3D Models Related Images

Upper Subtotal Maxillotomy: Exposure Obtained With Mobilization of the Upper part of the Maxilla

Surgical Correlation

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A, This approach uses paranasal, lower conjunctival, transverse temporal, and preauricular incisions. In the usual approach, the cheek flap is elevated as a single layer using subperiosteal dissection. In this dissection, the layers of the cheek flap were dissected separately to illustrate the structures in the flap. The facial muscles and branches of the facial nerve are exposed. The parotid gland has been removed. The frontal branch of the facial nerve crosses the middle portion of the zygomatic arch. If facial nerve branches are transected in the approach, they are tagged in preparation for reapproximation at closure. B, A hemicoronal scalp incision and reflection of the temporalis muscle exposes the lateral orbital rim. The cheek flap containing the facial muscles, branches of the facial nerve, parotid gland, and masseter muscle have been reflected inferiorly to the level of the maxillary attachment of the buccinator muscle. The orbital, maxillary, and zygomatic osteotomies have been completed and the lower half of the orbital rim, the anterior, medial, and lateral walls of the maxillary sinus, and the zygomatic arch have been reflected. The lower horizontal cut, located at the Le Fort I level, extends above the apical dental roots and hard palate and along the inferior nasal meatus medially. The maxillotomy, at this stage, does not include the posterior maxillary wall or cross the greater and lesser palatine canals. The lateral nasal wall was included with the maxillotomy to expose the nasal cavity. The infraorbital nerve, which crosses the orbital floor, may be preserved for reconstruction. C, The posterior wall of the maxillary sinus has been removed to expose the pterygopalatine fossa and the palatine nerves and arteries. The base of the coronoid process was divided, and the temporalis reflected downward to expose the lateral pterygoid muscle and maxillary artery in the infratemporal fossa. D, A frontotemporal bone flap has been elevated, the dura covering the frontal and temporal lobes and lateral wall of the cavernous sinus have been opened, and the temporal lobe has been elevated. The pterygoid muscles, the pterygoid process and plates, and the part of the middle fossa floor formed by the greater sphenoid wing have been removed to expose the nerves passing through the foramina rotundum and ovale. The eustachian tube is exposed behind the mandibular nerve and the middle meningeal artery. E, Magnified view of the cavernous sinus, superior orbital fissure, and orbit. The oculomotor, trochlear, and ophthalmic nerves course through the lateral wall of the cavernous sinus. The ophthalmic nerve sends its branches along the upper part of the orbit. The maxillary nerve exits the foramen rotundum and passes through the pterygopalatine fossa, where it gives rise to the infraorbital nerve that courses along the floor of the orbit. The mandibular nerve passes through the foramen ovale and sends its branches through the infratemporal fossa. The vidian nerve passes forward in the vidian canal below the maxillary nerve to join the pterygopalatine ganglion in the pterygopalatine fossa. F, Enlarged view of the orbital exposure. The lacrimal gland sits on the superolateral margin of the globe. The lacrimal nerve courses above the lateral rectus muscle. The inferior oblique muscle passes below the attachment of the inferior rectus muscle and upward between the globe and lateral rectus muscle to insert on the globe near the tendon of insertion of the superior oblique muscle. (Images courtesy of AL Rhoton, Jr.)

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