Experimental evaluation of aniline and methyl blue for intraocular surgery.
OBJECTIVE
The purpose of this study was to investigate the biocompatibility of aniline and methyl blue in a well-established cell culture model and assess the staining properties of these dyes at the level of the internal limiting membrane (ILM) in human donor eyes.


METHODS
Dye-related toxicity was evaluated by a colorimetric test (MTT) measuring the inhibition of retinal pigment epithelium (ARPE-19 and primary human retinal pigment epithelium) cell proliferation. Cell viability was also quantified based on a two-color fluorescence assay (Life-Dead Assay). Aniline blue and methyl blue at a concentration of 0.2% was applied over the macula during vitrectomy in human donor eyes to evaluate the staining properties at the level of the ILM.


RESULTS
Both dyes and dye concentrations of 0.1% and 0.2% showed no toxic effect on ARPE-19 and primary human retinal pigment epithelium cell proliferation for exposure times of 1 and 10 minutes, respectively. Cell viability was also not affected at all. Both dyes provided a good contrast at the level of the ILM and allowed for a controlled removal of the ILM during surgery. No penetration into deeper retinal layers was noted.


CONCLUSIONS
Our results indicate that aniline blue and methyl blue might be applicable for intraocular surgery, providing a very good biocompatibility and required selective staining characteristics at the level of the ILM.
Haritoglou
Christos
C
Department of Ophthalmology, Ludwig-Maximilians-University, Munich, Germany. christos.haritoglou@med.unimuenchen.de
Priglinger
Siegfried
S
Liegl
Raffael
R
May
Christian A
CA
Eibl
Kirsten
K
Thaler
Sebastian
S
Kampik
Anselm
A
Schuettauf
Frank
F
D000328:Adult; D000368:Aged; D000814:Aniline Compounds / Q000633:toxicity*; D001485:Basement Membrane; D001557:Benzenesulfonates / Q000633:toxicity*; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D004396:Coloring Agents / Q000633:toxicity*; D005456:Fluorescent Dyes / Q000633:toxicity*; D006801:Humans; D008875:Middle Aged; D012164:Retinal Diseases / Q000601:surgery; D055213:Retinal Pigment Epithelium / Q000187:drug effects*
D000814:Aniline Compounds; D001557:Benzenesulfonates; D004396:Coloring Agents; D005456:Fluorescent Dyes; C017006:aniline blue; C414357:Methyl Blue