title: Surgically Induced Corneal Astigmatism Following Intravitreal Ranibizumab Injection.
abstract: OBJECTIVE
  To evaluate surgically induced astigmatism (SIA) after an intravitreal ranibizumab (IVR) injection.
  
  
  METHODS
  Fifty eight eyes of 58 patients who underwent IVR injection due to age-related macular degeneration (wet form) or macular edema were included in this study. Patients' pre- and postoperative detailed ophthalmologic examinations were done and topographic keratometric values (K1, K2) were noted. Pre- and postoperative measurements were compared.
  
  
  RESULTS
  The mean preoperative astigmatism of 0.87 Diopters (D) was found to be 0.95 D, 0.75 D, 0.82 D and 0.78 D on the 1st day, 3rd day, 1st week and 1st month, respectively. After injection, absolute change in astigmatism was found to be 0.08 D, 0.12 D, 0.05 D and 0.09 D on the 1st day, 3rd day, 1st week and 1st month, respectively. The absolute change in astigmatism seemed to be insignificant in terms of refractive analysis, however; when we performed a vectorial analysis, which takes into account changes in the axis of astigmatism, the mean value of induced astigmatism were found to be 0.33±0.22 D, 0.32±0.29 D, 0.41±0.37 D, 0.46±0.32 D on the 1st day, 3rd day, 1st week and on 1st month, respectively.
  
  
  CONCLUSIONS
  Intravitreal injection is a minimally invasive ophthalmologic procedure, however; it may still cause statistically significant induced astigmatism when evaluated from a vectorial point of view.
authors.affiliation: Department of Ophthalmology, Faculty of Medicine, Adnan Menderes University, Aydın, Turkey.
authors.forename: Tolga
authors.initials: T
authors.lastname: Kocatürk
authors.affiliation: Department of Ophthalmology, Faculty of Medicine, Adnan Menderes University, Aydın, Turkey.
authors.forename: Erol
authors.initials: E
authors.lastname: Erkan
authors.affiliation: Department of Ophthalmology, Faculty of Medicine, Ege University, Izmir, Turkey.
authors.forename: Sait
authors.initials: S
authors.lastname: Eğrilmez
authors.affiliation: Department of Ophthalmology, Faculty of Medicine, Adnan Menderes University, Aydın, Turkey.
authors.forename: Harun
authors.initials: H
authors.lastname: Çakmak
authors.affiliation: Department of Ophthalmology, Faculty of Medicine, Adnan Menderes University, Aydın, Turkey.
authors.forename: Sema O
authors.initials: SO
authors.lastname: Dündar
authors.affiliation: Department of Ophthalmology, Faculty of Medicine, Adnan Menderes University, Aydın, Turkey.
authors.forename: Volkan
authors.initials: V
authors.lastname: Dayanir
keywords: Intraocular pressure; intravitreal injection; ranibizumab; surgically induced astigmatism; vectorial analysis.