Temporal Bone Fractures Workup

  • Author: Antonio Riera March, MD, FACS; Chief Editor: Arlen D Meyers, MD, MBA   more...
 
Updated: Jun 23, 2010
 

Imaging Studies

Most patients with temporal bone fracture have already had a CT scan of the head to rule out or identify intracranial injuries.

  • High-resolution CT (HRCT) of the temporal bone is useful in assessing injuries complicated by CSF leak, facial paralysis, or suspected vascular injury. Axial and coronal images are usually obtained with 1-mm sections, as are magnified views of the temporal bone. Bone windows are necessary. Axial high-resolution CT of a fractured right temporal bone is seen below. Axial high-resolution CT of the right temporal bonAxial high-resolution CT of the right temporal bone that represents a longitudinal fracture line that extends from the roof of the external auditory canal to the middle ear cavity.
  • HRCT of the temporal bone is indicated if surgical intervention for management of otologic complications is required.
  • If transient or persistent neurologic deficits are present in a patient with basilar skull fracture, HRCT of temporal bone with CT angiography is indicated to evaluate for petrous carotid injury.
  • Magnetic resonance imaging (MRI) can not identify temporal bone fracture. MRI has both poor sensitivity and specificity in this respect. MRI is useful in assessment of the intracranial contents and/or a nerve palsy not explained by the HRCT .[1, 14, 15] It also can identify intralabyrinthine hemorrhage, brainstem injury, nerve compression, and herniation of intracranial contents into the mastoid cavity .[1] MRI is also useful prior to neurosurgical intervention for temporal bone fractures, particularly with a middle cranial fossa approach.[14]
Next

Other Tests

Maximum stimulation test

This test is based on the observation of twitch of the facial musculature using the Hilger facial nerve stimulator after the third day of the injury. It is used only in the case of complete facial nerve paralysis (as determined by the House-Brackman grading) because of the pain caused by the facial stimulation. Supramaximal stimulation is applied with a maximal tolerated current on the normal side. The affected side is compared with the normal side, using the same stimulating current. An absent or markedly decreased response (barely perceptible movement) indicate a poor and incomplete return of facial nerve function.

Nerve excitability test (minimal nerve excitability test)

This test is similar to the previous test that used the Hilger nerve stimulator after the third day of injury; this test compares the amperage site-to-site necessary to initiate a barely visible response on the affected side. A difference of 3.5 mA or more is significant, carries a poor prognosis, and indicates the need to consider surgical exploration.

Electroneurography

Electroneurography (ENOG) is the technique designed by Fisch. It is used every 2 days between the third and the 21st day after the initial trauma. The results are expressed as a percentage of the amplitude of the action potentials on the paralyzed side as compared with the nonparalyzed side. The results correlate well with the percentage of nerve degeneration. According to Fisch, 90% degeneration of the involved nerve is considered significant and represents the threshold for surgical management.[16]

Fisch has developed accepted indications for surgical management based on the “percentage of nerve degeneration,” advocating exploration and decompression or repair when the ENOG indicates 90% degeneration. In other words, degeneration with 10% or less of nerve function compared with the normal side is considered the critical turning point for surgical management recommendation. Fisch found, histologically, that traumatic injury at the geniculate ganglion induces retrograde degeneration through the labyrinthine and distal meatal segments of the facial nerve. Fisch believes that fibrosis occurs and blocks regenerating fibers and, therefore, advises early surgery in order to avoid this fibrotic complication within the fallopian canal.

Nosan et al believe that ENOG is of paramount importance in determining the need for and the timing of surgery for facial paralysis after trauma. They believe that ENOG has made the determination of the clinical onset of paralysis less necessary and that patients with delayed paralysis can have more severe injuries than those patients with more rapid ENOG degeneration. They believe that the time of paralysis from onset of injury should not confuse the issue.

Electromyography

Normal resting muscle does not produce spontaneous electrical activity. Spontaneous electromyographic activity (fibrillation potentials) found in the muscle indicates complete denervation. Take into consideration that fibrillation potentials take at least 3 weeks to be detected with electromyography. The presence of voluntary motor units (polyphasic action potentials), on the contrary, is a good prognostic factor and the best indicator that regeneration is taking place.

The surgical approach is controversial. Some authorities advocate limited exploration of the facial nerve based on clinical and radiographic information. Fisch, on the other hand, advocates total facial nerve exploration and decompression by a middle fossa and transmastoid approach. In patients who have total sensorineural hearing loss, Fisch suggests a translabyrinthine approach.

Previous
Proceed to Treatment & Management
 
 
Contributor Information and Disclosures
Author

Antonio Riera March, MD, FACS  Associate Professor, Department of Otolaryngology-Head and Neck Surgery, University of Puerto Rico School of Medicine

Antonio Riera March, MD, FACS is a member of the following medical societies: American Academy of Otolaryngology-Head and Neck Surgery, American Cleft Palate/Craniofacial Association, American College of Surgeons, and Society for Ear, Nose and Throat Advances in Children

Disclosure: Nothing to disclose.

Coauthor(s)

Sarah Connell, MD  Fellow, Department of Otolaryngology, Head and Neck Surgery, University of Miami, Jackson Memorial Hospital

Sarah Connell, MD is a member of the following medical societies: American Academy of Facial Plastic and Reconstructive Surgery, American Academy of Otolaryngology-Head and Neck Surgery, American Cleft Palate/Craniofacial Association, and Triological Society

Disclosure: Nothing to disclose.

Peter C Belafsky, MD, MPH, PhD  Assistant Professor, Department of Otolaryngology, University of California at Davis

Peter C Belafsky, MD, MPH, PhD is a member of the following medical societies: American Academy of Otolaryngology-Head and Neck Surgery

Disclosure: Nothing to disclose.

Specialty Editor Board

Jack A Shohet, MD  President, Shohet Ear Associates Medical Group, Inc; Associate Clinical Professor, Department of Otolaryngology-Head and Neck Surgery, University of California, Irvine, School of Medicine

Jack A Shohet, MD is a member of the following medical societies: American Academy of Otolaryngology-Head and Neck Surgery, American Medical Association, American Neurotology Society, American Tinnitus Association, and California Medical Association

Disclosure: Nothing to disclose.

Francisco Talavera, PharmD, PhD  Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Medscape Salary Employment

Peter S Roland, MD  Professor, Department of Neurological Surgery, Professor and Chairman, Department of Otolaryngology-Head and Neck Surgery, Director of Clinical Center for Auditory, Vestibular and Facial Nerve Disorders, Chief of Pediatric Otology, University of Texas Southwestern Medical Center; Adjunct Professor of Communicative Disorders, University of Texas School of Human Development

Peter S Roland, MD is a member of the following medical societies: Alpha Omega Alpha, American Academy of Otolaryngic Allergy, American Academy of Otolaryngology-Head and Neck Surgery, American Auditory Society, American Laryngological Rhinological and Otological Society, American Neurotology Society, American Otological Society, North American Skull Base Society, and Society of University Otolaryngologists-Head and Neck Surgeons

Disclosure: Alcon Labs Honoraria Speaking and teaching; Advanced Bionics Honoraria Board membership; Cochlear Corp Honoraria Board membership; Med El Corp travel grants Consulting; Foresight Consulting fee Consulting

Christopher L Slack, MD  Private Practice in Otolaryngology and Facial Plastic Surgery, Associated Coastal ENT; Medical Director, Treasure Coast Sleep Disorders

Christopher L Slack, MD is a member of the following medical societies: Alpha Omega Alpha, American Academy of Facial Plastic and Reconstructive Surgery, American Academy of Otolaryngology-Head and Neck Surgery, and American Medical Association

Disclosure: Nothing to disclose.

Chief Editor

Arlen D Meyers, MD, MBA  Professor of Otolaryngology, Dentistry, and Engineering, University of Colorado School of Medicine

Arlen D Meyers, MD, MBA is a member of the following medical societies: American Academy of Facial Plastic and Reconstructive Surgery, American Academy of Otolaryngology-Head and Neck Surgery, and American Head and Neck Society

Disclosure: Covidien Corp Consulting fee Consulting; US Tobacco Corporation Unrestricted gift Unknown; Axis Three Corporation Ownership interest Consulting; Omni Biosciences Ownership interest Consulting; Sentegra Ownership interest Board membership; Medvoy Ownership interest Management position; Cerescan Imaging Consulting; Headwatersmb Consulting fee Consulting; Venturequest Royalty Consulting

Additional Contributors

The authors and editors of Medscape Reference gratefully acknowledge the contributions of previous author Mark L Belafsky, MD, FACS, to the development and writing of this article.

The author wishes to acknowledge Joan Flaherty, RN, for her editorial assistance.

References

  1. Johnson F., Semaan M. T., Megerian C. A. Temporal Bone Fracture: Evaluation and Management in the Modern Era. Otolaryngol. Clin. N. Am. 2008;41:597-618.

  2. Alvi A, Bereliani A. Acute intracranial complications of temporal bone trauma. Otolaryngol Head Neck Surg. Dec 1998;119(6:609-613.

  3. Darrouzet V, Duclos JY, Liguoro D, Truilhe Y, De Bonfils C, Bebear JP. Management of facial paralysis resulting from temporal bone fractures: Our experience in 115 cases. Otolaryngol Head Neck Surg. Jul 2001;125(1):77-84.

  4. Lee D, Honrado C, Har-El G, Goldsmith A. Pediatric temporal bone fractures. Laryngoscope. Jun 1998;108(6):816-821.

  5. Lee D, Honrado C, Har-El G, Goldsmith A. Pediatric temporal bone fractures. Laryngoscope. Jun 1998;108(6):816-21. [Medline].

  6. Ulrich K. Verletzungen des Gehorlorgans bel Schadelbasisfrakturen(Ein Histologisch und Klinissche Studie). Acta Otolaryngol Suppl. 1926;6:1-150.

  7. Ghorayeb BY, Yeakley JW. Temporal bone fractures: longitudinal or oblique? The case for oblique temporal bone fractures. Laryngoscope. Feb 1992;102(2):129-34. [Medline].

  8. Kerr AG, Smyth GDL. Ear Trauma. In: Maran AGD, Stell PM. Clinical Otolaryngology. Blackwell Scientific Publications; 1979:113-114.

  9. Olsson JE, Shagets FW, MC, USAF. Blunt Trauma of the Temporal Bone. American Academy of Otolaryngology-Head and Neck Surgery Fo.; Second Edition 1986. A Self-Instructional Package from the Committee on Continuing Education in Otolaryngology.

  10. Diaz R, Brodie HA. Middle Ear and Temporal Bone Trauma. In: Cummings CW, Haughey BH, Thomas JR, Harker LA, Flint PW. Otolaryngology-Head and Neck Surgery. 4. Fourth edition. Elsevier Mosby; 2005:2057-2079/139.

  11. Ghorayeb BY, Yeakley JW, Hall JW 3d, Jones BE. Unusual complications of temporal bone fractures. Arch Otolaryngol Head Neck Surg. Jul 1987;113(7):749-53. [Medline].

  12. Woodcock R. Temporal Bone, Fractures. eMedicine from WebMD [serial online]. Available at http://emedicine.medscape.com/article/385039-overview.

  13. Ghorayeb BY, Yeakley JW, Hall JW 3rd, Jones BE. Unusual complications of temporal bone fractures. Arch Otolaryngol Head Neck Surg. Jul 1987;113(7):749-53. [Medline].

  14. Jones RM, Rothman MI, Gray WC, Zoarski GH, Mattox DE. Temporal lobe injury in temporal bone fractures. Arch Otolaryngol Head Neck Surg. 2000;126 (2):131-135.

  15. Schuknecht B, Graetz K. Radiologic assessment of maxillofacial, mandibular, and skull base trauma. Eur Radiol. Mar 2005;15(3):560-8. [Medline].

  16. Fisch U. Facial paralysis in fractures of the petrous bone. Laryngoscope. Dec 1974;84(12):2141-54. [Medline].

  17. Hough JV, Stuart WD. Middle ear injuries in skull trauma. Laryngoscope. Jun 1968;78(6):899-937. [Medline].

  18. Brodie HA, Thompson TC. Management of complications from 820 temporal bone fractures. Am J Otol. Mar 1997;18(2):188-97. [Medline].

  19. MacGee EE, Cauthen JC, Brackett CE. Meningitis following acute traumatic cerebrospinal fluid fistula. J Neurosurg. Sep 1970;33(3):312-6. [Medline].

  20. Rathmore MH. Do prophylactic antibiotics prevent meningitis after basilar skull fracture?. Ped Inf Dis J. Feb 1991;10(2):87-88. [Medline].

  21. Demetriades D, Charalambides D, Lakhoo M, Pantanowitz D. Role of prophylactic antibiotics in open and basilar fractures of the skull: a randomized study. Injury. 1992;23(6):377-80. [Medline].

  22. Villalobos T, Arango C, Kubilis P, Rathore M. Antibiotic prophylaxis after basilar skull fractures: a meta-analysis. ALYSIS. Aug 1998;27(2):364-9. [Medline].

  23. Leech PJ, Paterson A. Conservative and operative management for cerebrospinal-fluid leakage after closed head injury. Lancet. May 12 1973;1(7811):1013-6. [Medline].

  24. Turner JWA. Facial paralysis in closed head injuries. Lancet. 1944;246:756-57.

  25. Maiman DJ, Cusick JF, Anderson AJ, Larson SJ. Nonoperative management of traumatic facial nerve palsy. J Trauma. Jul 1985;25(7):644-8. [Medline].

  26. Arriaga Moises A. Traumatic Facial Paralysis. In: Gates George A. Current Therapy in Otolaryngology-Head and Neck Surgery. Sixth Edition. Mosby; 1998:121-125.

  27. Barber HO. Head injury audiological and vestibular findings. Ann Otol Rhinol Laryngol. Apr 1969;78(2):239-52. [Medline].

  28. Bobad MS. Eagle syndrome caused by traumatic fracture of a mineralized stylohyoid ligament: literature review and case report. Journ Craniomand Pract. 1995;13(3):189-92.

  29. Brodie HA. Management of Temporal Bone Trauma. In: Bailey Byron J. & Johnson Jonas T. Head & Neck Surgery-Otolaryngology. Vol. 2. 4th edition. Lippincott Williams & Wilkins; 2006:125/2848-2866.

  30. Cannon CR, Jahrsdoerfer RA. Temporal bone fractures. Review of 90 cases. Arch Otolaryngol. May 1983;109(5):285-8. [Medline].

  31. Chang CY, Cass SP. Management of facial nerve injury due to temporal bone trauma. Am J Otol. Jan 1999;20(1):96-114. [Medline].

  32. Clark JM, Shockley WW. Management and Reanimation of the Paralyzed Face. In: Papel Ira D. Facial Plastic and Reconstructive Surgery. Second Edition. Thieme; 2002:660-685/53.

  33. Darrouzet V, Duclos JY, Liguoro D, Truilhe Y, De Bonfils C, Bebear JP. Management of facial paralysis resulting from temporal bone fractures: Our experience in 115 cases. Otolaryngol Head Neck Surg. Jul 2001;125(1):77-84. [Medline].

  34. DiBiase P, Arriaga MA. Post-traumatic hydrops. Otolaryngol Clin North Am. Dec 1997;30(6):1117-22. [Medline].

  35. Eagle WW. Elongated styloid process: report of two cases. Arch Otolaryn Head Neck Surg. 1937;25:584-87.

  36. Felix H, Eby TL, Fisch U. New aspects of facial nerve pathology in temporal bone fractures. Acta Otolaryngol. 1991;111(2):332-6. [Medline].

  37. Fisch U. Current surgical treatment of intratemporal facial palsy. Clin Plast Surg. Jul 1979;6(3):377-88. [Medline].

  38. Gianoli GJ, Amedee RG. Temporal bone fractures. J La State Med Soc. Oct 1989;141(10):11-3. [Medline].

  39. Girdjian ES, Lissnerl IR. Deformation of the skull in head injury studied by the "Stesscoat" technique, quantitative determinations. Surg Gynecol Obstret. 1946;83:219-233.

  40. Goodwin WJ Jr. Temporal bone fractures. Otolaryngol Clin North Am. Aug 1983;16(3):651-9. [Medline].

  41. Grahne B. Traumatic cranionasal fistulas persistent cerebrospinal fluid rhinorrhoea and their repair with frontal sinus osteoplasty. Acta Otolaryngol. Nov-Dec 1970;70(5):392-400. [Medline].

  42. Griffin JE, Altenau MM, Schaefer SD. Bilateral longitudinal temporal bone fractures: a retrospective review of seventeen cases. Laryngoscope. Sep 1979;89(9 Pt 1):1432-5. [Medline].

  43. Hagan WE, Tabb HG, Cox RH, Travis LW. Gunshot injury to the temporal bone: an analysis of thirty-five cases. Laryngoscope. Aug 1979;89(8):1258-72. [Medline].

  44. Kahn JB, Stewart MG, Diaz-Marchan PJ. Acute temporal bone trauma: utility of high-resolution computed tomography. Am J Otol. Sep 2000;21(5):743-52. [Medline].

  45. Lambert PR, Brackmann DE. Facial paralysis in longitudinal temporal bone fractures: a review of 26 cases. Laryngoscope. Aug 1984;94(8):1022-6. [Medline].

  46. Lyos AT, Marsh MA, Jenkins HA, Coker NJ. Progressive hearing loss after transverse temporal bone fracture. Arch Otolaryngol Head Neck Surg. Jul 1995;121(7):795-9. [Medline].

  47. McKennan KX, Chole RA. Facial paralysis in temporal bone trauma. Am J Otol. Mar 1992;13(2):167-72. [Medline].

  48. McKennan KX, Chole RA. Post-traumatic cholesteatoma. Laryngoscope. Aug 1989;99(8 Pt 1):779-82. [Medline].

  49. Meriot P, Veillon F, Garcia JF, Nonent M, Jezequel J, Bourjat P, et al. CT appearances of ossicular injuries. Radiographics. Nov-Dec 1997;17(6):1445-54. [Medline].

  50. Morgan WE, Coker NJ, Jenkins HA. Histopathology of temporal bone fractures: implications for cochlear implantation. Laryngoscope. Apr 1994;104(4):426-32. [Medline].

  51. Nelson EL, Melton LJ 3rd, Annegers JF, Laws ER, Offord KP. Incidence of skull fractures in Olmsted County, Minnesota. Neurosurgery. Sep 1984;15(3):318-24. [Medline].

  52. Nosan DK, Benecke JE Jr, Murr AH. Current perspective on temporal bone trauma. Otolaryngol Head Neck Surg. Jul 1997;117(1):67-71. [Medline].

  53. Ort S, Beus K. Pediatric temporal bone fractures in a rural population. Otolaryngology Head Neck Surgery. 2004;131:433-437.

  54. Quaranta A, Campobasso G, Piazza F, Quaranta N, Salonna I. Facial nerve paralysis in temporal bone fractures: outcomes after late decompression surgery. Acta Otolaryngol. Jul 2001;121(5):652-5. [Medline].

  55. Resnick DK, Subach BR, Marion DW. The significance of carotid canal involvement in basilar cranial fracture. Neurosurgery. Jun 1997;40(6):1177-81. [Medline].

  56. Ryall RG, Peacock MK, Simpson DA. Usefulness of beta 2-transferrin assay in the detection of cerebrospinal fluid leaks following head injury. J Neurosurg. Nov 1992;77(5):737-9. [Medline].

  57. Schindler JS, Niparko JK. Imaging quiz case 1. Transverse temporal bone fractures (left) with subsequent progressive SNHL, consistent with sympathetic cochleolabyrinthitis. Arch Otolaryngol Head Neck Surg. Jul 1998;124(7):814-818. [Medline].

  58. Schuknecht HF. A clinical study of auditory damage following blows to the head. Ann Otol Rhinol Laryngol. Jun 1950;59(2):331-58. [Medline].

  59. Shindo ML, Fetterman BL, Shih L, Maceri DR, Rice DH. Gunshot wounds of the temporal bone: a rational approach to evaluation and management. Otolaryngol Head Neck Surg. Apr 1995;112(4):533-9. [Medline].

  60. Spetzler RF, Wilson CB. Management of recurrent CSF rhinorrhea of the middle and posterior fossa. J Neurosurg. 1998;49:393-97. [Medline].

  61. Stone JA, Castillo M, Neelon B, Mukherji SK. Evaluation of CSF leaks: high-resolution CT compared with contrast-enhanced CT and radionuclide cisternography. Am J Neuroradiol. Apr 1999;20(4):706-12. [Medline].

  62. Travis LW, Stalnaker RL, Melvin JW. Impact trauma of the human temporal bone. J Trauma. Oct 1977;17(10):761-6. [Medline].

  63. Tuohimaa P. Vestibular disturbances after acute mild head injury. Acta Ololaryngol (Suppl). 1978;359:1-67. [Medline].

  64. Weissman JL, Curtin HD. Pneumolabyrinth: a computed tomographic sign of temporal bone fracture. Am J Otolaryngol. Mar-Apr 1992;13(2):113-4. [Medline].

  65. Wennmo C, Spandow O. Fractures of the temporal bone--chain incongruencies. Am J Otolaryngol. Jan-Feb 1993;14(1):38-42. [Medline].

  66. Wennmo C, Svensson C. Temporal bone fractures. Vestibular and other related ear sequele. Acta Otolaryngol Suppl. 1989;468:379-83. [Medline].

  67. Yanagihara N, Murakami S, Nishihara S. Temporal bone fractures inducing facial nerve paralysis: a new classification and its clinical significance. Ear Nose Throat J. Feb 1997;76(2):79-80, 83-6. [Medline].

  68. Yeakley JW. Temporal bone fractures. Curr Probl Diagn Radiol. May-Jun 1999;28(3):65-98. [Medline].

  69. Ylikoski J, Palva T, Sanna M. Dizziness after head trauma: clinical and morphologic findings. Am J Otol. Apr 1982;3(4):343-52. [Medline].

 
Previous
Next
 
Internal aspect of the skull base: arcuate eminence (AE), cochlea (C), foramen magnum (FM), internal auditory canal (IAC), foramen lacerum (L), foramen ovale (O), foramen rotundum (R), foramen spinosum (SP), sigmoid sinus (SS), transverse sinus (TS), vestibular system (V).
External aspect of the skull base: carotid canal (C), condyle (CO), foramen magnum (FM), jugular foramen (J), foramen lacerum (L), foramen ovale (O), pterygoid plates (P), styloid foramen (S), foramen spinosum (SP).
Internal aspect of the skull base that represents, in black and blue colors, the pathway of the longitudinal temporal bone fracture lines.
Internal aspect of the skull base that represents, in black and red colors, the pathways of the transverse temporal bone fracture lines.
Axial high-resolution CT of the right temporal bone that represents a longitudinal fracture line that extends from the roof of the external auditory canal to the middle ear cavity.
Right temporal bone transverse fracture with severe spontaneous nystagmus (third degree) manifesting immediately after trauma. The fast component beats away from the fracture site in all directions of the gaze; the intensity of the spontaneous nystagmus is represented by the different lengths of black arrows. This type of nystagmus is usually seen by the naked eye. According to Alexander's law, the nystagmus increases when the eyes are turned in the direction of the quick component and decreases when the eyes are turned in the direction of the slow component.
Internal aspect of the skull base depicting, in green color, a mixed temporal bone fracture line with both a longitudinal pattern (circle) and a transverse pattern (rectangle).
Table 1. Longitudinal and Transverse Fractures
FeatureLongitudinal FracturesTransverse Fractures
IncidenceApproximately 80%Approximately 20%
MechanismTemporal or parietal traumaFrontal or occipital trauma
CSF otorrheaCommonOccasional
Tympanic membrane perforationCommonRare
Facial nerve damage20% (most often temporary and frequently delayed in onset)50% (severe, usually permanent, and immediate in onset)
Hearing lossCommon (conductive type and possibly high tone neurosensorial secondary to concomitant inner ear concussion)Common (severe sensorineural or mixed)
HemotympanumCommon (associated with otorrhagia)Possible (not associated with otorrhagia)
NystagmusCommon (usually spontaneous, usually less intense [first or second degree] or positional; nystagmus absence also possible)Common (intense [third degree], spontaneous, fast component beating to the opposite ear, long lasting; positional nystagmus also possible before and after compensation period)
OtorrhagiaCommonRare
VertigoCommon (less intense, and/or positional; absence is also possible)Common (intense, usually associated in the acute phase with nausea and possibly vomiting)
Table 2. Otic Capsule–Sparing and Otic Capsule–Disrupting Fractures
FeatureOtic Capsule SparingOtic Capsule Disrupting
IncidenceApproximately 95%Approximately 5%
MechanismTemporal or parietal traumaOccipital trauma
Line of fractureAnterolateral to the otic capsuleThrough the otic capsule
Pathway
  • Squamosa portion of temporal bone
  • Posterosuperior wall of the external auditory canal and tympanic membrane commonly involved
  • Also, mastoid air cells and middle ear
  • Foramen magnum, petrous pyramid, and otic capsule
  • Also jugular foramen, internal auditory canal, and foramen lacerum
  • Tympanic membrane and external auditory canal not usually affected
CSF leakMiddle cranial fossa (tegmen mastoideum, tegmen tympani, middle ear, and external auditory canal or eustachian tube)Posterior cranial fossa (middle ear, eustachian tube)
Ossicular chain involvementCommonRare
Hearing lossConductive or mixedSensorineural
Facial paralysisLess commonCommon
Previous
Next
 
 
 
 
 
All material on this website is protected by copyright, Copyright © 1994-2012 by WebMD LLC.
This website also contains material copyrighted by 3rd parties.

DISCLAIMER: The content of this Website is not influenced by sponsors. The site is designed primarily for use by qualified physicians and other medical professionals. The information contained herein should NOT be used as a substitute for the advice of an appropriately qualified and licensed physician or other health care provider. The information provided here is for educational and informational purposes only. In no way should it be considered as offering medical advice. Please check with a physician if you suspect you are ill.