New discovery and short-term effect analysis of tensor tympani muscle tenotomy for Meniere's disease under otoscope / 中华耳鼻咽喉头颈外科杂志

Objective: To explore the feasibility and short-term effect of tensor tympani muscle Tenotomy in the treatment of Meniere's disease under otoscope. The possible pathogenesis was discussed and our views were put forward. Methods: The clinical data of 9 cases of Meniere's disease treated by otoscopic Tenotomy were analyzed retrospectively, including 2 males, 7 females, 5 right ones, 2 left ones and 2 bilateral ones. The average age was (56.33± 10.56) years, ranging from 38 to 75 years. We evaluated intraoperative findings and short-term postoperative efficacy, respectively evaluated postoperative aural fullness, tinnitus and hearing recovery, and evaluated postoperative vertigo attack in a short time. Results: Nine patients were completed the operation under general anaesthesia and otoscopy, and no serious complications occurred. We found new pathological changes in tympanic cavity in some cases during operation. There were rupture of round window membrane in 1 case, severe fibrous hyperplasia near the round window membrane and vestibular window and adhesion with ossicular chain in 1 case, fibrous cord and membranous hyperplasia near vestibular window and round window membrane in 1 case, fibrous hyperplasia and adhesion near the round window membrane in 2 cases, membranous hyperplasia and adhesion around vestibular window in 1 case. No fibrous hyperplasia was found in 3 cases in the tympanic cavity. The round window membrane can be exposed in 4 cases and failed in 5 cases. After 3 months of follow-up, we found that we found that 5/5 cases of aural fullness disappeared, 2/2 cases of earache disappeared, 3/8 cases of tinnitus improved, 5/8 cases presented with improvement and no aggravation, 3/3 cases of hearing allergy improved, 4/9 cases of hearing improved, and 5/9 cases showed no improvement or decrease. 9 patients were followed up for 3 months, of whom 8 patients had no vertigo, one patient suffered from vertigo twice within 3 months after operation, and the patient suffered from rupture of round window membrane. Conclusions: Endoscopic Tenotomy for Meniere's disease has obvious curative effect and quick recovery after operation. During the operation, we find that most of Meniere's patients have fibrous cord hyperplasia near the inner ear window membrane, which may be the pathological manifestation after repeated rupture and repair of the inner ear window membrane. The vertigo of Meniere's disease may be related to the destruction and repair of inner ear membrane structure caused by improper contraction or spasm of tympanic tensor muscle.

Phylogenic Oto-stomatognathic Connection of the Mammalian Jaw: A Novel Hypothesis for Tensor Tympani Muscle and TMD-related Otologic Symptoms / 체질인류학회지

Otologic complaints, including otalgia, tinnitus, vertigo, and hearing loss, are known to be related to temporomandibular disorders (TMDs). There have been several hypotheses regarding the clinical correlation between otologic complaints and TMDs, based on clinical phenomena with corresponding symptoms, the close neurological relationship between otic and masticatory structures, and anatomical features of the tympanic cavity and jaw joint. Function of the tensor tympani muscle seems to be crucial to understanding TMD-related otologic symptoms. The tensor tympani inserts into the handle of the malleus and it modulates sound transduction in situations of excessive noise. This muscle is innervated by the trigeminal nerve, like the masticatory muscles. Voluntary eardrum movement by pathological tensor tympani contraction results in various otologic symptoms. Thus, co-contraction of the tensor tympani with the masticatory muscle could be a possible cause of TMD-related otologic symptoms. The tensor tympani is rather unrelated to the acoustic reflex, in which the stapedius is strongly involved. The tensor tympani seem to be controlled by proprioceptive information from the trigeminal sensory nucleus. The peripheral innervation pattern of the tensor tympani and masticatory muscles is also supposed to be interconnected. The middle ear structure, including the malleus, incus, and tensor tympani, of mammals had been adapted for acoustic function and lacks the masticatory role seen in non-mammalian jawed vertebrates. The tensor tympani in non-mammals is one of the masticatory muscles and plays a role in the modulation of sound transduction and mastication. After the functional differentiation of the mammalian middle ear, the nervous connection of the tensor tympani with other masticatory apparatus still remains. Through this oto-stomatognathic vestige, the tensor tympani seems to contract unnecessarily in some pathological conditions of the TMD in which the masticatory muscles contract excessively. We hypothesized that the phylogenic relationship between the tensor tympani and masticatory apparatus is a significant and logical reason for TMD-related otologic complaints.

Distribution of elastic fibers in the head and neck: a histological study using late-stage human fetuses / 대한해부학회지

There is little or no information about the distribution of elastic fibers in the human fetal head. We examined this issue in 15 late-stage fetuses (crown-rump length, 220-320 mm) using aldehyde-fuchsin and elastica-Masson staining, and we used the arterial wall elastic laminae and external ear cartilages as positive staining controls. The posterior pharyngeal wall, as well as the ligaments connecting the laryngeal cartilages, contained abundant elastic fibers. In contrast with the sphenomandibular ligament and the temporomandibular joint disk, in which elastic fibers were partly present, the discomalleolar ligament and the fascial structures around the pterygoid muscles did not have any elastic fibers. In addition, the posterior marginal fascia of the prestyloid space did contain such fibers. Notably, in the middle ear, elastic fibers accumulated along the tendons of the tensor tympani and stapedius muscles and in the joint capsules of the ear ossicle articulations. Elastic fibers were not seen in any other muscle tendons or vertebral facet capsules in the head and neck. Despite being composed of smooth muscle, the orbitalis muscle did not contain any elastic fibers. The elastic fibers in the sphenomandibular ligament seemed to correspond to an intermediate step of development between Meckel's cartilage and the final ligament. Overall, there seemed to be a mini-version of elastic fiber distribution compared to that in adults and a different specific developmental pattern of connective tissues. The latter morphology might be a result of an adaptation to hypoxic conditions during development.

Initial stage of fetal development of the pharyngotympanic tube cartilage with special reference to muscle attachments to the tube / 대한해부학회지

Fetal development of the cartilage of the pharyngotympanic tube (PTT) is characterized by its late start. We examined semiserial histological sections of 20 human fetuses at 14-18 weeks of gestation. As controls, we also observed sections of 5 large fetuses at around 30 weeks. At and around 14 weeks, the tubal cartilage first appeared in the posterior side of the pharyngeal opening of the PTT. The levator veli palatini muscle used a mucosal fold containing the initial cartilage for its downward path to the palate. Moreover, the cartilage is a limited hard attachment for the muscle. Therefore, the PTT and its cartilage seemed to play a critical role in early development of levator veli muscle. In contrast, the cartilage developed so that it extended laterally, along a fascia-like structure that connected with the tensor tympani muscle. This muscle appeared to exert mechanical stress on the initial cartilage. The internal carotid artery was exposed to a loose tissue facing the tubal cartilage. In large fetuses, this loose tissue was occupied by an inferior extension of the temporal bone to cover the artery. This later-developing anterior wall of the carotid canal provided the final bony origin of the levator veli palatini muscle. The tubal cartilage seemed to determine the anterior and inferior margins of the canal. Consequently, the tubal cartilage development seemed to be accelerated by a surrounding muscle, and conversely, the cartilage was likely to determine the other muscular and bony structures.

One Case of Objective Tinnitus due to Palatal and Middle Ear Myoclonus / 대한이비인후과학회지

Tinnitus is very frequent and internal noise that impaires the quality of life. Objective tinnitus, which may be caused by palatal and middle ear myoclonus, is an extremely rare disorder. Such tinnitus may present very rapid, irregular and involuntary vibratory sound. Because it is a very rare disorder and patients have difficulty expressing their symptoms of tinnitus, the examiner may miss the diagnosis unless a careful history taking and physical examination is done. We have experienced a patient with objective tinnitus caused by both palatal myoclonus and middle ear myoclonus, who responded poorly to medical therapy and injection of botulinum toxin. However, this patient is treated with pterygoid hamulus fracture and sectioning of the tensor tympani and stapedial tendons. We report a review of the literature and present a case of a 26-year old man who did not respond to medical treatment and had to be relieved of the symptoms with surgical intervention.

A Case of Objective Tinnitus due to Middle Ear Myoclonus Treated by Surgical Therapy / 대한이비인후과학회지

Objective tinnitus which may be caused by contraction of the tensor tympani and stapedial muscles is extremely rare. We present a case of middle ear myoclonus with voluntary palatal myoclonus in a musician. Otologic examination demonstrated rhythmic involuntary movement of the tympanic membrane after the exposure of loud sound or blowing of the musical instrument. Impedance audiometry confirmed the motion of tympanic membrane and those movements correlated with a tinnitus perceived by the patient. Palatal myoclonic motion, voluntarily evoked by the patient, was observed by oral examination and heard by Toynbee tube objectively. Medical treatment and directive counseling were effective for voluntary palatal myoclonus. However, the main symptom of tinnitus caused by middle ear myoclonus was not changed. The patient's tinnitus was cured by tympanotomy with sectioning of the tensor tympani and stapedial tendons.

Participación del nervio trigémino en el reflejo acústico humano / Role of the trigeminal nerve in the acoustic reflex in humans

Para investigar sobre la participación del nervio trigémino y del músculo tensor del tímpano en el reflejo acústico humano se planteó un estudio prospectivo en once pacientes portadores de neuralgia del trigémino y programados para microcompresión del Ganglio de Gasser con balón percutáneo. Todos los pacientes presentaron estudios audiológico normales, incluyendo umbrales tonales, BéKésy, logoaudiometría, potenciales evocados y timpanograma, así como integridad del nervio facial detectada por clínica y por electroneuronografía. Los once pacientes presentaban ausencia del reflejo acústico. Seis meses después de la compresión del Ganglio de Gasser, tres pacientes presentaron reflejo acústico normal y en el resto permaneció ausente. Los ocho pacientes que no presentaron reflejo cursaron con paresia de músculos masticadores. Nuestros resultados parecen indicar que para la integridad del reflejo acústico es necesario tanto el sistema facial como el trigeminal. El reflejo acústico puede ser una prueba útil en el estudio de la neuralgia de trigémino

Neuroanatomía: consideraciones neuroanatómicas / Neuroanatomy: neuroanatomical considerations

Clasicamente se describe el complejo del nervio trigémino conformado por dos componentes. Uno es motor voluntario, encargado de la inervación de los musculos de la masticación y del tensor del timpano. El otro es sensorial, relacionado con aferencias de dolor, temperaturas de la cara y membranas meningeas. El primero tiene origen real a nivel del núcleo motor del V par, localizado a nivel medio de la pretuberancia; mientras que el componente sensorial tiene origen real en el ganglio trigeminal localizado en la fosa media del cráneo. De este se derivan prolongaciones centrales orientadas hacia el núcleo sensitivo del V par, localizado a lo largo del tallo cerebral. Del mismo ganglio se desprenden prolongaciones periféricas, que se integran a las ramas oftálmicas, maxilar y mandibular extendidas hasta los receptores.