Intraoperative Floppy Iris Syndrome
Definition
Intraoperative floppy iris syndrome abbreviated as IFIS is a risk factor for complications during a cataract surgery, which is a procedure that is used to treat the clouding of the eye’s lens or the cataract. IFIS was observed in those individuals who took oral drug tamsulosin for some other reasons. Tamsulosin is a type of drug that is included to a group referred to as alpha 1 antagonists.
This drug is usually used to treat lower urinary tract symptoms of non-cancerous hypertrophy. An individual who has taken oral tamsulosin before a cataract surgery could be affected by a complication during surgery, which adds up to IRIS. This condition is distinguished by poor dilation of the eye’s pupil, flaccid iris, and possibility of iris prolapse. Other than tamsulosin, there are other alpha antagonists that are also associated with IRIS.
Intraoperative Floppy Iris Syndrome can be classified based on its severity:
- Mild Form – Pupil of the eye is well-dilated before surgery and some iris billowing during the surgical procedure
- Moderate Form – Pupil of the eye is mildly dilated before surgery and mild possibility of iris prolapse through ocular incisions
- Severe Form – Small pupils that prevent dilation and marked iris prolapse in the course of surgery
Symptoms of Intraoperative Floppy Iris Syndrome
Tamsulosin drug can cause a loss of tone of the iris leading to the following characteristics during cataract surgery:
- Proneness of the iris to prolapse through surgical cuts
- Poor dilation of the pupil which is needed during surgery
- Tendency of the iris to flop
Intraoperative Floppy Iris Syndrome could cause problems during cataract surgery such as damage to the iris, vitreous layer, and the lens.
Causes
Intraoperative Floppy Iris Syndrome may be caused by the following:
Benign prostatic enlargement – This typically affects elderly men resulting in urination problems. The urethra, neck, prostate, and bladder contain receptors that are called alpha 1 receptors. In the case of benign prostatic enlargement, the blockage of these receptors with alpha 1 antagonist could help in relieving the symptoms. The iris of the eye also have the exact receptors; therefore as a side effect of the alpha 1 antagonist drugs, the receptors are also blocked when these medications are taken orally. A person who takes an alpha 1 antagonist and goes through cataract surgery might experience the ill repercussions of the drug on the eye as a consequence and eventually results to IRIS.
Alpha 1 receptor antagonists such as:
- Tamsulosin
- Indoramine
- Doxazosin
- Prazosin
- Terazosin
- Alfuzosin
There are also other drugs that contain additional alpha blocking properties which are also linked with IFIS. These involve:
- Antidepressants
- Antipsychotics such as zuclopentixole and chlorpromazine
- Beta blockers like labetalol
Other drugs that are also associated with IFIS are:
- Dietary supplements such as saw palmetto
- 5-alpha reductase inhibitors like dutasteride and finasteride
Treatment
Intraoperative Floppy Iris Syndrome could be treated and prevented by maintaining the dilation of the eye’s pupil and restraining an iris prolapse during cataract surgery. This can be done by pharmacologic and mechanical treatments along with proper phacoemulsification fluidic parameters in the course of surgery.
The use of iris hooks or expansion rings is considered the most dependable method in preserving an adequate pupil throughout the cataract surgery in acute cases of the condition. Other possible options that could help in treating IRIS may include:
Pharmacologic Agents:
- Preoperative atropine – Given at different intervals prior to surgery
- Intraoperative epinephrine or phenylephrine – Injected under the iris
Make changes to improve phacoemulsification to include:
- Lower vacuum (<22mL/min)
- Lower aspiration flow (<200 mm Hg)
Viscoelastic agents – These are preferably used with vacuum settings and phacoaspiration. They can be effective, but frequently requires repeated injections.
It is not overwhelming that studies simply come up with a conclusion that expanding the pupil or retracting the iris by some point is the only method that can be trusted in managing severe IFIS.
References:
- Floppy Iris Syndrome causes, symptoms, prevention at http://www.medindia.net/patients/patientinfo/floppy-iris-syndrome.htm
- Intraoperative Floppy Iris Syndrome: Pathophysiology, Prevention, and Treatment at http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2814568/
- http://www.medscape.com/viewarticle/748742_5
- Oshika T, Ohashi Y, Inamura M, Ohki K, Okamoto S, Koyama T, et al (2007). Incidence of intraoperative floppy iris syndrome in patients on either systemic or topical alpha (1)-adrenoceptor antagonist. Am J Ophthalmol. 143:150–1.
- Chadha V, Borooah S, Tey A, Styles C Singh J (2007). Floppy iris behaviour during cataract surgery: Associations and variations. Br J Ophthalmol. 91:40–2.
- Settas G, Fitt AW (2006). Intraoperative floppy iris syndrome in a patient taking alfuzosin for benign prostatic hypertrophy. Eye. 20:1431–2.
