title: Randomized clinical trial of two anesthetic techniques for intravitreal injections: 4% liquid lidocaine on cotton swabs versus 3.5% lidocaine gel.
abstract: OBJECTIVE
  To compare same-day and next-day pain control and safety of two anesthetic techniques utilizing 4% liquid lidocaine applied with sterile cotton swabs versus 3.5% lidocaine gel for intravitreal injections. Main outcome measures were: discomfort during anesthetic preparation and needle penetration, 1 and 24 h after injection.
  
  
  METHODS
  Patients were randomized to alternate anesthetic method at two consecutive injections in one eye or in different eyes on the same day if requiring bilateral injections. Overall satisfaction, corneal staining, and subconjunctival hemorrhage (SCH) were compared.
  
  
  RESULTS
  Fifty patients were enrolled. Both methods resulted in similar mild discomfort during anesthetic preparation, 1 and 24 h later. The gel resulted in slightly higher discomfort during needle penetration (p = 0.026). Patients were satisfied with both techniques (p = 0.91), however, 52% patients preferred gel, 33% were indifferent, and 15% preferred cotton swabs (p = 0.002). There were significantly less corneal staining (p = 0.001) and SCH (p = 0.004) after the gel.
  
  
  CONCLUSIONS
  Both techniques are equally effective and yield mild discomfort scores during the procedure and the next day. The gel method results in significantly less ocular surface irritation.
authors.affiliation: University of Miami Miller School of Medicine, Bascom Palmer Eye Institute, USA. ngregori@med.miami.edu
authors.forename: Ninel Z
authors.initials: NZ
authors.lastname: Gregori
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Weiss
authors.forename: Raquel
authors.initials: R
authors.lastname: Goldhardt
authors.forename: Joyce C
authors.initials: JC
authors.lastname: Schiffman
authors.forename: Edgardo
authors.initials: E
authors.lastname: Vega
authors.forename: Cherrie-Ann
authors.initials: CA
authors.lastname: Mattis
authors.forename: Wei
authors.initials: W
authors.lastname: Shi
authors.forename: Linda
authors.initials: L
authors.lastname: Kelley
authors.forename: Vilma
authors.initials: V
authors.lastname: Hernandez
authors.forename: William J
authors.initials: WJ
authors.lastname: Feuer
mesh_terms: D000287:Administration, Topical; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000779:Anesthetics, Local / Q000008:administration & dosage / Q000627:therapeutic use*; D005260:Female; D005782:Gels; D006801:Humans; D058449:Intravitreal Injections / Q000009:adverse effects*; D008012:Lidocaine / Q000008:administration & dosage / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D010146:Pain / Q000188:drug therapy* / Q000209:etiology / Q000503:physiopathology; D010147:Pain Measurement; D011446:Prospective Studies
chemical_list: D000779:Anesthetics, Local; D005782:Gels; D008012:Lidocaine