The larynx, also called the voice box, is a funnel-shaped organ located in the throat. It is formed by the hyoid bone and nine cartilages which are connected by muscles and ligaments. The primary functions of the larynx are to protect the trachea, or windpipe, when swallowing and to produce sound.
When a person swallows, a cartilage flap called the epiglottis comes down over the larynx and covers the opening. This directs food and liquids off to the sides and down the esophagus, the pipe which goes between the upper throat, or pharynx, and the stomach. If this did not happen, whatever had been swallowed would go down the windpipe and into the lungs. Between swallows, the epiglottis lifts, allowing air to flow freely.
The larynx contains vocal cords separated by a triangular opening called the glottis through which air flows. When making sounds, the arytenoid muscles twist the arytenoid cartilage. This cartilage can move into as many as 170 different positions. The glottis narrows, controlling the flow of air, which causes the vocal cords to vibrate and create sound. The sounds created would be too quiet to actually hear without the amplification provided by the chest, pharynx, trachea, larynx, nose and mouth.
Voice problems can be caused by a number of disorders within the trachea, but most of them are non-malignant and generally respond to treatment. One common cause is lesions, or abnormal areas of tissue, on the vocal folds. These are often caused by using improper speech methods when speaking, shouting or singing. Polyps, or small tissue growths, can form quickly from excessive coughing or screaming, such as yelling at a ball game. Cysts, fluid-filled sacs, can occur when a gland does not drain properly.
In most cases, these disorders can be treated with rest and voice therapy. In some instances, surgery is required to remove a cyst or polyp which will not respond to therapy alone. Another common complaint is hoarseness or a loss of voice caused by laryngitis, or inflammation of the larynx. There are many causes of laryngitis, such as smoke, noxious fumes, and bacterial or viral infections. The treatment will depend upon the underlying cause.
In some instances, throat cancer can develop in the larynx. The most common cause is smoking and heavy drinking. Treatment involves surgical removal of the cancer followed by some type of nuclear medication. If the tumor is small enough, surgery followed by radiation therapy is usually sufficient. If the cancer has spread to the lymph nodes, treatment will generally require a combination of radiation and chemotherapy. If the tumor is positioned in such a way that part or all of the vocal cords must be removed, artificial implants are available. Voice therapy is generally suggested as part of the recovery process.
Symptoms of throat cancer include hoarseness, coughing, and bloody mucus without any apparent cause. Sometimes a lump will appear or the quality of the voice can change. If these symptoms continue for more than two weeks, it is important to be checked by a medical professional. If caught early, cancer in the larynx can be successfully treated.