The Human Laryngeal Innervation Revisited—The Role of the Neural Connections

Abstract

In spite that vascular inconvenients or immunological rejections have been solved in relation with larynx transplant, a successful functional reinnervation has not been achieved. Some studies have suggested that laryngeal nerve connection may contain motor fibers, which could explain unexpected evoked responses in electromyographic studies or the different positions adopted of the vocal folds after similar nerve lesions. Ten patients with unexpected evoked responses after laryngeal nerve stimulation were selected. All the patients underwent a total laryngectomy due to oncological causes. In every case, laryngeal nerve connections were observed. All of them were morphologic and histologic processed for choline-acetyltransferase immunohistochemistry. The presence of motor axons in the nerve connections has been demonstrated, which would explain that the motor innervation to the laryngeal muscles could be dual through these variable connections. This also would justify the difficulty of carrying out laryngeal nerve reinnervation procedures. Anat Rec, 2018. © 2018 Wiley Periodicals, Inc.

Evaluation of the Cricothyroid Muscle Innervation Pattern Through Intraoperative Electromyography

“…The high latency time indicate contraction by innervation, other than the contralateral CTM twitching although the amplitude of the CEB-SLN stimulation was significantly low. Martin-Oviedo et al [34] have recently detected twitching in the contralateral CTM, TAM, and arytenoid muscles with EBSLN stimulation, which was attributed to the nerve connections from the deep arytenoid plexus by the authors. Anatomy studies report the incidence of arytenoid plexus as 28-100%.…”

Cranial Nerves: Phylogeny and Ontogeny

“…The morphology and clinical relevance volume includes gross anatomical and/or surgical approaches to cranial nerves III, IV, and VI (Apaydin et al, ); V including neuralgia (Ruiz‐Juretschke et al, ) and mandibular patterning (Sakaguchi et al, ); VII intracranial (Aristegui et al, ) and extracranial (Martinez Pascual et al, ); XI extracranial course (Sakamoto, ) and carotid sinus nerve (Porzionato et al, ); X focused on larynx innervation (Martin‐Oviedo et al, ); XI on topographical surgical relevance (Johal et al, ), and XII on its branching pattern (Sakamoto, ).…”

A Toast to the Cranial Nerves

“…Examples of all this morphological and functional complexity, with obvious consequences for the clinical aspects of the cranial nerves, are provided by the papers in this second volume of the Special Issue Cranial Nerves of The Anatomical Record . The papers provide perspectives about the surgical anatomy of the orbit, with special emphasis on oculomotor, trochlear, and abducens nerves (Apaydin et al, ), the importance of the variability of the facial nerve to other surrounding structures within the petrous portion of the temporal bone (Arístegui et al, ), as well as through the extra‐cranial course (Martínez Pascual et al, ), the vascular relationships of the trigeminal nerve in patients with classic trigeminal neuralgia (Ruiz‐Juretschke et al, ), the extra‐cranial course and branching pattern of the glossopharyngeal nerve (Sakamoto, ), the spatial relationships of the hypoglossal nerve with the tongue and associated muscles (Sakamoto, ), the clinical implications of the anatomy and function of the carotid sinus nerve (originated from the glossopharyngeal nerve, Porzionato et al, ), the innervation of the masticatory muscles (Akita et al, ), the morphology, embryology, surgical anatomy, and clinical manifestations of the accessory nerve (Johal et al, ), and the innervation of human larynx, describing the difficulty of carrying out laryngeal nerve reinnervation procedures (Martín‐Oviedo et al, ).…”