title: Impact of botulinum toxin-A on corneal curvature assessed with Scheimpflug and Placido systems.
abstract: To evaluate the effect of eyelid spasm treatment with botulinum toxin-A (BTX-A) on corneal curvature assessed with Scheimpflug (Pentacam) and Placido (Atlas) systems.
  
  
  
  Federal University of São Paulo, São Paulo, Brazil.
  
  
  
  Prospective interventional case series.
  
  
  
  Patients with hemifacial spasm were evaluated. Steep keratometry (K) and corneal astigmatism (magnitudes and treatment-induced astigmatism) obtained with the Placido and Scheimpflug systems were evaluated before BTX-A application and after 15 days and 2, 3, and 4 months.
  
  
  
  The study evaluated 48 eyes (24 affected and 24 normal contralateral eyes) of 24 patients. The mean steep K and astigmatism values obtained with the Placido system on the affected side before treatment were 46.91 diopters (D) ± 3.57 (SD) and 2.63 ± 2.46 D, respectively. A significant decrease in steep K (45.14 ± 1.20 D) and astigmatism (1.01 ± 0.58 D) was observed 2 months (P = .003 and P = .0004, respectively) and 3 months (45.64 ± 1.77 D and 1.36 ± 1.31 D, respectively) (P = .03 and P = .01, respectively) after treatment. The Scheimpflug system did not show significant changes in steep K measurements during the 4-month period. The mean astigmatism in the affected eye before treatment was 1.27 ± 0.88 D. A significant reduction was observed at 15 days (1.16 ± 1.16 D) and at 4 months (0.91 ± 0.59 D) (P = .02 and P = .03, respectively).
  
  
  
  The Placido system was more sensitive in detecting a temporary reduction in corneal curvature after eyelid-spasm treatment.
  
  
  
  None of the authors has a financial or proprietary interest in any material or method mentioned.
authors.affiliation: From the Department of Ophthalmology and Visual Sciences (T. Osaki, M.H. Osaki, T.H. Osaki, Hirai, Campos), Paulista School of Medicine, Federal University of Sao Paulo, São Paulo, Brazil; the Department of Ophthalmology (Nallasamy), Duke University Eye Center, Durham, North Carolina, USA.
authors.forename: Teissy
authors.initials: T
authors.lastname: Osaki
authors.affiliation: From the Department of Ophthalmology and Visual Sciences (T. Osaki, M.H. Osaki, T.H. Osaki, Hirai, Campos), Paulista School of Medicine, Federal University of Sao Paulo, São Paulo, Brazil; the Department of Ophthalmology (Nallasamy), Duke University Eye Center, Durham, North Carolina, USA.
authors.forename: Midori H
authors.initials: MH
authors.lastname: Osaki
authors.affiliation: From the Department of Ophthalmology and Visual Sciences (T. Osaki, M.H. Osaki, T.H. Osaki, Hirai, Campos), Paulista School of Medicine, Federal University of Sao Paulo, São Paulo, Brazil; the Department of Ophthalmology (Nallasamy), Duke University Eye Center, Durham, North Carolina, USA. Electronic address: tammyosaki@me.com.
authors.forename: Tammy H
authors.initials: TH
authors.lastname: Osaki
authors.affiliation: From the Department of Ophthalmology and Visual Sciences (T. Osaki, M.H. Osaki, T.H. Osaki, Hirai, Campos), Paulista School of Medicine, Federal University of Sao Paulo, São Paulo, Brazil; the Department of Ophthalmology (Nallasamy), Duke University Eye Center, Durham, North Carolina, USA.
authors.forename: Flavio E
authors.initials: FE
authors.lastname: Hirai
authors.affiliation: From the Department of Ophthalmology and Visual Sciences (T. Osaki, M.H. Osaki, T.H. Osaki, Hirai, Campos), Paulista School of Medicine, Federal University of Sao Paulo, São Paulo, Brazil; the Department of Ophthalmology (Nallasamy), Duke University Eye Center, Durham, North Carolina, USA.
authors.forename: Nambi
authors.initials: N
authors.lastname: Nallasamy
authors.affiliation: From the Department of Ophthalmology and Visual Sciences (T. Osaki, M.H. Osaki, T.H. Osaki, Hirai, Campos), Paulista School of Medicine, Federal University of Sao Paulo, São Paulo, Brazil; the Department of Ophthalmology (Nallasamy), Duke University Eye Center, Durham, North Carolina, USA.
authors.forename: Mauro
authors.initials: M
authors.lastname: Campos
mesh_terms: D001251:Astigmatism / Q000188:drug therapy; D001905:Botulinum Toxins; D019274:Botulinum Toxins, Type A / Q000494:pharmacology*; D003315:Cornea / Q000000981:diagnostic imaging* / Q000187:drug effects; D019781:Corneal Topography; D005141:Eyelid Diseases / Q000188:drug therapy*; D006801:Humans; D011446:Prospective Studies; D013035:Spasm / Q000188:drug therapy*
chemical_list: D001905:Botulinum Toxins; D019274:Botulinum Toxins, Type A