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Permanent blue discoloration of a hydrogel intraocular lens by intraoperative trypan blue.

A 79-year-old white man had cataract surgery in the right eye with implantation of an Acqua intraocular lens (IOL) (Mediphacos). Trypan blue 0.1% was used during surgery to stain the anterior capsule and enhance the contrast during capsulorhexis. Seven days after surgery, the patient presented with "dark and double" vision (monocular diplopia). The IOL was decentered superiorly and appeared dark blue. The lens was explanted 2 months after surgery and sent for gross and microscopic analyses in a dry state and after hydration. The same analyses were performed on 2 unused lenses of the same design that had been immersed in diluted trypan blue solutions (0.01% and 0.001%). On the explanted lens, the dark blue staining was denser in the optic, especially in its periphery. The blue discoloration could not be removed after 24 hours of lens immersion in a balanced salt solution at 37 degrees C. Permanent staining of the unused lenses was also obtained after immersion in the trypan blue solutions.

Aged↗

Biomechanical changes in the anterior lens capsule after trypan blue staining.

PURPOSE: To examine the effect of trypan blue staining on the biomechanical behavior of the porcine anterior lens capsule. SETTING: Department of Ophthalmology, Technical University of Dresden, Dresden, Germany. METHODS: Fifty-five anterior lens capsules from porcine cadaver eyes were used. Two parallel 8.0 mm x 4.0 mm large capsule strips were prepared from each capsule. After trypan blue staining for various time intervals combined with exposure to white light (6000 lux) or with no light exposure, biomechanical stress-strain measurements were performed using an automated material tester. Untreated specimens and specimens treated with glutaraldehyde 0.1% were used as controls. The absorption spectrum of trypan blue 0.1% solution and the emission spectrum of the light source were measured. RESULTS: After treatment with light and trypan blue, at 25% strain, there was a statistically significant increase in stress of up to 70.1% and in elastic stiffness of 47% and a decrease in the ultimate mechanical strain of up to 13%. There were no biomechanical changes in capsules with trypan blue staining in the absence of light or after a short illumination time of 30 seconds, indicating a light-dependent process. After 30 minutes of glutaraldehyde 0.1% treatment, there was an increase in stress of 321.6% at 25% strain and a decrease in the ultimate strain of 47.6%. The emission spectrum of the light source included the absorption peak for trypan blue at 580 nm. CONCLUSIONS: Trypan blue staining of the lens capsule combined with light irradiation for at least 1 minute led to an increase in elastic stiffness at 25% strain and a reduction in the ultimate extensibility. This effect is probably due to the photosensitizing action of trypan blue, leading to light-induced collagen crosslinking of the capsule collagen similar to age-related crosslinking. Nucleus expression might be impeded by the increased capsule stiffness. Continuous curvilinear capsulorhexis is facilitated.

Animals↗

Studies on the mechanism of trypan blue teratogenicity in the rat developing in vivo and in vitro.

Trypan blue is a potent teratogen in vivo and in vitro in the rat. Many of the abnormalities produced by trypan blue--including swollen neural tube and pericardium, subectodermal blisters, hematomas, and generalized edema--may result from altered fluid balance in and around the embryo. The present study demonstrates relationships between changes in the fluid environment around the embryo and appearance of anomalies. Rat embryos were exposed in utero or in vitro to trypan blue during the early period of organogenesis. Both exposures resulted in defects that are typical of trypan blue treatment. Osmolality of exocoelomic fluid (ECF) was measured on gestation day 10 in vivo and day 12 in vitro, both after 48 hr of exposure to trypan blue. In both cases ECF osmolality was significantly lower than controls. This was correlated with the presence of edema-related anomalies in the embryo. On gestation day 11 in vivo, three days after maternal injection of trypan blue, ECF osmolalities were significantly higher than controls; however, there was tremendous variability in this parameter in day 11 treated embryos, and some had ECF osmolalities below the control range. Increased frequency of abnormalities was correlated with abnormal ECF osmolality, below and above the control range. Trypan blue probably exerts its teratogenic effects by disturbing the function of the visceral yolk sac. The movements of an amino acid and a monosaccharide across the visceral yolk sac were measured on gestation day 12 embryos in vitro. This aspect of yolk sac function was not altered by trypan blue exposure. Ultrastructure of the visceral yolk sac was observed after trypan blue exposure in vivo and in vitro. Endodermal cells in trypan blue-treated yolk sacs contained fewer large, electron dense lysosomes than controls. These were replaced by numerous small vacuoles, which may contain trypan blue. Trypan blue causes osmotic changes in the rat embryo in vivo and in vitro. These changes are correlated with embryonic malformations. Alterations in yolk sac ultrastructure indicate that trypan blue affects the function of this membrane.

Abnormalities, Drug-Induced↗

Histopathological analysis in experimental macular surgery with trypan blue.

AIM: To analyse the effect of trypan blue on the retina in an experimental setting of macular surgery. METHODS: Porcine eyes were used within 3 hours after death. The eyes were hemisected and the vitreous removed. Trypan blue (0.15%) was applied over the trephined posterior pole, whereas the rest of the eye cup was filled with a balanced salt solution (BSS). The dye and the BSS were removed after 1 minute and the complete eye cup irrigated and filled with fresh BSS. Both the treated and untreated retinas were illuminated with a standard surgical light pipe and source at maximum power for 10 minutes. Both the trypan blue exposed retina and the non-treated surrounding retina were processed for histology. RESULTS: Exposure of the retina to trypan blue for 1 minute, followed by illumination caused no histologically detectable damage compared to the controls. No microarchitectural disorganisation, cellular disruption, or affection of the vitreoretinal interface was detected. CONCLUSIONS: These findings indicate that a 1 minute exposure of trypan blue followed by illumination does not cause an acute morphologically detectable toxic effect on the porcine retina.

Animals↗

Biocompatibility of trypan blue with human corneal cells.

OBJECTIVE: To quantify the toxicity of trypan blue on human corneal cells according to exposure time and concentration. METHODS: Three in vitro experiments were performed. (1) We exposed cultured human corneal fibroblasts to trypan blue (0.0001% to 0.1%) in Eagle modified minimum essential medium (EMEM) or phosphate-buffered saline (PBS) for 15 minutes to 24 hours. Cytotoxicity was evaluated by Mosmann's colorimetric 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MMT) assay. (2) We exposed human corneas in EMEM for 24 hours to trypan blue (0.001% to 0.1%). Fellow donor corneas served as controls. Endothelial survival was evaluated morphologically and by cell density assessment. (3) We morphologically compared the endothelial viability of human donor corneas after exposure to 0.1% trypan blue for 5 to 30 minutes with control corneas. RESULTS: In experiment 1, trypan blue in EMEM was not significantly toxic at concentrations of 0.005% or lower. Higher concentrations were toxic only after exposure to trypan blue for at least 6 hours. In PBS, significant toxicity was found after exposure to 0.1% trypan blue for 30 minutes or longer. Lower concentrations were toxic after longer exposures. In experiment 2, exposure to 0.01% and 0.1% trypan blue for 24 hours resulted in significant loss in cell density. At lower concentrations, the endothelium was affected only morphologically. In experiment 3, endothelial morphology changed in control corneas and after exposure to 0.1% trypan blue for as little as 5 minutes. After 30-minute exposure, morphologic deterioration was more pronounced. CONCLUSIONS: Trypan blue was toxic in vitro to corneal endothelium and corneal fibroblasts at higher concentrations and notably longer exposure times. Toxicity was less in EMEM than in PBS. Clinical Relevance At commonly used concentrations, both during cataract surgery and in the cornea bank, trypan blue is safe for corneal cells. At higher concentrations or longer exposures, however, caution is warranted.

Biocompatible Materials↗

Direct effects of trypan blue on cardiac extracellular macromolecule synthesis.

The direct effects of the cardiac teratogen trypan blue on some parameters of embryonic chick heart metabolism were examined in vitro. Trypan blue inhibits chondroitin sulfate biosynthesis but stimulates incorporation of 3H-glucosamine into hyaluronate, heparin, and glycopeptides. 3H-fucose incorporation into glycoprotein is also stimulated. Total incorporation of 14C-labeled amino acids is elevated in the presence of trypan blue. Trypan blue does not cause qualitative changes in labeled end products; rather the metabolic alterations are quantitative. The possible exceptions are glucosamine-labeled glycoproteins since quantitative differences in glycopeptides could reflect qualitative differences in parent glycoproteins. These observations suggest that abnormal heart development, induced by trypan blue, may result from a multiplicity of metabolic alterations and not from any single chemical change.

Animals↗

Value of two mortality assessment techniques for organ cultured corneal endothelium: trypan blue versus TUNEL technique.

BACKGROUND/AIM: It is known that trypan blue staining is not a good predictor of loss of corneal endothelial cells (ECs) during organ culture. As it is primarily an indicator of membrane integrity, it would also not be expected to identify ECs undergoing apoptosis. The aim of this study was to determine the ability of the in situ TdT dUTP mediated nick end labelling (TUNEL) technique to detect cell death in the corneal endothelium caused by apoptosis during organ culture, compared with conventional vital staining with trypan blue. METHODS: 31 human corneas were organ cultured at 31C for 3-35 days. Staurosporine was used to induce apoptosis in five control corneas. The endothelium was assessed by trypan blue and by the in situ TUNEL technique. The percentages of trypan and TUNEL positive ECs were compared. Their links with sex, donor age, time from donor death and organ culture, initial and final EC density and cell loss were studied. RESULTS: TUNEL stained ECs were observed in all corneas. TUNEL positive ECs were mostly located either in corneal folds or at the periphery of corneal folds showing central shedding. The mean percentage of cell death at the end of storage, assessed by the trypan blue technique, was 1.47% (SD 2.63, range 0.03-12); assessed by the TUNEL technique it was 12.7% (SD 16.4 range 0.6-65.5). There was a significant correlation between the two techniques (r = 0.7, p<0.001). The percentage of TUNEL stained ECs was correlated negatively with EC density at the end of storage (r = -0.47, p <0.005) and positively with percentage EC loss during storage (r = 0.46, p < 0.05). CONCLUSION: This study demonstrates that organ cultured corneas systematically carry non-viable ECs that are implicated in cell death by apoptosis and go undetected when trypan blue staining is used. Because the in situ TUNEL assay detects earlier events in the cell death process than does trypan blue, it should be used to quantify endothelial viability, especially for experiments with new storage media.

Adult↗

Trypan blue in macular pucker surgery: an evaluation of histology and functional outcome.

PURPOSE: To evaluate possible adverse effects of trypan blue on the ultrastructure of the human retina, to report on functional outcome of macular pucker surgery with and without the use of trypan blue, and to evaluate the ultrastructure of tissue harvested during surgery. DESIGN: Experimental study and prospective matched-pair analysis of two consecutive, interventional case series. METHODS: Possible adverse effects on the ultrastructure of the human retina by trypan blue were evaluated in three donor eyes in an experimental study using trypan blue in concentrations of 0.02%, 0.15%, and 0.25%. The retinas were histologically evaluated. In the clinical study, the functional outcome (visual acuity, Goldmann perimetry) of 10 eyes of 10 consecutive patients with intraoperative use of trypan blue (0.15%) was analyzed (group 1) and compared with the functional outcome in a matched group of patients (preoperative visual acuity, pre- and postoperative lens status) who had undergone vitrectomy without trypan blue assistance (group 2). Only patients with an idiopathic macular pucker were included. Epiretinal tissue of all eyes was harvested and prepared for ultrastructural analysis using light and electron microscopy. RESULTS: In the postmortem study, no significant alterations of the inner retina suggesting adverse effects of trypan blue concentrations of 0.02% were observed. In contrast, a disorganization of the innermost retina and an absence of the internal limiting membrane (ILM) was seen after the application of undiluted 0.15% and 0.25% trypan blue. In the clinical study, the median best-corrected visual acuity was 20/50 in both groups (range, 20/200-20/40) before surgery. Mean age was 70 years in group 1 (with trypan blue) and 69 years in group 2 (without trypan blue). Mean follow-up time was 4 months in group 1 and 5.6 months in group 2. Postoperatively, median visual acuity had increased to 20/32 (range, 20/100-20/25; Wilcoxon test P = 0.01) in group 1 and to 20/40 (range, 20/100-20/25; P = 0.09) in group 2. The difference between the two groups was not statistically significant (P = 0.4). Four of 10 patients without and 7 of 10 patients with trypan blue staining experienced an improvement of visual acuity (gain of 2 lines or more). No postoperative visual field defects were noted in either group. Histologic analysis of tissue harvested intraoperatively revealed the regular picture of undisturbed fibrocellular membranes. In some specimens, a layer of interspersed collagen was noted between epiretinal cells and the ILM, suggesting two different morphologic types of macular pucker. In a few sections, areas of cellular elements were detected adjacent to the retinal surface of the ILM. CONCLUSION: Trypan blue in a concentration of 0.02% is not associated with morphologic alterations of the inner retinal layers in our postmortem study. After application of 0.15% and 0.25% trypan blue solutions, a disorganization of the inner retinal layers was observed; the ILM was absent. We did not find any adverse effects of an intraocular trypan blue concentration of 0.02% on functional status. Our study further indicates that the functional results of surgery with and without the use of trypan blue are comparable. As the question of toxicity of a dye can not be answered by morphological observations alone, further experimental studies will be needed.

Adult↗

Effects of trypan blue treatment on the immune responses of mice.

It has been reported that trypan blue treatment decreases the nonspecific resistance of mice to transplanted tumors and inhibits the in vitro cytotoxic activity of activated macrophages. We wished to determine whether this effect of trypan blue could be due to a selective inhibition of certain macrophage functions or whether it reflected a broader form of immunosuppression. We therefore tested the effects of trypan blue on a variety of immunological responses. Treatment of mice with trypan blue delayed their rejection of skin allografts and transplants of a highly antigenic syngeneic ultraviolet light-induced tumor. Trypan blue treatment of either donor or recipient decreased the local graft-versus-host reaction. Filtration of lymph node cells from trypan blue-treated donors on a nylon wool column before use in the graft-versus-host assay abrogated the depressive effect of trypan blue. A transient reduction in the blastogenic response of spleen cells to concanavalin A and lipopolysaccharide mitogens was observed after a single injection of trypan blue, but the response of lymph node cells was unaffected. The depressed response of splenic lymphocytes was not entirely reversed by removal of adherent cells. The primary and secondary hemagglutinin responses to sheep erythrocytes were unaffected in trypan blue-treated mice, and the proportion and phagocytic activity of thioglycolate-induced peritoneal macrophages were also unaltered. We conclude that treatment of mice with trypan blue selectively inhibits certain macrophage functions but, at high doses, it can also inhibit some lymphocyte activities.

Agglutinins↗

Effects of trypan blue on cell viability and gene expression in human retinal pigment epithelial cells.

AIM: To evaluate the effects of trypan blue on cell viability and gene expression in human retinal pigment epithelial (RPE) cells. METHODS: Three concentrations (0.06 mg/ml, 0.6 mg/ml, and 4 mg/ml) of trypan blue were applied to human ARPE19 cells for 1 minute. Cell viability was measured using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. RPE cells were sampled daily for 6 consecutive days to assess the effects of trypan blue on cell viability. The effects of trypan blue on the expression of apoptosis related and cell cycle arrest gene expressions including c-fos, c-jun, p53, and p21 were performed using reverse transcription-polymerase chain reaction and immunostaining. RESULTS: The MTT assay showed a concentration dependent suppression effect of trypan blue on cell viability, with higher reduction in the 0.6 mg/ml and 4 mg/ml trypan blue treated groups. No significant change in the expression of c-fos and c-jun was found with all three concentrations of trypan blue. An increase in p53 expression was found in the 4 mg/ml trypan blue treated group at 10-30 minutes after trypan blue application. Immunostaining showed a mild, albeit insignificant, increase of p53 expression in the RPE cells. No significant increase in p21 expression was observed in the 0.06 mg/ml trypan blue treated group but there were significant increases in p21 expression in both the 0.6 mg/ml (p = 0.032) and the 4 mg/ml (p = 0.025) treated groups. CONCLUSIONS: Trypan blue may lead to toxicity on cultured RPE cells as indicated by the reduction in cell viability and changes in the expression of apoptosis related and cell cycle arrest genes at higher concentrations. The application of 0.06 mg/ml trypan blue for 1 minute appeared to have no significant effect on cultured RPE.

Apoptosis↗

Open-sky capsulorrhexis in triple procedure: with or without trypan blue?

PURPOSE: To establish the beneficial effects of trypan blue 0.1% capsule staining in open-sky capsulorrhexis during triple procedure. METHODS: Patients who underwent penetrating keratoplasty (PK) with phacoemulsification and intraocular lens (IOL) implantation were divided into two groups. Group 1 consisted of 31 eyes of 26 patients with a mean age 64.4 +/- 6.9 years and anterior lens capsule was stained with trypan blue 0.1% to perform open-sky capsulorrhexis. In Group 2, capsulorhexis was performed without staining of the anterior capsule in 19 eyes of 17 patients with a mean age 60.6 +/- 5.3 years. The rates of complete capsulorrhexis and intra- and postoperative capsule-related complications were compared between the groups. RESULTS: The most common diagnosis before PK was corneal opacification in both groups. Open-sky capsulorrhexis was not completed in 3 eyes (9.6%) in Group 1 and in 9 eyes (47.3%) in Group 2. The rates of incomplete capsulorrhexis, posterior capsule tear, and transscleral fixation IOL implantation were higher in Group 2 (for each, p < 0.05). The diameters of capsulorrhexis were smaller than 4.5 mm in one eye in Group 1 and in two eyes in Group 2, and larger than 6.5 mm in two eyes in Group 1 and in three eyes in Group 2. Malposition of IOL, zonular dialysis, retinal detachment, and pupil capture were only observed in eyes in Group 2. In the follow-up period, there were no adverse reactions due to application of trypan blue in Group 1. CONCLUSIONS: Trypan blue staining of the anterior capsule during triple procedure helps the surgeon perform open-sky capsulorrhexis more easily and safely and in proper dimensions, provides positive effects on the other steps of the surgery, and decreases the rate of posterior capsule tear formation.

Adult↗

Blockade of P2X-purinoceptors by trypan blue in rat vas deferens.

1. The possibility of an antagonist effect of trypan blue at P2X-purinoceptors was studied in rat vas deferens. 2. Trypan blue (3.2-320 microM) shifted the concentration-contraction response curve of alpha,beta-methylene ATP (alpha,beta-MeATP) to the right and simultaneously increased the maximum of the curve by up to 40%. The Schild plot had a slope not significantly different from unity and yielded a pA2 value of 5.3 (KB 4.9 microM). 3. Suramin (32 microM) also shifted the concentration-response curve of alpha,beta-MeATP to the right, KB 2.6 microM, and increased the maximum by 31%. In the presence of suramin (32 microM), trypan blue (32 microM) did not change the concentration-response curve of alpha,beta-MeATP. 4. 1-Amino-8-naphthol-3, 6-disulphonate (H-acid) 10 mM, the sulphonic acid-carrying moiety of trypan blue, shifted the concentration-response curve of alpha,beta-MeATP to the right, KB 1.4 mM, and increased the maximum by 33%. 5. Trypan blue did not change contractions elicited by high K+ and noradrenaline. 6. Trypan blue attenuated the purinergic component of neurogenic contractions, IC50 44.9 microM, but did not change the adrenergic component. 7. It is concluded that trypan blue blocks P2X-purinoceptors in rat vas deferens. The increase of the maximum of the alpha,beta-MeATP concentration-response curve is similar in mechanism to the increase produced by suramin.

Adenosine Triphosphate↗

Comparative pharmacokinetics of trypan blue in female Sprague-Dawley and Long-Evans rats.

Administration of trypan blue to pregnant Sprague-Dawley or Long-Evans rats, during an identical stage of embryogenesis, has been associated with malformations in 97 and 17% of the offspring, respectively (Gunberg, Anat. Rec. 1958, 130, 310). In the present study the comparative pharmacokinetics of trypan blue in the two strains were investigated. Female Sprague-Dawley and Long-Evans rats were injected sc with 10 mg trypan blue/rat [0.5 ml 2% (w/v) trypan blue in distilled water]. Blood samples were collected from the post-orbital plexus at times ranging from 5 min to 480 hr after dosing. The peak serum concentration of trypan blue was greater in Sprague-Dawley rats. Pharmacokinetic analyses of concentrations of trypan blue in serum resulted in fitting a two-compartment open model, with first order absorption, for both strains. Elimination of trypan blue from the central compartment was faster in Sprague-Dawley rats. This phenomenon was associated with a net movement out of the central compartment, predicted by the ratio of intercompartment rate constants. It is possible that the reported differences between the two strains in the teratogenic effects of trypan blue could be attributable, in part, to these observed pharmacokinetic dissimilarities.

Absorption↗

Trypan blue inhibits complement-mediated phagocytosis by human polymorphonuclear leukocytes.

Trypan blue completely inhibited attachment of human polymorphonuclear leukocytes (PMN) to Sepharose beads coated with C3 ant to sheep erythrocytes coated with IgM plus C3, but it did not inhibit attachment to erythrocytes coated with IgG. These results suggested that trypan blue inhibited C-mediated attachment to PMN membranes. Corroborative studies were performed with a strain of Staphylococcus aureus that requires C but not antibody, for opsonization and that activates the alternative pathway. Trypan blue was not toxic to PMN or bacteria, did nto interfere with immunoglobulin or C interactions, and did not affect attachment of opsonins to bacteria. However, the dye impaired PMN killing of S. aureus in normal nonimmune serum by inhibiting bacterial attachment to and ingestion by PMN. Further evidence that the inhibition was at the C3 receptor level came from the observations that, 1) once staphylococci were attached to PMN at either 37 degrees C or 0 degrees C, addition of trypan blue did not inhibit killing; and 2) trypan blue inhibited killing of bacteria opsonized with serum sufficient in C but previously absorbed at 0 degrees C with the same strain of organism to deplete specific antibody. Further studies with this agent may elucidate the roles of opsonic receptors on human phagocytes.

Cell Adhesion↗

Use of trypan blue for penetrating keratoplasty.

Use of trypan blue for penetrating keratoplasty was developed to facilitate the procedure. Trypan blue is injected before and after the addition of 0.25 mL of an ophthalmic viscosurgical device (OVD), sodium hyaluronate, to stain the internal and external cut edge of the cornea as well as the OVD, enabling the surgeon to improve visualization of the incision and suture depth, improve alignment of host and donor tissues, and ensure that all OVD is removed.

Coloring Agents↗

Some additional observations relating to the mechanism of trypan blue induced teratogenesis.

The mechanism and site of teratogenic action of trypan blue on mammalian embryos was reinvestigated. The experiments to be presented include (1) an analysis of the effect of trypan blue treatment on the morphology of the early mouse egg cylinder, (2) a demonstration of the effect of dye treatment on the enzyme acid phosphatase of yolk sac epithelium using histochemical procedures. Results obtained from these experiments indicate that trypan blue injected into mothers on day 7 of gestational age leads, within 12 to 24 hours after treatment, to dramatic abnormalities in 90-95% of egg cylinders examined. The frequency of gross malformations obtained by this treatment is considerably less when litters are examined at later stages of gestation. Acid phosphatase activity in yolk sac epithelium is depressed by the dye treatment, but there is no difference between enzymatically depressed yolk sacs of malformed embryos and yolk sacs surrounding normally appearing litter mates both obtained from trypan blue treated mothers. The hypothesis that trypan blue may exert its teratogenic effect by the direct exposure of egg cylinder stages to the dye, and that some of the egg cylinders affected may subsequently repair, is recommended for further testing.

Abnormalities, Drug-Induced↗

Identification of retinal breaks using subretinal trypan blue injection.

PURPOSE: To describe the use of subretinal trypan blue to identify retinal breaks during vitrectomy for rhegmatogenous retinal detachment (RD). DESIGN: Interventional case series. PARTICIPANTS: Five patients with RD in whom no retinal break could be identified by internal search with scleral indentation. METHODS: Trypan blue 0.15% was injected transretinally into the subretinal space using a 41-gauge cannula designed for macular translocation surgery. Perfluorocarbon heavy liquid was then injected into the vitreous cavity and the eye was rotated such that trypan blue was vented out of the break. The plume of trypan blue was used to identify retinal breaks, or in some cases staining of the break facilitated break detection. Subretinal fluid was then drained through the break or a drainage retinotomy and surgery was completed using standard techniques. MAIN OUTCOME MEASURE: Identification of previously unseen retinal breaks. RESULTS: This technique successfully identified a retinal break in 4 out of 5 patients. After absorption of the gas tamponade all retinas remained attached with a median visual acuity of 6/12. CONCLUSION: Failure to identify a retinal break during RD surgery is a well-recognized clinical challenge that may adversely affect outcome. In this setting, chromophore-assisted retinal break detection may be a useful surgical technique.

Adolescent↗

Trypan blue: effect on retinal pigment epithelial and neurosensory retinal cells.

PURPOSE: To evaluate the toxicity of trypan blue on retinal cells in vitro. METHODS: Human retinal pigment epithelial cells (ARPE-19) and rat neurosensory retinal cells (R28) were grown in tissue culture and treated with four different concentrations of trypan blue (0.1%, 0.05%, 0.025%, and 0.0125%), in combination with surgical light exposure (0, 5, or 10 minutes). Cell viability, mitochondrial function, and DNA synthesis were measured by trypan blue dye-exclusion assay, mitochondrial dehydrogenase assay, and tritiated [3H] thymidine incorporation, respectively. RESULTS: ARPE-19 and R28 cells exposed to trypan blue with or without illumination did not show any significant decrease, either in cell viability by the dye-exclusion assay or in [3H] thymidine incorporation. R28 cells exposed to 0.1% trypan blue with and without light showed a significant reduction of mitochondrial dehydrogenase activity (P <0.05). ARPE-19 cells exposed to trypan blue, with or without light, did not show any significant decrease in mitochondrial dehydrogenase activity. CONCLUSIONS: This study suggests that rat neurosensory retina (R28) cells are more sensitive than human RPE (ARPE-19) cells to trypan blue. ARPE-19 cells showed no evidence of toxicity with any of the three assays, but R28 cells showed evidence of toxicity with the mitochondrial dehydrogenase assay at the higher doses and light-exposure times studied. Clinical studies must be conducted to determine the safety and efficacy of staining of the inner limiting membrane with trypan blue.

Animals↗