History of Spasmodic Dysphonia
The first documented reference to spasmodic dysphonia comes from Ludwig Traube in 1871 (pictured). He described the disorder as a nervous hoarseness and coined the term “spastic dysphonia.” “Spastic” refers to muscles that stay fixed or rigid. “Dysphonia” means a difficulty or abnormality of the voice. Gowers described a functional laryngeal spasm where the cords were brought together too forcibly while speaking and contrasted it to “phonic paralysis,” where the cords could not be brought together while speaking. Critchley followed in 1939 by recognizing the voice pattern as a condition in which the patient sounded as though he were “trying to talk whilst being choked.” In 1952, Bellusi talked about “stuttering” with the vocal cords.
The medical understanding of SD leapt forward in 1968 when Aronson described two different types of the voice disorder: Adductor SD (AdSD) with strained-strangled hoarseness due to hyperadduction of the vocal folds and Abductor SD (AbSD) with intermittent breathy phonation or aphonia (lack of sound). Aronson also described the symptoms as "spasmodic," explaining that they “wax and wane from moment to moment in a spasmodic fashion” rather than maintain a fixed rigidity as the term “spastic” implies. From then on, the condition was known as “spasmodic dysphonia.” In 1981, he identified a tremor apparent in the disorder and noted that it was similar to that in essential tremor, although these two disorders are distinctly different.
Also during the second half of the twentieth century, the theory of a neurological basis for SD grew in popularity following several key developments. Dr. Herbert Dedo first severed the overactive nerve from the hyperfunctional muscles. Nerves are capable of regenerating and, as soon as the severed nerve grew back into its original position in the muscle, the spasmodic voice began again. Jacomb, in 1979, associated SD with Meige Syndrome, which is a combination of blepharospasm and oromandibular dystonia. This led to the collaboration of Doctors Marsden, Fahn, Blitzer, and Brin in reviewing the similarities between SD and other forms of dystonia. In 1985, Blitzer and Brin published a paper, based on electromyography studies, showing that this was not a spastic disease at all, but was rather a focal laryngeal dystonia. The categorization of SD as a brain disorder strengthened the link to the neurology community and widened the treatment and research possibilities.
The medical understanding of SD leapt forward in 1968 when Aronson described two different types of the voice disorder: Adductor SD (AdSD) with strained-strangled hoarseness due to hyperadduction of the vocal folds and Abductor SD (AbSD) with intermittent breathy phonation or aphonia (lack of sound). Aronson also described the symptoms as "spasmodic," explaining that they “wax and wane from moment to moment in a spasmodic fashion” rather than maintain a fixed rigidity as the term “spastic” implies. From then on, the condition was known as “spasmodic dysphonia.” In 1981, he identified a tremor apparent in the disorder and noted that it was similar to that in essential tremor, although these two disorders are distinctly different.
Also during the second half of the twentieth century, the theory of a neurological basis for SD grew in popularity following several key developments. Dr. Herbert Dedo first severed the overactive nerve from the hyperfunctional muscles. Nerves are capable of regenerating and, as soon as the severed nerve grew back into its original position in the muscle, the spasmodic voice began again. Jacomb, in 1979, associated SD with Meige Syndrome, which is a combination of blepharospasm and oromandibular dystonia. This led to the collaboration of Doctors Marsden, Fahn, Blitzer, and Brin in reviewing the similarities between SD and other forms of dystonia. In 1985, Blitzer and Brin published a paper, based on electromyography studies, showing that this was not a spastic disease at all, but was rather a focal laryngeal dystonia. The categorization of SD as a brain disorder strengthened the link to the neurology community and widened the treatment and research possibilities.
Sources:
National Spasmodic Dysphonia Association. (2014). History of SD. Retrieved from http://www.dysphonia.org/history.php
National Spasmodic Dysphonia Association. (2014). History of SD. Retrieved from http://www.dysphonia.org/history.php