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S Awaya

Publications and source records attributed to S Awaya.

At least 19 recordsLinked to original sources
PubMed2001

[EDAS (encephalo-duro-arterio-synangiosis) for occlusive/stenotic cerebrovascular disease].

The efficacy of encephalo-duro-arterio-synangiosis (EDAS) using superficial temporal artery was evaluated for the treatment of the occlusive/stenotic cerebrovascular disease. Nine patients with the occlusive/stenotic cerebrovascular disease underwent EDAS in our hospital. The mean follow-up period was 6.6 months. Postoperative angiography showed no collateral formation via EDAS in any of the nine patients. We analyzed the following points: 1) operative procedure, 2) follow up period after surgery, 3) preoperative cerebral blood flow, and 4) age of the patients. Results showed that EDAS as a treatment of occlusive/stenotic cerebrovascular disease was not effective. This study failed to reinforce the suggestion that indirect extracranial/intracranial bypass surgery is effective as the treatment of occlusive/stenotic cerebrovascular disease.

Adult↗
PubMed1999

[Efficacy of three dimensional CT angiography (3D-CTA) for a first diagnosis of occlusive cerebrovascular disorders].

Patients with cerebrovascular disorders generally undergo computerized tomography (CT), even though magnetic resonance imaging (MRI) is available. We investigated the efficacy of three dimensional CT angiography (3D-CTA) for a first diagnosis of occlusive cerebrovascular disorders. Sixty-two patients, who were suspected of occlusive cerebrovascular disorder on the basis of neurological findings or initial plain CT findings, were reviewed. 3D-CTA was performed at the first medical examination. As a result, two patients were diagnosed with ICA (internal carotid artery) occlusion, nine with MCA (middle cerebral artery) occlusion, and one with BA (basilar artery) occlusion. All twelve patients underwent cerebral angiography immediately after those 3D-CTA in every case. Angiographical findings were the same as 3D-CTA. Interventional superselective thrombolytic therapy was performed in ten of the twelve patients, and recanalization resulted in four of them. 3D-CTA may also be able to determine whether the occlusive vessel is the chief cerebral artery or the perforating artery.

Adult↗
PubMed1999

[Cerebral blood flow (CBF) before and after cranioplasty performed during the chronic stage after decompressive craniectomy evaluated by xenon-enhanced computerized tomography (Xe-CT) CBF scanning].

Patients who undergo decompressive craniectomy for the purpose of prevention of cerebral herniation sometimes improve neurologically or increase activity of daily life after cranioplasty during the chronic stage. We studied the effect which cranioplasty at the chronic stage had on intracranial environment by means of xenon-enhanced computerized tomography (Xe-CT) CBF scanning. Eight patients underwent decompressive craniectomy at the acute stage and cranioplasty at the chronic stage was reviewed. Xe-CT CBF scanning was performed before and after cranioplasty. On the slice of the basal ganglia. CBF of the symptomatic hemisphere increased in five patients and CBF of the other hemisphere increased in three patients after cranioplasty. On the slice 20 mm above the basal ganglia, CBF of the symptomatic hemisphere increased in five patients and CBF of the other hemisphere increased in four patients after cranioplasty. Cranioplasty after decompressive craniectomy may increase CBF of not only the symptomatic hemisphere but also the other hemisphere.

Aged↗
PubMed1999

Binocular depth-from-motion in infantile and late-onset esotropia patients with poor stereopsis.

PURPOSE: There are at least two possible ways to detect motion-in-depth binocular without monocular cues: the binocular disparities at different times and a mechanism that detects interocular velocity differences. The perception of interocular velocity differences (Binocular depth-from-motion [BDFM]) depends on the relative velocity of the images on the retina of the left and right eyes, and this information can be experienced by normal and some strabismic patients. The purpose of this study was to determine the characteristics of esotropic patients who have BDFM but have poor stereopsis. METHODS: Forty-one infantile and 28 late-onset esotropia patients with poor stereopsis were studied. Dynamic stereopsis and BDFM were tested with computer-generated random dot stereograms and kinematograms. The correlations between BDFM and other binocular functional tests were determined. RESULTS: A total of 31 (44.9%) patients, 15 (36.5%) of the infantile and 16 (57.1%) of the late-onset esotropia group, passed the BDFM test. None of these patients passed the random dot stereo test under static or dynamic conditions. Fusion of the Worth four dot test at near 0.3 m was correlated with the presence of BDFM. Three of the 15 infantile and 10 of the 16 late-onset esotropic patients with positive BDFM showed gross stereopsis as measured by the Titmus Fly. The angle of strabismus was significantly smaller in the patients with positive BDFM for the infantile and the late-onset esotropia groups. CONCLUSIONS: BDFM was present in about half of the esotropic patients who do not have fine stereopsis. Ocular alignment within 10 to 15 prism diopters is an important factor in obtaining BDFM. Strabismus surgery still provides some binocular benefit for infantile esotropia patients who were bypassed for early surgery. Separate mechanisms may underlie static stereopsis and BDFM.

Adolescent↗
PubMed1999

[Moyamoya disease with intraventricular hemorrhage due to rupture of lateral posterior choroidal artery aneurysm: case report].

Intracranial aneurysms associated with moyamoya disease are often reviewed. Aneurysms not around the circle of Willis but on the collateral vessels are rare. A 71-year-old woman presented with sudden onset of severe headache and vomiting. CT scan showed an intraventricular hemorrhage from bilateral lateral ventricle to fourth ventricle. Cerebral angiography showed the occlusion of the terminal portion of the bilateral internal carotid artery with moyamoya vessels and three aneurysms at the distal portion of the left lateral posterior choroidal artery. Clinical symptoms improved day by day, but 17 days later, due to rebleeding of the aneurysms the patient fell into coma. The day after rebleeding, endovascular embolization was performed using liquid particle, and the left lateral posterior choroidal artery and the aneurysm were occluded. Brain infarction with massive brain edema of the left cerebral hemisphere resulted in the patient's death. The management of the aneurysms in the basal ganglia and on the collateral vessels associated with moyamoya disease is controversial. We suggest positive intervention during the acute stage for the peripheral artery aneurysms taking endovascular embolization into consideration to prevent rupture or rebleeding.

Aged↗
PubMed1997

Activation of non-selective cation conductance by carbachol in freshly isolated bovine ciliary muscle cells.

In smooth muscle cells freshly isolated from the bovine ciliary body, effects of carbachol (CCh) on the membrane potential and current were examined by the whole-cell clamp method. The resting membrane potential of the muscle cells used was -60 +/- 1 mV (n = 111). Extracellular application of CCh (2 microM) depolarized the cells to -15 +/- 5 mV (n = 50) with an apparent increase in membrane conductance. Under voltage-clamp conditions, CCh (2 microM) evoked an inward current which exhibited inward-going rectification and reversed the polarity at about 0 mV. Removal of Na+ from the external solution caused a reduction of the amplitude of the current and a shift of the reversal potential to the negative direction. CCh was able to elicit an inward current even under a condition where Ca2+ was the only cation producing an inwardly directed electrochemical gradient. The current was not affected by verapamil or by tetrodotoxin. The CCh-induced current was inhibited by antimuscarinic agents with the affinity sequence: atropine approximately 4-DAMP > > pirenzepine > AF-DX116, indicating that the response is mediated by a muscarinic cholinoceptor that belongs to the M3-subtype. Unlike the non-selective cation channel current in intestinal smooth muscles, which is activated by elevation of the intracellular Ca2+ concentration ([Ca2+]i), the current of the ciliary muscle was inactivated when the [Ca2+]i was increased. The conductance, which admits Ca2+, may serve as a pathway for Ca2+ entry required for contraction.

Animals↗
PubMed1997

Fluorescein angiography of peripheral retina and pars plana during vitrectomy for proliferative diabetic retinopathy.

PURPOSE: To evaluate the extreme peripheral retina and pars plana during vitrectomy in patients with proliferative diabetic retinopathy. METHODS: In a prospective study using a modified ophthalmic endoscopic system and an intraocular light source, we performed fluorescein angiography during pars plana vitrectomy in 12 eyes of 10 patients with proliferative diabetic retinopathy. Vitrectomy had been performed previously in two patients, and the subsequent surgery was necessary because of recurrent vitreous hemorrhage in one patient and silicone oil removal in the other. RESULTS: All 12 eyes of 10 patients demonstrated a wide avascular area in the peripheral retina anterior to the previous photocoagulation scar. At the ora serrata in two eyes, a fibrovascular ridge of peripheral retinal vessels with fluorescein leakage that resembled the demarcation line in retinopathy of prematurity was noted; one eye had developed neovascular glaucoma 4 weeks after vitrectomy with maximum augmentation of endolaser photocoagulation, and the other eye had neovascular glaucoma that had been treated with photocoagulation 1 year before vitrectomy. In the two eyes that had undergone previous pars plana vitrectomy, fluorescein leakage was apparent at the fibrous scar of the sclerotomy site. CONCLUSION: Intraoperative fluorescein angiography using an endoscope disclosed unusual findings in the extreme peripheral retina and pars plana of patients with proliferative diabetic retinopathy. Intraoperative fluorescein angiography may aid intraoperative evaluation and treatment of proliferative diabetic retinopathy.

Adult↗
PubMed1997

Identification of anterior uveal tumor border by transscleral transillumination and an ophthalmic endoscope.

PURPOSE: To report a method for identifying the borders of anterior uveal tumors in deeply pigmented eyes. METHOD: The borders of the anterior uveal tumors were marked by transscleral transillumination with a fiberoptic light and observed from the vitreous cavity using an ophthalmic endoscope. RESULTS: The ophthalmic endoscope disclosed a bright orange spot by transscleral transillumination of a normal uvea in deeply pigmented eyes. Two anterior uveal melanomas and one adenocarcinoma of the nonpigmented ciliary epithelium did not transmit light through the tumors. CONCLUSION: With an ophthalmic endoscope and transscleral transillumination, the borders of ciliary body tumors can be identified and clearly demarcated, even in deeply pigmented eyes.

Adenocarcinoma↗
PubMed1997

Treatment of fungal corneal ulcers with amphotericin B ointment.

PURPOSE: To report two patients with severe fungal corneal ulcers who were treated successfully with topical amphotericin B ointment. METHODS: Two eyes of two patients developed corneal ulcers and hypopyon after corneal foreign body removal. Aspergillus fumigatus and Fusarium solani were isolated in Patients 1 and 2, respectively. By antifungal susceptibility testing, amphotericin B was shown to have the lowest minimal inhibitory concentration. RESULT: Topical administration of amphotericin B ointment resulted in dramatic improvement in fungal corneal ulcers. CONCLUSIONS: Antifungal susceptibility tests may aid with selection of antifungal agents. Amphotericin B ointment is one of the promising therapies for keratomycosis caused by antimycotic-resistant fungi.

Administration, Topical↗
PubMed1997

[Aging of the blue mechanism studied by measuring the increment threshold on flashed background].

We studied aging of the blue cone mechanism by measuring increment thresholds for detection of a small blue flash of light (439 nm, 1 degree, 50 ms duration) on a second flashed light of identical color, (139 nm, 2 degrees, 500 ms duration) in 30 subjects. Simultaneously, a large yellow adapting field was presented. Subjects, consisting of 17 normal cases, 13 cases with refraction errors under 3 diopters, 11 myopes, and 2 hyperopes, with 1.0 or better corrected visual acuity, were divided into 4 groups by age. The control group consisted of 11 cases under 30 years, group I, 7 cases in their forties, group II, 6 cases in their fifties, and group III, 6 cases over 60 years. Best fitting exponential curves were calculated for this phase of the blue mechanism and averaged threshold curves for each group were evaluated. The averaged threshold curve in group I showed an upper shift, that is, an increase in the threshold alone. Curves in groups II and III demonstrated an upper right shift, with increased thresholds in both the blue flash and the yellow background. Together with decreased function of the blue cone mechanism, the shift of curves in the elderly groups is probably caused largely by yellowing of the crystalline lens.

Adult↗
PubMed1997

[Clinical applications of time-dependent perimetry (10) receptive field properties of glaucoma patients].

The receptive field center of double flash resolution (DFR) and of critical flicker fusion frequency (CFF) in a 3 degrees temporal visual field were examined in 11 normal subjects and 19 glaucoma and ocular hypertension patients. In normal subjects, the mean receptive field center of DFR was 2.17 log min of arc2 and that of CFF was 2.55 log min of arc2. In many glaucoma and ocular hypertension cases, the receptive field center of DFR (mean:2.48 log min of arc2) was significantly enlarged and came close to that of CFF (mean:2.53 log min of arc2)(p < 0.01). Although these findings were mostly seen in patients with some visual field changes, they were also encountered in 9 (70%) of the 13 cases with ocular hypertension without any visual field changes and are probably related to poor intraocular pressure control. We considered that the result was due to the dysfunction of the surrounding area of DFR that consists of interaction between sustained and transient functions of the visual pathway. This dysfunction could be closely related to the disorder of alpha-cells that occurs in the early stage of glaucoma.

Adult↗
PubMed1997

[Indocyanine green angiography in Stargardt's disease].

We performed indocyanine green angiography (ICG angiography) and fluorescein angiography in order to investigate the choroidal circulation in patients with Stargardt's flavimaculatus. Eight eyes of 4 patients in Groups 2 approximately 3 (Noble classification) were included in this study. In the area with "dark choroid" in fluorescein angiography, ICG angiography revealed large choroidal vessels in all eyes, but some fluorescent choroidal vessels were dark around the atrophic macula and in the peripapillary area, which indicated a greater storage of lipofuscin within the retinal pigment epithelium in those areas. In the atrophic macula area, irregular hypofluorescence was observed in ICG angiography, which might be caused by filling defect and/or block. Many flecks revealed hyperfluorescence in fluorescein angiography and hypofluorescence in ICG angiography, suggesting that focal circulatory disturbances in the choriocapillaries exist beneath the flecks.

Adolescent↗
PubMed1997

[Studies on ocular positions at close distance with a new system of measuring ocular positions].

The purpose of our study was to develop a new system of measuring ocular positions and to assess its clinical applicability. This system is derived from that of the Hess coordimeter and is used at a distance of 40 cm. Our system enables us to distinguish tropia from phoria by testing the ocular positions both with and without a fusional target which can be seen by both eyes. All devices are installed in one structure and it can be used in a lighted room. The system was checked in 10 normal subjects by plotting the data of the charts onto a graph and deriving a static eye position curve. There was no significant vertical deviation, and there was an exodeviation of 5.32 +/- 3.78 (mean +/- standard deviation) degrees without a fusional target, but no significant deviation occurred when the fusional target was lighted. In 37 of the 38 patients with ocular motor disturbance, the results with this system corresponded well with those obtained by the Hess coordimeter or prism cover test. One particular case with extraocular myositis involving more than two extraocular muscles showed an atypical complicated pattern. We believe that our system is simple and easy for clinical evaluation of ocular movement abnormality in ophthalmic diagnosis.

Adolescent↗
PubMed1997

[Immunohistochemical and immunogenetic analysis of ocular adnexal lymphoid proliferations].

We examined 20 cases (21 specimens) of ocular adnexal lymphoid proliferations, using the histological, immunohistochemical and molecular genetic methods. The latter two protocols were performed to detect the light chains restriction of immunoglobulin with peroxidase-antiperoxidase (PAP) methods, and the clonality of immunoglobulin heavy chain gene with the hemi-nested polymerase chain reaction (PCR) method, respectively. Although in 8 cases it could not be morphologically determined whether they were neoplastic or not, clonality was revealed in 1 case with immunohistochemistry and in 4 cases with PCR. Two cases showed discordant results between immunohistochemistry and PCR probably due to somatic mutation of the framework region of the immunoglobulin heavy chain gene. Therefore, we, concluded that examination with these methods contribute to a better understanding of the nature of the ocular adnexal lymphoid proliferations. Furthermore, the immunoglobulin gene PCR method is very useful in practical examination, as it can be used with formalin-fixed paraffin-embedded specimens.

Adult↗
PubMed1997

[Evaluation of the clinical usefulness of the New Aniseikonia Tests].

PURPOSE: We performed the following experiments to evaluate the clinical usefulness of the New Aniseikonia Tests (NAT). METHODS: 1. Aniseikonia was induced artificially by wearing a spectacle lens on the right eye and a contact lens on the left eye in myopic but otherwise normal subjects. The amount of aniseikonia detected was compared between the NAT and the Phase Difference Haploscope (PDH). Three different conditions were used with the PDH in order to study whether the fusional background affects the amount of the aniseikonia. 2. The size of aniseikonia was measured by the NAT in normal subjects. We presented the NAT in two ways in order to study if the method of presentation affects the result. One was the regular NAT which consists of 6 pairs of half-moons on each page, and the other one was one pair of half-moons on each page. RESULTS: The degree of aniseikonia measured was 1.4% smaller in the NAT than with the PDH. Backgrounds did not affect the amount of aniseikonia. Normal subjects showed essentially no aniseikonia regardless of the presentation technique of half-moons. CONCLUSIONS: NAT may underestimate the degree of aniseikonia, but the difference is too small to contraindicate clinical usage.

Adult↗
PubMed1997

[Binocular functions in amblyopia and strabismus].

Regarding the changing trends in the concept, definition, etiological classification, and criteria for diagnosis of amblyopia, we reviewed a total of 4,693 cases of amblyopia seen during the past 37 years. The amblyopia was divided into four types: strabismic, anisometropic, ametropic, and form vision deprivative. There was a definite trend for the incidence to decrease and for the diagnosis to be made during earlier age in recent years. Although favorable recovery of visual acuity is obtained after treatment of amblyopia and strabismus, there are difficulties in obtaining good binocular functions in early-onset amblyopia and strabismus. This feature was evaluated in regard to motion perception asymmetry (MPA) and binocular depth from motion (DFM). Many cases of early-onset amblyopia and strabismus showed no disparity stereopsis, or position stereopsis, in spite of the presence of DFM. The MPA appeared to be closely related to early-onset esotropia regardless of age, while it disappeared and motion perception became symmetric 4 to 5 months after birth in normal infants. The DFM seemed to play an important role in maintaining good motor alignment for several years after surgery. I developed a checkerboard pattern stimulator in 1978. This method proved to be useful in developing binocular functions and motor alignment by applying simultaneous bifoveolar stimulation and anti-suppression. Extensive exposure to the stimulation was essential for therapeutic success.

Adolescent↗
PubMed1996

Mitochondrial DNA mutations associated with the 11778 mutation in Leber's disease.

To clarify the characteristics of possible synergestic mitochondrial DNA (mtDNA) mutations associated with Leber's hereditary optic neuropathy (LHON), we analyzed the entire nucleotide sequences of mitochondrial genome of two Japanese patients from independent pedigrees harboring the 11778 mtDNA mutation, and compared their sequences with those of 47 disease and 6 normal controls. We have detected several unique mutations in the mtDNA in addition to the 11778 mutation. Two nucleotide substitutions, an A-to-G transition at position 856 in the 12S rRNA gene and an A-to-G transition at 14692 in the T psi C loop of the tRNA(Glu) gene, occurred at highly conserved sites among various species. These mutations in combination with the 11778 mutation might synergetically contribute to the pathogenesis of LHON.

Adolescent↗