gms | German Medical Science

The intraoperative floppy iris syndrome (IFIS) is a frequent syndrome which currently occurs during cataract surgery (1-2%). It has been first published by David Chang in 2005 and has been associated with a 4-fold increased risk of intraoperative surgical complications as severe iris traumatism, posterior capsule rupture or vitreous loss. 3 severity grades have been described: grade 1 (mild IFIS) with an iris billowing and no significant myosis or iris prolapse, grade 2 (moderate IFIS) with an iris billowing, a significant myosis (<2mm) and no iris prolapse, and grade 3 (severe IFIS) associating an iris billowing, a significant myosis (>2mm) and an iris prolapse. Severe IFIS characterized by this triad of clinical signs is particularly associated with an increased risk of severe intraoperative complicationsmainly when it is not anticipated by the surgeon.

The chronic use (or a history of chronic use) of alpha-blockers to treat benign prostatic hyperplasia, and particularly the use of tamsulosinis the main risk factor associated with a higher incidence and severity of IFIS .Tamsulosin is a selective antagonist of α1-a subtype adrenergic receptors. The selective blockade of α1-a prostatic dilator muscle receptors is also associated with a blockade of α1-a iris dilator muscle receptors which is responsible for a higher incidence of IFIS in this population of patient (57-82%). Moreover the chronic use of alpha-blockers results in an atrophy of iris dilator muscles explaining why to stop the instillation, even many years before cataract surgery, does not decrease the risk. High blood pressure and some other medications have also been described to be associated with the incidence of IFIS.

As the incidence of cataract and benign prostatic hyperplasia are both increasing with increasing age, urologists should be asked to prescribe a non selective alpha-blockers for phakic patients who require a medical treatment for benign prostatic hyperplasia. During surgery, when pupil diameter is too small, iris retractors should be used to perform cataract surgery safely. When pupil diameter is large enough to perform the procedure, intracameral epinephrine or atropine could be useful to maintain pupil dilation during the procedure. Finally low infusion and aspiration levels, and smooth intracameral maneuvers are required to preserve the tonicity of the iris during surgery.