Biomedical subjects

J Flammer

Publications and source records attributed to J Flammer.

248 records · Page 14Linked to original sources

PubMedDate not supplied

Connective tissue growth factor in retrocorneal membranes and corneal scars.

We studied the localization and distribution of connective tissue growth factor (CTGF) in corneal scar tissue and membranes using in situ hybridization in 8 corneas from keratoplasty and 4 normal corneas. Identification of the cells was done with immunohistochemistry for SM-alpha-actin, vimentin, and Lu5. CTGF mRNA was found in activated corneal fibroblasts in 7 of 8 scars, 7 of 8 retrocorneal membranes and 2 subepithelial membranes, whereas the control corneas showed no CTGF mRNA expression. Vimentin was positive in all scars, retrocorneal and subepithelial membranes, SM-alpha-actin in 7 of 8 scars and 6 of 8 retrocorneal membranes. These results suggest that CTGF plays a crucial role in corneal wound healing and membrane formation.

Actins↗

PubMedDate not supplied

Perioperative posterior ischemic optic neuropathy as a rare complication of blepharoplasty.

PURPOSE: To report a case of visual loss to light perception in the right eye after upper and lower eyelid blepharoplasty. DESIGN: Case report. METHOD: A 46-year-old man was referred 3 days after combined bilateral upper and lower lid blepharoplasty with visual acuity of light perception in the right eye. The fundus examination, fluorescein angiography and magnetic resonance imaging of the orbit were normal. Ocular motility was full in all directions of gaze. RESULT: The diagnosis of optic nerve damage was initially based on the relative afferent pupillary defect. The diagnosis of a perioperative posterior ischemic optic neuropathy was based on the Goldmann visual field examination and the subsequent optic atrophy. Central visual acuity, color vision as well as the visual field improved markedly within 3 months. CONCLUSION: Blindness is a rare but feared complication of blepharoplasty and is reported to occur in about 0.04% of cases. Although intraorbital hemorrhage is thought to be the leading cause for optic nerve damage in most of the patients with this devastating condition, we present a case with perioperative posterior ischemic optic neuropathy leading to visual loss after blepharoplasty. The mechanism leading to optic nerve damage in this patient may include compromised small arteries perfusing the optic disk due to direct mechanical compression and a probable vasoconstrictive activity of the anesthetic agent.

Blepharoplasty↗

PubMedDate not supplied

Short- and long-term effect of nifedipine on the visual field in patients with presumed vasospasm.

It is assumed that the ocular circulation may be involved in the vasospastic syndrome and patients with vasospasm have visual field defects that are neither ophthalmologically nor neurologically explainable. A retrospective study showed that 20 mg sustained-release nifedipine treatment given orally may be helpful in these cases. There was a marked short-term effect in cases with proven peripheral vasospasms but not in similar cases without such vasospasms. The study also showed that the effect could last for up to 12 months when 20 mg nifedipine was given twice daily but the long-term effect was slightly less than the short-term effect. A number of patients had to discontinue nifedipine treatment due to side-effects.

Adolescent↗

PubMedDate not supplied

Bilateral non-arteritic anterior ischemic optic neuropathy in a patient with autoimmune thrombocytopenia.

PURPOSE: To describe a patient with bilateral non-arteritic anterior ischemic optic neuropathy (NAION) and idiopathic autoimmune thrombocytopenia (ITP) with an extremely low platelet count. METHOD: Case report. RESULTS: Remarkably good recovery of visual acuity. CONCLUSIONS: Bilateral non-arteritic anterior ischemic optic neuropathy can develop in the presence of a very low platelet count.

Aged↗

PubMedDate not supplied

Susac syndrome: a vasospastic disorder?

PURPOSE: The Susac syndrome is a microangiopathy that leads to visual symptoms, hearing loss and neurological symptoms. CASE REPORT: We report on a young woman suffering from this syndrome who also presented the following signs and symptoms typical of a vasospastic syndrome; 1) a history of cold hands, low blood pressure and migraine; 2) a typical alteration of conjunctival vessels; 3) prolonged flow arrest time after cooling in nailfold capillaromicroscopy; 4) increased resistivity in the orbital vessels measured by color Doppler imaging; and 5) an increased plasma level of endothelin-1. CONCLUSIONS: We postulate that the Susac syndrome is a manifestation of the vasospastic syndrome.

Adult↗

PubMedDate not supplied

Influence of carteolol and timolol on IOP an visual fields in glaucoma: a multi-center, double-masked, prospective study.

The influences of Carteolol and Timolol eye drops on intraocular pressure (IOP) and visual fields were compared in a multi-center, double-masked, prospective study. Two-hundred and forty eyes of 120 patients were initially included in the study, and 142 eyes of 72 patients fulfilled all the criteria for final statistical analysis. Both drugs significantly reduced IOP. The visual fields in both treatment groups did not change during one year of treatment. In both groups some patients improved slightly, and others deteriorated slightly. This indicates that locally applied beta-blockers may efficiently stop further progression of visual field defects in cases with increased IOP and early visual field damage. There was no difference between Carteolol and Timolol in this regard. The side effects were minimal, and there were no differences in their frequency or intensity in the two treatment groups.

Adolescent↗

PubMedDate not supplied

Relationship cataract density and visual field damage.

In interpreting visual field results, two questions arise: a) what type of visual field damage is produced by cataract, and b) can the influence on the visual field somehow be predicted? To answer these questions, cataract density was quantified with the Opacity Lens Meter (OLM) 701, and visual field tests were done before and after IOL-implantation surgery with Octopus Program G1 in 58 eyes of 58 patients (mean age 71 +/- 8 years) with cataract but with no other detectable ocular diseases. The average improvement of mean damage (MD) after surgery was 5.4 dB, and that of D (20) (defect 20 on the Bebie Curve) was 5.7 dB. The improvement of the visual fields was, as expected, statistically highly significant (p < 0.0001). The corrected loss variance (CLV), however, increased on the average only by 2.5 dB2, which was not significant. The predictive value of the OLM reading for opacity-induced MD depends on the type of cataract. It is good for cortical and nuclear cataracts but poor for posterior subcapsular opacifications. The overall predictive value (R = 0.66) is, nevertheless, better than for preoperative visual acuity (R = -0.54). If OLM and visual acuity (VA) are considered together, the predictive value is slightly higher (R = 0.72). Thus, optical density influences on visual field performance can be subtracted from general visual field results.

Adult↗

PubMedDate not supplied

Influence of nifedipine on the visual fields of patients with optic-nerve-head diseases.

Calcium-channel blockers have long been employed in coronary disease, and recent investigations have indicated their efficacy in improving the visual field in low-tension glaucoma or presumed vasospasm, possibly by enhancing ocular circulation. We evaluated the short-term influence of a typical calcium-channel blocker, nifedipine, on 59 patients with visual-field defects, some with optic-nerve-head pathology (n = 38) and some with normal-appearing optic nerve heads (n = 21). On the average, a statistically significant improvement of 1.2 dB was observed. Different types of patients, however, behaved quite differently. The younger the patient, the greater the improvement. Patients with normal optic nerve heads improved by 1.54 dB, whereas patients with optic-nerve-head excavation improved by only 0.66 dB. No response was observed in patients with anterior ischemic neuropathy. Marked deterioration was noted in one glaucoma patient with low systemic blood pressure. The visual-field changes were observed in the scotomatous and non-scotomatous areas. Thus, the calcium-channel blocker nifedipine can be effective in some selected diseases whose pathogenesis probably involves vascular dysregulation though it may even be contraindicated in others.

Glaucoma↗

PubMedDate not supplied

Interocular visual-field and intraocular-pressure asymmetries in normal-tension-glaucoma.

To evaluate the role of intraocular-pressure (IOP) in the pathogenesis of glaucomatous damage in normal-tension-glaucoma, we investigated whether the eye with the higher IOP had more severe visual-field damage in 23 normal-tension-glaucoma patients. Twelve patients did have more severe visual-field defects in the eye with the higher IOP, but 11 had more severe defects in the eye with the lower IOP. There was no correlation either between IOP and visual-field damage (r = 0.16; p = NS) or between the interocular differences in IOP and in visual-field damage (r = 0.21; p = NS). Thus, although intraocular pressure may contribute to glaucomatous damage even in normal-tension-glaucoma patients, other factors must be involved as well.

Adult↗

PubMedDate not supplied

Individual measurements of angiotensin II concentrations in aqueous humor of the eye.

The presence of constituents of the renin-angiotensin system (RAS) in ocular tissues and fluids suggests this system is involved in ocular physiology. Angiotensin II (AngII) is the main biological effector of the system, so we measured AngII in plasma and in aqueous humor of the anterior ocular chamber of patients undergoing cataract extraction. Untreated normotensive patients were compared with arterial hypertensive patients taking either diuretics which stimulate the RAS or angiotensin converting enzyme (ACE) inhibitors which reduce the production of AngII. Plasma levels of AngII were higher in patients on diuretics (5.46 +/- 1.04 fmol/ml; mean +/- SEM) than in untreated cataract patients (2.28 +/- 0.32 fmol/ml, p < 0.02), and were very low with ACE inhibitors (0.51 +/- 0.18 fmol/ml). In aqueous humor, AngII was measurable in 7 of 11 patients on diuretics (median 1.1 fmol/ml), and in 6 of 16 normotensive patients (median < 0.55 fmol/ml), but not in aqueous humor of 4 patients receiving enalapril or captopril. These results demonstrate the presence of AngII in the eye but do not exclude either its sequestration in the eye or local production. The possibility of individual measurements of intraocular AngII will permit more precise determination of its role in future studies.

Aged↗

PubMedDate not supplied

Systemic blood pressure and capillary blood-cell velocity in glaucoma patients: a preliminary study.

Systemic hypotension and vasospasm have both been suggested as risk factors for glaucomatous damage. Furthermore, a relationship between the incidence of vasospastic disorders and systemic hypotension has been reported. This preliminary study investigated the relationship between these two risk factors. In 20 glaucoma patients suspected to have vascular risk factors, time of blood-flow standstill was measured under cold provocation in nailfold capillaries and 24-hour blood pressure was monitored. Nine were high-tension glaucoma patients but progressing despite medically well-controlled intraocular pressure, and 11 had normal-tension glaucoma. Thirteen patients were vasospastic, and seven were not. Patients without vasospasm had a significantly lower mean systolic blood pressure during the daytime (113.4 +/- 7.1 mmHg) than vasospastic patients (122.6 +/- 12.8 mmHg), p = 0.026. The time of blood-flow standstill in vasospastic patients, however, correlated with the lowest individual systolic blood pressure reading (r = -0.56; p = 0.049). These low readings occurred mostly during the night ("deepers").

Blood Flow Velocity↗

PubMedDate not supplied

A new angiotensin-II- receptor blocker, CGP 48933: local tolerance and effect on intraocular pressure. A pilot study.

CGP 48933, a new angiotensin-II-receptor antagonist, has been shown to lower intraocular pressure (IOP) in two different rabbit glaucoma models in a dose-dependent manner after local application. As a further step a pilot study was performed in human eyes. The trial consisted of three parts. Parts 1 and 2 comprised a double-masked intraindividual trial between CGP 48933 and its vehicle (saline) in five healthy volunteers (Part 1) and five patients with early stages of primary open-angle glaucoma (Part 2), to assess local tolerance and the effect on IOP. Part 3 was a single-masked intraindividual trial between CGP 48933 and saline, to find the effective dose range of the new compound. Local tolerance was assessed as excellent in all subjects. No conjunctival hyperemia burning or itching occurred. There were no significant changes in IOP from baseline in drug or vehicle-treated eyes. In addition, there was no dose-dependent (200 micrograms to 1 mg) effect of CGP 48933 on IOP. Systemic blood pressure, heart rate and pupil size did not change during the observation period. Topical application of CGP 48933 in its present formulation is thus not suitable for lowering IOP in humans.

Administration, Topical↗

PubMedDate not supplied

Variations in the blood flow of the human optic nerve head.

Blood flow in various tissues of the body shows spontaneous variations. The purpose of this study was to analyze variations over time in the blood flow of the optic nerve head. Blood flow was measured by the laser Doppler flowmeter (LDF) in 12 healthy volunteers, and analyzed by spectral Fourier analysis. The LDF technique allows continuous measurement of flow, volume, and velocity in the microcirculation of the optic nerve head. We found variations expressed in cycles per minute (c/min) at frequencies characteristic of vasomotion (< 10 c/min) of breathing, and of cardiac pulsation. Oscillations at frequency < 10 c/min predominated in volume in all subjects and in flow in all but one. Variations in velocity of 60-90 c/min were identified in 10 of the 12 volunteers. Oscillations in the range of breathing frequency made the smallest contribution to changes in blood flow. Fluctuations in the frequency range of 5 c/min and lower were observed most frequently, and the majority of subjects showed fluctuations of several frequencies. Our results provide evidence that blood flow in the human optic nerve head presents some characteristics already known from the general physiology of the microcirculation.

Adult↗

PubMedDate not supplied

Heidelberg retina flowmeter parameters at the papilla in healthy subjects.

PURPOSE: To assess the Heidelberg Retina Flowmeter (HRF) parameters "volume", "flow", and "velocity", at the papilla in healthy subjects. METHODS: HRF measurements were taken at the papilla (5 degrees x 20 degrees), superficially at level of the retina and at the bottom of the excavation. The effect of increasing frame size (1 x 1 to 50 x 50 pixels) on HRF values was assessed in ten subjects. HRF parameters were calculated (50 x 50 pixels) for 150 eyes of 150 subjects. To assess short-term reliability, measurements were repeated five times in ten subjects. RESULTS: With 50 x 50 pixels the location of the frame had no influence on HRF values. Reliability was > 90%. Values were significantly higher (p < 0.001) in the superficial than in the deeper papillary layers. The correlation between HRF parameters was good (r2 > 0.85). CONCLUSIONS: A low magnification (5 degrees x 20 degrees) and a 50 x 50 frame allows a global assessment of HRF parameters at the papilla with high reliability. In healthy eyes, the HRF values are influenced by the level where measurements are made at the papilla. This might be of importance in glaucoma patients with excavated papilla.

Blood Flow Velocity↗