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1.
Steady-state pattern electroretinogram (PERG) in response to sinusoidal gratings (1.7 c/deg spatial frequency; 9 × 9 deg field size) temporally modulated (sinusoidally) at 8 Hz were recorded in 40 insulin-dependent diabetics and 28 age-matched normal subjects. Visual acuity was 20/20 in all 40 patients; 31 (62 eyes) showed no sign of retinopathy and nine (18 eyes) showed a few microaneurysms on fluorescein angiography. Insulin-dependent diabetics showed a significant reduction in the PERG mean amplitude as compared with age-matched control subjects (one-way analysis of variance: p < 0.0001). Significant differences were observed between normals and diabetics without retinopathy (Scheffé test: p < 0.0001), normals and diabetics with early retinopathy (Scheffé test: p < 0.0001), no retinopathy and early retinopathy patients (Scheffé test: p < 0.05). In diabetics without retinopathy multi-factorial analysis of variance revealed a significant effect of age of onset of the disease (p < 0.01) and an interaction effect between age of onset and duration (p < 0.001) on PERG amplitude. These results suggest a possible use of the steady-state PERG to detect early macular dysfunction in insulin-dependent diabetics.  相似文献   

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Vitreous fluorophotometry (VFP) using the Fluorotron Master was performed in 25 insulin-dependent diabetic patients with either minimal or no retinopathy and 22 controls. At 30 minutes, baseline corrected vitreous fluorescence values 3 mm from the retina were significantly greater in diabetic patients with minimal retinopathy than in either controls or patients with no retinopathy but were similar in patients with no retinopathy and controls. At 1 hour, vitreous fluorescence values and fluorescein permeability indexes were similar in all three groups. The absence of increased posterior vitreous fluorescein leakage in the diabetic patients with no retinopathy suggests that the alteration in permeability of the blood retinal barrier, as assessed by current VFP measures, does not precede the development of clinical diabetic retinopathy. However, the significantly increased 30-minute 3-mm fluorescence values suggest that posterior fluorescein leakage is increased in minimal background diabetic retinopathy.  相似文献   

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In order to appreciate quantitatively the effect of strict metabolic control obtained with continuous insulin infusion, we have carried out a clinical, angiographical and vitreofluorophotometrical follow-up during a mean period of 36 months, on 21 eyes of 11 patients treated with intraperitoneal insulin pump for brittle diabetes. Patients had no (5 patients) or minimal retinopathy (less than 10 microanevrysms, no exsudate or ischemic areas) (6 patients). At the same time, vitreous fluorophotometry was performed on one eye of 15 volunteer patients without any ocular or general pathology. Vitreous fluorophotometry measurements were made with the Fluorotron Master; after substraction of background autofluorescence, and spread function, results are expressed by the level of posterior vitreous penetration by fluorescein. Good metabolic control was achieved during the study (mean +/- S.D. glycemia = 1.47 g/l +/- 0.21, mean +/- S.D. HbA1 = 7.99% +/- 0.84). Final visual acuities were identical to initial ones, there was no angiographical evolution of the retinopathy, and final vitreous fluorophotometry data (OD = 4.19 10(-6)/mn +/- 0.44 S.E.M., OS = 3.28 10(-6)/mn +/- 0.51 S.E.M.) did not statistically differ from the initial data (OD = 3.88 10(-6)/mn +/- 0.49 S.E.M., OS = 4.08 10(-6)/mn +/- 0.64 S.E.M.). On the contrary, volunteers' measurements (2.15 10(-6)/mn +/- 0.26 S.E.M.) were significantly lower than initial (p less than 0.01) and final (p less than 0.05) diabetics' measurements. These results confirm the early breakdown of the blood-retinal barrier during diabetic disease, and would support the notion of a favorable effect of strict metabolic control on early stages of diabetic retinopathy.  相似文献   

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Ten age-matched normals, diabetics with retinopathy, and diabetics without observable retinopathy were evaluated by vitreous fluorophotometry (VFL) using a 0.15 mm and a 0.45 fiberoptic probe in a photomultiplier system as well as a commercially available photodiode instrument to determine whether differences in intraocular sodium fluorescein levels could be detected among the three groups. Each subject was injected in the antecubital vein with 7 mg/kg of sodium fluorescein (25% solution) and measurements were taken 1 hr postinjection at 4.5 mm and 7.5 mm from the retina. The influence of choroidal fluorescein and ocular pigmentation are reduced at these locations. We found that a breakdown in the blood-ocular barrier may not be present early in the course of diabetes. Furthermore, no significant difference was found between normals and diabetics without retinopathy. Although the mean value for vitreous fluorescein was significantly higher in diabetics with retinopathy compared to normals, several of the diabetics with retinopathy had values in the normal range. These results differ from those previously reported in the literature. However, our studies took into consideration several factors not considered by other investigators, such as ocular pigmentation, choroidal fluorescence, slit width, and vitreous changes, that may have significant effects on the fluorophotometry values.  相似文献   

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The authors investigated by transmission electron microscopy bioptic specimens obtained during pars plana vitrectomy. In the findings phagocytozing cells predominate. Due to cell damage accurate typing is difficult. The authors discuss the causes and extent of cellular damage. From morphological findings the conclusion can be drawn that in the histological picture macrophages, hyalocytes and damaged collagen fibrils predominate.  相似文献   

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The cause of retinopathy in diabetes mellitus is unknown. Among factors suggested to be involved in the development of retinopathy is altered platelet function. In the present study, platelet aggregation was measured in vitro after stimulation with adenosine diphosphate (ADP) and collagen in patients with and without proliferative retinopathy. The results show that patients with proliferative retinopathy have an increased platelet aggregation in vitro after stimulation with collagen and ADP. However, the increased platelet aggregation was also found to be correlated to the duration of diabetes. Thus, the present study does not support the opinion that abnormal platelet function can be regarded as a primary cause of diabetic retinopathy. Increased platelet aggregation seems to be coupled to the duration of diabetes and to still unknown factors developing with prolonged duration of the disease.  相似文献   

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In a retrospective study we have examined all diabetics (66 operated eyes) and an equal number of non-diabetic matched controls who underwent extracapsular cataract extracation (ECCE) with intraocular lens (IOL) implantation over a two-year period ending in December 1987. Of the diabetic patients' 76% eyes improved by at least two lines of Snellen acuity postoperatively. Of these patients 68% eyes and of the control eyes 83% achieved an acuity of 6/12 or better. In the diabetics the visual outcome depended on the state of the retinopathy and in particular the maculopathy. The diabetic group had a greater incidence of postoperative inflammation, but the major complications were related to continuing neovascularisation. Early postoperative laser photocoagulation may help to prevent these proliferative complications, and, provided a large, adequate capsulotomy is performed for capsular thickening, the presence of an IOL does not interfere with this photocoagulation. We also advise early postoperative assessment, and treatment if necessary, of any maculopathy. Diabetic retinopathy should no longer be regarded as a contraindication to intraocular lens insertion.  相似文献   

11.
Nyctometry was used to assess macular recovery function in 234 diabetic patients; their retinopathy ranged from no retinopathy (99) to early background retinopathy (135). None had visual symptoms or macular oedema. Abnormal (reduced) nyctometry findings were significantly and directly related to the deterioration of diabetic retinopathy. There was no significant association between reduced or normal nyctometry findings and glycaemia at the time of the examination. The value of nyctometry in screening and follow-up is discussed.  相似文献   

12.
Importance of the vitreous in young diabetics with macular edema   总被引:3,自引:0,他引:3  
F P Nasrallah  F Van de Velde  A E Jalkh  C L Trempe  J W McMeel  C L Schepens 《Ophthalmology》1989,96(10):1511-6; discussion 1516-7
The authors assessed retrospectively the clinical records of 80 patients (137 eyes) with diabetic retinopathy who were 50 years of age or younger and who had undergone a vitreous examination. The group comprised 53 patients (91 eyes) with macular edema and 27 patients (46 eyes) without macular edema. Vitreous studies using the El Bayadi-Kajiura lens determined whether the posterior vitreous was attached to the retina in the macula. Forty (42.1%) of 91 eyes in the edema group and none (0%) of the 46 eyes in the nonedema group had a detached posterior vitreous. This difference was statistically significant, indicating that young diabetic patients with macular edema have a significantly higher rate of posterior vitreous detachment than those without macular edema.  相似文献   

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PURPOSE: Can oscillatory potentials be a useful method for detection of retinal dysfunction in insulin-dependent diabetics without retinopathy? MATERIAL AND METHODS: In this study scotopic oscillatory potentials (OPs) were obtained in 35 subjects (70 eyes) with insulin-dependent diabetes without retinopathy (mean disease duration--5 years) and in 15 healthy subjects (30 eyes). This examination was performed according to the recommendations of the International Society of Clinical Electrophysiology of Vision (ISCEV). The oscillatory potentials were extracted from the maximal combined response by high-pass filtering. We analysed amplitude and peak-latencies of the first three electroretinographic oscillatory potentials O1, O2, O3, index of wavelets [sum of amplitudes (O1 + O2 + O3)] and compared with the results of the control group. RESULTS: In group of patients with insulin-dependent diabetes without retinopathy, we received statistically significant reduction of amplitude O1 (p < 0.003) and index of wavelets (p < 0.04). Reduced amplitude O1 was obtained in 10%, index of wavelets in 31.4% of analysed eyes. We didn't observe statistically significant changes in amplitudes O2, O3 and latencies O1, O2, O3. CONCLUSIONS: Our results suggest that retinal dysfunction is present in insulin-dependent diabetics without retinopathy 5 years after onset of the disease. The sum of amplitudes (O1 + O2 + O3) was the most sensitive parameter of retinal abnormalities. It seems reasonable to have more frequent ophthalmological examination of the diabetics with abnormal oscillatory potentials.  相似文献   

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OBJECTIVE: To study the aqueous humor dynamics in subjects with human immunodeficiency virus (HIV) with and without cytomegalovirus (CMV) retinitis. DESIGN: Prospective cross-sectional study. PARTICIPANTS: Fourteen HIV-positive subjects (27 eyes, 19 with CMV retinitis and 8 without CMV retinitis), and a control group of 9 HIV-negative subjects (17 eyes). TESTING: Fluorophotometry. MAIN OUTCOME MEASURES: Aqueous flow rates as measured by fluorophotometry and intraocular pressure (IOP). RESULTS: Analysis of variance of the mean corrected aqueous flow rate revealed that both HIV-positive groups had significantly lower aqueous flow rates than did the control group (P < 0.03). No difference in mean aqueous flow rates was found between the HIV-positive eyes with or without CMV retinitis. Comparison of mean IOP revealed that HIV-positive eyes with CMV retinitis had significantly lower IOP than did the HIV-positive eyes without CMV retinitis (P = 0.03) and HIV-negative subjects (P = 0.002). There was no correlation between aqueous flow rate and IOP in HIV-positive subjects (P > 0.5). CONCLUSION: The lack of correlation between the aqueous flow rate and IOP suggests that there may be some disassociation between these parameters in HIV-positive patients. Further studies are needed to better understand the mechanism of aqueous formation and in the management of disorders affecting IOP in this population.  相似文献   

18.
Adrenomedullin (AM) is a multifunctional peptide with various physiological actions, including vasodilatation, a defense mechanism against microorganisms, the regulation of growth and the regulation of insulin and glucose. In this study, we measured the vitreous AM levels in patients with diabetes mellitus to determine its potential involvement in the pathogenesis of diabetic retinopathy (DR). We used an immunoradiometric assay to measure the vitreous AM concentrations in a total of 28 eyes: 13 with DR and 15 with macular holes (15 men and 13 women, 62.9 +/- 10.4 years old). The AM levels in the vitreous fluid of patients with DR (22.9 +/- 7.9 fmol/ml) were found to be significantly higher than the corresponding AM levels in patients with macular holes (4.7 +/- 1.1 fmol/ml) (p < 0.05). These results indicate that the increase in the vitreous AM is related to DR.  相似文献   

19.
The focal electroretinogram, which measures the functional integrity of the distal retina of the macula, was recorded with a hand-held stimulator-ophthalmoscope in 26 eyes from patients with non-insulin-dependent diabetes mellitus with normal fundus photography, and in 52 control eyes of similar age range. Implicit time and amplitude of the responses were studied as a function of the age, glycemic control through glycosylated hemoglobin measurement and duration of diabetes. Implicit time and amplitude were significantly delayed (F=5.05, p=0.028) and reduced (F=11.26, p=0.013) in diabetic patients without diabetic retinopathy compared to control subjects. Moreover, there was a significant relationship between the implicit time (r=0.57, p=0.002) and amplitude (r=−0.65, p=0.0004) with the duration of diabetes but not with hemoglobin Alc. These results strongly suggest an early macular dysfunction in noninsulin-dependent diabetes mellitus before the appearance of diabetic retinopathy.  相似文献   

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