What eye test is used to diagnose Intraoperative Floppy Iris Syndrome (IOFIS) with anticipated iris prolapse in an adult patient undergoing cataract surgery?

Diagnosis of Intraoperative Floppy Iris Syndrome (IFIS) with Anticipated Iris Prolapse

IFIS with anticipated iris prolapse is diagnosed primarily through preoperative clinical screening and history-taking, not through a specific eye test, though gonioscopy and anterior segment imaging may help assess angle anatomy and iris configuration in complex cases.

Preoperative Identification Strategy

IFIS cannot be diagnosed by a single eye test because it manifests during surgery. The key is identifying high-risk patients before entering the operating room through systematic screening 1, 2.

Critical Preoperative Screening Elements

Medication History (Most Important)

• Document current or prior use of α1-adrenergic receptor antagonists, particularly tamsulosin (Flomax), as IFIS can occur even after discontinuation 2, 3
• Screen for antipsychotic medications, which are emerging risk factors 2
• Ask about 5α-reductase inhibitors used for benign prostatic hyperplasia 3

Patient Demographics and Comorbidities

• Screen both men and women—women are also susceptible to IFIS 2
• Document history of hypertension, which increases IFIS risk 3
• Note advanced age as a risk factor 3

Ocular Parameters

• Measure axial length, as longer eyes may have increased risk 3
• Assess baseline pupil size and reactivity during slit-lamp examination 4

Relevant Imaging When Indicated

While no specific test "diagnoses" IFIS preoperatively, certain imaging modalities help assess anatomical risk factors:

Gonioscopy

• Evaluates anterior chamber angle configuration and depth 4
• Identifies narrow angles that may complicate surgical management if IFIS occurs 4

Anterior Segment Optical Coherence Tomography (AS-OCT)

• Assesses anterior chamber depth and iris configuration 4
• Useful for complex anterior pathology evaluation 4

Ultrasound Biomicroscopy (UBM)

• Provides superior characterization of posterior iris and ciliary body compared to AS-OCT 4
• More operator-dependent but better for identifying plateau iris configuration 4
• Can visualize iris-lens relationships that may predict surgical difficulty 4

Clinical Recognition During Surgery

The actual diagnosis occurs intraoperatively when the classic triad appears 1, 5, 6:

• Progressive pupillary constriction despite preoperative dilation
• Billowing and flaccidity of the iris stroma
• Iris prolapse toward phacoemulsification and side-port incisions

Common Pitfalls to Avoid

Screening Only Men

• Women can develop IFIS, particularly those on antipsychotics or with hypertension 2
• Failure to screen women leads to unexpected intraoperative complications

Assuming Medication Discontinuation Eliminates Risk

• IFIS can occur even after stopping α1-antagonists, as the iris changes may be permanent 2, 3
• Always document prior use, not just current medications

Inadequate Preoperative Communication

• Urologists should inform patients starting α1-antagonists about potential cataract surgery complications 6
• Ophthalmologists must specifically ask about these medications, as patients may not volunteer the information 5

Practical Algorithm for Preoperative Assessment

1. Universal screening questionnaire for all cataract surgery patients asking about α1-antagonists, antipsychotics, and hypertension 2, 3

2. If high-risk factors identified: Document in surgical plan and prepare intraoperative interventions (iris hooks, pupil expansion devices, intracameral epinephrine, higher viscosity viscoelastics) 1, 2, 5

3. Consider advanced imaging (AS-OCT or UBM) only if additional anterior segment pathology suspected (narrow angles, plateau iris, lens subluxation) that would compound IFIS management 4

4. Counsel patient about increased surgical complexity and slightly higher complication risk, but emphasize that with proper preparation, outcomes remain excellent 5