Laryngocele refers to a congenital anomalous air sac which communicates with the cavity of the larynx which bulges outward. People who conduct forced expiration exert extreme pressure on the larynx which leads to dilation of the laryngeal ventricle. It can also be noticed in people who have obstructive airway disease.
This is a mild tumor which was first described by Virchow in 1863.
Laryngocele can be the result of abnormally large saccule. Saccule is the appendix of the laryngeal ventricle. This abnormally large saccule may extend over the level of the thyroid cartilage. These structures are connected with the laryngeal lumen and it is filled with air. This condition is more common in adults.
Picture 1 – Laryngocele Picture
The tumor may be congenital in nature or acquired.
The tumor can be of three types:
It occurs in the interior of the laryngeal cavity. It extends into the paraglottic region of the false vocal cord and aryepiglottic fold.
It is a condition in which both internal and external components of Laryngocele exist together.
This type extends and dissects superiorly through the thyroid membrane. It is closely connected to the superior laryngeal nerve. It often manifests itself as lateral neck mass.
The saccule is outlined by pseudo stratified ciliated columnar epithelium. It also contains many numerous mucous glands in the submucosal areolar tissue. These glandular secretions keep the vocal cord moist and lubricated. Saccule is thus known as the oil can of the larynx.
The symptoms of Laryngocele are as follows:
- Foreign-body sensation in the throat.
- Hoarseness of voice.
- Large internal laryngoceles, which may lead to airway obstruction.
- Presence of external laryngocele with a neck mass that is located close to the thyroidal membrane.
These tumors can be diagnosed with the help of flexible fibroptic laryngoscopy, endoscopic examination and videostroboscopy and CT scan of the neck with IV contrast. Such lumps, in an old patient, prompt doctors to thoroughly search for the laryngeal malignancy. Indirect laryngoscopy can be diagnosed. They appear as submucosal mass in the region of false vocal cord. If fibre optic laryngoscope is used, the masses will appear enlarged during a valsalva maneuver. In case of pure external laryngocele, the edolaryngeal examination will be normal. If combined laryngocele is present as a neck mass, compression will let on a hissing sound as the air escapes from it into the larynx. Radiological examination is another method. A plain X-ray soft tissue neck present an air filled sac which protrudes from the soft tissues of neck. When X-ray is repeated on Valsalva maneuver the size of the mass will be an enlargement.
Internal laryngoceles can be removed through endoscopy. External and combined internal and external laryngoceles can be managed through an open approach.
Various kinds of surgical approaches have been opted for in the treatment of different types of Laryngoceles.
External lateral neck approach is favored by surgeons as it gives maximum exposure to the problem, has very low chances of fatal consequences and minimum risks of recurrence. To treat internal laryngoceles, a small part of the thyroid cartilage may have to be removed to allow maximum exposure. External and combined laryngoceles can be dissected through the thyroid membrane and cartilage is not removed.
Surgeons make a horizontal cut over the natural skin crease just above the thyroid membrane. The mass lies over this area, thus it is not difficult to identify the membrane area. Skin flaps are taken apart in the subplatysmal plane. The bulging strap muscles are transected to give a better exposure to the mass. The carotid sheath is pushed posteriorly. The ansa cervicalis nerve which is attached to the laryngocele is removed and is dissected out. After the lump is removed, the void is covered with sutures.
In this operative process, the larynx is opened in the midline. A submucosal or transmucosal method is used to remove the small internal laryngoceles. The major risk of this procedure is anterior commisure blunting and subglottic stenosis.
This is opted for in case of small internal laryngoceles. The procedure starts with exposure of the larynx and suspension of the patient for direct laryngoscopy. The lesion is inspected thoroughly. The cysts are decompressed from inside and removed totally. Recurrence however is a possibility in this method. The incision is made over the middle portion of the lesion with blunt instruments along with the help of laser. The surgery is done carefully so as to not injure the superior vocal fold. At the end of the surgery, the false vocal cord is trimmed.
Complications can arise if the superior laryngeal nerve is not identified carefully and not preserved. This is because this nerve is very closely connected to the mass. The complications that can occur are varied in nature. The complications associated to surgical procedures related to this condition include:
- Airway obstruction due to mucosal oedema.
- Laryngo cutaneous fistula
- Subcutaneous emphysema.
- Injury to superior or internal laryngeal nerve.