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PubMed1977

[On the clinical picture of Handmann's anomaly of the optic nerve Morning glory syndrome? (author's transl)].

The author reports on the case of a 20-year-old patient who shows the characteristic changes of the central vessels, described by Handmann in 1929 to be a "herditary degeneration - ppresumably congenital and glial - of the optic nerve in which the central vessels are particularly involved". The optic papilla of about normal size is surrounded here by a slightly protruding ridge, which shows separate pigmentary sediments on its edge. The retinal vessels arise out of the depth in increased number on the edge of the papilla. An excavation of the papilla cannot be seen. In its place a whitish-yellow mass surrounded by grayish-pink colored tissue is evident, which obstructs the view into the deeper layers. Kinkler described very similar cases in 1970 and named the characteristic changes "morning glory syndrome". However, in the cases he described, the papillas were apparently greatley enlarged. In addition to the changes in the papillary area and the vessel structure in our case, there are definite changes in the macula (on both sides). Due to the conspicuous distribution of vessels within the papillary region in the father of the patient, similar to those found in Handmann's anomaly of the nerve, the author believes that he can safely assume a developmental disturbance of the origin of the retinal vessels of the papillary area in this case also and that therefore a hereditary component of this developmental disturbance could be described for the first time since Handmann in 1929. In the kin which the author examined, a further apparently familial renal hypoplasia was noted.

Adult↗

PubMed1994

Immunohistochemical insights into sickle cell retinopathy.

Dynamic vaso-occlusive and vaso-proliferative events occur in sickle cell retinopathy. Using streptavidin peroxidase immunohistochemistry, we investigated changes in distribution and relative levels of components in the fibrinolytic system and growth factors in retina and choroid from 2 sickle cell patients: a 20 month old SS patient and a 54 year old SC patient. Antigen localization in the sickle cell patients was compared to localization from 2 non-sickle cell, non-diabetic control subjects. In the fibrinolytic system, tissue plasminogen activator (tPA) localization and immunoreactivity were comparable in all eyes, but plasminogen activator inhibitor-1 (PAI-1) immunoreactivity was elevated within the walls of retinal vessels in the sickle cell tissue. Immunoreactive fibrin was often observed within the lumen of retinal and choroidal vessels and in choroidal neo-vascularization (CNV) in sickle cell subjects. Blood vessels containing fibrin generally exhibited elevated PAI-1 immunoreactivity. Von Willebrand's factor (vWf) and basic fibroblast growth factor (bFGF) immunoreactivity in sickle cell patients were elevated in choriocapillaris and the walls of some retinal vessels. Transforming growth factor-beta 1 (TGF-beta 1) immunoreactivity was significantly lower in sickle cell choriocapillaris than in controls. In chorioretinal pigmented lesions of the SC patient, bFGF and TGF-beta 1, beta 2, and beta 3 immunoreactivity was present within migrating retinal pigment epithelial (RPE) cells. Our interpretation of the data presented in this case study is that fibrin deposition within retinal and choroidal vessels of sickle cell subjects may occur due to elevated PAI-1 activity. Moreover, vaso-occlusions of choroidal vessels may influence the expression of growth factors in choriocapillaris endothelium, which could stimulate formation of choroidal neovascularization. Finally, fibrosis and gliosis in and near chorioretinal pigmented lesions may be stimulated by RPE production of bFGF and TGF-beta's.

Aged↗

PubMed1978

Choroidal melanoma clinically simulating a retinal angioma.

An amelanotic fundus lesion in a 35-year-old man was associated with a dilated retinal vessel, thus suggesting the diagnosis of retinal angioma. Fluorescein angiography and B-scan ultrasonography were not diagnostic, but a radioactive phosphorus uptake test suggested the lesion was malignant. The enucleated globe showed a malignant choroidal melanoma drained by a large retinal vein.

Adult↗

PubMed2000

Retinal expression, regulation, and functional bioactivity of prostacyclin-stimulating factor.

Prostacyclin-stimulating factor (PSF) acts on vascular endothelial cells to stimulate the synthesis of the vasodilatory molecule prostacyclin (PGI2). We have examined the expression, regulation, and hemodynamic bioactivity of PSF both in whole retina and in cultured cells derived from this tissue. PSF was expressed in all retinal cell types examined in vitro, but immunohistochemical analysis revealed PSF mainly associated with retinal vessels. PSF expression was constitutive in retinal pericytes (RPCs) but could be modulated in bovine retinal capillary endothelial cells (RECs) by cell confluency, hypoxia, serum starvation, high glucose concentrations, or inversely by soluble factors present in early vs. late retinopathy, such as TGF-beta, VEGF, or bFGF. In addition, RPC-conditioned media dramatically increased REC PGI2 production, a response inhibited by blocking PSF with a specific antisense oligodeoxynucleotide (ODN). In vivo, PGI2 increased retinal blood flow (RBF) in control and diabetic animals. Furthermore, the early drop in RBF during the initial weeks after inducing diabetes in rats, as well as the later increase in RBF, both correlated with levels of retinal PSF. RBF also responded to treatment with RPC-conditioned media, and this effect could be partially blocked using the antisense PSF ODN. We conclude that PSF expressed by ocular cells can induce PGI2, retinal vascular dilation, and increased retinal blood flow, and that alterations in retinal PSF expression may explain the biphasic changes in RBF observed in diabetes.

Animals↗

PubMed1993

The fractal geometry of proliferative diabetic retinopathy: implications for the diagnosis and the process of retinal vasculogenesis.

10 retinal vessel patterns with neovascularisation at or near the optic disk (NVD) from eyes of patients with diabetic retinopathy were compared with vascular patterns from 14 normal eyes. The vascular patterns were taken from low angle fundus photographs. After digitizing, the fractal dimensions were calculated by means of the density-density correlation function method. The fractal dimension was found to be significantly higher for vessel patterns with NVD [D = 1.845 +/- 0.056 (m +/- sd)] as compared with the normal control group (D = 1.708 +/- 0.073) (p < 0.001). The fractal dimension of 1.8 appears to be a cutoff value. Higher values may indicate proliferative changes. Under these conditions the sensitivity of the method for the detection of NVD > or = Grade 3 in the Early Treatment Diabetic Retinopathy Study (ETDRS) grading system is 90%. The presence of such NVD in an eye is a "high risk characteristic" for severe visual loss, which requires panretinal laser treatment. Fractal analysis is therefore a possible new strategy for computer assisted "automated" detection and quantification of proliferative diabetic retinopathy. The fractal dimension of the new vessels suggests possible mechanisms involved in retinal vasculogenesis.

Diabetic Retinopathy↗

PubMed1997

[Color Doppler ultrasonography in evaluation of intraocular lesions].

OBJECTIVE: To evaluate the value of color Doppler ultrasonography (CDU) in the diagnosis of intraocular lesions. METHODS: 82 cases of intraocular diseases were examined by high-resolution CDU (7.5 mHz), and the blood flow pattern was evaluated at the base of two-dimensional image. RESULTS: CDU might show the blood flow of retinal vessels in all 21 cases of retinal detachment, no blood flow could be detected in 21 of 22 vitreous hemorrhages and/or membranes, and only in one case with diabetic proliferative retinopathy did fine blood flow be seen. Intratumor blood flow with branchy pattern could be detected in 17 of 18 cases with choroidal melanomas and 3 of 4 cases with choroidal metastatic carcinoma, and spectral analysis revealed high-resistance, simulating arterial blood flow waves. In 5 cases with choroidal hemangioma, intratumor blood flow with filled or sparkled pattern was detected, and the spectral analysis revealed both arterial and venous blood flow waves. No blood flow in the lesion was detected in simulating benign lesions i.e. 5 choroidal hemorrhages and 2 subretinal hemorrhages. In 3 cases (4 eyes) with persistent hyperplastic primary vitreous (PHPV), CDU showed band-shaped arterial blood flow coursing from optic nerve disc to the posterior surface of the lens in the vitreous cavity. CONCLUSION: CDU is helpful in the differential diagnosis among retinal detachment, vitreous hemorrhage, vitreous membrane, malignant choroidal melanoma, choroidal metastatic tumor, choroidal benign lesion or hemangioma, PHPV and lesions with white pupil.

Adolescent↗

PubMed1975

Retinal opacification after blunt non-perforating concussional injuries to the globe. A clinical and retinal fluorescein angiographic study.

Fluorescein angiographic studies are reported on fifteen patients presenting with retinal opacification after blunt mechanical non-perforating injuries involving the eye. In patients who subsequently regained full visual function and in whom complete resolution of the retinal changes occurred, retinal fluorography carried out less than 24 hours after injury revealed no abnormal features. In cases with more prolonged visual disability, retinal fluorescein examinations may, however, reveal damage to the retinal pigment epithelium before this becomes apparent on routine ophthalmoscopy, or the existence of impaired perfusion through the retinal vessels. It is suggested, therefore, that retinal fluorescein angiography has a role in assessing the visual prognosis in patients presenting with traumatic retinal oedema.

Adolescent↗

PubMed1993

[Ophthalmological study of the M-strain stroke-prone spontaneously hypertensive rats (2). Retinal arteriolar changes in fluorescein angiogram].

Malignant or precocious stroke-prone spontaneously hypertensive rats show severe hypertensive fundus changes such as generalized narrowing, caliber irregularity, and tortuosity of retinal arterioles or retinal edema. In our previous studies, these changes were classified into four grades from 0 to 3 according to severity. In the present study, hypertensive fundus changes in these rats, such as generalized narrowing or caliber irregularity of retinal arterioles, were studied by comparing fluorescein angiographs with color fundus photographs. Fluorescein leakage was observed from retinal vessels in more than half the retinal arterioles with hypertensive caliber irregularity of grade 2. Pathological studies also showed irreversible changes in the retinal arterioles with hypertensive caliber irregularity.

Animals↗

PubMed1999

Tissue oxygen levels control astrocyte movement and differentiation in developing retina.

Astrocytes play a key role in the development of retinal vessels by detecting hypoxia in developing retina and secreting the hypoxia-induced angiogenic factor VEGF to induce vessel formation. The astrocytes which play this role are themselves spreading over the retina, just ahead of the growing vessels. To understand the mechanisms which keep astrocytes in this strategic 'just ahead' position we have studied the effects of hyperoxia and hypoxia on astrocyte differentiation and movement in situ in neonatal rat retina and in primary culture. Hyperoxia in situ inhibited the stellation of astrocytes, so that they persisted in a relatively unbranched form, which accumulated at the edge of their spreading population; hyperoxia permitted but did not accelerate migration. Conversely, hypoxia induced unstellated astrocytes to stellate within 6 h. If the hypoxia was abnormally severe, it caused the astrocytes to hyperstellate and slowed their spread. Astrocytes in primary culture did not change morphology or motility when challenged by hypoxia. When treated with medium conditioned by retina however, astrocytes became mobile and, if the medium was conditioned by hypoxic retina, became stellate. These results suggest that the oxygen released by retinal vessels maintains the mobility of astrocytes, via a diffusible factor released by other retinal cells. Conversely, naturally generated hypoxia of developing retina plays a triple role, inducing astrocytes to stellate, to end their migration and to produce VEGF, thereby inducing vessel formation. The induction of stellation is mediated by a diffusible factor released by other retinal cells. Thus hypoxia of the retina generated by neural maturation induces key events in both the differentiation of astrocytes and the formation of blood vessels.

Aging↗

PubMed2005

Retinal artery and vein diameters during pregnancy in diabetic women.

PURPOSE: To study systemic and retinal circulatory variables and vasoactive hormones during pregnancy in women with and without diabetes. METHODS: Prospective study of 45 women with type 1 diabetes and 6 healthy pregnant women, from the first trimester of pregnancy to half a year after delivery, by using a fundus photographic method of determining retinal vessel diameters. RESULTS: In diabetic women, the mean arterial blood pressure increased from 90.7 +/- 10.9 mm Hg (mean +/- SD) in the first trimester to 102.4 +/- 16.4 mm Hg in the third trimester, accompanied by retinal arteriolar constriction, from a mean diameter of 95.5 +/- 11.3 to 92.2 +/- 12.9 microm (P = 0.007), arteriolar constriction being prominent in nonsmokers, from 96.6 +/- 11.1 to 92.3 +/- 13.0 microm (P < 0.001; n = 38), but absent in smokers, from 89.2 +/- 11.5 to 92.0 +/- 13.6 microm (P = 0.28). Healthy nonsmoking women demonstrated an increase in blood pressure during pregnancy comparable to that in diabetic women, but the change in mean retinal arteriolar diameter, from 88.5 +/- 10.9 microm in the first to 91.6 +/- 10.2 microm in the third trimester, did not reach statistical significance (P = 0.38). Diabetic retinopathy levels increased during pregnancy, but the change in arteriolar diameter from the first to the third trimester did not correlate with retinopathy, arterial blood pressure, HbA(1c), or atrial natriuretic peptide. Plasma angiotensin II correlated positively with the change in arteriolar diameter in women who did not smoke (P < 0.05). After delivery, retinal vessel diameters returned to the first trimester range in all subgroups. CONCLUSIONS: From the first to the third trimester of pregnancy, blood pressure increased and retinal arteriolar diameter decreased in diabetic women, but the arteriolar constriction associated with pregnancy and systemic arterial blood pressure increase was remarkably absent in diabetic women who smoked tobacco before and during pregnancy. It is unknown whether smoking inhibits this vasoconstrictive response by deactivating mechanisms of physiological adaptation or by activating these mechanisms before the first trimester of pregnancy.

Adult↗

PubMedDate not supplied

[Characteristics of retinal vascular involvement in systemic lupus erythematosus].

Retinal vascular abnormalities were studied in 194 patients with systemic lupus erythematosus (SLE). All patients fulfilled the American Rheumatism Association criteria for SLE. The mean age of patients was 31.9 +/- 9.7 years (17-63 years), women falling ill 5 times more often than men. Retinal vascular abnormalities were found in 67 (34.5%) patients and were as follows: retinal angiopathy (80.6%), cotton-wool spots (10.4%), occlusion of central vein or its branches (3%), occlusion of a retinal artery branch (4.5%), and retinal vasculitis with extensive peripheral capillary nonperfusion and neovascularization (3%). In general, retinal vascular occlusions were found in 6.7% of all SLE patients and in 19.4% of SLE patients with retinal vascular changes. Retinal vascular occlusions in SLE patients were associated with the antiphospholipid syndrome. Retinopathy did not depend on systemic hypertension or duration of SLE but correlated with disease activity. Small retinal vessels were involved more often than large vessels (p < 0.0395) and arteries more often than veins (p = 0.0338). Visual outcomes were better in patients with cotton-wool spots than in those with severe retinal vaso-occlusive disease (0.92 +/- 0.09 and 0.15 +/- 0.13, respectively, p < 0.0000).

Adolescent↗

PubMed1989

Pseudoglaucomatous physiologic large cups.

Using planimetric analysis of stereoscopic optic disk photographs, we studied 21 optic nerve heads of 11 subjects who shared the common feature of optic cups that were larger than the mean + 2 S.D. within the normal population. A comparison of these findings to those of 571 normal optic disks and 706 optic nerve heads in eyes with chronic primary open-angle glaucoma showed the following morphologic characteristics: (1) abnormally large optic disk area (mean +/- S.D., 4.49 +/- 0.56 mm2), (2) large cup/disk ratios with the horizontal ratio (0.78 +/- 0.03) significantly (P less than .001) larger that the vertical (0.71 +/- 0.03), (3) increased incidence of cilioretinal arteries, (4) normal neuroretinal rim area (2.06 +/- 0.35 mm2), (5) normal neuroretinal rim configuration, inferiorly (0.43 +/- 0.08 mm) broader (P less than .001, Wilcoxon test) than superiorly (0.33 +/- 0.06 mm), smallest (P less than .0001) temporally (0.20 +/- 0.04 mm), (6) normal form of zone alpha (irregular hypopigmentation and hyperpigmentation) of the parapapillary chorioretinal atrophy with its widest extension in the temporal horizontal area, (7) no zone beta (visible large choroidal vessels and sclera), (8) normal caliber of the parapapillary retinal vessels, and (9) normal parapillary retinal nerve fiber layer. These characteristics are helpful in the differentiation of primary and secondary large cups.

Adult↗

PubMed1987

Modulation of experimental retinal vasculitis using dexamethasone, cyclosporin A, and prazosin.

The effects of dexamethasone, cyclosporin A and prazosin were investigated in an animal model of retinal vasculitis. Both dexamethasone and cyclosporin A reduced the clinical and pathological signs of disease when given from the day of disease onset. Prazosin, an alpha 1 adrenergic antagonist, was given during the period of disease induction and blocked fluorescein leakage from actively inflamed retinal vessels, but had little effect on the clinical and pathological signs of disease. This study demonstrates the feasibility of using this animal model for therapeutic trials of anti-inflammatory agents in retinal vasculitis. The effect of prazosin on reducing vascular leakage from retinal vessels has implications for the treatment of inflammatory macula oedema in human disease.

Animals↗

PubMed2003

Autoregulative behavior of retinal arteries and veins during changes of perfusion pressure: a clinical study.

PURPOSE: To investigate the autoregulative response of large retinal vessels to artificial reduction of perfusion pressure. METHODS: The diameters of a venous and an arterial segment (each approx.1.5 mm in length) in one eye of each of 13 healthy volunteers (age 54.5+/-18 years) were measured continuously using the Retinal Vessel Analyzer (Imedos, Weimar, Germany). The intraocular pressure (IOP; mean before examination 13.7+/-2.9 mmHg) was increased by 21.2+/-3.5 mmHg by means of a suction cup in order to produce a temporary reduction of the retinal perfusion pressure. The RVA measurements were taken for 2 min without artificial intervention (baseline), for 100 s during IOP elevation, and for up to 10 min after removal of the suction cup. RESULTS: A significant response of arterial and venous diameters to the provocation was found ( P<0.02, ANOVA). The arterial and venous responses were opposite: Whereas the artificially elevated IOP increased the arterial diameter by +1.9+/-4.5%, the venous vessel diameter decreased by -2.6+/-3.5% ( P<0.02, Mann-Whitney U-test). After normalization of the IOP the arterial diameter fell slightly below the baseline value, while the veins underwent temporary dilation by +5.9+/-3.3% ( P<0.001). The mean systemic blood pressure did not change significantly during the investigation. CONCLUSION: Retinal arteries and veins of healthy volunteers exhibited opposite autoregulative behavior in response to perfusion pressure changes. This is believed to be due to the different regulative functions of arteries and veins.

Blood Pressure↗

PubMed1984

Perfusion of occluded retinal veins in the cat's eye.

The organisation and adherence of a clot induced experimentally in the retinal vein of a cat was studied in vitro. For this purpose a retinal vein was treated in vivo with argon laser photocoagulation in 31 eyes, and each eye was removed at periods of time varying between 3 hours and 7 days after treatment. The freshly enucleated eye was then placed in a perfusion chamber with the cornea under a contact lens, and the retinal vessels were perfused under direct microscopic visualisation. It appears that the hydrostatic pressure and flow needed to perfuse the obstructed vein has to be increased with elapsing time, and that 7 days after laser treatment the retinal vessel becomes permanently occluded.

Animals↗

PubMed2005

Retinal perfusion response to a slow multifocal M-sequence flicker stimulation.

PURPOSE: To assess, if a slow multifocal stimulus (mfS) can provoke a perfusion response that can be measured with the Retinal Vessel Analyzer (RVA). METHODS: Seventeen eyes were examined. Pupils were dilated. A 120-second baseline recording was obtained with the RVA. The subject then turned to view an mfS for 56 s. The mfS consisted of 103 hexagons flickering according to an m-sequence with a stimulus base interval of 53.3 ms (L(max) = 100 cd/m(2), L(min) < 1 cd/m(2)). Immediately thereafter, the subject turned to the RVA, where measurements were resumed as soon as the same retinal vessel was targeted and continued for 104 s. Stimulation and recording was repeated twice. The diameter of a retinal vein and artery was measured for a length of at least 1 mm. The maximum vessel response was obtained by linear interpolation of the measured response within the 20 s following mfS. RESULTS: On average, veins dilated by 6.8% and arteries by 7% following mfS (p > 0.005). Such a dilatation could be observed in 9 veins and 7 arteries. Three venous and 2 arterial measurements did not show a dilatation following mfS. However, 13 of 34 measurements could not be analyzed due to signal problems or because the time from the end of mfS and the uptake of measurement exceeded 20 s. CONCLUSION: This slow multifocal ERG stimulus results in a dilatation of arteries and veins that can be measured with the RVA. Coupling an mfS to the RVA has the potential to topographically map changes in retinal perfusion in relation to the respective retinal area stimulated. When implementing the mfS into the RVA setup in order not to lose time due to the refixation in the RVA following mfS, one is required to take the transient nature of this perfusion change into consideration.

Adult↗

PubMed2006

On pulse-wave propagation in the ocular circulation.

PURPOSE: To measure the oscillation phase delay between retinal arterioles and venules in order to analyze pulse wave propagation in the ocular circulation of vasospastic and nonvasospastic subjects and a change thereof during the cold pressor test in another group of healthy subjects. METHODS: Twenty-four young, healthy women, 12 vasospastic and 12 nonvasospastic, were analyzed. A retinal vessel analyzer was used to obtain 1-minute recordings of the ocular fundus. A phase delay between the arteriole and venule pulsations was assessed at three sites, one (proximal) in the close retinal vicinity of the disc, one (middle) 1 to 2 disc diameters away from the disc, and a third (distal) 3 to 4 disc diameters away from the disc; and, assuming that venules are counterphased to the choroidal circulation, a choroid-to-retina pulse delay was calculated. In addition, the change in these parameters was analyzed during the modified cold-pressor test in 10 healthy subjects (five women, five men). RESULTS: Pulse oscillations in arterioles led those in venules by 95.0 degrees +/- 39.0 degrees , 60.5 degrees +/- 57.5 degrees , and 47.5 degrees +/- 64.0 degrees in vasospastic subjects, and 76.0 degrees +/- 58.0 degrees , 31.5 degrees +/- 60.0 degrees , and 2.5 degrees +/- 80.5 degrees in nonvasospastic subjects in the proximal, middle, and distal measuring sites, respectively. Calculated choroid-to-retina pulse delays in vasospastic subjects were 0.20 +/- 0.10, 0.28 +/- 0.14, and 0.30 +/- 0.11 seconds and in nonvasospastic subjects 0.25 +/- 0.15, 0.35 +/- 0.11, and 0.43 +/- 0.2 seconds at the proximal, middle, and distal measuring sites, respectively. The difference was significant between vasospastic and nonvasospastic subjects (P = 0.033) and among the measuring sites (P = 0.0023). During exposure to cold, the choroid-to-retina pulse delays changed from 0.31 +/- 0.08, 0.40 +/- 0.16, and 0.51 +/- 0.26 seconds to 0.26 +/- 0.12, 0.30 +/- 0.10, and 0.33 +/- 0.14 seconds at the proximal, middle, and distal measuring sites, respectively (P = 0.024 for the change from baseline to cold exposure, and P = 0.022 for measuring sites). CONCLUSIONS: Retinal vessels in vasospastic subjects demonstrate an altered pattern of oscillation phase delay between arterioles and venules. Vessels in vasospastic subjects seem to conduct pulse waves faster and are thus stiffer than those in nonvasospastic subjects. The pattern of oscillation demonstrates changes during the cold pressor test in healthy subjects, indicating faster pulse-wave propagation.

Adult↗

PubMed1984

[Fat embolism of retinal arteries following acute pancreatitis].

Fat embolism is well known in traumatic skull fractures, chest compression and long bone fractures. Inkeles and Walsh (1975) first described fat embolism of retinal vessels following acute pancreatitis. Fat embolism of ocular vessels in this disease is presumably due to enzymatic destruction of omental tissue. The patient described here fell ill with acute pancreatitis after years of alcohol abuse; he noticed a considerable deterioration in vision. This was a result of fat embolism of the retinal arteries. Multiple cotton wool spots around the optic nerve and in the macular area, combined with some intraretinal hemorrhages, were seen at ophthalmoscopic examination. The pathogenesis of fat embolism of choroidal and retinal vessels following acute pancreatitis is discussed in brief.

Acute Disease↗