Spasmodic dysphonia is a voice disorder in which the vocal cords close involuntarily, wherein the voice goes into periods of spasm.
Because there is no abnormality in the appearance of the vocal cords, many patients are diagnosed as normal or their complaint is considered "psychogenic," and proper treatment is delayed. The main treatments currently in use are described in the following.
Botulinum toxin (BT) injection
This is the most common treatment and is used worldwide. BT injection temporarily weakens the vocal cord muscle, such that it cannot become spasmodic, and thus allows the voice to return to its original state. The injection can be administered in the out-patient unit, but its effectiveness is limited and repeat injection every 3–4 months may be necessary.
Thyoroarytenoid muscle myectomy
In this procedure, the vocal cord muscle (thyroid arytenoid muscle) is surgically removed. Hospitalization is required because the operation is performed under general anesthesia, but neck incision is unnecessary. A breathy voice will occur during the first 1- 3 months after surgery. But you can expect the voice to gradually improve back to .normal
The video on the left is before surgery (tyroarytenoid muscle myectomy), and the one on the right is seven months after the surgery. Postoperative voice is normal without any symptoms of SD
Thyroplasty type II
An incision of about 3 cm is made under local anesthesia. The thyroid cartilage is separated horizontally to avoid damage on the vocal fold. As the cartilage is separated gradually, the patient's strangled voice will improve. Depending on the patient’s voice quality, the vocal cords are optimally adjusted and their position is fixed with a titanium bridge. Usually, a 2-3mm separation is good.
Video during surgery: After separation of voice box cartilage, the patient's voice improved and was relieved of any spasmodic symptoms.
Abductor spasmodic dysphonia
This type is only 3% of spasmodic dysphonia. The vocal cord opens involuntarily causing the patient's voice to become breathy. The video below is a sample voice.
Symptoms are relieved by BT injection in the muscle that opens the vocal cords.