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Positional relationship between the external acoustic meatus and sigmoid sinus: an MRI study

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Abstract

Purpose

There is no study exploring the positional relationship between the external acoustic meatus (EAM) and the sigmoid sinus (SS) in detail. The present study aimed to characterize the relationship using contrast magnetic resonance imaging (MRI).

Methods

In total, 85 patients with an intact EAM, SS, and surrounding structures underwent thin-sliced, contrast MRI. Imaging data were transferred to a workstation for analysis.

Results

In all patients, the EAM and SS were well depicted on both the sagittal and axial images. The relationships and distances between the EAM and SS, in addition to the shape of cross sections of the EAM, were highly variable with left–right asymmetry. The positional relationships between the EAM and the anterior edge of the SS were classified into superior, intervening, and inferior types. The intervening type was the most predominant, accounting for 85%. The shortest distance between the posterior wall of the EAM and the anterior margin of the SS was 12.3 ± 3.9 mm on the right side and 13.0 ± 2.9 mm on the left. In three women, the distance was less than 5 mm on the right side.

Conclusions

The positional relationship between the EAM and SS is highly variable and inconsistent. These structures may be adjacent, especially on the right side, and presurgical contrast MRI should be included when planning surgeries around the EAM.

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References

  1. Chawla A, Ezhil Bosco JI, Lim TC, Shenoy JN, Krishnan V (2015) Computed tomography features of external auditory canal cholesteatoma: a pictorial review. Curr Probl Diagn Radiol 44:511–516

    Article  Google Scholar 

  2. Cisneros JC, Lopes PT, Bento RF, Tsuji RK (2017) Sinus pericranii, petrosquamosal sinus and extracranial sigmoid sinus: anatomical variations to consider during a retroauricular approach. Auris Nasus Larynx 44:359–364

    Article  Google Scholar 

  3. Çam OH, Karataş M (2015) A life threatening pitfall in ear surgery: extracranial sigmoid sinus. J Craniofac Surg 26:e619–e620

    Article  Google Scholar 

  4. Deguine C, Pulec JL (1997) Attic cholesteatoma with erosion of the superior bony canal wall. Ear Nose Throat 76:848

    Article  CAS  Google Scholar 

  5. Gangopadhyay K, McArthur PD, Larsson SG (1996) Unusual anterior course of the sigmoid sinus: report of a case and review of the literature. J Laryngol Otol 110:984–986

    Article  CAS  Google Scholar 

  6. Ichijo H, Hosokawa M, Shinkawa H (1996) The relationship between mastoid pneumatization and the position of the sigmoid sinus. Eur Arch Otorhinolaryngol 253:421–424

    Article  CAS  Google Scholar 

  7. Kennel CE, Puricelli MD, Rivera AL (2019) Surgically-relevant anatomy of the external auditory canal bulge and scutum. Otol Neurotol 40:e1037–e1044

    Article  Google Scholar 

  8. Lansley JA, Tucker W, Eriksen MR, Riordan-Eva P, Connor SEJ (2017) Sigmoid sinus diverticulum, dehiscence, and venous sinus stenosis: potential causes of pulsatile tinnitus in patients with idiopathic intracranial hypertension? AJNR Am J Neuroradiol 38:1783–1788

    Article  CAS  Google Scholar 

  9. McComick MW, Bartels HG, Rodriguez A, Johnson JE, Janjua RM (2016) Anatomical variations of the transverse-sigmoid sinus junction: implications for endovascular treatment of idiopathic intracranial hypertension. Anat Rec (Hoboken) 299:1037–1042

    Article  Google Scholar 

  10. McDonald TJ, Facer GW, Clark JL (1986) Surgical treatment of the external auditory canal. Laryngoscope 96:830–833

    Article  CAS  Google Scholar 

  11. Raso JL, Gusmão SN (2011) A new landmark for finding the sigmoid sinus in suboccipital craniotomies. Neurosurg 68:1–6

    Article  Google Scholar 

  12. Ribas GC, Rhoton AL Jr, Cruz OR, Peace D (2005) Suboccipital burr holes and craniectomies. Neurosurg Focus 19:E1

    Article  Google Scholar 

  13. Roche J, Warner D (1996) Arachnoid granulations in the transverse and sigmoid sinuses: CT, MR, and MR angiographic appearance of a normal anatomic variation. AJNR Am J Neuroradiol 17:677–683

    CAS  PubMed  Google Scholar 

  14. Roland PS, Meyerhoff W, Mickey B (1991) Management of the external auditory canal in skull base surgery. Skull Base Surg 1:39–42

    Article  CAS  Google Scholar 

  15. Roychaudhuri BK, Roychowdhury A, Ghosh S, Nandy S (2011) Study on the anatomical variations of the posterosuperior bony overhang of external auditory canal. Indian J Otolaryngol Head Neck Surg 63:136–140

    Article  CAS  Google Scholar 

  16. Sirikçi A, Bayazit YA, Kervancioğlu S, Ozer E, Kanlikama M, Bayram M (2004) Assessment of mastoid air cell size versus sigmoid sinus variables with a tomography-assisted digital image processing program and morphometry. Surg Radiol Anat 26:145–148

    Article  Google Scholar 

  17. Tsutsumi S, Ono H, Yasumoto Y (2017) The mastoid emissary vein: an anatomic study with magnetic resonance imaging. Surg Radiol Anat 39:351–356

    Article  Google Scholar 

  18. Ugur HC, Dogan I, Kahilogullari G, Al-Beyati ES, Ozdemir M, Kayaci S, Comert A (2013) New practical landmarks to determine sigmoid sinus free zones for suboccipital approaches: an anatomical study. J Craniofac Surg 24:1815–1818

    Article  Google Scholar 

  19. Ulug T, Basaran B, Minareci O, Aydin K (2004) An unusual complication of stapes surgery: profuse bleeding from the anteriorly located sigmoid sinus. Eur Arch Otorhinolaryngol 261:397–399

    Article  Google Scholar 

  20. Van Osch K, Allen D, Gare B, Hudson TJ, Ladak H, Agrawal SK (2019) Morphological analysis of sigmoid sinus anatomy: clinical applications to neurological surgery. J Otolaryngol Head Neck Surg 48:2

    Article  Google Scholar 

  21. Virapongse C, Sarwar M, Sasaki C, Kier EL (1983) High resolution computed tomography of the osseous external auditory canal: 1 Normal anatomy. J Comput Assist Tomogr 7:486–492

    Article  CAS  Google Scholar 

  22. Woods A, Lagravère MO (2018) Three-dimensional changes of the auditory canal in a three-year period during adolescence using CBCTs. Int J Dent 2018:5463753

    Article  Google Scholar 

  23. Wright CG (1997) Development of the human external ear. J Am Acad Audiol 8:379–382

    CAS  PubMed  Google Scholar 

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Funding

No funding was received for this study.

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Authors and Affiliations

  1. Department of Neurological Surgery, Juntendo University Urayasu Hospital, 2-1-1 Tomioka, Urayasu, Chiba, 279-0021, Japan

    Satoshi Tsutsumi & Hisato Ishii

  2. Division of Radiological Technology, Medical Satellite Yaesu Clinic, Tokyo, Japan

    Hideo Ono

Authors
  1. Satoshi Tsutsumi
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  2. Hideo Ono
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  3. Hisato Ishii
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Contributions

ST conceived the study. HO collected the imaging data. ST and HI analyzed the imaging data. ST wrote the manuscript.

Corresponding author

Correspondence to Satoshi Tsutsumi.

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Conflict of interest

The authors have no conflicts of interest to declare regarding the materials or methods used in this study or the findings presented in this paper.

Ethical approval

All procedures performed in the studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee, and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards.

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Informed consent was obtained from all participants included in the study.

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Tsutsumi, S., Ono, H. & Ishii, H. Positional relationship between the external acoustic meatus and sigmoid sinus: an MRI study. Surg Radiol Anat 42, 791–795 (2020). https://doi.org/10.1007/s00276-020-02469-9

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  • DOI: https://doi.org/10.1007/s00276-020-02469-9

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