Dr Edsel Ing

Research project: Giant Cell Arteritis: Diagnostic Prediction Models, Temporal Artery Biopsy & Epidemiology


     Giant cell arteritis (GCA) is the most common primary vasculitis in the elderly and can cause irreversible blindness, aortitis, and stroke.   Diagnostic confirmation of GCA usually entails temporal artery biopsy (TABx) – a time-consuming and invasive test, or ultrasound.  The primary treatment of GCA is with high dose glucocorticoids which have numerous potential side effects.  Glucocorticoids are initiated prior to the TABx result, due to the risk of interim blindness. By 2050 the cost of blindness from GCA in the United States is estimated at $76 billion with an additional $6 billion from glucocorticoid-induced fractures.

     This thesis examines knowledge gaps in the diagnosis and epidemiology of GCA.  Needed refinements in the diagnosis of GCA included:  i) the optimization of diagnostic prediction models (PMs) and ii) clarification of the contemporary utilization parameters of TABx.  With regards to i) previous PMs are usually based on limited sample size, do not leverage sufficient clinical predictors or include continuous variables, and not compliant with the transparent reporting guidelines for PMs (TRIPOD).  Using multicentre data of consecutive patients undergoing TABx, the largest (n=1,201) and most comprehensive logistic regression and, neural network PMs for GCA were formulated; age, platelet level, jaw claudication and vision loss eventuated as the key predictor variables. An online risk calculator was developed from the PM and may decrease both the number of TABx performed on low-risk patients, and the morbidity from unneeded glucocorticoids.   Regarding ii) although TABx has long been acknowledged as the gold standard test for GCA the current preference of TABx versus ultrasound amongst neuro-ophthalmologists and the utility rate of TABx are unknown.  The thesis survey revealed that 91% of neuro-ophthalmologists preferred TABx over ultrasound as the confirmatory test for GCA. The first systematic review for the utility rate of TABx disclosed a median positive yield of 25% and provides a benchmark for institutions performing this procedure.

     Knowledge gaps in the epidemiology of GCA important for public health planning included the incidence of GCA in Ontario, Canada, and the controversial role of herpes zoster in the development of GCA given the advent of the shingles vaccine.  Pathology audit and an assay of billing data revealed the incidence of biopsy-proven GCA in Ontario was 4.9 per 100,000 individuals 50 years of age or older.  On ecologic analysis, the inverse relationship of the incidence rates of herpes zoster versus GCA per country suggested shingles is not a major immunopathogenic trigger for GCA.

  • Research degree: PhD by prior publication/portfolio
  • Title of project: Giant Cell Arteritis: Diagnostic Prediction Models, Temporal Artery Biopsy & Epidemiology
  • Research supervisors:


Medical School and Ophthalmology Residency:  University of Toronto

Fellowships:  Mayo Clinic, Wills Eye Hospital, Allegheny General Hospital

Masters of Public Health:  Harvard School of Public Health

Masters of International Affairs and Diplomacy:  UNITAR & University of Catalonia

Global Clinical Scholars Research Training Certificate:  Harvard Medical School

Education for the Health Professions Certificate:  Johns Hopkins

Current Appointment:  Associate Professor, University of Toronto, Department of Ophthalmology & Vision Sciences

Areas of research interest

  • Giant Cell Arteritis
  • Neuro-ophthalmology
  • Epidemiology
  • Oculoplastics
  • Strabismus
  • Graves Orbitopathy
  • Public Health


  • MD, University of Toronto
  • FRCSC, Royal College of Physicians and Surgeons of Canada
  • MPH, Epidemiology, Harvard
  • MIAD, United Nations Institute for Research and Training and the University of Catalonia
  • CPH: National Board of Public Health Examiners

Funding or awards received

  • Royal College of Physicians and Surgeons Regional Continuing Professional Development Activity Grant
  • Excellence in Clinical Teaching Award, Professional Associations of Residents of Ontario


Ing EB. Neural network and logistic regression predictive calculator for giant cell arteritis. Red neuronal y calculadora predictiva de regresión logística para la arteritis de células gigantes. Arch Soc Esp Oftalmol. 2019;94(12):622.

Sivakumar GK, Liu J, Sokoluk C, Ing EB. Online calculator for hydroxychloroquine dosing [published online ahead of print, 2020 Feb 18]. Can J Ophthalmol. 2020;S0008-4182(19)31337-7. 

Ing EB, Kam JWK, Cheng JZ, et al. Incidence of nonarteritic ischemic optic neuropathy following topical clear corneal cataract surgery: survey and meta-analysis. Can J Ophthalmol. 2020;55(1):87–92. 

Ing EB, Bedi H, Hussain A, et al. Meta-analysis of randomized controlled trials in dacryocystorhinostomy with and without silicone intubation. Can J Ophthalmol. 2018;53(5):466–470. 

Ing EB, Ing R, Liu X, et al. Does herpes zoster predispose to giant cell arteritis: a geo-epidemiologic study. Clin Ophthalmol. 2018;12:113–118.

Ing E, Ing T, Ing S. The effect of a hockey visor and sports goggles on visual function. Can J Ophthalmol. 2002;37(3):161–167.

·Country-wide Mortality from the Novel Coronavirus (COVID-19) Pandemic and Notes Regarding Mask Usage by the Public Leffler C, Ing E, Mckeown CA, Grzybowski A.  April 2020  DOI: 10.13140/RG.2.2.36006.27200

Conference papers

Ing E.  Canadian Ophthalmological Society, 2019.  1)  Graves Orbitopathy https://www.youtube.com/watch?v=n2_8q1Uwx6w   2)  Temporal Artery Biopsy and the Oculoplastic Surgeon  https://www.youtube.com/watch?v=pWcm308l3wk

Ing E.  Thinking Beyond the Black and White – Oculoplastic and Orbital Imagingfor the Primary Care Doctor.  Ontario Medical Association. 40th Annual Day in Primary Eye Care.  Dec 15, 2018.

Ing E., Non-arteritic Anterior Ischemic Optic Neuropathy and Strabismus after Cataract Surgery.  58th Annual Walter Wright Symposium.   University of Toronto, Nov 30, 2018.

Ing E et al.  Neural Network Diagnostic Prediction Model for Giant Cell Arteritis:  Development and Validation.  University of Toronto.  14th Annual Faculty Research Day.  Nov 16, 2018.

Ing E., The Eye and Acoustic Schwannoma, Acoustic Neuroma Association of Canada, Toronto, UHN, Sept 29, 2018.

Ing E.  Lethal Autonomous Weapons Thesis, 2019, https://www.youtube.com/watch?v=EkuN4OKdFww