A Laryngocele is an enlargement or dilation of the sacculous or appendix form the vestige of the Ventricle of Morgagne. It is often in horn players or glass blowers. It often presents with horseness, dyspnea, or a neck mass. Some texts site the existence of an internal laryngocele, however, that is probably best termed a Saccular Cyst and is best resected endoscopically. When the saccule actually herniates through the foramen in the thyrohyoid membrane (where the internal branch of the Superior Laryngeal Nerve enters). It will dilate out with a Reverse Mueller’s Maneuver (not with a Valsalva—Positive Pulmonary pressure against a closed glottis) as the diverticulum is supraglottic. This is sometimes termed “Furstenburg’s sign of the neck.
Diagnosis is primarily clinical and is best confirmed with a contrasted CT scan of the neck. If it unfortunately becomes infected it is then termed a Laryngopyocele. Treatment is meticulous excision via external approach. You will have to make an inferiorly based perichondrial flap and resect some of the lateral thyroid cartilage. The Superior Laryngeal Nerve needs to be identified and protected.
An internal Laryngocele might be better termed a Saccular Cyst and is probably best managed with an endoscopic excision with the Lindholm Laryngoscope, blunt dissection, and cautery.