Yoshinobu Hirono

Observation of the external aperture of the vestibular aqueduct using three-dimensional surface reconstruction imaging

Observation of the external aperture of the vestibular aqueduct was hitherto possible only in cadavers or dry temporal bones; however, by applying three‐dimensional surface reconstruction imaging, it is now possible to observe solid‐looking images of this structure in living humans. When the width of the external aperture of the vestibular aqueduct was measured in 58 people, it was found to be significantly narrower in the affected ears of patients with Menieres disease than in normal ears.

Occurrence of Sequelae in Bell's Palsy

The occurrence of sequelae in 330 patients with Bells palsy followed up for more than 6 months was investigated. At least one of five kinds of sequelae (synkinesis, crocodile tears syndrome, spasm, contracture, tinnitus and/or hearing loss during facial movement) was observed in 30 of the 330 cases (9.1%). Sequelae occurred at 23.9-39.0 weeks (mean) after onset of palsy and at scores of 30-34 points (mean; full score 40 points). The incidence of sequelae was correlated to the degree of facial nerve dysfunction.

Olfactory neuroblastoma: Presentation of a case and review of the japanese literature†

Olfactory neuroblastoma is an uncommon malignant tumor arising from the nasal cavity. During the past 18 years from 1964 to 1982, only 24 cases have been in Japanese literature, including this case. The average age of these patients is 42.3 years, ranging from 4 to 75 years old. The sex ratio of male to female is 10:14, female being prevalent moderately. The peak distribution is from 30 to 40 years old. The majority of the patients died of distant metastasis within 2 years of diagnosis. Therefore, the overall prognosis in Japan is very poor, as compared with about a 50% 5 year survival rate in the western countries. This is probably because this tumor is difficult to diagnose correctly, and the chance to start treatment early is apt to be missed here, though some tumors behaved very aggressively from the beginning, metastasizing early.

Three-dimensional computer graphics of the eustachian tube

Images of the eustachian tube from various directions were obtained using computer graphics. Serial cross sections of a human temporal bone specimen including the eustachian tube were digitized for reconstruction. Wire-frame models of the structures such as the eustachian tube lumen, the tubal cartilage, the tensor veli palatini muscle, and the levator veli palatini muscle were drawn. Through observation of the eustachian tube from various directions with the tubal muscles attached or detached, the physiology of the eustachian tube system could be understood more clearly.

Persistent Stapedial Artery Associated with Otosclerosis (With 1 color plate)

A 43-year-old female had bilateral otosclerosis with a persistent stapedial artery in the left ear which measured approximately 0.4 mm in diameter, lying on the floor of the tympanic cavity, running b

The Developing Electrolytes Concentrations of Inner Ear Fluids in Guinea Pigs

Cochlear endolymph, scala tympani perilymph, and scala vestibuli perilymph were collected from fetal, neonatal, and mature guinea pigs. The concentrations of Na and K in these fluids were then assessed using a microflame photometer. The electrolyte composition in the endolymph was already characterized by a high concentration of K and a low concentration of Na by the 49th day of gestation.

Middle-Ear Paraganglioma Masquerading as Traumatic Facial Nerve Palsy With 1 color plate

We report the case of a 52-year-old female with middle-ear paraganglioma masquerading as a traumatic facial palsy, and describe the diagnostic steps and surgical treatment by the tympanomastoid approach.

Effects of Glycerol on the Inner Ear Fluid Electrolytes of Guinea Pigs —Oral and Intravenous Administration—

Under sodium pentobarbital anesthesia (25-35 mg/kg), serum, CSF and inner ear fluids from scala tympani perilymph, scala vestibuli perilymph, and scala media endolymph were collected from normal guinea pigs after the oral administration of glycerol (50%, 12 ml/kg) or the intravenous injection of glycerol (1.0 ml/kg). The sodium and potassium concentrations were assessed by microflame photometry. The electrolyte dynamics of the inner ear fluids were compared after these two routes of administration. Serum: There was no significant change in Na or K levels after either route of administration. CSF: The Na concentration increased rapidly after both intravenous and oral administrations of glycerol and remained high until the end of the experiment. The K concentration did not change significantly after intravenous injection. Scala tympani perilymph: The Na concentration increased transiently, after intravenous glycerol, while after oral administration it increased slowly and steadily. The K concentration increased only after oral administration. Scala vestibuli perilymph: The Na level increased slowly and steadily only after oral administration of glycerol, and the K level increased slightly after intravenous injection. Scala media endolymph: No changes in the K level occurred after either route of administration. After oral administration the Na level increased. These experiments show that dehydration persists longer after oral than after intravenous administration of glycerol. In the diagnosis of Menieres disease, oral administration of glycerol is more effective than intravenous injection.

Free Sigmoid Colon Autograft Reconstruction of the Hypopharynx and Cervical Esophagus; A Case Report.

In a patient with cancer of the hypopharynx and cervical esophagus reconstruction was performed with a free Sigmoid colon autograft. The feeding vessels of this autograft were anastomosed by microvascular surgery. A reconstructed esophagus made from a free Sigmoid colon has less peristalsis than one from a free jejunum. Therefore, our patient did not have swallowing difficulties after the beginning of oral feeding 2 weeks after operation. From this aspect, Sigmoid colon autografts seem to be better than jejunum autografts in the reconstruction Qf the hypopharynx and cervical esophagus.

Influence of an inclined floor on the stepping test.

The stepping test was performed on an inclined floor (3°) in 8 normal subjects and 32 patients with problems of equilibrium. In the normal subjects, the inclined floor changed the relationship between the information of pression on the right and left portion of the body through the cutaneoplantar senses, and the goniometric information from the tibioperoneotarsal joint through the Ruffini sensory endings, stabilized their equilibrium a little. In the subjects with labyrinthine disorders, the inclined floor did not change the results of the stepping test. On the contrary, in patients with disorders of the central nervous system (i. e. head injury, etc.) or central or peripheral disorders of the proprioceptive system (i. e. whiplash injury), the inclined floor decreased the angle of rotation of the stepping test. Therefore, the stepping test on an inclined floor is useful as a routingc test in the differential diagnosis of patients with problems of equilibrium.