Can Middle Turbinates Be Palpated

Fig. 5.72 s Sinusotomy, type I. t Note the position of the septal branch of the sphenopalatine artery. u A line diagram to illustrate the size and position of a sphenoidotomy: type I, the dark circle; type II, the dark green vertical rectangle; type III, the dark green horizontal rectangle. The sphenoid and the pale green box that represents a posterior ethmoid air cell are joined. The sphenoid can be opened more extensively but requires ligation of the sphenopalatine artery and an exact knowledge of the position of the carotid and optic nerves.

Ethmoid Cells And Optic Nerve Sphenopalatine Artery

u t u cells and avoid making a tunnel. Beware that in some patients the next partition may be the skull base. If you are unhappy about visibility or the anatomy, it is best to find the sphenoid sinus first before venturing into uncharted waters. Even if you think you know where the sphenoid sinus is, do not be tempted to enter it through the posterior ethmoid complex as this is potentially dangerous. Always find the sphenoid sinus transnasally first if you intend opening up all the posterior ethmoid sinuses.

It is important to have landmarks by which to orientate yourself and to keep back with the endoscope so as to keep these in view. Our preferred strategy is to use the following landmarks to avoid traversing the boundaries of the paranasal sinuses: • Check the CT scan to see that there is no Onodi cell as the optic nerve can sometimes be dehiscent in its lateral wall. Look at the posterior coronal CT slices of the maxillary sinus and look at the height from the roof of the maxillary sinus to the roof of the skull base. Sometimes this can be spacious but sometimes it is small and it will give the operator an idea of the extent of the posterior ethmoidal air cells.

• The roof of the sphenoid sinus is a useful landmark as the posterior ethmoid sinuses are not lower than it, so that if the operator stays in a plane that is lower than the roof of the sphenoid sinus, they are unlikely to traverse the skull base. Often the ethmoid sinuses will extend above this level, but when the posterior ethmoid sinuses have been opened to the level of the roof of the sphenoid sinus these are often apparent and can easily be palpated and opened.

• The posterior ethmoid sinuses that lie medial to the medial wall of the maxillary sinus in a sagittal plane can be removed without concern that the optic nerve or orbit will be damaged.

The sphenoid sinus can safely be found by staying adjacent to the vomer. It lies approximately 1.0-1.5 cm above the bridge or "shoulder" of the posterior choana. Often the bulk of the middle turbinate restricts access to this area and it may be necessary to gently displace the middle turbinate with the side of a Freer's elevator in order to be able to visualize the sphenoethmoid recess. This is easier after an anterior ethmoidectomy

Punch For Sinusotomy
Fig. 5.73 a After completion of the transnasal sphenoid sinusotomy, the cavity of the posterior ethmoids is inspected. b How do you know whether it is safe to go further back to

and when the basal lamella has been entered just above its inferior horizontal connection to the post-eroinferior edge of the middle turbinate. Occasionally a bubble of air will be seen coming from the sphenoid ostium that is positioned much higher in the sphenoethmoid recess. The anterior wall of the sphenoid sinus is so thin that if a straight sucker (diameter 2-3 mm) is walked up the anterior wall of the sphenoid bone from the posterior choana then at 1.01.2 cm the sucker will enter the sinus with moderate pressure. It is wise to stay next to the vomer as to go more laterally runs the risk of damaging the structures in the lateral wall of the sphenoid sinus.

Once you have identified the sphenoid sinus, its anterior wall can be removed up to the skull base. It is wise not to open more than one bite inferiorly unless there is a good reason because of the septal branch of the sphenopalatine artery. Having established the level of the skull base below which it is safe to operate, you can then easily make a window between the superior and middle turbinates that will allow you to check where you are when you return to the posterior sinuses.

Now you can return to the posterior ethmoid sinuses, and after checking that there is a connection through the superior meatus, you can remove more cells that are medial and inferior toward the sphenoid sinus (Fig. 5.73a, b). Doing this creates more space in the posterior complex. The next step is to join the posterior ethmoid sinuses to the sphenoid sinus (Fig. 5.74 a, b). This can safely be done by placing an instrument at the most posterosuperior aspect and then moving it vertically downward and then medially, pointing it toward the sphenoid sinus. With this maneuver the posterior ethmoid and sphenoid sinuses

Sphenoid Posterior

_ b open the sphenoid sinus more? (See Fig. 5.74a, b and Fig. 5.75 a-j for the answer.)

_ b open the sphenoid sinus more? (See Fig. 5.74a, b and Fig. 5.75 a-j for the answer.)

can be joined safely (Fig. 5.75 a-j). It is important to identify the level of the roof of the sphenoid sinus before opening any ethmoidal air cells superiorly, in order to avoid traversing the skull base (Fig. 5.76a-d). It is vital to preserve the superior turbinate at all costs because it is valuable olfactory epithelium. The remaining posterior ethmoid sinuses can be cleaned; a curved sucker is useful to palpate for space behind any partitions to help define the extent of the remaining air cells. A Hajek-Kofler punch is excellent for removing these bony remnants.

If the CT scan shows a "black halo" of air at the periphery of the posterior ethmoidal air cells, this will be helpful because when they are opened the clear mucosa lining the skull base will be seen. If there is a "white out" then care will be needed to ensure that you stay below the level of the roof of the sphenoid sinus. Very rarely, the anterior wall of the sinus is thicker, with hyperostosis secondary to chronic infection, or the sinus is hypoplastic and it will not be possible to enter it. This should be visible on the CT scan preoperatively.

It is best to limit the use of powered instrumentation in the sphenoid sinus unless visibility is good. If such an instrument is used, then the mouth of it should be pointed medially to avoid the risk of damaging any lateral structure. 7, 8

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  • giordano
    Can middle turbinates be palpated?
    8 years ago
  • Andrea
    Can the anterior middle turbinate be removed more than once?
    8 months ago

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