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K Schulte

Publications and source records attributed to K Schulte.

At least 37 records · Page 2Linked to original sources
PubMed1994

[Follow-up of arteriosclerosis-induced anterior ischemic optic neuropathy].

In 22 patients with acute arteriosclerotic anterior ischemic optic neuropathy (AION), examinations were conducted before the start of therapy and between 1 and 3 years later. In the acute stage of the disease the patients were treated with hemodilution for 10 days. The visual acuity improved from 0.2 to 0.4 (median). Compared with the visual acuity before therapy, at the follow-up 1-3 years later visual acuity had improved by 3 lines or more in 11 patients, remained stationary in 9 patients (+/- 1 line), and worsened in 2 patients by 3 lines or more. The visual fields (Goldmann) improved in 8 patients, did not change in 10 patients and worsened in 4 patients. After 1-3 years, 14 patients (64%) showed a sectorial pallor and 8 patients (36%) a diffuse pallor of the optic disc. Videofluorescein angiography revealed hypofluorescent discs in all patients. No difference in arm-retina time (ART) was found between the acute phase (13.0 +/- 3.3 s) and the examination 1-3 years later (13.1 +/- 2.2 s). ART was within normal limits in all patients. The arteriovenous passage time (AVP) dropped significantly, from 2.36 (+/- 0.81) s in the acute phase to 1.91 (+/- 0.56) s 1-3 years later. However, the AVP still did not fall to normal levels (1.45 +/- 0.40 s). Slowed retinal hemodynamics (AVP) with normal ART at the same time suggests a disturbance in microcirculation still present 1-3 years after the acute phase of AION. The rheological parameters (hematocrit, plasma viscosity, erythrocyte aggregation index) did not show any change between examinations.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1994

Retinal hemodynamics after pars plana vitrectomy with silicone oil tamponade.

Pars plana vitrectomy with silicone-oil tamponade is frequently performed in cases of complicated retinal detachment. Because of the lower specific gravity and the lower surface tension of silicone oil in comparison with the aqueous phase of the vitreous, an influence on the blood flow in the retinal vessels would be expected. However, not only the silicone oil but also the operative trauma and a buckling procedure may have an influence on the retinal blood flow. To examine this question we measured the arteriovenous passage time in the silicone-oil-filled eye and in the contralateral eye in 14 cases using a laser scan ophthalmoscope at 3-5 days after surgery. The arteriovenous passage time is a parameter for the retinal microicirculation. In all cases we found a prolonged arteriovenous passage time in the silicone-oil-filled eye in comparison with the contralateral eye (mean value +/- SD, 2.5 +/- 0.8 vs 1.25 +/- 0.25 s; P < 0.01). The prolongation of arteriovenous passage times observed in silicone-oil-filled eyes indicates that the microcirculation is worsened at least during the early postoperative period.

Adult↗
PubMed1993

The induction of early response genes in rat smooth muscle cells by PDGF-AA is not sufficient to stimulate DNA-synthesis.

The effect of the three platelet-derived growth factor (PDGF) isoforms AA, AB and BB on the induction of the early growth response genes c-fos, egr-1 and c-myc mRNA in vascular smooth muscle cells from rat was compared with their respective mitogenic potency. The three PDGF isoforms strongly stimulated the induction to a similar extent. In contrast, PDGF-AB and -BB provoked a marked DNA synthesis whereas PDGF-AA exerted only a poor mitogenic effect in smooth muscle cells. PDGF-AA-stimulated receptor autophosphorylation was not detectable in comparison with the strong effect elicited by PDGF-AB or -BB and correlated with its low mitogenicity but not with the almost equal induction of the early response genes. It is discussed that no or only very low receptor phosphorylation is required to link receptor activation to the induction of c-fos, egr-1 or c-myc. Furthermore the induction of the investigated gene does not seem to be sufficient for an optimal mitogenic response.

Animals↗
PubMed1993

Retinal hemodynamics using scanning laser ophthalmoscopy and hemorheology in chronic open-angle glaucoma.

PURPOSE: Recent studies suggest that elevated intraocular pressure is not the only causative factor for the development of visual field loss and optic nerve damage in glaucomatous eyes. The authors determine whether retinal hemodynamics or blood fluidity are alternated in eyes of patients with open-angle glaucoma compared with those of age- and sex-matched healthy subjects. METHOD: High-quality video fluorescein angiograms were obtained from single eyes of 51 patients with chronic open-angle glaucoma. From these angiograms, the arm-retina time, mean dye velocity, and arteriovenous passage time were quantified. The data from patients were compared with those of an age- and sex-matched group of healthy subjects. RESULTS: In patients with chronic open-angle glaucoma, an 11% reduction of the mean dye velocity (P < 0.05) and a 41% prolongation of the arteriovenous passage time (P < 0.01) was observed relative to the values obtained among the control subjects. Among hematocrit values, plasma viscosity, and erythrocyte aggregation, only plasma viscosity showed a significant increase (4%; P < 0.01) in patients with chronic open-angle glaucoma. CONCLUSION: These results indicate that a pronounced circulatory deficit exists within the retinal vasculature of glaucomatous eyes, which may coexist with, but cannot be fully attributed to, an increase in plasma viscosity.

Adult↗
PubMed1993

[Hemodilution therapy in patients with acute anterior ischemic optic neuropathy].

A prospective study was performed in 22 patients with an anterior ischaemic optic neuropathy (AION). All patients underwent iso- (Hct > or = 42%) or hypervolemic (Hct < 42%) haemodilution for 10 days with daily infusion of 250 ml hydroxyethyl starch (MW 200,000/0.5, 10% HAES-sterile) in combination with pentoxifylline (p.o.: 1200 mg/day; i.v.: 300 mg/day; Trental). Only patients with recent AION (less than 2 weeks' duration of symptoms) were considered for the prospective trial. Clinical, haemodynamic (arterio-venous passage time) and rheological (haematocrit, plasma viscosity, erythrocyte aggregation) data of all patients were recorded before therapy and after 10 days. An improvement of central vision by 2 or more lines was seen in 7 patients after 10 days. Initially the arterio-venous passage time was significantly prolonged in patients (2.42 +/- 0.7 s) with AION compared with healthy volunteers (1.45 +/- 0.4 s). After the 10-day trial arterio-venous passage time was significantly shorter than baseline values. In addition, the initially elevated plasma viscosity (1.33 +/- 0.1 mPa) was significantly lowered by haemodilution therapy.

Aged↗
PubMed1993

[Retinal hemodynamics in patients with arterial hypertension].

Arterial hypertension is a risk factor for the development of retinal, cerebral and renal microangiopathy. Therefore, a prospective study was started to investigate the progression of retinal microangiopathy in hypertensive patients. Initially, 254 patients were examined in a cross-sectional study. Following an ophthalmological examination, retinal hemodynamics were quantified by means of video-fluorescence angiography. Moreover, blood fluidity (hematocrit, plasma viscosity and erythrocyte aggregation) was analyzed. The severity of the retinal changes was defined according to the Neubauer classification. One hundred (40%) patients showed retinal changes corresponding to stage I; 133 (52%) were classified as stage II. Hypertensive retinopathy (stage III and IV) was encountered in 20 (8%) patients. Arm-retina time was significant prolonged among the hypertensive patients compared with a control group. Arteriovenous passage time showed no significant differences between hypertensive patients and reference values. Plasma viscosity was significantly increased in hypertensive patients and showed a significant increase with progression of the retinal changes. Hematocrit and erythrocyte aggregation were normal among the patients studied. The present findings show an alteration in blood fluidity among hypertensive patients, whereas retinal microcirculation showed no significant disturbances. Follow-up studies are planned to assess the development of retinal microcirculatory changes among hypertensive patients.

Adult↗
PubMed1992

Angiotensin II induces formation of the early growth response gene-1 protein in rat vascular smooth muscle cells.

The effect of angiotensin II (Ang II) on the early growth response gene-1 (Egr-1) mRNA, on the Egr-1 protein and on the phosphoinositide PI turnover signalling system was investigated in the presence and absence of EXP3174, a potent non-peptide Ang II receptor antagonist. Ang II induced an accumulation of 3.4 kb Egr-1 mRNA and the 80 kDa Egr-1 protein, with a maximum at 30 min and 60 min, respectively. EXP3174 blocked the Ang II-induced increase of inositol phosphates, Egr-1 mRNA and the Egr-1 protein, suggesting the involvement of the PI signalling system by the expression of the Egr-1 gene.

Angiotensin II↗
PubMed1992

[Retinal circulation and current blood glucose value in diabetic retinopathy].

In 42 type II diabetic patients with nonproliferative diabetic retinopathy the arm-retina time (ART) and arteriovenous passage time (AVP) were measured by means of videofluorescein angiography. Glycosylated hemoglobin (HbAlc) as a parameter of longterm diabetic control and the blood glucose level were determined. The ART in the diabetics was similar to the ART of normals and the AVP was significantly prolonged. HbAlc level ranged between 5.6 and 12.2% (8.6 +/- 1.7%) and the blood glucose level between 4.5 and 22.9 mmol/l (11.4 +/- 4.5 mmol/l). Significant correlations were found between AVP and blood glucose (r = 0.37) and between AVP and HbAlc (r = 0.49). No correlation was found neither between ART and blood glucose nor between ART and HbAlc. A multiple stepwise regression analysis shows that of both investigated parameters HbAlc is the predicting variable for AVP. These results show that in diabetic patients the retinal blood flow is more influenced by the longterm diabetic control than by the blood glucose level at the time of examination.

Aged↗
PubMed1991

Retinal blood flow in diabetic children and adolescents.

A total of 209 diabetic children and adolescents aged 6-17 years (mean, 12.6 +/- 2.3 years) were examined by ophthalmoscopy, video fluorescein angiography and hemoglobin (HbA1c) test. Microaneurysms were found in 26% of the children (ophthalmoscopy, 11%; angiography, 23%). The prevalence of retinopathy was 16% in patients aged 6-10 years, 27% in those aged 11-13 years and 36% in those aged 14-17 years. Only five diabetics aged 11-17 years showed lesions other than microaneurysms (hard exudates, intraretinal hemorrhages or retinal capillar leakage). Retinal blood flow was quantified using video fluorescein angiography. The arm-retina time (ART) and the arteriovenous passage time (AVP) as parameters of the retinal microcirculation were obtained using an image analysing system. The mean value for ART was 9.7 +/- 2.5 s and that for AVP was 1.43 +/- 0.52 s. AVP was significantly shorter in diabetic children and adolescents with good glycemic control (HbA1c, less than 7%; AVP, 1.35 +/- 0.44 s) than in those with bad glycemic control (HbA1c, greater than or equal to 9%; AVP, 1.65 +/- 0.51 s).

Adolescent↗
PubMed1991

[Hemodynamic findings in patients with retinitis pigmentosa].

The hemodynamic status of 26 patients with retinitis pigmentosa was examined using video fluorescein angiography. The hemorheological parameters hematocrit, plasma viscosity, erythrocyte aggregation and erythrocyte rigidity were determined. The results were compared to a matched pairs-group. Video angiography showed for retinitis pigmentosa patients a normal arm-retina time and a significant increase of the arteriovenous passage time. The rheological parameters for both groups were within the reference range. Interestingly the hemodynamic disturbance of microcirculation could be demonstrated already in early stages with no ophthalmoscopic symptoms and no atrophy of retinal vessels detectable at the time. The results indicate that disturbance of the retinal hemodynamics in early stages of retinitis pigmentosa may play a role in the pathogenesis of the disease.

Adolescent↗
PubMed1991

[Video fluorescein angiography studies in acute anterior ischemic optic neuropathy].

Acute anterior ischemic optic neuropathy (AION) is a circulatory disorder of the short posterior ciliary arteries and their branches. 74 patients with AION were examined with video fluorescein angiography for disturbance of the retinal circulation. The armretina time (ART) was slightly (15%, p less than 0.01) increased in patients with AION (12.9 +/- 3.9 s) as compared to healthy persons (11.2 +/- 3.3 s). The prolonged ART was more prominent in the 26 (35.1%) diabetic patients (14.2 +/- 3.9 s). Because of the ART being only moderately prolonged and since the Doppler ultrasonography of the carotid arteries showed in only 3 patients an occlusion or a hemodynamically relevant stenosis of greater than or equal to 50%, prolonged ART may play a considerable role in the course of AION in only few patients. The retinal arteriovenous passage time (AVP) is considerably (77%, p less than 0.01) increased in AION (2.57 +/- 0.89 s) as compared to healthy persons (1.45 +/- 0.40 s). In patients with duration of symptoms less than 10 days (2.78 +/- 0.96 s) the AVP was increased (p less than 0.01) as compared to patients with duration of symptoms between 11 and 30 days (2.11 +/- 0.46 s). The comparison between the eye with AION and the not affected eye showed no difference in ART but an increase of AVP in the eye with AION. The AVP in AION patients without and with diabetes was not different. No differences in ART and in AVP were found between arteriitic and non-arteriitic patients with AION. The results indicate that the retinal microcirculation is disturbed in patients with arteriitic and non-arteriitic AION. This condition may worsen the in AION affected microcirculation of the optic nerve head through the mechanism of decreased blood flow in the retinociliary anastomoses.

Aged↗
PubMed1991

Retinal circulation times in diabetes mellitus type 1.

Video fluorescein angiography was performed in 124 patients between 18 and 65 years of age (mean 35.0, SD 12.3 years) with juvenile-onset, insulin-dependent diabetes mellitus (type 1). The arm-retina time (ART) and the retinal arteriovenous passage time (AVP) were measured by means of a picture analysis system to quantify the retinal microcirculation. Glucose metabolism was assessed by the blood level of haemoglobin A1c. The ART 11.5, SD 3.4 s) was similar to that in normal persons (11.2, SD 3.3 s), while the AVP was significantly longer in the diabetics (AVP = 2.35, SD 0.87 s) than in normal persons (AVP = 1.45, SD 0.40 s). The patients with severe diabetic retinopathy showed the most impressive change in AVP. The diabetics with good glycaemic control, that is, with glycosylated haemoglobin (HbA1c) less than or equal to 8.0 g/dl, had a shorter AVP than patients with bad glycaemic control (HbA1c greater than or equal to 9.5 g/dl). The group with a history of diabetes for less than five years showed circulation parameters similar to those of normal persons. The AVP in this group was significantly shorter than in groups with a history of diabetes for five or more years.

Adolescent↗
PubMed1991

[Hemodilution in patients with central retinal vein thrombosis. A placebo-controlled randomized study].

A randomized placebo-controlled study was conducted in 40 patients with acute retinal vein occlusion, 19 of whom received iso-(Hct greater than or equal to 42%) or hypervolemic (Hct less than 42%) hemodilution over 10 days with daily infusion of 250 ml hydroxyethyl-starch (MW 200,000/0.5, 10% HAES-steril) in combination with pentoxifylline (oral: 1200 mg/day; i.v.: 300 mg/day; Trental). After this 10-day trial of hemodilution rheological therapy was continued with pentoxifylline (oral: 1200 mg/day; Trental). The control group of 21 patients received no hemodilution or rheological therapy. After 10 days 35 patients underwent laser coagulation. Clinical, hemodynamic and rheological data of all patients were recorded before therapy, after 10 days but before laser coagulation, and after 6 weeks. In the group treated with hydroxyethyl-starch in combination with pentoxifylline, 10 patients had an improvement of central vision by two or more lines after 6 weeks. In the control group only 4 patients showed central vision improved by two or more lines after 6 weeks. In the treated group the retinal circulation and rheological data were significantly improved after 10 days of hemodilution therapy.

Adult↗
PubMed1991

[Retinopathy as the first symptom of hairy cell leukemia].

Hairy cell leukemia is a seldom non-Hodgkin-lymphoma of the B-cells. The case of a 39 year old male with loss of vision as first sign of hairy cell leukemia is presented. The decrease of vision was caused by intraretinal bleeding into the macula. By means of ophthalmoscopy and angiography we found intraretinal bleedings, soft exudates, microaneurysms and capillary occlusions. The examination of blood cells showed leucocytosis (48.900/microliter), anemia (hemoglobin 8.7 g/l), thrombocytopenia (67.000/microliter) and hairy cells in peripheral blood and in bone marrow. Under treatment with alpha-Interferon visual acuity became normal and the fundus lesions decreased. This case points out that a retinopathy with bleedings and soft exudates can be caused by leukemia which should therefore be excluded by differential blood count.

Adult↗
PubMed1991

[Conjunctival microcirculation and hemorheology in patients with venous occlusions of the retina].

Forty-two patients with branch vein or central retinal vein occlusion were enrolled in this randomized placebo-controlled study. We studied the influence of hemodilution therapy with hydroxyethyl-starch (HAES-steril) combined with pentoxifylline (Trental) for 6 months. In the bulbar conjunctiva, capillary red blood cell (RBC) velocities and vessel diameters and rheological parameters of hematocrit, erythrocyte aggregation and plasma viscosity were examined. In the hemodilution group we observed no changes in vessel diameter and a significant increase in RBC velocity after therapy. After 6 weeks the RBC velocity showed 30% higher values but there was no statistically significant difference. After hemodilution therapy hematocrit, erythrocyte aggregation and plasma viscosity were significantly different from those in the control group. After 6 weeks we observed significant differences only in erythrocyte aggregation. This examination verifies the positive influence of hemodilution therapy on microcirculation and hemorheology.

Adult↗