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.

Policy
INDICATIONS FOR ORBIT CT

Note: CT is preferred for visualizing bony detail and calcifications. MRI is superior for the evaluation of the visual pathways, globe, and soft tissues.^{1, 2}

• Abnormal external or direct eye exam¹:
  • Exophthalmos (proptosis) or enophthalmos o Ophthalmoplegia with concern for orbital pathology³
  • Unilateral optic disk swelling if MRI is contraindicated or cannot be performed^4-6
  • Documented visual defect if MRI is contraindicated or cannot be performed^7-10
    • 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
  • If atypical presentation (bilateral, absence of pain, optic nerve hemorrhages, severe visual impairment, lack of response to steroids, poor recovery or recurrence)^11-14
  • 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^{1, 7}
• Clinical suspicion of orbital infection^{15, 16}
• Clinical suspicion of osteomyelitis^{17, 18}
  • 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) if MRI is contraindicated or cannot be performed¹⁹
• Congenital orbital anomalies²⁰
• Complex strabismus (with ophthalmoplegia or ophthalmoparesis) to aid in diagnosis, treatment and/or surgical planning^21-23

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 disorders²⁴
  • Bilateral optic disk swelling (papilledema) with vision loss⁵
  • 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 pathology²⁵

INDICATIONS FOR SELLA CT²⁶
When MRI is contraindicated or cannot be performed^{27, 28}

• For further evaluation of known sellar and parasellar masses
• Suspected pituitary gland disorder²⁹ based on any of the following:
  • Documented visual field defect suggesting compression of the optic chiasm; OR
  • Laboratory findings suggesting pituitary dysfunction³⁰; OR
  • Pituitary apoplexy with sudden onset of neurological and hormonal symptoms; OR
  • Other imaging suggesting sella (pituitary) mass

INDICATIONS FOR TEMPORAL/MASTOID/INTERNAL AUDITORY CANAL CT
Hearing loss (documented on audiogram)^{31, 32}

• Asymmetric sensorineural when MRI is contraindicated^{33, 34}
• Conductive or mixed³⁵
• Congenital³⁵
• Cochlear implant evaluation^36-39

Note: For congenital/childhood sensorineural hearing loss suspected to be due to a structural abnormality, CT is the preferred imaging modality for the osseous structures and malformations of the inner ear. MRI is used for evaluating CNVIII, the brain parenchyma, or the membranous labyrinth.

Tinnitus^40-42

• Pulsatile tinnitus with concern for osseous pathology of the temporal bone
• 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^43-46
  • 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)^{45, 47}
  • Failed treatment for acute otitis media

Cholesteatoma^{48, 49}

CSF Otorrhea^{50, 51}

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

Temporal Bone Fracture^52-54

• 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^{55, 56}

• 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^{32, 57, 58}

• 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 onset⁵⁹

OTHER INDICATIONS FOR TEMPORAL BONE, MASTOID, ORBIT, 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.

Further evaluation of indeterminate findings on prior imaging (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)

Rationale
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.

References  

1. Hande PC, Talwar I. Multimodality imaging of the orbit. Indian J Radiol Imaging. Jul 2012;22(3):227-39. doi:10.4103/0971-3026.107184
2. Kennedy TA, Corey AS, Policeni B, et al. ACR Appropriateness Criteria(®) Orbits Vision and Visual Loss. J Am Coll Radiol. May 2018;15(5s):S116-s131. doi:10.1016/j.jacr.2018.03.023
3. Stalcup ST, Tuan AS, Hesselink JR. Intracranial causes of ophthalmoplegia: the visual reflex pathways. Radiographics. Sep-Oct 2013;33(5):E153-69. doi:10.1148/rg.335125142
4. Hata M, Miyamoto K. Causes and Prognosis of Unilateral and Bilateral Optic Disc Swelling. Neuroophthalmology. Aug 2017;41(4):187-191. doi:10.1080/01658107.2017.1299766
5. Margolin E. The swollen optic nerve: an approach to diagnosis and management. Pract Neurol. Aug 2019;19(4):302-309. doi:10.1136/practneurol-2018-002057
6. Passi N, Degnan AJ, Levy LM. MR imaging of papilledema and visual pathways: effects of increased intracranial pressure and pathophysiologic mechanisms. AJNR Am J Neuroradiol. May 2013;34(5):919-24. doi:10.3174/ajnr.A3022
7. Kedar S, Ghate D, Corbett JJ. Visual fields in neuro-ophthalmology. Indian J Ophthalmol. Mar-Apr 2011;59(2):103-9. doi:10.4103/0301-4738.77013
8. Fadzli F, Ramli N, Ramli NM. MRI of optic tract lesions: review and correlation with visual field defects. Clin Radiol. Oct 2013;68(10):e538-51. doi:10.1016/j.crad.2013.05.104
9. Prasad S, Galetta SL. Approach to the patient with acute monocular visual loss. Neurol Clin Pract. Mar 2012;2(1):14-23. doi:10.1212/CPJ.0b013e31824cb084
10. 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
11. Kaur K, Gurnani B, Devy N. Atypical optic neuritis - a case with a new surprise every visit. GMS Ophthalmol Cases. 2020;10:Doc11. doi:10.3205/oc000138
12. Phuljhele S, Kedar S, Saxena R. Approach to optic neuritis: An update. Indian J Ophthalmol. Sep 2021;69(9):2266-2276. doi:10.4103/ijo.IJO_3415_20
13. Consortium of Multiple Sclerosis Centers. 2018 MRI Protocol and Clinical Guidelines for MS. Consortium of Multiple Sclerosis Centers (CMSC). Updated May 22, 2018. Accessed January 23, 2023. https://www.mscare.org/page/MRI_protocol
14. Voss E, Raab P, Trebst C, Stangel M. Clinical approach to optic neuritis: pitfalls, red flags and differential diagnosis. Ther Adv Neurol Disord. Mar 2011;4(2):123-34. doi:10.1177/1756285611398702
15. Gavito-Higuera J, Mullins CB, Ramos-Duran L, Sandoval H, Akle N, Figueroa R. Sinonasal Fungal Infections and Complications: A Pictorial Review. J Clin Imaging Sci. 2016;6:23. doi:10.4103/2156-7514.184010
16. American College of Radiology. ACR Appropriateness Criteria® Sinonasal Disease. American College of Radiology (ACR). Updated 2021. Accessed December 30, 2022. https://acsearch.acr.org/docs/69502/Narrative/
17. Arunkumar JS, Naik AS, Prasad KC, Santhosh SG. Role of nasal endoscopy in chronic osteomyelitis of maxilla and zygoma: a case report. Case Rep Med. 2011;2011:802964. doi:10.1155/2011/802964
18. Lee YJ, Sadigh S, Mankad K, Kapse N, Rajeswaran G. The imaging of osteomyelitis. Quant Imaging Med Surg. Apr 2016;6(2):184-98. doi:10.21037/qims.2016.04.01
19. Ferreira TA, Saraiva P, Genders SW, Buchem MV, Luyten GPM, Beenakker JW. CT and MR imaging of orbital inflammation. Neuroradiology. Dec 2018;60(12):1253-1266. doi:10.1007/s00234-018-2103-4
20. Tawfik HA, Abdelhalim A, Elkafrawy MH. Computed tomography of the orbit - A review and an update. Saudi J Ophthalmol. Oct 2012;26(4):409-18. doi:10.1016/j.sjopt.2012.07.004
21. 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. Dec 2002;6(6):337-47. doi:10.1067/mpa.2002.129040
22. Kadom N. Pediatric strabismus imaging. Curr Opin Ophthalmol. Sep 2008;19(5):371-8. doi:10.1097/ICU.0b013e328309f165
23. Engle EC. The genetic basis of complex strabismus. Pediatr Res. Mar 2006;59(3):343-8. doi:10.1203/01.pdr.0000200797.91630.08
24. Behbehani R. Clinical approach to optic neuropathies. Clin Ophthalmol. Sep 2007;1(3):233-46.
25. Lawson GR. Controversy: Sedation of children for magnetic resonance imaging. Arch Dis Child. Feb 2000;82(2):150-3. doi:10.1136/adc.82.2.150
26. Kirsch CFE. Imaging of Sella and Parasellar Region. Neuroimaging Clin N Am. Nov 2021;31(4):541-552. doi:10.1016/j.nic.2021.05.010
27. Chaudhary V, Bano S. Imaging of the pituitary: Recent advances. Indian J Endocrinol Metab. Sep 2011;15 Suppl 3(Suppl3):S216-23. doi:10.4103/2230-8210.84871
28. American College of Radiology. ACR Appropriateness Criteria® Neuroendocrine Imaging. American College of Radiology. Updated 2018. Accessed January 23, 2023. https://acsearch.acr.org/docs/69485/Narrative/
29. Wu LM, Li YL, Yin YH, et al. Usefulness of dual-energy computed tomography imaging in the differential diagnosis of sellar meningiomas and pituitary adenomas: preliminary report. PLoS One. 2014;9(3):e90658. doi:10.1371/journal.pone.0090658
30. Freda PU, Beckers AM, Katznelson L, et al. Pituitary incidentaloma: an endocrine society clinical practice guideline. J Clin Endocrinol Metab. Apr 2011;96(4):894-904. doi:10.1210/jc.2010-1048
31. Cunnane MB. Imaging of Tinnitus. Neuroimaging Clin N Am. Feb 2019;29(1):49-56. doi:10.1016/j.nic.2018.09.006
32. American College of Radiology. ACR Appropriateness Criteria® Hearing Loss and/or Vertigo. American College of Radiology. Updated 2018. Accessed December 30, 2022. https://acsearch.acr.org/docs/69488/Narrative
33. 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. doi:10.2484/rcr.v5i2.437
34. Verbist BM. Imaging of sensorineural hearing loss: a pattern-based approach to diseases of the inner ear and cerebellopontine angle. Insights Imaging. Apr 2012;3(2):139-53. doi:10.1007/s13244-011-0134-z
35. Trojanowska A, Drop A, Trojanowski P, Rosińska-Bogusiewicz K, Klatka J, Bobek-Billewicz B. External and middle ear diseases: radiological diagnosis based on clinical signs and symptoms. Insights Imaging. Feb 2012;3(1):33-48. doi:10.1007/s13244-011-0126-z
36. Juliano AF, Ginat DT, Moonis G. Imaging Review of the Temporal Bone: Part II. Traumatic, Postoperative, and Noninflammatory Nonneoplastic Conditions. Radiology. Sep 2015;276(3):655-72. doi:10.1148/radiol.2015140800
37. Joshi VM, Navlekar SK, Kishore GR, Reddy KJ, Kumar EC. CT and MR imaging of the inner ear and brain in children with congenital sensorineural hearing loss. Radiographics. May-Jun 2012;32(3):683-98. doi:10.1148/rg.323115073
38. Dewan K, Wippold FJ, 2nd, Lieu JE. Enlarged vestibular aqueduct in pediatric sensorineural hearing loss. Otolaryngol Head Neck Surg. Apr 2009;140(4):552-8. doi:10.1016/j.otohns.2008.12.035
39. Ralli M, Rolesi R, Anzivino R, Turchetta R, Fetoni AR. Acquired sensorineural hearing loss in children: current research and therapeutic perspectives. Acta Otorhinolaryngol Ital. Dec 2017;37(6):500-508. Sordità infantile acquisita: stato dell’arte della ricerca e prospettive terapeutiche. doi:10.14639/0392-100x-1574
40. American College of Radiology. ACR Appropriateness Criteria® Tinnitus. American College of Radiology. Updated 2017. Accessed December 30, 2022. https://acsearch.acr.org/docs/3094199/Narrative/
41. Pegge SAH, Steens SCA, Kunst HPM, Meijer FJA. Pulsatile Tinnitus: Differential Diagnosis and Radiological Work-Up. Curr Radiol Rep. 2017;5(1):5. doi:10.1007/s40134-017-0199-7
42. Yew KS. Diagnostic approach to patients with tinnitus. Am Fam Physician. Jan 15 2014;89(2):106-13.
43. Kann K. Acute Mastoiditis: Pearls and Pitfalls. emDOCs. Updated March 27, 2016. Accessed December 30, 2022. http://www.emdocs.net/acute-mastoiditis-pearls-and-pitfalls/
44. Luntz M, Bartal K, Brodsky A, Shihada R. Acute mastoiditis: the role of imaging for identifying intracranial complications. Laryngoscope. Dec 2012;122(12):2813-7. doi:10.1002/lary.22193
45. Patel KM, Almutairi A, Mafee MF. Acute otomastoiditis and its complications: Role of imaging. Operative Techniques in Otolaryngology-Head and Neck Surgery. 2014/03/01 2014;25(1):21-28. doi:https://doi.org/10.1016/j.otot.2013.11.004
46. Platzek I, Kitzler HH, Gudziol V, Laniado M, Hahn G. Magnetic resonance imaging in acute mastoiditis. Acta Radiol Short Rep. Feb 2014;3(2):2047981614523415. doi:10.1177/2047981614523415
47. Gomaa MA, Abdel Karim AR, Abdel Ghany HS, Elhiny AA, Sadek AA. Evaluation of temporal bone cholesteatoma and the correlation between high resolution computed tomography and surgical finding. Clin Med Insights Ear Nose Throat. 2013;6:21-8. doi:10.4137/cment.S10681
48. Baráth K, Huber AM, Stämpfli P, Varga Z, Kollias S. Neuroradiology of cholesteatomas. AJNR Am J Neuroradiol. Feb 2011;32(2):221-9. doi:10.3174/ajnr.A2052
49. Chen Y, Li P. Application of high resolution computer tomography in external ear canal cholesteatoma diagnosis. J Otol. Mar 2018;13(1):25-28. doi:10.1016/j.joto.2017.10.004
50. Hiremath SB, Gautam AA, Sasindran V, Therakathu J, Benjamin G. Cerebrospinal fluid rhinorrhea and otorrhea: A multimodality imaging approach. Diagn Interv Imaging. Jan 2019;100(1):3-15. doi:10.1016/j.diii.2018.05.003
51. Vemuri NV, Karanam LSP, Manchikanti V, Dandamudi S, Puvvada SK, Vemuri VK. Imaging review of cerebrospinal fluid leaks. Indian J Radiol Imaging. Oct-Dec 2017;27(4):441-446. doi:10.4103/ijri.IJRI_380_16
52. Collins JM, Krishnamoorthy AK, Kubal WS, Johnson MH, Poon CS. Multidetector CT of temporal bone fractures. Semin Ultrasound CT MR. Oct 2012;33(5):418-31. doi:10.1053/j.sult.2012.06.006
53. Kennedy TA, Avey GD, Gentry LR. Imaging of temporal bone trauma. Neuroimaging Clin N Am. Aug 2014;24(3):467-86, viii. doi:10.1016/j.nic.2014.03.003
54. Lantos JE, Leeman K, Weidman EK, Dean KE, Peng T, Pearlman AN. Imaging of Temporal Bone Trauma: A Clinicoradiologic Perspective. Neuroimaging Clin N Am. Feb 2019;29(1):129-143. doi:10.1016/j.nic.2018.08.005
55. Bożek P, Kluczewska E, Misiołek M, Ścierski W, Lisowska G. 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. doi:10.12659/msm.898546
56. 56. Muderris T, Bercin S, Sevil E, Cetin H, Kiris M. A potentially catastrophic anatomical variation: aberrant internal carotid artery in the middle ear cavity. Case Rep Otolaryngol. 2013;2013:743021. doi:10.1155/2013/743021
57. Muncie HL, Sirmans SM, James E. Dizziness: Approach to Evaluation and Management. Am Fam Physician. Feb 1 2017;95(3):154-162.
58. Strupp M, Dieterich M, Brandt T. The treatment and natural course of peripheral and central vertigo. Dtsch Arztebl Int. Jul 2013;110(29-30):505-15; quiz 515-6. doi:10.3238/arztebl.2013.0505
59. 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. Sep-Oct 2010;31(5):339-42. doi:10.1016/j.amjoto.2009.04.003

ADDITIONAL RESOURCES

1. Beck RW, Cleary PA, Anderson MM, Jr., et al. A randomized, controlled trial of corticosteroids in the treatment of acute optic neuritis. The Optic Neuritis Study Group. N Engl J Med. Feb 27 1992;326(9):581-8. doi:10.1056/nejm199202273260901

Coding Section 

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 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 2024 Forward     

01012024  NEW POLICY