TEMPORAL BONE, MASTOID, ORBITS CT - CAM 745

Description
Computed tomography’s use of thin sections with multi-planar reconstruction (e.g., axial, coronal, and sagittal planes), along with its three-dimensional rendering, permits thorough diagnosis and management of ocular and orbital disorders. Brain CT is often ordered along with CT of the orbit for head injury with orbital trauma. MRI Orbits is preferred over CT Orbits except in the case of orbital trauma, infection, or bone abnormalities.

Temporal bone, mastoid, and internal auditory canal computed tomography (CT) is a unique study performed for problems, such as conductive hearing loss, chronic otitis media, mastoiditis, cholesteatoma, congenital hearing loss and cochlear implants. It is a modality of choice because it provides 3D positional information and offers a high degree of anatomic detail. It is rarely used for evaluation of VIIth or VIIIth nerve tumors.

Policy
CT is preferred for visualizing bony detail and calcifications., MRI is superior for the evaluation of the visual pathways, globe, and soft tissues is considered MEDICALLY NECESSARY for the following indications:

  • Abnormal external or direct eye exam (Hande, 2012):
    • Exophthalmos (proptosis) or enophthalmos
    • Ophthalmoplegia with concern for orbital pathology (Stalcup, 2013)
    • Unilateral optic disk swelling if MRI is contraindicated or cannot be performed (Hata, 2017; Margolin, 2019; Passi, 2013)
    • Documented visual defect if MRI is contraindicated or cannot be performed (Fadzil, 2013; Kedar, 2011; Prasad, 2012; Sadun, 2011)
      • Unilateral or with abnormal optic disc(s) (i.e., optic disc blurring, edema, or pallor); AND
      • Not explained by an underlying diagnosis, glaucoma, or macular degeneration
  • Optic Neuritis if MRI is contraindicated or cannot be performed
    • With an atypical presentation, severe visual impairment or poor recovery following initial onset or treatment onset (CMSC, 2018; Voss, 2011)
    • If needed to confirm optic neuritis and rule out compressive lesions
  • Orbital trauma
    • Physical findings of direct eye injury
    • Suspected orbital trauma with indeterminate x-ray
    • For further evaluation of a fracture seen on x-ray for treatment or surgical planning
  • Orbital or ocular mass/tumor, suspected, or known (Hande, 2012; Kedar, 2011)
  • Clinical suspicion of orbital infection (Gavito-Higuera, 2016; Kirsch, 2017)
  • Clinical suspicion of osteomyelitis (Arunkumar, 2011; Lee, 2016)
    • Direct visualization of bony deformity OR
    • Abnormal x-rays
  • Clinical suspicion of Orbital Inflammatory Disease (e.g., eye pain and restricted eye movement with suspected orbital pseudotumor) (Pakdaman, 2014)
  • Congenital orbital anomalies (Tawfik, 2012)
  • Complex strabismus to aid in diagnosis, treatment and/or surgical planning (Demer; 2002; Kadom, 2008)

Combination Studies with Orbit CT

  • Brain CT/Orbit CT if MRI is contraindicated or cannot be performed
    • Optic neuropathy or unilateral optic disk swelling of unclear etiology to distinguish between a compressive lesion of the optic nerve, optic neuritis, ischemic optic neuropathy (arteritic or non-arteritic), central retinal vein occlusion, or optic nerve infiltrative disorders (Behbehani, 2007)
    • Bilateral optic disk swelling (papilledema) with vision loss (Margolin, 2019)
    • Approved indications as noted above and being performed in high-risk populations and will need anesthesia for the procedure and there is a suspicion of concurrent intracranial pathology (Lawson, 2000)

INDICATIONS FOR SELLA CT

MRI is contraindicated or cannot be performed (ACR NE, 2018; Chaudhary, 2011) 

  • For further evaluation of known sellar and parasellar masses
  • Suspected pituitary gland disorder (Wu, 2014) based on:
    • Documented visual field defect suggesting compression of the optic chiasm; OR
    • Laboratory findings suggesting pituitary dysfunction (Freda, 2011); OR
    • Pituitary apoplexy with sudden onset of neurological and hormonal symptoms
    • Follow-up to other imaging suggesting sella (pituitary) mass

INDICATIONS FOR TEMPORAL/MASTOID/INTERNAL AUDITORY CANAL CT

Hearing loss (documented on audiogram) (Cunnane, 2019; Sharma, 2018) 

  • Asymmetric sensorineural when MRI is contraindicated (Krause, 2010; Verbist, 2012)
  • Conductive or mixed (Trojanowska, 2012)
  • Congenital (Trojanowska, 2012)
  • Cochlear implant evaluation (Juliano, 2015)

Tinnitus (Kessler, 2017; Pegge, 2017; Yew, 2014) 

  • Pulsatile tinnitus
  • Unilateral non-pulsatile tinnitus and MRI is contraindicated or cannot be performed

Ear Infection  

  • Clinical suspicion of acute mastoiditis as a complication of acute otitis media (Kann, 2016; Luntz, 2012; Patel, 2014; Platzek, 2014)
    • Systemic illness or toxic appearance
    • Signs of extracranial complications (e.g., postauricular swelling/erythema, auricular protrusion, retro-orbital pain, hearing loss, tinnitus, vertigo, nystagmus)
    • Not responding to treatment

Note: MRI is also indicated if there are signs of intracranial complications (e.g., meningeal signs, cranial nerve deficits, focal neurological findings, altered mental status).

This is most common in the pediatric population

  • Chronic Otitis Media (with or without cholesteatoma on exam) (Gomaa, 2013; Patel, 2014)
    • Failed treatment for acute otitis media

Cholesteatoma (Barath, 2011; Chen, 2018)

CSF Otorrhea (Hiremath, 2019; Vemuri, 2017) 

  • When looking to characterize a bony defect (for intermittent leaks and complex cases consider CT/MR/Nuclear Cisternography). CSF fluid should always be confirmed with laboratory testing (Beta-2 transferrin assay.)

Temporal Bone Fracture (Collins, 2012; Kennedy, 2014; Lantos, 2019) 

  • Suspected based on mechanism of injury OR
  • Indeterminate findings on initial imaging OR
  • For further evaluation of a known fracture for treatment or surgical planning

Vascular Indications (Bozek, 2016; Muderris, 2011) 

  • Suspected or known with need for further evaluation
    • Dehiscence of the jugular bulb or carotid canal OR
    • Other vascular anomalies of the temporal bone (i.e., aberrant internal carotid artery, high jugular bulb, persistent stapedial artery, aberrant petrosal sinus)

Peripheral vertigo (Muncie, 2017; Sharma, 2018; Strupp, 2013) 

  • Based on clinical exam (Head-Impulse with saccade, Spontaneous unidirectional horizontal nystagmus, Dix-Hallpike maneuver); AND 
    • Persistent symptoms after a trial of medication and four weeks of vestibular therapy (e.g., Epley’s maneuvers)

Bell’s Palsy/hemifacial spasm if MRI is contraindicated or cannot be performed (for evaluation of the extracranial nerve course) 

  • If atypical signs, slow resolution beyond three weeks, no improvement at four months, or facial twitching/spasms prior to onset (Quesnel, 2010)

OTHER INDICATIONS FOR TEMPORAL BONE, MASTOID, ORBITS, SELLA, INTERNAL AUDITORY CANAL CT

Pre-operative/procedural evaluation 

  • Pre-operative evaluation for a planned surgery or procedure

Post- operative/procedural evaluation 

  • When imaging, physical, or laboratory findings indicate surgical or procedural complications
  • 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.

All other uses of this technology are investigational and/or unproven and therefore considered NOT MEDICALLY NECESSARY. 

References  

  1. Abuabara A. Cerebrospinal fluid rhinorrhoea: diagnosis and management. Med Oral Patol Oral Cir Bucal. 2007;12(5):E397-400.
  2. American College of Radiology ACR Appropriateness Criteria® - Neuroendocrine Imaging. 2018. https://acsearch.acr.org/docs/69485/Narrative/.
  3. Arunkumar JS, Naik AS, Prasad KC, et al. Role of nasal endoscopy in chronic osteomyelitis of maxilla and zygoma: A case report. Case Reports in Medicine. 2011; Article ID 802964.
  4. Baráth K, Huber AM, Stämpfli P, Varga Z, Kollias S. Neuroradiology of cholesteatomas. AJNR Am J Neuroradiol. 2011;32(2):221-229. doi:10.3174/ajnr.A2052.
  5. Behbehani R. Clinical approach to optic neuropathies. Clin Ophthalmol. 2007; 1(3):233-246.
  6. Bożek P, Kluczewska E, Misiołek M, et al. The prevalence of persistent petrosquamosal sinus and other temporal bone anatomical variations on high-resolution temporal bone computed tomography. Med Sci Monit. 2016; 22:4177-4185. http://doi.org/10.12659/MSM.898546. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5108369/.
  7. Chaudhary V, Bano S. Imaging of the pituitary: Recent advances. Indian J Endocrinol Metab. 2011; 15 Suppl 3(Suppl3):S216-S223. doi:10.4103/2230-8210.84871
  8. Chen Y, Li P. Application of high resolution computer tomography in external ear canal cholesteatoma diagnosis. J Otol. 2018;13(1):25-28. doi:10.1016/j.joto.2017.10.004.
  9. Collins JM, Krishnamoorthy AK, Kubal WS, Johnson MH, Poon CS. Multidetector CT of temporal bone fractures. Semin Ultrasound CT MR. 2012;33(5):418-431. doi:10.1053/j.sult.2012.06.006
  10. Consortium of Multiple Sclerosis Centers (CMSC). MRI Protocol and Clinical Guidelines for the Diagnosis and Follow-up of MS. February 2018.
  11. Cunnane MB. Imaging of tinnitus. Neuroimaging Clinics. 2019 Feb; 29(1):49-56.
  12. Demer JL, Clark RA, Kono R, Wright W, Velez F, Rosenbaum AL. A 12-year, prospective study of extraocular muscle imaging in complex strabismus. J AAPOS. 2002;6(6):337-347. doi:10.1067/mpa.2002.129040.
  13. Fadzil F, Ramli N, Ramli NM. MRI of optic tract lesions: review and correlation with visual field defects. Clin Radiol. 2013 Oct; 68(10):e538-51.
  14. Freda PU, Beckers AM, Katznelson L, et al. Pituitary incidentaloma: An endocrine society clinical practice guideline. J Clin Endocrinol Metab. 2011 Apr; 96(4):894-904.
  15. Gala F. Magnetic resonance imaging of optic nerve. Indian J Radiol Imaging. 2015;25(4):421- 438. doi:10.4103/0971-3026.169462
  16. Gavito-Higuera J, Mullins CB, Ramos-Duran L, et al. Sinonasal fungal infections and complications: A pictorial review. J Clin Imaging Sci. 2016 Jun 14; 6:23.
  17. Gomaa MA, Rahim A, Karim AA, et al. Evaluation of temporal bone cholesteatoma and the correlation between high resolution computed tomography and surgical finding. Clin MedInsights Ear Nose Throat. 2013; 6: 21-28.
  18. Hande PC, Talwar I. Multimodality imaging of the orbit. Indian J Radiol Imaging. 2012; 22(3):227-239. http://doi.org/10.4103/0971-3026.107184.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3624745/.
  19. Hata M, Miyamoto K. Causes and prognosis of unilateral and bilateral optic disc swelling Neuroophthalmology. 2017 Aug; 41(4):187-191. 
  20. Hiremath SB, Gautam AA, Sasindran V, et al. Cerebrospinal fluid rhinorrhea and otorrhea: A multimodality imaging approach. Diagn Interven Imaging. 2019 Jan; 100(1):3-15. https://doi.org/10.1016/j.diii.2018.05.003.
  21. Juliano AF, Ginat DT, Moonis G. Imaging review of the temporal bone: Part II. Traumatic, postoperative, and noninflammatory nonneoplastic conditions. Radiology. 2015. 276(3).
  22. Kadom N. Pediatric strabismus imaging. Current Opinion in Ophthalmology. 2008;19(5):371- 378. doi:10.1097/ICU.0b013e328309f165.
  23. Kann K. Acute mastoiditis: Pearls and pitfalls. emDocs website. 2016 Mar 27. http://www.emdocs.net/acute-mastoiditis-pearls-and-pitfalls/.
  24. Kanda T, Miyazaki A, Zeng F, et al. Magnetic resonance imaging of intraocular optic nerve disorders: review article. pjr. 2020;85(1):67-81. doi:10.5114/pjr.2020.93364.
  25. Kedar S, Ghate D, Corbett JJ. Visual fields in neuro-ophthalmology. Indian J Ophthalmol. 2011 Mar-Apr; 59(2):103-109.
  26. Kennedy TA, Avey GD, Gentry LR. Imaging of temporal bone trauma. Neuroimaging Clin N Am. 2014;24(3):467-486, viii. doi:10.1016/j.nic.2014.03.003.
  27. Kennedy TA, Corey AS, Policeni B, et al. American College of Radiology (ACR) Appropriateness Criteria. Expert Panel on Neurologic Imaging: Orbits, Vision and Visual Loss. https://acsearch.acr.org/docs/69486/Narrative/. Published 2018.
  28. Kessler MM, Moussa M, Bykowski J, et al. Expert Panel on Neurologic Imaging. American College of Radiology (ACR) Appropriateness Criteria: Tinnitus. https://acsearch.acr.org/docs/3094199/Narrative/. Published 2017.
  29. Kirsch CFE, Bykowski J, et al. ACR Appropriateness Criteria - Sinonasal Disease. J Am Coll Radiol. 2017 Nov; 14(11S):S550-S559.
  30. Krause N, Fink KT, Fink JR. Asymmetric sensorineural hearing loss caused by vestibular schwannoma: Characteristic imaging features before and after treatment with stereotactic radiosurgery. Radiol Case Rep. 2010; 5(2):437.
  31. Lantos JE, Leeman K, Weidman EK, Dean KE, Peng T, Pearlman AN. Imaging of temporal bone trauma: A clinicoradiologic perspective. Neuroimaging Clin N Am. 2019;29(1):129-143. doi:10.1016/j.nic.2018.08.005.
  32. Lawson, GR. Sedation of children for magnetic resonance imaging. Archives Dis Childhood. 2000; 82(2).
  33. Lee YJ, Sadigh S, Mankad K, et al. The imaging of osteomyelitis. Quant Imaging Med Surg. 2016; 6(2):184-198. http://doi.org/10.21037/qims.2016.04.01 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4858469/.
  34. Luntz M, Bartal K, Brodsky A, et al. Acute mastoiditis: The role of imaging for identifying intracranial complications. Laryngoscope. 2012 Dec; 122(12):2813-7. https://doi.org/10.1002/lary.22193.
  35. Mantur M, Łukaszewicz-Zając M, Mroczko B, et al. Cerebrospinal fluid leakage—Reliable diagnostic methods. Clinica Chimica Acta. 2011;412(11-12):837-840. doi:10.1016/j.cca.2011.02.017
  36. Margolin E. Swollen optic nerve: An approach to diagnosis and management. Pract Neurol. 2019 Jun 13. Epub ahead of print.
  37. Muderris T, Bercin S, Sevil E, et al. A potentially catastrophic anatomical variation: Aberrant internal carotid artery in the middle ear cavity. Case Rep Otolaryngol. 2013; 2013:743021. https://doi.org/10.1155/2013/743021.
  38. Muncie H. Dizziness: Approach to evaluation and management. Am Fam Physician. February 1, 2017; 95(3):154-162. https://www.aafp.org/afp/2017/0201/p154.html.
  39. Othman BA, FitzGibbon EJ, Wendt S. Optic Atrophy. EyeWiki. Published December 29, 2020. Accessed July 2, 2021. https://eyewiki.aao.org/Optic_Atrophy
  40. Pakdaman MN, Sepahdari AR, Elkhamary SM. Orbital inflammatory disease:
  41. Pictorial review and differential diagnosis. World J Radiol. 2014 Apr 28; 6(4):106-15. doi: 10.4329/wjr.v6.i4.106.
  42. Passi N, Degnan AJ, Levy LM. MR imaging of papilledema and visual pathways: Effects of increased intracranial pressure and pathophysiologic mechanisms. Am J Neuroradiol. 2013 May; 34(5):919-924.
  43. Patel KM, Almutairi A, Mafee MF. Acute otomastoiditis and its complications: Role of imaging. Operative Techniques in Otolaryngology. 2014; 25:21-28.
  44. Pegge SAH, Steens SCA, Kunst HPM et. Al. Pulsatile Tinnitus: Differential Diagnosis and Radiological Work-Up. Curr Radiol Rep. 2017; 5(1):5
  45. Platzek I, Kitzler HH, Gudziol V, et al. Magnetic resonance imaging in acute mastoiditis. ActaRadiol Short Rep. 2014 Feb; 3(2):2047981614523415.
  46. Prasad S, Galetta SL. Approach to the patient with acute monocular visual loss. Neurol Clin Pract. 2012; 2(1):14-23.
  47. Quesnel AM, Lindsay RW, Hadlock TA. When the bell tolls on Bell's palsy: Finding occult malignancy in acute-onset facial paralysis. Am J Otolaryngol. 2010 Sep-Oct; 31(5):339-42. Epub 2009 Jun 24.
  48. Sadun AA, Wang MY. Abnormalities of the optic disc. Handb Clin Neurol. 2011; 102:117-57. doi: 10.1016/B978-0-444-52903-9.00011-X.
  49. Sharma A, Kirsch CF, Aulino JM, et al. Expert Panel on Neurologic Imaging. American College of Radiology (ACR) Appropriateness Criteria: Hearing Loss and/or Vertigo. https://acsearch.acr.org/docs/69488/Narrative. Published 2018.
  50. Stalcup ST, Tuan AS, Hesselink JR. Intracranial causes of ophthalmoplegia: The visual reflex pathways. RadioGraphics. 2013; 33(5).
  51. Strupp M, Dieterich M, Brandt T. The treatment and natural course of peripheral and central vertigo. Dtsch Arztebl Int. 2013 Jul; 110(29-30):505–16.
  52. Tawfik HA, Abdelhalim A, Elkafrawy MH. Computed tomography of the orbit - A review and an update. Saudi J Ophthalmol. 2012; 26(4):409-418. doi:10.1016/j.sjopt.2012.07.004
  53. Trojanowska A, Drop A, Trojanowski P, et. al. External and middle ear diseases: Radiological diagnosis based on clinical signs and symptoms. Insights Imaging. 2012 Feb; 3(1):33-48.
  54. Vemuri N, Karanam LP, Manchikanti V, Dandamudi S, Puvvada S, Vemuri V. Imaging review of cerebrospinal fluid leaks. Indian J Radiol Imaging. 2017;27(4):441. doi:10.4103/ijri.IJRI_380_16.
  55. Verbist BM. Imaging of sensorineural hearing loss: A pattern-based approach to diseases of the inner ear and cerebellopontine angle Insights Imaging. 2012 Apr; 3(2):139-153.
  56. Voss E, Raab P, Trebst C, et al. Clinical approach to optic neuritis: Pitfalls, red flags and differential diagnosis. Ther Adv Neurol Disord. 2011; 4(2):123-34. http://doi.org/10.1177/1756285611398702. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3105615/.
  57. Wu L, Li Y, Yin Y, et al. Usefulness of dual-energy computed tomography imaging in the differential diagnosis of sellar meningiomas and pituitary adenomas: Preliminary report. PLoS One. 2014 Mar; 9(3):e90658.
  58. Yew K. Diagnostic approach to patients with tinnitus. Am Fam Physician. January 15, 2014; 89(2):106-13. https://www.aafp.org/afp/2014/0115/p106.html.

Coding Section 

Code Number Description
CPT 70480
Computed tomography, orbit, sella, or posterior fossa or outer, middle, or inner ear; without contrast material
  70481 Computed tomography, orbit, sella, or posterior fossa or outer, middle, or inner ear; with contrast material(s)
  70482 Computed tomography, orbit, sella, or posterior fossa or outer, middle, or inner ear; without contrast material, followed by contrast material(s) and further sections

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, Blue Cross and Blue Shield Association technology assessment program (TEC) and other non-affiliated 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     

12/08/2021 

Annual review, adding policy verbiage related to complex strabismus, temporal bone fracture, optic neuritis, visual defect, osteomyelitis, optic neuropathy and csf otorrhea. Also updating description and references. 

11/10/2020 

Annual review, clarifying policy verbiage and updating references and description. 

12/03/2019

New Policy

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