Michael A. Speidel

Credentials: PhD

Position title: Associate Professor, Medical Physics
Technical Director, UWHC Cardiac Catheterization Laboratory
Co-Vice Chair of Education

Email: speidel@wisc.edu

Phone: 608-263-6795

1177 Wisconsin Institutes for Medical Research
Michael Speidel is a primary advisor in the Department of Medical Physics.


B.A. Physics, University of Wisconsin, Madison, WI

M.S. Medical Physics, University of Wisconsin, Madison, WI

Ph.D. Medical Physics, University of Wisconsin, Madison, WI

Department Affilations

Medical Physics



  • Assistant Professor, Departments of Medical Physics and Medicine
  • Technical Director, Cardiac Catheterization Laboratory, UW Hospital and Clinics

Research Interests

  • X-ray fluoroscopy and angiography
  • Device guidance during cardiac interventions
  • Dose reduction
  • Scanning-beam digital x-ray (SBDX) technology


  • Bodart LE, Ciske BR, Le J, Reilly NM, Deaño RC, Ewer SM, Tipnis P, Rahko PS, Wagner MG, Raval AN, Speidel MA. Technical and clinical study of x-ray-based surface echo probe tracking using an attached fiducial apparatus. Med Phys. 2021 May;48(5):2528-2542. doi: 10.1002/mp.14790. Epub 2021 Mar 25. PubMed PMID: 33608930; NIHMSID:NIHMS1700768.
  • Pravdivtseva MS, Gaidzik F, Berg P, Hoffman C, Rivera-Rivera LA, Medero R, Bodart L, Roldan-Alzate A, Speidel MA, Johnson KM, Wieben O, Jansen O, Hövener JB, Larsen N. Pseudo-Enhancement in Intracranial Aneurysms on Black-Blood MRI: Effects of Flow Rate, Spatial Resolution, and Additional Flow Suppression. J Magn Reson Imaging. 2021 Mar 10;. doi: 10.1002/jmri.27587. [Epub ahead of print] PubMed PMID: 33694334.
  • Periyasamy S, Hoffman CA, Longhurst C, Schefelker GC, Ozkan OS, Speidel MA, Laeseke PF. A Quantitative Digital Subtraction Angiography Technique for Characterizing Reduction in Hepatic Arterial Blood Flow During Transarterial Embolization. Cardiovasc Intervent Radiol. 2021 Feb;44(2):310-317. doi: 10.1007/s00270-020-02640-0. Epub 2020 Oct 6. PubMed PMID: 33025244; PubMed Central PMCID: PMC7855448.
  • Hoffman C, Periyasamy S, Longhurst C, Medero R, Roldan-Alzate A, Speidel MA, Laeseke PF. A technique for intra-procedural blood velocity quantitation using time-resolved 2D digital subtraction angiography. CVIR Endovasc. 2021 Jan 7;4(1):11. doi: 10.1186/s42155-020-00199-y. PubMed PMID: 33411087; PubMed Central PMCID: PMC7790988.
  • Ruedinger KL, Schafer S, Speidel MA, Strother CM. 4D-DSA: Development and Current Neurovascular Applications. AJNR Am J Neuroradiol. 2021 Jan;42(2):214-220. doi: 10.3174/ajnr.A6860. Epub 2020 Nov 26. Review. PubMed PMID: 33243899; PubMed Central PMCID: PMC7872169.
  • Wagner MG. Real-Time Thinning Algorithms for 2D and 3D Images using GPU processors. J Real Time Image Process. 2020 Oct 28;17(5):1255-1266. doi: 10.1007/s11554-019-00886-7. Epub 2019 May 28. PubMed PMID: 33737980; PubMed Central PMCID: PMC7962620.
  • Meram E, Shaughnessy G, Longhurst C, Hoffman C, Wagner M, Mistretta CA, Speidel MA, Laeseke PF. Optimization of quantitative time-resolved 3D (4D) digital subtraction angiography in a porcine liver model. Eur Radiol Exp. 2020 Jul 2;4(1):37. doi: 10.1186/s41747-020-00164-3. PubMed PMID: 32613472; PubMed Central PMCID: PMC7329977.
  • Ruedinger KL, Harvey EC, Schafer S, Speidel MA, Strother CM. Optimizing the Quality of 4D-DSA Temporal Information. AJNR Am J Neuroradiol. 2019 Dec;40(12):2124-2129. doi: 10.3174/ajnr.A6290. Epub 2019 Oct 31. PubMed PMID: 31672837; PubMed Central PMCID: PMC6975361.
  • Lamers LJ, Morray BH, Nugent A, Speidel M, Suntharos P, Prieto L. Multicenter Assessment of Radiation Exposure during Pediatric Cardiac Catheterizations Using a Novel Imaging System. J Interv Cardiol. 2019;2019:7639754. doi: 10.1155/2019/7639754. eCollection 2019. PubMed PMID: 32089654; PubMed Central PMCID: PMC7012227.
  • Meram E, Harari C, Shaughnessy G, Wagner M, Brace CL, Mistretta CA, Speidel MA, Laeseke PF. Quantitative 4D-Digital Subtraction Angiography to Assess Changes in Hepatic Arterial Flow during Transarterial Embolization: A Feasibility Study in a Swine Model. J Vasc Interv Radiol. 2019 Aug;30(8):1286-1292. doi: 10.1016/j.jvir.2019.01.018. Epub 2019 Jun 1. PubMed PMID: 31160194.
  • Speidel MA, Burton CS, Nikolau EP, Schafer S, Laeseke PF. Prototype system for interventional dual-energy subtraction angiography. Proc SPIE Int Soc Opt Eng. 2019 Feb;10951. doi: 10.1117/12.2512956. Epub 2019 Mar 8. PubMed PMID: 32669753; PubMed Central PMCID: PMC7362684.
  • Shaughnessy G, Schafer S, Speidel MA, Strother CM, Mistretta CA. Measuring blood velocity using 4D-DSA: A feasibility study. Med Phys. 2018 Oct;45(10):4510-4518. doi: 10.1002/mp.13120. Epub 2018 Sep 6. PubMed PMID: 30102773; PubMed Central PMCID: PMC6767933.
  • Wu Y, Shaughnessy G, Hoffman CA, Oberstar EL, Schafer S, Schubert T, Ruedinger KL, Davis BJ, Mistretta CA, Strother CM, Speidel MA. Quantification of Blood Velocity with 4D Digital Subtraction Angiography Using the Shifted Least-Squares Method. AJNR Am J Neuroradiol. 2018 Oct;39(10):1871-1877. doi: 10.3174/ajnr.A5793. Epub 2018 Sep 13. PubMed PMID: 30213811; PubMed Central PMCID: PMC6177311.
  • Li Y, Speidel MA, Francois CJ, Chen GH. Radiation Dose Reduction in CT Myocardial Perfusion Imaging Using SMART-RECON. IEEE Trans Med Imaging. 2017 Dec;36(12):2557-2568. doi: 10.1109/TMI.2017.2747521. Epub 2017 Aug 30. PubMed PMID: 28866488.
  • Dunkerley DAP, Slagowski JM, Funk T, Speidel MA. Dynamic electronic collimation method for 3-D catheter tracking on a scanning-beam digital x-ray system. J Med Imaging (Bellingham). 2017 Apr;4(2):023501. doi: 10.1117/1.JMI.4.2.023501. Epub 2017 Apr 18. PubMed PMID: 28439521; PubMed Central PMCID: PMC5394503.
  • Sandoval-Garcia C, Yang P, Schubert T, Schafer S, Hetzel S, Ahmed A, Strother C. Comparison of the Diagnostic Utility of 4D-DSA with Conventional 2D- and 3D-DSA in the Diagnosis of Cerebrovascular Abnormalities. AJNR Am J Neuroradiol. 2017 Apr;38(4):729-734. doi: 10.3174/ajnr.A5137. Epub 2017 Mar 9. PubMed PMID: 28279986; PubMed Central PMCID: PMC5389915.
  • Slagowski JM, Dunkerley DAP, Hatt CR, Speidel MA. Single-view geometric calibration for C-arm inverse geometry CT. J Med Imaging (Bellingham). 2017 Jan;4(1):013506. doi: 10.1117/1.JMI.4.1.013506. Epub 2017 Mar 20. PubMed PMID: 28560241; PubMed Central PMCID: PMC5358550.
  • Speidel MA, Slagowski JM, Dunkerley DAP, Wagner M, Funk T, Raval AN. Localization of cardiac volume and patient features in inverse geometry x-ray fluoroscopy. Proc SPIE Int Soc Opt Eng. 2017 Feb;10132. doi: 10.1117/12.2254400. Epub 2017 Mar 9. PubMed PMID: 28943697; PubMed Central PMCID: PMC5606251.
  • Dunkerley DAP, Slagowski JM, Bodart LE, Speidel MA. Automated 3D coronary sinus catheter detection using a scanning-beam digital x-ray system. Proc SPIE Int Soc Opt Eng. 2017 Feb;10132. doi: 10.1117/12.2254443. Epub 2017 Mar 9. PubMed PMID: 28943696; PubMed Central PMCID: PMC5606249.
  • Buehler M, Slagowski JM, Mistretta CA, Strother CM, Speidel MA. 4D DSA reconstruction using tomosynthesis projections. Proc SPIE Int Soc Opt Eng. 2017 Feb;10132. doi: 10.1117/12.2255197. Epub 2017 Mar 9. PubMed PMID: 28943698; PubMed Central PMCID: PMC5606252.
  • Oberstar EL, Speidel MA, Davis BJ, Strother CM, Mistretta CA. Feasibility of reduced-dose three-dimensional/four-dimensional-digital subtraction angiogram using a weighted edge preserving filter. J Med Imaging (Bellingham). 2017 Jan;4(1):013501. doi: 10.1117/1.JMI.4.1.013501. Epub 2017 Jan 11. PubMed PMID: 28097212; PubMed Central PMCID: PMC5225403.
  • Hatt CR, Speidel MA, Raval AN. Real-time pose estimation of devices from x-ray images: Application to x-ray/echo registration for cardiac interventions. Med Image Anal. 2016 Dec;34:101-108. doi: 10.1016/j.media.2016.04.008. Epub 2016 May 3. PubMed PMID: 27179366; PubMed Central PMCID: PMC5048559.
  • Dunkerley DA, Funk T, Speidel MA. Method for dose-reduced 3D catheter tracking on a scanning-beam digital x-ray system using dynamic electronic collimation. Proc SPIE Int Soc Opt Eng. 2016 Feb 27;9783. doi: 10.1117/12.2216892. Epub 2016 Mar 25. PubMed PMID: 27375314; PubMed Central PMCID: PMC4925103.
  • Slagowski JM, Dunkerley DA, Hatt CR, Speidel MA. A geometric calibration method for inverse geometry computed tomography using P-matrices. Proc SPIE Int Soc Opt Eng. 2016 Feb 27;9783. doi: 10.1117/12.2216565. Epub 2016 Mar 22. PubMed PMID: 27375313; PubMed Central PMCID: PMC4925097.
  • Sandoval-Garcia C, Royalty K, Yang P, Niemann D, Ahmed A, Aagaard-Kienitz B, Başkaya MK, Schafer S, Strother C. 4D DSA a new technique for arteriovenous malformation evaluation: a feasibility study. J Neurointerv Surg. 2016 Mar;8(3):300-4. doi: 10.1136/neurintsurg-2014-011534. Epub 2015 Jan 12. PubMed PMID: 25583531; PubMed Central PMCID: PMC4740248.
  • Wagner M, Schafer S, Strother C, Mistretta C. 4D interventional device reconstruction from biplane fluoroscopy. Med Phys. 2016 Mar;43(3):1324-34. doi: 10.1118/1.4941950. PubMed PMID: 26936717; PubMed Central PMCID: PMC4760973.
  • Hatt CR, Wagner M, Raval AN, Speidel MA. Dynamic tracking of prosthetic valve motion and deformation from bi-plane x-ray views: feasibility study. Proc SPIE Int Soc Opt Eng. 2016;9786. doi: 10.1117/12.2216588. PubMed PMID: 28008211; PubMed Central PMCID: PMC5166601.
  • Hatt CR, Tomkowiak MT, Dunkerley DA, Slagowski JM, Funk T, Raval AN, Speidel MA. Depth-resolved registration of transesophageal echo to x-ray fluoroscopy using an inverse geometry fluoroscopy system. Med Phys. 2015 Dec;42(12):7022-33. doi: 10.1118/1.4935534. PubMed PMID: 26632057; PubMed Central PMCID: PMC4644157.
  • Wagner M, Yang P, Schafer S, Strother C, Mistretta C. Noise reduction for curve-linear structures in real time fluoroscopy applications using directional binary masks. Med Phys. 2015 Aug;42(8):4645-53. doi: 10.1118/1.4924266. PubMed PMID: 26233192; PubMed Central PMCID: PMC4506298.
  • Dunkerley DA, Tomkowiak MT, Slagowski JM, McCabe BP, Funk T, Speidel MA. Monte Carlo simulation of inverse geometry x-ray fluoroscopy using a modified MC-GPU framework. Proc SPIE Int Soc Opt Eng. 2015 Feb 21;9412. doi: 10.1117/12.2081684. PubMed PMID: 26113765; PubMed Central PMCID: PMC4476537.
  • Slagowski JM, Tomkowiak MT, Dunkerley DA, Speidel MA. Feasibility of CT-based 3D anatomic mapping with a scanning-beam digital x-ray (SBDX) system. Proc SPIE Int Soc Opt Eng. 2015;9412. doi: 10.1117/12.2082052. PubMed PMID: 26236072; PubMed Central PMCID: PMC4517620.
  • Speidel MA, Tomkowiak MT, Raval AN, Dunkerley DA, Slagowski JM, Kahn P, Ku J, Funk T. Detector, collimator and real-time reconstructor for a new scanning-beam digital x-ray (SBDX) prototype. Proc SPIE Int Soc Opt Eng. 2015;9412. doi: 10.1117/12.2081716. PubMed PMID: 26236071; PubMed Central PMCID: PMC4517476.
  • Tomkowiak MT, Raval AN, Van Lysel MS, Funk T, Speidel MA. Calibration-free coronary artery measurements for interventional device sizing using inverse geometry x-ray fluoroscopy: in vivo validation. J Med Imaging (Bellingham). 2014 Oct;1(3). doi: 10.1117/1.JMI.1.3.033504. PubMed PMID: 25544948; PubMed Central PMCID: PMC4275130.
  • Tao Y, Chen GH, Hacker TA, Raval AN, Van Lysel MS, Speidel MA. Low dose dynamic CT myocardial perfusion imaging using a statistical iterative reconstruction method. Med Phys. 2014 Jul;41(7):071914. doi: 10.1118/1.4884023. PubMed PMID: 24989392; PubMed Central PMCID: PMC4105971.
  • Tomkowiak MT, Raval AN, Van Lysel MS, Funk T, Speidel MA. Calibration-Free Coronary Artery Measurements for Interventional Device Sizing using Inverse Geometry X-ray Fluoroscopy: In Vivo Validation. Proc SPIE Int Soc Opt Eng. 2014 Mar 19;9033:90332H. doi: 10.1117/12.2044078. PubMed PMID: 24999298; PubMed Central PMCID: PMC4079058.
  • Burion S, Speidel MA, Funk T. A real-time regional adaptive exposure method for saving dose-area product in x-ray fluoroscopy. Med Phys. 2013 May;40(5):051911. doi: 10.1118/1.4801908. PubMed PMID: 23635281; PubMed Central PMCID: PMC3651207.
  • Tomkowiak MT, Van Lysel MS, Speidel MA. Monoplane Stereoscopic Imaging Method for Inverse Geometry X-ray Fluoroscopy. Proc SPIE Int Soc Opt Eng. 2013 Mar 13;8669. doi: 10.1117/12.2006238. PubMed PMID: 24392204; PubMed Central PMCID: PMC3877327.
  • Speidel MA, Bateman CL, Tao Y, Raval AN, Hacker TA, Reeder SB, Van Lysel MS. Reduction of image noise in low tube current dynamic CT myocardial perfusion imaging using HYPR processing: a time-attenuation curve analysis. Med Phys. 2013 Jan;40(1):011904. doi: 10.1118/1.4770283. PubMed PMID: 23298095; PubMed Central PMCID: PMC3537716.
  • Klein AJ, Tomkowiak MT, Vigen KK, Hacker TA, Speidel MA, Vanlysel MS, Shah N, Raval AN. Multimodality image fusion to guide peripheral artery chronic total arterial occlusion recanalization in a swine carotid artery occlusion model: unblinding the interventionalist. Catheter Cardiovasc Interv. 2012 Dec 1;80(7):1090-8. doi: 10.1002/ccd.24391. Epub 2012 Oct 24. PubMed PMID: 23097307; PubMed Central PMCID: PMC3518624.
  • Lauzier PT, Tang J, Speidel MA, Chen GH. Noise spatial nonuniformity and the impact of statistical image reconstruction in CT myocardial perfusion imaging. Med Phys. 2012 Jul;39(7):4079-92. doi: 10.1118/1.4722983. PubMed PMID: 22830741; PubMed Central PMCID: PMC3382258.
  • Speidel MA, Wilfley BP, Hsu A, Hristov D. Feasibility of low-dose single-view 3D fiducial tracking concurrent with external beam delivery. Med Phys. 2012 Apr;39(4):2163-9. doi: 10.1118/1.3697529. PubMed PMID: 22482637; PubMed Central PMCID: PMC3326074.
  • Tomkowiak MT, Klein AJ, Vigen KK, Hacker TA, Speidel MA, VanLysel MS, Raval AN. Targeted transendocardial therapeutic delivery guided by MRI-x-ray image fusion. Catheter Cardiovasc Interv. 2011 Sep 1;78(3):468-78. doi: 10.1002/ccd.22901. Epub 2011 Mar 16. PubMed PMID: 21413125.
  • McCabe BP, Speidel MA, Pike TL, Van Lysel MS. Calibration of GafChromic XR-RV3 radiochromic film for skin dose measurement using standardized x-ray spectra and a commercial flatbed scanner. Med Phys. 2011 Apr;38(4):1919-30. doi: 10.1118/1.3560422. PubMed PMID: 21626925; PubMed Central PMCID: PMC3078021.
  • Tomkowiak MT, Speidel MA, Raval AN, Van Lysel MS. Calibration-free device sizing using an inverse geometry x-ray system. Med Phys. 2011 Jan;38(1):283-93. doi: 10.1118/1.3528227. PubMed PMID: 21361197; PubMed Central PMCID: PMC3021558.
  • Speidel MA. Inverse geometry x-ray imaging: application in interventional procedures. J Am Coll Radiol. 2011 Jan;8(1):74-7. doi: 10.1016/j.jacr.2010.11.002. PubMed PMID: 21211771; PubMed Central PMCID: PMC3021476.
  • Speidel MA, Tomkowiak MT, Raval AN, Van Lysel MS. Three-dimensional tracking of cardiac catheters using an inverse geometry x-ray fluoroscopy system. Med Phys. 2010 Dec;37(12):6377-89. doi: 10.1118/1.3515463. PubMed PMID: 21302795; PubMed Central PMCID: PMC3003720.
  • Nett BE, Leng S, Zambelli JN, Reeder SB, Speidel MA, Chen GH. Temporally targeted imaging method applied to ECG-gated computed tomography: preliminary phantom and in vivo experience. Acad Radiol. 2008 Jan;15(1):93-106. doi: 10.1016/j.acra.2007.07.003. PubMed PMID: 18078912; PubMed Central PMCID: PMC2693077.
  • Speidel MA, Wilfley BP, Star-Lack JM, Heanue JA, Betts TD, Van Lysel MS. Comparison of entrance exposure and signal-to-noise ratio between an SBDX prototype and a wide-beam cardiac angiographic system. Med Phys. 2006 Aug;33(8):2728-43. doi: 10.1118/1.2198198. PubMed PMID: 16964848.
  • Speidel MA, Wilfley BP, Star-Lack JM, Heanue JA, Van Lysel MS. Scanning-beam digital x-ray (SBDX) technology for interventional and diagnostic cardiac angiography. Med Phys. 2006 Aug;33(8):2714-27. doi: 10.1118/1.2208736. PubMed PMID: 16964847.
  • Cao H, Speidel MA, Tsai JZ, Van Lysel MS, Vorperian VR, Webster JG. FEM analysis of predicting electrode-myocardium contact from RF cardiac catheter ablation system impedance. IEEE Trans Biomed Eng. 2002 Jun;49(6):520-6. doi: 10.1109/TBME.2002.1001965. PubMed PMID: 12046696.
  • Speidel MA, Wilfley BP, Heanue JA, Betts TD, Van Lysel MS. Comparison of vessel contrast measured with a scanning-beam digital x-ray system and an image intensifier/television system. Med Phys. 2001 Feb;28(2):232-40. doi: 10.1118/1.1339881. PubMed PMID: 11243348.


  • American Association of Physicists in Medicine