Ian Sigal, PhD

Assistant Professor of Ophthalmology; University of Pittsburgh School of Medicine

Contact

203 Lothrop Street, Suite 930
Pittsburgh, PA 15213
(412) 864‐2220
F: (412) 647‐5880

Dr. Sigal received a B.Sc. in Physics from the Universidad Nacional Autónoma de México, México City (1999), a M.A.Sc. in Aerospace Engineering from the University of Toronto, Canada (2001), and a Ph.D. in Mechanical Engineering (Collaborative program in Biomedical Engineering) also from the University of Toronto, Canada (2006). In graduate school Dr. Sigal developed computational techniques to model the differences in biomechanics between individuals, and understand why some develop complications while others do not. He continued this work as a post-doctoral fellow and then as a research associate at the Devers Eye Institute in Portland Oregon until joining the University of Pittsburgh on October 2010. Initial projects of the Laboratory of Ocular Biomechanics focus on methods to measure and predict long-term effects of altered ocular biomechanics, such as increased risk of glaucomatous vision loss. This will involve both computational and experimental techniques.

Selected Publications

2013
H Ishikawa, CL Chen, G Wollstein, J Grimm, Y Ling, RA Bilonick, IA Sigal, L Kagemann and JS Schuman, “High Dynamic Range Imaging Concept-Based Signal Enhancement Method Reduced the Optical Coherence Tomography (OCT) Measurement Variability”, Invest Ophthalmol Vis Sci, 54(1):836-841, Jan 2013. PMID 23299477.

2012
IA Sigal, JG Flanagan, KL Lathrop, I Tertinegg and R Bilonick, “Human lamina cribrosa insertion and age”. Invest Ophthalmol Vis Sci, 53(11):6870-6879, Oct 2012. PMID 22956611.
AW Francis, L Kagemann, G Wollstein, H Ishikawa, S Folz, D Overby, IA Sigal, B Wang and JS Schuman, “Morphometric Analysis of Aqueous Humor Outflow Structures with Spectral Domain Optical Coherence Tomography”. Invest Ophthalmol Vis Sci, 53(9):5198-5207, Aug 2012, PMID 22499987.
L Kagemann, G Wollstein, H Ishikawa, Z Nadler, IA Sigal, LS Folio and JS Schuman, “Visualization of the Conventional Outflow Pathway in the Living Human Eye”. Ophthalmology, 119:8:1563-1568, Aug 2012. PMID 22683063.
IA Sigal and JL Grimm, “A few good responses. Which mechanical effects of IOP on the ONH to study?”, Invest Ophthalmol Vis Sci, 53(7):4270-4278, Jun 2012. PMID 22570343.
IA Sigal, RA Bilonick, L Kagemann, G Wollstein, H Ishikawa, J Schuman and JL Grimm, “The optic nerve head as a robust biomechanical system”. Invest Ophthalmol Vis Sci, 53(6):2658-2667, May 2012. PMID 22427598.
R Grytz, IA Sigal, JW Ruberti, G Meschke and JC Downs, “Lamina cribrosa thickening in early glaucoma predicted by a microstructure motivated growth and remodeling approach”, Mechanics of Materials, Vol. 44:99-109, 2012. doi:10.1016/j.mechmat.2011.07.004.

2011
NG Strouthidis, B Fortune, H Yang, IA Sigal and CF Burgoyne, “The Effect of Acute Intraocular Pressure Elevation on the Monkey Optic Nerve Head As Detected by Spectral Domain Optical Coherence Tomography”. Invest Ophthalmol Vis Sci, 52(12):9431-37, Dec 2011. PMID 22058335.
IA Sigal, H Yang, MD Roberts, JL Grimm, CF Burgoyne, S Demirel and JC Downs, “IOP-induced lamina cribrosa displacement and scleral canal expansion. Are they independent or related?”. Invest Ophthalmol Vis Sci, 52(12):9023-32, Nov 2011. PMID 21989723.
L Kagemann, G Wollstein, H Ishikawa, IA Sigal, LS Folio, J Xu, H. Gong and JS Schuman, “3D visualization of aqueous outflow structures in-situ in humans”. Experimental Eye Research, 93(3): 308-315, Sep 2011. Camras Special Issue, PMID: 21514296.
H Yang, G Williams, JC Downs, IA Sigal, MD Roberts, H Thompson and CF Burgoyne. “Posterior (outward) migration of the lamina cribrosa and early cupping in monkey experimental glaucoma”. Invest Ophthalmol Vis Sci, 52(10):7109-21, Sep 2011. PMID 21715355.
JC Downs, MD Roberts and IA Sigal, “Glaucomatous cupping of the lamina cribrosa: a review of the evidence for active progressive remodeling as a mechanism”, Experimental Eye Research, 93(2):133-140, Aug 2011. PMID 20708001.
IA Sigal, “An applet to estimate the IOP-induced stress and strain within the optic nerve head”. Invest Ophthalmol Vis Sci. 52(8):5497-506, Jul 2011. PMID 21527378.
R Norman, JG Flanagan, IA Sigal, S Rausch, I Tertinegg and CR Ethier. “Finite element modeling of the human sclera: influence on optic nerve head biomechanics and connections with glaucoma”. Experimental Eye Research, 93(1):4-12, Jul 2011. PMID 20883693
IA Sigal, H Yang, MD Roberts, CF Burgoyne and JC Downs, “IOP-induced lamina cribrosa displacement and scleral canal expansion: an analysis of factor interactions using parameterized eye-specific models”, Invest Ophthalmol Vis Sci. 52(3):1896-1907, Mar 2011. PMID 20881292
NG Strouthidis, B Fortune, H Yang, IA Sigal and CF Burgoyne, “Longitudinal change detected by spectral domain optical coherence tomography in the glaucomatous optic nerve head and peripapillary retina”, Invest Ophthalmol Vis Sci. 52(3):1206-19, Mar 2011. PMID 21217108.
H Yang, H Thompson, MD Roberts, IA Sigal, JC Downs and CF Burgoyne. “Deformation of the early glaucomatous monkey optic nerve head connective tissue following acute IOP elevation within 3-D histomorphometric reconstructions”, Invest Ophthalmol Vis Sci, 52(1):345-63, Jan 2011. PMID 20702834.

2010
MD Roberts, IA Sigal, Y Liang, CF Burgoyne and JC Downs. “Changes in the biomechanical response of the optic nerve head in early experimental glaucoma”, Invest Ophthalmol Vis Sci. 51(11):5675-5684, Nov 2010. PMID 20538991.
PG Sanfilippo, A Cardini, IA Sigal, J Ruddle, BE Chua, AW Hewitt, and DA Mackey. “A geometric morphometric assessment of the optic cup in glaucoma”, Experimental Eye Research, 91(3): 405-414, Sep 2010. PMID 20599965.
R Norman, JG Flanagan, S Rausch, IA Sigal, I Tertinegg, A Eilaghi, S Portnoy, J Sled and CR Ethier. “Dimensions of the human sclera: thickness measurement and regional changes with axial length”, Experimental Eye Research, 90(2): 277-284, Feb 2010.
IA Sigal and CM Whyne. “Mesh morphing and response surface analysis: quantifying sensitivity of vertebral mechanical behaviour”, Annals of Biomedical Engineering, 38(1):41-56, Jan 2010.
IA Sigal, H Yang, MD Roberts and JC Downs. “Morphing methods to parameterize specimen-specific finite element model geometries”, Journal of Biomechanics, 43(2):254-262. 19, Jan 2010.
IA Sigal, JG Flanagan, I Tertinegg and CR Ethier, “3D morphometry of the human optic nerve head”, Experimental Eye Research, 90(1):70-80, Jan 2010.
MD Roberts, Yi Liang, IA Sigal, J Grimm, J Reynaud, A Bellezza, CF Burgoyne and JC Downs. “Correlation Between Local Stress and Strain and Lamina Cribrosa Connective Tissue Volume Fraction in Normal Monkey Eyes”, Invest Ophthalmol Vis Sci, 51(1):295-307, Jan 2010. PMID 19900442.

2009
H Yang, JC Downs, IA Sigal, M Roberts, H Thompson, CF Burgoyne. “Deformation of the normal monkey optic nerve head connective tissues following acute IOP elevation within 3-D histomorphometric reconstructions”, Invest Ophthalmol Vis Sci , 50(12): 5785-5789. Dec 2009. PMID 19628739.
IA Sigal. “Interactions between geometry and mechanical properties on the optic nerve head”, Invest Ophthalmol Vis Sci, 50(6): 2785-95. Jun 2009. PMID 19168906.
IA Sigal and CR Ethier. “Biomechanics of the optic nerve head”, Experimental Eye Research, 88(4):799-807, Apr 2009. PMID 19217902.
IA Sigal, JG Flanagan, I Tertinegg and CR Ethier. “Modeling individual-specific human optic nerve head biomechanics. Part II: Influence of material properties”, Biomech Model Mechanobiol, 8(2):99-109, Apr 2009. PMID 18301933.
IA Sigal, JG Flanagan, I Tertinegg and CR Ethier. “Modeling individual-specific human optic nerve head biomechanics. Part I: IOP-induced deformations and influence of geometry”, Biomech Model Mechanobiol, 8(2):85-98, Apr 2009. PMID 18309526.

2008 and earlier
IA Sigal, MR Hardisty and CM Whyne. “Mesh-morphing algorithms for specimen-specific finite element modeling”, J Biomech, 41(7):1381-1389, 2008. PMID 18397789.
IA Sigal, JG Flanagan, I Tertinegg and CR Ethier. “Predicted extension, compression and shearing of optic nerve head tissues”, Experimental Eye Research, 85(3):312-322, Sep 2007. PMID 17624325.
IA Sigal, JG Flanagan, I Tertinegg and CR Ethier, “Factors Influencing Human Optic Nerve Head Biomechanics”, Invest Ophthalmol Vis Sci, 46(11): 4189-4199, Nov 2005. PMID 16249498.
IA Sigal, JG Flanagan, I Tertinegg and CR Ethier. “Reconstruction of Human Optic Nerve Heads for Finite Element Modeling”, Technology and Health Care: Official Journal of the European Society for Engineering and Medicine, 13(4): 313-329, Aug 2005. PMID 16055979.
IA Sigal, JG Flanagan, I Tertinegg and CR Ethier. “Finite Element Modeling of Optic Nerve Head Biomechanics”, Invest Ophthalmol Vis Sci, 45(12): 4378-4387, Dec 2004. PMID 15557446.
IL Garzón, JA Reyes-Nava, JI Rodríguez-Hernández, I Sigal, MR Beltrán and K Michaelian. “Chirality in Bare and Passivated Gold Nanoclusters”, Phys. Rev. B 66(7), 073403, Aug 2002.