Povidone-iodine concentration and dosing in cataract surgery

Surgical site antiseptic preparations for otolaryngology - Head and neck surgery: A current review

OBJECTIVE

To review current literature and guidelines on antiseptic surgical site preparations for preventing surgical site infections with consideration of contraindications specific to head and neck surgery.

DATA SOURCES

PubMed/MEDLINE, clinicaltrials.gov, accessdata.fda.gov, Manufacturer websites.

REVIEW METHODS

A scoping review on the literature and clinical studies comparing the efficacy of different surgical site preparations. Studies were included if they were a randomized controlled trial (RCT) comparing at least two commonly used and available antiseptic preparations. Additionally, a compilation of warnings and contraindications from manufacturer labels and articles are included. Due to the lack of randomized controlled trials concerning antiseptic preparation use in head and neck surgery specifically, an additional search was executed for articles not limited to randomized controlled trials that compared different antiseptic preparation used in surgeries concerning the head and neck.

RESULTS

Of 56,983 resulting abstracts and 3798 of them being screened, 25 RCTs were included. These RCTs included a variety of surgeries including gastrointestinal, obstetric, gynecologic, orthopedic, and vascular procedures. When searching for abstracts concerning head and neck surgeries, 9 studies were found and included.

CONCLUSIONS

To reduce surgical site infections and avoid application in situations with contraindications, practicing surgeons need to be familiar with the existing literature regarding different surgical preparations and what warnings manufacturers have listed on the products. Optimal surgical site preparation for head and neck surgery is challenging as proximity to oxygen contraindicates newer alcohol-based options that are potentially flammable. We summarize evidence-based surgical site preparation for head and neck surgery.

Prophylactic Intracameral Antibiotics and Endophthalmitis After Cataract Surgery

Importance

Although the effectiveness of intracameral antibiotics to prevent postoperative endophthalmitis is described, selective use of antibiotics combined with 1% povidone iodine disinfection might be equally effective and could lead to cost reduction and avoidance of unnecessary use of antibiotics.

Objective

To compare the incidence of postoperative endophthalmitis when 1% povidone iodine disinfection is applied in combination with selective intracameral antibiotics with the incidence after routine use of intracameral antibiotics in combination with 5% povidone iodine.

Design, Setting, and Participant

This was a retrospective cohort study using incidence data from the ongoing endophthalmitis register of the Rotterdam Eye Hospital, a specialized hospital providing both secondary and tertiary ophthalmological care, when intracameral antibiotics were used only during cataract procedures with occurrence of a posterior capsular tear in comparison with results from cohorts described in the literature where routine antibiotics were used. All patients who had cataract (phacoemulsification) surgery at the Rotterdam Eye Hospital between 1993 and 2022 were included. No cataract surgical procedures combined with other intraocular procedures were included.

Exposure

Povidone iodine disinfection and intracameral antibiotics during cataract surgery either routinely or only in case of posterior capsular tears.

Main Outcome and Measure

Postoperative endophthalmitis incidence.

Results

Postoperative endophthalmitis incidence after 56 598 cataract (phacoemulsification) surgical procedures in the Rotterdam Eye Hospital between 2016 and 2022 was 0.000 (95% CI, 0.000-0.000). A PubMed literature search until September 2023 with respect to the incidence of postoperative endophthalmitis after routine antibiotic prophylaxis yielded 37 publications with an overall postoperative endophthalmitis incidence of 0.000 (95% CI, 0.000-0.000).

Conclusions and Relevance

No difference was observed between the postoperative endophthalmitis incidence during the last 7 years in the Rotterdam Eye Hospital and the overall postoperative endophthalmitis incidence after routine intracameral antibiotics prophylaxis as described in the literature. Disinfection with 1% povidone iodine in combination with selective antibiotic prophylaxis may be equally effective as routine antibiotic use and 5% povidone iodine.

Evaluation of the Possible Influence of Povidone Iodine (PVI) Solution and Polyhexanide (PHMB) on Wound Healing in Corneal Epithelial Regeneration

This study investigates the possible toxic effects of the preoperative antiseptic substances povidone iodine (PVI) and polyhexanide (PHMB; Serasept® 2) on wound healing in ophthalmology. To assess this impact, human telomerase-immortalized corneal epithelial (hTCEpi) cells and human telomerase-immortalized conjunctival epithelial (hCjE) cells were exposed to 1% and 5% PVI or 0.04% PHMB for different periods to evaluate the cytotoxicity of these two antiseptics. Furthermore, the toxicity of these antiseptics was investigated in a human tissue-specific corneal epithelial construct and porcine eye culture model. The results reveal the high cytotoxicity of PVI and PHMB in the hTCEpi and hCjE in monolayer cell culture models, independent of the incubation time and concentration of these substances. However, after hTCEpi cell differentiation into a tissue-specific corneal epithelial construct, contact with these antiseptics for the relevant preoperative time did not alter cPARP1 or Ki67 expression. Furthermore, the wound-healing process in the porcine cornea was not significantly influenced after incubation with these antiseptics. In summary, corneal and conjunctival epithelial cell lines are very sensitive to PVI and PHMB, whereas no significant alterations were found in intact tissue-specific corneal epithelial constructs or porcine corneas. Therefore, we could not identify PVI and PHMB as reasons for postoperative eye irritation.

Long-Term Real-World Outcomes of Corneal Changes in Proliferative Diabetic Retinopathy: Panretinal Photocoagulation vs. Intravitreal Conbercept

PURPOSE

To compare long-term real-world outcomes of corneal thickness (CT) alterations in proliferative diabetic retinopathy (PDR) patients treated with panretinal photocoagulation (PRP) and intravitreal conbercept (IVC).

METHODS

This retrospective study included 69 eyes of 69 patients with PDR (42 PRP and 27 IVC). Full corneal thickness (FCT), corneal epithelial thickness (CET) and corneal stromal thickness (CST) measured by anterior segment optical coherence tomography at baseline were compared between groups. These CT changes at last follow-up from baseline were also compared between groups and within each group.

RESULTS

During a mean follow-up of more than two years, the IVC group demonstrated a significantly increased corneal thickness from baseline compared to the PRP group in some areas (PRP vs. IVC: FCT 0-2 mm: -0.59 ± 9.31 vs. 5.59 ± 9.23 μm, p = 0.009; CST 0-2 mm: -2.05 ± 8.79 vs. 3.48 ± 7.52 μm, p = 0.015; CST 2-5 mm: -1.78 ± 13.27 vs. 5.68 ± 14.53 μm, p = 0.046). In within-group comparisons, a significantly increased FCT from baseline was found in the 0-2 mm area in the IVC group (p = 0.004), but no significant change was observed in the PRP group (p = 0.691). For CET changes, a significantly increased CT was observed in the 0-2 mm, 2-5 mm and 5-7 mm areas in both groups respectively (all p < 0.05). Regarding CST, an increased CT was found in the 0-2 mm area in the IVC group (p = 0.037), while a decreased trend was observed in 0-2 mm and 2-5 mm areas in the PRP group (all p > 0.05).

CONCLUSION

When using PRP or IVC in the long-term management of PDR, CT changes should be considered. This may provide evidence for corneal protection during PDR treatment.

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.

A survey of Asian Eye Institutions on perioperative antibiotic prophylaxis in cataract surgery

PURPOSE

To determine current institutional practice patterns for the use of perioperative antibiotics and other measures to prevent infection after cataract surgery in Asia.

METHODS

An online survey-based study of leading eye institutions in China, Hong Kong, India, Indonesia, Japan, Malaysia, Pakistan, Philippines, Singapore, South Korea, Taiwan, Thailand and Vietnam was conducted. The survey was administered to 26 representative key opinion leaders from prominent tertiary eye institutions that are also national academic teaching institutions in Asia. Survey responses were collated and anonymized during analysis.

RESULTS

All surveyed institutions used povidone iodine for the preoperative antiseptic preparation of the eye, with notable variations in the concentration of povidone iodine used for conjunctival sac instillation. Preoperative topical antibiotics were prescribed by 61.5% and 69.2% of institutions in low-risk and high-risk cases, respectively. Regarding the use of intra-operative antibiotics, 60.0% and 66.7% of institutions administered intracameral antibiotics in low-risk and high-risk patients, respectively. Postoperative topical antibiotics use patterns were generally very similar in low-risk and high-risk patients. Over half of the institutions (52.2% and 68.0% in low-risk and high-risk patients, respectively) also indicated prolonged postoperative use of topical antibiotics (> 2 weeks). Not all surveyed institutions had established policies/protocols for perioperative antibiotic use in cataract surgery, endophthalmitis surveillance, and/or a monitoring program for emerging antimicrobial resistance.

CONCLUSION

There are variations in antimicrobial prophylaxis approaches to preoperative, intra-operative and postoperative regimens in cataract surgery in Asia. More evidence-based research is needed to support the development of detailed guidelines for perioperative antibiotic prophylaxis to reduce postoperative infections.

Calix[4]arene Derivative for Iodine Capture and Effect on Leaching of Iodine through Packaging

A hydrophobic calix[4]arene derivative was investigated for its iodine (I₂) capture efficiency from gaseous and liquid phase. The iodine uptake was followed by UV-vis spectroscopy. Additionally, the influence of the calix[4]arene derivative-polyolefin system on the leaching of iodine through packaging from a povidone-iodine-based (PVP-I) formulation was evaluated. In fact, iodine is a low-cost, multi-target, and broad-spectrum antiseptic. However, it is volatile, and the extended storage of I₂-based formulations is challenging in plastic packaging. Here, we investigated the possibility of reducing the loss of I₂ from an iodophor formulation by incorporating 4-tert-butylcalix [4]arene-tetraacetic acid tetraethyl ester (CX) and its iodine complex in high-density polyethylene (HDPE) or polypropylene (PP) via a swelling procedure. Surface and bulk changes were monitored by contact angle, thermogravimetric analysis (TGA), and UV-vis diffuse reflectance spectra. The barrier effect of the different polymeric systems (embedded with CX, iodine-CX complex, or I2) was evaluated by monitoring the I2 retention in a buffered PVP-I solution by UV-vis spectroscopy. Overall, experimental data showed the capability of the calix[4]arene derivative to complex iodine in solution and the solid state and a significant reduction in the iodine leaching by the PP-CX systems.

Povidone-Iodine Adverse Effects and Alternatives for Ocular Procedures

Purpose: Povidone-iodine (PVI), also known as Betadine, is a widely used antiseptic agent used in several fields of medicine. In ophthalmology, it is applied as a preoperative antiseptic to prevent infectious complications that can result from surgical procedures. PVI's safety and efficacy have been extensively studied and represented in the literature; however, the incidence of adverse effects has been reported in conjunction. The aim of this paper is to compile information regarding PVIs use, safety profile, adverse effects, and possible alternatives through a review of the existing literature. Methods: Literature was compiled utilizing the database PubMed and Google Scholar using specified keywords with a total of 86 reviewed articles, after excluding search results that did not meet the inclusion criteria. Results: While the allergic potential to PVI is a highly contested topic, there are several nonallergic adverse effects of PVI that should not be overlooked. These effects include chemical burn, cytotoxic effects, and general patient discomfort. In light of these adverse effects, alternatives to PVI may be considered. However, there has been little research identifying feasible alternatives in preoperative intraocular procedures. Alternatives including chlorhexidine, polyhexamethylene biguanide (polyhexanide), and octenidine were identified as potential substitutes for PVI. Conclusions: Further study is needed to provide robust evidence regarding the efficacy profiles of these alternatives in comparison with PVI and to demonstrate comparable tolerance to PVI in intraocular procedures.

Are Prophylactic Systemic Antibiotics Required in Patients with Cataract Surgery at Local Anesthesia?

The reduced use of antimicrobial drugs has been recommended worldwide, according to the global action for antimicrobial resistance published in 2015 by the World Health Organization. In this study, we retrospectively reviewed the incidence of surgical site infection in consecutive patients with cataract surgeries at a single hospital in the 6-year process when prophylactic systemic antibiotics were reduced in a step-by-step manner. The entire study period from 2016 to 2022 was divided into five stages, based on the use of systemic antibiotics. In stage 1 with 649 cataract surgeries, an intravenous drip infusion of cefazolin 1 g was given at surgery, followed by oral cefdinir 100 mg in the evening on surgery day and three times for two postoperative days. In stage 2 with 541 cataract surgeries, oral cefdinir 100 mg was given in the late morning before surgery, in the evening, and three times (300 mg in total) for two postoperative days. In stage 3 with 103 cataract surgeries, oral levofloxacin 500 mg was given in the late morning before surgery and once in the morning for two postoperative days. In stage 4 with 545 cataract surgeries, oral levofloxacin 500 mg was given only in the late morning before surgery. In stage 5 with 311 cataract surgeries, no systemic antibiotics were given. As common procedures in all stages, moxifloxacin eye drops were given four times daily as topical antibiotics in the 3 days before surgery and about 2 weeks after surgery. At surgery, the ocular surface was frequently irrigated with saline-diluted povidone iodine at 0.5% working concentration. No postoperative infection was recorded in any stage. This study showed neither harm nor risk in reduced use and, consequently, no use of prophylactic systemic antibiotics in cataract surgery as far as local precautionary measures were secured.

Evaluation of the effect of gentamicin in surgical perfusion solution on cataract postoperative endophthalmitis

Objective

To evaluate the effect of gentamicin in surgical perfusion solution on endophthalmitis incidence after cataract surgery.

Methods

A retrospective analysis of endophthalmitis incidence was conducted in two groups of patients who underwent cataract surgery, with (Group B) or without gentamicin (Group A) in the surgical perfusion solution. Endophthalmitis incidence, the isolated pathogenic bacteria strains and their antibiotic sensitivity, and the drug-resistant genotype of the pathogens were examined.

Results

The incidence of endophthalmitis in patients of group A was 0.8‰. Thirteen pathogenic bacterial strains were isolated from the patient samples in group A, including 8 strains of Staphylococcus epidermidis, 1 Staphylococcus aureus, 1 Streptococcus pneumoniae, 1 Streptococcus bovis, 1 Enterococcus faecium and 1 Morganella sp. The incidence of endophthalmitis in group B patients was 0.2‰, which was significantly lower than that in group A (P<0.05). Five strains of pathogenic bacteria were successfully isolated, including 2 strains of Enterococcus faecium, 1 Enterococcus faecalis, 1 Staphylococcus epidermidis and 1 Staphylococcus aureus. There was no significant difference in the proportion of Staphylococcus strains in all isolated bacteria between the two groups (P > 0.05). However, the proportion of Enterococci isolated in group B samples was higher than that in group A (P < 0.05). There were more gentamicin-sensitive strains than levofloxacin-sensitive strains identified (P < 0.05). Interestingly, aminoglycoside-inactivating enzyme resistance gene was detected in Enterococcus strains.

Conclusion

Our data suggest that gentamicin-containing perfusion solution can reduce the incidence of postoperative endophthalmitis in cataract patients. However, the selective pressure imposed by gentamicin may facilitate the development of aminoglycoside-resistant Enterococcos strains.

Remote Eradication of Bacteria on Orthopedic Implants via Delayed Delivery of Polycaprolactone Stabilized Polyvinylpyrrolidone Iodine

Bacteria-associated late infection of the orthopedic devices would further lead to the failure of the implantation. However, present ordinary antimicrobial strategies usually deal with early infection but fail to combat the late infection of the implants due to the burst release of the antibiotics. Thus, to fabricate long-term antimicrobial (early antibacterial, late antibacterial) orthopedic implants is essential to address this issue. Herein, we developed a sophisticated MAO-I₂-PCLx coating system incorporating an underlying iodine layer and an upper layer of polycaprolactone (PCL)-controlled coating, which could effectively eradicate the late bacterial infection throughout the implantation. Firstly, micro-arc oxidation was used to form a microarray tubular structure on the surface of the implants, laying the foundation for iodine loading and PCL bonding. Secondly, electrophoresis was applied to load iodine in the tubular structure as an efficient bactericidal agent. Finally, the surface-bonded PCL coating acts as a controller to regulate the release of iodine. The hybrid coatings displayed great stability and control release capacity. Excellent antibacterial ability was validated at 30 days post-implantation via in vitro experiments and in vivo rat osteomyelitis model. Expectedly, it can become a promising bench-to-bedside strategy for current infection challenges in the orthopedic field.

Vitreous Opacity Vitrectomy (VOV): Safest Possible Removal of “Floaters”

Purpose

Primary opacities that develop in the aging vitreous, commonly termed “floaters,” were once considered merely a nuisance, not justifying any risk of surgical removal. However, vitreoretinal specialists are increasingly recognizing that extensive symptomatic vitreous opacities (SVO) that substantially interfere with activities that critically depend on vision (daily visual activities, DVA), constituting degenerative vitreous syndrome (DVS, see http://floaterstories.com), warrant removal albeit with minimal risk - but no description of how to reduce vitrectomy risks to least possible has been forthcoming. We here describe such a method.

Patients and Methods

The safest possible removal of extensive SVO as described herein was attained by an operation specifically designed for DVS treatment (vitreous opacity vitrectomy, VOV), rather than as only a means of achieving subsequent retinal surgery in the same procedure, as is usually the case. We retrospectively reviewed the outcomes of 100 consecutive VOV operations (in 81 patients, average age 66) performed with ultra-high speed, 27-gauge vitrectomy probes.

Results

All eyes rapidly achieved continuously clear vision, and no eye developed a clinically significant complication during a year of follow-up. Three small, existent retinal breaks were discovered prior to peripheral vitrectomy and one apparently iatrogenic retinal tear was found at VOV completion, when each was treated. In the eyes that were not pseudophakic, postoperative nuclear sclerosis progression was successfully managed by subsequent cataract extraction.

Conclusion

The goals of VOV for DVS are to safely restore continuously clear vision by performing tractionless vitreous removal with respect to the retina and to reduce the lifetime risk of retinal detachment, both by such vitreous removal and by microscopic examination of the peripheral retina under anesthesia (MEPRUA), guiding appropriate prophylactic retinopexy. The otherwise healthy DVS eyes so treated warrant this specific form of vitrectomy, continually focused on achieving least possible risk, to maintain an acceptable risk/benefit ratio.

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Novel Combined Lidocaine/Povidone Iodine Delivery System for Preintravitreal Injection

Purpose: Intravitreal injection has become a popular treatment for various retina disorders and dramatically increased over the past few years. In traditional preintravitreal injection, the preparation steps are time consuming for practitioners who perform a significant number of injections per day. Besides, lidocaine gel (L-Gel) shows a potential absorption barrier on the antibacterial effect of povidone iodine (PI). Methods: In this study, we describe a L/PI gel system as an alternative approach to address these issues for traditional preinjection drug administration. Lidocaine and PI are loaded in a thermoresponsive gel instilled as a liquid to the lower fornix that transitions to a stable, solid gel depot. Results and Conclusion: The gel demonstrated decrease in conjunctival touch sensitivity and sufficient bacteria killing with a single step, suggesting a significant decrease in the time required and less potential for drug inhibition due to sequential administration.

Doctor I Have an Iodine Allergy

Ophthalmologists frequently face patients who refuse asepsis protocols involving povidone-iodine (PI) due to claims of an allergy to iodine. Such patients usually base this claim on previous reactions to shellfish consumption or to imaging procedures that used iodine-based contrast agents. Allergy to iodine, however, is biologically impossible, and iodine deficiency causes severe developmental problems, including mental retardation. Furthermore, shellfish allergy is due to tropomyosins in muscle tissue, and reactions to intravascular contrast dyes are due to hyperosmolar solutions; neither “allergy” is due to iodine. PI, which contains 9–12% iodine, is the preferred antiseptic for ophthalmic procedures. Experience shows that PI can be administered safely to patients claiming iodine allergy. True allergy to PI is rare and, if indicated, skin patch testing can be performed prior to surgery. Patients who react adversely to highly concentrated (5–10%) PI usually experience toxicity to the corneal and conjunctival epithelium after topical administration. Dilute (0.1–0.25%) PI kills microbes quicker than higher concentrations but for shorter periods of time because the total dose of iodine is smaller. Repeated administration (every 20–30 s) of dilute PI effectively kills microbes for as long as necessary with little risk of epithelial toxicity.

Antiseptics and the Ocular Surface: In Vitro Antimicrobial Activity and Effects on Conjunctival and Corneal Epithelial Cells of a New Liposomal Ocular Spray Containing Biosecur® Citrus Extract

Introduction

Methods

Results

Conclusion

[The role of local antiseptics in the prevention of coronavirus infection during endonasal interventions on the lacrimal ducts]

In connection with the pandemic of coronavirus infection, it is urgent to develop measures to prevent the intraoperative spread of coronavirus particles and infection of the operating room staff.

OBJECTIVE

Generalization and analysis of available data concerning local antiseptic therapy for the prevention of coronavirus infection during endonasal interventions on the lacrimal tract.

MATERIAL AND METHODS

The search for literature sources was carried out using MEDLINE search engines and the Russian Science Citation Index for queries with the keywords "COVID-19", "coronavirus infection", "antiseptics", "protocol for otorhinolaryngological operations", "dacryosurgical operations" and similar in various combinations.

RESULTS

It has been shown that during endonasal operations on the lacrimal tract, the number of risk factors for infection increases, since these procedures are aerosol-generating, and contact occurs not only with the nasal mucosa, but also with the lacrimal fluid, in which the coronavirus is also replicated. The data on the effectiveness of various antiseptics are summarized, the analysis of the possibility of their use in preoperative preparation for endonasal interventions on the lacrimal tract from the point of view of efficacy and safety is carried out. Information is provided on the proprietary protocol for the use of antiseptics to prevent the spread of coronavirus infection during endonasal dacryocystorhinostomy. It is shown that the preventive use of local disinfectants reduces the number of viral particles on the nasal mucosa, which leads to a decrease in contamination of the surrounding space. Among the available and studied antiseptics, the most suitable is povidone-iodine, which can be used in concentrations up to 1.25% to irrigate the nasal mucosa before surgery with an exposure of 30-60 sec. When performing operations on the lacrimal pathways, it is also advisable to carry out antiseptic treatment of the conjunctival cavity with a 5% solution of povidone-iodine and rinse the lacrimal pathways before the operation with povidone-iodine in a concentration of 0.4%.

CONCLUSION

To date, information has been obtained that makes it advisable to use antiseptics before performing endonasal aerosol-generating interventions, in particular endonasal dacryocystorhinostomies and recanalization of the tear ducts.

Chlorhexidine and other alternatives for povidone-iodine in ophthalmic surgery: review of comparative studies

Povidone-iodine (PVI) is a universally accepted antiseptic agent used in ophthalmic surgery. Insufficient antisepsis in patients with self-reported allergies to iodine has led to devastating complications. The aim of this study was to review the current evidence for alternatives to PVI in ocular surgery. Aqueous chlorhexidine has been used as a primary antiseptic agent in Sweden for several years and has proven efficiency and safety; in a study of a large series of intravitreal injections in Australia, the endophthalmitis rates were similar to those after the use of PVI. The evidence related to using other disinfectants such as picloxydine, hypochlorous acid solution, and polyhexanide is scarce. Single studies have shown lower patient discomfort after conjunctival lavage with chlorhexidine or hypochlorous acid than with PVI. No evidence was found to suggest changing from PVI to other antiseptic agents. Disinfectant solutions other than PVI or chlorhexidine will require further investigations to show their utility in ocular surgery.

The Role of Topical Povidone-Iodine in the Management of Infectious Keratitis: A Pilot Study

The aim of this prospective explorative study was to evaluate the safety and the effectiveness of topical polyvinylpyrrolidone-iodine (PVP-I) administered during the time-to-results period for pathogen identification and susceptibility testing in patients with infectious keratitis (IK). A corneal swab (CS) for antimicrobial evaluation was performed at enrollment (T0) and topical 0.66%-PVP-I was administered until the laboratory results were available (T1). Ulcer and infiltrate areas and infiltrate depths were compared between T0 and T1 (i.e., time-to-result period). Patients were then shifted to a specific antimicrobial therapy and followed up until resolution of their infiltrates (Tlast-TL). Twenty-five eyes were enrolled, and none showed clinical worsening leading to protocol withdrawal. At T1, ulcer and infiltrate areas showed significant improvement in Gram-positive IK (n = 13–52%; p = 0.027 and p = 0.019, respectively), remained stable in fungal IK (n = 5–20%; both p = 0.98) and increased in those with Gram-negative bacteria (n = 4–16%; p = 0.58 and p = 0.27). Eyes with negative cultures (n = 3–12%) showed complete resolution at T1 and did not initiate any additional antimicrobial therapy. The administration of 0.66% PVP-I during the time-to-result period seems to be a safe strategy in patients with IK while often sparing broad-spectrum antimicrobial agents. In addition, it showed to be effective in eyes with a Gram-positive bacterial infection.

Low-concentration povidone-iodine for the prevention of intraocular infections in ophthalmic surgery

PURPOSE OF REVIEW

Endophthamitis following intraocular surgery is rare using current antiseptic techniques, such as single application of 5% povidone-iodine to the ocular surface and adjuvant topical or intracameral antibiotics. Challenges remain, however, including increased multidrug-resistant bacterial endophthalmitis, increased fungal endophthalmitis, and the low but nonzero endophthalmitis rate attributable to the typical bacteria that colonize the ocular surface.

RECENT FINDINGS

Povidone-iodine has a wide spectrum of activity, including activity against novel pathogens, such as SARS-CoV-2. Povidone-iodine alternatives, such as hypochlorous acid can have significantly less efficacy in vitro against endophthalmitis isolates. Repetitive application of dilute povidone-iodine has an excellent safety profile and strong evidence base for efficacy.

SUMMARY

Povidone-iodine is widely available, inexpensive, and commonly used by ophthalmologists. The repetitive application of dilute povidone-iodine is a well studied, well tolerated, and efficacious way to transiently sterilize the ocular surface during intraocular surgery. Additional benefits include activity against multidrug-resistant bacteria, fungi, and lack of inducible resistance.

Analysis of retinal detachment resulted from post-operative endophthalmitis treated with 23G pars Plana Vitrectomy

Background

To evaluate the rate, risk factors, functional outcome and prognosis in eyes with retinal detachment after post-operative endophthalmitis treated with 23G Pars Plana Vitrectomy.

Methods

Electronic patient files from 2009 until 2018 were screened for the presence of an endophthalmitis. Included were 116 eyes of 116 patients. This population was evaluated for the rate of retinal detachment after 23G Pars Plana Vitrectomy for endophthalmitis following cataract surgery or intravitreal injection. The main outcome measures were retinal detachment and visual acuity.

Results

The reasons for endophthalmitis were previous cataract surgery in 78 patients and following intravitreal injection in 38 patients. The first clinical evidence of endophthalmitis was present in median 5 days after the triggering intervention. Twenty-five eyes (21.55%) developed a retinal detachment an average of 25 days after endophthalmitis. RD is significantly associated with preoperative visual acuity (p = 0.001).

Conclusions

We emphasize the prognostic role of preoperative visual acuity in RD development of the endophthalmitis treated with 23G Pars Plana Vitrectomy.

Effectiveness of liposomal ozonized oil in reducing ocular microbial flora in patients undergoing cataract surgery

PURPOSE

To evaluate the antimicrobial effectiveness of a liposomal ozonized oil solution used as a home therapy in patients undergoing cataract surgery. Antimicrobial efficacy was evaluated as the reduction in the bacterial load of the most common bacteria isolated from cases with endophthalmitis.

SETTING

20 Italian experimental centers of the Effectiveness of Liposomal Ozonized oil on Ocular Microbial flora before cataract surgery study group.

DESIGN

Interventional, nonrandomized, paired-eye designed, phase 4 clinical study.

METHODS

A total of 174 patients undergoing cataract surgery were divided into 2 groups: the study group (174 eyes) underwent surgery and received an isotonic ophthalmic solution of 0.5% ozonized oil in liposomes plus hypromellose treatment (2 drops 4 times/d), and the control group (174 contralateral eyes) was treated with saline solution. The treatment lasted for 3 days. Subconjunctival swabs were taken from both eyes of each patient at T0 (the day before starting the treatment and 4 days preoperatively) and at T4 (after 3 days of treatment and 10 min preoperatively) and sent to the laboratory within 24 hours of collection for microbiological analysis.

RESULTS

30% of 696 swabs taken at T0 were sterile. Contaminated swabs had a high prevalence of coagulase-negative staphylococci, including Staphylococcus epidermidis, and more than 60 different bacterial species were isolated. A significant reduction in microbial load was observed after treatment (>90% of the samples). The microbial load in the control group remained unchanged.

CONCLUSIONS

Liposomal ozonized oil reduced the microbial burden after topical administration in a large study population.

Comparative Evaluation of Bandage Contact Lenses and Eye Patching after Bilateral Cataract Surgery

Purpose

To comparatively evaluate the safety and satisfaction of bandage contact lens (BCL) and eye patching in patients after cataract surgery.

Methods

Sixteen (32 eyes) patients who planned to undergo bilateral cataract surgery were recruited. The two eyes of each patient were randomly divided into 2 groups. Group A and Group B were instructed to wear BCLs immediately at the end of the surgery until one week and eye patch immediately after surgery until one day, respectively. Visual analog scales of ten specific symptoms, Visual Function Index (VF-14) questionnaire, and best-corrected visual acuity (BCVA) were conducted on the first day before the surgery and Day 1 and Day 7 after surgery. Oculus keratography was conducted on the first day before surgery and on Day 7. Patient satisfaction was determined on Day 1. Moreover, bacterial species in the conjunctival sac, meibomian gland secretions, and BCLs were subsequently identified using 16S rRNA gene sequencing.

Results

The patient satisfaction scores of Group A were higher than Group B. Group A were more motivated to choose the same treatment and were more likely to recommend BCLs to others. No statistically significant differences were found in bacterial culture positivity between the groups. The differences in ocular signs and symptoms between the two groups were not statistically significant. There were no significant differences in the BCVA and VF-14 between the groups at any time point.

Conclusions

BCLs could be safely and effectively used in patients after cataract surgery.

Cataract Surgery by Intraoperative Surface Irrigation with 0.25% Povidone-Iodine

Postoperative endophthalmitis after cataract surgery is typically caused by the patient's own conjunctival normal bacterial flora. A three-step approach is recommended to prevent endophthalmitis: (1) "border control" to prevent microorganisms from entering the eye by disinfecting the ocular surface is the most important measure; (2) bacteria that have gained access into the anterior chamber are reduced by irrigation; (3) bacteria remaining in the anterior chamber and vitreous at the end of surgery are controlled by antibacterial drugs. We have devised a method, "the Shimada technique", for irrigating the ocular surface with povidone-iodine, a disinfectant with potent microbicidal effect and established effective and safe concentrations for eye tissues. Povidone-iodine exhibits a bactericidal effect for a wide concentration range of 0.005-10%, but 0.1% povidone-iodine has the highest activity and requires the shortest time of only 15 s to achieve microbicidal effect. When used to irrigate the ocular surface every 20-30 s during cataract surgery, 0.25% povidone-iodine is conceivably diluted to around 0.1%. Irrigation with 0.25% povidone-iodine during cataract surgery significantly reduced bacteria contamination rate in the anterior chamber compared with saline (p = 0.0017) without causing corneal endothelial damage.

Preoperative antisepsis in ophthalmic surgery (a review)

Endophthalmitis remains a serious complication following intraocular procedures. Preoperative prophylactic measures for endophthalmitis decrease the morbidity associated with this disease and represent a standard of care prior to ophthalmic surgery. The literature supports as measures for ocular antisepsis: povidone-iodine solution for ocular surface preparation, chlorhexidine in patients with iodine allergy and application of topical antibiotics. Povidone-iodine is regarded as the most effective antiseptic associated with significant reduction in ocular surface bacterial counts. Currently, the recommended preoperative management is the application of 5% povidone-iodine solution in the conjunctival fornix, prior to surgery. This paper reviews the preoperative measures for ocular antisepsis, used in order to decrease the risk of culture-proven endophthalmitis.

Post-injection endophthalmitis rates with reduced povidone-iodine prophylaxis in patients with self-reported iodine sensitivity

BACKGROUND

Our objectives were (1) to report the post-injection endophthalmitis rate over 18 months, and (2) to determine any difference in the incidence of endophthalmitis in patients treated with reduced or no 5% povidone-iodine (PI) due to self-reported PI sensitivity.

METHODS

We performed a retrospective cohort study of all patients who received intravitreal injections (IVIs) from January 1st, 2018 to June 26th, 2019. Information on patients' age, gender visual acuities, the number of injections, drug administered, self-reported iodine sensitivity and injection protocols were obtained from electronic and paper records. For endophthalmitis cases, vitreous culture results and treatment were also noted. Patients were divided into three cohorts based on the injection protocol used for statistical analysis.

RESULTS

During the study period 22,046 IVIs were administered to 3332 eyes of 2709 patients. Intolerance to PI was reported by 2.4% of patients. The incidence of endophthalmitis was 0.02% (4/21,185) with the standard 5% PI protocol, 0.78% (6/769) with a reduced PI protocol involving fewer drops of 5% PI and chlorohexidine 0.05% for periorbital skin cleansing, and 1.09% (1/92) without any PI use. Receiving the standard PI protocol was associated with significantly lower rates of endophthalmitis compared to both the reduced PI and no PI protocols (p < 0.0001).

CONCLUSIONS

Patients who opt for less or no PI use are likely at significantly increased risk of developing post-IVI endophthalmitis. It is imperative to educate, counsel and consent these patients accordingly while exploring alternative antiseptic solutions.

Ex vivo evaluation of the influence of pH on the ophthalmic safety, antibacterial efficacy and storage stability of povidone-iodine

CLINICAL RELEVANCE

The monitoring and controlling of pH is important when preparing solutions for ophthalmic administration. In the case of povidone-iodine, dilution in an appropriate buffer is needed to improve its ophthalmic safety.

BACKGROUND

Povidone-iodine is a broad-spectrum antiseptic agent that is commonly used in ophthalmic applications due to its cost-effectiveness and accessibility. However, native povidone-iodine has a pH of about 4.0 and is known to irritate the ocular surface. This study assessed whether adjusting povidone-iodine formulation pH would influence its ex vivo ophthalmic safety, alongside its impact on antibacterial efficacy and storage stability.

METHODS

One per cent w/v povidone-iodine was diluted in normal saline, or 0.1-mol/l citrate or phosphate buffers to yield solutions with a pH ranging from 4.0 to 7.0. Ocular irritancy was evaluated using the bovine cornea opacity and permeability assay. Antibacterial efficacy was assessed by evaluating povidone-iodine minimum inhibitory concentration and minimum bactericidal concentration at varied pH. Storage stability of the preparations was determined over 30-days at room temperature (20-25°C).

RESULTS

Combining povidone-iodine with phosphate buffer notably decreased ocular irritancy of the antiseptic. Surprisingly, combining povidone-iodine with citrate buffer potentiated irritant effects of the preparation. Antibacterial efficacy of povidone-iodine was reduced when formulation pH was increased from 4.0 to 7.0, although its general activity was retained. Finally, povidone-iodine remained stable in both normal saline and phosphate buffer over 30-days.

CONCLUSION

Ophthalmic application of povidone-iodine can be optimised by adjusting the pH of the formulation to 7.0 using phosphate buffer, reducing irritancy while maintaining adequate antibacterial efficacy and storage stability.

Sub-Tenon's anaesthesia for modern eye surgery-clinicians' perspective, 30 years after re-introduction

Sub-Tenon's block (STB) is a good technique of local anaesthesia for many types of eye surgery. It has a relatively good risk profile, in that sight- and life-threatening complications appear to be extremely rare. STB has gained popularity in the last three decades, with refinements including different types of blunt metal cannula, plastic cannulae and 'incisionless' approaches. Usage of STB varies significantly across the globe. This narrative review documents the historical evolution of STB techniques, anatomical and physiological considerations, its utility and suitability, complications, explores the current practice and possible future applications.

Cataract surgery practice patterns worldwide: a survey

Objective

To report the results of a global survey on cataract practice patterns related to preoperative, intraoperative and postoperative care, surgical setting and personnel allocation.

Methods and analysis

An online 28 questions survey was sent to 240 ophthalmologists asking to describe prevailing trends in their institutions across 38 countries and 5 continents. Questions inquired country, institution, surgical volume and setting, anaesthesia, preoperative and intraoperative examination and postsurgical care. Statistical analysis used crosstabs lambda statistics for non-parametric nominal variables. P value less than 0.05 was considered statistically significant.

Results

209/240 (87%) ophthalmologists responded: 38% representing public hospitals, 36% private practices and 26% academic sites; overall surgical volume was between 241 700 and 410 500 cataracts per year. There was a significant correlation between type of institution and surgical volume. Complete results available in online (https://freeonlinesurveys.com/r/W6BcLLxy).

Conclusion

Cataract surgery related patterns of perioperative care showed significant difference among respondents, regardless to type of institution, surgical volume and country. Many evidence-based procedures are unevenly practiced around the world and some widespread and expensive habits lack solid scientific evidence while consuming enormous amount of resources both monetary and human. There is a need to reach consensus and share evidence-based practice patterns.

The Use of Chlorhexidine as a Skin Preparation on the Head and Neck: A Systematic Review of Ocular and Ototoxicity

BACKGROUND

Chlorhexidine gluconate is one of the most effective surgical preparations, but it has known potential ocular and ototoxicity.

OBJECTIVE

To review reported cases of ocular and ototoxicity caused by chlorhexidine and summarize the clinical situations in which chlorhexidine toxicity occurred.

METHODS

We performed a systematic review of PubMed and the Web of Science.

RESULTS

Fourteen cases reported sensorineural hearing loss from chlorhexidine instilled into the ear. Of the 38 cases of ocular toxicity, 8 cases were caused by direct instillation in the eye and 17 involved periocular surgical preparation. In the remaining cases, the area prepped was less defined. Seven cases involved preparation of the face, 1 for the scalp, 2 cases were drips from distant sites, and 3 cases did not specify the means of exposure.

CONCLUSION

The vast majority of toxicity occurred in patients undergoing general anesthesia and was rarely seen in situations where surgery was performed by dermatologists. Ultimately, it should be up to the individual physician to decide whether chlorhexidine is the best choice for a particular outpatient procedure.

Safety and Tolerability of an Eye Drop Based on 0.6% Povidone-Iodine Nanoemulsion in Dry Eye Patients

Purpose: To evaluate safety and tolerability on the ocular surface of an anti-septic formulation containing 0.6% povidone–iodine (0.6% PVI) for a 4 week period.

Methods: An observational, prospective study included 20 mild-moderate dry eye disease (DED) patients who enrolled at the Ocular Surface Disease Unit of the University of Messina, receiving 0.6% PVI eye drops for 28 days, 2 drops twice daily (BID). The assessment included the Ocular Surface Disease Index questionnaire; symptoms score (0 = absent to 3 = severe) for burning, ocular dryness, foreign body sensation, watery eyes, tearing, photophobia, and ocular pain; fluorescein tear break-up time (TBUT); and corneal-conjunctival staining, performed at baseline (T0), after 7 (T7) and 28 (T28). Schirmer I-test, corneal endothelial cell count, intraocular pressure, and fundus examination were performed at T0 and T28. The main outcome measures were TBUT and corneal-conjunctival staining as markers of ocular surface homeostasis. For statistical analysis, Student's T-test and Wilcoxon test were used as appropriate.

Results: No significant alterations of the safety parameters were found throughout the study. Further, at T28 a significant improvement of burning, ocular dryness, foreign body sensation, and watery eyes (T0 vs. T28 P < 0.03) were observed; corneal-conjunctival staining improved at T28 (T0 vs. T28 P < 0.0001), and TBUT improved already at T7 (T0 vs. T7 P = 0.0008) lasting so till the end of the study. The only adverse event was mild burning at instillation for the first 3 days of treatment in most of the patients.

Conclusions: The treatment with 0.6% PVI was safe and well tolerated in a group of patients with a damaged ocular surface.

Polymeric Iodophors: Preparation, Properties, and Biomedical Applications

The review summarizes the data on the main chemical and physiological properties of iodine and its capability of complexation with natural and synthetic polymers. Iodine is the best known antiseptic used to prevent and treat microbial infections. Its unique capability of complexation with certain polymers opens wide opportunities for targeted and prolonged delivery to target organs. Polymeric complexes with iodine have another color, other morphology, a higher electrical conductivity, and higher biological activity as compared with initial polymers. The formation of and ions is associated with iodine-polymer complexation. Iodine-containing biocompatible adhesive controlled-release formulations are designed as part of research into iodine-polymer complexes. The field is promising in terms of treating certain diseases because tolerance to iodine compounds does not usually develop in microbial cells.

Rethinking Elective Cataract Surgery Diagnostics, Assessments, and Tools after the COVID-19 Pandemic Experience and Beyond: Insights from the EUROCOVCAT Group

The progressive deterioration of the visual function in patients on waiting lists for cataract surgery has a negative impact on their quality of life, especially in the elderly population. Patient waiting times for cataract surgeries in many healthcare settings have increased recently due to the prolonged stop or slowdown of elective cataract surgery as a result of coronavirus disease 19 (COVID-19). The aim of this review is to highlight the impact of such a "de-prioritization" of cataract surgery and to summarize some critical issues and useful hints on how to reorganize cataract pathways, with a special focus on perioperative diagnostic tools during the recovery phase and beyond. The experiences of a group of surgeons originating from nine different countries, named the European COVID-19 Cataract Group (EUROCOVCAT), have been combined with the literature and recommendations from scientific ophthalmic societies and healthcare institutions. Key considerations for elective cataract surgery should include the reduction of the number of unnecessary visits and examinations, adoption of precautionary measures, and implementation of telemedicine instruments. New strategies should be adopted to provide an adequate level of assistance and to guarantee safety conditions. Flexibility will be the watchword and regular updates would be necessary following scientific insights and the development of the pandemic.

Evolution of and developments in simultaneous bilateral cataract surgery. Update 2020

The debate on role of ‘simultaneous bilateral cataract surgery’ (SBCS) continues. The world population has exponentially increased during last fifty years and average human lifespan has increased by a decade during the last century. This translates to ever increasing geriatric population with its inherent problem of preventable blindness because of cataract formation in the elderly. We are adding to the backlog of cataract surgeries not only in the ‘developing world’ but also in the ‘developed world.’ Times demand that we reconsider our old fashioned approach of staggering bilateral cataract surgeries. Serious, but a potential, risk of simultaneous bilateral infection/endophthalmitis has been the biggest deterrent in acceptance of SBCS as a routine procedure. The opponents of SBCS strongly believe in this argument that has not been documented when strictly followed the recommendations regarding separate procedures of each eye. The advantages of reducing the ever-increasing backlog of preventable/treatable blindness, faster visual recovery, economic benefits to patients as well as health care providers, lesser risk of amblyopia in pediatric population, and decreased risk of as serious a complication as death by exposure to general anesthesia in pediatric and adult population, etc. outweigh the disadvantages of SBCS when compared with ‘delayed bilateral cataract surgery’ (DBCS). SBCS is favored over DBCS in pediatric population and in uncooperative, mentally retarded and physically disabled adults needing general anesthesia to reduce the risks and complications of general anesthesia. Considering such factors and review of available literature strongly support that SBCS has a definite role where indicated, under certain circumstances, and in certain select group of patients in both developing as well as developed countries.

A new pharmacological approach based on remdesivir aerosolized administration on SARS-CoV-2 pulmonary inflammation: A possible and rational therapeutic application

The new zoonotic coronavirus (SARS-CoV-2) responsible for coronavirus disease (COVID-19) is a new strain of coronavirus not previously seen in humans and which appears to come from bat species. It originated in Wuhan, Hubei Province, China, and spread rapidly throughout the world, causing over 5,569,679 global cases and 351,866 deaths in almost every country in the world, including Europe, particularly Italy. In general, based on existing data published to date, 80.9% of patients infected with the virus develop mild infection; 13.8% severe pneumonia; 4.7% respiratory failure, septic shock or multi-organ failure; 3% of these cases are fatal. Critical patients have been shown to develop acute respiratory distress syndrome (ARDS) and hospitalization in intensive care units. The average age of patients admitted to hospital is 57-79 years, with one third half with an underlying disease. Asymptomatic infections have also been described, but their frequency is not known. SARS-CoV-2 transmission is mainly airborne from one person to another via droplets. The data available so far seem to indicate that SARS-CoV-2 is capable of producing an excessive immune reaction in the host. The virus attacks type II pneumocytes in the lower bronchi through the binding of the Spike protein (S protein) to viral receptors, of which the angiotensin 2 conversion enzyme (ACE2) receptor is the most important. ACE2 receptor is widely expressed in numerous tissues, including the oropharynx and conjunctiva, but mostly distributed in ciliated bronchial epithelial cells and type II pneumocytes in the lower bronchi. The arrival of SARS-CoV-2 in the lungs causes severe primary interstitial viral pneumonia that can lead to the "cytokine storm syndrome", a deadly uncontrolled systemic inflammatory response triggered by the activation of interleukin 6 (IL-6), whose effect is extensive lung tissue damage and disseminated intravascular coagulation (DIC), that are life-threatening for patients with COVID-19. In the absence of a therapy of proven efficacy, current management consists of off-label or compassionate use therapies based on antivirals, antiparasitic agents in both oral and parenteral formulation, anti-inflammatory drugs, oxygen therapy and heparin support and convalescent plasma. Like most respiratory viruses can function and replicate at low temperatures (i.e. 34-35 °C) and assuming viral thermolability of SARS-CoV-2, local instillation or aerosol of antiviral (i.e. remdesivir) in humid heat vaporization (40°-41 °C) in the first phase of infection (phenotype I, before admission), both in asymptomatic but nasopharyngeal swab positive patients, together with antiseptic-antiviral oral gargles and povidone-iodine eye drops for conjunctiva (0,8-5% conjunctival congestion), would attack the virus directly through the receptors to which it binds, significantly decreasing viral replication, risk of evolution to phenotypes IV and V, reducing hospitalization and therefore death.

Hypochlorous acid antiseptic washout improves patient comfort after intravitreal injection: A patient reported outcomes study

Purpose:

Current ocular antiseptic practice for intravitreal injection (IVI) employs 5% povidone–iodine (Betadine^®) drops which frequently cause ocular discomfort and prolonged irritation. In an effort to improve comfort while maintaining efficacy, we studied a hypochlorous acid (HOCL 0.01%) spray washout prior to injection.

Methods:

Patients had received a minimum of 3 IVIs prepared with Betadine^® antisepsis prior to entry in this study. Their subsequent IVIs were prepared with Betadine^® followed by HOCL 0.01% washout. Facets of comfort were measured by a Likert-scaled questionnaire to compare their experiences after IVI.

Results:

Thirty-seven participants were enrolled. Addition of HOCL 0.01% spray after Betadine^® reduced the duration of discomfort (P = 0.001) and need for artificial tears postinjection (P = 0.003). It improved their reported quality of life (P = 0.04) and sleep (P = 0.01). There were neither HOCL-related side effects nor endophthalmitis during this study.

Conclusion:

Topical HOCL 0.01% spray after topical Betadine^® antisepsis significantly improved patient comfort following IVIs.

Povidone iodine treatment is deleterious to human ocular surface conjunctival cells in culture

Objective

To determine the effect of povidone iodine (PI), an antiseptic commonly used prior to ocular surgery, on viability of mixed populations of conjunctival stratified squamous and goblet cells, purified conjunctival goblet cells and purified conjunctival stromal fibroblasts in primary culture.

Methods and analysis

Mixed population of epithelial cells (stratified squamous and goblet cells), goblet cells and fibroblasts were grown in culture from pieces of human conjunctiva using either supplemented DMEM/F12 or RPMI. Cell type was evaluated by immunofluorescence microscopy. Cells were treated for 5 min with phosphate-buffered saline (PBS); 0.25%, 2.5%, 5% or 10% PI in PBS; or a positive control of 30% H₂O₂. Cell viability was determined using Alamar Blue fluorescence and a live/dead kit using calcein/AM and ethidium homodimer-1 (EH-1).

Results

Mixed populations of epithelial cells, goblet cells and fibroblasts were characterised by immunofluorescence microscopy. As determined with Alamar Blue fluorescence, all concentrations of PI significantly decreased the number of cells from all three preparation types compared with PBS. As determined by calcein/EH-1 viability test, mixed populations of cells and fibroblasts were less sensitive to PI treatment than goblet cells. All concentrations of PI, except for 0.25% used with goblet cells, substantially increased the number of dead cells for all cell populations. The H₂O₂ control also significantly decreased the number and viability of all three types of cells in both tests.

Conclusion

We conclude that PI, which is commonly used prior to ocular surgeries, is detrimental to human conjunctival stratified squamous cells, goblet cells and fibroblasts in culture.

A new ophthalmic formulation containing antiseptics and dexpanthenol: In vitro antimicrobial activity and effects on corneal and conjunctival epithelial cells

Antibiotic resistance is increasing even in ocular pathogens, therefore the interest towards antiseptics in Ophthalmology is growing. The aim of this study was to analyze the in vitro antimicrobial efficacy and the in vitro effects of an ophthalmic formulation containing hexamidine diisethionate 0.05%, polyhexamethylene biguanide (PHMB) 0.0001% disodium edetate (EDTA) 0.01%, dexpanthenol 5% and polyvinyl alcohol 1.25% (Keratosept, Bruschettini, Genova, Italy) on cultured human corneal and conjunctival cells. The in vitro antimicrobial activity was tested on Staphylococcus aureus, Methicillin-Resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa, Streptococcus pneumoniae, Streptococcus pyogenes and Streptococcus mitis. For each microbial strain 10 μL of a 0.5 MacFarland standardized bacterial inoculum were incubated at 25 °C with 100 μL of ophthalmic solution for up to 6 h. After different periods of time, samples were inoculated on blood agar with 5% sheep blood. Moreover, a 0.5 MacFarland bacterial inoculum was seeded in triplicate on Mueller-Hinton Agar or on Mueller-Hinton Fastidious Agar; then a cellulose disc soaked with 50 μL of ophthalmic solution was applied on the surface of agar and plates were incubated for 18 h at 37 °C, in order to evaluate the inhibition of bacterial growth around the disc. Human corneal and conjunctival epithelial cells in vitro were incubated for 5, 10 and 15 min with Keratosept or its components. The cytotoxicity was assessed through the release of cytoplasmic enzyme lactate dehydrogenase (LDH) into the medium immediately after exposure to the drugs; the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was performed to evaluate the metabolic cell activity. Our results show that Keratosept ophthalmic solution gave an average logarithmic (log) reduction of bacterial load of 2.14 ± 0.35 within 6 h of exposure (p-value < 0.05 versus control saline solution). On agar plates, all microbial strains, excluding P. Aeruginosa, showed an inhibition zone of growth around the Keratosept-soaked discs. Keratosept and its components after 5 and 10 min did not show any cytotoxic effect on cultured corneal and conjunctival cells, and only after 15 min a significant reduction of cell viability and an increase of cytotoxicity compared to control (vehicle) was seen; dexpanthenol 5% and polyvinyl alcohol accelerated the wounding of corneal cells in vitro. In conclusion, Keratosept showed good antimicrobial activity on the tested strains; the ophthalmic solution and its components were safe and non-toxic for the corneal and conjunctival epithelial cells for 5 and 10 min at the concentrations analyzed, and dexpanthenol 5% and polyvinyl alcohol promoted the wounding of corneal cells.

Repurposing 0.5% povidone iodine solution in otorhinolaryngology practice in Covid 19 pandemic

SARS CoV 2 is very much homologous in structure to SARS CoV. Review of literature suggests the in-vitro virucidal action of povidone iodine in SARS CoV and MERS. The oropharynx and nasopharynx are target sites of SARS CoV 2. A significant proportion of COVID 19 sufferers are asymptomatic, but shedding these viral particles, PVP-I has been shown to be a safe therapy when used as a mouthwash or taken nasally or used during ophthalmic surgeries.

AIMS

MATERIALS AND METHODS: 0.5% PVP-I solution is prepared from commercially available 10% PVP-I solution. Patients were instructed to put 0.5% PVP-I drops in nose and rinse mouth with gargle prior examinations for 30 s. For endoscopic procedure (nasal and throat) nasal douching and gargling to be started one day prior. Douching and rinsing to be repeated just before procedures. Nasal packing with 0.5% PVP-I along with 4% xylocaine/adrenaline solution, tolerability and any allergic reaction noted.

RESULTS

The patient and health care workers tolerated the 0.5%. No allergy was noted.

CONCLUSION

We propose the use of 0.5% PVP-I in healthcare workers and their patients to minimise the risk of spread of the disease in addition to the recommended PPE.

A Prospective, Randomized Trial of Povidone-Iodine 0.6% and Dexamethasone 0.1% Ophthalmic Suspension for Acute Bacterial Conjunctivitis

PURPOSE

To evaluate the efficacy and safety of a topical ophthalmic suspension combination of povidone-iodine 0.6% (PVP-I) and dexamethasone 0.1% (DEX) for infectious and inflammatory components of bacterial conjunctivitis.

DESIGN

Randomized, double-masked, multicenter, phase 3 clinical trial.

METHODS

Subjects of all ages (those <3 months had to be full-term) with a diagnosis of bacterial conjunctivitis were randomized 3:1:3 to either PVP-I/DEX, PVP-I alone, or placebo. The primary endpoint was clinical resolution in the study eye, and the key secondary efficacy endpoint was bacterial eradication, both at the day 5 visit. Adverse events (AEs) were documented at all visits.

RESULTS

Overall, 753 subjects were randomized (intent-to-treat [ITT] population; PVP-I/DEX [n = 324]; PVP-I [n = 108]; placebo [n = 321]); mean and standard deviation (SD) age was 44.3 (22.9) years, and most were female (61.2%) and white (78.1%). In all treatment groups, mean treatment compliance was >98%. The modified ITT population for the efficacy analysis comprised 526 subjects. In the study eye at the day 5 visit, clinical resolution was achieved by 50.5% (111/220) subjects in the PVP-I/DEX group vs 42.8% (95/222) in the placebo group (P = .127), and bacterial eradication was achieved by 43.3% (94/217) and 46.8% (102/218), respectively (P = .500). Treatment-emergent AEs were experienced by 32.8% (106/323), 39.8% (43/108), and 19.0% (61/321) of subjects in the safety population treated with PVP-I/DEX, PVP-I, and placebo, respectively (most mild in severity).

CONCLUSION

In this study, PVP-I/DEX did not demonstrate additional benefit in clinical efficacy compared with placebo in subjects with bacterial conjunctivitis.

Corneal Ulcer Treated with 0.66% Nanoemulsion Povidone-Iodine: A Case Report

Patient: Male, 61-year-old

Final Diagnosis: Corneal ulcer

Symptoms: Pain • redness • watering • photophobia

Medication: —

Clinical Procedure: IODIM therapy

Specialty: Ophthalmology

The Effectiveness of 0.6% Povidone Iodine Eye Drops in Reducing the Conjunctival Bacterial Load and Needle Contamination in Patients Undergoing Anti-VEGF Intravitreal Injection: A Prospective, Randomized Study

The study purpose was to assess the efficacy of a preservative-free 0.6% povidone iodine eye drops as perioperative prophylactic treatment for reducing conjunctival bacterial load and the rate of needle contamination in patients undergoing intravitreal anti-vascular endothelial growth factor injection. Enrolled patients were randomized to either the study group (0.6% povidone iodine, three day-prophylactic treatment before the injection) or to the control group (placebo, three day-prophylactic treatment). Conjunctival swabs were obtained before and after the prophylactic treatment in both groups. Intravitreal injections were performed in a sterile fashion. The injection needle and a control needle were collected for microbiological culture. Data from 254 and 253 eyes in the study group and control group, respectively, were analyzed. Bacterial growth from conjunctival swab cultures was significantly lower after 0.6% povidone iodine prophylaxis compared to baseline and to placebo prophylaxis (p < 0.001), showing an 82% eradication rate in the study group. No injection needle showed bacterial contamination in the study group, whereas six needles were culture-positive in the control group (p = 0.015). No serious ocular and non-ocular adverse events were recorded. The 0.6% povidone iodine solution proved an effective treatment in reducing conjunctival bacterial load and risk of needle contamination.

Low Efficacy of Hypochlorous Acid Solution Compared to Povidone-iodine in Cataract Surgery Antisepsis

Background:

Hypochlorous Acid Solution (HAS) is a non-irritating, odorless and transparent, pH-neutral substance having antimicrobial activity.

Objective:

The study aimed to compare the efficacy of HAS with a 10% povidone-iodine (PVI) solution for antisepsis in Phacoemulsification Cataract Surgery (PCS).

Methods:

Consecutive patients undergoing PCS in the Elbląg City Hospital, Poland, were enrolled in this prospective trial. In the morning just before surgery a swab was taken from the inferior conjunctival fornix of the eye that was to be operated. Patients were assigned to receive conjunctival irrigation with PVI or HAS in the operating room. Three minutes after lavage with PVI or HAS, conjunctival swabs were taken. During surgery the cornea and conjunctival sac were irrigated with Ringer’s lactate. The last swab was taken before removing the eye speculum.

Results:

Overall, 110 patients completed the study; there were 59 patients in the PVI group and 51 patients in the HAS group. Conjunctival lavage with 10% PVI resulted in a decrease in bacterial load, while HAS application did not. In the HAS group a reduction in bacterial load was found after surgery. Patients after HAS irrigation reported significantly less discomfort associated with conjunctival lavage than with PVI. None of the patients developed postoperative endophthalmitis or any type of eye inflammation within the follow-up period.

Conclusions:

This study confirms the excellent antibacterial activity of a 10% povidone-iodine solution used for three minutes before cataract surgery. Conjunctival irrigation with Ringer lactate during PCS decreased the bacterial load of the conjunctival sac.