대 한 방사선 의 학 회 지 1991; 27(2) : 199~205 Journal of Korean Radiological Society, March , 1991

Computed Tomography of Deep Neck Infections

Hyung Jin Kim, M.D. , Hae Gyeong Chung, M.D. , Jae Hyoung Kim, M.D. , Eui Gee Hwang, M.D.* , Sea Young Jeon* , M.D. , Sung Hoon Chung, M.D.

Department of Radiology, Col1ege of Medicine , Gyeongsang National University

- Abstract-

We retrospectively reviewed the CT of 11 patients with deep neck infections with a special emphasis on the loca­

tion and extent of the infection. the presence or absence of a drainable abscess. and , if any. associated complica­

tions. CT correctly denoted the location and extent of the space infection. even though the individuallayers of the

deep cervical fascia per se could not be identified. Infection was most frequent at the transhyoid neck (n = 7) and

confined to the suprahyoid and infrahyoid neck in 2 cases. respectively. There were common spaces involved ac­

cording to etiolo잉T. A1l 3 patients with dental infections of the lower third molar had involvement of the submylohyoid

space. In 1 patient with a fishbons injury to the month f1oor. the infection was found at the submylohyoid space

as well as sublingual space. CT clearly pointed out the presence of a drainable abscess in all surgically prov­

ed 10 patients , among whom the gas bubbles were seen in 5 patients. In addition. CT demonstrated the

significant complications of deep neck infection. and these were mediastinal involvement (n=2). airway en­

croachment (n=2) . jugular vein thrombosis (n=2). and reactive cervicallympnadenopathy (n=5) . We con­

clude that CT can be used as a principal diagnostic tool in the evaluation of deep neck infections.

Index Words: Face. infections 20.20

Neck , infections 27.20

Neck, computed tomography 27.1211

Deep neck infections are potentially life­

threatening conditions , but often result in dilemmas

in diagnosis and treatmen t. While computed

tomography (CT) has played a primary role in the

evaluation of neoplastic disorders of the neck. only

a few reports on CT of cervical infections have been

found in the literature (1-5). Needless to say. thorough

knowledge of the anatomy of the deep fascial layers

and spaces of the neck is essential in order to unders­

tand the pathways of spread and complications of cer­

vical infections. We report 11 cases of deep neck

infections evaluated by CT with a special emphasis on

their modes of spread and complications.

Materials and Methods

We retrospectively reviewed CT of 11 patients with

*경상대학교 의과대학 이비인후과학교실

deep neck infections from MarcI1. 1989 to September.

1990 , and compared it with the surgical and/or

medical findings. Patients only with infected cysts or

neoplasms or reactive cervical adenitis were exclud­

ed. There were eight men and three women , ages

ranging from 3 to 67 years (mean age. 36 years). All

patients presented with tender neck swelling and had

a variable degree of fever and leukocytosis. The

underlying cause or condition was obtainable from

medical history in ten patients; dental (lower third

molar) infections in three , upper respiratory tract in­

fections in three. and foreign body. infected

hematoma. infected surgica1 wound , and diabetes

mellitus each in one patient. Operation was done in

ten patients. In another one patient the diagnosis

was based on the clinical and CT findings and the

clinical improvement after the administration of an-

* Department of Otorhinolaryngology, College of Medicine , Gyeongsang National University

이 논문은 1990년 II월 30일 접수하여 1991년 2월 1 3일에 채택되었음

Received November 30. accepted February 13 , 1991

- 199-

Journal of Korean Radiolog’cal Society 1991; 27(2): 199-205

CT. even though the individuallayers of the deep cer­

vical fascia per se could not be seen. In all case. adja­

cent two or more cervical spaces were involved with

some preferential pathways according to their

etiologic events. In three cases with dental infection

ofthe lower third molar. the submylohyoid space was

unanimously involved. from which infection spread

to other related spaces (Case 1.2 and 5) (Fig. 1. Fig.

2). In three cases with upper respiratory tract infec­

tion. the anterior andlor posterior visceral spaces

were involved with other contiguous spaces (C잃e3.4

and 11) (Fig. 3. Fig. 4). In one case associated with fishbone injury to the mouth floor. the sublingual 킹ld

a submylohyoid spaces were involved with other spaces (Case 8) (Fig. 5). Each one case of infected

hematoma and infected surgical wound had the le-

The CT findings and corresponding etiologic sion at the spaces closely related to previous trauma

events are summarized in Table 1. lnfection was most and surgery. respectively (Case 7 and 9). There were

frequent at the transhyoid neck. i.e. both at the three cases of the midline crossing of the infection.

suprahyoid and infrahyoid levels. seen in seven cases. in two ofwhich it occurred anteriorly probably either

It was confined to the suprahyoid neck in two cases. through the superfici외 space of the neck or through

and to the infrahyoid neck in another two cases. The the disrupted superficial layer of the deep cervical

precise location and extent of infection in respect to fascia (Case 6 and 8) (Fig. 6). In the other case it oc-

the anatomical spaces could be clearly identified on curred posteriorly through the retropharyngeal space

tibiotics. Specific organisms were cultured in six

among surgically proven ten patients

CT was perforrned on a 9800 scanner (GE Medical

System. Milwaukee) with a routine use ofintravenous

contrast material. Only axial scans were obtained

with either 5 mm or 1 cm slice thickness and inter­

val through the region of interest. The gantry angle

was modified to minimize artifacts from dental reconstructions. CT was analyzed with a special

reference to the location and extent of infection. the

presence or absence of a drainable abscess with or

without gas bubbles. and. if any. associated findings

or complications.

Results

Fig. 1. Case 1. Deep neck infection due to the infected lower third molar. a. Axial scan through the mouth 110or. An air pocket is seen at the right submylohyoid space. lateral to the mylohyoid muscle (arrow). b. Axial scan 1 cm inferior to a. Gas bubbles associated with a rim enhancing abscess are also seen at the right sublingual space. between the mylohyoid muscle laterally (ar­row) and the geniohyoid muscle medially (double arrows). a b

m

」u

h E

n C

아 O

m d

n n

R ‘”

[ ·n

n n f j

a t

기 .J

A

d

”“

「

nm

m m “i

m m

.퍼‘

m

땅.m

L

R

야

?따

T

n

윗·mm m ”m

따 Y

얀.

R

m

b

m

j

f

a ‘e

]

a t k (

F

ι

”

U w

h

m 히 때 m‘띠 w ph

t

l

ιν

때

b

h“

않 W

M페 때 나없 때 폐 퍼 빠 찌

m‘.얹 때)내 m h

·떠 F염 싫 ，잉

”… iR

·밍 m

않 치 m m ιν m“

m

끊 핑 m

때 니

?ω ￡

D eR

m ”찌 m U e

땅 끼‘

t

E

빼

비 m

-)

·U

l

히

·ι h•h

π g h

야 씨

b

s

f

r i

s gt

3 “ 3 v 1

i }

e e

3

L k n g a j

.n

τ 1

K

￡

표 h

g nu

e

α‘

h 이

n m

” --

지 m

c

빠 M

빠 뼈 때 뼈 때 빠 빼 때 m

쩌

‘‘ ‘l

u x

-‘, n e f

」n,

이〕 πR

u e

g r

·따

A

m

잃 hm

빠 야한t mω

m

“냐

…a

뀐 m m a m m K

야 m

•l m m

뺑“←빠

ιM 빼

이 1때

’ m

띠

씨，

뼈‘ια

때 }아 때 -

-A 띠 히 O

빼·폐 때 Mω

m m 깨 -

않 하 m

%

때 써

1

리 M

얹

mm

u r

b e ·m

π

뼈 않 빼

h

tj ” ·ψ

k

뼈

c a n 獅빼

때

뺑 뼈 빼

비← ιι 셔ω

백 m

빽

짧 빼 뼈

a

삐 Lμ

%

Hyung Jin Kim , et al : Computed Tomography of Deep Neck Infections

(Case 4) (Fig. 3a). found in five cases. two of which presented them

CT correctly differentiated abscess from cellulitis. within the carotid sheath as well as other spaces of

and demonstrated an abscess in all surgically proven the neck. In these two cases CT additionally showed

ten cases. In one case in which CT also showed a a compressed or nonenhancing portion of the inter-

sizable abscess. symptomatic improvement was nal jugular vein during its course and surgery con-

followed by the administration of antibiotics. so firmed jugular vein erosion accompanied by

surgerγ was obviated (Case 10). The gas bubbles were thrombosis in both cases (Case 4 and 6) (Fig. 6).

•m

셔뼈 따 빠 뼈 않 따“빵때

뼈 쩌 때 뼈때 써한

미 u

o n PO

디 .m n

안 π‘

E 안

끼

-짜 따 n h”

?M

G

t

떠 야 때 얹 ”m

예뿔m ’ R

“ α ·x uk

h

양 아 t

갱 1

l

…… 4e

“

미 .잉 이 O

b

땅 m

‘ P n

η‘ m K

m Rm

a

R

m

따 m 뎌 r

얘“ e L

’ m m a n U

n

m씨

내 ιu n t e e

죄 l

f

t 1

a 1

·ι

%

매‘

3 h

때 m

·따 삐 R

따 m

이’t ”mh

gm

k L %

n

따 t I‘k

ζ‘ e c 3

·m

π w

.$

[

i “----i

1

1

i l

t

L

7

1

I

rκ g a o g

r

π c g

ν n w i

S

A ”m m k C

떠 떠 F

，없 때ι따 삐 따 땅앉 ιm

…m

」앉

g l

따 %

띠 m

mm

”m T

m ·m ”m·n

삐

c a

p-따 q mm

a g mm

야 n k v

α m

b

q&

m

마 h잉 뼈 잃 뻐 ·m

￠r.

m ”m

π“뼈 FH싸씨 젤

γ내냐 t

πg

갖 연 e

4” a e

「b

니시

시

빠삐 ’ W

“ a m

-이 빠 따 깨 MFM

빠 ‘jm따 뼈)

熾뼈

웠 때

Q]

‘ι

때 빼 빼

s

ιι h

m

뼈 빠

f‘

i’ ””

M

때 펴

L

μ ι…

1내내 ‘,‘

r

e a

웹 m

hm

에“

μm 없

뼈 따 때

l

c o

職빠 빼

PL

e y

$

m m ·내

없 뼈 뺑 뼈

뼈 m

뼈 뼈

廳삐 뼈 때

피 따 써빠

m

t l ,‘ 1

때 뼈났 짜

a b

Table 1. Summary of CT Findings and Etiologic Events of Deep Neck Infections

No/Age/Sex Anatomic spaces involved Abscess Gas Associated findings Etiologic events

suprahyoid

1I26/F submylohyoid. sublingua\ + + Submenta\ LlN Denta\ (3rd molar)

S. aureus

2/57/f submylohyoid. sublingua\ + + Submandib비ar and Denta\ (lower 3rd molar)

submenta\ LlN S.viridans

transhyoid

3/65/m anterior viscer외. retropharyngea\ + Airway compromise URl 4/24/m retropharyngea\. viscer외 + + Mediastina\ invasion URI

vascular. paraspin외

5/33/m submylohyoid. parap따ynge외， + Airway compromise. Dental (lower 3rd molar)

retropharyngeal. masticator. superfici머 Jugulodigastric & Streptococci

submandibular LlN

6/44/m viscer며 vascular. retropharyngea\. + + Jugular vein thrombosis DM

paraspin외. SCM. superfici외 Klebsiella

7/7/m SCM. paraspina\ + LlN in posterior triangle Infected hematoma

8/67/m sub1ingua\. submylohyoid. SCM. + + Fishbone trauma to

superfici외 mouth floor

9/211m submylohyoid. 킹lterior viscera\. + submenta\ LlN Infected surgica\ wound

superficia\ S.viridans

infrahyoid

10/46/m anterior viscera\. retropharyngea\ + Unknown

11l3/f retropharyngeal. anterior viscer외 + Mediastina\ extension URI H.influenzae

Note: LlN: lymph nodes URI: upper respiratoη tract infection DM : diabetes mellitus

- 201-

Journal of Korean Radiological Society 1991 ; 27(2) : 199-205

a b

Fig.4. Case 11. Deep neck infection following the pharyngeal infection. Pre-(a) and post-enhanced (b) scans through the thyroid glands show the multiseptated abscess involving both the left anterior and posterior visceral spaces. displacing the neck vessels and sternoc1eidomastoid musc1e laterally and trachea to the left. The anteriorly displaced and compressed ipsilateral thyroid gland is well visualized on the pre­enhanced scan (arrows in a) .

5a 5b 6 Fig. 5. Case 8 . Deep neck infectin following a fishbone injury to the mouth floor. a. Axial scan at the level of the superior aspect of the hyoid. The abscess containing gas bubbles involves the left sublingual (arrow) and submylohyoid (arrowheads) spaces. b . Axial scan through the thyroid cartilage. The abscess extends anteroinferiorly a10ng the fascia1 pl없les of the strap musc1es causing disruption of the platysma musc1e (arrow) . Note the ragged appearance of the anterior aspect of the ipsilateral sternoc1eidomastoid musc1e due to the destructive process (arrowheads). Fig. 6. Case 6 . Deep neck infection complicated by the jugular vein thrombosis. This 43-year-old diabetic had an extensive necrotizing inflammation involving the deep and superficial neck spaces. Note the dirty fluid collection interspersed with gas bubbles. lateral to the left common carotid artery and behind the tattered stemoc1eidomastoid musc1e in the area of the internal jugular vein (arrows).

In addition to the vascular involvement. CT often spaces surrounded by it (6-10). Needless to say. a

helped us recognize other c1inically significant com- comprehensive understanding of their anatomy is

plications of cervica1 infections. These were two cases crucia1 to evaluate CT and the clinical status of pa-

ofmediastinal involvement (Case 4 and 11) (Fig. 3c). tients with deep neck infection.

two cases of airway encroachment (Case 3 and 5). 와ld The anatomic details of the deep cervica1 fascia are

five cases of enlarged cervical lymph nodes (Case too complex to be dealt with in this context precise-

1,2 .5.7 and 9) (Fig. 2). ly. In short. the cervica1 fascia consists of a superficia1

fascia and a deep fascia. The superficia1 fascia is a fat­

ty layer of subcutaneous tissue enclosing the

Discussion platysma musc1e. Superiorly it extends to enc10se the

superficial voluntary musc1es of the face and scalp.

Since the advent of antibiotics. the incidence of and inferiorly it extends to be continuous with the

deep neck infections have dec1ined continuously. but superficial fascia of the throax and axilla. The deep

even now they sometimes make trouble for a physi- fascia is divided into three layers. namely. superfici외.

cian in both diagnosis and treatment. Since the first middle. and deep. The superficiallayer of the deep

description by Tillaux in 1882. that the deep cervica1 fascia. also ca1led as the investing layer. attaches in-

fascia is made up of three layers (superficial. middle. feriorly to the sternum. c1avic1e and scapula. and

and deep). a lot of investigations have been made to crosses the midline anteriorly. encirc1ing the neck to

elucidate the anatomy of deep cervical fascia and attach to the spines ofthe cervica1 vertebrae posterior-

- 202-

Hyung Jin Kim. et al: Computed Tomography of Deep Neck Infections

ly. Anterosuperiorly. it attaches to the body of the

hyoid bone and further superiorly to the body of the

mandible. and further superoposteriorly to the

zygoma and the occiput. It envelopes two glands

(parotid and submandibular). two muscles (ster­

nocleidomastoid and trapezius). and two spaces (the

suprastern외 space of Burns and the subvagina1 space

ofthe posterior triangle) on its way. and hence is best

remembereq by “ the rule oftwos". The middle layer

of the deep fascia. also called as the visceral or buc­

copharyngeal layer. can be divided into two parts.

musc비ar and visceral. The muscular part attaches

inferiorly to the sternum. clavicle and scapula. and

superiorly to the hyoid bone and thyroid cartilage.

enclosing the strap muscles. The visceral part at­

taches superiorly to the base of the skull on the

posterior aspect. and to the hyoid bone on the anterior

aspect. encircling the thyroid gland. trachea. and

esophagus. It fuses with the 외ar division of the deep

layer of the deep cervical fascia posteroinferiorly at

the level of Tl or T2. and forms the anterior boun­

dary of the retropharyngeal (or posterior visceral)

space of the neck. The deep layer of the deep fascia

extends from the base of the skull superiorly to the

coccyx inferiorly . encompassing the preveπebral

muscles and the deep muscles of the posterior

triangle. and consists of two divisions. alar and

prevertebral. The alar division forms the posterior

boundary of the reσopharyngeal space 하ld fuses with

the middle layer at Tl or T21evel. The prevertebral

division forms the anterior boundary of the

prevertebral space containing the prevertebral

muscles and the phrenic nerve. The space between

the alar and prevertebral divisions is the so-called .

“ danger space". The carotid sheath is made up ofthe

above three layers of deep cervical fascia and extends

from the base of the skull superiorly down into the

chest.

The hyoid bone is the most important structure

in the neck which limits the spread ofinfection (11).

Neck spaces sharing both the suprahyoid and in­

frahyoid neck inc1 ude the superficial.

retropharyngeal. prevertebral. and carotid spaces.

Spaces within the suprahyoid neck only include

parapharyngeal. sublingua l. submylohyoid.

masticator. temporal. parotid. and peritonsillar

spaces. Space within the infrahyoid neck only in­

cludes anterior viscera1 space (10). In this series. the

level of infection was most frequent at the transhyoid

neck. seen in seven cases. longitudinally traversing

the hyoid bone through the retropharyngeal space

posteriorly. the superficial space anteriorly. or

through the carotid space.

1he sources of deep neck infections are. in roughly

speaking. dental infections in 30%. pharyngea1 infec­

tions in 30%. and other minor conditions such as der­matologic problems. otitis. cervical adenitis. and

trauma in remaining 40% (10.12). which are very

similar to our cases. In addition. there were somewhat

common spaces involved according to the etiologic

events. In this series. three patients with the lower

third molar infections had a lesion in the sub­

!TIylohyoid space unanimously (Fig. 1. Fig. 2). all of

three patients with pharyngeal infections in the

posterior and/or anterior visceral spaces (Fig. 3. Fig.

4). and one patient with a fishbone injury to the

mouth floor in the sublingual 킹1d submylohyoid

spaces (Fig. 5). Anatomically. in the region of the

mandibular and maxillary molars. the buccinator

muscle serves as a barrier against the spread of den­

tal infections. It attaches to the alveolar processes of

the maxilla above and to the mandible below. In per­

sons whose mandibular or maxillary molars have

long roots extending beyond the buccinator attach­

ment. infection can reach the buccal space with ease.

from which it can spread into the masticator space

(8 .9). The relation of the apices of the mandibular

teeth to the mandibular attachment of the mylohyoid

muscle is equally important in dental infections. In

general. the roots of the second and third molars ex­

tend beyond the mylohyoid ridge. while the roots of

the anterior ones never reach so far. Consequently.

dental infections anterior to the second molar tend

first to involve the sublingal space. while those ofthe

second or third molars can directly involve the sub­

mylohyoid space (8.9.13). The sublingual and sub­

mylohyoid spaces are separated by the mylohyoid

muscle. but are freely communicating posteriorly

each other. making the infection of the mouth floor

easily involve the submylohyoid space.

It is important to differentiate abscess from

cellulitis. in that no drainage should be attempted

during the stage of cellulitis (1.2). CT accurately

demonstrated an abscess as a discrete low density le­

sion with or without peripheral rim enhancement.

while cellulitis was seen as soft tissue swelling with

obliteration of adjacent fascial planes witho

- 203-

Journal of Korean Radiological Society 1991; 27(2): 199-205

demonstrated gas bubbles which might favor an in- puterized tomography. Laryngoscope 1982;

fectious process in five patients. 92:630-633 The most important role ofCT in the realm of deep 3. Merhar GL. Colley DP. Clark RA et a l. Computed

neck infections is probably the identiflcation of poten - tomographic domonstratlon of cervical abscess and

tially life-threatening compllcations. such as airway jugular vein thrombosis. Arch Otolaryngol 1981 ;

encroachment. ‘ Jugular vein thrombosis. 107:313-315

mediastinitis. peri떠rditis. empyema. carotid blow 4 . Wenig BL. Shikowitz J. Abramson AL. Necrotizing

out. or intracranial extension (1,2 .4.11). We ex- fasclitls as a lethal complicatlon of peritonsillar

perienced each two cases of airway encroachment. abscess. Laryngoscope 1984; 94:1576- 1579

jugular vèin thrombosis (Fig. 6). and mediastinal in- 5. Hardin CW. Harnsberger HR, Osborn AG et a l. In-

volvement cFig.3b). The routes of spread of space .in- fection and tumor of the mastlcator space: CT

fections of tlÌe head and neck into the chest. according evaluatlon. Radiology 1985; 157 :413-4 17

to Wills and Vernon. are in three ways: that is. byen- 6. Grodinsky M. Holyoke EA. Fasciae and fascial

try of the infection into the parapharyngeal space spaces of head. neck and a여acent regions. Am J

which leads1ndirecUy to the mediastinum. byaspira- Anat 1938; 63:367-408

tion of the infected material into the bronchial tree 7. Levitt GW. Cervical fascia and deep neck infections.

or the development of a sinus entry into the Laryngoscope 1970; 80:409-435

tracheobronchial apparatus. or by the septic em- 8. Spill‘a CJ. Pathways of dental infections. J Or려 Surg

bolism (11). In our two cases having mediastinal ex- 1966; 24:111-124

tension. it seemed to occur via the anterior visceral 9 . Paonessa DF. Golstein JC. Anatomyand physiology

space and carotid space. respectively. of head and neck infections (with emphasis on the

In conclusion. in the evaluation of deep neck in- fascia of the face and neck). Otolaryngol Clin North

fecitons. CT can correcUy provide valuable informa- Am 1976; 9:561-580

tions about the location and extent of infection. 10. Everts EC. Echevarria J. Diseases of the pharynx

presence or absence of a drainable abscess. and and deep neck infections. In: Paparella MM.

associated complications.and thus help a physician Shunrick DA. eds. Otolaryngology. Head and Neck.

guide medical or surgical manageme

- 204-

〈국문요약〉

Hyung Jin Kim. et al : Computed Tomography of Deep Neck Infections

심부 경부감염의 전산화단층촬영 소견

경상대학 의과대학 방사선과학교실 .. 이비인후과학교실

김형진 · 정혜경 • 검재형 • 황의기 전시영 •. 정성훈

저자들은 지난 19개월동안 경상대학병원에서 심부 경부감염으로 진단된 11명의 환자를 대상으로 CT소견올 분석

하였고 특히 감염의 위치와 범위， 배액 가능한 농양의 유무， 그리고 동반된 합병중의 유무에 그 주안점을 두었다.

CT로 심부 경부 근막의 각 충들은 판찰할 수 없었으나 경부공간올 침범한 감염의 위치와 범위는 정확히 알 수 있

었다. 껄골(hyoid bone)을 기준으로 감염이 셜골의 상부와 하부에 같이 있었던 경우가 7례로 가장 많았고 셜골의 상

부와 하부에 각각 국한되어 있었던 경우가 2례씩 있었다. 감염의 원인 질환에 따라 공통된 경부 공간의 침범을 관찰

할 수 있었는데， 하악의 제 3구치의 감염이 있었던 3례 모두에서 악얼골 하강(submylohyoid space)의 청범이 있었

고， 상기도 감염으로 인한 3혜 모두에서 장기 전강(anterior visceral space) 또는 장기 후강(posteriòr visceral space)

에 염중이 판찰되었으며， 생선가시로 인한 구저 (mouth floor) 손상 l례에서는 셜하강(sublingual space)파 악셜골 하

강이 함께 칭범되어 있었다. CT는 수술로 확진된 10혜 모두에서 배액 가농한 농양의 존재를 쉽게 발견케 하였고 이

중 5혜는 공기 음영도 함께 판찰되었다. 또한 동반된 합병중을 찾는데에도 CT는 크게 유용하였는바 상종격동 침범

이 2례， 기도 협착이 2혜， 경정맥 혈전중이 2헤， 반웅성 경부 엄파절 비대가 5례 있었다. 결론적으로， CT는 심부

정부감염을 명가하는데 있어서 감염의 위치와 범위 ， 농양의 유무， 동반된 합병중풍을 정확히 예견케 함으로써 외과

적 또는 내과적 치료를 보다 효율적으로 하게 하는 매우 유용한 진단방법이라고 생각된다.

- 205-