The floppy iris syndrome - what urologists and ophthalmologists need to know

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.

Impact of Nonselective and Selective α-1 Adrenergic Blockers on the Sedative Efficacy of Dexmedetomidine in Urologic Surgery: A Prospective, Observational Study

BACKGROUND This study aimed to compare the impact of a-1 adrenergic blockers - nonselective (alfuzosin, doxazosin, and terazosin) and selective (silodosin and tamsulosin) - on the sedative effects of the alpha-2 adrenergic agonist dexmedetomidine (DMT) in patients undergoing urologic surgery. The primary outcome was the sedative effect of DMT as determined by the bispectral index (BIS) and Modified Observer's Assessment of Alertness/Sedation (MOAA/S) scale scores. MATERIAL AND METHODS One hundred eighteen patients undergoing elective urologic surgery with spinal anesthesia were recruited. Patients were assigned based on their medication status to group N (no medication; n=33), group NS (nonselective alpha-1 blocker; n=27), or group S (selective alpha-1 blocker; n=58). Mean blood pressure (MBP), heart rate (HR), oxygen saturation (SpO₂), BIS, and MOAA/S scale scores were recorded at 5-minute (min) intervals after DMT administration. RESULTS Group NS had significantly higher BIS scores than groups N and S at 25 min (P=0.045) and 30 min (P=0.030) after DMT administration, indicating lower sedation levels. MBP significantly differed between the 3 groups at all time points, with group N experiencing a lower MBP than groups NS and S. No significant differences were found between the groups in MOAA/S scale scores, SpO₂, or HR. CONCLUSIONS Nonselective alpha-1 adrenergic blockers can reduce the sedative effects of DMT. Consequently, there may be a need for individualized anesthesia management considering the specific subtype of alpha-1 adrenergic blocker medication.

Floppy iris syndrome associated with specific medication intake: A narrative review

Intraoperative floppy iris syndrome (IFIS) is a cataract surgery complication that remains a challenge for eye surgeons. It is caused by the antagonism of alfa-1-adrenergic receptors within the dilator muscle of the iris, thus preventing the iris from dilation during a cataract surgery. The long-term blocking alfa-1 adrenergic receptors by the chronic use of a number of systemic medications may lead to permanent anatomical atrophy of the dilator muscle of the iris. The most common drugs associated with the development of IFIS are tamsulosin and other alpha-1 adrenergic receptor antagonists prescribed to patients with low urinary tract symptoms (LUTS). There are other systemic medications that have been reported to have increased risk for IFIS. It is crucial for the ophthalmologist to identify the high-risk patients prone to develop IFIS. Its presence may complicate the course of cataract surgery, ultimately negatively affecting visual outcome. Cataract surgery should be performed by an experienced eye surgeon using alternative pharmacological and surgical techniques. Interdisciplinary cooperation is essential to mitigate potential complications. Patients should be informed by their physicians about the need to report a medication history to their eye specialists, especially before cataract surgery.

[Intraoperative floppy iris syndrom (IFIS) associated with tamsulosin]

BACKGROUND

Tamsulosin is one of the most commonly prescribed alpha-1A antagonists for the treatment of benign prostatic syndrome (BPS). Patients treated with tamsulosin often develop intraoperative floppy iris syndrome (IFIS) during cataract surgery. This leads to increasing miosis and an undulating iris, which increases the risk of complications significantly and can cause permanent damage.

AIM OF THE WORK

The aim is to raise awareness for the effects of tamsulosin intake before cataract surgery.

MATERIAL AND METHODS

We conducted a critical review of publications on the association of IFIS in cataract surgery with alpha-receptor blockers.

RESULTS AND DISCUSSION

Tamsulosin has a risk of complications of up to 80 %, whereas doxazosin and alfuzosin only have a 15-20 % chance of complications. Tamsulosin therefore represents a significant risk factor for permanent secondary damage after cataract surgery. Even after discontinuing tamsulosin, IFIS was still observed after up to 3 years. Nevertheless, pausing of tamsulosin intake is recommended. An alternative preparation should therefore be preferred in patients who have not yet had cataract surgery. If patients are already pseudophakic, tamsulosin can be given without concern.

Current and Emerging Classes of Pharmacological Agents for the Management of Hypertension

Cardiovascular disease accounts for more than 17 million deaths globally every year, of which complications of hypertension account for 9.4 million deaths worldwide. Early detection and management of hypertension can prevent costly interventions, including dialysis and cardiac surgery. Non-pharmacological approaches for managing hypertension commonly involve lifestyle modification, including exercise and dietary regulations such as reducing salt and fluid intake; however, a majority of patients will eventually require antihypertensive medications. In 2020, the International Society of Hypertension published worldwide guidelines in its efforts to reduce the global prevalence of raised blood pressure (BP) in adults aged 18 years or over. Currently, several classes of medications are used to control hypertension, either as mono- or combination therapy depending on the disease severity. These drug classes include those that target the renin-angiotensin-aldosterone system (RAAS) and adrenergic receptors, calcium channel blockers, diuretics and vasodilators. While some of these classes of medications have shown significant benefits in controlling BP and reducing cardiovascular mortality, the prevalence of hypertension remains high. Significant efforts have been made in developing new classes of drugs that lower BP; these medications exert their therapeutic benefits through different pathways and mechanism of actions. With several of these emerging classes in phase III clinical trials, it is hoped that the discovery of these novel therapeutic avenues will aid in reducing the global burden of hypertension.

Silodosin as a predisposing factor of intraoperative floppy iris syndrome (IFIS): an observational propensity score-matching cohort study

PURPOSE

To evaluate the correlation between silodosin and intraoperative floppy iris syndrome (IFIS) and compare it with other a1-adrenergic receptor antagonists (a1-ARAs) and other factors predisposing to IFIS.

METHODS

From the patients who underwent phacoemulsification between 2014 and 2020, we identified all patients who, during their preoperative assessment, reported an a1-ARAs intake (exposed group). These patients were matched utilizing a propensity score matching analysis with an otherwise homogenous group of patients (control group) based on demographics and systemic/ocular comorbidities.

RESULTS

A total of 350 patients were included in each group. In the exposed group, 177 (50.6%) patients were exposed to tamsulosin, 105 (30%) to alfuzosin, 43 (12.2%) to silodosin. Regarding IFIS, it was observed in 21.5% of patients on tamsulosin (38/177), 11.4% on alfuzosin (12/105), 37.2% on silodosin (16/43), and 3.4% in the controlled group (12/350). In a multiple regression model analysis, the only two factors significantly associated with IFIS development were silodosin and tamsulosin yielding an adjusted odds ratio of 8.471 (95%CI 4.005-17.920) and 3.803 (95%CI 2.231-6.485), respectively.

CONCLUSION

Silodosin has been demonstrated as a predisposing factor, strongly correlated with IFIS development. These results should increase cataract surgeons' awareness to assess their patients preoperatively for exposure to silodosin carefully and employ the appropriate prophylactic measures to ameliorate the impact of silodosin intake on the surgical outcome.

Ocular Side Effects of Common Systemic Medications and Systemic Side Effects of Ocular Medications

When prescribing medications, it is important to consider the ocular side effects of common systemic therapy as well as potential systemic side effects of ocular medications. Although not an exhaustive list of medications/classes of medications, this article does include many commonly used drugs and also provides information on some topical therapies commonly used by ophthalmologists. These ocular medications may result in systemic effects and/or alter patients' management of systemic conditions.

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.

Ten years of intraoperative floppy iris syndrome in the era of α-blockers

Introduction

The use of alpha-1 receptor antagonists in the treatment of benign prostatic hyperplasia (BPH) has created a problem in ophthalmic surgery, the so-called intraoperative floppy iris syndrome (IFIS). This consists of a billowing iris, insufficient pupillary dilation with progressive intraoperative miosis, and protrusion of iris tissue through the tunnel and side port incision that are made for access to the anterior chamber during surgery. IFIS presents particular difficulties in cataract surgery which is carried out through the pupil with manipulations in the immediate vicinity of the iris. The complications range from poor visibility of the operative field to iris damage with the surgical instruments and to rupture of the posterior capsule, with loss of lens material into the vitreous body.

Material and methods

A comprehensive literature review was performed using MEDLINE with MeSH terms and keywords 'benign prostatic hyperplasia', 'intraoperative floppy iris syndrome', 'adrenergic alpha-antagonist' and 'cataract surgery'. In addition, reference lists from identified publications were reviewed to identify reports and studies of interest from 2001 to 2017.

Results

The A total of 95% of experienced ophthalmologic surgeons reported that systematic treatment with tamsulosin represents a challenging surgical condition increasing the risk of complications. Alpha-blockers are commonly prescribed, with 1,079,505 packages of tamsulosin prescribed each month in 2014 in Austria. Dose modification may be one way to reduce the risk of IFIS. A lower incidence of IFIS was reported in patients on tamsulosin in Japan, but the recommended dosage was lower than that used in Europe and the US (0.2 mg vs. 0.4 mg).

Conclusions

We showed that not all patients taking tamsulosin experience IFIS. Moreover, larger investigations with a prospective design are needed, including studies to monitor the pre- and post-therapeutic ophthalmologic changes under tamsulosin, as well as urodynamic improvements resulting from this therapy.