[Bilateral papilledema. Pseudotumor cerebri].
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Biomedical subjects
Publications and source records attributed to A Remky.
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PURPOSE: To compare the effects of latanoprost and timolol-XE on ocular pressure and perfusion in healthy adults, with respect to episcleral venous pressure. METHODS: A double-masked, placebo-controlled crossover study of weeklong bedtime treatment with one drop of drug, with placebo contralaterally, followed by a 3-week washout and alternate-drug/contralateral-placebo repeat. Intraocular pressure was measured by applanation and by pneumotonometry, providing pulsatile ocular circulatory estimates. Measurements of episcleral venous pressure were obtained (Friberg method). RESULTS: Twenty subjects participated (five men, 15 women; mean age, 39 years (range, 21 to 55 years); mean baseline intraocular pressure, 13.4 mm Hg). A greater decrease in intraocular pressure was seen among these subjects the morning after initiating treatment with latanoprost (-2.0 mm Hg; P <.0001) than with timolol-XE (-0.9 mm Hg; P =.051) (latanoprost versus timolol DeltaP =.008). This ocular hypotensive effect remained significant that evening with latanoprost (-3.2 mm Hg; P <.0001) but not with timolol XE (-1.0 mm Hg; P =.2). By the morning of day 8, mean intraocular pressure remained 3.2 mm Hg below baseline with latanoprost and 2.3 mm Hg below baseline with timolol-XE (P <.0001 for both drugs). Neither drug altered episcleral venous pressure. Among a subgroup of nine subjects with comparable intraocular pressure reductions with the two drugs, latanoprost treatment was associated with a 16.7% increase in mean pulsatile ocular blood flow (P =.04) through the weeklong treatment interval, consistently higher than during timolol-XE treatment of the same subjects. CONCLUSION: Latanoprost caused an overnight decrease in intraocular pressure in normotensive normal eyes, and both drugs significantly reduced intraocular pressure within 1 week. Intraocular pressure remained higher than episcleral venous pressure throughout treatment with both drugs. Latanoprost was associated with enhanced pulsatile ocular perfusion not seen with timolol-XE treatment.
OBJECTIVE: To perform three-dimensional, noninvasive, quantitative analysis of cystoid macular edema and macular cysts using infrared scanning laser tomography and to correlate findings with visual acuity (VA) as a basis for interventional studies. DESIGN: Cross-sectional, nonrandomized study. PARTICIPANTS: Seventeen patients (29-86 years of age) with macular cysts associated with a broad spectrum of diseases. INTERVENTION: Confocal infrared imaging with scanning laser tomography with the TopSS (790 nm) (Laser Diagnostic Technologies, San Diego, CA) with digitized images was used to perform three-dimensional, quantitative analysis of cysts in the central 5 degrees of the macula. MAIN OUTCOME MEASURES: Measurements of macular cyst number, area, volume, depth, slope, height of the surrounding macular elevation, and correlation with VA. RESULTS: Scanning laser tomography detected macular cysts in all patients. The number per patient ranged from 1 through 15. Cysts were accompanied by surrounding macular elevation in 16 patients (mean macular height, 216 microm). The area covered by cysts in the central 5 degrees was 0.087 to 0.969 mm2, and volume was 0.007 to 0.549 mm3. Visual acuity was significantly poorer in patients with greater cyst area (P = 0.0007), cyst volume (P = 0.0009), macular thickening (P = 0.0002), and cyst depth (P = 0.0013). Cyst number, average slope, and maximum slope, however, did not correlate significantly with VA. Grouping of macular cysts according to macular height and average cyst depth revealed that cysts in a more thickened retina were significantly deeper, had steeper slopes, and corresponded to worse VA. Macular height and average cyst depth were highly associated with each other, suggesting that in eyes with surrounding macular edema, cysts were deeper and may reflect more widespread tissue destruction. Individual confocal tomographic images provided additional information. Neither ophthalmoscopy nor fluorescein angiography delineated features such as retinal folds that suggested vitreous traction or changes in deeper layers that suggested occult choroidal new vessels. CONCLUSIONS: Infrared scanning laser tomography is a rapid and noninvasive imaging method that provides quantitative analysis of macular cysts in addition to qualitative information not seen clinically. Because poor VA is related to severe involvement of the central retina, scanning laser tomography could provide an objective outcome measure for interventional studies.
BACKGROUND: The "Swedish Interactive Threshold Algorithm" (SITA) is a new technique minimizing test time without reduction of data quality. In this retrospective study we compared visual fields assessed with the conventional full-threshold technique with those by SITA and analyzed qualitative and quantitative differences and the test time reduction of SITA. PATIENTS AND METHODS: 113 eyes with different glaucomatous field damage of 66 patients aged from 22 to 89 years were included. The patients underwent perimetry with each strategy within four months. Exclusion criteria were eyes with progressing glaucomatous damage and high rate of false-positive results or artifacts by corrective glasses. RESULTS: The qualitative differences of the analysis were small: full threshold demonstrated more relative scotomas in eyes with normal SITA readings, whereas scotomas assessed with SITA were often pronounced to absolute scotomas. Average time reduction by SITA was 40% and depended on the severity of glaucomatous stage. No reduction was found for advanced glaucoma, whereas normal fields using SITA were performed in half of the time of full threshold strategy. CONCLUSION: Differences of SITA to conventional full threshold testing may be related to fatigue effects of full threshold strategy due to longer test time. The reduction of test time enables more motivation for more frequent visual field examinations and thus a better detection of early glaucoma or progressing visual field damage.
BACKGROUND: Previous fluorescein angiographic studies have shown alterations in the macular microcirculation in patients with diabetes mellitus and arterial hypertension. In both diseases capillary blood velocity was reduced and capillary density decreased. These changes were more pronounced in diabetic patients. We have examined the influence of arterial hypertension in combination with diabetes mellitus. METHODS: 62 patients with diabetes mellitus and arterial hypertension (group 1) were matched with patients with diabetes mellitus but without arterial hypertension (group 2, match criteria: ETDRS stage of retinopathy). In all subjects fluorescein angiograms were performed with a scanning laser ophthalmoscope. Macular capillary blood velocity (CBV), perifoveal intercapillary area (PIA), the coefficient of variation of both parameters, the area of the foveal avascular zone (FAZ), and the arteriovenous passage time (AVP) were assessed by digital image analysis. RESULTS: Systolic and diastolic blood pressures were significantly increased in the patients with arterial hypertension (systolic p=0.0008; diastolic p=0.03). Neither dynamic measures (AVP: 1.64 (0.49) seconds (group 1), 1.72 (0.58) seconds (group 2); CBV: 1.98 (0.39) mm/s (group 1), 2.09 (0.43) mm/s (group 2)) nor morphological measures (PIA: 7985 (3137) microm(2) (group 1), 8338 (3376) microm(2) (group 2); FAZ: 0.319 (0.206) mm(2) (group 1), 0.363 (0.237) mm(2) (group 2)) were significantly different between the two groups of diabetic patients. CONCLUSION: Arterial hypertension did not result in more severe macular capillary dropout than diabetes without hypertension. This might be explained by the fact that most of the patients were being treated with antihypertensive drugs.
AIM: To compare the effect of altitudinal asymmetric glaucomatous damage on retinal microcirculation in patients with normal pressure glaucoma (NPG). METHODS: In a prospective cross sectional study patients with NPG (washed out for antiglaucomatous therapy) and altitudinal asymmetric perimetric findings between the superior and inferior hemisphere (Humphrey 24-2) (n=18) were included and compared with 20 NPG patients with symmetrical field defects and 18 healthy subjects. Fluorescein angiograms were performed using a scanning laser ophthalmoscope. Using digital image analysis, arteriovenous passage time (AVP) and vessel diameters were assessed for comparison of corresponding affected and less affected temporal arcades. RESULTS: Both affected and less affected hemispheres showed significantly prolonged AVP times (p<0.001) when compared with healthy subject data. In hemispheres with more severe glaucomatous field loss the AVP times were significantly (p=0.04) prolonged compared with the less affected hemisphere (AVP affected 3.1 (SD 7) seconds v AVP less affected 2.61 (1.4) seconds). There was no asymmetry effect on arterial and venous diameter measurements. CONCLUSION: Altitudinal visual field defects are linked together with circulatory deficits of the retinal tissue. The attenuated circulation seems to be a considerable factor in the natural course of glaucomatous optic neuropathy.
The presence of isolated cotton-wool spots in normal fundi may indicate serious systemic disease. In this presentation 4 patients were examined for blurred vision or scotomas with sudden onset. Two of them were pregnant. Funduscopic examination revealed soft-appearing white spots in the temporal arcades in 3 patients and in the papillomacular bundle in 1 patient. Due to the lack of other fundus lesions 3 of the patients were initially treated for toxoplasmosis. The patients were seronegative for typical viral (HIV), antinuclear antibodies, bacterial infections, or toxoplasmosis. Blood pressures, glycosylated hemoglobin and blood counts were in the normal range. At the follow-up examinations subjective symptoms had improved and the spots disappeared or were smaller and showed more distinct borders, and no new lesions were detected. These cases suggest that isolated cotton-wool spots may occur without serious systemic disease in otherwise healthy subjects and the spots may be misinterpreted as acute inflammatory retinochoroidal lesions.
PURPOSE: To correlate short-wavelength cone-mediated sensitivity (SWS) assessed by blue-on-yellow perimetry with alterations of the perifoveal vascular bed in early diabetic maculopathy. METHODS: Thirty-one patients (21 M, 10 F; mean age, 35 +/- 12 years; no lens opacities) with no clinically significant macular edema were included in this study. All patients underwent short-wavelength automated perimetry (SWAP) and conventional white-on-white perimetry (Humphrey, 10-2). In digitized video fluorescein angiograms (Scanning Laser Ophthalmoscope), the size of the foveal avascular zone (FAZ) and the mean perifoveal intercapillary area (PIA) as a measure of capillary density were quantified interactively. RESULTS: Mean thresholds of SWAP were significantly correlated with increasing size of FAZ (r = -0.51, P = 0.003) and PIA (r = -0.47, P = 0.01), whereas visual acuity expressed by log MAR (FAZ: r = 0.15, P = 0.41; PIA: r = 0.06, P = 0.76) and mean thresholds assessed with white-on-white perimetry (FAZ: r = -0.25, P = 0.20; PIA: r = -0.31, P = 0.14) were unrelated to diabetic changes of the perifoveal capillary network. CONCLUSIONS: The alterations of the perifoveal network are related to selective disturbances of visual function as measured by blue-on-yellow-perimetry. SWAP may act as an early detector of visual function loss in early diabetic maculopathy and serve as a helpful technique to predict early ischemic damage of the macula and to monitor therapy.
UNLABELLED: Chronic ischemia of the retina and the optic nerve head seems of importance especially in patients with normal-tension glaucoma (NTG). The purpose of this study was to examine the retinal hemodynamics in patients with NTG. PATIENTS: Twenty-five patients with NTG were examined (3 weeks washout period) in this study (age 58 +/- 16 years). The arteriovenous passage (AVP) time and arterial and venous diameters from scanning laser fluorescein angiograms were evaluated by means of digital image analysis. RESULTS: The AVP time in patients with NTG (2.78 +/- 1.1 s) was significantly prolonged (P < 0.0001) compared with healthy subjects (1.58 +/- 0.4 s). No significant correlation was found between arterial and venous diameters, intraocular pressure, blood pressure or calculated perfusion pressure and retinal arteriovenous passage time. CONCLUSION: Patients with NTG showed prolonged retinal passage, which could cause chronic hypoxia. This prolongation of circulation is not correlated with any of the clinical parameters. Thus, a circulatory defect might be a primary factor in the pathogenesis of NTG.
BACKGROUND: Cystoid macular edema (CME), a cause of central visual loss, is described in various pathologies. Typically, the fluorescein angiogram confirms the diagnosis and provides qualitative information as to the extent of leakage. This study was performed to investigate the features of cysts and quantify the extent of CME using non-invasive infrared imaging. METHODS: Eighteen eyes of 16 successive patients with CME in association with a broad spectrum of diseases were included in the study. The diagnosis of CME was established clinically and confirmed by fluorescein angiography. Digital infrared imaging was performed with a research scanning laser ophthalmoscope with different apertures, providing direct confocal and indirect imaging modes, to discriminate superficial features from deeper ones and to emphasize sources of multiple laterally scattered light. RESULTS: CME was easily detected with infrared imaging in all eyes. Confocal mode visualized the cysts themselves, while indirect mode emphasized borders. Large central cysts were detected as distinct, non-confluent structures. In addition, folds detected with infrared imaging in the macula in 12 of the 18 eyes were not always observed clinically. CONCLUSION: Infrared imaging provides a quick and safe diagnostic tool for patients with CME. The cystoid structures are readily localized and quantified, useful for monitoring CME. Despite differences in the pathophysiology, cysts did not differ qualitatively in a variety of diseases with infrared imaging.
PURPOSE: Scanning laser ophthalmoscopy is capable of producing high-resolution fluorescein angiograms. Measurements of capillary blood velocities in the fovea are well established. In this study, we used an identical technique to measure particle velocities in the superficial layers of the optic nerve head. We compared these data with simultaneous velocity measurements in the retinal and macular vasculature. METHODS: Fluorescein angiograms were performed in 30 subjects (12 men, 18 women; mean age, 26 years; standard deviation [SD], 3 years). Off-line, the velocities of hypofluorescent particles through the microvasculature of epipapillary and macular vessels were measured by image-processing techniques. We also assessed the arteriovenous passage (AVP) time of the fluorescein dye front. RESULTS: Epipapillary blood velocities ranged from 2.7 to 6.5 mm/sec (mean, 4.0 mm/sec; SD, 0.99 mm/sec) and differed significantly from macular capillary blood velocities (MCBVs), which ranged from 1.67 to 3.31 mm/sec (mean, 2.53 mm/sec; SD, 0.34 mm/sec). The AVP time in all subjects was 1.74 +/- 0.5 sec (mean +/- SD) and correlated with the MCBV (P < 0.05, r = -0.46). Epipapillary blood velocities showed no correlation with either AVP time or MCBV. CONCLUSIONS: The scanning laser methodology, adapted to objectively assess velocities in the epipapillary vasculature, shows that these measurements are neither correlated with velocities in the perifoveal network, nor inversely correlated with overall retinal transit time. Epipapillary blood velocities were found to be substantially higher than those measured in macular capillaries. This result might be explained by the different anatomy of epipapillary vessels compared with macular capillaries.
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PURPOSE: Topical beta-blockers are the most common treatment for ocular hypertension in glaucoma, but their ocular hemodynamic effects are not well known. We investigated the acute effects of betaxolol (beta-1 selective antagonist), levobunolol (non-selective antagonist with active polar metabolite), and timolol (non-selective antagonist) on retinal and superficial optic nerve head circulation. METHODS: Intraocular pressure (IOP), heart rate, blood pressure, and retinal circulation were evaluated in 12 healthy subjects (6F/6M; mean age=24+/-2 years) before and two hours after instillation of each drug on separate occasions at least two weeks apart. Macular capillary blood velocity (MCBV), epipapillary blood velocities (EBV), arteriovenous passage (AVP) times, and arterial and venous diameters were measured by digital image analysis of scanning laser fluorescein angiograms. RESULTS: All drugs significantly (p<0.05) reduced IOP. There was no significant effect on blood pressure or calculated ocular perfusion pressure. Only levobunolol significantly lowered heart rate (p<0.05). Each drug produced a significant (p<0.01) decrease in AVP time of approximately 25%. MCBV was significantly (p<0.01) increased by approximately 20% in all three conditions; each drug also produced significant (p<0.01) increases in EBV. Arterial and venous diameters remained unaffected. CONCLUSION: All three drugs, despite different beta-adrenergic properties, increased blood velocities in retinal and epipapillary capillaries. These changes, occurring as they do in concert with decreased retinal arteriovenous passage time at constant retinal arterial and venous diameter, may indicate improved retinal perfusion after drug treatment. Improved circulation, if it indeed occurs, in tandem with reduced IOP, might explain in part the beneficial effect of beta-adrenoreceptor blocking agents in glaucomatous patients.
BACKGROUND: Infrared (IR) imaging improved by using scanning laser ophthalmoscopy. The greater penetration of infrared light compared with visible wavelengths permits better visualization of subretinal structures such as drusen, hyperpigmentations and choroidal new vessels. Furthermore, using the indirect mode of the instrument to detect laterally scattered light, drusen and shallow detachments of the neuroretina can easily be visualized as prominent structures. In this study we investigated the potential use of non-invasive infrared imaging in follow-up examination of patients with central serous chorioretinopathy (CSCR). METHODS: All patients with an acute CSCR underwent fluorescein angiographic studies (488 nm) and infrared imaging (788 nm) in indirect mode using a scanning laser ophthalmoscope (SLO 101; Rodenstock) at baseline and follow-up after 3-5 weeks. RESULTS: The detachment of the neuroretina could easily be visualized by infrared imaging as prominent, oval-shaped structures. The height varied corresponding to the clinical course, whereas the extent showed no relation to the change in symptoms. CONCLUSION: IR-imaging is a quick, non-invasive tool which may efficiently be used in chorioretinal diseases. In CSCR patients it provides an adjunct in clinical follow-up by monitoring the course of the disease and the effect of treatment concepts.
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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.
PURPOSE: Severe eye burns often result in extensive necrosis of the conjunctiva and episcleral tissue. Video fluorescein angiography was performed to reveal the perfusion of the anterior eye segment after severe eye burns. METHODS: A scanning laser ophthalmoscope was used for anterior segment fluorescein angiography in 12 patients (14 eyes) with severe burns grade III-IV and in 7 healthy volunteers. RESULTS: Necrotic tissues occurred as non perfused areas and remained dark throughout the whole angiogram. In general, the borders from healthy to necrotic conjunctival tissue were sharply demarcated. Thus, the extent of scleral and limbal ischemia could be determined exactly. Injured vessels showed hyperfluorescence with late leakage. Damage of the subconjunctival tissue appeared as a deep weak fluorescence in the early angiography and exhibited patchy leakage in the late angiogram. CONCLUSIONS: Anterior segment angiography provides a basis for deciding the extent of surgical debridement of necrotic tissue in the acute phase of the burn. The determination of the extent of limbal and scleral ischemia may give useful information for early plastic-reconstructive procedures.
Purtscher's retinopathy is a rare complication after trauma to the chest or bone fractures. We report about a patient, which we examined 6 months after a serious car accident. Visual acuity was 20/20 in both eyes. Examination with the Amsler grid revealed a paracentral scotoma in the left eye. In the fluorescein angiography of the left eye performed with a scanning laser ophthalmoscope we found capillary dropout, which corresponded well to the scotoma. Measured by digital image analysis, the area of the foveal avascular zone was eccentrically enlarged by a factor of 4. The mean perifoveal intercapillary area was also enlarged in the corresponding quadrant. This reflects that focal capillary dropout may result in scotoma rather than in a decrease in visual acuity as reported in other diseases.