Gillian McLellan, BVMS, PhD, DACVO, DECVO, DVOphthal, MRCVS, FARVO  Professor, Tim and Nancy Speaker Chair in Canine Health

Department of Surgical Sciences
Office: 2023

Gillian McLellan, BVMS, PhD, DACVO, DECVO, DVOphthal, MRCVS, FARVO  Professor, Tim and Nancy Speaker Chair in Canine Health

Titles and Education

  1. European Specialist in Veterinary Ophthalmology
  2. Diplomate ACVO, 2004
  3. Diplomate ECVO, 2003
  4. DVOphthal, Royal College of Veterinary Surgeons, 2001
  5. PhD, University of London, 2000
  6. CertVOphthal, Royal College of Veterinary Surgeons, 1993
  7. BVMS, University of Glasgow Veterinary School, 1990
  8. President, European College of Veterinary Ophthalmologists (2012-2014)



Dr McLellan’s main area of research focus is comparative glaucoma, including imaging of the retina and optic nerve, electrophysiology, aqueous humor dynamics, genetics and pathology of glaucoma in animals and humans

Dr McLellan also has a strong research interest in Alzheimer's disease, its association with glaucoma and similarities to feline cognitive dysfunction syndrome in older cats.  More general interests include comparative ophthalmic pathology; diseases of the retina and optic nerve in dogs and cats; the ocular and systemic effects of vitamin E deficiency in dogs, and drug toxicities affecting the retina in humans and animals.


Professor in Comparative Ophthalmology, Dept of Surgical Sciences, School of Veterinary Medicine and Dept of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health

Program Director:  NIH Shared Instrumentation Grant for Multimodal Imaging of the Eye

Member, McPherson Eye Research Institute Leadership Committee

Board Member, ACVO Vision for Animals Foundation

Clinical Interests

Glaucoma in all species
Feline ophthalmology
Advanced imaging of the eye and orbit

Retinal and optic nerve disease
Ocular pathology / clinical pathology


Graduate Training

Trainer: Comparative Biomedical Sciences Graduate Program

Recent Publications

  1.  Click here for a complete list of published work
  2. Minella AL, Kiland JA, Gloe S, McLellan GJ. Validation and comparison of four handheld tonometers in normal ex vivo canine eyes [published online ahead of print, 2020 Jun 1]. Vet Ophthalmol. 2020;10.1111/vop.12780. doi:10.1111/vop.12780
  3. Oikawa K, Ver Hoeve JN, Teixeira LBC, et al. Sub-region-Specific Optic Nerve Head Glial Activation in Glaucoma. Mol Neurobiol. 2020;57(6):2620-2638. doi:10.1007/s12035-020-01910-9
  4. Chan K, Hoon M, Pattnaik BR, et al. Vigabatrin-Induced Retinal Functional Alterations and Second-Order Neuron Plasticity in C57BL/6J Mice. Invest Ophthalmol Vis Sci. 2020;61(2):17. doi:10.1167/iovs.61.2.17
  5. Krishnan H, Hetzel S, McLellan GJ, Bentley E. Comparison of outcomes in cataractous eyes of dogs undergoing phacoemulsification versus eyes not undergoing surgery. Vet Ophthalmol. 2020;23(2):286-291. doi:10.1111/vop.12724
  6. Lewin AC, Coghill LM, McLellan GJ, Bentley E, Kousoulas KG. Genomic analysis for virulence determinants in feline herpesvirus type-1 isolates. Virus Genes. 2020;56(1):49-57. doi:10.1007/s11262-019-01718-3
  7. Heidari M, Radcliff AB, McLellan GJ, et al. Evoked potentials as a biomarker of remyelination [published online ahead of print, 2019 Dec 16]. Proc Natl Acad Sci U S A. 2019;116(52):27074-27083. doi:10.1073/pnas.1906358116
  8. Snyder KC, Oikawa K, Williams J, et al. Imaging Distal Aqueous Outflow Pathways in a Spontaneous Model of Congenital Glaucoma. Transl Vis Sci Technol. 2019;8(5):22. Published 2019 Oct 9. doi:10.1167/tvst.8.5.22
  9. Gloe S, Rothering A, Kiland JA, McLellan GJ. Validation of the Icare® TONOVET plus rebound tonometer in normal rabbit eyes. Exp Eye Res. 2019;185:107698. doi:10.1016/j.exer.2019.107698
  10. Bradfield Y, Barbosa T, Blodi B, et al. Comparative Intraoperative Anterior Segment OCT Findings in Pediatric Patients with and without Glaucoma. Ophthalmol Glaucoma. 2019;2(4):232-239. doi:10.1016/j.ogla.2019.04.006
  11. Beckwith-Cohen B, Hoffman A, McLellan GJ, Dubielzig RR. Feline Neovascular Vitreoretinopathy and Anterior Segment Dysgenesis With Concurrent Glaucoma in Domestic Cats. Vet Pathol. 2019;56(2):259-268. doi:10.1177/0300985818798087
  12. Telle MR, Chen N, Shinsako D, et al. Relationship between corneal sensitivity, corneal thickness, corneal diameter, and intraocular pressure in normal cats and cats with congenital glaucoma. Vet Ophthalmol. 2019;22(1):4-12. doi:10.1111/vop.12558
  13. McLellan, G.J., Kemmerling, J.P., Kiland, J.A. (2013) Validation of the TonoVet® Rebound Tonometer in Normal and Glaucomatous Cats.  Veterinary Ophthalmology. 16 (2), 111-118. PMID:22672669
  14. Teixeira, L.B.C., Buhr, K.A., Bowie, O., Duke, F.D., Nork, T.M., Dubielzig, R.R., McLellan, G.J. (2014)  Quantifying Optic Nerve Axons in a Cat Glaucoma Model by a Semi-Automated Targeted Counting Method Molecular Vision  20:376-85. PMID: 24715755
  15. McLellan, G.J. and Rasmussen, C.A. (2012) Optical Coherence Tomography for the Evaluation of Retina and Optic Nerve Morphology in Animal Subjects:  Practical Considerations. Veterinary Ophthalmology 15 Suppl 2:13-28 PMID: 22805095.
  16. Schallek, J., McLellan, G.J.,Viswanathan, S., Ts’o D. (2012) Retinal Intrinsic Optical Signals in a Cat Model of Primary Congenital Glaucoma Investigative Ophthalmology and Visual Science 53 (4), 1971-1981.  PMID:22395886
  17. McLellan, G.J. and Miller, P.E. (2011) Feline Glaucoma- A Comprehensive Review.  Veterinary Ophthalmology 14 (Suppl 1), 15-29. PMCID: PMC3348181