Presentation on theme: "Imaging in Acute Torticollis"— Presentation transcript:
1Imaging in Acute Torticollis Division of NeuroradiologyDepartment of RadiologyUniversity of North Carolina at Chapel Hill
2Overview of This Presentation IntroductionImaging algorithm for acute torticollisCauses of torticollisTraumaInfection/InflammationNeoplasmOther/IdiopathicAtlantoaxial rotatory fixationSelected references
3At the Conclusion of this Exhibit One Should Be Able To: Define torticollisDescribe an algorithm for imaging patients presenting with torticollisList several potential causes of torticollis and describe their typical imaging featuresDiscuss the concept of atlanto-axial rotatory fixation and its diagnosis
4Introduction: 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.
5Introduction: Clinical Aspects of Acute Torticollis Torticollis refers to a symptom rather than a distinct disease processIt can be caused by a wide variety of conditions (over 80 causes have been described) which range from relatively innocuous to life-threateningMay be congenital or acquiredOccurs more frequently in children than in adultsThe right side is affected in 75% of patients
6Introduction: Chronic Sequelae of Torticollis PhysicalPositional plagiocephalyFacial deformitiesCervical spine degenerationRadiculopathies and myelopathiesPsychiatricMajor depressionAgoraphobiaSubstance abuseOCD
7Imaging 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.
11Traumatic Causes of Torticollis: Fibromatosis Colli Rare form of infantile fibromatosis affecting sternocleidomastoid muscle (SCM)Accounts for >80% of childhood cases of torticollisDue to traumatic delivery or possibly abnormal head position in uteroInfants usually appear normal at birth, torticollis develops in the 2-3rd weeks of lifeMore common in males and in right sideSonographic findings are typical
12Traumatic 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
13Traumatic 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).
14Traumatic Causes of Torticollis: Unilateral Interfacetal Dislocation Axial CT image and a saggital reformatted imagedemonstrate right facet dislocation (arrows).
15Traumatic 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.
16Occipital Condyle Fractures Classified into 3 types by Anderson and MontesanoI Axial loading fracture limited to the occipital condyle without displacement into foramen magnumII Fracture of basiocciput extending into occipital condyleIII Small fragment arising from medial surface of condyle avulsed by an intact alar ligament and distracted towards dens
17Infectious and Inflammatory Causes of Torticollis CNS relatedMeningitisHead and Neck relatedUpper respiratory infectionsOtitis mediaMastoiditis/Bezold’s abscessCervical adenitisRetropharyngeal abscessSpine relatedVertebral osteomyelitis and/or discitisEpidural abscessRheumatoid arthritis
18Infectious 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).
19Bezold’s AbscessRare complication of suppurative mastoiditis occuring when infection erodes the mastoid tip into the neck, forming an abscessMay cause spasm of the SCM, resulting in torticollisAbscess may spread down the plane of the sternocleidomastoid muscle into the lower neckAlso associated with cholesteatomas
20Infectious 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.
21Infectious Causes of Torticollis: Discitis and Osteomyelitis T1 post-Gd
22Inflammatory 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.
23Neoplastic Causes of Torticollis CNS tumorsSpinal cord or brainstem tumorsPosterior fossa tumors and cystsVestibular schwannomaMetastasesBone tumorsVertebral eosinophilic granulomaOsteoid osteoma/osteoblastomaMetastases (spine or skull base)
24Neoplastic Causes of Torticollis: Spinal Cord Tumor Sagittal enhanced T1 MRI of the cervical spine demonstrates an enhancing, expansile ganglioglioma in a 10- year-old female presenting with acute torticollis.
25Neoplastic 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.
26Other Causes of Torticollis Dystonic syndromes (idiopathic spasmodic torticollis)Chiari 1 malformationSyringomyeliaNeuroleptic drug reactionsCongenital vertebral anomalies (e.g. – congenital scoliosis, cervical segmentation anomalies, Klippel-Feil syndrome)Hemifacial microsomiaOculomotor nerve palsies/StrabismusGastroesophageal reflux (Sandifer’s syndrome)Vascular abnormalities (craniocervical AV fistula; congenital hypoplasia of the internal carotid artery)Pseudotumor cerebri
27Other Causes of Torticollis: Chiari I Malformation Unenhanced midsagittal T1 weighted MR image shows significant downward displacement of peg-shaped cerebellar tonsils (arrowhead) through foramen magnum (type I Chiari malformation).
28Other 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.
29Chiari I MalformationDefined as greater than 5 mm of displacement of triangular-shaped cerebellar tonsils below the foramen magnumBelieved to be due to an abnormality of expression of spinal segmentation genes that lead to varying degrees of hypoplasia of the skull baseUnclear if torticollis is due to associated skeletal abnormalities or due to compression of brainstem and lower cranial nervesTorticollis may be caused by syringohydromyelia even in absence of a Chiari malformation
30Other 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
31Klippel-Feil Syndrome Heterogeneous group of conditions unified by presence of congenital synostosis of some or all cervical vertebraeClassic 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 abnormalitiesAlong with congenital scoliosis, accounts for nearly 1/3 of nonmuscular causes of torticollis in childrenCervical anomalies are well characterized by CT
32Idiopathic Spasmodic Torticollis (IST) Also referred to as cervical dystoniaNontraumatic, acquired form of torticollis presenting as spasms or jerks of SCMsFemales more commonly affected by 4.5:1Typically occurs in adults over age 30Diagnosis requires exclusion of other potential causes of torticollis and that symptoms be present for at least 6 monthsConventional neuroimaging studies usually negative
33Idiopathic Spasmodic Torticollis (IST) Although pathophysiology of IST is not understood, the interstitial nucleus in the brainstem has been implicated as a probable site of abnormalityIST may be due to abnormalities of the basal ganglia, vestibular systems, or spinal accessory nervesProton MR spectroscopy in IST patients may demonstrate diminished n-acetyl-aspartate (NAA) levels in basal ganglia when compared with normal controls
34Proton MR Spectroscopy in Idiopathic Spasmodic Torticollis Long echo time proton MRS at level of left basal ganglia (left) demonstrates low level of n-acetyl-aspartate relative to normal right basal ganglia (right).
35Atlanto-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 rare75-80% of reported cases occur in childrenCompression of spinal cord may occur if there is anterior or posterior displacementVertebral artery kinking or stretching may occur and cause posterior circulation ischemic symptoms
36Atlanto-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 regionIt 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
37Types of Atlanto-axial Rotatory Fixation (Fielding classification) Type 1 Rotatory fixation w/o anterior displacement of atlas (intact transverse and alar ligaments) – most common typeType 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)
38Types 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: (Used with permission)
39Radiographic Diagnosis of Atlanto-axial Rotatory Fixation CT is essential for imaging of AARFWhen rotation is accompanied by anterior or posterior displacement (Fielding types 2-4), CT is diagnosticType 1 rotatory fixation appears identical to other causes of torticollis when patients are imaged at restThus, patients with suspected type 1 AARF should be scanned at rest and with maximal voluntary contralateral head rotatationCT in patients with AARF shows little or no change in position of atlas with respect to axis
40Type 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.
41Selected ReferencesAnderson 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: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; 59:37-44.Kraus R, Han BK, Babcock DS, Oestreich AE. Sonography of neck masses in children. AJR Am J Roentgenol 1986; 146:Roche CJ, O’Malley M, Dorgan JC, Carty HM. A Pictorial Review of Atlanto-axial Rotatory Fixation: Key points for the radiologist. Radiographics 2001; 56:Tracy MR, Dormans JP, Kusumi K. Klippel-Feil Syndrome: Clinical features and current understanding of etiology. Clin Orthop Relat Res 2004; 424: