It branches from thevagus nerve(cranial nerve 10) but follows an unusual pathway to reach the larynx.
The paired nerves don’t follow the same symmetrical course.
The RLN supplies motor and sensory function to the voicebox.
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Location and How It Works
There are 12cranial nervesin the human body.
Many of the nerves support function in the face and throat, as does the recurrent laryngeal nerve.
The recurrent laryngeal nerve serves both motor and sensory functions.
It also sends sensory fibers, along with the motor and secretory fibers, to the esophagus and trachea.
Extra branching occurred in both.
Sometimes, the left RLN passes in front of the inferior thyroid artery.
In two-thirds of the cases, it passed behind it.
It’s the opposite frequency with the right RLN.
This is important information when planning surgery, such as athyroid removal.
Injury can occur due to overstretching and other causes.
It can also cause breathing problems, which is calleddyspnea.
This problem is rare, though, with permanent damage occurring in less than 3% of thyroid surgeries.
Surgeons often monitor the RLN during a procedure, using electrodes to continually assess function.
That’s because the paralyzed vocal fold starts out in a somewhat normal position but then atrophies over time.
The airway is often partially obstructed, and the patient may be in respiratory distress.
A condition called biphasic stridor is also possible.
In some cases of bilateral paralysis, breathing problems and/or exertion-related stridor may not be apparent until later.
Tumors
In some cases of cancer, the tumor(s) compresses the recurrent laryngeal nerve.
Or, the cancer’s spread (metastasis) can affect either the left or right RLN.
In some extreme cases, the surgeon may intentionally sever the RLN to remove a tumor.
Other Disease
Infection or inflammation can affect the RLN.
Other options include:
Keep in mind that some people experience permanent damage.
There are two, with anatomical differences leading to a greater risk of injury on the left.
RLN damage following surgery is a common cause of injury.
Surgeries including thyroplasty may be needed to relieve symptoms and repair th recurrent laryngeal nerve.
McGill University.The Unintelligent Design of the Recurrent Laryngeal Nerve.
2020 Sep 4;10(9):670. doi:10.3390/diagnostics10090670
Radiopaedia.Recurrent laryngeal nerve.
2024 Jul 2;111(7):znae143.
2024 Mar;46(3):353-362. doi:10.1007/s00276-023-03293-7
Amer, Khalid.The Recurrent Laryngeal Nerves and the Thoracic Surgeon.
Swonke ML, Shakibai N, Chaaban MR.Medical Malpractice Trends in Thyroidectomies among General Surgeons and Otolaryngologists.OTO Open.
2020 May 13;4(2):2473974X20921141.
2018;14(3):e111-e117.
2017:069-071. doi:10.17352/2455-5282.000051
Children’s Hospital of Philadelphia.Recurrent laryngeal nerve (RLN) reinnervation.
Mount Sinai.Laryngeal nerve damage.
University of California Irvine.Thyroplasty.
