Clinical features, complications, and incidence of intraoperative floppy iris syndrome in patients taking tamsulosin

A metabolomics study: Could plasma metabolites be a guide for the prevention of tamsulosin side effects?

BACKGROUND

The understanding of precision medicine, which aims for high efficacy and low toxicity in treatments, has gained more importance with omics technologies. In this study, it was aimed to reach new suggestions for low-toxicity treatment by clarifying the relationship between tamsulosin side effects and metabolome profiles.

MATERIALS AND METHODS

Plasma samples of control and tamsulosin-treated rats were analyzed by LC-Q-TOF/MS/MS. MS/MS data was processed in XCMS software for the identification of metabolite and metabolic pathway analysis. Data were classified with MATLAB 2019b for multivariate data analysis. 34m/z values were found to be significantly different between the drug and control groups (P≤0.01 and fold analysis≥1.5) and identified by comparing METLIN and HMDB databases.

RESULTS

According to multivariate data analysis, α-Linolenic Acid, Thiamine, Retinoic acid, 1.25-Dihydroxyvitamin D3-26.23-Lactone, L-Glutamine, L-Serine, Retinaldehyde, Sphingosine 1-phosphate, L-Lysine, 23S.25-Dihydroxyvitamin D3, Sphinganine, L-Cysteine, Uridine 5'-diphosphate, Calcidiol, L-Tryptophan, L-Alanine levels changed significantly compared to the control group. Differences in the metabolisms of Retinol, Sphingolipid, Alanine-Aspartate-Glutamate, Glutathione, Fatty Acid, Tryptophan, and biosynthesis of Aminoacyl-tRNA, and Unsaturated Fatty Acid have been successfully demonstrated by metabolic pathway analysis. According to our study, vitamin A and D supplements can be recommended to prevent side effects such as asthenia, rhinitis, nasal congestion, dizziness and IFIS in the treatment of tamsulosin. Alteration of aminoacyl-tRNA biosynthesis and sphingolipid metabolism pathways during tamsulosin treatment is effective in the occurrence of nasal congestion.

CONCLUSIONS

Our study provides important information for tamsulosin therapy with high efficacy and low side effects in precision medicine.

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.

Risk of intraoperative floppy iris syndrome among selective alpha-1 blockers—A consistency model of 6,488 cases

Selective α1-blockers are commonly administered to patients with lower urinary tract syndrome and benign prostatic hyperplasia, but may increase the risk of intraoperative floppy iris syndrome (IFIS). The purpose of this study aimed to clarify the risk of IFIS among various selective α1-blockers. Four databases were searched for prospective studies comparing alpha-1-antagonists. Data were pooled using the consistency model, and used risk ratio (RR) and mean difference (MD) for IFIS and pupil diameter, respectively. This study finally included 25 prospective comparative studies. Based on 51 direct comparisons with 6488 cases, risks of IFIS in patients who received tamsulosin [RR, 13.85; 95% confidence interval (CI): 7.34 to 26.11], terazosin (RR, 8.94; 95% CI 2.88 to 27.74), alfuzosin (RR, 7.73; 95% CI: 3.05 to 19.62), and doxazosin (RR, 3.88; 95% CI: 1.13 to 13.28) were significantly higher than those did not receive α1-antagonists. Based on 11 direct comparisons with 564 cases, as compared to no α1-antagonists, patients who received tamsulosin (MD, −0.36; 95% CI: −0.71 to −0.01) and alfuzosin (MD, −0.34; 95% CI: −0.62 to −0.07) showed smaller pupil diameter under mesopic light levels, while those received silodosin did not show significantly smaller mesopic pupil diameter than people without α1-antagonists. IFIS seems to be inevitable with the usage of α1-antagonists, and tamsulosin needs to be cautious due to the significantly higher risk of severe IFIS. With regard to silodosin, there is no strong evidence to support the uses of italthough it does not significantly decrease mesopic pupil diameter.

Intraoperative Floppy Iris Syndrome Induced by Tamsulosin: The Risk and Preventive Strategies

Tamsulosin is an antagonist of a subtype-specific alpha-1A- and alpha-1D-adrenoceptor (AR) that is expressed in the prostate gland, urethra, and bladder. Several reports have shown a possible relationship between ophthalmologic adverse effects and the use of alpha-1-receptor medicines, including tamsulosin. This descriptive review evaluates the intraoperative floppy iris syndrome (IFIS) associated with tamsulosin. A search of the Medline and PubMed databases was conducted to identify control trials, case reports, and observational examinations published in English. The publication dates were restricted (January 1, 2000, to January 1, 2020). Keywords (tamsulosin, alpha-blocker, ocular, eye, adverse reaction, and IFIS) were used in the searches. The searches identified 66 studies including in vitro or in vivo studies, trials, and observational studies. Twenty-two (33.33%) studies were articles citing tamsulosin and IFIS as having confirmed potential risk to ocular safety. The results of this review, including a comprehensive summary of published research on tamsulosin use in different populations, have identified several articles showing associations between tamsulosin and IFIS that merit further investigation. Suspending of potential causative pharmacological treatment of IFIS before ocular surgery including tamsulosin, proper identification of at-risk patients, preoperative prophylaxis treatments, and surgical technique modifications clearly can mitigate the anticipated risk of IFIS induced by tamsulosin.

Modified Surgical Techniques for Managing Intraoperative Floppy Iris Syndrome

Purpose. To report a modified surgical strategy in the management of intraoperative floppy iris syndrome-associated iris prolapse. Methods. Prolapsed iris is left as is and a new corneal incision near the original wound but at a different site is created. Depending on the location of the original incision and the surgeon's preference, this additional incision can be used as a new port for phacoemulsification tip or can be the new site for the iris to securely prolapse, allowing for the surgery to proceed safely. Results. We present 2 cases of iris prolapse and inadequate pupil dilation in patients with IFIS. Along with our modified technique, additional iris retractors were placed to increase the workspace for the phacoemulsification tip. The cataract surgery was performed successfully without further complications in both cases. Conclusion. This surgical technique could be an adjunct to allow the surgeons to expand the armamentarium for the management of IFIS-associated iris prolapse.

Intraoperative floppy iris syndrome in Indian population: a prospective study on incidence, risk factors, and impact on operative performance

PURPOSE

The purpose of this study was to evaluate the incidence, risk factors, and impact of intraoperative floppy iris syndrome (IFIS) on surgical performance.

MATERIALS AND METHODS

Consecutive cataract surgeries from October 2010 to Feb 2011 (1003 eyes, 980 patients; 568 males, 412 females) were analyzed prospectively. Operating surgeon, masked about medication history, noted the intraoperative details. Cases were identified as IFIS or non-IFIS. Multivariate analysis was performed to find risk factors for IFIS.

RESULTS

Prevalence of tamsulosin use among men undergoing cataract surgery was 7.0% (41) with incidence of IFIS 4.78% (48). On multivariate analysis, hypertension (OR: 3.2, 95% confidence interval, 95% CI: 1.39-6.57; P = 0.005), use of tamsulosin (OR: 133.32, 95% CI: 50.43-352.48; P < 0.0001), or alfuzosin (OR: 9.36, 95% CI: 2.34-37.50; P = 0.002) were the factors associated with IFIS. Among men taking tamsulosin (n = 41) and alfuzosin (n = 28), 68.3% and 16.6% developed IFIS, respectively. In subgroup analysis of men on tamsulosin, no factor added to the risk posed by tamsulosin. Seventeen of 944 eyes not exposed to any drug had IFIS (0.018%). On subgroup analysis, only risk factor for IFIS was hypertension (OR: 4.67, 95% CI: 1.63-13.35; P = 0.002). Of 48 IFIS eyes, the surgeon observed increased difficulty in 57.1% (21) and additional measures were required in 9 eyes. Mean operative time was increased in IFIS eyes (11.68 ± 3.46 vs. 10.01 ± 0.22 min; P = 0.001). Surgical outcome was good in all cases.

CONCLUSION

The prevalence of tamsulosin intake and IFIS incidence is higher in India. Current tamsulosin/alfuzosin use and hypertension are important risk factors. IFIS makes the surgery more difficult, significantly prolongs the operative time, and predisposes for other intraoperative complications. However, with appropriate management, final operative outcome is not affected.

Risk factors for intraoperative floppy iris syndrome: a prospective study

PurposeTo evaluate risk factors for intraoperative floppy iris syndrome (IFIS) in patients undergoing phacoemulsification.MethodsParticipants in the study were 1274 consecutive patients, who underwent routine phacoemulsification cataract surgery. The following data were recorded and evaluated as possible risk factors: ophthalmological conditions, axial length of the eye, sociodemographic features, clinical data (hypertension and diabetes mellitus), medications being taken at the time of surgery, and duration of their intake. Cases were characterized intraoperatively as IFIS and non-IFIS. Univariate and multivariate logistic regression analysis were performed.ResultsIFIS was observed in 63/1274 eyes (4.9%, 95% CI: 3.9-6.7%). Current use of tamsulosin, alfuzosin, terazosin, benzodiazepines, quetiapine, and finasteride, as well as hypertension, were all independently associated with IFIS. Significant associations were noted for male sex, rivastigmine, and short axial length, which did not reach significance at the multivariate analysis. Duration of α-blockers intake was not found to be associated with IFIS.ConclusionApart from the well-established associations with α-blockers, this prospective study points to benzodiazepines, quetiapine, finasteride, and hypertension as potential risk factors for IFIS. Short axial length and rivastigmine were significantly associated with IFIS only at the univariate analysis.

Modified corneal incisions in intraoperative floppy iris syndrome (IFIS)-prone patients

BACKGROUND

We aimed to report a simple technique that involves modified anterior (to the limbus) elongated corneal incisions in order to reduce the incidence and severity of intraoperative floppy iris syndrome (IFIS) and related complications.

METHODS

This was a retrospective study of phacoemulsification cataract surgeries performed by a single surgeon on patients receiving tamsulosin or alfuzosin between 1 January 2009 and 31 July 2012 at Meir Medical Center, Kfar-Sava, Israel. We recorded preoperative gender, age, α-antagonist medication, coexisting pseudoexfoliation (PXF), and intraoperative use of ophthalmic viscosurgical devices (OVDs), pupil size, complications, IFIS grading and the need for additional operative strategies to manage IFIS. Elongated corneal incisions were performed approximately 1 mm anterior to the limbus.

RESULTS

Ninety-three eyes of 81 men were included. Mean age was 76.5 years (range 55 to 96 years). Forty-seven eyes (40 patients) had documented use of alfuzosin and 45 eyes (40 patients) of tamsulosin. One patient received both. The overall rate of IFIS was 22.6 % (n = 21). Eyes of patients who were treated with alfuzosin had a milder grading (p < 0.001) and an overall lower percentage of IFIS compared to tamsulosin (4.26 % versus 42.22 % respectively, p < 0.001). No additional strategies were used to manage IFIS during surgery. No intraoperative complications occurred.

CONCLUSION

Anterior elongated incisions are simple and efficient in preventing IFIS, exempting the surgeon from the use of additional expensive devices or materials in most cases. They do not limit the surgeon to one strategy, and therefore, if necessary, another may be applied at any given time.

The differential pupillary response to 2.5% phenylephrine in patients taking tamsulosin

PURPOSE

To determine if a pharmacological test could be developed to determine iris dilator dysfunction in patients taking tamsulosin.

METHODS

Patients taking tamsulosin and controls were recruited from the Urology and Ophthalmology clinics at the Montefiore Medical Center. The patient's right eye (OD) was dilated with phenylephrine hydrochloride 2.5% and tropicamide 1%. The patient's left eye (OS) was dilated with tropicamide 1% alone. Forty minutes after dilation, pupillary diameter was measured in both eyes.

RESULTS

Thirty-eight tamsulosin subjects and 43 controls met the inclusion criteria for the study. The tamsulosin-treated patients dilated less with phenylephrine than controls (0.61±0.4 vs. 1.10±0.45 mm, respectively P<0.001). Receiver operating characteristic curves comparing maximal pupillary dilation versus differential pupillary dilation in tamsulosin patients relative to controls shows a greater area under the curve for differential dilation (0.8 vs. 0.6, respectively). A correlation between smooth muscle dysfunction and length of time on tamsulosin was observed. Patients using tamsulosin for <1 month had an average OD-OS difference of 0.85±0.5 mm. Patients who were on tamsulosin for >1 month had an average OD-OS difference of 0.52±0.32 mm (P<0.01, Mann-Whitney).

CONCLUSION

Patients treated with tamsulosin demonstrated a significantly decreased iris dilatory response to the selective adrenergic effects of phenylephrine compared to controls. Additionally, it appears that longer duration of exposure to tamsulosin increases the likelihood of dilator dysfunction.

Sub-Tenon injection of 2% lidocaine prevents intra-operative floppy iris syndrome (IFIS) in male patients taking oral α-adrenergic antagonists

PURPOSE

  To compare 2% sub-Tenon and 1% intra-cameral lidocaine for cataract surgery in relation to the incidence and severity of IFIS. Prospective randomized clinical study.

METHODS

  From 81 eligible, we included 71 men aged from 59 to 90 years (mean 76.5 ± 6.8) undergoing routine cataract surgery and taking oral α-adrenergic antagonists, for urological reasons, for more than 1 year. Following randomization 34 men, aged from 62 to 90 years (mean 77.4 ± 8.1) received sub-Tenon injection of 2.5 ml of 2% lidocaine and the remaining 37 men aged from 59 to 89 years (mean 75.2 ± 7.2) received 1% preservative free intra-cameral lidocaine. Outcome measures were the incidence of IFIS, severity of intra-operative pupillary constriction and iris prolapse.

RESULTS

  Intra-operative floppy iris syndrome (IFIS) was noted in 3 of 34 patients (8.8%) receiving sub-Tenon lidocaine and in 18 of 37 patients (48.6%) receiving intra-cameral lidocaine (p = 0.00). Severe IFIS was observed only in 3 of 37 patients (8.1%) receiving intra-cameral lidocaine. Pupil diameter at the end of surgery was 4.37 ± 1.07 mm in the sub-Tenon lidocaine group and 4.02 ± 1.06 mm in the intra-cameral lidocaine group (p = 0.00). Iris prolapse was noted in two cases in the sub-Tenon lidocaine group and in 10 cases in the intra-cameral lidocaine group (p = 0.00). Twenty-five patients were receiving tamsulosin. The incidence of IFIS in tamsulosin subgroup was 76.9% (10 of 13 patients) in the intra-cameral lidocaine group and 16.6% (2 of 12 patients) in the sub-Tenon lidocaine group (p = 0.00).

CONCLUSION

  Sub-Tenon lidocaine reduces significantly the incidence of IFIS in patients taking oral α-adrenergic inhibitors as compared with intra-cameral lidocaine.

Corneal endothelial cell changes after cataract surgery in patients on systemic sympathetic α-1a antagonist medication (tamsulosin)

PURPOSE

  The purpose of this study was to assess the incidence of intraoperative floppy iris syndrome (IFIS) and the morphology of the corneal endothelium after cataract extraction in Caucasian male patients exposed to the α-1a adrenergic receptor antagonist tamsulosin.

METHODS

  In a clinical prospective study, 23 male patients (23 eyes) treated with tamsulosin due to benign prostatic hyperplasia and 25 male patients (25 eyes) with no tamsulosin treatment had cataract surgery. The divide-and-conquer technique was used with the Infinity OZil(®) machine. A combination of Healon and Healon5 was used in all patients, but the use of additional Vision Blue, iris retractors or intracameral phenylephrine in the tamsulosin group was at the discretion of the surgeon. The endothelial cell density, variation in endothelial cell size (CV), percentage of hexagonal cells and central corneal thickness (CCT) were recorded at baseline and at 3 months postoperatively.

RESULTS

  In the tamsulosin-treated group, 19 of 23 eyes (83%) developed IFIS, compared with no IFIS in the control group. Compared with the control group, the tamsulosin group showed significantly less dilatation at the start of the operation, significant miosis during surgery and significantly greater corneal endothelial cell loss 3 months postoperatively (12% versus 3%; p< 0.001).

CONCLUSION

  Intraoperative floppy iris syndrome during cataract surgery is significantly associated with tamsulosin-treated male patients. Patients on tamsulosin showed less preoperative dilatation, significant miosis during surgery, and had significantly greater postoperative endothelial cell loss compared with nontreated patients despite recommended precautions.

Intraoperative floppy iris and prevalence of intraoperative complications: results from ophthalmic surgery outcomes database

PURPOSE

To estimate the prevalence of untoward events during cataract surgery with the use of pupillary expansion devices and intraoperative floppy iris (IFIS).

DESIGN

Retrospective analysis of 4923 cataract surgery cases from the Veterans Affairs Ophthalmic Surgical Outcomes Data Project.

METHODS

Outcomes from 5 Veterans Affairs medical centers were analyzed, including use of alpha-blockers (both selective and nonselective), IFIS, intraoperative iris trauma, intraoperative iris prolapse, posterior capsular tear, anterior capsule tear, intraoperative vitreous prolapse, and use of pupillary expansion devices. P values were calculated using the χ(2) test.

RESULTS

A total of 1254 patients (25.5%) took alpha-blockers preoperatively (selective, 587; nonselective, 627; both, 40). Of these 1254 patients, 428 patients (34.1%) had documented IFIS. However, 75.2% of patients with IFIS (428/569) had taken alpha-blockers preoperatively (P < .00001). A total of 430 patients (8.7%) had a pupillary expansion device used during their cataract surgery, of which 186 patients (43.4%) had IFIS (P < .0001). Eighty-six patients with IFIS had at least 1 intraoperative complication and 39 patients with IFIS had more than 1 intraoperative complication (P < .001).

CONCLUSIONS

The use of either selective or nonselective alpha-antagonists preoperatively demonstrated a significant risk of IFIS. Nonselective alpha-antagonists caused IFIS at a higher prevalence than previously reported. This study did demonstrate statistically significant increased odds of surgical complications in patients with IFIS vs those without IFIS in all groups (those taking selective and nonselective alpha-antagonists and also those not taking medications).

Korean patients taking α1-adrenergic receptor antagonists show lower incidence of intraoperative floppy iris syndrome than western patients

PURPOSE

To evaluate the incidence and clinical manifestations of intraoperative floppy iris syndrome (IFIS) according to iris alterations in Korean patients taking α1-adrenergic receptor antagonists (α1-ARAs).

METHODS

This is a prospective observational study. Two surgeons performed cataract surgery in 758 eyes of 596 patients over a period of 12 months. Past medical history was reviewed, especially whether patients had been taking systemic α1-ARAs. Ultrasound biomicroscopy was performed to measure the iris thickness of the dilator muscle region (DMR) at half the distance between the scleral spur and the pupillary margin. Pupil diameter was measured and the occurrence of IFIS was recorded. Measurements of the α1-ARA group were compared with those of a control group matched for age and sex.

RESULTS

IFIS occurred only in six eyes of four patients on systemic α1-ARA medications (0.8%). Pupil diameter in the α1-ARA medication group and the control group was not significantly different. The difference in mean DMR thickness in patients taking an α1-ARA and in the control group was also not statistically significant (p=0.641). However, within the α1-ARA population, the DMR thickness of IFIS cases was significantly lower than that of non-IFIS cases (p=0.013) CONCLUSIONS: The overall incidence of IFIS was far lower in Korean patients than that reported for western patients. IFIS patients taking α1-ARAs showed significantly greater iris DMR thinning than non-IFIS patients taking α1-ARAs. Our findings indicate that the interaction between α1-ARAs and melanin, which results in iris DMR atrophy and IFIS, is less strong in Korean patients (with dark irises) than western patients.

Comparing the efficacy of mydriatic cocktail-soaked sponge and conventional pupil dilation in patients using tamsulosin - a randomized controlled trial

BACKGROUND

A strong association exists between the use of tamsulosin and the occurance of intraoperative floppy iris syndrome. Several methods were advocated to overcome the progressive intraopertive miosis.Our purpose was to investigate the effect of a mydriatic-cocktail soaked cellulose sponge on perioperative pupil diameter in tamsulosin-treated patients undergoing elective cataract surgery.

METHODS

Patients using tamsulosin were dilated either with mydriatic-cocktail soaked sponge (group 1) or with conventional eyedrop regimen (group 2). Control patients not taking any α1 adrenergic receptor inhibtors were also dilated with mydriatic sponge (group 3).In all groups oxybuprocain 0.4%, cocain 4%, tropicamide 1%, phenylephrine 10%, diclophenac 0.1% along with chloramphenicol 0.5% were used preoperatively.Pupil diameter (mm) was measured preoperatively, after nucleus delivery, and before IOL implantation. Adverse effects associated with the use of sponge, minor and major intraoperative complications, the use of iris retractors and operation time were recorded.Differences in general between groups were analyzed with a one way analysis of variance (ANOVA); differences between groups in proportions were assessed by Fisher's exact test.

RESULTS

Mean pupil diameter (mm) was preopertively: 7.52 ± 1.21, 7.30 ± 1.55 and 7.99 ± 0.96 (ANOVA: p = 0.079); after nucleus delivery: 6 ± 1.20, 6.29 ± 1.12 and 6.52 ± 0.81 (ANOVA: p = 0.123); before IOL implantation: 5.46 ± 1.06, 5.83 ± 1.09 and 6.17 ± 0.89 (ANOVA: p = 0.0291).No adverse effect related to sponge use was detected. Frequency of minor complications, and iris hook use was similar in the two tamsulosin treated group. Operation time did not differ significantly in the three groups.

CONCLUSION

We have found that using a mydriatic cocktail-soaked wick - an alternative way to achieve intraoperative mydriasis for cataract surgery - was as effective and safe as the conventional repeated eyedrops regiment for tamsulosin treated patients.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN37834752.

Urologic medications and ophthalmologic side effects: a review

Commonly prescribed urologic medications can have significant ophthalmologic side effects. The existing information can be conflicting. We looked at alpha-blockers and intraoperative floppy iris syndrome (IFIS), phosphodiesterase type 5 (PDE5) inhibitors and non-arteritic ischemic optic neuropathy (NAION) and lastly anticholinergic medications and glaucoma. There is no conclusive scientific data on what to do if the risk of urinary retention is low to moderate, however, we recommend that patients having cataract surgery should stop alpha-blocker medications preoperatively. If there is a high risk of urinary retention, the alpha-blocker should not be withheld, with the active involvement of the ophthalmologist. The role of using 5 alpha-reductase inhibitors (5ARIs) can be considered. There is no convincing evidence that PDE5 inhibitors cause non-arteritic anterior ischemic optic neuropathy (NAION), but patients should be advised of the possible risk of visual loss, especially in patients with risk factors of ischemic heart disease. Acute angle closure glaucoma (AACG or closed angle glaucoma) is very rarely caused by anticholinergic medications in patients with narrow angle anterior eye chambers. However, these medications are safe in patients with open angle glaucoma or treated closed angle glaucoma. Urologists should inquire about the patient's glaucoma history from his/her ophthalmologist before starting an anticholinergic medication.

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

INTRODUCTION

Benign prostatic hyperplasia (BPH) and cataract formation are common in older people. Medical management of symptomatic BPH is often preferred to surgical treatment as surgery increases the risk of morbidities, whereas, surgery is the main form of treatment to restore sight in patient with cataract. The clinical treatment of BPH is either alpha-1 adrenergic antagonist alone or combination of alpha reductase inhibitor and alpha adrenergic receptor (AR) antagonist. There are four alpha-AR antagonists currently available to treat BPH. The uroselective alpha-blocker tamsulosin is the most commonly used drug among all. Studies showed that the majority of the patients who develop intraoperative floppy iris syndrome (IFIS) were on tamsulosin. Women are more likely to develop cataract than men and some recent studies showed that tamsulosin is effective in treating female lower urinary tract symptoms and thereby can cause IFIS during cataract surgery.

EVIDENCE ACQUISITION

We performed a critical review of the published articles and abstracts on association of IFIS with alpha-blockers and other medications as well as other medical conditions.

EVIDENCE SYNTHESIS

Tamsulosin is the most common cause of formation of IFIS. However, not all patients given tamsulosin develop IFIS and cases have been reported without any tamsulosin treatment.

CONCLUSION

Tamsulosin is a recognized cause to impede mydriasis and lead to IFIS during cataract surgery. Urologist should collaborate with their ophthalmology colleagues and general practitioner during prescribing tamsulosin in patients with history of cataract or waiting for planned cataract surgery. The increasing life expectancy and growth of older people will increase the number of men and women who suffer from lower urinary tract symptoms as well as cataract. Therefore, further research and studies are required to properly understand the relation of alpha blockers and IFIS.

The effect of alpha antagonists on pupil dynamics: implications for the diagnosis of intraoperative floppy iris syndrome

PURPOSE

To assess pupil dynamics quantitatively in relation to the use of α1-adrenoceptor antagonists, which contribute to the features of intraoperative floppy iris syndrome, using a new, hand-held, digital pupillometer.

DESIGN

Prospective case-control study.

METHODS

We studied 15 and 25 patients administered tamsulosin and alfuzosin, respectively, as well as 25 control patients. Resting pupil diameter and subsequent contraction, latency, constriction velocity, and dilation velocity were recorded using an electronic pupillometer. All pupil measurements were performed before and after pharmacologic dilation.

RESULTS

In predilation pupillary measurements, we detected a significant decrease in maximum pupillary diameter by 0.50±0.19 mm (P=.011) and in the mean percentage of diameter reduction after stimulation (5.23±2.42%, P=.035) in the tamsulosin group. Alfuzosin also induced a significant decrease in maximum pupillary diameter (0.49±0.17 mm, P=.005). Constriction velocity was significantly reduced by 0.70±0.20 m/s (P=.001) in the tamsulosin group and by 0.54±0.18 m/s (P=.004) in the alfuzosin group. In terms of postdilation measurements, maximum and minimum pupil diameters were reduced significantly only in the tamsulosin group (by 1.09±0.31 mm [P=.001] and by 0.89±0.36 mm [P=.016], respectively).

CONCLUSIONS

We describe a reliable, accurate, and rapid method to acquire quantitative pupil measurements and identify the tendency for intraoperative floppy iris syndrome before cataract surgery after the use of alfuzosin and tamsulosin. This investigation also analyzed the similarities and differences induced by the 2 drugs in predilation and postdilation pupil dynamics, demonstrating that tamsulosin is more potent than alfuzosin in inducing intraoperative floppy iris syndrome.

Anterior-posterior asymmetry in iris mechanics measured by indentation

Indentation and histological analysis of the porcine iris were done to assess the relative stiffness of the anterior (stroma) and posterior (dilator and sphincter) layers. The dimensions of the constituent structures were documented histologically by staining with a monoclonal anti-human α-smooth muscle actin antibody to determine the location of the stroma, sphincter, and dilator. Intact porcine irides (4-8 h post-mortem) were bisected into two equal C-shaped halves to indent both surfaces. Indentation experiments were performed using a 1 mm cylindrical indenter tip. The load-displacement curve for each experiment was used to estimate effective instantaneous and equilibrium moduli for the anterior and posterior surfaces of the tissue. A total of 18 irides (9 pairs) with 3-5 indentations per iris surface was performed. The average thickness of the samples was 550 μm; the indentation depth was limited to 60-100 μm depending on the thickness of the sample at each point. Posterior surface indentation gave larger forces than anterior, with the resulting instantaneous modulus of 6.0 ± 0.6 kPa versus 4.0 ± 0.5 kPa (mean ± 95% CI, n = 45, p < 0.001) and equilibrium modulus of 4.4 ± 0.9 versus 2.3 ± 0.3 (p = 0.007). The stress-relaxation analysis revealed that the anterior surface had a shorter relaxation time (121.31 ± 6.84 s) than the posterior surface (210.61 ± 9.41 s, p = 0.03), perhaps due to the permeability of the stroma. Recognizing that our effective modulus calculations in this study did not account for heterogeneity, viscoelasticity, or poroelasticity, we conclude that the posterior components of the iris - dilator, pigment epithelium, and sphincter - are on average stiffer than the stroma and anterior border layer.

Intraoperative floppy iris syndrome (IFIS): a practical approach to medical and surgical considerations in cataract extractions

Intraoperative floppy iris syndrome (IFIS) during cataract surgery is characterized by iris fluttering, iris prolapse towards the incisions, and a progressive pupillary constriction leading to high rates of complications. The syndrome has been reported following the treatment of benign prostatic hyperplasia with α-1(a) adrenergic receptor inhibitors, especially tamsulosin. The present paper describes the syndrome and discusses its pharmacological background. Several techniques to prevent and to deal with the syndrome are presented.

Iris morphologic changes related to alpha(1)-adrenergic receptor antagonists implications for intraoperative floppy iris syndrome

PURPOSE

To identify iris structural alterations associated with intraoperative floppy iris syndrome (IFIS) in patients using systemic alpha(1)-adrenergic receptor antagonists (alpha-1ARA).

DESIGN

Cross-sectional study.

PARTICIPANTS AND CONTROLS

Twenty-nine patients with current or past treatment with any systemic alpha-1ARA and 22 untreated controls.

METHODS

Consecutive eligible patients underwent slit-lamp-adapted optical coherence tomography in a masked fashion under standardized lighting conditions.

MAIN OUTCOME MEASURES

Iris thickness at the dilator muscle region (DMR; measured at half of the distance between the scleral spur and the pupillary margin) and at the sphincter muscle region (SMR; 0.75 mm from the pupillary margin), the ratio between the DMR/SMR (to compensate for possible intersubject variability), and pupillary diameter.

RESULTS

Most treated patients were on tamsulosin (27/29). Mean age was similar in study and control groups (70.6+/-7.6 vs 67.1+/-9.1 years; P = 0.061). Photopic pupil diameter was reduced in the study group (2.06+/-0.5 vs 2.5+/-0.6 mm; P = 0.001). The SMR was similar between groups (P = 0.53). Significantly lower values were found in treated subjects for the DMR and the DMR/SMR ratio (P<0.001). These differences remained significant after adjusting for pupil diameter (P<0.001). Multiple regression analysis showed that a longer duration of alpha-1ARA treatment correlated to a reduced DMR/SMR ratio (P = 0.001; r = 0.47). Age and eye color were not significant in this model.

CONCLUSIONS

Patients using systemic alpha-1ARA have significantly lower values of DMR thickness and DMR/SMR ratio and smaller pupil diameter when compared with age-matched controls. These differences seem to be related to the duration of drug exposure and provide evidence of structural alterations to the iris dilator muscle from this class of agents in IFIS.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

Intraoperative floppy iris syndrome associated with alpha1-adrenergic receptor antagonists

OBJECTIVE

To describe intraoperative floppy iris syndrome (IFIS) in association with alpha(1)-adrenergic receptor (alpha(1)AR) antagonists by conducting a thorough literature review.

DATA SOURCES

Literature retrieval was accomplished by searching MEDLINE (2000-December 2007) using the terms intraoperative floppy iris syndrome (IFIS), adrenergic alpha-antagonist(s), tamsulosin, doxazosin, terazosin, and/or alfuzosin. In addition, reference lists from identified publications were reviewed to identify additional reports and studies of interest.

STUDY SELECTION AND DATA EXTRACTION

All articles in English identified from data sources were reviewed for relevance and uniqueness prior to inclusion.

DATA SYNTHESIS

IFIS was first described in 2005 as a clinical triad observed during cataract surgery that includes fluttering and billowing of the iris stroma, propensity for iris prolapse, and constriction of the pupil. IFIS increases the risk of complications during cataract surgery. Numerous reports have linked IFIS to use of alpha(1)AR antagonists, most notably tamsulosin, which is prescribed for benign prostatic hyperplasia. Tamsulosin blocks prostatic alpha(1A)ARs but may also selectively block alpha(1A)ARs in the iris dilator muscle, preventing mydriasis during cataract surgery. Other alpha(1)AR antagonists, including terazosin, doxazosin, and alfuzosin, have also been linked to IFIS; however, their relationship to the syndrome is not as definitive. When ophthalmologists are aware of a patient's previous alpha(1)AR antagonist exposure, specific steps can be taken to reduce the risk of surgical complications. Corrective measures used during surgery have included iris expansion hooks, intracameral phenylephrine, and preoperative atropine.

CONCLUSIONS

IFIS is a clinical syndrome observed during cataract surgery reported in patients taking systemic alpha(1)AR antagonists. It has been most strongly linked to use of tamsulosin. Medication washout periods of up to 2 weeks and specific surgical procedures have been attempted to reduce risk of complications from alpha(1)AR antagonists in the setting of cataract surgery. Patients should be educated regarding potential risks of this drug class so that they can discuss them with their healthcare providers, specifically ophthalmologists, prior to cataract surgery.