title: Growth of medical and surgical vitreoretinal subspecialization in Ontario over 12 years.
abstract: OBJECTIVE
  The past decade has seen significant paradigm shifts in the management of many retinal diseases. The goal of this study is to assess the effect these advances have had on the number of retinal specialists, and the differences in output between medical and surgical specialists at the population level.
  
  
  METHODS
  Population-based analysis of surgical and medical retina therapeutic and diagnostic procedures among all ophthalmologists in Ontario, Canada, from April 1999 to March 2012.
  
  
  METHODS
  This study included all ophthalmologists with an Ontario license and receiving remuneration from the Ontario Health Insurance Plan (OHIP). Ophthalmologists were categorized as a surgical or medical retina specialist based on the type and volume of retina-specific procedures performed each year.
  
  
  METHODS
  The IntelliHealth database operated by the Ministry of Health and Long Term Care was used to obtain anonymized physician services, which has excellent accuracy for procedure performance.
  
  
  RESULTS
  The number of retina specialists grew from 9.7% to 14.4% of the ophthalmology workforce. The proportion of late-career retina specialists (>25 years since graduation) doubled but had no influence on procedure output. Almost all retina specialists (90%) practice in the region they graduated medical school, and most (65%) practice in counties with a population greater than 400,000 people. Over the study period, the mean number of photocoagulation and fluorescein angiography performed was significantly higher among surgical retina specialists. Scleral buckling declined by 55% over the study period, whereas the number of pars plana vitrectomies grew by 49%.
  
  
  CONCLUSIONS
  The retina subspecialty is a growing area of ophthalmology and is mainly located in urban centres. There has been a dramatic shift in the types of procedures performed to treat medical and surgical diseases over the past decade. To our knowledge, this is the first study to quantify differences in diagnostic and procedure performance between the medical and surgical retina subspecialties.
authors.affiliation: Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto. Electronic address: jonathan.micieli@utoronto.ca.
authors.forename: Jonathan A
authors.initials: JA
authors.lastname: Micieli
authors.affiliation: Faculty of Medicine, University of Ottawa, Ottawa, Ont.
authors.forename: Andrew
authors.initials: A
authors.lastname: Micieli
authors.affiliation: Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto.
authors.forename: Matthew B
authors.initials: MB
authors.lastname: Schlenker
authors.affiliation: Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto.
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Kertes
mesh_terms: D016208:Databases, Factual; D003695:Delivery of Health Care / Q000706:statistics & numerical data; D005260:Female; D006302:Health Services Research; D006280:Health Workforce / Q000706:statistics & numerical data*; D006801:Humans; D058449:Intravitreal Injections / Q000706:statistics & numerical data; D008297:Male; D008511:Medicine / Q000706:statistics & numerical data*; D009864:Ontario / Q000453:epidemiology; D009885:Ophthalmology / Q000706:statistics & numerical data; D010818:Practice Patterns, Physicians' / Q000706:statistics & numerical data; D057586:Vitreoretinal Surgery / Q000706:statistics & numerical data*