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Localized suprachoroidal hematomas. Ophthalmoscopic features, fluorescein angiography, and clinical course.

We describe the ophthalmoscopic characteristics, fluorescein angiographic features, and clinical course of four patients with a localized suprachoroidal hematoma. Each of the four patients developed a darkly pigmented fundus lesion a short time following uncomplicated intraocular surgery. In every case, the lesion appeared ophthalmoscopically similar to a choroidal malignant melanoma. However, fluorescein angiography showed neither choroidal fluorescence blockage nor the double-circulation pattern characteristic of choroidal melanomas. Instead, each lesion exhibited a central fluorescein pattern similar to that of the surrounding uninvolved choroid, relative marginal hypofluorescence, and overlying choroidal folds. Ultrasonography revealed acoustic hollowness of each lesion without choroidal excavation. The lesions disappeared completely within 1 to 2 months, leaving no visible trace. We discuss the differential diagnosis of these lesions and stress the diagnostic value of fluorescein angiography.

Aged↗

Biochemical purification and partial characterization of a murine macrophage surface receptor possessing specificity for small aromatic moieties including fluorescein.

Binding properties and requirements for internalization of hapten-protein antigens, such as fluorescein-polyderivatized bovine serum albumin (FITC-BSA) and poly-D-lysine (FITC-PDL), by murine macrophage was consistent with surface receptor recognition of fluorescyl moieties (Cherukuri et al., Mol. Immunol. 34, 21-32, 1997; Cherukuri et al., Cytometry 31, 110-124, 1998). Ligand binding properties of the putative macrophage receptor pointed toward specificity for various aromatic moieties including phenylalanine, phenyloxazolone and fluorescein (Cherukuri and Voss, Mol. Immunol. 35, 115-125, 1998). Purification of the hapten-recognizing receptor from J774 macrophage cells involved subcellular fractionation of plasma membrane fractions, and affinity chromatography of solubilized membranes employing a phenyl-Sepharose adsorbent with subsequent specific elution of receptor using fluorescein ligand. The final product was a protein with a molecular mass of approximately 180 kDa. Characterization of the purified receptor involved absorption and fluorescence spectroscopy, circular dichroism, fluorescence quenching analyses, various ligand binding assays and an immunological analysis. Spectroscopic analyses revealed that the receptor possessed aromatic amino acids while circular dichroism suggested significant alpha-helical secondary structure. Binding specificity of the purified receptor was confirmed in a spectrofluorometric assay where the fluorescence of fluorescein ligand was quenched approximately 97%. Finally, specific binding activity of the receptor with FITC-BSA was demonstrated in Western blot analysis under native conditions. Receptor purity was confirmed in amino acid sequencing analysis when the amino-terminal residue was found to be totally blocked. Results are discussed in terms of the possible identity of the isolated macrophage receptor and its biological-immunological role.

Animals↗

Cytosine detection by a fluorescein-labeled probe containing base-discriminating fluorescent nucleobase.

We report on a new method for the detection of a base at a specific site in a DNA sequence by monitoring the fluorescence emission of fluorescein. To achieve this goal, we developed a new base-discriminating fluorescent (BDF) nucleobase, naphthodeazaadenine ((ND)A). The fluorescence spectrum of the duplex possessing a cytosine base as a complementary base of (ND)A showed a fluorescence peak at 383 nm when using an excitation wavelength of 350 nm. When the complementary base of (ND)A was one of the other bases, the fluorescence intensity was very low. The fluorescence emission spectrum of (ND)A overlapped with the fluorescence excitation spectrum of fluorescein in the wavelength range of 400-500 nm. Thus, we designed FRET-BDF probes containing (ND)A as the FRET donor and fluorescein as the acceptor. The interaction of these two fluorophores, which are separated by defined base pairs, allowed an efficient energy transfer that resulted in a dominant fluorescence emission of fluorescein at 520 nm when using an excitation wavelength of 350 nm. Fluorescence emission from FRET-BDF probes was observed only when the complementary base of (ND)A is C, thus achieving a clear distinction of a C base on the complementary DNA strand. However, the general utility of our method is limited due to the quenching of the (ND)A fluorescence by a G/C base pair flanking (ND)A.

Base Pairing↗

Fluorescein angiography of the choroid in health and disease.

Fluorescein angiography of the normal fundus reveals the segmental nature of the choroidal vascular bed. Despite the presence of anatomically demonstrable anastomoses, a segmental distribution is present in vivo up to the choriocapillaris level. Choroidal vascular diseases manifest by localized of diffuse delayed or incomplete filling of the choroid and by the involvement of the overlying retinal pigment epithelium. In the acute phase of choroidal arterial occlusive disease, ophthalmoscopy reveals localized or diffuse edema. Fluorescein angiography of such cases initially shows a delayed perfusion of the involved area followed later on by fluorescein leakage. This late diffusion of the dye is probably related to alterations of the retinal pigment epithelial barrier. The extent of the lesion after resolution of the edema mainly depends on the site and the extent of the occlusion, on the development of collaterals and possibly on the involvement of the choroidal venous circulation. Ophthalmoscopy and fluorescein angiography will reveal localized or diffuse pigmentary changes, sometimes of quite characteristic aspect. This may be associated with local destruction of the choriocapillaris, although normalization of choroidal blood flow may also be observed. Chronic choroidal vascular insufficiency is a possible cause for choroidal sclerosis. Chronic choroidal ischemia is also a possible explanation for peripheral pigmentary changes seen in the elderly.

Adult↗

Impaired blood flow and arterio-venous shunting in human diabetic neuropathy: a novel technique of nerve photography and fluorescein angiography.

New techniques of sural nerve photography and fluorescein angiography which are able to provide an index of nerve blood flow have been developed. Under local anaesthetic, 3 cm of sural nerve was exposed at the ankle using an operating microscope. Without disturbing the epineurium, vessels were identified and photographed at a standard magnification (x 30). These were independently graded by an ophthalmologist not otherwise involved with the study. Fluorescein angiography was then carried out on the exposed nerve. The fluorescein appearance time and intensity of fluorescence were quantified, using computer analysis of digitised images. Thirteen subjects with chronic sensory motor neuropathy, five non-neuropathic diabetic and nine normal control subjects were studied. The mean epineurial vessel pathology score of the neuropathic group was significantly higher than the combined normal control and non-neuropathic diabetic groups (p < 0.01). Direct epineurial arteriovenous shunting was observed in six neuropathic and one non-neuropathic diabetic patients and not in any of the normal control subjects. The nerve fluorescein appearance time was significantly delayed in subjects with chronic sensory motor neuropathy (51.5 +/- 12 s) compared to both normal (34.7 +/- 9 s, p < 0.01) and non-neuropathic diabetic subjects (33.4 +/- 11 s, p < 0.025). The mean intensity of fluorescence at 96, 252 and 576 s, was significantly lower in subjects with chronic sensory motor neuropathy compared with both of the other groups (p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Arteries↗

[Simultaneous fluorescein and indocyanine green angiography with a confocal laser ophthalmoscope].

BACKGROUND: We report on our clinical experience with a recently developed confocal scanning laser ophthalmoscope for simultaneous fluorescein and indocyanine-green (ICG) angiography. MATERIALS AND METHODS: Following injection of fluorescein and ICG mixed in one syringe simultaneous confocal scanning laser fluorescein and ICG angiography were carried out using the Heidelberg Retina Angiograph (HRA). An argon laser (488 nm) and a diode laser beam (795 nm) from an external source were delivered via single-mode fibers. Emission was recorded between 500 and 650 nm and above 810 nm, respectively. Digital images were displayed simultaneously on a monitor during angiography. RESULTS: A total of 295 simultaneous angiograms in 268 patients with various retinal and choroidal diseases, including exudative age-related macular degeneration with occult and classic choroidal neovascularization, were obtained. High-contrast images during all phases of the angiography were obtained. Besides mild side effects in similar frequency known from individual injections, no additional toxic or allergic reactions from simultaneous injections of the two dyes were observed. CONCLUSIONS: Confocal laser scanning angiography allows for simultaneous fluorescein and ICG angiography. Compared with consecutive investigations using both dyes, simultaneous angiography requires only one injection, and offers identical digital frames. Simultaneous injection is not associated with additional side effects.

Aged↗

Fluorescein and indocyanine green angiography in ocular toxoplasmosis.

PURPOSE: To document fluorescein and indocyanine green angiographic findings in patients with ocular toxoplasmosis. METHODS: Charts of patients with ocular toxoplasmosis who were evaluated with fluorescein and indocyanine green angiograpy were reviewed. RESULTS: In this study, eight (38%) females and 13 (62%) males with a mean age of 20.3 years were included. Of the 21 patients, five (24%) had bilateral involvement with active or inactive toxoplasmic lesion. There were active lesions in 12 (46%) eyes and inactive lesions in 14 (54%) eyes. Indocyanine green angiograpy showed hypofluorescence of the active and inactive retinochoroiditis lesions at all phases. Hypofluorescent multiple satellite dark dots were observed in 11 (92%) eyes with active retinochoroiditis and in two (14%) eyes with inactive lesions. In two patients with unilateral active toxoplasmic retinochoroiditis, hyperfluorescent plaques were observed in the fellow eyes on indocyanine green angiograpy. The fundus examination and fluorescein angiography of the fellow eyes were normal and had a visual acuity of 10/10. Choroidal neovascularization was observed in two (8%) eyes. In eyes with active inflammation, fluorescein angiography revealed early hypo-fluorescence and late intense hyper-fluorescence with fuzzy margins of the retinochoroiditis lesion (12 eyes), hyperfluorescence of the optic nerve head (four eyes) and leakage from the vessels and/or vascular sheathing (four eyes) and neuroretinitis (one eye). CONCLUSION: Toxoplasmic retinochoroiditis is a more widespread inflammation than visible fundus lesions. Indocyanine green angiography is a useful method for evaluating the amount of inflammatory activity and late complications in patients with ocular toxoplasmosis.

Adolescent↗

Comparison of fluorescein and indocyanine green angiography in angioid streaks.

BACKGROUND: The main cause of vision loss in patients with angioid streaks is choroidal neovascularization and subsequent macular degeneration. Indocyanine green angiography allows visualization of the choroidal circulation and may be superior to fluorescein angiography in the evaluation of patients with angioid streaks. METHODS: The ophthalmoscopic, fluorescein and indocyanine green angiographic characteristics of angioid streaks were studied in 34 patients with such streaks. Nineteen patients had pseudoxanthoma elasticum and 15 patients had isolated angioid streaks. The fluorescence characteristics of the 'peau d'orange' and of choroidal neovascularization, when present, were also analyzed. RESULTS: Angioid streaks may be hyperfluorescent, hypofluorescent or invisible on indocyanine green angiography. Hyperfluorescent streaks were found in 88% of eyes, hypofluorescent streaks in 11%; in 18% of eyes some streaks were not visualized by indocyanine green angiography. The peau d'orange stained as a speckled pattern in the midperiphery; the flecks were concentrated temporal to the macula. Eighteen eyes presented classic and 6 occult choroidal neovascularization. In several eyes a plaque-like lesion was seen on indocyanine angiography that did not correspond to occult choroidal neovascularization on fluorescein angiography. CONCLUSION: Indocyanine angiography outlines angioid streaks as well as the peau d'orange appearance better than fluorescein angiography in the majority of cases. In some cases, however, funduscopically visible streaks can not be visualized. Sometimes classic choroidal neovascular membranes are not visualized by conventional indocyanine green angiography. Occult choroidal neovascularization is better defined by indocyanine green angiography. The fluorescence of angioid streaks and of plaque-like lesions makes the interpretation of indocyanine green angiography difficult.

Adult↗

Independent diagnostic value of fluorescein angiography in the evaluation of intraocular tumors.

BACKGROUND: Fluorescein angiography has been used in the clinical evaluation of suspected neoplastic lesions of the ocular fundus for over 30 years. Yet, the independent diagnostic value of this photographic technique in patients with suspected intraocular neoplasms has never been determined. METHODS: The authors evaluated color fundus photographs and fluorescein angiograms of 50 mass lesions of the ocular fundus. The cases were chosen to reflect a broad spectrum of lesions, including choroidal malignant melanoma, choroidal nevus, circumscribed choroidal hemangioma, metastatic carcinoma to the choroid, miscellaneous other neoplasms, hamartomas, or choristomas, and non-neoplastic lesions simulating neoplasms. Ten experienced retinal specialists independently reviewed the angiograms (presented in random order without the corresponding color fundus photographs) and rendered a diagnosis. Approximately 1 month later, each retinal specialist independently reviewed the color fundus slides (presented in a different random order without the corresponding fluorescein angiograms) and again rendered a diagnosis for each lesion. RESULTS: The accuracy of angiographic diagnosis by the different reviewers ranged from 16% to 56% (average 45.4%), while that based on review of the color fundus slides ranged from 32% to 78% (average 59.0%). This difference is statistically significant. CONCLUSION: Fluorescein angiography alone did not appear to be a reliable method for establishing the clinical diagnosis of neoplasms and simulating lesions of the ocular fundus.

Carcinoma↗

Loss of fluorescein across the conjunctiva.

The rate of disappearance from the tear film of fluorescein and rhodamine dextran instilled together into the human eye was compared. In many cases fluorescein disappeared more rapidly, which was attributed to its penetration across the conjunctival surface. A corresponding mean fluorescein permeability across this surface of 2.5 x 10(-5) cm min-1 was calculated. This route of loss of fluorescein from the tears leads to an average overestimate of tear turnover of 25%.

Adult↗

Evaluation of the toxicologic and teratogenic potentials of sodium fluorescein in the rat.

Sodium fluorescein (10%) when injected intravenously (5 ml/kg) in pregnant albino rats crossed the placental barrier and appeared to be distributed throughout the fetus within 15 min. It was detectable in the fetus up to 4 h after injection but not beyond 24 h. A single intravenous administration of sodium fluorescein did not produce embryotoxic or teratogenic effects. Oral LD50 studies using sodium phenobarbital on rats which received sodium fluorescein during their fetal development showed no apparent effects of sodium fluorescein on their drug detoxification systems.

Abnormalities, Drug-Induced↗

A fluorimetric method using fluorescein di-beta-D-galactopyranoside for quantifying the senescence-associated beta-galactosidase activity in human foreskin fibroblast Hs68 cells.

The senescence-associated beta-galactosidase (SA-betaG) assay is one of the few accepted markers of cell aging. However, the cytochemical method using 5-bromo-4-chloro-3-indolyl beta-D-galactopyranoside (X-Gal) as substrate is limited in sensitivity and is only semiquantitative. Here, we modified the X-Gal method by replacing X-Gal with fluorescein di-beta-D-galactopyranoside (FDG) as substrate for SA-betaG, and the activity was measured fluorimetrically. We showed in Hs68 cells that the FDG fluorescein fluorescence increased with increasing passages of the cells in parallel with the X-Gal method. A major advantage of the FDG method is that it is a quantitative method for the SA-betaG activity. For example, we showed that the FDG fluorescein in p30(+1) of Hs68 cells was generally stronger than that in p26(+1) cells, whereas the X-Gal method gave similar results (95 and 100%) for p26(+1) and p30(+1) cells. The FDG method was precise with a relative standard deviation lower than 10%. We further demonstrated that FDG and X-Gal could be added simultaneously for SA-betaG assay because the FDG fluorescein diffused readily through formaldehyde-fixed cell membrane and could be detected in the suspension buffer. Thus, a double-substrate method, i.e., X-Gal for rapid qualitative assay and FDG for quantitative assay, can be conducted simultaneously to provide a simple and reliable assay of SA-betaG activity as a marker of cell aging.

Cellular Senescence↗

Fluorescein isothiocyanate-hapten immunoassay for determination of peptide-cell interactions.

We have developed a fluorescein isothiocyanate (FITC)-hapten immunoassay, where a FITC-labeled peptide binding to a cell is assayed as the amount of immunoreactive fluorescein present in a cell lysate. An antifluorescein-horseradish peroxidase conjugate binds to either a fluoresceinated peptide in the lysate or a fluorescein attached to the wells of a microtiter plate in a competitive fashion. After washing, solid-phase peroxidase activity is measured and inversely related to the amount of FITC-labeled peptide present. To demonstrate the assay, the interaction of a FITC-labeled bombesin-like peptide with the gastrin-releasing peptide receptor on PC-3 and HT-29 cells was investigated. Using PC-3 cells, we obtained similar displacement curves and numbers of binding sites per cell by both the FITC-hapten immunoassay and a reference radioreceptor assay. The FITC-hapten immunoassay is a sensitive and versatile method, since the same commercially available reagents can be used to assess interactions between any peptide and any receptor. In addition, the FITC-labeled peptide can be used to visualize receptors in fluorescent-activated cell sorting or fluorescent microscopy.

Bombesin↗

Ultra-wide-field fluorescein angiography of the ocular fundus.

PURPOSE: To evaluate the clinical applicability of a novel scanning laser ophthalmoscopy imaging system for ultra-wide-field fluorescein angiography. DESIGN: Observational case report. METHODS: Wide-field fluorescein angiography images were captured in normal volunteers and in patients with a variety of clinical disorders with a newly developed scanning laser ophthalmoscope (Optomap; Optos PLC., Dunfermline, Scotland, United Kingdom) that produces high-resolution images of the fundus up to a 200-degree field. Fluorescein angiograms were performed using standard sequence times. RESULTS: Peripheral vascular perfusion of all four quadrants of a normal fundus was observed with good detail of the capillary architecture. Patients with diabetes and ocular inflammatory eye disease showed evidence of peripheral retinal nonperfusion. The relative degrees of retinal perfusion and nonperfusion could be compared in single images. CONCLUSIONS: Ultra-wide-field fundus fluorescein angiography offers the possibility of evaluating and quantitating peripheral retinal perfusion and vascular pathology in fundus disease.

Fluorescein Angiography↗

Fluorescein transport properties across artificial lipid membranes, Caco-2 cell monolayers and rat jejunum.

Membrane transport characteristics of a paracellular permeability marker fluorescein were evaluated using artificial membrane, Caco-2 cell monolayers and rat jejunum, all mounted in side-by-side diffusion cells. Modified Ringer buffers with varied pH values were applied as incubation salines on both sides of artificial membrane, cell culture monolayers or rat jejunum. Passive transport according to pH partition theory was determined using all three permeability models. In addition to that, active transport of fluorescein in the M-S (mucosal-to-serosal) direction through rat jejunum was observed. The highest M-S P(app) values regarding the active transport through the rat jejunum were observed in incubation saline with pH 6.5. Fluorescein transport through the rat jejunum was inhibited by DIDS (4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid) and alpha-CHC (alpha-cyano-4-hydroxycinnamic acid). Thus, we assume that two pH-dependent influx transporters could be involved in the fluorescein membrane transport through the intestinal (jejunal) epithelium. One is very likely an MCT (monocarboxylic acid cotransporter) isoform, inhibited by specific MCT inhibitor alpha-CHC, while the involvement of the second one with overlapping substrate/inhibitor specificities (most probably a member of the organic anion-transporting polypeptide family, inhibited at least partially by DIDS) could not be excluded.

4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid↗

The potential of nasal application for delivery to the central brain-a microdialysis study of fluorescein in rats.

Previous animal studies have shown that various types of nasally administered drugs and model substances can access the central nervous system (CNS) via direct transport across the olfactory epithelium, and thereby circumventing the blood-brain barrier (BBB). These compounds, however, have mainly been identified in the cerebrospinal fluid and the olfactory bulbs which are usually not pharmacologically relevant targets. The aim of the present study was to evaluate the potential of targeting the central brain by olfactory absorption by use of sodium fluorescein as a hydrophilic model substance with limited permeability across the blood-brain barrier. Microdialysis probes were implanted in blood and in right and left side of the brain (striatum) in rats. The pharmacokinetics of sodium fluorescein was studied from 0 to 180min following intravenous and unilateral nasal administration without occlusion of the oesophagus. Pharmacokinetic modelling showed a significantly higher absorption rate and lower T(max) in the ipsilateral striatum (0.097min(-1) and 41min) compared with the contralateral side (0.056min(-1) and 54min). The rate of elimination in brain was significantly lower after nasal administration (0.004min(-1)) compared with intravenous administration (0.012min(-1)). However, the brain to plasma area under the curve ratios of model substance were low (2-3%) and not significantly different between right and left side of the brain, regardless of the route of administration. The results obtained by microdialysis were supported by findings in whole brain homogenates where concentrations of fluorescein were approximately 40% higher in the right striatum compared with the left side initially after nasal administration to the right nostril of rats. Despite some indications of olfactory transport to the central rat brain it was concluded that the drug targeting potential of sodium fluorescein and most likely other hydrophilic compounds is limited.

Administration, Intranasal↗

Cochlear microdialysis for quantification of dexamethasone and fluorescein entry into scala tympani during round window administration.

Before new drugs for the treatment of inner ear disorders can be studied in controlled clinical trials, it is important that their pharmacokinetics be established in inner ear fluids. Microdialysis allows drug levels to be measured in perilymph without the volume disturbances and potential cerebrospinal fluid contamination associated with fluid sampling. The aims of this study were to show: (i) that despite low recovery rates from miniature dialysis probes, significant amounts of drug are removed from small fluid compartments, (ii) that dialysis sampling artifacts can be accounted for using computer simulations and (iii) that microdialysis allows quantification of the entry rates through the round window membrane (RWM) into scala tympani (ST). Initial experiments used microdialysis probes in small compartments in vitro containing sodium fluorescein. Stable concentrations were observed in large compartments (1000 microl) but significant concentration declines were observed in smaller compartments (100, 10 and 5.6 microl) comparable to the size of the inner ear. Computer simulations of these experiments closely approximated the experimental data. In in vivo experiments, sodium fluorescein 10 mg/ml and dexamethasone-dihydrogen-phosphate disodium salt 8 mg/ml were simultaneously applied to the RWM of guinea pigs. Perilymph concentration in the basal turn of ST was monitored using microdialysis. The fluorescein concentration reached after 200 min application (585+/-527 microg/ml) was approximately twice that of dexamethasone phosphate (291+/-369 microg/ml). Substantial variation in concentrations was found between animals by approximately a factor of 34 for fluorescein and at least 41 for dexamethasone phosphate. This is, to a large extent, thought to be the result of the RWM permeability varying in different animals. It was not caused by substance analysis variations, because two different analytic methods were used and the concentration ratio between the two substances remained nearly constant across the experiments and because differences were apparent for the repeated samples obtained in each animal. Interpretation of the results using computer simulations allowed RWM permeability to be quantified. It also demonstrated, however, that cochlear clearance values could not be reliably obtained with microdialysis because of the significant contribution of dialysis to clearance. The observed interanimal variation, e.g., in RWM permeability, is likely to be clinically relevant to the local application of drugs in patients.

Animals↗

Fluorescein angiographic findings in ocular siderosis.

PURPOSE: To report a case of siderosis from a retained intraocular iron foreign body manifesting localized retinal capillary nonperfusion documented by fluorescein angiography. METHODS: Case Report. In a 35-year-old man with decreased vision in the left eye, studies included fundus photography, fluorescein angiography, visual field testing, and electrophysiology. Surgical foreign body extraction and histopathologic examination were performed. RESULTS: Preoperatively, in the left eye, humphrey visual fields and electrophysiology testing revealed marked depression. Fluorescein angiography demonstrated nasal capillary nonperfusion with occlusion of the second- and third-order arterioles extending along a gradient from the foreign body. Microscopic examination of the lens capsule confirmed the diagnosis of siderosis secondary to a retained iron foreign body. CONCLUSION: Extensive capillary nonperfusion may be associated with a retained iron intraocular foreign body, as documented by fluorescein angiography.

Adult↗