserved
Fig. 6.-Mass in carotid space. Axial diagram illustrates typical displacements surrounding spaces (arrowheads).
Fig. 9.-Mass
line of
in visceral space. Axial line characteristic displacements of surrounding spaces (arrowheads).
diagram
depicts
LESIONS
i 57
Fig. 7.-Paraganglioma in carotid space. Axial MR image, 750/25 (TRITE), reveals normal flow voids that localize normal right carotid space vessels (dots). Splaying of proximal left internal and external carotid arteries (straight arrows) plus compression and posterior displacement of left internal jugular vein (curved arrow) localizes lesion to left carotid space.
Fig. 8.-Thrombosis and thrombophlebitis of jugular vein in carotid space. Axial Ti-weighted MR image, 1000/20 (TR/TE), enhanced with gadopentetate dimeglumine shows thrombosis of right internal jugular vein (dot) and marked inflammatory changes in right carotid space. Right sternocleidomastoid muscle (M) and anterior strap muscles (m) are enlarged. Right anterior cervical and retropharyngeal spaces (arrowheads) also are enhanced. c = common carotid artery.
SITES
AJR:157, July 1991
OF
INFRAHYOID
Fig. 10.-Colloid cyst in visceral space. Enhanced CT scan shows large cyst involving left lobe of thyroid; displacement of other visceral space structures to right, across midline; and lateral displacement of ca-
rotid space vessels bilaterally (dots), left greater than right. Although right lobe of thyroid gland (T) is well visualized, left lobe is represented by thin rim of enhancing tissue (arrowheads) around cyst.
The visceral space is delimited by the middle layer of deep cervical fascia (Fig. 2). The visceral space contains the thyroid and parathyroid glands, trachea, esophagus, paraesophageal nodes, and recurrent laryngeal nerves. A diagram of the typical displacements of surrounding spaces produced by a visceral space mass is presented in Figure 9. Thyroid gland disease (cysts [Fig. 1 0], carcinomas, adenomas, multinodular goiters) predominates in this space, with parathyroid and esophageal disease being much less common. As most thyroglossal duct cysts are embedded in the anterior strap
muscles
cervical visceral
(which
Fig.
1
i.-Thyroglossal
space. Enhanced
duct
cyst
CT scan localizes
in visceral
lesion to
superficial aspect of visceral space by showing that, in addition to lying deep to platysma muscle (arrows), lesion also lies deep to, and is embedded within, anterior strap muscles. A faint fat plane is visible between cyst and displaced strap muscles (arrowheads).
are enclosed
by the
middle
fascia), they are also considered space (Fig. 1 1).
layer
of deep
to lie within
the
Although separately defined fascial spaces, the retrophaand danger spaces are considered together, because, within the infrahyoid portion of the neck, disease affecting ryngeal
these spaces
cannot
be differentiated
radiologically.
From a
clinical standpoint, the danger space is important because, terminating at the level of the diaphragm, it represents a pathway by which retropharyngeal space infections may con-
18
SMOKER
AND
HARNSBERGER
AJA:157,
12.-Mass
Fig.
Axial
line
in retropharyngeal shows characteristic
diagram
placements
of
July 1991
surrounding
space. dis(arrow-
spaces
Downloaded from www.ajronline.org by 218.75.135.177 on 10/06/15 from IP address 218.75.135.177. Copyright ARRS. For personal use only; all rights reserved
heads).
Fig. 13.-Abscess in retropharyngeal space. Enhanced CT scan shows visceral space and prevertebral space proper widely separated by
abscess.
Longus
pressed
posteriorly
colli muscles (c) are comand vessels in carotid spaces are displaced bilaterally (dots). This Icsion
cannot
be localized
to retropharyngeal
vs
danger spaces on the basis of CT scan.
13
12
Fig. 14.-Mass in prevertebral space. Axial line diagram illustrates typical displacements of
surrounding spaces produced by a lesion involving both prevertebral space proper and paraspinal portion of prevertebral space (arrowheads). Fig. 15.-Abscess hanced
CT scan
in prevertebral shows
abscess
space. Eninvolving
pre-
vertebral
space proper after interbody cervical fusion. Abnormality can be compartmentalized by observing abnormal enhancement and enlargement of longus colli muscles bilaterally (dots). (Bone windows [not shown] also revealed vertebral body destruction.) Although perceived separation between visceral space and vertebral body might suggest mass in retropharyngeal space, is not characteristic
configuration for disease
of this lesion of retropharyn-
geal space, and longus colli muscles are not compressed posteriorly, as was seen in Fig. 13.
14
15 Fig. 16.-Mass in anterior cervical space. Axial line diagram depicts typical surrounding fascial space displacements (arrowheads).
Fig. i7.-Lipoma in anterior cervical space. Enhanced CT scan shows marked compression and displacement of left stemocleidomastoid muscle (s), posteromedial displacement of carotid space vessels (dots), and slight compression of left lobe of thyroid gland (T).
16
17
tinue inferiorly in the posterior mediastinum (Fig. 5) [3]. These spaces contain only fat in the infrahyoid portion of the neck,
paraspinal, and scalene muscles; vertebral artery and vein; vertebral body; and spinal cord. A line diagram of the char-
and disease
acteristic displacements of surrounding a lesion involving both the prevertebral
in them presents
tie appearance involved
a somewhat
(Fig. 12) [4]. These
by infection
(Fig.
characteristic
spaces
1 3), hematoma,
are most extranodal
bow-
often met-
astatic disease, lipomas, or edema associated with internal jugular vein thrombosis or lymphatic obstruction [4]. The prevertebral space is delimited by the deep layer of deep cervical fascia (Fig. 3). It contains the prevertebral,
spaces produced by space proper and the
paraspinal portion of the prevertebral space is presented Figure 14. The prevertebral space proper can be involved infection (osteomyelitis/diskitis) domeningoceles associated
and a variety
with
of pseudotumors
in by
(Fig. 15), chordomas, pseubrachial plexus avulsions,
(anterior
herniated
disks,
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AJR:157,July
SITES
1991
Fig. 18.-Mass in posterior cervical space. Axial line diagram illustrates characteristic displacements of surrounding spaces (arrowheads).
OF
INFRAHYOID
1S9
LESIONS
Fig. 19.-Malignant node in posterior cervical space. Axial Ti-weighted MR image, 600/20(TR/TE), enhanced with gadopentetate dimeglumine, reveals nodal disease of the spinal accessory chain of the left posterior cer-
vical space in a patient
with Hodgkin
lymphoma.
Note
marked deformity of external neck contour (arrows), flattening of muscles in paraspinal portion of prevertebral space (arrowheads), anterior displacement of sternocleidomastoid muscle (dots), and anteromedial displacement of left carotid artery (A).
Fig. 20.-Multispatial tularemia. Enhanced CT scan shows a large suppurative node in external aspect of superficial space (N) with thickening and enhancement of overlying skin (white arrows) and underlying platysma muscle (black arrow). Suppurative
adenopathy is also present bilaterally in deep cervical chain nodes of carotid spaces (arrowheads),
ing nodes nodes
vertebral
osteophytes,
longus
colli tendon
calcification).
The
paraspinal portion of the prevertebral space can be involved by a variety of primary bone tumors (osteoblastoma, chordoma, aneurysmal bone cysts) and by the pseudotumor ap-
pearance nying
of levator
injury
scapulae
to the spinal
muscle
accessory
hypertrophy nerve.
accompa-
Lymphomas,
met-
and smaller,
are present
of posterior
reactive-appear-
in spinal
cervical
accessory
spaces
(dots).
Although often isolated to a single space, disease of the infrahyoid part of the neck may involve many spaces simultaneously. This is especially common with nodal disease involving the major node-bearing spaces (deep cervical chain of the carotid space and spinal accessory chain of the pos-
tenor cervical
space).
Discrete
involvement
of these
nodes
astatic disease, and neurogenic tumors may involve either compartment. The anterior and posterior cervical spaces are situated among the other spaces of the infrahyoid portion of the neck,
presents a pattern of multispatial disease and is most often seen with lymphoma, infection (Fig. 20), and nodal metastatic
with complex deep cervical
the characteristic displacements of surrounding spaces produced by disease isolated to each space, and the common abnormalities affecting each space allows an organized approach to the evaluation of infrahyoid neck disease.
fascial fascia
filled, these spaces
boundaries involving all three layers of (Fig. 5). Because they are primarily fat
typically
provide
symmetric
imaging
land-
marks on axial imaging. Isolated disease of the anterior cervical space produces characteristic displacements of sur-
rounding
disease (especially Knowledge
squamous
of the fascial
cell carcinoma
planes
and spaces,
metastases). their contents,
fascial spaces (Fig. 16) and is limited to lipomas (Fig.
1 7) and more inferiorly located Disease isolated to the posterior
second branchial cleft cysts. cervical space is much more
common and easily localized by displacement of surrounding fascial spaces (Fig. 1 8). Cystic hygromas/lymphangiomas, lipomas, liposarcomas, and third branchial cleft cysts occur within this space. Because it contains the spinal accessory
lymph node chain, the posterior monly affected by both disease (Fig. 19).
cervical
inflammatory
space and
is also com-
malignant
nodal
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M, Holyoke
EA. The fasciae
and fascial
spaces
of the head,
neck and adjacent regions. Am J Anat 1938;63:367-408 2. Stiemberg CM. Deep-neck space infections: diagnosis and management. Arch Otolaryngol Head Neck Surg 1986;1 12:1274-1279 3. Levit GW. Cervical fascia and deep neck infections. Laryngoscope
1970;80:409-435 4. Davis
WL, Harnsberger
evaluation of the normal i990;1 74:59-64
HA, Smoker and diseased
WAK,
Watanabe
retropharyngeal
AS. The radiologic space.
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