The effect of nifedipine on retinal venous pressure of glaucoma patients with the Flammer-Syndrome.

PURPOSE: The purpose was to measure the retinal venous pressure (RVP) in both eyes of primary open-angle glaucoma (POAG) patients before and 3 weeks after treatment with low-dosed Nifedipine. METHODS: This retrospective study included 20 POAG patients who were treated with Nifedipine (5 mg daily) and 20 untreated control POAG patients. In both the treated and untreated control group, a distinction was made between those patients who had the Flammer-Syndrome (FS) and those who did not. The RVP was measured in all patients bilaterally at baseline and 3 weeks later by means of contact lens ophthalmodynamometry and the RVP measurements of the treated POAG patients were compared to the RVPs of the untreated POAG controls. Ophthalmodynamometry is done by applying an increasing force on the eye via a contact lens. The minimum force required to induce a venous pulsation is called the ophthalmodynamometric force (ODF). The RVP is defined and calculated as the sum of ODF and intraocular pressure (IOP) [RVP = ODF + IOP]. RESULTS: The RVP decreased significantly after 3 weeks in both eyes of patients treated with low-dosed Nifedipine compared to the untreated group (mean decrease of 12.5 mmHg (SD 12.5), P < 0.001). A larger response to therapy was found in patients with the FS compared to patients lacking the FS (mean decrease of 16.07 vs. 7.28 mmHg, confidence Interval (CI): 5.2 to 9.3 vs. 12.3 to 19.7; P < 0.001). No significant differences were accounted for in the IOP's of the patients after treatment. In the untreated control group, no significant differences were accounted for either in the RVP or the IOP after 3 weeks. CONCLUSIONS: Treatment with low-dosed Nifedipine decreases RVP in both eyes of glaucoma patients, particularly in those with the Flammer-Syndrome. This effect may be due to the partial inhibition of Endothelin-1 (ET-1) by Nifedipine.

Retinal venous pressure in the non-affected eye of patients with retinal vein occlusions.

BACKGROUND: To measure the retinal venous pressure (RVP) in both eyes of patients with unilateral central retinal vein occlusions and to compare these values to controls. METHODS: The study included 31 patients with unilateral central retinal vein occlusions (CRVO) and 31 controls who were matched by age, sex, and systemic disease. RVP was measured in all patients bilaterally by means of contact lens ophthalmodynamometry, and the RVP measurements of the affected and unaffected eyes of patients were compared to the RVPs of controls. Ophthalmodynamometry is done by applying an increasing pressure on the eye via a contact lens. The minimum force required to induce a venous pulsation is called ophthalmodynamometric force (ODF). The RVP is defined and calculated as the sum of ODF and intraocular pressure (IOP) [RVP = ODF + IOP]. RESULTS: The RVP group means ± SD were as follows: patient's affected eyes (45.0 ± 11.6 mmHg), patient's unaffected eyes (38.0 ± 11.1 mmHg) ,and (17.7 ± 6.7 mmHg) in the eyes of controls. The values of RVP, even in the patients unaffected eyes, were significantly higher than in the eyes of controls (P < 0.001). CONCLUSIONS: In patients with CRVO, the RVP is increased in both the affected as well as in the unaffected contralateral eye.

The effect of flammer-syndrome on retinal venous pressure.

BACKGROUND: The purpose of the study was to measure the retinal venous pressure (RVP) in the eyes of primary open-angle glaucoma (POAG) patients and healthy subjects with and without a Flammer-Syndrome (FS). METHODS: RVP was measured in the following four groups of patients and age- and sex-matched healthy controls: (a) 15 patients with a POAG and a FS (POAG/FS+); (b) 15 patients with a POAG but without a FS (POAG/FS-); (c) 14 healthy subjects with a FS (healthy/FS+) and (d) 16 healthy subjects without a FS (healthy/FS-). RVP was measured in all participants bilaterally by means of contact lens ophthalmodynamometry. Ophthalmodynamometry is done by applying increasing pressure on the eye via a contact lens. The minimum force required to induce a venous pulsation is called ophthalmodynamometric force (ODF). The RVP is defined and calculated as the sum of ODF and intraocular pressure (IOP) [RVP = ODF + IOP]. RESULTS: The participants with a FS (whether patients with POAG or healthy subjects), had a significantly higher RVP compared to subjects without a FS (p = 0.0103). Patients with a POAG and FS (POAG/FS+) had a significantly higher RVP compared to patients without a FS (POAG/FS-) (p = 0.0301). There was a notable trend for a higher RVP in the healthy/FS + group compared to the healthy/FS - group, which did not reach statistical significance (p = 0.0898). CONCLUSIONS: RVP is higher in subjects with a FS, particularly in glaucoma patients. The causal relationship needs to be further evaluated.

Smell perception in normal tension glaucoma patients.

PURPOSE: The aim of this study was to quantify the ability to identify odors in normal tension glaucoma (NTG) patients and healthy subjects with and without a primary vascular dysregulation (PVD). METHODS: Both self-assessment of smell perception and evaluation of odor identification by means of the 12-item odor identification test ("Sniffin' Sticks") were performed in the following groups of subjects: 1) 18 NTG patients with PVD (G+), 2) 18 NTG patients without PVD (G-), 3) 18 healthy subjects with PVD (H(+)) and 4) 18 healthy subjects without PVD (H-). The subjects self-assessment of smell perception was evaluated before the Sniffin' Sticks test by asking them to judge their ability to identify odors as either "average," "better than average," or "worse than average." RESULTS: Subjects with a PVD (G+ and H(+)) can identify odors significantly better than those without a PVD (G- and H-; in a score scale of 1-12 the score point difference=2.64, 95% CI=1.88-3.40, p<0.001). No significant differences in odor identification was found between NTG (groups G+ and G-) and healthy subjects (groups H(+) and H-; score point difference=-0.14, 95% CI=-0.9-0.62, p=0.72). CONCLUSIONS: Subjects with a PVD can identify odors significantly better than those without a PVD.

Thermal discomfort with cold extremities in relation to age, gender, and body mass index in a random sample of a Swiss urban population.

BACKGROUND: The aim of this epidemiological study was to investigate the relationship of thermal discomfort with cold extremities (TDCE) to age, gender, and body mass index (BMI) in a Swiss urban population. METHODS: In a random population sample of Basel city, 2,800 subjects aged 20-40 years were asked to complete a questionnaire evaluating the extent of cold extremities. Values of cold extremities were based on questionnaire-derived scores. The correlation of age, gender, and BMI to TDCE was analyzed using multiple regression analysis. RESULTS: A total of 1,001 women (72.3% response rate) and 809 men (60% response rate) returned a completed questionnaire. Statistical analyses revealed the following findings: Younger subjects suffered more intensely from cold extremities than the elderly, and women suffered more than men (particularly younger women). Slimmer subjects suffered significantly more often from cold extremities than subjects with higher BMIs. CONCLUSIONS: Thermal discomfort with cold extremities (a relevant symptom of primary vascular dysregulation) occurs at highest intensity in younger, slimmer women and at lowest intensity in elderly, stouter men.

Relationship between optic nerve head and finger blood flow.

PURPOSE: To examine the relationship between optic nerve head (ONH) and finger blood flow in subjects with and without a primary vascular dysregulation (PVD). METHODS: ONH blood flow and finger blood flow was measured in 15 subjects with PVD and in 24 subjects without PVD. PVD was defined as being present if it was detected in patient history as well as by nailfold capillaromicroscopy. PVD was defined as being absent if the patient history for PVD was negative and the results of nailfold capillaromicroscopy were negative. Scanning laser Doppler flowmetry (LDF) was used to measure ONH and finger blood flow. Finger temperature was measured in all subjects using a contact sensor. RESULTS: ONH blood flow is significantly related to finger blood flow in subjects with PVD (p<0.01), but not in subjects without a PVD. Subjects with PVD had a significantly lower finger skin temperature in comparison to those without PVD (p<0.01) CONCLUSIONS: The present study indicates a relationship between ONH and finger blood flow in subjects with PVD. This might be an indirect sign of a disturbed autoregulation of ocular blood flow in PVD subjects.

Second eye cataract surgery in the diabetes patient? Quality of life gains and speed of visual and functional rehabilitation.

PURPOSE: To assess gains in quality of life (QOL) and visual acuity (VA), and to evaluate speed of visual and functional rehabilitation in diabetes patients with different stages of retinopathy (DR) after phacoemulsification in either one or both eyes. METHODS: This prospective longitudinal study comprised 102 patients having either (1) first eye, or (2) first and subsequent second eye cataract surgery. One surgeon performed all surgeries. In both groups, the following subset of patients was compared: those with no apparent retinopathy (no DR), those with mild nonproliferative DR (NPDR), those with severe NPDR, and those with proliferative DR. VA and questionnaire (VF-14) responses were recorded prior to and 1, 3, 6, 8 and 12 months after surgery. RESULTS: Patients with no DR and mild NPDR showed a significantly more rapid speed of visual and functional rehabilitation compared to patients with severe NPDR and proliferative DR. Maximum visual and functional results for these patients were observed 1 month after surgery, and values were significantly higher in comparison to other patients (p values <0.0001). Patients with no DR and mild NPDR who had second eye surgery demonstrated significant improvements (VA, QOL) and sustainment of the improved functional status achieved after first eye surgery (p<0.001). CONCLUSIONS: Patients with no DR and mild NPDR show greater significant improvements in QOL and VA, and a more rapid speed of visual and functional rehabilitation in comparison to patients with more advanced DR. Functional gains are sustained at 1 year after surgery, if second eye surgery is performed.

Oxygen and blood flow: players in the pathogenesis of glaucoma.

UNLABELLED: The increase of IOP in POAG is due an increased resistance of aqueous outflow through the trabecular meshwork (TM). The exact mechanisms leading to the corresponding changes in the TM are not yet known. We know, however, that all risk factors for arteriosclerosis are also risk factors for an increase in IOP. RESULTS: The association between IOP increase and these factors is relatively weak but nevertheless significant. Similar to the pathogenesis of arteriosclerosis, oxidative stress plays a role in the development of TM damage. Even less is known about the pathogenesis of glaucomatous optic neuropathy (GON). Obviously the risk factors for arteriosclerosis play a role via increasing the IOP. When corrected for IOP, however, these factors only play a minor role. In contrast, factors associated with disturbed autoregulation, in particular a systemic primary vascular dysregulation (PVD), increase the risk for GON. This is best observed in normal tension glaucoma patients. An insufficient autoregulation increases the chance for an unstable ocular perfusion and thereby an unstable oxygen supply. This, in turn, leads to oxidative stress. The concentration of superoxide (O(2)(-)) within the axons of the optic nerve head increases. If neighboring astrocytes are activated, either by mechanical or by ischemic stress, in excess produced nitric oxide (NO) molecules diffuse also into the axons and fuse with oxygen. The resulting peroxynitrat (ONOO(-)) diffuses within the axons towards the retina and the lateral geniculate nucleus and induces apoptosis.

Subretinal hemorrhages secondary to age-related macular degeneration: psychological and vision-related functional perspectives.

PURPOSE: To assess psychological, visual and functional aspects associated with subretinal hemorrhages secondary to age-related macular degeneration (AMD). METHOD: In this prospective, comparative, longitudinal study, 90 eyes of 90 patients with a subretinal hemorrhage, secondary to AMD, of at least 1 disk diameter were treated with recombinant tissue plasminogen activator (rTPA) and gas, and compared to 25 eyes of 25 controls. Outcome measures were: (1) visual acuity, (2) self-reported vision-related quality of life (Visual Function 14-item questionnaire) and (3)Hospital Anxiety and Depression (HAD) scores. Visual acuity and questionnaire responses were recorded prior to as well as 2 weeks and 4 months after treatment. RESULTS: Improvements across objective visual acuity and vision-related functional measures, assessed at 2 weeks and 4 months, were significantly higher in patients who had rTPA and gas injections than in controls (p < 0.01). Patients were significantly more distressed at their 2-week follow-up in comparison to controls (HAD scores p < 0.01). Comparisons to controls showed no significant difference in psychological scores at the 4-month follow-up (p > 0.32). CONCLUSIONS: Patients with subretinal hemorrhages secondary to AMD are psychologically distressed as a result of acute loss of vision. More attention should be given to strategies that teach patients to cope with acute vision loss and thereby psychological disorder.

Autoregulation, a balancing act between supply and demand.

Regulation of blood flow is necessary to adapt to different conditions. Regulation of ocular blood flow (OBF) compensates for varying perfusion pressures (autoregulation), adapts to the retinal activity (neurovascular coupling), and keeps the back of the eye at constant temperature (thermoregulation). While all vessels are under the control of the vascular endothelial cells, the retinal vessels are additionally under the control of the neural and glial cells, and the choroidal vessels are influenced by the autonomic nervous system. The optic nerve head is additionally controlled by circulating hormones. If the regulation does not occur according to the needs of the tissue, it is referred to as vascular dysregulation. Such a dysregulation can be secondary in nature, as, for example, in multiple sclerosis, in which the high level of endothelin reduces OBF. Dysregulation, however, can also occur without any underlying disease and is characterized by an inborn tendency to respond differently to various stimuli, such as cold temperatures or mechanical or emotional stress. The constellation of these features is known as primary vascular dysregulation (PVD). Subjects with PVD have disturbed autoregulation leading to an unstable OBF. This instability, in turn, induces a repeated mild reperfusion injury. The resulting oxidative stress contributes to the pathogenesis of glaucomatous optic neuropathy.

What is the present pathogenetic concept of glaucomatous optic neuropathy?

Glaucomatous optic neuropathy implies loss of neural tissue, activation of glial cells, tissue remodeling, and change of blood flow. The blood flow reduction is not only secondary but has a primary component. Activation of astrocytes leads to an altered microenvironment. An unstable ocular perfusion, either due to IOP fluctuation or a disturbed autoregulation (due to primary vascular dysregulation syndrome) leads to a mild reperfusion injury. The superoxide (O(2)(-)) anion produced in the mitochondria of the axons, fuses with the nitric oxide (NO) diffusing from the astrocytes, leading to the damaging peroxynitrite (ONOO(-)). It is possible that the diffusion of endothelin and metalloproteinases to the surrounding of the optic nerve head leads to a local vasoconstriction and thereby increases the risk for venous occlusion and weakens the blood-brain barrier, which in extreme situations results in splinter hemorrhages. Activated retinal astrocytes can be visualized clinically. The involvement of primary vascular dysregulation in the pathogenesis of glaucomatous optic neuropathy may explain why women, as well as Japanese, suffer more often from normal-tension glaucoma.

Is there more to glaucoma treatment than lowering IOP?

Classic glaucoma treatment focuses on intraocular pressure (IOP) reduction. Better knowledge of the pathogenesis of the disease has opened up new therapeutical approaches. Whereas most of these new avenues of treatment are still in the experimental phase, others, such as magnesium, gingko, salt and fludrocortisone, are already used by some physicians. Blood pressure dips can be avoided by intake of salt or fludrocortisone. Vascular regulation can be improved locally by carbonic anhydrase inhibitors, and systemically with magnesium or with low doses of calcium channel blockers. Experimentally, glaucomatous optic neuropathy can be prevented by inhibition of astrocyte activation, either by blockage of epidermal growth factor receptor or by counteracting endothelin. Glaucomatous optic neuropathy can also be prevented by nitric oxide-2 synthase inhibition. Inhibition of matrix metalloproteinase-9 inhibits apoptosis of retinal ganglion cells and tissue remodeling. Upregulation of heat shock proteins protects the retinal ganglion cells and the optic nerve head. Reduction of oxidative stress especially at the level of mitochondria also seems to be protective. This can be achieved by gingko; dark chocolate; polyphenolic flavonoids occurring in tea, coffee, or red wine; anthocyanosides found in bilberries; as well as by ubiquinone and melatonin.

What is the link between vascular dysregulation and glaucoma?

The need of blood flow to different organs varies rapidly over time which is why there is sophisticated local regulation of blood flow. The term dysregulation simply means that blood flow is not properly adapted to this need. Dysregulative mechanisms can lead to an over- or underperfusion. A steady overperfusion may be less critical for long-term damage. A constant underperfusion, however, can lead to some tissue atrophy or in extreme situations to infarction. Unstable perfusion (underperfusion followed by reperfusion) leads to oxidative stress. There are a number of causes that lead to local or systemic vascular dysregulation. Systemic dysregulation can be primary or secondary of nature. A secondary dysregulation is due to other autoimmune diseases such as rheumatoid arthritis, giant cell arteritis, systemic lupus erythematodes, multiple sclerosis, colitis ulcerosa, or Crohns disease. Patients with a secondary vascular dysregulation normally have a high level of circulating endothelin-1 (ET-1). This increased level of ET-1 leads to a reduction of blood flow both in the choroid and the optic nerve head but has little influence on autoregulation. In contrast, primary vascular dysregulation has little influence on baseline ocular blood flow but interferes with autoregulation. This, in turn, leads to unstable oxygen supply, which seems to be a relevant component in the pathogenesis of glaucomatous optic neuropathy.

A novel perspective on natural therapeutic approaches in glaucoma therapy.

Glaucoma is becoming recognised as a condition for which not only elevated intraocular pressure (IOP), but also non-pressure-dependent risk factors, are responsible. Better knowledge of the pathogenesis has opened up new therapeutic approaches that are often referred to as non-IOP-lowering treatment. These new avenues of treatment, some of which are still under investigation, include agents that can improve vascular regulation and blood flow to the eye and reduce oxidative stress. Vascular regulation can be improved systemically with magnesium. Dark chocolate and omega-3-fatty acids can also improve blood flow regulation. Oxidative stress at mitochondrial level can be reduced by gingko. Polyphenolic flavonoids (tea, coffee and red wine), anthocyanosides, ubiquinone and melatonin have antioxidant properties, and heat-shock proteins can be induced naturally by the use of sauna baths. Future intensive studies on the effect of these compounds may open up a new therapeutic era in glaucoma.

Mental health measures of anxiety and depression in patients with retinal detachment.

In this study, the researchers examined anxious and depressive symptoms of patients with rhegmatogenous retinal detachment (RRD) prior to and up to year after retinal detachment surgery. One hundred and thirteen (113) patients with RRD took part in this prospective longitudinal study. Anxiety and depression were evaluated using the Hospital Anxiety and Depression Scale (HADS). Visual acuity (VA) results and HADS scores of all participants were recorded prior to and 3, 6 and 12 months after retinal detachment surgery. Pearson correlation analysis showed a significant association between the patients' VA and HADS psychological scores both prior to and three months after surgery, regardless of the type of surgery performed. Psychological distress is a significant problem associated with retinal detachments that requires more attention.

Retinal venous pressure measurements in patients with Flammer syndrome and metabolic syndrome.

BACKGROUND: The purpose of this research is to analyze retinal venous pressure (RVP) of both eyes of patients who visited a Swiss ophthalmic practice and compare values among the following groups of patients with primary open-angle glaucoma (POAG), Flammer syndrome (FS), and metabolic syndrome (MetS). METHODS: RVP was measured in both eyes of all patients who visited a Swiss ophthalmic practice during March 2016 till November 2016, and the results were analyzed retrospectively. All measurements were performed by one physician by means of ophthalmodynamometry. Ophthalmodynamometry is done by applying an increasing pressure on the eye via a contact lens. The minimum force required to induce a venous pulsation is called ophthalmodynamometric force (ODF). The RVP is defined and calculated as the sum of ODF and intraocular pressure (IOP) [RVP = ODF + IOP]. RESULTS: Spontaneous central retinal venous pulsation was present in the majority of the patients (192 out of 357, 53.8%). Spontaneous RVP rate was significantly negatively correlated with age (r = -0.348, p < 0.001). A significantly increased RVP was noted in FS, MetS, and POAG patients, particularly those POAG patients who also suffered from FS (p < 0.005). CONCLUSIONS: Although most patients had a spontaneous RVP, those with FS, POAG, and MetS had increased RVP. Measuring RVP by means of ophthalmodynamometry provides predictive information about certain ocular diseases and aids in instituting adequate preventive measures.

Nutritional recommendations for individuals with Flammer syndrome.

The Flammer syndrome (FS) describes the phenotype of people with a predisposition for an altered reaction of the blood vessels to stimuli like coldness or emotional stress. The question whether such people should be treated is often discussed. On the one hand, most of these subjects are healthy; on the other hand, FS seems to predispose to certain eye diseases such as normal tension glaucoma or retinitis pigmentosa or systemic diseases such as multiple sclerosis or tinnitus. A compromise between doing nothing and a drug treatment is the adaption of nutrition. But what do we mean by healthy food consumption for subjects with FS? The adaption of nutrition depends on the health condition. Whereas patients with e.g. a metabolic syndrome should reduce their calorie intake, this can be counterproductive for subjects with FS, as most subjects with FS have already a low body mass index (BMI) and the lower the BMI the stronger the FS symptoms. Accordingly, while fasting is healthy e.g. for subjects with metabolic syndrome, fasting can even dangerously aggravate the vascular dysregulation, as it has been nicely demonstrated by the loss of retinal vascular regulation during fasting. To give another example, while reducing salt intake is recommended for subjects with systemic hypertensions, such a salt restriction can aggravate systemic hypotension and thereby indirectly also the vascular regulation in subjects with FS. This clearly demonstrates that such a preventive adaption of nutrition needs to be personalized.

Comet assay as an indirect measure of systemic oxidative stress.

Higher eukaryotic organisms cannot live without oxygen; yet, paradoxically, oxygen can be harmful to them. The oxygen molecule is chemically relatively inert because it has two unpaired electrons located in different pi * anti-bonding orbitals. These two electrons have parallel spins, meaning they rotate in the same direction about their own axes. This is why the oxygen molecule is not very reactive. Activation of oxygen may occur by two different mechanisms; either through reduction via one electron at a time (monovalent reduction), or through the absorption of sufficient energy to reverse the spin of one of the unpaired electrons. This results in the production of reactive oxidative species (ROS). There are a number of ways in which the human body eliminates ROS in its physiological state. If ROS production exceeds the repair capacity, oxidative stress results and damages different molecules. There are many different methods by which oxidative stress can be measured. This manuscript focuses on one of the methods named cell gel electrophoresis, also known as "comet assay" which allows measurement of DNA breaks. If all factors known to cause DNA damage, other than oxidative stress are kept constant, the amount of DNA damage measured by comet assay is a good parameter of oxidative stress. The principle is simple and relies upon the fact that DNA molecules are negatively charged. An intact DNA molecule has such a large size that it does not migrate during electrophoresis. DNA breaks, however, if present result in smaller fragments which move in the electrical field towards the anode. Smaller fragments migrate faster. As the fragments have different sizes the final result of the electrophoresis is not a distinct line but rather a continuum with the shape of a comet. The system allows a quantification of the resulting "comet" and thus of the DNA breaks in the cell.

Retinal venous pressure in chronic smokers.

BACKGROUND: The overall aim of this study was to determine retinal venous pressure (RVP) in healthy chronic smokers and compare values to those of healthy non-smokers. METHODS: Both eyes of 25 healthy chronic smokers and 41 healthy non-smokers were included. Measurements of RVP were performed by means of contact lens ophthalmodynamometry. Ophthalmodynamometry is done by applying increasing force on the eye via a contact lens. If a spontaneous venous pulsation was present, it was noted. If not, the compressive force was increased until the first venous pulsation was detected, and the measurement value was fixed and read. RVP was calculated as the sum of pressure increase induced by the instrument and intraocular pressure. RESULTS: Smokers had a significantly higher frequency of spontaneous venous pulsations than non-smokers (p < 0.001). Mean values of RVP were slightly lower in smokers than in non-smokers: 15.3 and 15.5 (smokers) versus 15.9 and 16.2 (non-smokers) for the right and left eye, respectively; however, the difference in RVP between the two groups did not reach significance. There was no significant difference in blood pressure between the two groups, but heart rate was significantly higher in smokers (p = 0.043). CONCLUSIONS: RVP values may differ in healthy smokers than in non-smokers. Therefore, smoking habits should be considered when interpreting RVP results.

The role of the carotenoids, lutein and zeaxanthin, in protecting against age-related macular degeneration: a review based on controversial evidence.

PURPOSE: A review of the role of the carotenoids, lutein and zeaxanthin, and their function in altering the pathogenesis of age-related macular degeneration (AMD). METHODS: Medline and Embase search. RESULTS: Recent evidence introduces the possibility that lutein and zeaxanthin, carotenoids found in a variety of fruits and vegetables may protect against the common eye disease of macular degeneration. This potential and the lack to slow the progression of macular degeneration, has fueled high public interest in the health benefits of these carotenoids and prompted their inclusion in various supplements. The body of evidence supporting a role in this disease ranges from basic studies in experimental animals to various other clinical and epidemiological studies. Whilst some epidemiological studies suggest a beneficial role for carotenoids in the prevention of AMD, others are found to be unrelated to it. Results of some clinical studies indicate that the risk for AMD is reduced when levels of the carotenoids are elevated in the serum or diet, but this correlation is not observed in other studies. Published data concerning the toxicity of the carotenoids or the optimum dosage of these supplements is lacking. CONCLUSION: An intake of dietary supplied nutrients rich in the carotenoids, lutein and zeaxanthin, appears to be beneficial in protecting retinal tissues, but this is not proven. Until scientifically sound knowledge is available we recommend for patients judged to be at risk for AMD to: alter their diet to more dark green leafy vegetables, wear UV protective lenses and a hat when outdoors. Future investigations on the role of nutrition, light exposure, genetics, and combinations of photodynamic therapy with intravitreal steroid (triamcinolone-acetonide) injections hold potential for future treatment possibilities.