Biomedical subjects

S Harino

Publications and source records attributed to S Harino.

34 records · Page 2Linked to original sources

PubMed1995

Indocyanine green videoangiographic findings in choroidal metastatic tumor.

BACKGROUND: Indocyanine green videoangiography (ICGV) has recently advanced and become widely available as a clinical tool. We tested the efficacy of ICGV in evaluating metastatic choroidal tumors. METHODS: ICGV using Topcon 50-IA was performed in five patients with clinically diagnosed choroidal metastatic tumors. The findings were compared with those of conventional fluorescein angiography (FAG). RESULTS: Compared with FAG, ICGV demonstrated more smooth and regular hypofluorescent lesions, precisely indicating the exact size of the tumor. In all cases, no tumor vessels were found. The choroidal vascular integrity around the tumors was observed. FAG, however, was more sensitive in detecting the tumor development than ICGV when the extent of the hypofluorescent lesion could be seen clearly in the early phase. FAG provided more information regarding retinal pigment epithelial dysfunction in the outer blood retinal barrier overlying the tumor. CONCLUSION: Since ICGV enables visualization of tumors through the retina, it is very useful, particularly in cases of associated secondary retinal detachment around the tumors. ICGV combined with FAG provides more precise assessment of the tumors themselves and their response to treatment than FAG alone.

Adenocarcinoma↗

PubMed1995

Rebreathing into a bag increases human retinal macular blood velocity.

AIMS: The effect of rebreathing into a bag (RB) on retinal macular blood velocity was evaluated in healthy volunteers. METHODS: Ten normal volunteers, whose ages ranged from 17 to 34 years, performed RB over 135 to 260 seconds (mean (SD) 193 (38) seconds) while retinal macular blood velocity was determined non-invasively using the blue field simulation technique. RESULTS: Leucocyte velocity significantly increased (p < 0.05) at 2 minutes and at the end of RB by 53% (42%) and 92% (65%), respectively (95% confidence interval of the mean (CIM)). All subjects observed an increase in the density of leucocytes. At the end of RB, mean systolic brachial arterial pressure and heart rate were significantly increased by 24% (11%) and 37% (15%) respectively (p < 0.01). At 2 minutes, end tidal oxygen concentration in the exhaled air was 47% (8%) (95% CIM) below and carbon dioxide was 41% (16%) above baseline (p < 0.001). The RB produces a large increase in macular leucocyte velocity, suggesting an increase in blood flow. CONCLUSION: Although RB has some systemic risk due to hypoxia and hypercapnia, RB for a short period of 1 or 2 minutes might be of help in the treatment of retinal arterial obstructive diseases in young patients without cardiovascular disorders if other treatments do not show any beneficial effects.

Adolescent↗

PubMed1995

[Optic disc and choroidal circulation detected by dye-filling rate in indocyanine green angiography].

Dye-filling rate of optic disc and choroid in normal human subjects was investigated using indocyanine green infra-red videoangiography and computerized image analysis. Only relative changes in the circulation of disc and choroid could be studied and the ratio (D/M) of dye-filling rate in normal subjects (age ranged 23-62) in disc (D) to choroid (M) was reliable. Intraocular pressure (IOP) was elevated to two levels with a pneumatic suction-cup. When D/M at normal IOP was 1, mean D/M was 1. 29 when mean IOP was 26.8 mmHg, and 1.48 when mean IOP was 38.4 mmHg. The results suggest that IOP elevation produced less change in the disc circulation than in the choroid. The ratio of dye-filling rate of the disc at 38.4 mmHg to normal IOP was significantly correlated (P < 0.05) with perfusion pressure at normal IOP, showing that the autoregulatory mechanisms in the disc blood flow may possibly reach the limit especially in subjects whose perfusion pressure is low.

Adult↗

PubMed1994

Survey of complications of indocyanine green angiography in Japan.

PURPOSE: We evaluated the safety of indocyanine green for use in fundus angiography. METHODS: We sent a questionnaire concerning complications of indocyanine green to 32 institutions in Japan, which were selected on the basis of the client list from the Topcon Company, which manufactures the indocyanine green fundus camera. RESULTS: Ophthalmologists at 15 institutions responded, reporting a total of 3,774 indocyanine green angiograms performed on 2,820 patients between June 1984 and September 1992. Before angiography, intradermal or intravenous indocyanine green testing, or both was performed at 13 of 15 institutions. For three patients, the decision was made not to proceed with angiography after positive preangiographic testing. The dosage of indocyanine green used for angiography varied from 25 to 75 mg, depending upon the institution. There were 13 cases of adverse reactions (0.34%), ten of which were mild reactions such as nausea, exanthema, urtication, itchiness, and urgency to defecate, and did not require treatment. Also recorded were one case of pain of the vein, which required treatment, and two cases of hypotension. The two hypotensive patients required treatment for shock. CONCLUSIONS: A comparison of frequency of adverse reactions to indocyanine green with the previously reported frequency of such reactions to fluorescein sodium indicated that indocyanine green is a safe as fluorescein for use in angiography.

Aged↗

PubMed1994

Chronic ocular ischemia associated with the Eisenmenger's syndrome.

We studied the ocular findings of two adult patients with the Eisenmenger's syndrome who had atrial septal defects that were diagnosed before the age of 10 years but not operated on and pulmonary hypertension. Both eyes of these patients showed microaneurysms, multiple small blot hemorrhages, or capillary dilation in the temporal peripheral fundus. Multiple microaneurysms and retinal collaterals were confirmed by fluorescein angiography. One of the patients developed bilateral rubeosis iridis with slow progression. These retinal lesions and the rubeosis iridis are probably related to chronic ocular ischemia caused by chronic systemic hypoxia.

Adult↗

PubMed1993

Transient hyperopia with lens swelling at initial therapy in diabetes.

The clinical courses of 10 eyes of five diabetic patients who exhibited bilateral transient hyperopia (maximum: 1:1-4.9 dioptres, spherical equivalent) after initiation of strict control of diabetes with or without insulin are reported. The hyperopia occurred within a few days after abrupt decrease in plasma glucose, progressed to maximum at days 7-14, and regressed gradually over 1 month thereafter. Transient cycloplegia had no effect on refractive error. During hyperopia, there were no significant changes in axial length or corneal curvature. However, thickened lens, decreased anterior chamber depth, and transient cataract were observed to significant degrees. It is suggested that the transient hyperopia, with lens swelling and opacity, was caused by decreased lens refractive index following water influx.

Adult↗

PubMed1993

[Potential laser hazards to bystanders during photocoagulation].

The authors measured reflected laser beams delivered by slit-lamp photocoagulator and binocular indirect ophthalmoscope laser delivery systems, to evaluate potential hazards to the eyes of bystanders. 514 nm laser beams were used; reflected laser beams were measured by a light power meter (Advantest: TQ8210). Reflected lasers were found to be hazardous at 1 meter from whitish tile when a 0.75 Watt laser beam was delivered by the binocular ophthalmoscope laser system, as in an operating room. At 1 meter from a wall in a photo-coagulating room for out-patients, the reflected laser beam was found to be well below hazardous levels. Reflections at 40 cm from a non-laser-coated Goldmann 3-mirror contact lens were 2.66 mW/cm2, which exceeds the exposure limits, when 0.3 W laser was delivered by the slit-lamp photocoagulator. This decreased 85-90% when the laser was reflected from a laser-coated lens. From the point of view of safety, it is recommended that laser surgeons replace non-laser-coated lenses with laser-coated ones.

Eye↗

PubMed1992

Laser Doppler flowmetry in the optic nerve.

Laser Doppler flowmetry (LDF) is a technique that measures relative average velocity, number and flux (number times velocity) of red blood cells in a tissue. In this paper, we demonstrate its application in the optic nerve head tissue, describe the laser delivery and light scattering detection schemes and investigate the effect of the distance between the sites of illumination and detection. We also provide evidence that the flow measured by LDF varies linearly with actual blood flow in the optic nerve and examine the question of the depth of the sampled volume. Experiments in anesthetized cats illustrate potential applications which make use of the high temporal resolution of LDF. These include the response of blood flow to changes in the composition of the breathing gases and changes induced by neuronal stimulation with multiple and single flashes.

Animals↗

PubMed1992

Intravenous nicardipine in cats increases optic nerve head but not retinal blood flow.

The effect of intravenously injected nicardipine on retinal and optic nerve head (ONH) blood flow was studied in 27 cats using laser Doppler velocimetry and flowmetry, respectively. A dose of 20 micrograms/kg of nicardipine had little effect on retinal blood flow. A dose of 100 micrograms/kg, however, produced a significant transient decrease in flow. By contrast, both doses produced a significant increase in ONH blood flow despite a significant decrease of the mean arterial blood pressure. Measurements of the partial pressure of oxygen (PO2) with an oxygen-sensitive microelectrode, whose tip was placed in the vitreous just in front of the optic disc, showed a significant increase in the PO2 that paralleled the increase in ONH blood flow. These results demonstrate, for the first time to the authors' knowledge, a pharmacologically induced increase in ONH blood flow and suggest that nicardipine could have a beneficial effect on ONH tissue.

Animals↗

PubMed1991

Flicker evoked increase in optic nerve head blood flow in anesthetized cats.

The effect of diffuse luminance flicker stimulation of a large area (approximately 30 degrees diameter) on red blood cell flux (F) in the optic nerve head was measured in the anesthetized cat. F increased markedly during sustained flicker. The F-response to the initiation and cessation of the stimulation was found to occur within a few seconds. Upon sustained stimulation, the increase in F reached a plateau within approximately 2 min. Its level depended upon the intensity, frequency and wavelength of the stimulation and the state of adaptation of the retina. This stimulus offers a new and powerful means of investigating blood flow regulation in the optic nerve head (ONH).

Adaptation, Ocular↗

PubMed1985

[Study on the transfer of cefroxadine to human tears].

A comparative study to determine the transfer of cefroxadine (CXD), an oral cephem antibiotic, to the human tears was undertaken using cephalexin (CEX) as the control drug. The mean tear levels of 250 mg each of CXD and CEX after oral administration in 6 volunteers were equally peaked at 0.26 micrograms/ml with CXD after 1 to 2 hours and with CEX after 2 hours. The changes of tear levels were also equal for both drugs. The ratios between the tear and the blood levels at 2 hours after oral administration were almost equal with 4.1% for CXD and 3.7% for CEX. From the above evidence it has been confirmed that the both drugs were equivalent with regard to the concentration profiles in human tears after oral medication.

Administration, Oral↗

PubMed1984

Skin test with varicella-zoster virus antigen for ophthalmic herpes zoster.

We assessed delayed dermal hypersensitivity to varicella-zoster virus by a varicella skin test in 12 patients (nine women and three men ranging in age from 27 to 85 years) with ophthalmic herpes zoster during the acute stage and in a group of 27 healthy controls (15 women and 12 men ranging in age from 18 to 58 years). Of the 27 healthy individuals, 25 had positive skin test reactions whereas only one of the 12 patients with ophthalmic herpes zoster had a positive skin test reaction within two weeks after the onset of the eruption, suggesting that cellular immunity to varicella-zoster virus antigens is impaired in the development of ophthalmic herpes zoster. Our study also showed that the varicella skin test is a convenient way to diagnose ophthalmic herpes zoster during the acute stage of the disease.

Adolescent↗

PubMed1980

The effects of protease inhibitors on histidine decarboxylase activities and assay of enzyme in various rat tissues.

Histidine decarboxylase (L-histidine carboxy-lyase, EC 4.1.1.22) of an extract of rat stomach was inactivated by a pancreatic extract. This inactivation was prevented by the protease inhibitors leupeptin, antipan, chymostatin, pepstatin, Trasylol and phenylmethanesulfonyl fluoride. Leupeptin, antipain, chymostatin and pepstatin together and phenylmethanesulfonyl fluoride alone prevented complete inactivation of the enzyme, while Trasylol had a weak protective effect. The inactivation and protection of histidine decarboxylase purified from whole fetal rats were similar to those of the stomach enzyme: both enzymes were strongly inactivated by trypsin and chymotrypsin, but not by elatase or carboxypeptidase Y. The histidine decarboxylase activities of various rat tissues were assayed in the presence of protease inhibitors: activity was highest in mast cells followed by the whole bodies of fetal rats and the stomach, while the activities were lower in decreasing order in the brain, spleen, lung and liver. Heart and kidney had no activity.

Animals↗

PubMedDate not supplied

Two-year follow-up study comparing primary vitrectomy with scleral buckling for macula-off rhegmatogenous retinal detachment.

PURPOSE: To compare the anatomic and visual outcomes achieved by scleral buckling and primary vitrectomy for the repair of macula-off rhegmatogenous retinal detachment. METHODS: The records were reviewed for a consecutive series of 167 patients (167 eyes) who were initially treated with scleral buckling or pars plana vitrectomy for primary macula-off retinal detachment. Patients were treated between January 1993 and December 1996. After adjustments for preoperative characteristics, data from 102 cases (55 scleral buckle cases and 47 primary vitrectomy cases) were used for the final comparison. There had been a minimum follow-up period of 24 months. RESULTS: No significant differences in single-procedure reattachment incidence (91%), final success incidence (100%) and incidence of postoperative proliferative vitreoretinopathy development (4%) were observed between the two treatment groups. Preoperative visual acuity, preoperative intraocular pressure, and duration of macular detachment were the three best predictors of postoperative visual recovery in both groups. Favorable overall visual recovery was obtained postoperatively, with no significant differences between the two groups throughout the follow-up period. However, in the eyes with poor preoperative visual acuity (<0.1), ocular hypotony (intraocular pressure <7 mm Hg), or prolonged macular detachment (more than 7 days), visual recovery in the primary vitrectomy group was significantly better (P <.05) than in the scleral buckle group from the first postoperative month. CONCLUSION: Both procedures achieved favorable anatomic and visual outcomes in the majority of patients with primary macula-off retinal detachment. Primary vitrectomy may be more effective than scleral buckling for achieving early visual rehabilitation in cases complicated by poor preoperative vision, ocular hypotony, and prolonged macular detachment.

Adult↗

PubMedDate not supplied

Clinicopathological report of retinitis pigmentosa with vitamin E deficiency caused by mutation of the alpha-tocopherol transfer protein gene.

PURPOSE: To discuss the clinicopathological findings in a patient with retinitis pigmentosa (RP) accompanied by a vitamin E deficiency caused by an H101Q mutation in the alpha-tocopherol transfer protein (alpha-TTP) gene. CASE: The clinical course of this patient was followed by conventional ophthalmological examinations over a 3-year period. After the patient died from pancreatic cancer, the eyes were obtained, and examined by light and electron microscopy. OBSERVATIONS: The patient complained of night blindness subsequent to adult-onset ataxia, although the ataxia was very mild. His visual acuity was 0.6 OU, and ophthalmoscopy revealed RP sine pigmento. Ring scotomas were detected, and the electroretinography, electro-oculography, and dark-adaptation were altered. Fluorescein angiography showed granular hyperfluorescence around the macula. No progression of the visual and neurological symptoms was observed during the 10 years he was taking oral vitamin E. Histopathological examination revealed the loss of the outer and inner segments of the photoreceptors in the area corresponding to the ring scotoma, as well as a disorganization and shortening of the outer segments in the peripheral retina. CONCLUSIONS: We conclude that the clinical and pathological findings in the eyes of this patient having RP with vitamin E deficiency caused by an H101Q mutation are similar to those of common autosomal recessive RP. However, special attention is required in making a diagnosis of RP with vitamin E deficiency because RP with vitamin E deficiency is medically treatable. The mild Friedreich-type ataxia accompanying the RP may be helpful in identifying this disease.

Carrier Proteins↗

PubMedDate not supplied

Effect of hyperbaric oxygen on ophthalmic artery blood velocity in patients with diabetic neuropathy.

To assess the relationship between blood flow and the complications of diabetes mellitus, we investigated the changes in the velocity of blood flow in the ophthalmic artery before and after hyperbaric oxygen therapy (HBO), one of the treatments for diabetic neuropathy. Color Doppler imaging was used before and after HBO. Seven diabetic neuropathy patients, 3 diabetics without neuropathy, and 7 normal, control subjects were enrolled. The patients were subjected to breathing 100% oxygen at 2.0 atmosphere absolute (ATA) for 1 hour. Hyperbaric oxygen therapy resulted in an average decrease in blood velocity by 15.0 +/- 9.0% (mean +/- SD) in normal subjects and 10.7 +/- 8.6% in diabetics without neuropathy. Blood velocity returned to the baseline level 4 hours after discontinuation of HBO. In contrast, blood velocity increased by 20.6 +/- 9.5% in diabetic patients with neuropathy irregardless of the severity of the diabetic retinopathy. The resistance index of the ophthalmic artery was not changed during HBO in the group with diabetic neuropathy, indicating that other mechanisms may be implicated, leading to the compensatory changes of blood flow. These results suggest that the increase in the blood velocity in the ophthalmic artery after HBO in diabetic neuropathy patients could be attributed to an imbalance in autonomic nervous function.

Autonomic Nervous System↗