The Ethmomaxillary Sinus-A False Duplicate Maxillary Sinus

Area of Science:

• Otolaryngology
• Anatomy
• Surgical Navigation

Background:

• Functional endoscopic sinus surgery (FESS) relies on precise anatomical understanding.
• Ethmoid air cells exhibit predictable migratory patterns.
• Variations in ethmoid air cell anatomy can complicate surgical approaches.

Purpose of the Study:

• To define ethmomaxillary sinuses (EMSs) and differentiate them from other anatomical variations.
• To highlight the clinical significance of EMSs in endoscopic sinus surgery.
• To emphasize the need for detailed pre-surgical anatomical assessment.

Main Methods:

• Review of anatomical literature and imaging studies.
• Description of EMSs and their relationship to surrounding sinuses (maxillary, sphenoid).
• Differentiation of EMSs from Haller's cells, Sieur's cells, and Onodi cells.

Main Results:

• Ethmomaxillary sinuses (EMSs) are posterior ethmoid air cells extending into the maxillary sinus, draining into the superior meatus.
• EMSs occur in 0.68% to 16.48% of cases and can be mistaken for other anatomical structures.
• Zuckerkandl's false duplicate maxillary sinus involves an EMS draining separately into the superior meatus.

Conclusions:

• Accurate pre-operative identification of EMSs is essential for safe FESS.
• Distinguishing EMSs from intrasinus septa prevents surgical misinterpretations.
• Detailed anatomical evaluation is paramount before any endoscopic nasal and sinus procedures.