What is hiatus semilunaris superior?
The hiatus semilunaris superior is a “crescent-shaped cleft between the ethmoid bulla and the middle turbinate. ‘? It too is a two-dimensional area and it leads to the suprabullar and retrobullar recesses (the sinus lateralis of Grunwald) and ultimately to the frontal recess (Figure 1B).
What is the hiatus semilunaris?
The hiatus semilunaris is a semicircular shaped opening located on the lateral wall of the nasal cavity. It is a component of the ostiomeatal complex and serves as the opening for the frontal and maxillary sinuses and the anterior ethmoid air cells.
Which sinus drains into the hiatus semilunaris?
maxillary sinus
The hiatus semilunaris (or semilunar hiatus) is a crescent-shaped groove in the lateral wall of the nasal cavity just inferior to the ethmoidal bulla. It is the location of the openings for the frontal sinus, maxillary sinus, and anterior ethmoidal sinus.
Which sinuses open in posterior hiatus semilunaris?
What is an ethmoid bulla?
The ethmoid bulla is the largest anterior ethmoid air cell. It is also one of the most consistent air cells in the middle meatus and is therefore a reliable anatomic landmark (Fig. 2.13). It often lacks a posterior wall, which is why it is not called a cell but rather a bony lamella with a large airspace behind it.
How maxillary hiatus is reduced?
In the articulated skull this aperture is much reduced in size by the following bones: the uncinate process of the ethmoid above, the ethmoidal process of the inferior nasal concha below, the vertical part of the palatine behind, and a small part of the lacrimal above and in front; the sinus communicates with the …
What is the function of paranasal sinuses?
They are centered on the nasal cavity and have various functions, including lightening the weight of the head, humidifying and heating inhaled air, increasing the resonance of speech, and serving as a crumple zone to protect vital structures in the event of facial trauma.
Where is the sinus ostia?
The ostium of the maxillary sinus is on the highest part of the medial wall of the sinus and is therefore poorly placed from the point of view of free drainage; in addition it does not open directly into the nasal fossa but into the narrow ethmoidal infundibulum, inflammation of which can further interfere with …
Is ethmoid bulla a bone?
What drains through Ethmoidal Bulla?
The middle ethmoid air cells drain into the ethmoidal bulla. The maxillary sinus also drains into the semilunar hiatus here, posteriorly. In the inferior nasal meatus, the pin is in the opening of the nasolacrimal duct, draining the lacrimal sac near the eye into the nasal cavity.