Biomedical subjects

F Suga

Publications and source records attributed to F Suga.

11 recordsLinked to original sources

PubMed1976

Sensorineural deafness due to osteitis fibrosa.

A 91-year-old woman with deafness died from renal failure. Autopsy revealed osteitis fibrosa cystica generalisata, chronic myeloid leukemia, renal atrophy, and hyperplastic parathyroid glands. The temporal bones showed senile osteoporosis, osteitis fibrosa, and chronic myeloid leukemia. The inner ears showed extensive degeneration of cochlear sensorineural elements. The perilymph showed a general increased staining reaction with hematoxylin-eosin that was most evident in localized areas, where marrow spaces of osteitis fibrosa communicated directly with perilymph. It appears that the active diseased marrow exerted a toxic effect on the sensorineural elements of the cochlea by diffusion through the perilymph.

Aged↗

PubMed1976

Hereditary progressive sensorineural deafness.

Progressive sensorineural hearing losses found in seven members of three families are presented. Genetic transmission patterns in the study appeared to be autosomal dominant in two families and recessive in one family. The common audiological features of these cases include bilaterally symmetrical audiometric configuration and fairly good speech discrimination. The hearing losses of most of the cases appeared to begin at high frequencies progressing later to involve lower frequencies. The main histopathological changes in the temporal bones of one of the cases were degeneration of the organ of Corti and of the spiral ganglion in the lower cochlear coils and cystic degeneration of the stria vascularis in the upper coils.

Adult↗

PubMed1976

Labyrinthine anomalies in trisomy 13 mosaicism.

The temporal bone histopathology of a 2-month-old male with a bilateral cleft palate, cleft lip and polydactylia due to trisomy 13 mosaicism was studied. Anomalies in the ear involved a partial absence of the superior semicircular canal, an abnormally wide lateral semicircular canal, underdeveloped cochlear coils, an abnormally broad modiolus, an undeveloped organ of Corti and an underdeveloped basilar membrane in the basal turn of the cochlea, an unusually wide cochlear aqueduct, and deformed stapedial crura.

Adult↗

PubMed1976

Paget's disease and sensori-neural deafness: temporal bone histopathology of Paget's disease.

Four cases with Paget's disease of the temporal bone are presented to illustrate the pathogenesis of the associated deafness. One case illustrates the combination of severe deafness due to bilateral otosclerosis with probably asymptomatic bilateral Paget's disease. One case with advanced Paget's disease presents features to explain early stages of sensori-neural deafness before actual cellular invasion of the inner ear. One case of profound deafness due to Paget's disease presents a different stage of cellular invasion of the inner ear by the disease on each side. One case illustrates invasion of the internal auditory meatus by Paget's disease with infiltration of the acoustic division of the nerve and profound deafness.

Adult↗

PubMed1975

Control of the microcirculation of the inner ear.

In general, many similarities are seen between cerebral blood flow and cochlear blood flow in response to vasodilating drugs. Cochlear vessels appear to be weakly controlled by the adrenergic nervous system. Cholinergic agents dilate cochlear vessels, although the vasodilation in the cochlea does not necessarily cause an increase in cochlear blood flow because of the associated hypotension. The effect on the systemic circulation is too profound to make these agents clinically useful. Papaverine, dipyridamole, amyl nitrite, and the plasma kinins produce transient increases in cochlear blood flow. Ten per cent carbon dioxide and 90 per cent oxygen product progressive vasodilation as long as the mixture is inhaled. Hydralazine produces too profound an effect on systemic blood pressure. Histamine and betahistine increase cochlear blood flow but only in doses that produce bronchiospasm in the guinea pig. Nicotinic acid and nicotinyl tartrate have no effect on cochlear blood flow. If one considers safety and efficacy as well as patient tolerance, papaverine appears to be the drug of choice for increasing cochlear blood flow clinically. Histamine and betahistine appear to be acceptable alternatives. Betahistine is no longer available for clinical use because of the failure to demonstrate clinical efficacy of therapy.

Cochlea↗

PubMedDate not supplied

Labyrinthitis ossificans due to chronic otitis media.

Histopathology of two cases of unilateral labyrinthitis ossificans in the presence of bilateral chronic suppurative otitis media is presented. In both cases, ossification and fibrosis were limited to the scala tympani of the lower basal turn, apparently due to inflammation entering through the round window membrane. The round window was occluded by new bone and fibrous tissue presumably resulting in a conductive hearing loss in addition to the conductive loss due to middle ear lesions. Degeneration of the hair cells of the organ of Corti was limited to the lower basal turn where ossification and fibrosis occurred.

Adult↗

PubMedDate not supplied

Temporal bone histopathology of osteopetrosis.

The histopathology of the temporal bone of an eight and one-half-year-old girl with osteopetrosis (Albers-Schönberg disease) was studied to evaluate the pathogenesis of its frequent complications in hearing and facial nerve function. The patient was blind and had acute otitis media, but facial paralysis was not noted. Although the size of the temporal bone pyramid was markedly increased due to enormously thickened periosteal layer, changes in the endosteal and endochondral layers were less marked. Exostotic growth of periosteal bone was seen in the middle ear wall, and the tympanic cavity appeared to be narrowed. At the oval window region, the facial nerve was pushed down towards the stapes due to extreme overgrowth of periosteal bone of the epitympanum, and the superstructure of the stapes was imbedded deeply into the dislocated facial nerve and had strongly compressed it. Although the footplate was free from ankylosis, the crus of the stapes appeared to be immobilized because it was lodged in the facial nerve. Such changes appeared to be the pathogenesis of one form of facial nerve paralysis and conductive hearing loss associated with osteopetrosis.

Child, Preschool↗

PubMedDate not supplied

Histopathological observations of presbycusis.

Temporal bone histopathology of 17 aged patients who had spontaneous and gradually progressive bilateral sensorineural hearing losses associated with aging was studied. Six cases in the present material showed the gradually sloping audiometric curve; nine cases, abrupt high tone hearing loss; and two cases, the flat audiometric curve. The most prominent histopathological change in the inner ear was a decrease in the population of the spiral ganglion cells. However, diffuse senile atrophy was also often seen in the organ of Corti and the stria vascularis. A positive correlation between the degree of artheriosclerosis and the degree of sensorineural degeneration in the cochlea was not obtained in the present cases. Also, the correlation was not found to be consistent between the type of the audiometric curve and the localization of lesions in the sensory, the neural or the vascular elements in the cochlea. Our observations show that a certain type of audiometric curve does not necessarily indicate a lesion in a specific cochlear element.

Aged↗

PubMedDate not supplied

Inner ear degeneration in acoustic neurinoma.

The temporal bones of three cases of acoustic neurinoma are described to illustrate histopathological features of inner ear lesions due to chronic partial obstruction of blood circulation by the tumor in the internal auditory meatus. Degenerative changes in the inner ear due to acoustic neurinoma were evaluated and compared with changes in the opposite ear. The main pathological findings in the inner ear which were attributed to the tumor were degeneration of nerve fibers and of ganglion cells, degeneration of the stria vascularis, degeneration of the tectorial membrane, fibrosis and ossification of a semicircular canal. Fairly good preservation of sensory cells was observed in the presence of total degeneration of nerve fibers and ganglion cells and subtotal degeneration of the stria vascularis.

Aged↗

PubMedDate not supplied

Labyrinthitis ossificans.

Three cases with postinflammatory inner ear sequelae are presented to illustrate unusual histopathologic changes. Endolymphatic hydrops without changes in the perilymphatic system was present in one ear following "influenza" meningitis and labyrinthitis ossificans in the contralateral ear. The characteristic histopathological changes of the temporal bones with hematogenic bacterial infection were an extensive labyrinthine ossification associated with a generalized sclerotic change of the whole periotic bone. Bony fixation of the stapedial footplate occurred with the generalized inflammatory process of the otic capsule. Severe and diffuse labyrinthitis ossificans occurred in one case due to tympanogenic inflammation spreading through the round window membrane in the course of suppurative otitis media. A general immunosuppression leading to fatal termination was the apparent factor predisposing to the inner ear complication.

Adult↗

PubMedDate not supplied

Neural control of cochlear blood flow.

Effects of intraarterial and intravenous injections of autonomic nervous system agents on cochlear blood flow were studied in order to investigate the neural control of the inner ear vessels. Blood flow changes in the inner ear of the guinea pig were measured with an electrical impedance plethysmograph. Rather weak control of the vertebrobasilar and labyrinthine arteries by the sympathetic nervous system of the alpha-receptor type did appear to exist. Beta-receptors of the sympathetic nerve appeared to be non-existent in the cochlear vessels, and parasympathetic modulation was not evident.

Acetylcholine↗