Cornea - ARVO

ARVO 2013 Annual Meeting Abstracts by Scientific Section/Group - CorneaFig. 1. Comparison between fluorescence intensity and NaFconcentration from a 5-ìm thick film (filled diamonds) and theory(line). Colors corresponding to intensity values are also shown.of SIRC cell cultures treated with BAK, pure and mixed with HA,was examined.Results: Pure BAK instantaneously inserted in the lipid films(corneal or meibomian). The interaction resulted in impairedspreading and discontinuous patchy structure of the lipid films,increased surface pressure-area hysteresis and partial displacement ofthe lipids by BAK from the surface. The inclusion of HA in the filmssubphase opposed to these adverse effects and at ≥ 0.1% HA theproperties of the lipid films were maintained for the entire BAKconcentration range. Identical results were obtained with cell cultureexperiments which showed that SIRC cells maintained high viabilityat ≥ 0.1% HA.Conclusions: HA at concentration ≥ 0.1% HA was able to efficientlysuppress the adverse effects of BAK on the properties of meibomianand corneal lipid films and on the viability of SIRC cells. Thusmixtures of BAK and HA represent prospective compositions foreyedrop formulations. Surface chemistry based approach is proposedfor in vitro molecular scale characterization of pharmaceuticallyapplicable polymers and their interactions with tear film lipids.Commercial Relationships: Georgi A. Georgiev, RohtoPharmaceuticals (F), Santen (F), Menicon (F); Norihiko Yokoi,Santen Pharmaceutical (F), Otsuka Pharmaceutical (F), Kowa (P),Kissei Pharmaceutical (C), Menicon (F), Alcon Japan (F), Whitemedical (F), Nitten (F), Rohto (C), Nidek (F), Johson & Johnson (F);Slavyana Ivanova, None; Rumen Krastev, None; ZdravkoLalchev, NoneSupport: The research is funded by Santen Pharmaceutical.Fig 2. Predicted dynamic of color change for black-spot formation.Commercial Relationships: CHENG-CHUN PENG, None; BoTan, None; Meng C. Lin, TearLab Corporation (F), Allergan, Inc.(F); Clayton J. Radke, novartis corporation (F)Program Number: 944 Poster Board Number: B0249Presentation Time: 1:00 PM - 2:45 PMSurface Chemistry Study Of The Interactions Of BenzalkoniumChloride and Hyaluronic Acid With Meibomian And CornealLipidsGeorgi A. Georgiev 1 , Norihiko Yokoi 2 , Slavyana Ivanova 1 , RumenKrastev 3 , Zdravko Lalchev 1 . 1 Biochemistry, Sofia University "StKliment Ohridski", Sofia, Bulgaria; 2 Ophthalmology, KyotoPrefectural University of Medicine, Kyoto, Japan; 3 Biomaterials,NMI Naturwissenschaftliches und Medizinisches Institut an derUniversität Tübingen, Reutlingen, Germany.Purpose: Dodecyl dimethyl benzyl ammonium chloride (BAK) iscommonly used preservative in eyedrop formulations, known toimpair the integrity of the tear film lipid layer and of the cornealepithelium membranes. We studied the capability of high molecularweight (Mw 1x10+6) hyaluronic acid (HA; Santen Pharmaceutical,Osaka, Japan) to protect meibomian and corneal lipid films at theair/water interface from the adverse action of BAK.Methods: Human meibum was collected from healthy volunteers;corneal lipids were extracted from SIRC cell culture. The interactionsof BAK with meibomian and corneal lipids at the air/water interfacein presence and absence of HA in the film subphase were examinedin vitro at blink-like compression/expansion of film area byLangmuir surface balance. The sample’s lateral elasticity andcapability to compress and spread during dynamic area changes wereevaluated through the surface pressure-area isotherms and isocycles.The lipid films morphology was monitored by Brewster AngleMicroscopy. BAK concentration was kept within the clinical range of0.005-0.02%; HA was used in the range of 0.01-0.3%. The viabilityProgram Number: 945 Poster Board Number: B0250Presentation Time: 1:00 PM - 2:45 PMEfficacy of rebamipide for laser in situ keratomileusis-associateddry eyeYosai Mori, Ryohei Nejima, Ayami Masuda, Yoko Maruyama,Keiichiro Minami, Kazunori Miyata. Miyata Eye Hospital,Miyakonojo, Japan.Purpose: Dry eye syndrome is a major complication after laser insitu keratomileusis (LASIK), and is occasionally hard to improvewith an artificial tear or hyaluronic acid treatment. Rebamipide is aquinolinone derivative stimulating mucin secretion as well asincreasing goblet cells on the conjunctiva, resulting in improvementof ocular surface disorders. Aim of the study is to evaluate theefficacy of rebamipide for dry eye after LASIK.Methods: This prospective study comprised 32 eyes of 16 patientswho had LASIK-associated dry eye and had been treated with theartificial tear or hyaluronic acid eye drop. Rebamipide 2% eyedrop(Mucosta, Ohtsuka Pharmaceutical) was additionally instilled 4 timesa day for 4 weeks. Tear secretin was examined with the Schirmer testwith anesthesia before and at 4 weeks after the rebamipide treatment.Tear breakup time (BUT), fluorescein stain, and lissamine green stainwere examined before and at 1 and 4 weeks. Fluorescein staining onthe cornea was evaluated by the summation of area and densityscores (none:0 to severe:3). Lissamine green staining in theconjunctiva was scored in none:0 to full:18. Questionnaire of 14symptoms according to Ocular Surface Disease Index was performedbefore and at 4 weeks. Change in the examinations after theadditional treatment was evaluated with the Friedman's test followingScheffe ad-hoc comparison. Symptoms were compared with theWilcoxon signed-ranks test.Results: Mean tear secretin did not change beween beforerebamipide treatment (8.8 mm) and after 4 weeks (8.2 mm). BUTsignificantly increased from before (3.4 sec.) to 1 week (4.8 sec.,P