Use of Intracameral Moxifloxacin for the Prevention of Acute Endophthalmitis Following Cataract Surgery: a Controlled and Randomized Clinical Trial

Patients who are diagnosed with cataracts and for whom surgery is indicated shall be evaluated in terms of their visual acuity and refractive error and via biomicroscopy, automated keratometry (Auto Kerato Refractometer KR 8000® Alcon), Goldmann applanation tonometry, fundoscopy, biometric assessment (Ocuscan RxP® Alcon or Lenstar LS900® Haag-Streit International), and specular microscopy of the cornea (EM-3000® Tomey) to count the corneal endothelial cells. Each cataract case shall be classified based on the Lens Opacities Classification System III (LOCS III).

Patients who choose to sign the informed consent form after being informed of all of the aspects of the surgery and this trial shall be randomly divided into 2 groups that shall be approximately equal in size and stratified by gender. Group A shall receive an intracameral injection of 0.03ml of 0.5% moxifloxacin (150 micrograms in 0.03 ml) at the end of the cataract surgery, followed by the use of a 0.5% moxifloxacin in eye drop form associated with 0.1% dexamethasone before the bandage is applied. Group B shall not receive the intracameral moxifloxacin injection at the end of the cataract surgery; these patients shall receive only 0.5% moxifloxacin in eye drop form associated with 0.1% dexamethasone before the bandage is applied.

The cataract surgery shall be performed using the standards followed by the Department of Ophthalmology at São Paulo State University, Campinas (UNICAMP). It shall be performed by second-, third-, and fourth-year ophthalmology residents and by attendings when cases are more complex. Preoperative pupil dilation shall be performed through the use of 10% phenylephrine and 1% tropicamide 3 times in five-minute increments. The anesthesiology technique used shall depend on each case and shall be either topical anesthesia, peribulbar anesthesia, sub-Tenon anesthesia, or general anesthesia. Skin sterilization shall be performed using an aqueous solution of 10% povidone-iodine. After the sterile surgical field is established and the eyelashes are isolated, 4 eye drops containing 5% povidone-iodine shall be administered in the conjunctival sac with subsequent irrigation using a 10% balanced salt solution. In cases of allergy to povidone-iodine, an aqueous solution of 0.05% chlorhexidine shall be used. The principal incision (using a clear corneal incision or the near clear approach) shall be 2.2mm to 3.0mm in length. The phacoemulsification technique shall be either the stop and chop, the phaco chop, the pre-slice, the pre-chop, or the divide and conquer; it shall be applied through the use of the Infiniti® or the Laureate® phacoemulsifier (Alcon), with an AcrySof® intraocular foldable lens (Alcon). In cases of posterior capsule rupture and vitreous loss, a complication that increases the chance of endophthalmitis,3,4,15 a mechanical or manual anterior vitrectomy shall be performed (the choice shall depend on the case). In cases of thermal burn of the principal incision or other situations in which surgical injury is not self-sealing and in which there is a consequent leak of the aqueous humor and an inability to keep the anterior chamber in adequate dimensions, the incision shall be sutured using Mononylon 10.0.

The moxifloxacin injection shall be prepared by a trained nurse or physician: 0.03ml (150 micrograms) of 0.5% moxifloxacin as an ophthalmic solution (Vigamox®) shall be aspirated. The eye drop bottles shall be opened at the moment of preparation with a 0.3ml coupled syringe (Terumo®) through the use of an asseptic technique. The solution shall then be injected into the anterior chamber via paracentesis as the last step in the phacoemulsification surgery. The patients from the two groups shall receive 0.5% moxifloxacin drops associated with 0.1% dexamethasone after the surgery is completed and before the bandage is applied. The postoperative prescription shall consist of 0.5% moxifloxacin associated with 0.1% dexamethasone. Administration shall begin 3 hours after the surgery is completed and should continue every 3 hours for 7 days (except when the patient is sleeping). After the 7th postoperative day, 0.1% dexamethasone without association with moxifloxacin shall be prescribed. Its application shall be gradually reduced over the course of 3 weeks according to each individual's inflammatory response.

Patients from both groups shall be masked, while the surgeons and ophthalmologists who perform the postoperative examinations will not. In suspected cases of endophthalmitis, an independent ophthalmologist from a retina and vitreous practice shall perform the patient's examination without knowing whether the patient belongs to Group A or Group B. This independent ophthalmologist shall then recommend the most adequate course of action. Endophthalmitis treatment shall follow the usual protocol. The postoperative consults shall be held on the 1st, 7th, 30th, and 45th postoperative days and shall include evaluations of visual acuity (7th, 30th, and 45th postoperative day), refractive error (30th postoperative day), biomicroscopy (1st, 7th, 30th, and 45th postoperative day), applanation tonometry (7th, 30th, and 45th postoperative day), keratometry (30th postoperative day), fundoscopy (30th, and 45th post operative day), and endothelial cell counts (45th postoperative day).