Transcript Imaging in Acute Torticollis

Imaging in Acute
Torticollis
Division of Neuroradiology
Department of Radiology
University of North Carolina at Chapel Hill
Overview of This Presentation
I.
II.
III.
Introduction
Imaging algorithm for acute torticollis
Causes of torticollis
A.
B.
C.
D.
IV.
V.
Trauma
Infection/Inflammation
Neoplasm
Other/Idiopathic
Atlantoaxial rotatory fixation
Selected references
At the Conclusion of this Exhibit
One Should Be Able To:
• Define torticollis
• Describe an algorithm for imaging patients
presenting with torticollis
• List several potential causes of torticollis
and describe their typical imaging features
• Discuss the concept of atlanto-axial
rotatory fixation and its diagnosis
Introduction: What is Torticollis?
• Derived from the
Latin tortus (twisted)
+ collis (neck or
collar)
• Torticollis is defined
as abnormal
twisting of the neck
which causes the
head to be held in a
rotated or tilted
position.
Introduction: Clinical Aspects of
Acute Torticollis
• Torticollis refers to a symptom rather than a
distinct disease process
• It can be caused by a wide variety of conditions
(over 80 causes have been described) which
range from relatively innocuous to lifethreatening
• May be congenital or acquired
• Occurs more frequently in children than in adults
• The right side is affected in 75% of patients
Introduction: Chronic Sequelae of
Torticollis
• Physical
– Positional plagiocephaly
– Facial deformities
– Cervical spine degeneration
– Radiculopathies and myelopathies
• Psychiatric
– Major depression
– Agoraphobia
– Substance abuse
– OCD
Imaging of Patients with Torticollis
• Choice of imaging studies depends on age and if
history of trauma is present.
• In newborn infants with congenital muscular torticollis,
ultrasound is preferred and often diagnostic.
• In older children and adults with post trauma torticollis,
CT of neck/cervical spine is needed to exclude
fracture or malalignment. If CT is positive, MRI and
MRA of the neck should be considered to evaluate for
associated cord, ligamentous, or arterial injuries.
• In older children and adults presenting with torticollis
without trauma, neck/cervical spine CT is the initial
imaging study; if negative, then brain and cervical
spine MRI is performed to exclude a CNS cause of
torticollis.
Imaging Algorithm for Acute Torticollis
Patient with
torticollis
Older child or
adult
Newborn infant
Ultrasound
Negative
Positive
CT or MRI of
neck
Stop
Trauma
No trauma
CT neck and/or
cervical spine
CT neck and/or
cervical spine
Negative
Positive
Positive
Negative
Stop
MRI C-Spine
MRA neck
Stop
MRI C-spine
MRI brain
Causes of Torticollis
Traumatic Causes of Torticollis
• Muscular
– Fibromatosis colli
– Muscle spasm following trauma
• Skeletal
– Unilateral interfacetal dislocation (UID)
– Occipital condyle fractures
– Atlanto-axial rotatory fixation (? truly traumatic)
• CNS related
– Subarachnoid hemorrhage
– Spinal epidural hematoma
Traumatic Causes of Torticollis:
Fibromatosis Colli
• Rare form of infantile fibromatosis affecting
sternocleidomastoid muscle (SCM)
• Accounts for >80% of childhood cases of
torticollis
• Due to traumatic delivery or possibly abnormal
head position in utero
• Infants usually appear normal at birth, torticollis
develops in the 2-3rd weeks of life
• More common in males and in right side
• Sonographic findings are typical
Traumatic Causes of Torticollis:
Fibromatosis Colli
Longitudinal US views of the
right (top) and left (bottom)
SCMs in an infant with
torticollis. The right SCM is
enlarged and of
heterogeneous echotexture.
The left SCM is normal.
There are mildly enlarged
lymph nodes posterior to the
left SCM
Traumatic Causes of Torticollis:
Fibromatosis Colli
Axial contrast CT in an infant with fibromatosis colli.
The right SCM is enlarged and has faint central
enhancement (arrowhead).
Traumatic Causes of Torticollis:
Unilateral Interfacetal Dislocation
Axial CT image and a saggital reformatted
imagedemonstrate right facet dislocation (arrows).
Traumatic Causes of Torticollis:
Occipital Condyle Fracture
Axial and coronal reformatted CT images show a right
occipital condyle fracture (type III) in a patient presenting
with acute torticollis after trauma.
Occipital Condyle Fractures
• Classified into 3 types by Anderson and
Montesano
I
Axial loading fracture limited to the occipital
condyle without displacement into foramen
magnum
II Fracture of basiocciput extending into
occipital condyle
III Small fragment arising from medial
surface of condyle avulsed by an intact alar
ligament and distracted towards dens
Infectious and Inflammatory
Causes of Torticollis
• CNS related
– Meningitis
• Head and Neck related
–
–
–
–
–
Upper respiratory infections
Otitis media
Mastoiditis/Bezold’s abscess
Cervical adenitis
Retropharyngeal abscess
• Spine related
– Vertebral osteomyelitis and/or discitis
– Epidural abscess
– Rheumatoid arthritis
Infectious Causes of Torticollis:
Mastoiditis/Bezold’s Abscess
Unenhanced (right) and enhanced (left) axial CT images
in a patient with acute torticollis and right ear pain
demonstrate coalescing mastoiditis eroding medial
surface of mastoid (arrow). Inferior to this is an abscess
involving the right SCM (arrowhead).
Bezold’s Abscess
• Rare complication of suppurative mastoiditis
occuring when infection erodes the mastoid tip
into the neck, forming an abscess
• May cause spasm of the SCM, resulting in
torticollis
• Abscess may spread down the plane of the
sternocleidomastoid muscle into the lower neck
• Also associated with cholesteatomas
Infectious Causes of Torticollis:
Suppurative Adenitis
Enhanced axial fat
suppressed T1 MR
image demonstrates a
necrotic retropharyngeal
lymph node (arrowhead)
in a child with
suppurative adenitis
presenting as acute
torticollis.
Infectious Causes of Torticollis:
Discitis and Osteomyelitis
T2
T1 post-Gd
Inflammatory Causes of Torticollis:
Rheumatoid Arthritis
Unenhanced
sagittal T1 MR in a
patient with
rheumatoid arthritis
and torticollis.
There is pannus
destroying the dens
and compressing
the lower brainstem
and medulla.
Neoplastic Causes of Torticollis
• CNS tumors
– Spinal cord or brainstem tumors
– Posterior fossa tumors and cysts
– Vestibular schwannoma
– Metastases
• Bone tumors
– Vertebral eosinophilic granuloma
– Osteoid osteoma/osteoblastoma
– Metastases (spine or skull base)
Neoplastic Causes of Torticollis:
Spinal Cord Tumor
Sagittal enhanced T1
MRI of the cervical
spine demonstrates an
enhancing, expansile
ganglioglioma in a 10year-old female
presenting with acute
torticollis.
Neoplastic Causes of Torticollis:
Skull Base Tumor
Axial enhanced T1 MRI in an adult with acute
torticollis demonstrates a metastasis from renal
cell carcinoma (arrowheads) involving the left
occipital condyle.
Other Causes of Torticollis
•
•
•
•
•
•
•
•
•
•
Dystonic syndromes (idiopathic spasmodic torticollis)
Chiari 1 malformation
Syringomyelia
Neuroleptic drug reactions
Congenital vertebral anomalies (e.g. – congenital
scoliosis, cervical segmentation anomalies, Klippel-Feil
syndrome)
Hemifacial microsomia
Oculomotor nerve palsies/Strabismus
Gastroesophageal reflux (Sandifer’s syndrome)
Vascular abnormalities (craniocervical AV fistula;
congenital hypoplasia of the internal carotid artery)
Pseudotumor cerebri
Other Causes of Torticollis:
Chiari I Malformation
Unenhanced
midsagittal T1
weighted MR image
shows significant
downward
displacement of pegshaped cerebellar
tonsils (arrowhead)
through foramen
magnum (type I Chiari
malformation).
Other Causes of Torticollis:
Chiari I Malformation with a Syrinx
Unenhanced sagittal
T1 weighted image
demonstrates a
large, expansile,
multiseptated cyst in
the cervical cord of a
patient with a Chiari I
malformation and
torticollis.
Chiari I Malformation
• Defined as greater than 5 mm of displacement of
triangular-shaped cerebellar tonsils below the
foramen magnum
• Believed to be due to an abnormality of
expression of spinal segmentation genes that
lead to varying degrees of hypoplasia of the
skull base
• Unclear if torticollis is due to associated skeletal
abnormalities or due to compression of
brainstem and lower cranial nerves
• Torticollis may be caused by syringohydromyelia
even in absence of a Chiari malformation
Other Causes of Torticollis:
Klippel-Feil Syndrome
Lateral radiograph of
the cervical spine
shows hypoplasia and
fusion of lower cervical
vertebrae in a patient
with Klippel-Feil
syndrome and
torticollis
Klippel-Feil Syndrome
• Heterogeneous group of conditions unified by presence
of congenital synostosis of some or all cervical vertebrae
• Classic triad described by Klippel and Feil consisting of
short neck, low posterior hairline, and limited range of
motion of neck (seen in <50% of patients)
• Commonly associated abnormalities include congenital
scoliosis, rib abnormalities, deafness, genitourinary
abnormalities, Sprengel’s deformity, and cardiac
abnormalities
• Along with congenital scoliosis, accounts for nearly 1/3
of nonmuscular causes of torticollis in children
• Cervical anomalies are well characterized by CT
Idiopathic Spasmodic Torticollis
(IST)
• Also referred to as cervical dystonia
• Nontraumatic, acquired form of torticollis
presenting as spasms or jerks of SCMs
• Females more commonly affected by 4.5:1
• Typically occurs in adults over age 30
• Diagnosis requires exclusion of other potential
causes of torticollis and that symptoms be present
for at least 6 months
• Conventional neuroimaging studies usually
negative
Idiopathic Spasmodic Torticollis
(IST)
• Although pathophysiology of IST is not
understood, the interstitial nucleus in the
brainstem has been implicated as a probable
site of abnormality
• IST may be due to abnormalities of the basal
ganglia, vestibular systems, or spinal accessory
nerves
• Proton MR spectroscopy in IST patients may
demonstrate diminished n-acetyl-aspartate
(NAA) levels in basal ganglia when compared
with normal controls
Proton MR Spectroscopy in
Idiopathic Spasmodic Torticollis
Long echo time proton MRS at level of left basal
ganglia (left) demonstrates low level of n-acetylaspartate relative to normal right basal ganglia (right).
Atlanto-axial Rotatory Fixation
• Atlanto-axial rotatory fixation (AARF) is a
controversial entity - Is it the result of or the
cause of torticollis?
• True atlanto-axial subluxation or dislocation is
rare
• 75-80% of reported cases occur in children
• Compression of spinal cord may occur if there is
anterior or posterior displacement
• Vertebral artery kinking or stretching may occur
and cause posterior circulation ischemic
symptoms
Atlanto-axial Rotatory Fixation
• Frequently, there is an antecedent history of
trauma or upper respiratory infection
• “Grisel’s syndrome” = non-traumatic atlanto-axial
subluxation secondary to ligamentous laxity and
inflammation following infection or surgery in the
head and neck region
• It has been postulated that swollen capsular and
synovial tissues and muscle spasm prevent
reduction early on and that ligament and
capsular contractures develop later, ultimately
causing fixation
Types of Atlanto-axial Rotatory
Fixation (Fielding classification)
Type 1
Rotatory fixation w/o anterior
displacement of atlas (intact transverse
and alar ligaments) – most common type
Type 2
Rotatory fixation with 3-5 mm of anterior
displacement of atlas (implies deficiency
of transverse ligament)
Type 3
Rotatory fixation with >5 mm of anterior
displacement of atlas (implies deficiency
of both transverse and alar ligaments)
Type 4
Rotatory fixation with posterior displacement
of atlas (implies deficiency of odontoid
process)
Types of Atlanto-axial Rotatory
Fixation (Fielding classification)
From Lustrin ES, Karakas SP, Ortiz AO, et al. Pediatric cervical spine: Normal anatomy,
variants, and trauma. Radiographics 2003; 23:539-60. (Used with permission)
Radiographic Diagnosis of Atlantoaxial Rotatory Fixation
• CT is essential for imaging of AARF
• When rotation is accompanied by anterior or
posterior displacement (Fielding types 2-4), CT
is diagnostic
• Type 1 rotatory fixation appears identical to
other causes of torticollis when patients are
imaged at rest
– Thus, patients with suspected type 1 AARF should be
scanned at rest and with maximal voluntary
contralateral head rotatation
– CT in patients with AARF shows little or no change in
position of atlas with respect to axis
Type 1 Atlanto-axial Rotatory
Fixation
Axial CT image with head rotated to left shows widened
space between dens and right C1 lateral mass which
persists with rotation of head to right (arrowheads)
compatible with AARF. The atlanto-dental interval is
normal making this a type 1 AARF.
Selected References
Anderson PA, Montesano PX. Morphology and treatment of occipital condyle
fractures. Spine 1988; 13:731-6.
Ballock RT, Song KM. The prevalence of nonmuscular causes of torticollis in
children. J Pediatr Orthop 1996; 16:500-4.
Castillo M, Albernaz VS, Mukherji SK, Smith MM, et al. Imaging of Bezold’s
abscess. AJR Am J Roentgenol 1998; 171:1491-5.
Federico F, Lucivero V, Simone IL, Defazio G, et al. Proton MR spectroscopy
in idiopathic spasmodic torticollis. Neuroradiology 2001; 43:532-6.
Fielding JW, Hawkins RJ. Atlanto-axial rotatory fixation (fixed rotatory
subluxation of the atlanto-axial joint). J Bone Joint Surg Am 1977; 59:3744.
Kraus R, Han BK, Babcock DS, Oestreich AE. Sonography of neck masses in
children. AJR Am J Roentgenol 1986; 146:609-13.
Roche CJ, O’Malley M, Dorgan JC, Carty HM. A Pictorial Review of Atlantoaxial Rotatory Fixation: Key points for the radiologist. Radiographics 2001;
56:947-58.
Tracy MR, Dormans JP, Kusumi K. Klippel-Feil Syndrome: Clinical features
and current understanding of etiology. Clin Orthop Relat Res 2004;
424:183-90.