Intraoperative Floppy Iris Syndrome (IFIS): A Summary

Amr Mousa

Introduction

Intraoperative Floppy Iris Syndrome (IFIS) is a condition first described by Chang and Campbell in 2005 (1). It is characterized by abnormal iris behaviour during cataract surgery, particularly in patients taking systemic alpha-1 adrenergic antagonists like tamsulosin. Recognizing and managing IFIS is crucial for preventing intraoperative complications and ensuring favourable surgical outcomes.

Epidemiology

The prevalence of IFIS varies but is strongly associated with the use of alpha-1 adrenergic receptor antagonists prescribed for conditions like benign prostatic hyperplasia (BPH). Among these, tamsulosin, a selective alpha-1A antagonist, has the strongest link to IFIS (1). Other drugs, including doxazosin and terazosin, have also been implicated, albeit less frequently (2). IFIS has been reported in both males and females, despite the higher prevalence of tamsulosin use in males.

Pathophysiology

The mechanism of IFIS is thought to involve the blockade of alpha-1 adrenergic receptors in the iris dilator muscle, leading to poor mydriasis and increased iris flaccidity. This results in:

  1. Progressive Intraoperative Miosis: Constriction of the pupil during surgery despite preoperative dilation (1).
  2. Floppy Iris: Billowing of the iris in response to intraocular fluid currents (1).
  3. Iris Prolapse: Tendency of the iris to prolapse towards surgical incisions (2).

Clinical Features

Patients with IFIS may present with the following intraoperative challenges:

  • Poor pupillary dilation, often resistant to standard mydriatic agents (1).
  • Billowing and flaccid iris during irrigation and aspiration phases of surgery (2).
  • Recurrent iris prolapse through corneal or side port incisions (3).

Diagnosis

A diagnosis of IFIS is made based on the intraoperative findings described above. A thorough preoperative history is essential, particularly regarding the use of alpha-1 adrenergic antagonists (1). Stopping tamsulosin preoperatively does not always prevent IFIS, as its effects on the iris may persist for months (4).

Management Strategies

Managing IFIS requires a combination of preoperative, intraoperative, and postoperative strategies:

Preoperative Measures

  1. Medication History: Identify high-risk patients by reviewing systemic medications (1).
  2. Pupil Dilation Protocols: Use additional or stronger mydriatics and cycloplegics (5).

Intraoperative Measures

  1. Use of Iris Hooks or Rings: Mechanical devices help stabilize the iris and maintain dilation (3).
  2. Viscoelastic Agents: High-viscosity ophthalmic viscoelastic devices (OVDs) such as Healon-GV can help dilate the pupil and prevent iris billowing (4). However, care should be taken as overfilling the AC can encourage the iris to prolapse
  3. Low-Flow Phacoemulsification: Adjust irrigation and aspiration parameters to minimize fluid turbulence (3).
  4. Long incisions: Longer wound architecture reduces the risk of iris prolapse (5).

Postoperative Measures

Monitor for complications such as:

  • Inflammation and prolonged recovery (2).
  • Cystoid macular edema (4).
  • Secondary glaucoma (5).

Prognosis

With careful preoperative planning and intraoperative management, most cases of IFIS can be successfully managed without significant impact on visual outcomes. However, unrecognized or poorly managed IFIS may lead to complications such as posterior capsular rupture or prolonged surgery time (1).

References

  1. Chang DF, Campbell JR. Intraoperative floppy iris syndrome associated with tamsulosin. Journal of Cataract & Refractive Surgery. 2005;31(4):664-673.
  2. Neff KD, Sandoval HP, Fernandez de Castro LE, et al. Factors associated with intraoperative floppy iris syndrome. Ophthalmology. 2009;116(4):658-663.
  3. Blouin MC, Blouin J, Perreault S, et al. Tamsulosin and the risk of intraoperative floppy-iris syndrome: A case-control study. American Journal of Ophthalmology. 2007;144(4):712-714.
  4. Braga-Mele R, Chang D, et al. Clinical management of intraoperative floppy-iris syndrome: Survey results of the ASCRS Cataract Clinical Committee. Journal of Cataract & Refractive Surgery. 2008;34(7):1201-1209.
  5. Oshika T, Inamura M, et al. Incidence of intraoperative floppy-iris syndrome in patients on systemic alpha1-adrenoceptor antagonist. Eye. 2007;21(6):865-867.

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