Capsular bag irrigation using 0.025% povidone-iodine in balanced salt solution PLUS for the treatment of postoperative endophthalmitis

Treatment of aggressive posterior retinopathy of prematurity accompanied by nasolacrimal duct obstruction with purulent discharge: A case report

This case demonstrates that probing and 10% povidone-iodine irrigation of the nasolacrimal duct prior to intravitreal bevacizumab injection can safely reduce the risk of endophthalmitis in infants with aggressive posterior retinopathy of prematurity and nasolacrimal duct obstruction. This method provides a viable treatment alternative when laser therapy alone is insufficient.

In praise of povidone-iodine application in ophthalmology

Polyvinyl pyrrolidone or povidone-iodine (PVP-I) is a water-soluble complex formed by the combination of iodine and a water-soluble polymer, polyvinyl pyrrolidone. This complex exerts bactericidal, fungicidal, and virucidal action by gradually releasing free iodine at the site of application to react with pathogens. In ophthalmology, PVP-I is used as a disinfectant and antiseptic agent for preoperative preparation of the skin and mucous membranes and for treating contaminated wounds. PVP-I has been shown to reduce effectively the risk of endophthalmitis in various ocular procedures, including cataract surgery and intravitreal injections; however, it has also been used in the treatment of conjunctivitis, keratitis, and endophthalmitis, with promising results especially in low-resource situations. PVP-I has been associated with complications such as postoperative eye pain, persistent corneal epithelial defects, ocular inflammation, and an attendant risk of keratitis. In cases of poor PVP-I tolerance, applying PVP-I at lower concentrations or using alternative antiseptics such as chlorhexidine should be considered. We provide an update on the efficacy of PVP-I in the prophylaxis and treatment of conjunctivitis, keratitis, and endophthalmitis and a comprehensive analysis of the current literature regarding the use of PVP-I in the management of these ocular conditions. Also, PVP-I-related adverse effects and toxicities and its alternatives are discussed. The goal is to present a thorough evaluation of the available evidence and to offer practical recommendations for clinicians regarding the therapeutic usage of PVP-I in ophthalmology.

Diffuse Corneal Edema after Uneventful Pterygium Surgery: Toxic Anterior Segment Syndrome or Toxic Keratopathy?

A 29-year-old woman was referred to our department for corneal edema after uneventful pterygium excision surgery with conjunctival autografting. She was prescribed topical dexamethasone and showed a complete response within 2 weeks of treatment. Specular microscopic examination revealed severe endothelial cell loss in the operated eye. Mild corneal haze causing a decrease in vision (20/50) was observed in long-term follow-up. This steroid-responsive complication was linked to two possible etiologies: mild toxic anterior segment syndrome or povidone-iodine (PVP-I) corneal toxicity. Surgeons should be careful during pterygium surgery to completely clear PVP-I and avoid any penetration into the anterior chamber to prevent possible serious complications. When diffuse corneal edema is encountered after pterygium surgery, intense steroid treatment should be prescribed as in the present case.

Bacterial Detection Rate and Surgical Outcome in Povidone-Iodine Irrigation After Nasolacrimal Duct Intubation

Purpose

In various ophthalmic surgical procedures, 0.25% povidone-iodine (PI) solution is used to prevent infections. This study examined the bacterial colonisation before and after endoscopic nasolacrimal duct intubation irrigated with PI solution and investigated the relationship between bacterial detection and surgical failure.

Methods

A retrospective study at Saitama Medical University Hospital. We enrolled 113 patients (33 men, 80 women) who underwent lacrimal intubation surgery between April 2016 and December 2018. Preoperatively, the lacrimal pathways were washed with normal saline solution, which was subsequently cultured. The sites of obstruction in the lacrimal pathway were endoscopically determined, perforated, and intubated. The tubes were afterward either irrigated with 0.25% PI or normal saline every 2 weeks. After 8 weeks, a piece of the removed lacrimal tube was cultured. We characterized the pre- and postoperative bacterial cultures.

Results

We enrolled 54 and 52 patients in PI and saline groups (mean age: 69.1±9.2 and 73.2±7.2 years), respectively. In the PI group, Staphylococcus epidermidis was less frequently detected postoperatively than preoperatively. S. oralis and Candida parapsilosis were identified more often postoperatively (P=0.02, P=0.01, respectively). The PI group had significantly lower bacterial detection rate than the saline group (P=0.01). However, the surgical failure rates did not differ between groups. In surgical failure patients, the postoperative rate of Pseudomonas aeruginosa was very high (75%).

Conclusion

PI reduces the bacterial detection rate but does not improve the surgical success rate. P. aeruginosa is associated with an increased risk of surgical failure.

Povidone-iodine concentration and dosing in cataract surgery

Iodine has been recognized as an effective bactericide since the 1800s, and povidone-iodine (PI) solution has been applied to the ocular surface and periocular skin since the 1980s to prevent endophthalmitis in cataract surgery. In vitro, PI solution kills bacteria quickly at dilute concentrations (0.05%-1.0%). In many instances, PI kills bacteria more quickly at these dilute concentrations than more conventional (5%-10%) concentrations. This is due to greater availability of diatomic free iodine in dilute solution, the bactericidal component of PI. The toxicity of PI, both in vitro and clinically, has been shown to be related to concentration. Current American Academy of Ophthalmology and the European Society of Cataract and Refractive Surgeons recommendations regarding PI use suggest using 5% PI before surgery. An alternative dosing strategy uses dilute PI repetitively throughout cataract surgery (0.25% every 30 seconds). We review the povidone-iodine literature with attention to basic science and use of dilute PI.