It has previously been shown that identification of the recurrent laryngeal nerves reduces the risk of injury to the nerves during thyroid surgery. To facilitate identification and to test the conductivity of the recurrent nerves we have used electrical stimulation of the nerves and simultaneous recording of the vocal cord movements with two different endolaryngeal devices. The experience gained with these devices indicates that it is possible to reduce the frequency of injury to the nerves, and the method accelerates the progress of the operation, especially in cancer surgery and repeat operations.
The principle of sonotubometry for recording the opening of the Eustachian tube is based on the assumption that this opening increases the sound transmission from the nasopharynx to the external ear canal. However, the clinical validity of the method remains to be documented. In the present study the results in 37 normal ears were compared with those of 11 ears which showed signs of Eustachian tube dysfunction. In these glue was found in the middle ear at a subsequent myringotomy. In 13 of the subjects a comparison was made of the signals picked up from the ear canal and from the contralateral nostril. It was concluded that the interpretation of the signals from the ear canal is very complicated. They may be due to an opening of the Eustachian tube, but they may also be caused by a change of the acoustic conditions in the nasopharynx during the swallowing procedure. Despite the fact that this test principle in theory is ideal, much research seems to be required before the clinical value of the method can be confirmed.
A method for identification and functional recording of the recurrent nerve during neck operations is described. The basic principle implicates electrical stimulation of the recurrent nerve causing adduction of the vocal cord registered by means of a balloon placed between the vocal cords. Three different recording methods have been tested in animal experiments and during 26 neck operations on patients. The most simple method employed is recommended as a routine procedure, likely to reduce surgical damage to the recurrent nerve.
Grossly abnormal auditory brain stem responses (ABR) and abnormally high stapedius reflex thresholds were found in 2 pairs of siblings, not akin. Pure tone audiometry showed moderate to moderately severe hearing impairment in all 4 subjects, but neither the ABR findings nor the stapedius reflex thresholds were compatible with pure cochlear lesions. In all the cases the benefit from using hearing aids was conspicuously poor, and the development of oral language markedly retarded, one pair of siblings being essentially incapable of oral--aural communication. A cousin to one of the pairs of siblings showed similar but less pronounced symptoms and signs. Intelligence was judged to be normal in all 5 individuals and neurologic examination did not reveal CNS abnormalities besides the hearing impairment. We assume dysfunction of the brain stem auditory pathways to be the main cause of the speech retardation in the 2 pairs of siblings and the abnormality to be hereditary in nature.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.