Nano-sized water-in-oil-in-water emulsion enhances intestinal absorption of calcein, a high solubility and low permeability compound.

Our goal was to develop safe and stable multilayer emulsions capable of enhancing intestinal absorption of biopharmaceutics classification system (BCS) class III drugs. First, w/o emulsions were prepared using calcein as a model BCS class III compound and condensed ricinoleic acid tetraglycerin ester as a hydrophobic emulsifier. Then water-in-oil-in-water (w/o/w) emulsions were prepared with shirasu porous glass (SPG) membranes. Particle size analyses and calcein leakage from oil droplets in w/o/w emulsions led us to select stearic acid hexaglycerin esters (HS-11) and Gelucire 44/14 as hydrophilic emulsifiers. Analyses of the absorption-enhancing effects of w/o/w emulsions on intestinal calcein absorption in rats showed that calcein bioavailability after intraduodenal (i.d.) administration of HS-11 or Gelucire 44/14+polyvinyl alcohol (PVA) w/o/w emulsions prepared with 0.1-microm pore-sized SPGs was significantly higher than that of the calcein control. However, serum calcein concentration vs. time profiles after i.d. administration of w/o/w emulsions prepared with 1.1-microm and 30-microm pore-sized SPGs and an emulsion prepared with a calcein-containing outer water phase were comparable to control profiles. These results suggested that HS-11 or Gelucire 44/14+PVA are safe outer water phase additives and that 0.1-microm pore-sized SPGs are important for preparing w/o/w emulsions that enhanced intestinal calcein absorption.

Intraoperative fluorescence staining of malignant brain tumors using 5-aminofluorescein-labeled albumin.

OBJECTIVE: The newly developed conjugate 5-aminofluorescein (AFL)-human serum albumin (HSA) was investigated in a clinical trial for fluorescence-guided surgery of malignant brain tumors to assess its efficacy and tolerability. METHODS: AFL, covalently linked to human serum albumin at a molar ratio of 1:1, was administered intravenously 0.5 to 4 days before surgery at 0.5 or 1.0 mg/kg of body weight to 13 patients aged 38 to 71 years who were suspected of having malignant gliomas. Fluorescence guidance using a 488-nm argon laser was performed during surgery at will. The extent of tumor resection was verified by early postoperative magnetic resonance imaging. Fluorescent and nonfluorescent samples were collected for neuropathology. Blood samples for laboratory and pharmacokinetic analyses were taken over the course of 4 weeks. RESULTS: Fluorescence staining of tumor tissue was bright in 11 patients (84%), resulting in complete resection of fluorescent tumor tissue in 9 patients (69%). In 2 patients, residual fluorescent tumor tissue was also confirmed by magnetic resonance imaging. Neither bleaching nor penetration of AFL-HSA into the surrounding brain edema or into necrotic tissue was seen. The agreement between fluorescence and histopathology in tumor samples and samples of the tumor border was 83.3%. There were no toxic side effects. The quality of fluorescence was independent of the dose administered. The optimal time for surgery is between 1 and 4 days after AFL-HSA administration. CONCLUSION: Tumor fluorescence using AFL-HSA made fluorescence-guided brain tumor resection possible, demonstrating that albumin is a suitable carrier system for selective targeting of aminofluorescein into malignant gliomas.

Validity of fluorexon disodium versus sodium fluorescein for use in Goldmann tonometry.

PURPOSE: To evaluate the safety, validity, and comfort of 0.35% fluorexon disodium and 0.4% benoxinate (Flura-Safe) compared with the gold standard of 0.25% sodium fluorescein and 0.4% benoxinate for Goldmann applanation tonometry (GAT). METHODS: This was a double-masked, randomized, crossover clinical trial. Subjects received either the standard or study formulation for GAT on visit 1 and the other formulation 1 week later. At each visit, tonometer mire quality, adequacy of fluorescence, ease of intraocular pressure (IOP) measurements, the IOP value, and anesthetizing efficacy of the formulation were assessed. Subjects graded general comfort, soreness and irritation, and burning and stinging of each formulation at 1 and 5 minutes after drop instillation. RESULTS: Sixty-seven subjects completed the study. The mean IOP was 13.9 +/- 2.7 with fluorexon and 13.9 +/- 2.8 mm Hg with fluorescein OD and 14.0 +/- 2.8 with fluorexon and 13.9 +/- 2.5 mm Hg with fluorescein OS. The measurements with the 2 formulations were highly correlated for OD and OS, and the differences between the 2 measurements were not clinically significant. There was also no significant difference between the 2 drops in mire clarity, adequacy of fluorescence, or corneal anesthesia. However, fluorexon was statistically more comfortable (P = 0.039) and caused less stinging and burning (P = 0.014) at 1 minute versus the fluorescein formulation. CONCLUSION: Not only was the new fluorexon product accurate and effective in GAT, it was also statistically more comfortable and had a less stinging and burning effect at 1 minute after drop instillation than the traditional fluorescein formulation. Because fluorexon is less likely to stain soft contact lenses, this may be the dye-anesthetic formulation of choice for practices that routinely perform GAT.

Photodynamic therapy for wound-healing modulation in pterygium surgery. A clinical pilot study.

BACKGROUND: This study was performed to evaluate the safety and efficacy of photodynamic therapy with the carboxyfluorescein ester BCECF-AM as an adjunctive treatment procedure for pterygium surgery to reduce the rate of recurrence. METHODS: In this nonrandomized prospective clinical trial, 19 eyes with nasally located primary pterygium were examined. All eyes were treated with the bare sclera surgical technique. Seven eyes received in addition treatment with BCECF-AM solution and blue light. All patients were evaluated at least after 1 day, 1 week, 1 month, 3 months, and 1 year. Postoperative fibrovascular growth from the limbus of at least 1 mm was defined as recurrence. RESULTS: The intraoperative application of BCECF-AM solution did not cause anterior chamber flare or any other significant side effects. The bare sclera surgery rate of recurrence was 0% (zero of 12) after 3 months and 91% (11 of 12) after 1 year. The additional photodynamic therapy treatment had a rate of recurrence of 14.2% (one of seven) after 3 months and 71.4% (five of seven) after 1 year. CONCLUSIONS: The applied PDT technique seems to be a safe procedure but is associated with a high rate of recurrence. In conclusion, the evaluated PDT treatment procedure, at this point, should not be considered. As we found a high rate of recurrence also in the control group, the bare sclera technique is not effective, even in primary pterygia.

[The adverse reactions and treatment of fundus fluorescein angiography].

PURPOSE: To investigate the safety of fluorescein angiography and to evaluate the examination. METHODS: We retrospectively analyzed 8 344 patients who underwent fluorescein angiography in our hospital in the past four years. The rate of adverse events was calculated and the emergency management for severe cases was discussed. RESULTS: There were 693 cases (8.3%) of adverse events occurring in the patients. Many of them were mild or moderate ones, which were 664 cases in number and were 7.87% in rate. The other 29 cases (0.35%) were severe ones. No special treatment was needed for the mild or moderate adverse events, the symptoms can be relaxed by deep breathing or having a rest for a moment. The symptoms of the severe adverse events can be relieved through anti-hypersuscepibility treatments and no sequelae left. No case of death occurred. CONCLUSION: The adverse events could occur in fluorescein angiography examination. It suggests that we should pay attention to it and be aware of the system conditions of the patients. It is also important for us to grasp the indications and contraindications and to prepare for the emergent events. In summary, fluorescein angiography is generally a safe method for the examination of fundus disease.

Photodynamic modulation of wound healing in glaucoma filtration surgery.

AIM: To report a clinical pilot study investigating photodynamic therapy (PDT) in combination with glaucoma filtration surgery. BCECF-AM was used as the photosensitising substance. The clinical safety and tolerability of BCECF-AM, and its efficacy in controlling postoperative intraocular pressure (IOP) were assessed. METHODS: Before trabeculectomy (TE), 42 consecutive eyes of 36 glaucoma patients received one subconjunctival injection of 80 micro g BCECF-AM (2,7,-bis- (2-carboxyethyl) -5- (and-6) -carboxy-fluorescein, acetoxymethyl-ester) followed by an intraoperative illumination with blue light (lambda = 450-490 nm) for 8 minutes. Antifibrotic efficacy was established as postoperative IOP reduction of >20% and/or an IOP constantly < 21 mm Hg without antiglaucomatous medication. Follow up of the filtering bleb was documented by slit lamp examination. RESULTS: Eyes had mean 1.1 preoperative surgical interventions (filtration and non-filtration glaucoma surgery). Mean preoperative IOP was 31.6 (SD 9.7) mm Hg. Patients were followed for mean 496 days (range 3.5-31.8 months). Of the 42 eyes, 25 eyes had an IOP decreased to 15.8 (3.4) mm Hg without medication (complete success: 59.5%; p<0.001; t test). Seven eyes showed good IOP reduction < 21 mm Hg under topical antiglaucomatous medication (qualified success: 16.7%). 10 eyes failed because of scarring within 2-67 weeks (23.8%). Clinical follow up examinations revealed no local toxicity, no uveitis, and no endophthalmitis. CONCLUSIONS: This method is a new approach in modulating postoperative wound healing in human eyes undergoing glaucoma filtration surgery. The data of the first human eyes combining TE with PDT underline the clinical safety of this method and its possible potential to prolong bleb survival.

Ethnic variation in fluorescein angiography induced nausea and vomiting.

PURPOSE: A prospective survey was undertaken to investigate ethnic variations in the frequency of nausea and vomiting after fundus fluorescein angiography (FFA). METHOD: Between May and September 1998, 197 adult patients were recruited to the study. A questionnaire containing closed-ended questions was completed by nurses after each FFA and a questionnaire was given to patients to complete 5 hours after the procedure at home. Patients' anxiety level was measured before FFA using a 5-item ordinal response scale. RESULTS: Results indicate that patients from black, Asian, Chino-Asian and mixed ethnic origins are significantly more likely to vomit and feel nauseous immediately after the administration of fluorescein dye. Patients with a history of nausea after FFA are significantly more likely to feel nauseous again after repeat FFA. CONCLUSION: Ethnic origin and a previous history of nausea and vomiting appear to be important factors in FFA-induced nausea and vomiting. The results of this study have led the investigators to develop a protocol for the prophylactic treatment of nausea and vomiting following FFA.

Phototoxic reactions caused by sodium fluorescein.

PURPOSE: To report three cases of phototoxic reactions to intravenous fluorescein for retinal angiography and to describe provocative testing in a volunteer. METHODS: Three patients with phototoxic reactions were interviewed, and one volunteer underwent a controlled challenge test by applying a potent sunscreen and exposing skin areas to direct sunlight before and after fluorescein administration. RESULTS: All patients experienced marked cutaneous erythema, edema, and pain to sun-exposed areas within 1 hour of exposure. The reaction faded during a variable period of time, and one case resulted in mild epidermal desquamation and prolonged discomfort. We noted minimal skin changes in the volunteer who was exposed to the sun before fluorescein administration; however, marked blanching erythema and pain were noted after fluorescein administration and sunlight. CONCLUSIONS: Consistent with its in vitro properties as a photodynamic dye, fluorescein may rarely act as a phototoxic agent in humans at doses employed for fluorescein angiography.

[Anaphylactic shock caused by application of fluorescein on the ocular conjunctiva]. / Choc anaphylactique par application de fluorescéine sur la conjonctive oculaire.

OBJECTIVE: Fluorescein is widely used in ophthalmology. Side effects related to fluorescein occur frequently but are usually benign (nausea, vomiting, lipothymia). Severe side effects are rare. We report a case of anaphylactic shock due to local application of fluorescein. CASE REPORT: A 70-year-old woman was treated for ocular conjunctivitis with local application of fluorescein. Cardiac arrest occurred due to anaphylactic shock. Resuscitation was successful. DISCUSSION: The gravity of certain complications related to the use of fluorescein underline the importance of adequate resuscitation material and adapted treatment.

[Usefulness of the prick test for anaphylactoid reaction in intravenous fluorescein administration].

We examined whether a prick test was a valuable method in comparison with an intradermal skin test for predicting an anaphylactoid reaction to intravenous injection of fluorescein solution. Fifteen hundred cases were tested. The number (rate) of positive reactions to the prick test with 10% and 1.0% fluorescein solution was 2 (0.1%) and 0 (0.0%), respectively. In contrast, positive reaction to the intradermal skin tests with 10% and 0.1% fluorescein solution was observed in 686 cases (45.7%) and 13 cases (0.9%), respectively. Fluorescein angiography (FAG) was performed in 1,499 of the 1,500 cases. Adverse reactions such as nausea, cough, cold sweat, urticaria, and shock were noted in 85 cases (5.7%). Typical anaphylactoid shock occurred in one case (0.07%), which was one of the two cases positive to the prick test with 10% fluorescein. In the other positive prick test case, FAG was cancelled because of the high probability of anaphylactoid shock. The results suggest that a prick test with 10% fluorescein solution can markedly cut down the false positive reactions and can be a useful test for the prospective diagnosis of anaphylactoid reactions to intravenous fluorescein administration.

Photosensitivity reaction to intravenously administered fluorescein.

Sodium fluorescein is an organic dye widely used as a diagnostic aid. This article reports a case of a photosensitivity reaction associated with intravenous administration in a healthy volunteer. To our knowledge, this is the 1st case of a photosensitivity reaction of the immediate type due to fluorescein reported in the literature, which probably indicates its very low incidence. The literature on photosensitization to fluorescein is reviewed.

Adverse reactions during retinal fluorescein angiography.

BACKGROUND: Fast sequence retinal fluorescein angiography is a commonly employed diagnostic procedure within the optometric practice with relatively few serious adverse reactions. A retrospective study was conducted to document the incidence of adverse reactions with this procedure. METHODS: A total of 1,173 patient charts who had undergone intravenous injection for retinal fluorescein angiography at a specility referral clinic or a referral clinic at a school of optometry. All patients had been intra-venously injected with 500 mg of sodium fluorescein in 25% or 10% solution. Adverse reactions were noted within the charts. RESULTS: The most common adverse reaction were nausea (.8% of patients) and urticaria (.6% of patients), with other reactions including emesis and hypoglycemia. Extravasation of dye was noted in .2% of patients. No acute anaphylaxis was noted. CONCLUSIONS: Fast sequence retinal fluorescein angiography is a relatively safe diagnostic test. However, one should be prepared to handle acute anaphylaxis within the office before administering the test because of previously published cases of life-threatening reactions.

Hemolytic anemia associated with injection of fluorescein.

A 49-year-old woman presented with a hemoglobin level of 9.5 g per dL (95 g/L), reticulocyte count of 6.7 percent (0.067), and hemoglobinuria. The next day, the hemoglobin had dropped to 5.8 g per dL (58 g/L), and total bilirubin was 8.8 mg per dL (150 mumol/L). The serum reacted 2+ with all red cells (RBCs). The direct antiglobulin test (DAT) was 3+ with anti-IgG and 1+ with anti-C3, but eluates prepared by two different methods did not react with untreated RBCs. The eluate reacted 2+ with amoxicillin-coated RBCs; amoxicillin had been listed in the patient's record as a previous medication. The patient denied recent ingestion of amoxicillin. Further investigation documented the injection of a dye, fluorescein sodium (AK-FLUOR-25%), for a ophthalmologic fluorescein angiographic study 2 days before admission. RBCs coated with AK-FLUOR reacted with the eluate. Controls consisting of normal serum, an eluate prepared from DAT-negative RBCs, and a serum known to contain anti-penicillin did not react with AK-FLUOR-coated RBCs. Nine days later, the DAT was negative and the serum did not react with untreated RBCs. In the presence of AK-FLUOR (1-in-125) or amoxicillin (1 mg/mL), the serum reacted 2+ in the antiglobulin test. Antibodies to AK-FLUOR and amoxicillin appeared to react by two mechanisms, which is similar to results in recent reports of other drugs associated with hemolytic anemia. AK-FLUOR has not previously been reported to be associated with hemolytic anemia.

Enhancing effects of fluorescein on beta-lactam rash. I: High incidence of cefclidin rashes in an ophthalmological volunteer trial.

Disseminated maculopapular eruptions were frequently observed in a volunteer trial of cefclidin's use in ophthalmological and neurological examinations (8/12; 67%) It appeared at 8-12 days (mean +/- SD, 9.6 +/- 1.1 days) from the initiation of the trial and subsided within 1-2 days (mean +/- SD, 1.8 +/- 0.4 days). Patch testing with cefclidin produced a +/- reaction in 1 of 8 cases, and the drug-induced lymphocyte stimulation test (DLST) elicited a positive response (SI: 2.8) in 1 of 8 and a weakly positive response (1.8 < or = SI < 2) in 2 of 8. From these findings, it seems likely that the eruptions may be partially mediated by delayed type hypersensitivity (DTH) reactions to cefclidin. No such eruption was observed in the phase II trial of cefclidin where only 2.8% of 1.122 volunteers developed the eruption. The volunteers were given both fluorescein and oxybuprocain in their eyes to measure ocular tension on days -1, 0, 1, 3, 5, 7, 9, 11, 13 and weeks 3, 5, 7 after the initiation of cefclidin. Fluorescein and/or oxybuprocain may affect cefclidin to induce these abnormal reactions in the volunteers.

Enhancing effects of fluorescein on beta-lactam rash. II: Enhancing effects of fluorescein on generalized rash induced by beta-lactam antibiotics in guinea pigs.

Healthy volunteers, who were receiving intravenous injections of cefclidin (CFCL) with frequent concomitant use of fluorescein (F) and oxybuprocain (O) in the eyes for measurement of ocular tension, developed drug eruptions at the high frequency of 66.7%. The injection of CFCL alone induced the eruptions at an incidence of 2.8%. The cause of this high eruption rate was thought to be the simultaneous treatment with F and/or O. Therefore, we conducted experiments with CFCL-induced generalized rash (GR) in guinea pigs. Guinea pigs treated with F and O during both the phases of immunization and intraperitoneal elicitation developed CFCL rashes at a high frequency. This CFCL-rash was augmented by the treatment with F during either phase, but not by the treatment with O. Skin testing induced delayed type hypersensitivity (DTH) reaction to O in some animals, but the DTH to F was not induced in animals immunized with F in complete Freund's adjuvant. Furthermore, F augmented rashes induced not only by CFCL but also by other beta-lactam antibiotics such as cefsulodin and sulbenicillin. Accordingly, it is likely that F played a dominant role in the high incidence of drug eruptions during the volunteer trials with measurement of ocular tension.