A system that produces stacks of successive, high-quality, 2D images - perfectly aligned to easily create superbly detailed 3D models.



No collection, registration or staining!

Individual sections do not need to be collected, registered or stained, allowing for rapid imaging of samples. E.g. Sectioning an E14.5 mouse embryo at 3 microns would produce around 3,500 images in 8 hours!

No clearing required!



Constant resolution through sample depth

Sections can be cut as thin as 1 μm, which results in 3D models with a typical voxel resolutions of 1-8 μm3. This resolution enables identification of blood vessels and nerves, often not visible using lower-resolution techniques such as optical projection tomography (OPT), micro-magnetic resonance imaging (μMRI) or micro-computed tomography (μCT).


No sample distortion

Sample sizes up to 30 mm

Samples are embedded in a hard plastic resin that enables sections from 1 - 10 microns to be accurately removed.


Optical imaging

Flexible, optical-based system

A felixible, optical-based system, suitable for use over a broad range of magnifications that can be configured for multiple fluorescent channels.



Most tissue types and bone possible

Used in laboratories world-wide for 3D imaging of mouse embryos, embryonic organs, different tissue types and even plants.


Alternate views

Orthogonal and oblique views

Image data produced can be used to calculate orthogonal and oblique views of the tissue sample, with little resolution lost. These views can provide important additional information about sample morphology.

Realistic pricing for a high-performance sectioning system

Customer 3Ds

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The technique



After preparation, samples are embedded in a plastic resin that has been made highly fluorescent by the addition of dyes, so opaque and translucent tissue is imaged by suppressing the fluorescence. This results in excellent quality, high resolution images of the block surface, irrespective of the tissue type or developmental stage - different tissue types are easily distinguishable.


Sequential imaging

Once embedded, samples are sequentially imaged at a section thickness of 1-10 microns. Images are captured at the block surface, a section is removed, and the process repeated.



Image data can subsequently be imported directly into 2D or 3D visualisation software for analysis.

Further information

  • DMDD - Deciphering the Mechanisms of Developmental Disorders
    • Francis Cricick Institute, London
    • the DMDD website provides thousands of examples of HREM imaging, and also details the methods they used
  • Department of Physiology, Anatomy and Genetics
    • University of Oxford
  • UCL Centre for Advanced Biomedical Imaging (CABI)
    • London
  • Institute of Animal Science
    • ​Poultry and Aquaculture Sci. Dept.​
    • The Volcani Center,Israel
  • Therapeutic Target Discovery, Regeneron Pharmaceuticals
    • New York
  • Dept of Genetics & Evolution
    • University of Geneva
  • Developmental Biology, School of Life Sciences
    • University of Nottingham
  • Department of Basic Medical Sciences
    • Westlake Institute for Advanced study
    • Hangzhou, China
  • Division of Anatomy
    • Center for Anatomy & Cell Biology
    • Vienna
  1. Pokhrel, N., E. Ben-Tal Cohen, O. Genin, D. Sela-Donenfeld and Y. Cinnamon
    Cellular and morphological characterization of blastoderms from freshly laid broiler eggs.
    Poult Sci, 2017 PubMed abstract
  2. Zhou, Z., J. Wang, C. Guo, W. Chang, J. Zhuang, P. Zhu, and X. Li
    Temporally Distinct Six2-Positive Second Heart Field Progenitors Regulate Mammalian Heart
    Development and Disease Cell Rep, 2017. 18(4), 1019-1032 PubMed abstract
  3. Le Garrec, J.F., J.N. Dominguez, A. Desgrange, K.D. Ivanovitch, E. Raphael, J.A. Bangham, M. Torres, E. Coen, T.J. Mohun, and S.M. Meilhac
    A predictive model of asymmetric morphogenesis from 3D reconstructions of mouse heart looping dynamics.
    Elife, 2017. 6 PubMed abstract
  4. Geyer, S.H., L.F. Reissig, M. Husemann, C. Hofle, R. Wilson, F. Prin, D. Szumska, A. Galli, D.J. Adams, J. White, T.J. Mohun, and W.J. Weninger
    Morphology, topology and dimensions of the heart and arteries of genetically normal and mutant mouse embryos at stages S21-S23.
    J Anat, 2017. 231(4): 600-614 PubMed abstract
  5. Geyer, S.H., L. Reissig, J. Rose, R. Wilson, F. Prin, D. Szumska, R. Ramirez-Solis, C. Tudor, J. White, T.J. Mohun, and W.J. Weninger
    A staging system for correct phenotype interpretation of mouse embryos harvested on embryonic day 14 (E14.5). J Anat, 2017. 230(5): 710-719 PubMed abstract
  6. Geyer, S.H., B. Maurer-Gesek, L.F. Reissig and W.J. Weninger
    High-resolution Episcopic Microscopy (HREM) - Simple and Robust Protocols for Processing and Visualizing Organic Materials.
    J Vis Exp, 2017(125) PubMed abstract
  7. Anderson, R.H., B. Jensen, T.J. Mohun, S.E. Petersen, N. Aung, F. Zemrak, R.N. Planken, and D.H. MacIver
    Key Questions Relating to Left Ventricular Noncompaction Cardiomyopathy: Is the Emperor Still Wearing Any Clothes?
    Can J Cardiol, 2017. 33(6): p. 747-757 PubMed abstract
  8. Aiello, V.D., D.E. Spicer, R.H. Anderson, N.A. Brown and T.J. Mohun
    The independence of the infundibular building blocks in the setting of double-outlet right ventricle.
    Cardiol Young, 2017. 27(5): p. 825-836 PubMed abstract
  9. Zak, J., V. Vives, D. Szumska, A. Vernet, J.E. Schneider, P. Miller, E.A. Slee, S. Joss, Y. Lacassie, E. Chen, L.F. Escobar, M. Tucker, A.S. Aylsworth, H.A. Dubbs, A.T. Collins, J. Andrieux, A. Dieux-Coeslier, E. Haberlandt, D. Kotzot, D.A. Scott, M.J. Parker, Z. Zakaria, Y.S. Choy, D. Wieczorek, A.M. Innes, K.R. Jun, S. Zinner, F. Prin, C.A. Lygate, P. Pretorius, J.A. Rosenfeld, T.J. Mohun, and X. Lu
    = ASPP2 deficiency causes features of 1q41q42 microdeletion syndrome.
    Cell Death Differ, 2016. 23(12): p. 1973-1984 PubMed abstract
  10. Wilson, R., S.H. Geyer, L. Reissig, J. Rose, D. Szumska, E. Hardman, F. Prin, C. McGuire, R. Ramirez-Solis, J. White, A. Galli, C. Tudor, E. Tuck, C. Mazzeo, J.C. Smith, E. Robertson, D.J. Adams, T. Mohun, and W.J. Weninger
    Highly variable penetrance of abnormal phenotypes in embryonic lethal knockout mice. Wellcome Open Res, 2016. 1: p. 1 PubMed abstract
  11. Lana-Elola, E., S. Watson-Scales, A. Slender, D. Gibbins, A. Martineau, C. Douglas, T. Mohun, E.M. Fisher, and V. Tybulewicz
    Genetic dissection of Down syndrome- associated congenital heart defects using a new mouse mapping panel.
    Elife, 2016. 5. (https://www.ncbi.nlm.nih.gov/pubmed/26765563">PubMed abstract
  12. Huang, Y.C., F. Chen and X. Li
    Clarification of mammalian cloacal morphogenesis using high-resolution episcopic microscopy.
    Dev Biol, 2016. 409(1): p. 106-13. PubMed abstract
  13. Henkelman, R.M., M. Friedel, J.P. Lerch, R. Wilson and T. Mohun
    Comparing homologous microscopic sections from multiple embryos using HREM.
    Dev Biol, 2016. 415(1): p. 1-5. PubMed abstract
  14. Dickinson, M.E., A.M. Flenniken, X. Ji, L. Teboul, M.D. Wong, J.K. White, T.F. Meehan, W.J. Weninger, H. Westerberg, H. Adissu, C.N. Baker, L. Bower, J.M. Brown, L.B. Caddle, F. Chiani, D. Clary, J. Cleak, M.J. Daly, J.M. Denegre, B. Doe, M.E. Dolan, S.M. Edie, H. Fuchs, V. Gailus-Durner, A. Galli, A. Gambadoro, J. Gallegos, S. Guo, N.R. Horner, C.W. Hsu, S.J. Johnson, S. Kalaga, L.C. Keith, L. Lanoue, T.N. Lawson, M. Lek, M. Mark, S. Marschall, J. Mason, M.L. McElwee, S. Newbigging, L.M. Nutter, K.A. Peterson, R. Ramirez-Solis, D.J. Rowland, E. Ryder, K.E. Samocha, J.R. Seavitt, M. Selloum, Z. Szoke-Kovacs, M. Tamura, A.G. Trainor, I. Tudose, S. Wakana, J. Warren, O. Wendling, D.B. West, L. Wong, A. Yoshiki, C. International Mouse Phenotyping, L. Jackson, I.C.d.l.S. Infrastructure Nationale Phenomin, L. Charles River, M.R.C. Harwell, P. Toronto Centre for, I. Wellcome Trust Sanger, R.B. Center, D.G. MacArthur, G.P. Tocchini-Valentini, X. Gao, P. Flicek, A. Bradley, W.C. Skarnes, M.J. Justice, H.E. Parkinson, M. Moore, S. Wells, R.E. Braun, K.L. Svenson, M.H. de Angelis, Y. Herault, T. Mohun, A.M. Mallon, R.M. Henkelman, S.D. Brown, D.J. Adams, K.C. Lloyd, C. McKerlie, A.L. Beaudet, M. Bucan, and S.A. Murray
    High-throughput discovery of novel developmental phenotypes.
    Nature, 2016. 537(7621): p. 508-514. PubMed abstract
  15. Captur, G., R. Wilson, M.F. Bennett, G. Luxan, A. Nasis, J.L. de la Pompa, J.C. Moon, and T.J. Mohun
    Morphogenesis of myocardial trabeculae in the mouse embryo.
    J Anat, 2016. 229(2): p. 314-25. PubMed abstract
  16. Anderson, R.H., S. Mori, D.E. Spicer, N.A. Brown and T.J. Mohun
    Development and Morphology of the Ventricular Outflow Tracts.
    World J Pediatr Congenit Heart Surg, 2016. 7(5): p. 561-77. PubMed abstract
  17. Anderson, R.H., N.A. Brown and T.J. Mohun
    Insights regarding the normal and abnormal formation of the atrial and ventricular septal structures.
    Clin Anat, 2016. 29(3): p. 290-304. PubMed abstract
  18. Spicer, D.E., D.J. Henderson, B. Chaudhry, T.J. Mohun and R.H. Anderson
    The anatomy and development of normal and abnormal coronary arteries.
    Cardiol Young, 2015. 25(8): p. 1493-503. PubMed abstract
  19. Notari, M., Y. Hu, G. Sutendra, Z. Dedeic, M. Lu, L. Dupays, A. Yavari, C.A. Carr, S. Zhong, A. Opel, A. Tinker, K. Clarke, H. Watkins, D.J. Ferguson, D.P. Kelsell, S. de Noronha, M.N. Sheppard, M. Hollinshead, T.J. Mohun, and X. Lu
    iASPP, a previously unidentified regulator of desmosomes, prevents arrhythmogenic right ventricular cardiomyopathy (ARVC)-induced sudden death.
    Proc Natl Acad Sci USA, 2015. 112(9): p. E973-81. PubMed abstract
  20. Matsui, H., S.Y. Ho, T.J. Mohun and H.M. Gardiner
    Postmortem high-resolution episcopic microscopy (HREM) of small human fetal hearts.
    Ultrasound Obstet Gynecol, 2015. 45(4): p. 492-3. PubMed abstract
  21. Geyer, S.H., I.E. Tinhofer, D.B. Lumenta, L.P. Kamolz, L. Branski, C.C. Finnerty, D.N. Herndon, and W.J. Weninger
    High-resolution episcopic microscopy (HREM): a useful technique for research in wound care.
    Ann Anat, 2015. 197: p. 3-10. PubMed abstract
  22. Dupays, L., C. Shang, R. Wilson, S. Kotecha, S. Wood, N. Towers, and T. Mohun
    Sequential Binding of MEIS1 and NKX2-5 on the Popdc2 Gene: A Mechanism for Spatiotemporal Regulation of Enhancers during Cardiogenesis.
    Cell Rep, 2015. 13(1): p. 183-195. PubMed abstract
  23. Bharucha, T., D.E. Spicer, T.J. Mohun, D. Black, G.W. Henry, and R.H. Anderson
    Cor triatriatum or divided atriums: which approach provides the better understanding?
    Cardiol Young, 2015. 25(2): p. 193-207. PubMed abstract
  24. Bailliard, F., D.E. Spicer, T.J. Mohun, G.W. Henry and R.H. Anderson
    The problems that exist when considering the anatomic variability between the channels that permit interventricular shunting.
    Cardiol Young, 2015. 25(1): p. 15-28. PubMed abstract
  25. Anderson, R.H., D.E. Spicer, G.W. Henry, C. Rigsby, A.M. Hlavacek, and T.J. Mohun
    What is aortic overriding?
    Cardiol Young, 2015. 25(4): p. 612-25. PubMed abstract
  26. Anderson, R.H., T.J. Mohun and N.A. Brown
    Clarifying the morphology of the ostium primum defect.
    J Anat, 2015. 226(3): p. 244-57. PubMed abstract
  27. Weninger, W.J., S.H. Geyer, A. Martineau, A. Galli, D.J. Adams, R. Wilson, and T.J. Mohun, Phenotyping structural abnormalities in mouse embryos using high-resolution episcopic microscopy.
    Dis Model Mech, 2014. 7(10): p. 1143-52. PubMed abstract
  28. Spicer, D.E., J.M. Bridgeman, N.A. Brown, T.J. Mohun and R.H. Anderson, The anatomy and development of the cardiac valves.
    Cardiol Young, 2014. 24(6): p. 1008-22. PubMed abstract
  29. Rochais, F., R. Sturny, C.M. Chao, K. Mesbah, M. Bennett, T.J. Mohun, S. Bellusci, and R.G. Kelly, FGF10 promotes regional foetal cardiomyocyte proliferation and adult cardiomyocyte cell-cycle re-entry.
    Cardiovasc Res, 2014. 104(3): p. 432-42. PubMed abstract
  30. Rana, M.S., M. Theveniau-Ruissy, C. De Bono, K. Mesbah, A. Francou, M. Rammah, J.N. Dominguez, M. Roux, B. Laforest, R.H. Anderson, T. Mohun, S. Zaffran, V.M. Christoffels, and R.G. Kelly
    Tbx1 coordinates addition of posterior second heart field progenitor cells to the arterial and venous poles of the heart.
    Circ Res, 2014. 115(9): p. 790-9. PubMed abstract
  31. Geyer, S.H., M.M. Nohammer, M. Matha, L. Reissig, I.E. Tinhofer, and W.J. Weninger
    High-resolution episcopic microscopy (HREM): a tool for visualizing skin biopsies.
    Microsc Microanal, 2014. 20(5): p. 1356-64. PubMed abstract
  32. Captur, G., L.R. Lopes, V. Patel, C. Li, P. Bassett, P. Syrris, D.M. Sado, V. Maestrini, T.J. Mohun, W.J. McKenna, V. Muthurangu, P.M. Elliott, and J.C. Moon
    Abnormal cardiac formation in hypertrophic cardiomyopathy: fractal analysis of trabeculae and preclinical gene expression.
    Circ Cardiovasc Genet, 2014. 7(3): p. 241-8. PubMed abstract
  33. Anderson, R.H., D.E. Spicer, N.A. Brown and T.J. Mohun
    The development of septation in the four-chambered heart.
    Anat Rec (Hoboken), 2014. 297(8): p. 1414-29. PubMed abstract
  34. Vettukattil, J.J., Z. Ahmed, A.P. Salmon, T. Mohun and R.H. Anderson
    Defects in the oval fossa: morphologic variations and impact on transcatheter closure.
    J Am Soc Echocardiogr, 2013. 26(2): p. 192-9. PubMed abstract
  35. Norris, F.C., M.D. Wong, N.D. Greene, P.J. Scambler, T. Weaver, W.J. Weninger, T.J. Mohun, R.M. Henkelman, and M.F. Lythgoe
    A coming of age: advanced imaging technologies for characterising the developing mouse.
    Trends Genet, 2013. 29(12): p. 700-11. PubMed abstract
  36. Maurer, B., S.H. Geyer and W.J. Weninger
    A chick embryo with a yet unclassified type of cephalothoracopagus malformation and a hypothesis for explaining its genesis.
    Anat Histol Embryol, 2013. 42(3): p. 191-200. PubMed abstract
  37. Captur, G., V. Muthurangu, C. Cook, A.S. Flett, R. Wilson, A. Barison, D.M. Sado, S. Anderson, W.J. McKenna, T.J. Mohun, P.M. Elliott, and J.C. Moon
    Quantification of left ventricular trabeculae using fractal analysis.
    J Cardiovasc Magn Reson, 2013. 15: p. PubMed abstract
  38. Breckenridge, R.A., I. Piotrowska, K.E. Ng, T.J. Ragan, J.A. West, S. Kotecha, N. Towers, M. Bennett, P.C. Kienesberger, R.T. Smolenski, H.K. Siddall, J.L. Offer, M.M. Mocanu, D.M. Yelon, J.R. Dyck, J.L. Griffin, A.Y. Abramov, A.P. Gould, and T.J. Mohun
    Hypoxic regulation of hand1 controls the fetal-neonatal switch in cardiac metabolism.
    PLoS Biol, 2013. 11(9): p. e1001666. PubMed abstract
  39. Bamforth, S.D., B. Chaudhry, M. Bennett, R. Wilson, T.J. Mohun, L.H. Van Mierop, D.J. Henderson, and R.H. Anderson
    Clarification of the identity of the mammalian fifth pharyngeal arch artery.
    Clin Anat, 2013. 26(2): p. 173-82. PubMed abstract
  40. Anderson, R.H., D.E. Spicer, J.M. Giroud and T.J. Mohun
    Tetralogy of Fallot: nosological, morphological, and morphogenetic considerations.
    Cardiol Young, 2013. 23(6): p. 858-66. PubMed abstract
  41. Anderson, R.H., N.A. Brown, T.J. Mohun and A.F. Moorman
    Insights from cardiac development relevant to congenital defects and adult clinical anatomy.
    J Cardiovasc Transl Res, 2013. 6(2): p. 107-17. PubMed abstract
  42. Sizarov, A., W.H. Lamers, T.J. Mohun, N.A. Brown, R.H. Anderson, and A.F. Moorman
    Three-dimensional and molecular analysis of the arterial pole of the developing human heart.
    J Anat, 2012. 220(4): p. 336-49. PubMed abstract
  43. Mohun, T.J. and W.J. Weninger
    Episcopic three-dimensional imaging of embryos.
    Cold Spring Harb Protoc, 2012. 2012(6): p. 641-6. PubMed abstract
  44. Mohun, T.J. and W.J. Weninger
    Embedding embryos for episcopic fluorescence image capturing (EFIC).
    Cold Spring Harb Protoc, 2012. 2012(6): p. 675-7. PubMed abstract
  45. Mohun, T.J. and W.J. Weninger
    Embedding embryos for high-resolution episcopic microscopy (HREM).
    Cold Spring Harb Protoc, 2012. 2012(6): p. 678-80. PubMed abstract
  46. Mohun, T.J. and W.J. Weninger
    Generation of volume data by episcopic three- dimensional imaging of embryos.
    Cold Spring Harb Protoc, 2012. 2012(6): p. 681-2. PubMed abstract
  47. Lescroart, F., T. Mohun, S.M. Meilhac, M. Bennett and M. Buckingham
    Lineage tree for the venous pole of the heart: clonal analysis clarifies controversial genealogy based on genetic tracing.
    Circ Res, 2012. 111(10): p. 1313-22. PubMed abstract
  48. Gindes, L., H. Matsui, R. Achiron, T. Mohun, S.Y. Ho, and H. Gardiner,
    Comparison of ex-vivo high-resolution episcopic microscopy with in-vivo four-dimensional high- resolution transvaginal sonography of the first-trimester fetal heart.
    Ultrasound Obstet Gynecol, 2012. 39(2): p. 196-202. PubMed abstract
  49. Anderson, R.H., B. Chaudhry, T.J. Mohun, S.D. Bamforth, D. Hoyland, H.M. Phillips, S. Webb, A.F. Moorman, N.A. Brown, and D.J. Henderson
    Normal and abnormal development of the intrapericardial arterial trunks in humans and mice.
    Cardiovasc Res, 2012. 95(1): p. 108-15. PubMed abstract
  50. Mohun, T.J. and W.J. Weninger
    Imaging heart development using high-resolution episcopic microscopy.
    Curr Opin Genet Dev, 2011. 21(5): p. 573-8. PubMed abstract
  51. de Boer, B.A., A.T. Soufan, J. Hagoort, T.J. Mohun, M.J. van den Hoff, A. Hasman, F.P. Voorbraak, A.F. Moorman, and J.M. Ruijter
    The interactive presentation of 3D information obtained from reconstructed datasets and 3D placement of single histological sections with the 3D portable document format.
    Development, 2011. 138(1): p. 159-67. PubMed abstract
  52. Anderson, R.H., T.J. Mohun and A.F. Moorman
    What is a ventricle?
    Cardiol Young, 2011. 21 Suppl 2: p. 14-22. PubMed abstract
  53. Matsui, H., T. Mohun and H.M. Gardiner
    Three-dimensional reconstruction imaging of the human foetal heart in the first trimester.
    Eur Heart J, 2010. 31(4): p. 415. PubMed abstract
  54. Dunlevy, L., M. Bennett, A. Slender, E. Lana-Elola, V.L. Tybulewicz, E.M. Fisher, and T. Mohun
    Down's syndrome-like cardiac developmental defects in embryos of the transchromosomic Tc1 mouse.
    Cardiovasc Res, 2010. 88(2): p. 287-95. PubMed abstract
  55. Anderson, R.H., A. Cook, N.A. Brown, D.J. Henderson, B. Chaudhry, and T. Mohun
    Development of the outflow tracts with reference to aortopulmonary windows and aortoventricular tunnels.
    Cardiol Young, 2010. 20 Suppl 3: p. 92-9. PubMed abstract
  56. Geyer, S.H., T.J. Mohun and W.J. Weninger
    Visualizing vertebrate embryos with episcopic 3D imaging techniques.
    Scientific World Journal, 2009. 9: p. 1423-37. PubMed abstract
  57. Weninger, W.J. and T.J. Mohun
    Three-dimensional analysis of molecular signals with episcopic imaging techniques.
    Methods Mol Biol, 2007. 411: p. 35-46. PubMed abstract
  58. Weninger, W.J., S.H. Geyer, T.J. Mohun, D. Rasskin-Gutman, T. Matsui, I. Ribeiro, F. Costa Lda, J.C. Izpisua-Belmonte, and G.B. Muller
    High-resolution episcopic microscopy: a rapid technique for high detailed 3D analysis of gene activity in the context of tissue architecture and morphology.
    Anat Embryol (Berl), 2006. 211(3): p. 213-21. PubMed abstract
  59. Going, J.J. and T.J. Mohun
    Human breast duct anatomy, the 'sick lobe' hypothesis and intraductal approaches to breast cancer.
    Breast Cancer Res Treat, 2006. 97(3): p. 285-91. PubMed abstract

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