Galen's "anastomosis" revisited.

Area of Science:

• Anatomy
• Laryngeal Innervation
• Nerve Morphology

Background:

• The laryngeal innervation pathway is complex, involving the internal laryngeal nerve (ILN) and recurrent laryngeal nerve (RLN).
• A direct connection, historically termed Galen's Anastomosis (GA), exists between the dorsal branches of the ILN and RLN.

Purpose of the Study:

• To investigate the incidence and morphometric contribution of Galen's Anastomosis (GA) in laryngeal innervation.
• To propose a more accurate terminology for this neural connection.

Main Methods:

• Micro-dissection of 50 adult laryngeal specimens.
• Measurement of the diameters of the ILN and RLN after muscular branch division.
• Literature review to calculate weighted mean incidence of GA.

Main Results:

• The incidence of GA was found to be 81% in the dissected specimens.
• The average diameter of the ILN contributing to GA was significantly larger than that of the RLN.
• The weighted mean incidence from literature (77.3%) supported the current findings.

Conclusions:

• The internal laryngeal nerve (ILN) appears to provide a greater morphometric contribution to the connection between the ILN and RLN.
• The term "communicating branch" is proposed as a more accurate descriptor than "Galen's Anastomosis" for this neural linkage.