Toshio Imoto

The Role of the Endolymphatic Sac in Statoconial Formation and Degradation

In the present investigation we studied the morphology o the endolymphatic sac in guinea pig fetuses (age 20-, 30-, 45-, 60-days-old and newborns). Twenty-day and 30-days-old guinea pig fetuses often displayed small prismatic or hexagonally shaped granules, presumably representing miniature otoconia. The granules appeared freely in the lumen of the endolymphatic sac as well as incorporated in the cytoplasm of the freely floating cells or macrophages. The origin of these sac otoconia" as well as the possible role of the endolymphatic sac in statoconis turnover and metabolism is discussed.

Ciliary Activity in Patients with Nasal Allergies

SummaryNasal allergy is a disease ensuing from type-I allergic reactions in the nasal cavity. A correct understanding of this process requires further investigation of the non-allergic pathology present. In the allergic state, the function of the nasal cilia is considered to be involved in the invasion of allergens into the nasal mucosa, and may also be involved with the manifestation and progression of the disease produced. In the present study, we examined the ciliary activity of the nasal mucosa of 35 patients with nasal allergies by using the photo-electric method of Ohashi and Nakai to better understand the non-allergic pathologies present. The nasal cilia of four healthy volunteers served as controls. In addition, a multivalent analysis was made according to quantifying theory I in order to define the effects of various factors on ciliary activity in the nasal mucosa during the allergic state.The following results were found in our present study. Ciliary activity was observed in 32 of 35 patients with nasal allergy. The mean value of the ciliary activity in these patients was 498±195 beats/min, while that of the normal controls was 753±46 beats/min. The ciliary activity in the nasal mucosa in the allergic state declined as the morbid period was prolonged; this decline in ciliary activity was relatively great in cases of perennial allergies aggravated by season-specific allergens.

Blockage of reuniting duct in Meniere's disease

Conclusion: The bony saccular orifice to the bony groove of the ductus reuniens (reuniting duct) could not be visualized in the Menieres ear with significantly greater frequency compared with normal subjects, which suggests that the reuniting duct is affected by radio-opaque substances in CT findings. Objective: This study investigated a more specific, objective, and simpler strategy to diagnose Menieres disease by assessing the reuniting duct. Subjects and methods: We examined the ears of 12 patients with definitely diagnosed unilateral Menieres disease in stage 3 based on Menieres disease criteria proposed by the Committee on Hearing and Equilibrium of the American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS), and the ears of 12 normal control subjects using three-dimensional (3D) cone beam CT. Results: The bony groove of the reuniting duct between the saccule and cochlea was visualized in all control subjects. However, the bony saccular orifice to the bony groove could not be visualized in the lesional ear of Menieres patients with significantly greater frequency compared with those of the contralateral non-lesional ears and control ears (p < 0.01). This orifice was not patent in 66.7% (8 of 12 ears) on the lesional side but all contralateral non-lesional ears of the patients and normal control ears were patent.

The Clinical Picture of Meniere's Disease in the Light of Glycerin and Urea Tests

A mathematical-statistical analysis of the role of glycerin and urea tests in patients with Menieres disease is presented. Using the quantification method for multidimensional qualitative data, 13 variables were analysed. The younger the patient the stronger was the correlation between age and positive glycerin and urea tests. At ages over 50 years, no correlation to positive test results was found. The longer the duration of disease, the stronger was the correlation between this duration and a positive urea test. The glycerin test showed no correlation to the duration of the disease. Hearing losses of 40-69 dB were correlated both to a positive glycerin test and to a positive urea test. Greater hearing losses were correlated only to a positive glycerin test. Hearing losses of less than 39 dB were not correlated to positive results of either the glycerin or the urea test. Directional preponderance in the caloric test showed a correlation to a positive urea test. On the basis of these results a hypothesis has been formulated to explain how glycerin and urea might affect the internal ear.

Assessment of Meniere's disease from a radiological aspect – saccular otoconia as a cause of Meniere's disease?

Abstract Conclusion: Significant reduced visualization of the reuniting duct (ductus reuniens; RD), saccular duct (SD) and endolymphatic sinus (ES) in Menieres disease (MD) compared with normal control ears on three-dimensional (3D) CT imaging suggests the blockage of endolymphatic flow there with radiodense substances, which may be explained by dislodged otoconia from the saccule. These structures could be involved in the pathogenesis of MD. Objective: This study was designed to visualize and assess the RD, SD and ES in patients with MD using 3D CT. Methods: Sixty-two patients with a definite diagnose of unilateral MD, based on criteria proposed by the Committee on Hearing and Equilibrium of the American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS), were compared with contralateral ears and normal controls (26 ears) using 3D CT. The RD, SD and ES were scrutinized for patency on 3D CT images. Results: MD ears showed loss of continuity of the RD, SD and ES based on evaluation of 3D CT images, and differed significantly from normal healthy control ears (p < 0.01).

Visualization and assessment of saccular duct and endolymphatic sinus

Abstract Conclusion: The saccular duct and endolymphatic sinus run in the bony groove, before reaching the orifice of the vestibular aqueduct. We first clinically visualized this sulciform groove using three-dimensional (3D) cone beam CT images. This strategy can be useful to assess the condition of the saccular duct and endolymphatic sinus concerning the longitudinal flow system of endolymph. Objective: To assess the saccular duct and endolymphatic sinus in the endolymphatic system in order to advance clinical studies on inner ear dysfunction. Methods: The sulciform groove of the saccular duct and endolymphatic sinus of human subjects was analyzed by cone beam CT and compared with that of a cadaver. Results: We could obtain reconstructed 3D CT images of the sulciform groove of the saccular duct and endolymphatic sinus using several CT window levels.

Three-dimensional cone beam computed tomography imaging of the membranous labyrinth in patients with Meniere’s disease

Abstract Conclusion: Three-dimensional cone beam computed tomography (3DCT) images revealed characteristic malformations of the membranous labyrinth of the inner ear in Meniere’s disease (MD). The morphology of the membranous region between the vestibular cecum of the cochlea and the saccule of ears with MD was compared to that of healthy ears. The present study supports the hypothesis proposed earlier that reuniting duct blockade is a result of the dislodgement of saccular otoconia. Objective: To visualize the membranous labyrinth using 3DCT and to investigate the pathology of MD. Methods: A preparatory study was conducted to determine the optimal 3DCT window settings for the detection of water, muscle, calcium carbonate (CaCO3), and bone. Based on this preparatory study, the ears of 13 healthy volunteers and 25 MD patients definitely diagnosed according to the criteria issued by the Committee on Hearing and Equilibrium of the American Academy of Otolaryngology, Head and Neck Surgery (AAO-HNS), were visualized. Results: The differences in the membranous labyrinth between MD ears and healthy ears could be visualized using 3DCT. The images were classified into three types based on their morphological pattern. The ears of patients with MD were different from normal ears in terms of this classification.

Otoneurological Test Results Analyzed by Means of a Quantitative Statistical Method

This report is a presentation of an approach to the prediction of cerebellar-pontine (C-P) angle tumors and four peripheral vestibular diseases from a mathematical statistical point of view. The present study was performed in an attempt to quantify multidimensional, quantitative data. The data analyzed were from a total of 143 patients with C-P angle tumors, Menières disease, sudden deafness, vestibular neuronitis, and benign paroxysmal positional vertigo (BPPV). Tests were carried out mainly on otoneurological parameters. By means of discriminant analysis as employed in the quantification method, the patients were classified in the 4-dimensional space.

The Correlation between the Vestibulo-Ocular System and the Vestibulo-Spinal System in Ménière’s Disease Based on Categorical Principal Component Analysis

Correlations among different equilibrium function tests were investigated in 130 patients with Ménière disease. The tests consisted of 22 different items, and the possible results could be put into a total of 49 categories. Using a factor analytic method, results falling in the positive area of the 1st axis indicate normality of the vestibular system, and results in the negative area, indicate an abnormality of the vestibular system. On the 2nd axis, the negative direction indicates an abnormality of the vestibulo-spinal system, and the positive direction an abnormality of the vestibulo-ocular system. In this paper, relationships among sex, age, the Cornell medical index results, and the time between the vertigo attack and testing, as well as between the onset of the disease and testing, are shown on a two-dimensional plane.

Discrimination of peripheral and central vestibular disorders by means of a quantitative statistical method

This paper presents an approach to the prediction of peripheral and central vestibular disorders from a mathematical statistical point of view. An analysis was performed by the quantification method for multi-dimensional qualitative data. The data analysed were from 713 patients with a complaint of dizziness or vertigo who were subjected mainly to neurootological tests on 14 items. The categorical discriminant analysis of peripheral and central vestibular disorders revealed a discriminant success rate of 82%. We used the following five tests in discrimination: optokinetic test (OKN), caloric test, eye-tracking test (ETT), hearing test, and standing test. A system for the screening of patients with vertigo was assessed by use of a microcomputer and is in daily use in our department.