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In ophthalmic drug delivery, a major problem is retaining an adequate concentration of a therapeutic agent in the pre-corneal area. Polycarboxylic acid carriers such as polyaerylic acid and polyitaconic acid in sub-colloidal, nanoparticulate hydrogel form have a strong potential for sustained release of a drug in ocular delivery. Formulations have been prepared of brimonidine loaded in polyearboxylic (polyaerylic and polyitaconic) acid nanopartieles for potential ophthalmic delivery. These particles were prepared by a reverse micro-emulsion polimerization technique with sizes in the range of 50 nm. The loading efficiencies of the drug brimonidine in the particles were shown to be between 80-85% for polyaerylic acid nanoparticles and between 65-70% for polyitaconic nanoparticles. The loading efficiency was also found to be pH dependent. In a preliminary biocompatibility test, human corneal epithelial cells incubated with polyaerylic acid nanopartieles were found to retain their viability, whereas polyitaconic acid nanoparticles were found to be toxic. Two-photon laser scanning microscopic studies of the fluorescently labelled polyacrylic acid nanopartieles and human cornea shows that they are adhesive on the corneal surface. The polyacrylic acid nanoparticles demonstrated a controlled release of the opthalniotofrical drug (Brimonidine) through the human cornea as compared to that of the commercial formulation, AlphaganTM. [ABSTRACT FROM AUTHOR]

Retrobulbar bupivacaine (0.75%) administration has been implicated as a causative factor in respiratory distress, cardiovascular dysfunction, and various central nervous system disturbances. The three cases here demonstrate two separate occurrences of respiratory and central nervous system (CNS) complications following retrobulbar bupivacaine (Marcaine) injection. It is thought that the immediate and delayed occurrences result from inadvertent injection at either of two sites: intravascularly or directly into the membranous sheath surrounding the optic nerve.

A 34-year-old patient, with severe factor VIII deficiency (anti-hemophilic factor deficiency) and inhibitor against factor VIII, underwent a phacoemulsification with posterior capsulatomy and thermal iridectomy under general anesthesia. FEIBA (Factor Eight Inhibitor Bypassing Activity) was used to achieve hemostasis. The surgical procedure was successful and no complication was ensued. A brief management of hemophilia A patient requiring surgery is discussed.