Micro-CT myelography using contrast-enhanced digital subtraction: feasibility and initial results in healthy rats
- 33 Downloads
The spinal subarachnoid space (SSAS) is vital for neural performance. Although models of spinal diseases and trauma are used frequently, no methods exist to obtain high-resolution myelograms in rodents. Thereby, our aim was to explore the feasibility of obtaining high-resolution micro-CT myelograms of rats by contrast-enhanced dual-energy (DE) and single-energy (SE) digital subtraction.
Micro-CT contrast-enhanced DE and SE imaging protocols were implemented with live adult rats (total of 18 animals). For each protocol, contrast agents based on iodine (Iomeron® 400 and Fenestra® VC) and gold nanoparticles (AuroVist™ 15 nm) were tested. For DE, images at low- and high-energy settings were acquired after contrast injection; for SE, one image was acquired before and the other after contrast injection. Post-processing consisted of region of interest selection, image registration, weighted subtraction, and longitudinal alignment.
High-resolution myelograms were obtained with contrast-enhanced digital subtraction protocols. After qualitative and quantitative (contrast-to-noise ratio) analyses, we found that the SE acquisition protocol with Iomeron® 400 provides the best images. 3D contour renderings allowed visualization of SSAS and identification of some anatomical structures within it.
This in vivo study shows the potential of SE contrast-enhanced myelography for imaging SSAS in rat. This approach yields high-resolution 3D images without interference from adjacent anatomical structures, providing an innovative tool for further assessment of studies involving rat SSAS.
KeywordsMetal nanoparticles Myelography Subarachnoid space Subtraction technique Three-dimensional X-ray microtomography
Compliance with ethical standards
This study was funded by the Fund for Health Research (Grant FIS/IMSS/PROT/G15/1465) from the Instituto Mexicano del Seguro Social (http://www.imss.gob.mx) and institutional research resources from the National Cancer Institute, Mexico (http://www.incan.salud.gob.mx).
Conflict of interest
The authors declare that they have no conflict of interest.
This study was approved by the Committee of Ethics in Research of the Instituto Mexicano del Seguro Social (File no. R-2014-785-099). All applicable international, national, and/or institutional guidelines for the care and use of animals were followed.
This article does not contain any studies with human participants performed by any of the authors.
- 5.Brodbelt AR, Stoodley MA, Watling AM, Tu J, Burke S, Jones NR (2003) Altered subarachnoid space compliance and fluid flow in an animal model of posttraumatic syringomyelia. Spine (Phila Pa 1976) 28:E413–E4199. https://doi.org/10.1097/01.BRS.0000092346.83686.B9 CrossRefGoogle Scholar
- 7.Reyes-Alva HJ, Franco-Bourland RE, Martinez-Cruz A, Grijalva I, Madrazo I, Guizar-Sahagun G (2013) Spatial and temporal morphological changes in the subarachnoid space after graded spinal cord contusion in the rat. J Neurotrauma 30:1084–1091. https://doi.org/10.1089/neu.2012.2764 CrossRefGoogle Scholar
- 9.Mason WP, Yeh SD, DeAngelis LM (1998) 111Indium-diethylenetriamine pentaacetic acid cerebrospinal fluid flow studies predict distribution of intrathecally administered chemotherapy and outcome in patients with leptomeningeal metastases. Neurology 50:438–444. https://doi.org/10.1212/WNL.50.2.438 CrossRefGoogle Scholar
- 13.Levy LM (1999) MR imaging of cerebrospinal fluid flow and spinal cord motion in neurologic disorders of the spine. Magn Reson Imaging Clin N Am 7:573–587Google Scholar
- 14.Mauer UM, Freude G, Danz B, Kunz U (2008) Cardiac-gated phase-contrast magnetic resonance imaging of cerebrospinal fluid flow in the diagnosis of idiopathic syringomyelia. Neurosurgery 63:1139–1944. https://doi.org/10.1227/01.NEU.0000334411.93870.45 CrossRefGoogle Scholar
- 15.Yiallourou TI, Kroger JR, Stergiopulos N, Maintz D, Martin BA, Bunck AC (2012) Comparison of 4D phase-contrast MRI flow measurements to computational fluid dynamics simulations of cerebrospinal fluid motion in the cervical spine. PLoS One 7:e52284. https://doi.org/10.1371/journal.pone.0052284 CrossRefGoogle Scholar
- 18.Castillo JP, Corona-Nieblas L, Berumen F, Ayala-Domínguez L, Medina LA, Brandan ME (2016) Optimization of dual-energy subtraction for preclinical studies using a commercial MicroCT unit. AIP Conf Proc. https://doi.org/10.1063/1.4954125
- 20.Cruz-Bastida JP, Rosado-Mendez I, Perez-Ponce H, Villaseñor Y, Galván HA, Trujillo FE, Benítez L, Brandan ME (2012) Contrast optimization in clinical contrast-enhanced digital mammography images. In: Maidment ADA, Bakic PR, Gavenonis S (eds) Breast imaging, vol 7361. Springer, Berlin, Heidelberg, pp 17–23CrossRefGoogle Scholar
- 27.Ahrens J, Geveci B, Law C (2005) ParaView: an end-user tool for large data visualization. In: Hansen CD, Johnson CR (eds) The Visualization Handbook. Elsevier, Oxford, pp 717–731Google Scholar
- 30.Ritman EL (2004) Micro-computed tomography: current status and developments. Annu Rev Biomed Eng 6:185–208. https://doi.org/10.1146/annurev.bioeng.6.040803.140130 CrossRefGoogle Scholar
- 32.Choukèr A, Lizak M, Schimel D, Helmberger T, Ward JM, Despres D, Kaufmann I, Bruns C, Löhe F, Ohta A, Sitkovsky MV, Klaunberg B, Thiel M (2008) Comparison of fenestra VC contrast-enhanced computed tomography imaging with gadopentetate dimeglumine and ferucarbotran magnetic resonance imaging for the in vivo evaluation of murine liver damage after ischemia and reperfusion. Investig Radiol 43:77–91. https://doi.org/10.1097/RLI.0b013e318155aa2e CrossRefGoogle Scholar
- 33.Hubbell JH, Seltzer SM (2004) X-ray mass attenuation coefficients (NIST standard reference database 126). National Institute of Standards and Technology. https://doi.org/10.18434/T4D01F