Dose and administration of intracameral moxifloxacin for prophylaxis of postoperative endophthalmitis.

PURPOSE: To review current and past practices of intracameral antibiotic administration for infection prophylaxis in cataract surgery; to review the benefits and liabilities of available prophylactic drugs, dosage determination, and administration protocols; and to devise an optimum dose and administration protocol for intracameral moxifloxacin. SETTING: Humber River Hospital and the University of Toronto, Toronto, Ontario, Canada. DESIGN: Retrospective evaluation of treatment modality. METHODS: This study consisted of a detailed review of the history, drugs, and methods of intracameral prophylaxis and microbiological and pharmacodynamics analysis of options. A review of potential drug sources and doses was performed and 1 drug, dose, and administration protocol was selected. The current method's adoption reasons are described followed by the authors' experience. RESULTS: A single infection in 3430 cases occurred with a moxifloxacin-resistant strain of Staphylococcus epidermidis when moxifloxacin 100 mcg in 0.1 mL was used. Increasing the dose and changing the administration technique resulted in no infections in 4601 cases and no detrimental side effects or complications. CONCLUSION: Intracameral moxifloxacin prepared by dilution of 3 cc moxifloxacin 0.5% (Vigamox) with 7 cc balanced salt solution and with the administration of 0.3 to 0.4 cc (450 to 600 mcg.) as the final step in cataract surgery via the side port after the main incision has been sealed and hydrated showed advantages over alternative intracameral antibiotic prophylactic methods, with minimum risk. FINANCIAL DISCLOSURE: Neither author has a financial or proprietary interest in any material or method mentioned.

Tri-soft shell technique.

Soft-shell techniques exist for lower viscosity dispersive with higher viscosity cohesive ophthalmic viscosurgical devices (OVDs) (soft-shell technique [SST]), viscoadaptive OVDs with balanced salt solution (ultimate soft-shell technique), intraoperative floppy-iris syndrome (soft-shell bridge), and many specific modifications for disinserted zonular fibers, frayed iris strands, Fuchs endothelial dystrophy, small holes in the posterior capsule with protruding vitreous, capsular dye use, and others. Soft-shell techniques exist because it is rheologically impossible to control the surgical environment with a single OVD as well as with an ordered combination of rheologically different OVDs. Surgeons frequently confuse these techniques because of their multitude. This paper unifies all SSTs into a single improved tri-soft shell technique (TSST), from which basic specific applications to unusual circumstances are simple and intuitive. As shown with previous SSTs, the TSST allows surgeons to perform complex tasks with greater surgical facility and to protect endothelial cells better than with single OVDs.

Perspectives on antibiotics for postoperative endophthalmitis prophylaxis: potential role of moxifloxacin.

To aid the cataract surgeon's understanding of rational approaches to antimicrobial prophylaxis and place the European Society of Cataract & Refractive Surgeons (ESCRS) postoperative endophthalmitis study in perspective, a review was conducted of published and unpublished data on intracameral antibiotic use during cataract surgery and the antimicrobial efficacy, pharmacodynamics, ocular penetration, and safety of moxifloxacin. The ESCRS-sponsored study of postoperative endophthalmitis prophylaxis reported rates of presumed infectious postoperative endophthalmitis of 0.07% with intracameral cefuroxime treatment and 0.34% in control groups. Postoperative endophthalmitis after cefuroxime use was mostly due to cefuroxime-resistant gram-positive bacteria. Intracameral cefuroxime also requires extemporaneous compounding, has short-term stability, and carries a risk for hypersensitivity. Moxifloxacin, a fourth-generation fluoroquinolone, has potent and rapid bactericidal activity against the most common gram-positive postoperative endophthalmitis pathogens, has excellent ocular penetration after topical administration, and is available in a self-preserved ophthalmic formulation that has been shown safe and effective in preventing endophthalmitis when administered intracamerally in an animal model. Available data suggest that the optimum antibiotic regimen and route of delivery for cataract surgery antimicrobial prophylaxis require further study. Moxifloxacin offers many theoretical advantages that make it an attractive first-line choice for topical use and of interest for intracameral administration.

Effect of retrobulbar injection of lidocaine on saccadic velocities.

PURPOSE: To determine whether exposing the extraocular muscles (EOMs) to lidocaine via retrobulbar injection for cataract surgery has a demonstrable negative effect on subsequent function of the muscle. SETTING: York Finch Eye Associates, Humber River Regional Hospital, and Toronto Western Hospital Research Institute, Toronto, Ontario, Canada. METHODS: This study comprised 37 eyes that had phacoemulsification and posterior chamber intraocular lens implantation; 13 eyes had retrobulbar lidocaine with hyaluronidase and 24 eyes, topical anesthesia. The postoperative saccadic velocities were compared with the preoperative velocities using a sensitive recording device. The results were compared within and between the retrobulbar lidocaine and topical anesthesia groups. RESULTS: No detectable decrement in postoperative saccadic velocities was detected in any patient, and no difference was found between the groups. CONCLUSIONS: Exposing EOMs to lidocaine for cataract surgery had no detectable negative effect on saccadic velocities 1 week after surgery.