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Neck CTA - CAM 700

GENERAL INFORMATION

It is an expectation that all patients receive care/services from a licensed clinician. All appropriate supporting documentation, including recent pertinent office visit notes, laboratory data, and results of any special testing must be provided. If applicable: All prior relevant imaging results and the reason that alternative imaging cannot be performed must be included in the documentation submitted. 

Where a specific clinical indication is not directly addressed in this guideline, medical necessity determination will be made based on widely accepted standard of care criteria. These criteria are supported by evidence-based or peer-reviewed sources such as medical literature, societal guidelines and state/national recommendations.

Purpose
Indications for performing Computed Tomography Angiography (CTA) in the neck/cervical region.
 

INDICATIONS FOR NECK CTA
Cerebrovascular Disease
If there is a combination request* for an overlapping body part, either requested at the same time or sequentially (within the past 3 months) the results of the prior study should be:

  • Inconclusive or show a need for additional or follow up imaging evaluation OR
  • The office notes should clearly document an indication why overlapping imaging is needed and how it will change management for the patient.

*Unless approvable in the combination section as noted in the guidelines

INDICATIONS FOR NECK CTA
Cerebrovascular Disease

  • Recent ischemic stroke or transient ischemic attack (see Background)1,2,3
    • Note: For remote strokes with no prior vascular imaging, imaging can be considered based on location/type of stroke and documented potential to change management
  • Known or suspected vertebrobasilar insufficiency (VBI) in patients with symptoms such as dizziness, vertigo, headaches, diplopia, blindness, vomiting, ataxia, weakness in both sides of the body, or abnormal speech4,5,6
  • Asymptomatic patients with an abnormal ultrasound of the neck or carotid duplex imaging (e.g., carotid stenosis ≥ 70%, technically limited study, aberrant direction of flow in the carotid or vertebral arteries)7,8,9
  • Symptomatic patients with an abnormal ultrasound of the neck or carotid duplex imaging (e.g., carotid stenosis ≥ 50%, technically limited study, aberrant direction of flow in the carotid or vertebral arteries)7,10,11

Tumor/Pulsatile Mass

  • Pulsatile mass on exam12
  • Known or suspected carotid body tumors, or other masses such as a paraganglioma, arteriovenous fistula pseudoaneurysm, atypical lymphovascular malformation 12,13

Note: Ultrasound (US) may be used to identify a mass overlying or next to an artery in initial work up of a pulsatile mass.


Other Extracranial Vascular Diseases14

  • Large vessel vasculitis
    • Giant cell with suspected extracranial involvement14,15,16,17
    • Takayasu's Arteritis for evaluation at diagnosis and as clinically indicated for suspected extracranial involvement17
  • Subclavian steal syndrome when ultrasound is positive or indeterminate OR for planning interventions18
  • Suspected carotid or vertebral artery dissection; secondary to trauma or spontaneous due to weakness of vessel wall6,19,20
  • Follow-up of known carotid or vertebral artery dissection within 3 – 6 months for evaluation of recanalization and/or to guide anticoagulation treatment21,22
  • To identity an arterial source of bleeding in patients with hemorrhage of the head and neck6,23
  • Horner’s syndrome, non-central (miosis, ptosis, and anhidrosis)24,25
  • For evaluation of pulsatile tinnitus (subjective or objective) for suspected arterial vascular etiology26
  • For further evaluation of a congenital vascular malformation of the head and neck
  • Known extracranial vascular disease that needs follow-up or further evaluation

Pre- or Post-Operative/Procedural Evaluation
Pre-operative evaluation for a planned surgery or procedure

  • Pre-operative evaluation for a planned surgery or procedure

Post-operative evaluation for a planned surgery or procedure

  • A follow-up study may be needed to help evaluate a patient’s progress after treatment, procedure, intervention, or surgery. Documentation requires a medical reason that clearly indicates why additional imaging is needed for the type and area(s) requested


Further Evaluation of Indeterminant Findings
Unless follow up is otherwise specified within the guideline:

  • For initial evaluation of an inconclusive finding on a prior imaging report that requires further clarification
  • One follow-up exam of a prior indeterminate MR/CT finding to ensure no suspicious interval change has occurred. (No further surveillance unless specified as highly suspicious or change was found on last follow-up exam.)

Genetic Syndromes and Rare Diseases

  • For patients with Fibromuscular dysplasia (FMD):27
    • One-time vascular study from brain to pelvis
  • Vascular Ehlers-Danlos syndrome:28
    • At diagnosis and then every 18 months
    • More frequently if abnormalities are found
  • Loeys-Dietz:29
    • At diagnosis and then every two years
    • More frequently if abnormalities are found
  • Takayasu's Arteritis:17
    • For evaluation at diagnosis then as clinically indicated
  • Spontaneous coronary arteries dissection (SCAD)30
    • One-time vascular study from brain to pelvis
  • For other syndromes and rare diseases not otherwise addressed in the guideline, coverage is based on a case-by-case basis using societal guidance

Combination Studies
Brain CT and/or Brain CTA and/or Neck CTA

  • Recent stroke or transient ischemic attack (TIA)
  • Suspected carotid or vertebral artery dissection with focal or lateralizing neurological deficits
  • Approved vascular indications as noted above being performed in high-risk populations (in whom MRI is contraindicated or cannot be performed), will need anesthesia for the procedure and there is a suspicion of concurrent intracranial pathology

Note: MRA and CTA are generally comparable noninvasive imaging alternatives each with their own advantages and disadvantages. Brain MRI can alternatively be combined with Brain CTA/Neck CTA.

Brain CTA and/or Neck CTA

  • Recent ischemic stroke or transient ischemic attack31,32
    • Note: For remote strokes with no prior vascular imaging, imaging can be considered based on location/type of stroke and documented potential to change management
  • Known or suspected vertebrobasilar insufficiency (VBI) in patients with symptoms such as dizziness, vertigo, headaches, diplopia, blindness, vomiting, ataxia, weakness in both sides of the body, or abnormal speech4,5
  • Suspected carotid or vertebral artery dissection; due to trauma or spontaneous due to weakness of vessel wall19,20
  • Follow-up of known carotid or vertebral artery dissection within 3 – 6 months for evaluation of recanalization and/or to guide anticoagulation treatment21,22
  • Horner’s syndrome, non-central (miosis, ptosis, and anhidrosis)24
  • Large vessel vasculitis (Giant cell or Takayasu arteritis) with suspected intracranial and extracranial involvement
  • Follow-up of known carotid or vertebral artery dissection within 3 – 6 months for evaluation of recanalization and/or to guide anticoagulation treatment21,22
  • Asymptomatic patients with an abnormal ultrasound of the neck or carotid duplex imaging (e.g., carotid stenosis ≥ 70%, technically limited study, aberrant direction of flow in the carotid or vertebral arteries) and patient is surgery or angioplasty candidate7,8,9
  • Symptomatic patients with an abnormal ultrasound of the neck or carotid duplex imaging (e.g., carotid stenosis ≥ 50%, technically limited study, aberrant direction of flow in the carotid or vertebral arteries) and patient is surgery or angioplasty candidate7,10,11
  • Pulsatile tinnitus (subjective or objective) for suspected arterial vascular etiology26
  • Large vessel vasculitis (Giant cell or Takayasu arteritis) with suspected intracranial and extracranial involvement

Brain/Neck/Chest/Abdomen and Pelvis CTA

  • For patients with fibromuscular dysplasia (FMD), a one-time vascular study from brain to pelvis27,33
  • Vascular Ehlers-Danlos syndrome: At diagnosis and then every 18 months; more frequently if abnormalities are found28,34
  • Loeys-Dietz: at diagnosis and then every two years, more frequently if abnormalities are found29
  • For assessment in patients with spontaneous coronary artery dissection (SCAD), can be done at time of coronary angiography35


Neck/Chest/Abdomen/Pelvis CTA

  • Takayasu's Arteritis: For evaluation at diagnosis then as clinically indicated17

Rationale
MRA and CTA are generally comparable noninvasive imaging alternatives, each with their own advantages and disadvantages. CTA is quicker in the acute setting and MRA is an excellent screening test since it does not utilize ionizing radiation36

MRA vs CTA for Carotid Artery Evaluation (37,38)
Duplex ultrasound and contrast-MRA is a common choice for carotid artery evaluation. Limitations of MRA include difficulty in patients with claustrophobia and the risk of nephrogenic systemic sclerosis with gadolinium contrast agents in specific patients.

Advantages of CTA over MRA include superior spatial resolution, rapid image acquisition, decreased susceptibility to motion artifacts and artifacts from calcification as well as being better able to evaluate slow flow and tandem lesions. However, CTA can also overestimate high-grade stenosis. Limitations of CTA include radiation exposure to the patient, necessity of IV contrast, and risk of contrast allergy and contrast nephropathy.

CTA and Dissection
Craniocervical dissections can be spontaneous or traumatic. Patients with blunt head or neck trauma who meet Denver Screening criteria should be assessed for cerebrovascular injury (although about 20% will not meet criteria). The criteria include: focal or lateralizing neurological deficits (not explained by head CT), infarct on head CT, face, basilar skull, or cervical spine fractures, cervical hematomas that are not expanding, Glasgow coma score less than 8 without CT findings, massive epistaxis, cervical bruit or thrill.19,39,40,41

Spontaneous dissection presents with headache, neck pain with neurological signs or symptoms. There is often minor trauma or precipitating factor (e.g., exercise, neck manipulation). Dissection is thought to occur due to weakness of the vessel wall, and there may be an underlying connective tissue disorder. Dissection of the extracranial vessels can extend intracranially and/or lead to thrombus, which can migrate into the intracranial circulation causing ischemia. Therefore, MRA of the head and neck is warranted.20,42,43

CTA and Recent Stroke or Transient Ischemic Attack

  • When revascularization therapy is not indicated or available in patients with an ischemic stroke or TIA, the focus of the work-up is on secondary prevention. Both stroke and TIA should have an evaluation for high-risk modifiable factors such as carotid stenosis atrial fibrillation as the cause of ischemic symptoms44. Diagnostic recommendations include neuroimaging evaluation as soon as possible, preferably with magnetic resonance imaging, including DWI; noninvasive imaging of the extracranial vessels should be performed, and noninvasive imaging of intracranial vessels is reasonable.45
  • Patients with a history of stroke and recent work-up with new signs or symptoms indicating progression or complications of the initial CVA should have repeat brain imaging as an initial study. Patients with remote or silent strokes discovered on imaging should be evaluated for high-risk modifiable risk factors based on the location and type of the presumed etiology of the brain injury.

Contraindications and Preferred Studies

  • Contraindications and reasons why a CT/CTA cannot be performed may include: impaired renal function, significant allergy to IV contrast, pregnancy (depending on trimester).
  • Contraindications and reasons why an MRI/MRA cannot be performed may include: impaired renal function, claustrophobia, non-MRI compatible devices (such as non- compatible defibrillator or pacemaker), metallic fragments in a high-risk location, patient exceeds weight limit/dimensions of MRI machine.

References

  1. Robertson R L, Palasis S, Rivkin M J, Pruthi S, Bartel T B et al. ACR Appropriateness Criteria; Cerebrovascular Disease-Child. Journal of the American College of Radiology. 2020; 17: S36 - S54. 10.1016/j.jacr.2020.01.036.
  2. Salmela M B, Mortazavi S, Jagadeesan B D, Broderick D F, Burns J et al. ACR Appropriateness Criteria® Cerebrovascular Disease. Journal of the American College of Radiology. 2017; 14: S34 - S61. https://doi.org/10.1016/j.jacr.2017.01.051.
  3. Pannell J S, Corey A S, Shih R Y, Austin M J, Chu S et al. American College of Radiology. ACR Appropriateness Criteria® Cerebrovascular Diseases-Stroke and Stroke-Related Conditions. 2023.
  4. Lima Neto A, Roseli B, Gattas G S, Bor-Seng-Shu E, Oliveira M et al. Pathophysiology and Diagnosis of Vertebrobasilar Insufficiency: A Review of the Literature. International Archives of Otorhinolaryngology. 2017; 21: 302 - 307. 10.1055/s-0036-1593448.
  5. Searls D E, Pazdera L, Korbel E, Vysata O, Caplan L R. Symptoms and Signs of Posterior Circulation Ischemia in the New England Medical Center Posterior Circulation Registry. Arch Neurol. 2012; 69: 346 - 351. 10.1001/archneurol.2011.2083.
  6. American College of Radiology. ACR–ASNR–SPR PRACTICE PARAMETER FOR THE PERFORMANCE AND INTERPRETATION OF CERVICOCEREBRAL COMPUTED TOMOGRAPHY ANGIOGRAPHY (CTA). 2020.
  7. Brott T G, Halperin J L, Abbara S, Bacharach J M, Barr J D et al. 2011 ASA/ACCF/AHA/AANN/AANS/ACR/ASNR/CNS/SAIP/SCAI/SIR/SNIS/SVM/SVS Guideline on the Management of Patients With Extracranial Carotid and Vertebral Artery Disease. Circulation. 2011; 124: e54 - e130. 10.1161/CIR.0b013e31820d8c98.
  8. DaCosta M, Tadi P, Suroweic S. Carotid Endarterectomy. StatPearls Publishing Updated July 25, 2022. Accessed January 29, 2023. https://www.ncbi.nlm.nih.gov/books/NBK470582/.
  9. Marquardt L, Geraghty O C, Mehta Z, Rothwell P M. Low Risk of Ipsilateral Stroke in Patients With Asymptomatic Carotid Stenosis on Best Medical Treatment. Stroke. 2010; 41: e11 - e17. 10.1161/STROKEAHA.109.561837.
  10. Chaturvedi S, Bruno A, Feasby T, Holloway R, Benavente O et al. Carotid endarterectomy--an evidence-based review: report of the Therapeutics and. Neurology. 2005; 65: 794-801. doi: 10.1212/01.wnl.0000176036.07558.82.
  11. Rerkasem K, Rothwell P. Carotid endarterectomy for symptomatic carotid stenosis. The Cochrane database of systematic reviews. 2011; CD001081.
  12. Aulino J M, Kirsch C F, Burns J, Busse P M, Chakraborty S et al. ACR Appropriateness Criteria Neck Mass-Adenopathy. Journal of the American College of Radiology. 2019; 16: S150 - S160. 10.1016/j.jacr.2019.02.025.
  13. Nguyen R, Shah L, Quigley E, Harnsberger H, Wiggins R. Carotid Body Detection on CT Angiography. American Journal of Neuroradiology. 2011; 32: 1096–1099. 10.3174/ajnr.A2429.
  14. Aghayev A, Steigner M L, Azene E M, Burns J, Chareonthaitawee P et al. ACR Appropriateness Criteria; Noncerebral Vasculitis. Journal of the American College of Radiology. 2021; 18: S380 - S393. 10.1016/j.jacr.2021.08.005.
  15. Halbach C, McClelland C M, Chen J, Li S, Lee M S. Use of Noninvasive Imaging in Giant Cell Arteritis. Asia-Pacific Journal of Ophthalmology. 2018; 7: 260 - 264. https://doi.org/10.22608/APO.2018133.
  1. Koster M J, Matteson E L, Warrington K J. Large-vessel giant cell arteritis: diagnosis, monitoring and management. Rheumatology (Oxford). 2018; 57: ii32 - ii42. 10.1093/rheumatology/kex424.
  2. Maz M, Chung S A, Abril A, Langford C A, Gorelik M et al. 2021 American College of Rheumatology/Vasculitis Foundation Guideline for the Management of Giant Cell Arteritis and Takayasu Arteritis. Arthritis Rheumatol. 2021; 73: 1349 - 1365. https://doi.org/10.1002/art.41774.
  3. Rafailidis V, Li X, Chryssogonidis I, Rengier F, Rajiah P et al. Multimodality Imaging and Endovascular Treatment Options of Subclavian Steal Syndrome. Canadian Association of Radiologists Journal. 2018; 69: 493 - 507. https://doi.org/10.1016/j.carj.2018.08.003.
  4. Franz R W, Willette P A, Wood M J, Wright M L, Hartman J F. A Systematic Review and Meta- Analysis of Diagnostic Screening Criteria for Blunt Cerebrovascular Injuries. Journal of the American College of Surgeons. 2012; 214: doi:10.1016/j.jamcollsurg.2011.11.012.
  5. Shakir H J, Davies J M, Shallwani H, Siddiqui A H, Levy E I. Carotid and Vertebral Dissection Imaging. Current Pain and Headache Reports. 2016; 20. 10.1007/s11916-016-0593-5.
  6. Patel S, Haynes R, Staff I, Tunguturi A, Elmoursi D. Recanalization of cervicocephalic artery dissection. Brain circulation. 2020; 6: 175-180. doi:10.4103/bc.bc_19_20.
  7. Larsson S, King A, Madigan J, Levi C, Norris J. Prognosis of carotid dissecting aneurysms: Results from CADISS and a systematic review. Neurology. 2017; 88: 646-652. doi:10.1212/wnl.0000000000003617.
  8. Travis Caton M, Miskin N, Guenette J P. The role of computed tomography angiography as initial imaging tool for acute hemorrhage in the head and neck. Emergency Radiology. 2021; 28: 215 - 221. 10.1007/s10140-020-01835-9.
  9. Kim J, Hashemi N, Gelman R, Lee A. Neuroimaging in ophthalmology. Saudi journal of ophthalmology: official journal of the Saudi Ophthalmological. 2012; 26: 401-7. doi:10.1016/j.sjopt.2012.07.001.
  10. Davagnanam I, Fraser C, Miszkiel K, Daniel C, Plant G. Adult Horner’s syndrome: a combined

clinical, pharmacological, and imaging algorithm. Eye. 2013; 27: 291 - 298. 10.1038/eye.2012.281.

  1. Pegge S, Steens S, Kunst H, Meijer F. Pulsatile Tinnitus: Differential Diagnosis and Radiological Work-Up. Current radiology reports. 2017; 5: 5. doi:10.1007/s40134-017-0199-7.
  2. Gornik H L, Persu A, Adlam D, Aparicio L S, Azizi M et al. First International Consensus on the diagnosis and management of fibromuscular dysplasia. Vascular Medicine. 2019; 24: 164 - 189. 10.1177/1358863X18821816.
  3. Byers P. Vascular Ehlers-Danlos Syndrome. 1999 Sep 2 [Updated 2019 Feb 21]. GeneReviews® [Internet]. 2019.
  4. Loeys B, Dietz H. Loeys-Dietz Syndrome. 2008 Feb 28 [Updated 2018 Mar 1]. GeneReviews® [Internet]. 2018.
  5. Hayes S N, Kim E S, Saw J, Adlam D, Arslanian-Engoren C et al. Spontaneous Coronary Artery Dissection: Current State of the Science: A Scientific Statement From the American Heart Association. Circulation. 2018; 137: e523 - e557. 10.1161/CIR.0000000000000564.
  6. Kleindorfer D, Towfighi A, Chaturvedi S, Cockroft K, Gutierrez J et al. 2021 Guideline for the Prevention of Stroke in Patients With Stroke and Transient Ischemic Attack: A Guideline From the American Heart Association/American Stroke Association. Stroke. 2021; 52: e364-e467. 10.1161/STR.0000000000000375.
  7. Pannell J, Corey A, Shih R , Austin M, Chu S et al. ACR Appropriateness Criteria® Cerebrovascular Diseases-Stroke and Stroke-Related Conditions. J Am Coll Radiol. 2023.
  1. Kesav P, Manesh Raj D, John S. Cerebrovascular Fibromuscular Dysplasia - A Practical Review. Vascular health and risk management. 2023; 19: 543-556. 10.2147/VHRM.S388257.
  2. Bowen J, Hernandez M, Johnson D, Green C, Kammin T et al. Diagnosis and management of vascular Ehlers-Danlos syndrome: Experience of the UK national diagnostic service, Sheffield. European journal of human genetics. 2023; 31: 749-760. 10.1038/s41431-023-01343-7.
  3. Teruzzi G, Santagostino Baldi G, Gili S, Guarnieri G, Montorsi P. Spontaneous Coronary Artery Dissections: A Systematic Review. Journal of clinical medicine. 2021; 10: 10.3390/jcm10245925.
  4. American College of Radiology. ACR–ASNR–SNIS–SPR PRACTICE PARAMETER FOR THE PERFORMANCE OF CERVICOCEREBRAL MAGNETIC RESONANCE ANGIOGRAPHY (MRA). Updated 2020. Accessed May 6, 2024.
  5. American College of Radiology. ACR Appropriateness Criteria® Cerebrovascular Disease. American College of Radiology (ACR). Updated 2016. Accessed February 8, 2023. https://acsearch.acr.org/docs/69478/Narrative/.
  6. American College of Radiology. ACR Appropriateness Criteria® Cerebrovascular Diseases- Aneurysm, Vascular Malformation, and Subarachnoid Hemorrhage. American College of Radiology (ACR). Updated 2021. Accessed February 8, 2023. https://acsearch.acr.org/docs/3149013/Narrative/.
  7. Liang T, Tso D K, Chiu R Y W, Nicolaou S. Imaging of Blunt Vascular Neck Injuries: A Review of Screening and Imaging Modalities. American Journal of Roentgenology. 2013; 201: 884 - 892. 10.2214/AJR.12.9664.
  8. Mundinger G S, Dorafshar A H, Gilson M M, Mithani S K, Manson P N. Blunt-Mechanism Facial Fracture Patterns Associated With Internal Carotid Artery Injuries: Recommendations for Additional Screening Criteria Based on Analysis of 4,398 Patients. Journal of Oral and Maxillofacial Surgery. 2013; 71: 2092 - 2100. 10.1016/j.joms.2013.07.005.
  9. Simon L V, Nassar A K, Mohseni M. Vertebral Artery Injury. StatPearls Publishing Updated July 18, 2022. Accessed January 29, 2023. https://www.ncbi.nlm.nih.gov/books/NBK470363/.
  10. Nash M, Rafay M F. Craniocervical Arterial Dissection in Children: Pathophysiology and Management. Pediatric Neurology. 2019; 95: 9 - 18. 10.1016/j.pediatrneurol.2019.01.020.
  11. Clark M, Unnam S, Ghosh S. A review of carotid and vertebral artery dissection. British Journal of Hospital Medicine. 2022; 83: 1 - 11. 10.12968/hmed.2021.0421.
  12. Kernan W, Ovbiagele B, Black H, Bravata D, Chimowitz M et al. Guidelines for the prevention of stroke in patients with stroke and transient ischemic attack: a guideline for healthcare professionals from the American Heart Association/American Stroke Association. Stroke. 2014; 45: 2160-236. 10.1161/STR.0000000000000024.
  13. Wintermark M, Sanelli P, Albers G, Bello J, Derdeyn C et al. Imaging recommendations for acute stroke and transient ischemic attack patients: A joint statement by the American Society of Neuroradiology, the American College of Radiology, and the Society of NeuroInterventional Surgery. AJNR Am J Neuroradiol. 2013; 34: E117-27. 10.3174/ajnr.A3690.

Coding Section

Codes Number Description
CPT 70498

Computed tomographic angiography, neck, with contrast material(s), including noncontrast images, if performed, and image postprocessing.

Procedure and diagnosis codes on Medical Policy documents are included only as a general reference tool for each policy. They may not be all-inclusive. 

This medical policy was developed through consideration of peer-reviewed medical literature generally recognized by the relevant medical community, U.S. FDA approval status, nationally accepted standards of medical practice and accepted standards of medical practice in this community, and other nonaffiliated technology evaluation centers, reference to federal regulations, other plan medical policies, and accredited national guidelines.

"Current Procedural Terminology © American Medical Association. All Rights Reserved" 

History From 2019 Forward     

11/01/2024 Annual review, updating policy for clarity and consistency, also adding: Follow-up of known carotid or vertebral artery dissection within 3-6 months for evaluation of recanalization and/or to guide anticoagulation treatment (already in combo – Homer’s syndrome, non-central (miosis, ptosis, and anhidrosis) – also in combo section - Giant cell arteritis with suspected intracranial and extracranial involvement -  also in combo section – Genetic syndromes and rare disease section. Also adding purpose, background and contraindications/preferred studies sections. Updating references.
11/21/2023 Annual review, entire policy updated for consistency. Adding verbiage for congenital vascular malformations of head and neck, follow up known carotid or vertebral atery dissection and indeterminate findings on prior imaging.
11/16/2022 Annual review, no change to policy intent. Updating policy for clarity.
11/01/2021  Annual review, adding medical necessity criteria for Loeys-Dietz syndrome, vertebrobasilar insufficiency, pulsatile mass and pulsatile tinnitus. Also updating background and references. 
11/01/2020  Annual review, numerous clarifications and additions made to policy statement, also updating references and background. 
11/14/2019               NEW POLICY
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