Tumor T2 Star
Tumor T2 Star - Related Videos
05:30
Measurement of Tumor T2* Relaxation Times after Iron Oxide Nanoparticle Administration
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Cited by 1 •
2023
We present a standardized protocol for the quantification of T2* relaxation times of tumors using external software. Multi-echo gradient echo images are acquired and fed into the software to create tumor T2* maps and measure tumor T2* relaxation times.
04:11
DCE-MRI of Orthotopic Pancreatic Tumor Xenografts: A Method to Assess Microvasculature in a Target Tumor Tissue
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2023
This video describes the technique of DCE-MRI for orthotropic pancreatic tumor xenografts in mice. DCE-MRI is a non-invasive method to analyze microvasculature in a target tissue, and useful to assess vascular response in a tumor following a novel therapy. This method will assist investigators to apply DCE-MRI for orthotopic gastrointestinal cancer mouse models.
06:56
Particles without a Box: Brush-first Synthesis of Photodegradable PEG Star Polymers under Ambient Conditions
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Cited by 17 •
2013
Poly(ethylene glycol) (PEG) brush-arm star polymers (BASPs) with narrow mass distributions and tunable nanoscopic sizes are synthesized in via ring opening metathesis polymerization (ROMP) of a PEG-norbornene macromonomer followed by transfer of portions of the resulting living brush initiator to vials containing varied amounts of a rigid, photo-cleavable bis-norbornene crosslinker.
05:48
Tissue Engineering of Tumor Stromal Microenvironment with Application to Cancer Cell Invasion
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Cited by 7 •
2014
Tissue engineered fibroblast-derived native matrix is an emerging tool to generate a stromal substrate which supports epithelial cell proliferation and differentiation. Here a protocol applying this methodology to assess the impact of different stromal cell types on tumor cell biology is presented.
12:03
In Vivo Model for Testing Effect of Hypoxia on Tumor Metastasis
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Cited by 6 •
2016
This manuscript describes the development of an animal model that allows for the direct testing of the effects of tumor hypoxia on metastasis and the deciphering the mechanisms of its action. Although the experiments described here focus on Ewing sarcoma, a similar approach can be applied to other tumor types.
FAQs
Unlike a measure based only on intrinsic spin-spin relaxation, T2* is also sensitive to local magnetic-field variations. Gradient-echo signal therefore falls because microscopic susceptibility differences add to transverse dephasing. This makes the value responsive to sources such as deoxygenated blood, hemorrhage, iron, and calcification, but also means it represents combined tissue and susceptibility effects rather than a single property.
These substances act as susceptibility sources that disturb the local magnetic field. The resulting field variations accelerate loss of transverse magnetization during gradient-echo imaging, altering the measured T2* value. Consequently, regions containing hemorrhage, iron, calcification, or deoxygenated blood may contribute to signal behavior that reveals tissue features not readily apparent on conventional anatomical MRI.
Spatial differences in T2* can reflect variation in vascularity, oxygenation, blood products, iron, or calcification within a tumor. Such variation may indicate that the lesion is not uniform, even when its anatomical appearance seems relatively consistent. Mapping these differences therefore adds a susceptibility-sensitive view of tumor composition and supports more detailed characterization.
Gradient-echo imaging is sensitive to signal loss produced by both intrinsic transverse relaxation and magnetic-field variations. That sensitivity allows T2* mapping to capture susceptibility effects associated with tumor blood, oxygenation, hemorrhage, iron, or calcification. The resulting measurements complement conventional anatomical images by emphasizing relaxation behavior and local field differences rather than structure alone.
T2* mapping can support assessment of tumor vascularity, oxygenation, blood products, and tissue heterogeneity. These characteristics provide complementary information to conventional anatomical MRI, which may not display all of the underlying tissue differences. In practice and research, the measurement contributes to a broader picture of tumor composition when interpreted alongside other imaging findings.
Serial T2* measurements may provide information about treatment-related effects by showing how susceptibility-sensitive tissue behavior changes over time. Such changes can be considered alongside anatomical imaging and other MRI biomarkers rather than interpreted in isolation. This longitudinal use supports research into therapy response and may help identify imaging changes associated with evolving tumor tissue.
T2* is influenced by several overlapping factors, including spin-spin relaxation and susceptibility sources. A single value may therefore reflect multiple tissue processes rather than one definitive biological feature. Combining it with other MRI biomarkers can improve tumor characterization by integrating complementary information and can strengthen research evaluations of vascularity, oxygenation, heterogeneity, and therapy-related change.