Intraoperative Floppy Iris Syndrome in Women

Background and Rationale Intraoperative floppy iris syndrome (IFIS) represents a well-recognized surgical challenge during phacoemulsification cataract surgery, historically attributed to alpha-1 adrenergic receptor antagonist (α1-ARA) use, predominantly in men receiving treatment for benign prostatic hyperplasia. Emerging evidence suggests that IFIS in women follows a distinct epidemiological and clinical pattern: lower overall incidence but disproportionately higher severity and complication rates compared to male patients. The pharmacological and non-pharmacological determinants of IFIS in women remain incompletely characterized. This study was designed to prospectively determine the prevalence of IFIS in a female cataract population and identify its independent clinical risk factors, with emphasis on factors operating independently of α1-ARA exposure.

Data Collection Framework

Preoperative data collection is structured around three domains:

Domain 1 - Systemic history: Standardized face-to-face interview documenting comorbidities (diabetes mellitus, hypertension, thyroid dysfunction, rheumatological disease), current medications with duration of use, urinary incontinence status and its treatment, and complete surgical history (cardiovascular, abdominal, gynecologic - specifically myomectomy, hysterectomy, and bilateral salpingo-oophorectomy).

Domain 2 - Ocular parameters: Best-corrected visual acuity, slit-lamp biomicroscopy, intraocular pressure by non-contact tonometry, ocular biometry (axial length, anterior chamber depth), iris morphology (color, pseudoexfoliation, iridodonesis), and pupil diameter under scotopic, mesopic, and photopic conditions via integrated pupillography software.

Domain 3 - Pharmacological mydriasis response: Rather than a fixed time-based protocol, adequacy of dilation is confirmed by functional assessment - absence of the direct pupillary light reflex upon penlight examination by a single designated investigator. Dilated pupil diameter is recorded upon confirmed dilation. This approach was selected to capture inter-individual variability in mydriatic response, particularly relevant in patients with potential iris dilator dysfunction.

Outcome Ascertainment The primary outcome - IFIS diagnosis and grading - is determined through dual independent review. The operating surgeon provides the initial intraoperative assessment; a second senior ophthalmologist, blinded to clinical data, independently reviews the surgical video recording. IFIS classification requires consensus between both reviewers; discordant cases are not classified as IFIS. This two-reviewer consensus model minimizes ascertainment bias and ensures diagnostic consistency across the study period.

IFIS severity is graded on a four-point scale (Chang and Campbell, 2005): Grade 0 (stable iris); Grade 1 (iris billowing, no prolapse or significant miosis); Grade 2 (billowing with prolapse or ≥2 mm pupil reduction); Grade 3 (billowing with both prolapse and ≥2 mm pupil reduction).

Surgical Standardization To minimize surgeon-related confounding, all procedures are performed by three designated senior surgeons using an identical phacoemulsification platform, standardized incision architecture (2.2 mm temporal clear corneal), and uniform fluidic parameters. Intracameral epinephrine (1:10,000) is administered routinely in all cases following side-port construction. Intraoperative adjuncts - capsular tension rings, iris hooks, pupil expansion devices, and corneal sutures - are recorded as secondary outcome variables reflecting surgical complexity attributable to IFIS.

Quality Assurance Data are entered prospectively into a dedicated case record form at each patient encounter. Questionnaire responses are verified against available medical records where possible. Surgical video recordings are archived for all cases to enable post-hoc independent review and audit. IFIS grading discordances between the two reviewers are documented and adjudicated by a third senior ophthalmologist.

Inclusion criteria

• Female sex
• Age 50 years or older
• Scheduled for elective phacoemulsification cataract surgery at the study center
• Ability to provide reliable responses to the preoperative assessment questionnaire
• Written informed consent obtained

Exclusion criteria

• Cataract of non-senile etiology (traumatic, uveitic, or drug-induced)
• Iris structural or functional abnormalities including coloboma, iris neovascularization, synechiae, and iridoschisis
• History of previous intraocular surgery
• Prior iris-related laser procedures including laser iridoplasty or peripheral iridotomy
• History of scleral buckle surgery
• Inability to complete the preoperative questionnaire reliably
• IFIS diagnosis made by an assessor outside the designated review panel
• Visual acuity of light perception, light projection, or hand motion only at baseline