Frontal recess anatomy study by endoscopic dissection in cadavers.

Area of Science:

• Otolaryngology
• Endoscopic Sinus Surgery
• Anatomical Studies

Background:

• The frontal sinus ostium is often obscured by surrounding anatomical structures.
• Accurate identification is crucial for effective endoscopic sinus surgery.

Purpose of the Study:

• To identify and describe frontal recess anatomy hindering endoscopic frontal sinus ostium recognition.
• To determine which structures impede ostium visualization during endoscopic dissection.

Main Methods:

• Prospective endoscopic dissections of 32 cadavers (59 sides).
• Resection of the uncinate process's lower portion while preserving its upper insertion.
• Evaluation of structures requiring removal for ostium visualization.

Main Results:

• Frontal sinus ostium visualization was achieved in only 18.64% of nasal cavities post-uncinate process resection.
• The uncinate process (terminal recess) was the primary obstruction in 76.27% of cases.
• Ethmoid bulla (16.95%) and agger nasi cells (6.78%) were secondary obstructions.

Conclusions:

• The uncinate process is the main anatomical barrier to frontal sinus ostium identification.
• Surgical modification of the uncinate process is often required for ostium access.
• Understanding these anatomical variations is key for successful endoscopic frontal sinus surgery.