The effect of timolol maleate (0.5%) on tonic accommodation and tonic vergence

Blue rubber bleb nevus syndrome (BRBNS) is a rare syndrome characterized by venous malformations of mostly skin and gastrointestinal tract. Patients present with multiple venous malformations in various organs including liver, spleen, heart, eye, and central nervous system. Few ophthalmological cases have been published in literature and at present, there are no clear guidelines on the treatment of eye hemorrhages associated with the BRBNS. We report a 3-year-old boy with the BRBNS who developed a spontaneous progressive enlarging subconjunctival hemorrhage in the left eye despite being treated with oral propranolol. The subconjunctival hemorrhage was caused by an underlying conjunctival vascular malformation. With topical treatment with timolol maleate 0.5% once a day in the affected eye, the lesion regressed completely after 4 months. This child represents the first case of the BRBNS associated with a subconjunctival progressive bleeding necessitating topical treatment despite oral propranolol effectively controlling the cutaneous lesions. We recommend ophthalmic screening of patients with BRBNS in early childhood. For patients with BRBNS-related subconjunctival vascular lesions with subsequent hemorrhage, treatment with a topical β-blocker may be an efficient and harmless treatment option.

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The Use of an Opacitometer to Compare the In Vitro Cornea Opacifying Effects of Timolol With and Without Benzalkonium Chloride

Alternatives to Laboratory Animals ◽

10.1177/026119299101900220 ◽

1991 ◽

Vol 19 (2) ◽

pp. 263-270

Author(s):

Haruyoshi Igarashi ◽

Yasunaga Katsuta ◽

Yoshiharu Nakazato ◽

Tohru Kawasaki

Keyword(s):

Benzalkonium Chloride ◽

Additive Effects ◽

Timolol Maleate ◽

Epithelial Surface ◽

Endothelial Surface ◽

Draize Test ◽

Corneal Opacities

We have evaluated a new in vitro opacitometer method as an alternative to the in vivo Draize test for ocular irritancy. Several concentrations of timolol maleate (timolol) with or without 0.005% benzalkonium chloride were applied to porcine isolated corneas which were either intact or with the epithelium, endothelium, or both epithelium and endothelium removed. Corneal opacities were measured using an opacitometer. In general, timolol with benzalkonium chloride caused a greater degree of opacity to develop in the cornea than did timolol alone. At the lower concentrations of timolol, the increased opacity probably represented additive effects of the two compounds. However, at the highest concentration of timolol (5 x 10 2M), there was an enhanced opacification in the presence of benzalkonium chloride, which may have been due to an increase in penetration, particularly through the epithelium. Timolol caused a greater degree of opacity to develop in the isolated intact porcine corneas when the drug was applied to the endothelial surface, than when applied to the epithelial surface or to both the epithelial and endothelial surfaces. However, timolol with benzalkonium chloride caused a greater degree of opacity in the intact cornea, when the drug was applied to both surfaces than when it was applied only to the epithelial or the endothelial surface.

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FORMULATION AND CHARACTERIZATION OF TIMOLOL MALEATE-LOADED NANOPARTICLES GEL BY IONIC GELATION METHOD USING CHITOSAN AND SODIUM ALGINATE

International Journal of Applied Pharmaceutics ◽

10.22159/ijap.2019v11i6.34983 ◽

2019 ◽

pp. 48-54 ◽

Cited By ~ 1

Author(s):

RISA AHDYANI ◽

LARAS NOVITASARI ◽

RONNY MARTIEN

Keyword(s):

Particle Size ◽

Zeta Potential ◽

Sodium Alginate ◽

Release Kinetics ◽

In Vitro Release ◽

Entrapment Efficiency ◽

Polydispersity Index ◽

Ionic Gelation ◽

Timolol Maleate ◽

Optimum Formula

Objective: The objectives of this study were to formulate and characterize nanoparticles gel of timolol maleate (TM) by ionic gelation method using chitosan (CS) and sodium alginate (SA). Methods: Optimization was carried out by factorial design using Design Expert®10.0.1 software to obtain the concentration of CS, SA, and calcium chloride (CaCl2) to produce the optimum formula of TM nanoparticles. The optimum formula was characterized for particle size, polydispersity index, entrapment efficiency, Zeta potential, and molecular structure. Hydroxy Propyl Methyl Cellulose (HPMC) K15 was incorporated into optimum formula to form nanoparticles gel of TM and carried out in vivo release study using the Franz Diffusion Cell. Results: TM nanoparticles was successfully prepared with concentration of CS, SA, and CaCl2 of 0.01 % (w/v), 0.1 % (w/v), and 0.25 % (w/v), respectively. The particle size, polydispersity index, entrapment efficiency, and Zeta potential were found to be 200.47±4.20 nm, 0.27±0.0154, 35.23±4.55 %, and-5.68±1.80 mV, respectively. The result of FTIR spectra indicated TM-loaded in the nanoparticles system. In vitro release profile of TM-loaded nanoparticles gel showed controlled release and the Korsmeyer-Peppas model was found to be the best fit for drug release kinetics. Conclusion: TM-loaded CS/SA nanoparticles gel was successfully prepared and could be considered as a promising candidate for controlled TM delivery of infantile hemangioma treatment.

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