Sphenoidotomy is defined as creating an opening into the anterior, or front, wall of the sphenoid sinus. The sphenoid sinus is bordered above by the brain and pituitary gland and laterally, or on its sides, by the optic nerves and the major blood to the anterior brain. Therefore, all surgical approaches to this sinus have evolved from various procedures that are performed through the nose or involve the nasal cavity.
The most common approach today is through the nasal cavity, using an optical telescope for visualization of the posterior nose and the sphenoid sinus. This same approach can be performed utilizing an operating microscope or headlight. A second approach is through the nasal septum which directs the surgeon to the midline of the sphenoid sinuses. This transeptal approach is frequently used to visualize and remove tumors of the pituitary gland. The third form of sphenoidotomy is to approach the sphenoid sinus through the maxillary and ethmoid sinuses.
This transantral-ethmoidectomy procedure required partial removal of the anterior wall of the maxillary sinus to visualize the ethmoid and sphenoid sinuses. Irrespective of the approach, sphenoidotomy is potentially problematic given the close proximity of this sinus to the eye and central nervous system. No matter the approach, the ethmoid sinus is the key or essential element in the surgical treatment of sinusitis.
Illustration of sagittal (midline) section through right sphenoid sinus. This drawing emphasizes the important neurologic and vascular structures which border the outer wall of the sphenoid sinus. As infectious or neoplastic disease progresses within the sphenoid sinus, patients can develop symptoms referable to any of illustrated nerves or vessels. For example, tumors or infection encroaching upon the maxillary nerve would give rise to mid-face pain. Disease involving the optic nerve would initially present with partial loss of temporal vision (peripheral or lateral vision) and progress to total blindness (modified from Rice DH, Schaefer SD. Endoscopic Paranasal Sinus Surgery, 3rd Ed. Lippincott; Philadelphia. 2003.
MRI of patient with acute left sphenoid sinusitis refractive to antibiotic therapy. This patient complained of intense mid face and vertex pain. As is seen in this patient, the sphenoid sinus may extend beyond the body of the sphenoid bone to pneumatize or involve the adjacent regions. In this case, a lateral recess has been formed within the greater wing of the sphenoid sinus. This image illustrates the close proximity of important brain, eye and blood vessels to the sphenoid sinus.