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Seiyo Harino

Publications and source records attributed to Seiyo Harino.

14 recordsLinked to original sources
PubMed2007

Plasma endothelin-1 levels depress optic nerve head circulation detected during the glucose tolerance test.

PURPOSE: To determine the relationship between the changes in optic nerve head (ONH) circulation and the level of plasma endothelin-1 (ET-1) during the glucose tolerance test (GTT). METHODS: Twenty-six healthy volunteers with normal GTT and 15 patients with mild hyperglycemia and abnormal GTT were studied. The ONH circulation [square blur rate (SBR) value], blood pressure, intraocular pressure (IOP), blood glucose, blood insulin and plasma ET-1 were determined before and every hour up to 3 h after an oral intake of 75 g of glucose. RESULTS: The SBR increased in the normal glucose tolerance group at all times during the GTT, but it decreased significantly in the abnormal glucose tolerance group (P < 0.05). Before the GTT, the plasma ET-1 level was not significantly different in the two groups; however, the level increased 1 h after the oral GTT in the abnormal glucose tolerance group (P < 0.05). No significant changes were observed in mean blood pressure or IOP. CONCLUSIONS: ONH circulation increased after glucose intake in the normal glucose tolerance group and remained high even after the blood glucose level had returned to its baseline. The decrease in ONH circulation in the abnormal glucose tolerance group was attributed partly to the increased ET-1.

Adult↗
PubMed2006

Relationship between macular microcirculation and progression of diabetic macular edema.

PURPOSE: To investigate the relationship between blood flow velocity in perifoveal capillaries and retinal thickness at the central fovea in diabetic patients with clinically significant macular edema to elucidate the pathogenesis of diabetic macular edema. DESIGN: Comparative, cross-sectional, prospective study. PARTICIPANTS: Participants included diabetic patients with clinically significant macular edema (n = 22), matched diabetic patients without clinically significant macular edema (n = 22), and healthy volunteers (n = 16). METHODS: Perifoveal capillary blood flow velocity was measured with fluorescein angiography using a scanning laser ophthalmoscope and was analyzed by the tracing method. The severity of perifoveal capillary abnormalities among diabetic patients without clinically significant macular edema was classified by the size and outline of the foveal avascular zone and extent of foveal capillary loss at the baseline by the use of fluorescein angiograms. Retinal thickness at the central fovea was measured by optical coherence tomography. MAIN OUTCOME MEASURES: Relationship between perifoveal capillary blood flow velocity and retinal thickness at the central fovea. RESULTS: Perifoveal capillary blood flow velocity was significantly slower in the patients with clinically significant macular edema (0.94+/-0.09 mm/second) compared with the patients without clinically significant macular edema (1.22+/-0.20 mm/second) and the healthy volunteers (1.49+/-0.11 mm/second; P<0.0001). Capillary blood flow velocity negatively correlated with retinal thickness at the central fovea (r = -0.4018, P<0.0001). Capillary blood flow velocity varied among diabetic patients without clinically significant macular edema, and there were significant negative correlations between capillary blood flow velocity and the size of the foveal avascular zone (r = -0.52, P = 0.01), the outline of the foveal avascular zone (r = -0.44, P = 0.04), and the extent of foveal capillary loss (r = -0.51, P = 0.01). CONCLUSIONS: The reduction of perifoveal capillary blood flow velocity may occur before the increase of retinal thickness at the central fovea in the diabetic patients. It is possible that long-term reduction of blood flow velocity increases retinal thickness of the macula and may play an important role in the development and the progression of diabetic macular edema.

Aged↗
PubMed2004

Reduction of retinal blood flow in high myopia.

PURPOSE: To investigate changes in retinal vessel diameter and blood velocity in high myopia using laser Doppler velocimetry. METHODS: Thirty-nine subjects (39 eyes) were enrolled in the study. The subjects were divided into three groups according to their refractive status; 15 eyes (15 patients) with emmetropia (within +/-3.0 diopters), 14 eyes (14 patients) with mild myopia (between -3.0 and -8.0 diopters), and 10 eyes (10 patients) with high myopia (>-8.0 diopters). Patient age was matched between groups. Blood velocity and vessel diameter of the upper or lower temporal retinal artery were measured using laser Doppler velocimetry with an eye-tracking system, and measurements were compared between groups. RESULTS: The average retinal blood flow and vessel diameter in highly myopic eyes were significantly decreased compared with emmetropic eyes or mild myopic eyes (Mann-Whitney U test, p<0.05). Also, there was significant difference regarding retinal blood flow and vessel diameter between eyes with mild myopia and the other groups. In addition, there was no significant difference in blood velocity between the three groups. CONCLUSIONS: Retinal blood flow was decreased in high myopia, mainly due to the narrowing of the retinal vessel diameter. Impaired retinal blood flow might have a role in the development of chorioretinal atrophy in high myopia.

Adult↗
PubMed2004

Vitrectomy and internal limiting membrane peeling for myopic foveoschisis.

PURPOSE: Myopic foveoschisis is common in high myopia. We report results of a pilot study of vitrectomy for patients with myopic foveoschisis. DESIGN: Interventional case series. METHODS: In an institutional setting five patients with high myopia (six eyes), and who had progressive visual impairment presumably due to myopic foveoschisis were studied. No eyes had a macular hole preoperatively based on optical coherence tomography (OCT). We performed vitrectomy including vitreous cortex removal, internal limiting membrane (ILM) peeling, and gas tamponade. Patients were followed for at least 6 months. Best-corrected visual acuity (BCVA), OCT. Scanning laser ophthalmoscope (SLO) microperimetry was examined in three eyes. RESULTS: The foveal detachment resolved completely in five eyes and partially in one eye. No serious complications developed including macular hole formation or retinal detachment; BCVA improved more than two lines in all eyes (100%) 6 months postoperatively (P <.01); SLO microperimetry showed smaller scotoma compared with preoperatively and stabilized fixation. CONCLUSIONS: Vitrectomy with vitreous cortex removal, ILM peeling, and gas tamponade could be useful to treat myopic foveoschisis in highly myopic eyes. Because the natural course of the disease is not well-understood, further study should establish indications for this surgery.

Basement Membrane↗
PubMed2004

[Clinical course and macular retinal circulation of macular retinal epithelium atrophy].

PURPOSE: To investigate the clinical course of age-related maculopathy that mainly consists of retinal pigment epithelial abnormality and macular retinal circulation between the affected eye and the fellow normal eye. PATIENTS AND METHODS: Seventeen patients (19 eyes) with age-related maculopathy were followed for more than two years. We investigated visual acuity, ocular fundus appearance, and fundus angiographic findings. We studied macular retinal leukocyte blood flow measured by blue field simulation in 19 patients whose fellow eye was normal. RESULTS: Age-related maculopathy in 18 eyes (95%) showed no change and choroidal neovasculation did not occur during the observation period. Male patients (88%) were more affected than female patients (12%). The visual acuity in the 18 eyes (95%) did not change. Only one case lost two lines of visual acuity, and the area of macular degeneration increased. Macular retinal leukocyte circulation expressed by the leukocyte density, and leukocyte density multiplied by the leukocyte velocity in the affected eyes deteriorated compared to the normal fellow eyes. CONCLUSION: We demonstrated that progression of age-related maculopathy is very slow, and macular retinal leukocyte circulation measured by blue field simulation may be disturbed in age-related maculopathy.

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PubMed2003

Modified technique to create retinal detachment during macular translocation surgery.

PURPOSE: To report a modified technique for creating total retinal detachment during macular translocation surgery with a 360-degree retinotomy. DESIGN: Interventional case series. METHODS: After vitrectomy, BSS Plus (Alcon, Fort Worth, TX, USA) was injected into the subretinal space with a 39-gauge needle to create a small retinal detachment. The tip of a 20-gauge silicone-tipped needle was then placed in the hole created by the needle, and BSS Plus was injected subretinally at a high flow rate. RESULTS: In 10 eyes (10 patients), we created one iatrogenic retinal hole in seven eyes and two holes in three eyes. The time needed to create total retinal detachment was decreased. CONCLUSIONS: Our technique seems to make creation of a total retinal detachment easier compared with the previous standard procedure and may reduce postoperative complications following macular translocation surgery with a 360-degree retinotomy.

Bicarbonates↗
PubMed2002

Change in retinal arterial blood flow in the contralateral eye of retinal vein occlusion during glucose tolerance test.

PURPOSE: To investigate the changes in retinal blood flow (RBF) during a 75-g oral glucose tolerance test in the contralateral eye of patients with retinal branch vein occlusion (BRVO). METHODS: Seventeen patients with BRVO were included. None had a known history of diabetes mellitus. The blood velocity and vessel diameter of the upper temporal retinal artery in the contralateral eye were measured using laser Doppler velocimetry with an eye-tracking system before and 1, 2, and 3 h after oral intake of 75 g glucose. Blood sugar, systemic blood pressure, and intraocular pressure were monitored. Eleven healthy volunteers were examined similarly as control. RESULTS: Nine patients (53%) with BRVO had an abnormal pattern on the glucose tolerance test. RBF significantly increased at 1, 2, and 3 h in eight patients with normal glucose tolerance. The changes in RBF primarily resulted from changes in vessel diameter; the blood velocity did not change significantly. The nine patients with impaired glucose tolerance or diabetes mellitus had a RBF pattern that was significantly lower at 2 and 3 h than those with normal oral glucose tolerance. In the control group, all 11 volunteers showed the same increases in RBF at 2 and 3 h as the BRVO patients with a normal glucose pattern. CONCLUSION: A relatively high number of patients with BRVO had an abnormal pattern on glucose tolerance testing. Glucose intake increased RBF in BRVO patients without diabetes and in healthy volunteers. The RBF response may differ between subjects with diabetes and those without diabetes.

Aged↗
PubMed2002

[Long-term enlargement of laser photocoagulation scars after treatment of choroidal neovascularization].

PURPOSE: To investigate long-term enlargement of laser photocoagulation scars after treatment of choroidal new vessels (CNV) in age-related macular degeneration or myopic neovascular maculopathy. OBJECTS AND METHOD: Twenty-four eyes of 24 patients aged between 45 and 77 years were treated with laser photocoagulation for juxtafoveal or extrafoveal choroidal neovascularization in Yodogawa Christian Hospital. There was no recurrence in any of the eyes and the mean follow-up period was 31.0 +/- 13.7 (mean +/- standard deviation) months (13-60 months). The laser photocoagulation scar was measured with an image analyzer immediately and once a year after the treatment. We investigated the relationship between scar expansion rate and visual axis measured by A-mode ultrasonography. RESULTS: Expansion of the coagulation scars (atrophic creep) was observed in 19 eyes (79.2%). The coagulation scar expanded with the length of the period after treatment in most of the patients. The expansion rate was significantly correlated with the length of the eye at two years after treatment in all 24 eyes and even in 21 of the eyes without high myopia (p < 0.05). A decrease in visual acuity was observed in only one eye (4.2%). Remarkable pigmentation around the scar was found in three eyes of five that did not have atrophic creep. CONCLUSION: Although atrophic creep occurs in approximately 80% of eyes after successful laser treatment, visual acuity deterioration is rarely encountered. The rate of expansion is significantly correlated with the axial length among the eyes both with and without high myopia. Heavy pigmentation around scars may be one sign which indicates a low expansion rate of atrophic creep.

Aged↗
PubMedDate not supplied

Tracing method in the assessment of retinal capillary blood flow velocity by fluorescein angiography with scanning laser ophthalmoscope.

PURPOSE: To evaluate the feasibility of a new method (the tracing method) for measuring perifoveal capillary blood flow velocity (BFV). METHODS: The BFV in the perifoveal capillaries was measured in 12 eyes of healthy subjects and 12 eyes of patients with clinically significant macular edema (CSME) by fluorescein angiography using a scanning laser ophthalmoscope by either the tracing method or the conventional method. A randomized crossover design was employed to assign the subjects to each method. RESULTS: The number of capillaries recognized by the tracing method in healthy subjects and in patients with CSME was significantly higher than that recognized with the conventional method (P = 0.0134 and P = 0.0108, respectively). The number of fluorescent dots detected by the tracing method in healthy subjects and in patients with CSME was also significantly higher than that detected with the conventional method (P = 0.0002 and P = 0.0137, respectively). Accurate detection of the movement of fluorescent dots and analysis of BFV were possible with the tracing method. The BFV varied within each perifoveal capillary, and the mean BFV also varied according to capillary location in the macula. CONCLUSION: The new tracing method is useful for analyzing the retinal capillary BFV in healthy subjects and in patients with CSME.

Aged↗
PubMedDate not supplied

A novel relation of fatty acid with age-related macular degeneration.

To evaluate the relation between fatty acids and age-related macular degeneration (ARMD), the fatty acid fractions within the red blood cell (RBC) membrane and plasma of 11 ARMD patients and 10 healthy individuals (controls) were determined and compared. RBC arachidonic acid (AA) and docosahexaenoic acid (DHA) exhibited significantly higher values in the ARMD patients than in the controls. RBC levels of palmitic, palmitoleic, oleic and linoleic acids, however, showed significantly higher values in the controls than in the ARMD patients. No significant variations were observed between the two groups in terms of plasma levels of AA, DHA, palmitic, palmitoleic, oleic and linoleic acids. Our findings indicate that polyunsaturated fatty acids, vulnerable to free radicals and reactive oxygen species, and easily peroxidized, may be related to ARMD induction.

Aged↗