Lynch vs transcaruncular approach: optimizing access to the lateral frontal sinus

Area of Science:

• Otolaryngology
• Endoscopic Sinus Surgery
• Surgical Anatomy

Background:

• Frontal sinus visualization and instrumentation can be challenging with standard endoscopic techniques like the Draf III or modified endoscopic Lothrop procedure (MELP).
• External incisions may be necessary to augment surgical exposure in the frontal sinus.

Purpose of the Study:

• To compare the extent of lateral frontal sinus access achieved using MELP alone versus MELP combined with adjunctive transcaruncular or transcutaneous Lynch incisions.

Main Methods:

• CT scanning of 12 cadaveric heads to assess frontal sinus anatomy.
• Dissection of 8 cadaveric heads (16 sides) performing MELP with bilateral transcaruncular and Lynch incisions.
• Measurement of visualized frontal sinus area under image guidance using 0-degree and 30-degree endoscopes with different suction types.

Main Results:

• MELP alone provided limited access (41.6-48.9%).
• Adjunctive transcaruncular approach showed moderate improvement (47.1-51.6%).
• The transcutaneous Lynch incision yielded the greatest access, especially with a 30-degree endoscope (88.7-91.8%).

Conclusions:

• Adjunctive external approaches, particularly the Lynch incision, significantly enhance visualization and instrumentation of the frontal sinus when used with MELP.
• These techniques can overcome limitations of purely endoscopic approaches for complex frontal sinus cases.