title: Intracameral acetylcholine effectively contracts pupils after dilatation with intracameral mydriatics.
abstract: OBJECTIVE
  To determine whether intracameral acetylcholine can contract pupils dilated with intracameral mydriatics in phacoemulsification cataract surgery.
  
  
  METHODS
  A total of 60 patients were included in this prospective randomized masked study performed at Örnsköldsviks Hospital Eye Clinic. The patients were randomized and were given either topical placebo and an intracameral mydriatic solution (ICM) (cyclopentolate 0.1%, phenylephrine 1.5% and xylocaine 1%) (n = 30) or topical mydriatics (TM) (cyclopentolate 0.85% and phenylephrine 1.5%) and xylocaine 1% intracamerally (n = 30) at the start of surgery. After intraocular lens (IOL) implantation, 0.15 ml 1% acetylcholine was given intracamerally in all cases. The pupil size was registered preoperatively, 45 seconds after intracameral injection, after ophthalmic viscosurgical device (OVD) evacuation, 30 seconds after acetylcholine injection, 2 min after acetylcholine injection and the day after surgery.
  
  
  RESULTS
  The pupil contraction and pupil size after acetylcholine injection showed no significant differences at 30 seconds (contraction 1.0 ± 0.4 in ICM group versus 0.9 ± 0.4 in TM group; p = 0.75; size 4.8 ± 1.1 in the ICM group versus 5.2 ± 1.1 in the TM group; p = 0.24) or at 2 min (contraction 1.5 ± 0.6 in the ICM group versus 1.4 ± 0.6 in the TM group; p = 0.63; size 4.3 ± 0.9 in the ICM group versus 4.7 ± 1.0 in the TM group; p = 0.13). No difference in baseline pupil size after ophthalmic viscosurgical device (OVD) evacuation was seen between the two groups (5.8 ± 0.9 in the ICM group versus 6.1 ± 1.2 in the TM group; p = 0.28).
  
  
  CONCLUSIONS
  We here show that intracameral acetylcholine contracts pupils as effectively after dilatation with intracameral mydriatics as after dilatation with topical mydriatics. Cataract surgeons can feel comfortable and safe when using intracameral mydriatics, even if pupil contraction with acetylcholine should be required.
authors.affiliation: Eye Clinic, Örnsköldsviks Hospital, Örnsköldsvik, Sweden. gunnie.backstrom@lvn.se
authors.forename: Gunnie
authors.initials: G
authors.lastname: Bäckström
authors.forename: Björn
authors.initials: B
authors.lastname: Lundberg
authors.forename: Anders
authors.initials: A
authors.lastname: Behndig
mesh_terms: D000109:Acetylcholine / Q000627:therapeutic use*; D000368:Aged; D000867:Anterior Chamber / Q000187:drug effects; D018679:Cholinergic Agonists / Q000627:therapeutic use*; D003519:Cyclopentolate / Q000008:administration & dosage; D004311:Double-Blind Method; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D019654:Lens Implantation, Intraocular; D008012:Lidocaine / Q000008:administration & dosage; D008297:Male; D009184:Mydriatics / Q000008:administration & dosage*; D018918:Phacoemulsification; D010656:Phenylephrine / Q000008:administration & dosage; D011446:Prospective Studies; D011680:Pupil / Q000187:drug effects*
chemical_list: D018679:Cholinergic Agonists; D009184:Mydriatics; D010656:Phenylephrine; D008012:Lidocaine; D003519:Cyclopentolate; D000109:Acetylcholine