Efficacy and safety of low-concentration, bisulphite-containing, intracameral epinephrine and topical atropine treatments for the prevention of intraoperative floppy iris syndrome

Prospective analysis of anatomic features predisposing patients to intraoperative floppy iris syndrome

PURPOSE

To aid preoperative risk assessment by identifying anatomic parameters corresponding with a higher risk of intraoperative floppy iris syndrome (IFIS) during cataract surgery.

METHODS

Prospective cohort study of 55 patients with α1-adrenergic receptor antagonist (α1-ARA) treatment and 55 controls undergoing cataract surgery. Anterior segment optical coherence tomography (AS-OCT), video pupilometer, and biometry measurements were performed preoperatively and analyzed regarding anatomic parameters that corresponded with a higher rate of IFIS. Those statistically significant parameters were evaluated with logistic regression analysis and receiver operating characteristic (ROC) curve.

RESULTS

Pupil diameter was significantly smaller in patients who developed IFIS compared to those who did not develop IFIS (AS-OCT 3.29 ± 0.85 vs. 3.63 ± 0.68, p = 0.03; Pupilometer 3.56 ± 0,87 vs. 3.95 ± 0.67, p = 0.02). Biometric evaluation revealed shallower anterior chambers in the IFIS group (ACD 3.12 ± 0.40 vs. 3.32 ± 0.42, p = 0.02). Cutoff values for 50% IFIS probability (p = 0.5) were PD = 3.18 mm for pupil diameter and ACD = 2.93 mm for anterior chamber depth. ROC curves of combined parameters were calculated for α1-ARA medication with pupil diameter and anterior chamber depth, which yielded an AUC of 0.75 for all IFIS grades.

CONCLUSION

The combination of biometric parameters with history of α1-ARA medication can improve assessment of risk stratification for IFIS incidence during cataract surgery.

Factors predisposing to intraoperative floppy-iris syndrome: An up-to-date meta-analysis

Intraoperative floppy-iris syndrome (IFIS) is an increasingly recognized condition that is proven to lead to higher rates of intraoperative complications. This study provides an updated systematic review and meta-analysis regarding all the identified factors predisposing to IFIS. The study was performed in accordance with the PRISMA guidelines. 38 studies were finally included in the meta-analysis. The factors that were found to predispose to IFIS significantly were male sex (odds ratio [OR], 4.25; CI, 2.58-7.01), hypertension (OR, 1.55; CI, 1.01-2.37), tamsulosin (OR, 31.06; CI, 13.74-70.22), finasteride (OR, 4.60; CI, 1.97-10.73), benzodiazepines (OR, 2.88; CI, 1.17-7.12), and antipsychotics intake (OR, 6.91; CI, 2.22-21.50). A decreased dilated pupil preoperatively was found predisposing to IFIS (weighted mean difference -0.93; CI, -1.19 to -0.67). Intracameral epinephrine, which was investigated as a potential prophylactic measure for preventing IFIS, did not reach statistical significance (OR, 0.29; CI, 0.08-1.06). A comprehensive preoperative assessment of all risk factors is vital to stratify the surgical risk, which is crucial in addressing IFIS because unanticipated IFIS could turn a routine surgery into one of significant visual morbidity.

A novel ratiometric sensor prepared based aggregation-induced emission for ultrafast detection of SO2 derivatives in food samples and living cells

As one of the gaseous signaling molecules, aberrant levels of SO₂ are usually associated with many diseases. it is of great significance to develop sensitive methods for detection SO₂ on real. In this paper, a D-π-A near-infrared aggregation-induced fluorescent probe (DPA-CN) was built using diphenylamino-4-benzaldehyde and malononitrile for sensing SO₂. The DPA-CN exhibit AIE characterization that can quickly recognize SO₂ via the Michael addition mechanism. The DPA-CN displayed emission blue drift from 650 nm to 560 nm after adding SO₂, thereby realizing rapid and sensitive colorimetric detection of SO₂. The mechanism for recognition of SO₂ was verified via magnetic resonance imaging ⁽¹H NMR), electrospray ionization mass spectrometry (ESI-MS), scanning electron microscopy (SEM) and dynamic light scattering (DLS). The DPA-CN realized rapid and sensitive recognition of SO₂ with high specificity in 10 s within the concentration range of 0-100 μM. The limit of detection (LOD) is as low as 0.31 μM. Owing to its high sensitivity and low toxicity, the DPA-CN can be applied in monitoring of SO₂ in living cells and food analysis. Furthermore, the DPA-CN was used to prepare a visible and ultrafast semiquantitative paper-based SO₂ sensor with low cost and easy operation.

Dealing with floppy iris syndrome

PURPOSE OF REVIEW

The aim of this study was to review and summarize recent findings and advancements regarding intraoperative floppy iris syndrome (IFIS). Although many improvements have been made for the management of IFIS, it remains a challenging condition for surgeons. An understanding of the syndrome as well as the multitude of tools to mitigate risk of complication is important for surgeons operating on high-risk patients.

RECENT FINDINGS

A variety of management approaches have been modified and improved or further supported with new data, such as intracameral compounds, intraoperative devices and surgical techniques.

SUMMARY

An understanding of risk factors is important for the identification of at-risk patients. A variety of approaches can greatly reduce incidence of IFIS complications. Multiple management strategies should be utilized to further reduce risk during these difficult surgeries.

Preoperative atropine and non-steroidal anti-inflammatory drugs for the prevention of intraoperative floppy iris syndrome

PURPOSE

To examine the efficacy of preoperative administration of topical atropine 1% and non-steroidal anti-inflammatory drugs (NSAIDs) for prevention of intraoperative floppy iris syndrome (IFIS).

METHODS

In this retrospective cohort study, patients who underwent cataract surgery by phacoemulsification between July 2019 and February 2020 in two hospitals were included. Both hospitals are located in central Israel, have similar patient demographics and employ similar surgical techniques. They, however, differ in policy of IFIS prevention. In Meir Medical Center no preventive medications are given pre-operatively, while in Shamir Medical Center patients at-risk for IFIS receive topical atropine 1% once daily and non-steroidal anti-inflammatory drugs (NSAIDs) thrice daily for 3 days preoperatively.

RESULTS

Overall, 207 eyes of 207 patients with history of alpha-antagonist use were included. Mean age was 74.9 ± 7.8 years and 82.1% (n = 170) were male. Among patients from the pretreating center 86.8% (n = 92/106) were pre-treated with either NSAIDs or atropine preoperatively, while in the non-pretreating center no treatment was prescribed (n = 0/101). IFIS rate among the non-pretreating center was 29.7% (n = 30/101) compared to 15.1% (n = 16/106) in the pretreating center (p = 0.012). When strictly comparing treated to untreated patients, the treated group had an IFIS rate of 12.0% compared to 30.4% among untreated (p = 0.001). Adjusted for age and gender results remain consistent (odds ratio 0.329 for treated patients, 95% confidence interval: 0.150-0.720; p = 0.005).

CONCLUSIONS

IFIS rates were significantly lower in the pretreating center compared to the non-pretreating center. When comparing strictly treated to untreated patients, differences were even more pronounced.

Predictive value of pupillography on intraoperative floppy iris syndrome in preoperative period

AIM

To present the frequency of intraoperative floppy iris syndrome (IFIS) in cataract patients who taking alpha 1-a receptor antagonist (ARA) drugs, and evaluate the predictive value of pupil diameter (PD) changes in IFIS patients.

METHODS

Male cataract patients who are under treatment with alpha-1a-ARAs (alfuzosin, tamsulosin) intraoperatively were evaluated and were grouped as with/without IFIS. The preoperative PD values were compared with controls. Also, the intraoperative manipulations and early/late complications were recorded.

RESULTS

A total of 77 patients (77 eyes) of 94 benign prostate hyperplasia (BPH) patients have been defined as IFIS (81.91%) and 40 patients (40 eyes) were taking tamsulosin and 37 patients (37 eyes) were taking alfuzosin. During the cataract surgery, the rate of posterior capsular rupture (P=0.754), vitreous loss (P=0.585), iris tears (P=0.004), and iris catching (P=0.000) were higher in IFIS group, but the difference was significant only in the iris catching. At the postoperative first-month visit, persistent IOP rise and iris stromal tears were more frequent in IFIS group, but the difference was not significant (P=0.311, P=0.146; respectively). In contrast, Descemet membrane detachment was insignificantly more frequent in controls (P=0.311). In IFIS and control patients, PDs were 9.54±1.78 and 9.72±1.57 mm (P=0.255) under scotopic illumination, 8.54±1.43 and 8.74±1.25 mm (P=0.289) under mesopic illumination, 6.99±1.35 and 7.27±1.39 mm (P=0.662) under photopic illumination, respectively. However PDs were lower in IFIS under all illumination degrees, no significant difference was detected between groups.

CONCLUSION

IFIS is a significant clinical syndrome with an increased intraoperative/postoperative complication ratio. The prediction of this syndrome is important because of prevention required precautions against possible complications. There is no association between IFIS and preoperative PD.

Atropine in topical formulations for the management of anterior and posterior segment ocular diseases

INTRODUCTION

Atropine is an old-known drug which is gaining increasing attention due to the myriad of therapeutic effects it may trigger on eye structures. Nevertheless, novel applications may require more adequate topical formulations.

AREAS COVERED

This review aims to gather the existing knowledge about atropine and its clinical applications in the ophthalmological field when administered topically. Atropine ocular pharmacokinetics is paid a special attention, including recent evidences of the capability of the drug to access to the posterior segment. Ocular bioavailability and systemic bioavailability are counterbalanced. Finally, limitations of traditional dosage forms and potential advantages of under investigation delivery systems are analyzed.

EXPERT OPINION

Mydriasis and cyclopegia have been widely exploited for eye examination, management of anterior segment diseases, and more recently as antidotes of chemical weapons. Improved knowledge on drug receptors and related pathways explains atropine repositioning as an outstanding tool to prevent myopia. The ease with which atropine penetrates ocular tissues is a double edged sword, that is, while it ensures therapeutic levels in the posterior segment, the unspecific distribution causes a wide variety of untoward effects. The design of formulations that can selectively deliver atropine to the target tissue for each specific application is an urgent unmet need.

A narrative review of intraoperative floppy iris syndrome: an update 2020

Intraoperative floppy iris syndrome (IFIS) is characterized by intraoperative floppiness or billowing of the iris, progressive miosis, and iris prolapse through the surgical wounds. It was originally reported about fifteen years ago, which was later identified to be closely associated with tamsulosin, the most commonly used α1 adrenoceptor antagonist for benign prostatic hyperplasia (BPH). A variety of risk factors, including age, gender, hypertension, axial length of the eye, 5α-reductase inhibitors, other α adrenoceptor antagonist and neuromodulators, have been connected with IFIS. If IFIS occurs during phacoemulsification surgery, complications such as corneal endothelial loss, iris trauma, posterior capsule rupture (PCR), high intraocular pressure and vitreous loss are significantly increased. Therefore, preoperative evaluation of high-risk patients and appropriate intraoperative intervention is crucial to avoid severe complications. This review summarizes the pathogenesis and clinical features of classic IFIS, and provides some clinical pearls to ophthalmologists that may help identify, prevent or reduce IFIS associated complications. Additionally, from the perspective of clinical occurrence of IFIS, there are some recommendations for urologists as well. In conclusion, both ophthalmologists and urologists should be aware of this special clinical situation and communicate with each other about their own fields. A multidisciplinary interaction is of importance to simplify potentially complicated clinical issues.

Reaction-Based Ratiometric and Colorimetric Chemosensor for Bioimaging of Biosulfite in Live Cells, Zebrafish, and Food Samples

In this work, a reaction-based ratiometric and colorimetric sensor was designed and synthesized for probing bisulfite (HSO₃^-) by coupling coumarin (CM) with barbituric (BA) moiety. Further tests have shown that CM-BA has high selectivity and sensitivity for the recognition of HSO₃^-, which can be applied for the detection of HSO₃^- in environmental and biological systems very effectively. The fluorescence intensity ratios (F₄₆₂/F₅₆₈) exhibited an outstanding HSO₃^--dependent response with ultrafast response time (within 20 s) and a lower detection limit (105 nM). Meanwhile, the color of the CM-BA solution changed from green to colorless during the recognition process, and its fluorescence changed from green to blue. The mechanism of response is confirmed by the density functional theory (DFT) model. In summary, CM-BA has demonstrated low toxicity and good permeability, which can be applied for imaging HSO₃^- in cells and zebrafish safely and effectively. Besides, this novel sensor CM-BA successfully realized the quantification of the concentration of HSO₃^- in paper strips and food samples.

Intraoperative Floppy Iris Syndrome: Updated Perspectives

Almost fifteen years since its initial description, intraoperative floppy iris syndrome (IFIS) during phacoemulsification surgery remains a challenge for cataract surgeons in all its key aspects that include the stratification of the preoperative risk, preoperative prophylaxis treatment, surgery design and intraoperative management. Since its original association with tamsulosin intake, IFIS has been positively correlated with a plethora of risk factors which include: gender, age, hypertension, other a1-adrenergic receptor antagonists, finasteride, angiotensin II receptor inhibitors, benzodiazepines, antipsychotics, hypertension drugs and decreased dilated pupil diameter. The assessment and stratification of the preoperative risk is pivotal in screening patients prone to develop IFIS. For these patients, it is essential that preoperative prophylaxis, employment of necessary measures and surgical technique modifications are considered. A multidisciplinary approach of IFIS is a mandate, thus ophthalmologists, urologists and sometimes other specialties should cooperate to “educate” each other about the risks of their respective fields. They both must be aware of the joint statement on IFIS by the American Academy of Ophthalmology and the American Society of Cataract and Refractive Surgery which suggests either the initiation of tamsulosin after phacoemulsification or the use of a non-selective a1-ARA for benign prostatic hyperplasia treatment. In conclusion, awareness of the risk factors associated with IFIS and their detailed preoperative documentation is crucial in addressing IFIS. The lack of such an awareness can turn a routine, uneventful surgery into one with significant visual morbidity.

Drop-free approaches for cataract surgery

PURPOSE OF REVIEW

Routine prophylaxis for adverse events following cataract surgery is evolving. Prior reliance on topical eyedrop instillation by patients is giving way to surgeon directed injections at the time of cataract surgery. The benefit of this new approach is assured delivery of drugs in standardized doses which should optimize the healing process and reduce the incidence of untoward events with higher confidence.

RECENT FINDINGS

Adoption rates of intracameral antibiotic injection amongst European and American cataract surgeons is increasing. Techniques to inject periocular corticosteroid for routine inflammation prophylaxis are also in development. In combination with intraoperative pharmacologic dilation, a drop-free modality can be achieved.

SUMMARY

Intraoperative injections offer the patient and surgeon assured drug delivery and hold promise to avoid the pitfalls of patient adherence, incorrect topical instillation, and topical drop-associated corneal issues.