title: Alterations in iris structure and pupil size related to alpha-1 adrenergic receptor antagonists use: implications for floppy iris syndrome.
abstract: OBJECTIVE
  To evaluate structural alterations of iris and pupil diameters (PDs) in patients using systemic α-1-adrenergic receptor antagonists (α-1ARAs), which are associated with intraoperative floppy iris syndrome (IFIS).
  
  
  METHODS
  Eighty-eight eyes of 49 male were evaluated prospectively. Patients were assigned to 2 different groups. Study group included 23 patients taking any systemic α-1ARAs treatment, and control group included 26 patients not taking any systemic α-1ARAs treatment. All patients underwent anterior segment optical coherence tomography to evaluate iris thickness at the dilator muscle region (DMR) and at the sphincter muscle region (SMR). The PD was measured using a computerized infrared pupillometer under scotopic and photopic illumination.
  
  
  RESULTS
  The study group included 46 eyes of 23 patients and the control group included 42 eyes of 26 patients. Most treated patients were on tamsulosin (16/23). Mean age was similar in the study and control groups (61.9±7.1 vs. 60.3±8, 2 years, nonsignificant). DMR (506.5±89.4 vs. 503.6±83.5 μm), SMR (507.8±78.1 vs. 522.1±96.4 μm) and the DMR/SMR ratio (1.0±0.15 vs. 0.99±0.23 μm) was similar in the study and control groups and these differences were nonsignificant. Scotopic PDs were also similar in both groups (3.99±1.11 vs. 3.74±1.35, nonsignificant). A significantly reduced photopic PD (2.89±0.55 vs. 3.62±0.64, P<0.001) and an increased scotopic/photopic PD (1.42±0.44 vs. 1.02±0.30, P<0.001) were found in the study group.
  
  
  CONCLUSIONS
  Evaluating PD alterations might be more useful than evaluating iris structural alterations in predicting IFIS. There is still a need for a reliable method that will determine the possibility of IFIS.
authors.affiliation: Department of Ophthalmology, School of Medicine, Canakkale Onsekiz Mart University, Canakkale, Turkey. ha_tufan@hotmail.com
authors.forename: Hasan Ali
authors.initials: HA
authors.lastname: Tufan
authors.forename: Baran
authors.initials: B
authors.lastname: Gencer
authors.forename: Selcuk
authors.initials: S
authors.lastname: Kara
authors.forename: Arzu Taskiran
authors.initials: AT
authors.lastname: Comez
authors.forename: Hasan Anil
authors.initials: HA
authors.lastname: Kurt
authors.forename: Cabir
authors.initials: C
authors.lastname: Alan
mesh_terms: D058668:Adrenergic alpha-1 Receptor Antagonists / Q000009:adverse effects / Q000494:pharmacology*; D000368:Aged; D003623:Dark Adaptation; D003936:Diagnosis, Computer-Assisted; D003941:Diagnostic Techniques, Ophthalmological; D006801:Humans; D007431:Intraoperative Complications / Q000139:chemically induced / Q000473:pathology; D007498:Iris / Q000187:drug effects* / Q000378:metabolism; D007499:Iris Diseases / Q000139:chemically induced* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D010775:Photic Stimulation; D011446:Prospective Studies; D011680:Pupil / Q000187:drug effects*; D013449:Sulfonamides / Q000009:adverse effects / Q000494:pharmacology; D000077409:Tamsulosin; D041623:Tomography, Optical Coherence
chemical_list: D058668:Adrenergic alpha-1 Receptor Antagonists; D013449:Sulfonamides; D000077409:Tamsulosin