Indocyanine green guided laser photocoagulation in patients with occult choroidal neovascularisation.

AIMS: To determine whether indocyanine green (ICG) guided laser photocoagulation of occult choroidal neovascularisations (OCNV) is beneficial for patients with occult choroidal neovascularisation secondary to age related macular degeneration (AMD). METHODS: A prospective pilot study was performed in 21 eyes with OCNV secondary to AMD that could be identified extrafoveolarly or juxtafoveolarly in an early ICG angiographic study. Laser photocoagulation was applied to the neovascular membrane identified in the early ICG angiographic study. RESULTS: Visual acuity ranged from 20/400 to 20/20 (logMAR 0.54 (SD 0.29) before and hand movements and 20/30 (logMAR 0.81 (0.69)) at the last follow up after laser photocoagulation. During the follow up (30 (13) months) vision improved in four eyes (two lines), in seven eyes the initial visual acuity could be stabilised (two lines), in five eyes vision dropped moderately (three to five lines), and in five eyes vision decreased severely (six or more lines). Recurrences (seven patients) or persistent CNV (six patients) was observed in 13 patients. CONCLUSION: This preliminary study of ICG guided laser photocoagulation of occult extrafoveal and juxtafoveal choroidal neovascularisations suggests that this technique may improve the visual prognosis of these patients. Further prospective controlled studies are necessary to confirm these data.

[Risk factors in patients with amaurosis fugax]. / Risikofaktoren bei Patienten mit Amaurosis fugax.

BACKGROUND: In the diagnosis of retinal and cerebral vascular occlusion and migraine amaurosis fugax may be an important symptom. To evaluate the relation between cardiovascular diseases and amaurosis fugax we investigated the risk factors in patients with amaurosis fugax. MATERIALS AND METHODS: Twenty-four patients (14 m, 10 f; aged 22 to 84 years; mean: 55 +/- 19 years) with amaurosis fugax were included in this study. All patients underwent a detailed clinical and ophthalmological examination, including video fluorescein angiography shortly after the event. RESULTS: The duration of symptoms ranged from 30 seconds to 30 minutes (median: 3 minutes). Additional acute symptoms were headache in eight patients and tinnitus in one patient. Visual acuity showed no difference between the effected and the fellow eye. Intraocular pressure was normal in all eyes. Video fluorescein angiography revealed normal retinal perfusion times in all cases (arm-retina-time: 12.9 +/- 3.8 s; arteriovenous passage time: 1.8 +/- 0.7 s). Cardiovascular risk factors were present in all patients: 58% of the patients suffered from arterial hypertension, 8% of the patients from diabetes mellitus. Hyperlipidaemia was diagnosed in 17% of the patients, 46% of the patients were smokers. A history of cardiovascular disease (e.g. myocardial infarction, vitium, arrhythmia) was found in 58% of the patients. Cerebrovascular disease was diagnosed in 54% of the patients (migraine: 33%). CONCLUSIONS: The ophthalmologic examination especially the fluorescein angiography revealed no pathologic findings in patients with amaurosis fugax. The risk factor distribution corresponded to data found in patients with retinal artery occlusion.

Imaging of retinal autofluorescence in patients with age-related macular degeneration.

BACKGROUND: Several studies have demonstrated an accumulation of autofluorescent materials in the retinal pigment epithelium (RPE) with increasing age. Histologic analysis revealed that lipofuscin is the most potential fluorescent substance in the aging RPE. Therefore, it has been speculated that lipofuscin precedes the presence of drusen and the development of age-related macular degeneration (ARMD). METHOD: A scanning laser ophthalmoscope was used to visualize autofluorescence in the fundus of patients with early ARMD. The digital recordings were analyzed offline with a digital image analyzing system. RESULTS: In 85 of 103 patients, focal areas of increased autofluorescence were visible. Areas of hyperpigmentation at the level of the RPE showed increased autofluorescence in all cases, whereas areas of depigmentation demonstrated decreased autofluorescence. CONCLUSION: Patients with ARMD demonstrated focal accumulation of fluorescent material most likely lipofuscin. Thus, the scanning laser technique combined with an image analyzing system may help to identify eyes at risk for developing exudative ARMD.

[Retinal hemodynamics in patients with hyperviscosity syndrome]. / Retinale Hämodynamik bei Patienten mit Hyperviskositätssyndrom.

BACKGROUND: The hyperviscosity syndrome (e.g. plasmacytoma, cryoglobulinaemia and Waldenström's macroglobulinaemia) leads through the polymerisation of macro-molecules to an increased blood viscosity. This may result in microcirculatory disturbances in various organs. In the retina the hyperviscosity produces a pattern of retinal changes including dot and blot hemorrhages, retinal and optic nerve head edema and increased diameters of the veins. In the present study we quantified the retinal hemodynamic in patients with hyperviscosity syndrome. PATIENTS AND METHODS: Fifteen patients aged between 35 and 72 years were included in the study. Ten presented with Waldenström's macroglobulinaemia, two with cryoglobulinaemia and three with plasmacytoma. All patients underwent video fluorescein angiographic studies. The arteriovenous passage time (AVP) representing the retinal microcirculation and the arm retina time (ART) were quantified from the angiograms. In addition, hematocrit (Hct) and the plasma viscosity (ETA) were measured. RESULTS: The AVP was significantly prolonged in patients with hyperviscosity syndrome in comparison to healthy volunteers (AVP: 2.6 +/- 1.5 s vs. 1.6 +/- 0.4 s; p < 0.05). The ART showed no significant differences. Plasma viscosity was doubled in the patients as compared with reference values (ETA: 2.54 +/- 2.23 mPas vs. 1.24 +/- 0.08 mPas; p < 0.01). CONCLUSIONS: The simultaneous rising of plasmaviscosity and arteriovenous passage time suggests that the increase of plasmaviscosity causes retinal circulatory disturbance. All this may result in the typical fundus changes in patients with hyperviscosity syndrome.

[Quantification of cystoid changes in diabetic macular edema]. / Quantifizierung von zystoiden Veränderungen bei diabetischem Makulaödem.

BACKGROUND: Cystoid changes in diabetic macular oedema can result in severe visual consequences and were previously difficult to quantify. This study was performed to introduce reliable measurements of the area covered by cysts, of their quantification and relation to visual acuity. PATIENTS AND METHODS: 58 diabetic patients suffering from cystoid macular oedema were examined by means of a scanning laser ophthalmoscope. Fluorescein angiography provides a detailed recognition of well demarcated cystoid formations in the early transit. In three different sampling areas from the center of the fovea (1.2 deg, 2.5 deg and 5 deg) and in the foveal avascular zone (FAZ) itself the area covered by cystoid changes was quantified as well as the number of cysts and their shortest distance from the center of the FAZ. RESULTS: The mean area covered by cystoid formations in the 2.5 degrees area was 0.128 +/- 0.08 micron2, the number of cysts ranged from 1 to 7. In all sampling areas there was a significant correlation between area of cysts and visual acuity. Their number and distance from the center of the FAZ did not show a significant correlation to vision. Measurements within the 2.5 degrees area seem to have the highest predictability concerning visual function. CONCLUSION: Fluorescein angiography allows the quantification of number and area covered by cystoid formations in patients with diabetic macular oedema. There is a significant correlation of visual acuity to the area covered by these cystoid changes. The distance of cysts from the center of the FAZ does not correlate significantly to visual acuity. These measurements can prove useful in following cystoid changes and in monitoring the effect of currently used therapy regimen.

Perifoveal capillary network in patients with acute central retinal vein occlusion.

PURPOSE: Reduction of visual acuity in patients with central retinal vein occlusion (CRVO) is often caused by macular edema and ischemia. The major causative factor for macular changes may be a disturbance in the macular microcirculation. The authors studied the perifoveal microcirculation in patients with central retinal vein occlusion to quantify the extent of circulatory deficiency in the macular circulation. METHODS: Twenty-four patients (8 men, 16 women) with recently diagnosed CRVO were included in this study. The following data were quantified: mean capillary blood velocity (CBV), foveal avascular zone (FAZ), and mean perifoveal intercapillary area (PIA). RESULTS: In patients with CRVO, the mean flow velocity was significantly reduced compared with healthy subjects (1.63 +/- 0.220 mm/sec vs. 2.89 +/- 0.41 mm/sec, P < 0.01). The FAZ and the mean PIA characterizing capillary density were significantly enlarged in CRVO (5548 +/- 1151 microm2 vs. 3872 +/- 529 microm2; P < 0.01). CONCLUSIONS: The present study demonstrates that CRVO not only led to a decrease in capillary blood velocities, but also to an enlargement of perifoveal intercapillary areas in early stages of the disease.

[Variability of perifoveal microcirculation in healthy probands]. / Schwankungsbreite der perifovealen Mikrozirkulation bei Gesunden.

BACKGROUND: Fluorescein angiography with a scanning laser ophthalmoscope allows the assessment of retinal hemodynamics. Fundamental for all interpretations of the evaluated data is the knowledge of the physiological variation. In the present study we examined the variability of dynamic and morphologic retinal blood flow indices in healthy subjects over a period of one year. PATIENTS AND METHODS: In sixteen healthy volunteers aged from 23 to 34 years video-fluorescein angiography was repeated nine times in one year. At each term arm-retina-time, arteriovenous passage time, mean arterial dye velocity and capillary flow velocity were assessed. In addition the perifoveal intercapillary areas and the foveal avascular zone were determined at the first and last examination. RESULTS: Statistical analysis of the evaluated data did not show any significant variation of the mean values during the one year follow-up. Reliability indices between 0.61 and 0.87 underline a stable position of each subject to the other participants at the single terms. CONCLUSION: The present study demonstrates that retinal hemodynamics are stable over a one year follow-up in healthy subjects. There are not significant changes to expect in retinal hemodynamics assesses in healthy subjects in one year under constant conditions. The knowledge of the intra- and interindividual variation of retinal blood flow indices allows a correct interpretation of pathophysiologic and pharmacological changes in retinal macro- and microcirculation.

Indocyanine-green angiography in patients with occult choroidal neovascularization.

Several studies have stressed the role of indocyanine-green (ICG) angiography in patients with occult choroidal neovascularization (O-CNV) secondary to age-related maculopathy (ARM). The present study was undertaken to evaluate the percentage of eyes that could be converted from O-CNV without suffering pigment epithelial detachment (PED) in well-defined CNV using ICG angiography with a scanning laser system. A total of 112 patients with ARM and O-CNV without PED were included in this prospective study. All patients underwent ICG angiography with a scanning laser system. The early phase (first 3 min) of the ICG angiogram was analyzed for the presence of a neovascular network, whereas focal or irregular hyperfluorescence was noted in the late phase. The early phase of the ICG angiograms revealed in 62 (55%) eyes a well-defined CNV. In 55 of these eyes, late irregular hyperfluorescent and hypofluorescent zones were observed. Another 27 eyes presented with focal hyperfluorescent areas in the latephase studies without having shown a well-demarcated area of neovascularization in the early phase of the ICG angiogram. This study confirms that ICG angiography is an important adjunctive method to fluorescein angiography. In more than 50% of eyes with O-CNV the ICG angiograms obtained with a scanning laser ophthalmoscope enable the visualization of a neovascular network in the early phase.