gms | German Medical Science

60th Annual Meeting of the German Society of Neurosurgery (DGNC)
Joint Meeting with the Benelux countries and Bulgaria

German Society of Neurosurgery (DGNC)

24 - 27 May 2009, Münster

The endoscopic transmaxillary approach to the orbit: an anatomical study

Meeting Abstract

  • M. Scholz - Neurochirurgische Universitätsklinik, Knappschaftskrankenhaus, Ruhr-Universität Bochum
  • S. Schultheiss - Neurochirurgische Universitätsklinik, Knappschaftskrankenhaus, Ruhr-Universität Bochum
  • P. Spangenberg - Neurochirurgische Universitätsklinik, Knappschaftskrankenhaus, Ruhr-Universität Bochum
  • S. Lücke - Neurochirurgische Universitätsklinik, Knappschaftskrankenhaus, Ruhr-Universität Bochum
  • A. Harders - Neurochirurgische Universitätsklinik, Knappschaftskrankenhaus, Ruhr-Universität Bochum

Deutsche Gesellschaft für Neurochirurgie. 60. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC), Joint Meeting mit den Benelux-Ländern und Bulgarien. Münster, 24.-27.05.2009. Düsseldorf: German Medical Science GMS Publishing House; 2009. DocDI.04-06

DOI: 10.3205/09dgnc132, URN: urn:nbn:de:0183-09dgnc1325

Published: May 20, 2009

© 2009 Scholz et al.
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Outline

Text

Objective: The aim of this study was to approve the feasibility of an endoscopic transmaxillary approach to the orbit in human cadaveric heads, using a pituitary endoscope. During the last years, alternative endoscopic approaches to the clivus or anterior skull base have been developed; endoscopic pituitary surgery has become common. The endoscopic transmaxillary approach to the orbit for neurosurgical purposes has not been described to our knowledge.

Methods: A transmaxillary approach to the orbit was performed using a Storz Hopkins II pituitary endoscope with a 0° and 30°angled optic in nine human cadaveric heads (six of them vessel-injected with colour). Via a sublabial route, the maxillary sinus was opened through the canine fossa; the orbital floor was removed. Inferior intraconal structures were dissected and anatomical relationships were measured in situ. All procedures were recorded with a DVD recorder system. Images were extracted digitally using the Hypersnap Software.

Results: This approach allows a dissection of the inferior intraconal structures without injury to the infraorbital nerve and artery and the inferior rectus muscle. Exposure was possible from the medial and lateral rectus muscle to the optic nerve in all cases. The inferior rectus muscle was mobilised, so removal of orbital fat and dissection of the ophthalmic artery and ciliary nerves superiorly were possible. The optic nerve was dissectible averaged 14 mm from the eyeball. A dissection of the structures superior to the optic nerve was not possible because ciliary nerves and ophthalmic artery were obstructing the access.

A 30° angled optic enables a good overview, a 0° optic was usually not useful for this approach. The window in the canine fossa averaged 14x9 mm, in the orbital floor medial of the infraorbital nerve 10x17 mm. An access extended lateral to the infraorbital nerve did not prove essential for dissection of the orbit. Visualization and especially overview were better compared to microscopic techniques, as documented by a series of images.

Conclusions: The endoscopic transmaxillary approach to the orbit was possible in all cases. Orbital fat between the inferior intraconal structures could be removed suggesting resection of an orbital lesion (e.g. cavernoma) in the lower part of the orbit to be possible in clinical cases.