Biomedical subjects

S Aso

Publications and source records attributed to S Aso.

At least 37 records · Page 2Linked to original sources

PubMed1994

Electrocochleography in the diagnosis of delayed endolymphatic hydrops.

It is known that delayed endolymphatic hydrops (DEH) occurs in patients with unilateral and/or bilateral profound hearing loss. In the ipsilateral and bilateral types of DEH, no audiological tests can be performed on the affected ear because of profound deafness, although these tests can be done in the contralateral type. Electrocochleography (ECochG) was recorded on better hearing ears in both types of DEH. The results showed an increased negative summating potential (SP) in 6 out of 10 contralateral DEH patients whereas it could be measured in only one of 10 ipsilateral DEH patients. The mean SP/AP ratio of the contralateral type was 0.42 which was significantly larger than that of the ipsilateral type. The results suggest that contralateral-type DEH has the same pathology in the cochlea as Meniere's disease, and that ECochG can distinguish between these two types of DEH.

Action Potentials↗

PubMed1994

[A case of tuberculous anal fistulae complicated by pulmonary tuberculous].

Tuberculous involvement of the anus is very rare at present as the result of BCG-Vaccination and improvement of public health. We report a juvenile case of tuberculous anal fistulae complicated to pulmonary tuberculosis. A 22-year-old male was admitted with symptoms of 13 month- history of intermittent anal pain, low grade fever and cough. Chest X-ray showed bilateral middle zone infiltrates with cavitation. Perianal inspection revealed a large ulcer with purulent exudate and a few fistulae. Sputum smears showed acid fast bacilli. A biopsied specimen of perianal fistulae showed granulomatous lesions with central necrosis, epitheloid cells and multi-nucleated giant cells. With three-drug antituberculous regimen, his symptoms resolved, radiographic infiltrates improved, and the perianal fistulae were cured. It was speculated that the tuberculous anal fistulae in this case were caused by the dissemination from the pulmonary focus via the hematogeneous and lymphogeneous routes, because any tuberculous lesion was not detected in the gastrointestinal tract and rectum.

Adult↗

PubMed1994

Perilymphatic fistula with no visible leak of fluid into the middle ear: a new method of intraoperative diagnosis using electrocochleography.

A new method for the intraoperative diagnosis of a perilymphatic fistula is presented. Two cases are reported in which the test clearly indicated the presence of a fistula even though no visible leak of fluid was noted by the surgeon. In each case, there was a clear history of vertigo and hearing loss. Preoperatively, the presence of a perilymphatic fistula was suggested using raised intrathoracic pressure test in electrocochleography (ECochG). During the surgery, there was no visible leak of fluid into the middle ear. Electrocochleography was undertaken intraoperatively by placing an electrode in the round window niche and suctioning the oval window area; in neither case was any ECochG change seen. Next the electrode was repositioned on the oval window and when the round window area was suctioned, obvious ECochG changes occurred. Action potential (AP) amplitude dramatically decreased in both cases and summating potential (SP) increased in one case.

Adult↗

PubMed1994

Electrocochleography in profoundly deaf children: comparison of promontory and round window techniques.

It is important to be able to accurately assess residual cochlear function in profoundly deaf children. Profound hearing loss in children requires special consideration, because the choice between a cochlear implant and a hearing aid depends on accurate estimation of the residual hearing. Previous reports confirm that promontory (needle) electrocochleography (ECochG) is useful for evaluation of residual hearing in severely deaf children, but there were some limitations in assessing the lower audiometric frequencies and for assessing profound hearing loss. It is argued that accurate placement of a round window electrode (RW ECochG) provides better recordings. Round window ECochG testing is performed under general anesthesia in young children and gives an opportunity for inspection of the middle ear using an endoscope. This report describes a special "golf club" electrode that can be placed under direct vision into the round window niche, minimizing the risks of damaging an abnormal round window while providing the optimum extracochlear recordings. Round window ECochG gives better responses, especially in lower audiometric frequencies, than conventional promontory ECochG. In the Sydney children's cochlear implant program, RW ECochG has become an essential preoperative test.

Audiometry, Evoked Response↗

PubMed1993

Clinical significance of the galvanic body sway test in cerebellopontine angle tumors.

Since 1984, we have been modifying a new method of recording fine body sway elicited by low current stimuli of less than 0.4 mA, and of quantitatively evaluating the responses by Fourier transform. In order to easily and early detect acoustic tumors, we have applied a test battery consisting ABR, caloric test and galvanic body sway test (GBST) to 31 cases with acoustic neurinoma, to 5 cases with other CPA-tumors, and to 24 cases suspected of having CPA tumors. Of 27 cases with acoustic neurinoma on whom the GBST was performed, 25 cases (92.6%) shows abnormal responses. On the other hand, the ABR was abnormal in all cases, except for one case in the early stage of an ear tumor. However, the ABR was positive in 12 cases out of 24 with suspected findings without tumor, but the GBST was positive in only 3 cases out of 17 tested. Moreover, 26 cases (83.9%) with acoustic tumors showed abnormal CP in their first caloric tests. Comparing these observations with the results of image diagnosis, we conclude that the GBST is as useful for detecting small acoustic neurinomas as the ABR and the carloric test. Therefore, we have routinely used a test battery consisting ABR, caloric test and GBST for evaluation of acoustic neurinomas. However, we could not differentiate between acoustic neurinoma and CPA-tumor by using the three-test battery.

Auditory Threshold↗

PubMed1993

The intravenously administered glycerol test.

Three different methods of performing the glycerol dehydration test were evaluated. Method one involved the oral administration of 50 g of 50% glycerol solution; method two was the intravenous administration of 500 ml of 10% glycerol in saline with 5% fructose; and method three involved the administration of 200 ml of the same solution. It was found that intravenous administration was safe and did not give any unpleasant side effects. Both intravenously administered methods appeared to give similar rates of positive diagnosis for Menière's disease.

Administration, Oral↗

PubMed1993

Furosemide VOR test for the detection of endolymphatic hydrops.

In order to detect endolymphatic hydrops, we applied three neuro-otologic examination methods, including the furosemide VOR test, the glycerol dehydration test, and electrocochleography in 61 patients with unilateral Menière's disease, 21 patients with delayed endolymphatic hydrops, and 10 patients with syphilitic labyrinthitis. The positive rate of the furosemide VOR test in patients with endolymphatic hydrops was more than 50%. Inconsistencies were observed between the results of the furosemide VOR test, the glycerol test and/or electrocochleography. Therefore, combined test battery of these tests is useful clinically for detecting endolymphatic hydrops in the vestibular and cochlear systems.

Edema↗

PubMed1993

Electrocochleography in syphilitic hearing loss.

Syphilitic labyrinthitis presents such symptoms as hearing loss, tinnitus, vertigo and/or dizziness, and is well known as one of the endolymphatic hydropic diseases. In order to elucidate the relationship between syphilitic hydrops and ECochG findings, we performed ECochG in patients with syphilis following our previously reported study of patients with Meniere's disease. Twenty-two patients who have been serologically and clinically diagnosed as having syphilitic labyrinthitis were examined with ECochG between December, 1982 and November, 1991. Of the 27 ears tested with ECochG, 2 showed no response due to severe hearing loss, and increased SP (SP/AP ratio > 0.37) was observed in 14 (56.0%) out of the remaining 25 ears. The SP/AP ratio of patients with syphilitic labyrinthitis was not significantly different from that of the patients with Meniere's disease or delayed endolymphatic hydrops, while it was significantly higher than that of the patients with sudden deafness and other types of sensorineural hearing loss. We conclude that the electrocochleographic features of endolymphatic syphilitic lesions resemble those in Meniere's disease.

Adult↗

PubMed1993

Changes in auditory evoked responses during intravenous lidocaine.

Auditory evoked responses in 21 cases with tinnitus were recorded before and after the administration of intravenous lidocaine. A dosage of 1 mg/kg body weight was diluted with 20% glucose (20 ml) and administered intravenously over a one-min period. The loudness of tinnitus was evaluated during electrocochleography (ECochG) or auditory brain-stem response (ABR) recordings using a score between 0 and 11. The stimulus sound was a tone burst in a frequency that corresponded to the pitch of tinnitus. AP latency on ECochG and the inter peak latency (IPL) of wave I-III and wave III-V on ABR were prolonged momentarily and tinnitus was reduced. These findings reveal that the sites of action for lidocaine are both the inner ear and the brain-stem.

Audiometry, Evoked Response↗

PubMed1993

Vestibular nerve disorder in patients suffering from sudden deafness with vertigo and/or vestibular dysfunction.

Vestibular nerve disorder (VND) in cases suffering from sudden deafness with vertigo was studied. Between 1987 and 1991, we observed 46 patients suffering from sudden deafness with or without vertigo, who had undergone the caloric test and galvanic body sway test (GBST). Twenty-seven patients had vertigo and canal paresis (CP) upon the caloric test, 6 vertigo without CP and 13 CP without vertigo. VND was detected in 12 of the 46 patients. All those with VND had vertigo and CP upon the caloric test, 12/27 (44%). The degree of hearing loss in those with VND was significantly (p < 0.05) more severe and their recovery of hearing loss was poorer than in patients without VND. These results indicate that VND is a common finding in cases of sudden deafness with vertigo especially in those with severe hearing loss.

Caloric Tests↗

PubMed1993

Result of decompression surgery in late-stage severe facial paralysis.

We investigated the usefulness of decompression surgery in the treatment of the facial nerve in 23 patients with severe complete facial paralysis regardless of etiology. All patients were followed up for at least one year after onset. Nine patients underwent decompression surgery within a month of onset (Group A), 10 underwent surgery at a later time (Group B), and 4 did not receive surgery (Group C). In Group A, 2 patients showed satisfactory recovery and 2 fair recovery. In Group B, 4 patients showed satisfactory outcome, and one patient who underwent surgery 131 days after onset showed fair outcome. No patient in Group C showed satisfactory or fair recovery. There were no significant differences among the three groups in the percentage showing sequelae after treatment. We conclude that decompression surgery is indicated even for patients with severe facial paralysis who have a history of palsy of 2 months' or more duration.

Facial Muscles↗

PubMed1993

Retro-labyrinthine disorder in cases with peripheral facial palsy.

In some previously reported cases, facial palsy, even in Bell's palsy, involved vestibular dysfunction. Vestibular dysfunction in facial palsy is considered to be due to a retro-labyrinthine disorder such as vestibular neuronitis or acoustic neuromas. For the past 9 years we have been using the galvanic body sway test (GBST) routinely for differential diagnosis of the vestibular system. This paper reports GBST detected, retro-labyrinthine disorders in facial palsy. From 1981 to 1989, equilibrium examinations were performed in 33 cases with Bell's palsy and in 12 cases with Hunt's syndrome within 2 weeks after the onset. GBST was tested in 10 out of the 17 cases showing canal paresis (CP) in the caloric test. Abnormal GBST responses were detected in 9 cases (90%), 4 (80%) with Bell's palsy and 5 (100%) with Hunt's syndrome. The incidence of abnormal GBST was very high not only in Hunt's syndrome but also in Bell's palsy. The results indicate that vestibular dysfunction combined with facial palsy is mainly due to a retro-labyrinthine disorder and suggest that what is called vestibular neuronitis might be caused by a pathogenesis similar to that of facial palsy.

Caloric Tests↗

PubMed1992

[Reproductive and developmental toxicity study of suplatast tosilate (IPD-1151T) (1)--Fertility study in rats by oral administration].

The effect of suplatast tosilate (IPD-1151T) on reproductive ability and fetal development of the rat was studied. IPD-1151T was administered orally at dose levels of 0 (control), 200, 600, and 1800 mg/kg/day for the premating, mating and early pregnant period. For parent animals, IPD-1151T caused no abnormalities in clinical signs, reproductive ability, or autopsy findings; the females at 1800 mg/kg/day showed a reduction in body weight gain from one week after the start of administration and a decrease in food consumption from the day of the start of administration to day 6 of pregnancy. For fetuses, IPD-1151T produced no abnormalities in external, visceral or skeletal examinations; embryofetal mortality was increased at 1800 mg/kg/day. The results suggest that the non-effective dose level of IPD-1151T is 1800 mg/kg/day for males and 600 mg/kg/day for females in general toxicity, 1800 mg/kg/day for both sexes in reproductive ability, and 600 mg/kg/day for fetuses under the conditions of this study.

Abnormalities, Drug-Induced↗

PubMed1992

[Reproductive and developmental toxicity study of suplatast tosilate (IPD-1151T) (4)--Perinatal and postnatal study in rats by oral administration].

In order to assess the effect of suplatast tosilate (IPD-1151T) on pregnancy of the rat, and the post natal development to maturity of the F1 generation, daily doses of 0 (control), 200, 600 and 1800 mg/kg/day were administered orally to female Wistar rats from day 17 of pregnancy to day 21 after delivery. All females were allowed to give birth and rear their young to weaning. F0 dams showed no treatment-related changes in general conditions including the state of delivery or nursing, gestation period, birth rate, or autopsy findings. The dams at 1800 mg/kg/day showed a tendency to reduction in body weight gain and a decrease in food consumption. F1 offspring showed no treatment-related changes in clinical signs on the birth day or during the nursing period, external examination on the birth day, general condition, physical or reflex development, open-field test, water multiple T-maze test, autopsy findings, organ weights, skeletal examination, reproductive ability, or histopathological examination on the reproductive organs of the animals of both sexes that failed to produce pregnancy. The offspring at 1800 mg/kg/day showed a reduction or its tendency in body weight gain. There were no treatment-related changes in any of reproductive parameters of F1 dams including external examination of F2 fetuses. The results suggest that the non-effective dose level of IPD-1151T is 600 and 1800 mg/kg/day for F0 dams in general toxicity and reproductive ability, respectively, and 600 mg/kg/day for F1 offspring in post natal development under the conditions of this study.

Abnormalities, Drug-Induced↗

PubMed1992

[Reproductive and developmental toxicity study of prednisolone farnesylate (PNF)--teratogenicity study in rabbits by subcutaneous administration].

The effect of Prednisolone farnesylate (PNF), a newly synthesized corticosteroid, on fetal development of the rabbit was studied. PNF was administered subcutaneously at dose levels of 0(control), 0.01, 0.05 and 0.25 mg/kg/day during the fetal organogenesis period. In the pregnant animals, PNF caused no abnormalities in clinical sign, body weight gain, food consumption, or autopsy findings at 0.01 and 0.05 mg/kg/day groups; the animals at 0.25 mg/kg/day group showed a reduction in body weight gain and food consumption. Two of 13 animals at 0.25 mg/kg/day group aborted. And hydrothorax, mucosal hemorrhage of the stomach, or fading of the liver were observed in some animals. In the fetuses, PNF was observed no abnormalities in external, visceral, or skeletal examination; slight increase of embryofetal mortality, or reduction of live fetal body weight and placental weight were observed at 0.25 mg/kg/day. The results suggest that the non-effective dose level of PNF is 0.05 mg/kg/day for pregnant females in general and reproductive toxicity, and for fetuses under the condition of this study.

Animals↗

PubMed1992

[Retinochoroidal adhesions of diode laser endophotocoagulation lesions. 1. Histopathology of rabbit eyes].

I experimented with a prototype diode laser in order to determine how effective it is for intraocular endophotocoagulation of the retina and how much energy is required to produce chorioretinal adhesions. Retinal endophotocoagulation was performed in all 8 eyes of 4 rabbits. I used power settings at 100-140, 200 and 300 mW and an exposure time of 0.2 seconds. The lesions produced with powers of 100-140 mW were faint whitish spots surrounded by grayish rings. One month after photocoagulation, there were chorioretinal adhesions histologically. The lesions produced with powers of 200-300 mW were characterized by intense whitish spots surrounded by grayish rings and histologically they were over-irradiated ones. One month after photocoagulation, rupture of the internal limiting membrane could be seen in one of the 300 mW lesions. It can be said that the retinal burn which appeared ophthalmoscopically as a faint whitish spot surrounded by a grayish ring may be the most useful to produce chorioretinal adhesion.

Animals↗

PubMed1992

[Histopathology of retinochoroidal adhesions of diode laser endophotocoagulation lesions in monkey eyes].

Retinochoroidal coagulation effect of 810 nm diode laser was studied using monkey eyes to determine the energy necessary to produce retinochoroidal adhesion safely. Power settings were at 100, 200 and 300 mW. The lesions produced with a power of 100 mW were faint grayish spots. One month after photocoagulation, there was degeneration from the outer granular layer to the superficial choroidal layer. However, chorioretinal adhesion was not obtained due to external limiting membrane formation. The lesions produced with a power of 200 mW were characterized by small whitish spots surrounded by grayish rings and retinochoroidal adhesions were produced by proliferated cells. However choroid were intensely coagulated, and there was a rupture of Bruch's membrane in one lesion. The lesions produced with a power of 300 mW were intense white spots surrounded by grayish rings. Histologically, severe cell loss of the retina was seen and three was no retinochoroidal adhesion. It can be said that it is difficult for 810 nm diode laser to obtain adequate retinochoroidal adhesion safely.

Animals↗

PubMed1991

Otoneurological findings in inner ear syphilis.

Eighty-one ears in 48 patients who had had ear syphilis for the past ten years were studied and otoneurological examinations reviewed. Twenty-five of 48 cases complained of vertigo, 13 of giddiness and/or unsteadiness, and 10 cases denied dizziness. Approximately one half of the patients had abnormal findings on primary equilibrium examinations, such as Mann's test and stepping test. Spontaneous nystagmus and positional nystagmus were frequently seen on electronystagmographic examinations. Many patients showed abnormal responses to the bithermal caloric test and pendular rotation (VOR) test. Moreover, 5 of 8 patients had positive furosemide VOR tests. On transtympanic electrocochleography, 13 of 22 ears demonstrated a dominant -SP response. Eleven of 26 ears had positive findings on an intravenously administered glycerol test. In conclusion, some cases of inner ear syphilis show the characteristic findings of endolymphatic hydrops.

Adult↗