title: Clinical study of pain sensation during phacoemulsification with and without cryoanalgesia.
abstract: OBJECTIVE
  To compare the analgesic efficacy of 2 types of anesthetic techniques-topical and topical associated with cryoanalgesia-during cataract surgery.
  
  
  METHODS
  Department of Ophthalmology, University of São Paulo, Ribeirão Preto, Brazil.
  
  
  METHODS
  Prospective randomized study.
  
  
  METHODS
  Patients with symmetrical bilateral cataract had phacoemulsification with the use of an intraocular irrigation solution at room temperature in 1 eye and a cold (4°C) solution in the contralateral eye (Group 2). The pain related to the procedure was assessed using a visual analog scale ranging from 0 to 100, with 0 representing no pain and 100 the worst pain. In addition, endothelial cell loss, the change in corneal thickness, and visual acuity were evaluated 30 days ± 2 (SD) after each surgery. The surgery duration, total irrigation volume, phacoemulsification time, and ultrasound power used were analyzed.
  
  
  RESULTS
  The study enrolled 25 patients (50 eyes). There was no statistically significant difference in the mean pain score between Group 1 (26.0 ± 3.7) and Group 2 (21.3 ± 3.6) (P = .2016, paired t test). No significant difference was found in the mean corneal endothelial cell loss (Group 1: 10.0% ± 0.4%; Group 2: 9.9% ± 0.3%; P = .7576), corneal thickness increase (Group 1: 1.5 ± 1.0 μm; Group 2: 1.4 ± 0.9 μm; P = .9340), or visual acuity gain (Group 1: 0.54 ± 0.06 logMAR; Group 2: 0.55 ± 0.09 logMAR; P = .8208).
  
  
  CONCLUSIONS
  There is no difference in the intensity of pain during phacoemulsification with the use of topical anesthesia or topical anesthesia associated with cryoanalgesia.
  
  
  BACKGROUND
  No author has a financial or proprietary interest in any material or method mentioned.
authors.affiliation: From the Department of Ophthalmology, Otorrinolaringology and Head and Neck Surgery, Medical School of Ribeirão Preto, University of São Paulo-Ribeirão Preto, São Paulo, Brazil. Electronic address: robertopintocoelho1@gmail.com.
authors.forename: Roberto Pinto
authors.initials: RP
authors.lastname: Coelho
authors.affiliation: From the Department of Ophthalmology, Otorrinolaringology and Head and Neck Surgery, Medical School of Ribeirão Preto, University of São Paulo-Ribeirão Preto, São Paulo, Brazil.
authors.forename: Ricardo Helio
authors.initials: RH
authors.lastname: Biaggi
authors.affiliation: From the Department of Ophthalmology, Otorrinolaringology and Head and Neck Surgery, Medical School of Ribeirão Preto, University of São Paulo-Ribeirão Preto, São Paulo, Brazil.
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Jorge
authors.affiliation: From the Department of Ophthalmology, Otorrinolaringology and Head and Neck Surgery, Medical School of Ribeirão Preto, University of São Paulo-Ribeirão Preto, São Paulo, Brazil.
authors.forename: Maria de Lourdes Veronese
authors.initials: Mde L
authors.lastname: Rodrigues
authors.affiliation: From the Department of Ophthalmology, Otorrinolaringology and Head and Neck Surgery, Medical School of Ribeirão Preto, University of São Paulo-Ribeirão Preto, São Paulo, Brazil.
authors.forename: André
authors.initials: A
authors.lastname: Messias
mesh_terms: D000368:Aged; D000698:Analgesia / Q000379:methods; D000772:Anesthesia, Local / Q000379:methods; D000779:Anesthetics, Local; D002386:Cataract / Q000150:complications; D055954:Corneal Endothelial Cell Loss / Q000473:pathology; D017679:Cryotherapy / Q000379:methods*; D058447:Eye Pain / Q000175:diagnosis*; D005260:Female; D006801:Humans; D019654:Lens Implantation, Intraocular; D008297:Male; D010147:Pain Measurement; D018918:Phacoemulsification / Q000379:methods*; D011446:Prospective Studies; D014792:Visual Acuity
chemical_list: D000779:Anesthetics, Local