Hostname: page-component-78c5997874-4rdpn Total loading time: 0 Render date: 2024-11-06T00:55:48.176Z Has data issue: false hasContentIssue false

Using the processus cochleariformis as a multipurpose landmark in middle cranial fossa surgery

Published online by Cambridge University Press:  20 May 2008

T Ulug*
Affiliation:
ENT Department, Istanbul Medical Faculty, Istanbul University, Turkey
*
Address for correspondence: Prof Tuncay Ulug, ENT Department, Istanbul Medical Faculty, Istanbul University, Capa, Istanbul, Turkey. E-mail: [email protected]

Abstract

Objective:

To demonstrate that the anatomical structure known as the processus cochleariformis, with its intimate and constant relationships to inner-ear structures, can be used as a reliable landmark during middle cranial fossa surgery, alone or in conjunction with other landmarks.

Study design:

An anatomical study using cadaveric temporal bones to define six reproducible measurements that relate the processus cochleariformis to inner-ear structures, and to define 14 other measurements that relate inner-ear structures to adjacent structures within the intact bone.

Method:

Using 10 cadaver specimens, 20 reproducible measurements were defined. The first six of these defined the relation of the processus cochleariformis to inner-ear structures in the middle cranial fossa approach. The other measurements defined the exact location of the inner-ear structures and adjacent structures within the intact bone.

Results:

The vertical crest lies at a 20° angle from the processus cochleariformis to the coronal plane, and at a distance of 5 to 6 mm from the processus cochleariformis. The point at which the medial margin of the basal turn of the cochlea crosses the labyrinthine segment of the facial nerve lies at a 0° angle from the processus cochleariformis to the coronal plane, and at a distance of 6.5 to 7.5 mm from the processus cochleariformis. The superior semicircular canal lies at a 45° angle from the processus cochleariformis to the coronal plane. The other measurements obtained give important clues about the position of the cochlea, vestibulum, greater superficial petrosal nerve and labyrinthine segment of the facial nerve.

Conclusions:

If the classical landmarks are indiscernible during middle cranial fossa surgery, then the processus cochleariformis, with its intimate and constant relationships to inner-ear structures, is a safe and constant landmark.

Type
Main Articles
Copyright
Copyright © JLO (1984) Limited 2008

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Footnotes

Presented in part at the Otology 2000 Achievements and Perspectives XXII Annual Meeting of the Politzer Society, 15–19 August 1999, Zürich, Switzerland, and at International Istanbul Otorhinolaryngology Meeting-2003, 9–11 May, 2003, Istanbul, Turkey.

References

1House, WF. Middle cranial fossa approach to the petrous pyramid (report of 50 cases). Arch Otolaryngol 1963;78:7481Google Scholar
2Parry, RH. A case of tinnitus treated by division of the auditory nerve. J Laryngol Otol 1904;19:402–6CrossRefGoogle Scholar
3House, WF. Surgical exposure of the internal auditory canal and its contents through the middle cranial fossa. Laryngoscope 1961;71:1363–85CrossRefGoogle ScholarPubMed
4Lampert, PR. Classics from the Laryngoscope. House: Surgical exposure of the internal auditory canal and its contents through the middle cranial fossa (Laryngoscope 1961;71:363–85). Laryngoscope 1996;106:1195–8Google Scholar
5Wigand, ME, Haid, T, Berg, M, Rettinger, G. The enlarged transtemporal approach to the cerebellopontine angle. Technique and indications. Acta Otorhinolaryngol Ital 1982;2:571–82 [in English]Google Scholar
6Bocheneck, Z, Kukwa, A. An extended approach through the middle cranial fossa to the internal auditory meatus and the cerebellopontine angle. Acta Otolaryngol 1975;80:410–14CrossRefGoogle Scholar
7Kanzaki, J, Kawase, T, Sano, K, Shiobara, R, Toya, S. A modified extended middle cranial fossa approach for acoustic tumors. Arch Otorhinolaryngol 1977;217:119–21Google Scholar
8Kanzaki, J, Shiobara, R, Toya, S. Acoustic Neuroma Surgery. Translabyrinthine-transtentorial approach via the middle cranial fossa. Arch Otorhinolaryngol 1980;229:261–9CrossRefGoogle ScholarPubMed
9Morrison, AW. Experiences with a translabyrinthine-transtentorial approach to the cerebellopontine angle. Technical note. J Neurosurg 1973;38:382–90Google Scholar
10House, WF, Shelton, C. Middle fossa approach for acoustic tumor removal. Otolaryngol Clin North Am 1992;25:347–59CrossRefGoogle ScholarPubMed
11Shelton, C, Brackmann, DE, House, WF, Hitselberger WE. Middle fossa acoustic tumor surgery: results in 106 cases. Laryngoscope 1989;99:405–8CrossRefGoogle ScholarPubMed
12Ulug, T, Ulubil, SA. Management of facial paralysis in temporal bone fractures: a prospective study analyzing 11 operated fractures. Am J Otolaryngol 2005;26:230–8Google Scholar
13Ulug, T, Ulubil, SA. Bilateral traumatic facial paralysis associated with unilateral abducens palsy: a case report. J Laryngol Otol 2005;119:144–7CrossRefGoogle ScholarPubMed
14Ulug, T, Ulubil, SA. Contralateral labyrinthine concussion in temporal bone fractures. J Otolaryngol 2006;35:380–3CrossRefGoogle ScholarPubMed
15Chopra, R, Fergie, N, Mehta, D, Liew, L. The middle cranial fossa approach: an anatomical study. Surg Radiol Anat 2003;24:348–51, 352–3Google Scholar
16Miller, RS, Pensak, ML. The superior petrosal triangle as a constant anatomical landmark for subtemporal middle fossa orientation. Laryngoscope 2003;113:1327–31Google Scholar
17Ulug, T, Ozturk, A, Sahinoglu, K. A multipurpose landmark for skull-base surgery: Henle's spine. J Laryngol Otol 2005;119:856–61Google Scholar
18Lee, HK, Kim, IS, Lee, WS. New method of identifying the internal auditory canal as seen from the middle cranial fossa approach. Ann Otol Rhinol Laryngol 2006;115:457–60Google Scholar
19Todd, NW. Helpful and unhelpful parts of the superior petrosal triangle. Otolaryngol Head Neck Surg 2006;134:966–9CrossRefGoogle ScholarPubMed
20Graham, MD. Surgical exposure of the facial nerve, indications and techniques. J Laryngol Otol 1975;89:557–75Google Scholar
21Meyerhoff, W. Middle cranial fossa approach to the internal auditory canal. Laryngoscope 1979;89:1004–7CrossRefGoogle Scholar
22Fisch, U, Mattox, D. Microsurgery of the Skull Base. Stutgart: Georg Thieme Verlag, 1991Google Scholar
23Fisch, U. Transtemporal surgery of the internal auditory canal: report of 92 cases, technique, indications and results. Adv Otorhinolaryngol 1970;17:203–40Google Scholar
24Garcia Ibanez, E, Garcia Ibanez, JL. Middle fossa vestibular neurectomy: a report of 373 cases. Otolaryngol Head Neck Surg 1980;88:476–90CrossRefGoogle ScholarPubMed
25Kobayashi, T, Nakao, Y. A new method to identify the internal auditory canal during the middle cranial fossa approach: a preliminary report. Tohoku J Exp Med 2000;191:55–8CrossRefGoogle ScholarPubMed
26Wiet, RJ, Lotan, AN, Monsell, EM, Shambaugh, GE Jr.Tumor involvment of the facial nerve. Laryngoscope 1983;93:1301–9Google Scholar
27Rhoton, AL, Tedeschi, H. Microsurgical anatomy of acoustic neuroma. Otolaryngol Clin North Am 1992;25:257–94CrossRefGoogle ScholarPubMed
28Todd, NW. Cochlear implantation via the middle fossa: surgical and electrode array considerations. Cochlear Implants Int 2007;8:1228Google Scholar
29Isaacson, B, Vrabec, JT. The radiographic prevalence of geniculate ganglion dehiscence in normal and congenitally thin temporal bones. Otol Neurotol 2007;28:107–10Google Scholar
30Kartush, JM, Brackmann, DE. Acoustic neuroma update. Otolaryngol Clin North Am 1996;29:377–92Google Scholar
31Kartush, JM, Kemink, JL, Graham, MD. The arcuate eminence: topographic orientation in middle cranial fossa surgery. Ann Otol Rhinol Laryngol 1985;94:25–8Google Scholar
32Seo, Y, Ito, T, Sasaki, T, Nakagawara, J, Nakamura, H. Assessment of the anatomical relationship between the arcuate eminence and superior semicircular canal by computed tomography. Neurol Med Chir 2007;47:335–9, 339–40CrossRefGoogle ScholarPubMed
33Bulsara, KR, Leveque, JC, Gray, L, Fukushima, T, Friedman, AH, Villavicencio, AT. Three-dimensional computed tomographic analysis of the relationship between the arcuate eminence and the superior semicircular canal. Neurosurgery 2006;59 (suppl 1):712Google Scholar