Limits...
Theranostic Imaging of Yttrium-90.

Wright CL, Zhang J, Tweedle MF, Knopp MV, Hall NC - Biomed Res Int (2015)

Bottom Line: This paper overviews Yttrium-90 ((90)Y) as a theranostic and nuclear medicine imaging of (90)Y radioactivity with bremsstrahlung imaging and positron emission tomography.In addition, detection and optical imaging of (90)Y radioactivity using Cerenkov luminescence will also be reviewed.Methods and approaches for qualitative and quantitative (90)Y imaging will be briefly discussed.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiology, The Ohio State University Wexner Medical Center, Columbus, OH 43210, USA.

ABSTRACT
This paper overviews Yttrium-90 ((90)Y) as a theranostic and nuclear medicine imaging of (90)Y radioactivity with bremsstrahlung imaging and positron emission tomography. In addition, detection and optical imaging of (90)Y radioactivity using Cerenkov luminescence will also be reviewed. Methods and approaches for qualitative and quantitative (90)Y imaging will be briefly discussed. Although challenges remain for (90)Y imaging, continued clinical demand for predictive imaging response assessment and target/nontarget dosimetry will drive research and technical innovation to provide greater clinical utility of (90)Y as a theranostic agent.

No MeSH data available.


Related in: MedlinePlus

Yttrium-90 as a theranostic agent (i.e., it demonstrates both therapeutic and diagnostic attributes). Yttrium-90 (90Y, center) is a high-energy β− emitting radioisotope used clinically for targeted radiotherapy (upper left). The targeted radiotherapy applications include direct injection of 90Y into a body space or cavity, conjugation of 90Y to a peptide for peptide receptor radionuclide therapy (PRRT), or an antibody for radioimmunotherapy (RIT), or incorporation of 90Y into a resin or glass microsphere for radioembolization (RE) therapy. The high-energy β− particle emission produces a continuous spectrum bremsstrahlung radiation which can then be imaged using conventional nuclear medicine imaging systems such as planar gamma cameras, SPECT, and SPECT/CT (lower left). Although the vast majority of 90Y decays are β− emitting, 32 per million 90Y decays result in internal pair production that can be readily imaged using conventional PET/CT and PET/MRI systems (lower right). The high-energy β− particle emission also produces continuous spectrum light photons or Cerenkov luminescence which can then be imaged using existing bioluminescence imaging systems (upper right). These 3 noninvasive imaging approaches allow for simultaneous diagnostic assessment/localization of the therapeutic 90Y radioactivity.
© Copyright Policy - open-access
Related In: Results  -  Collection


getmorefigures.php?uid=PMC4464848&req=5

fig1: Yttrium-90 as a theranostic agent (i.e., it demonstrates both therapeutic and diagnostic attributes). Yttrium-90 (90Y, center) is a high-energy β− emitting radioisotope used clinically for targeted radiotherapy (upper left). The targeted radiotherapy applications include direct injection of 90Y into a body space or cavity, conjugation of 90Y to a peptide for peptide receptor radionuclide therapy (PRRT), or an antibody for radioimmunotherapy (RIT), or incorporation of 90Y into a resin or glass microsphere for radioembolization (RE) therapy. The high-energy β− particle emission produces a continuous spectrum bremsstrahlung radiation which can then be imaged using conventional nuclear medicine imaging systems such as planar gamma cameras, SPECT, and SPECT/CT (lower left). Although the vast majority of 90Y decays are β− emitting, 32 per million 90Y decays result in internal pair production that can be readily imaged using conventional PET/CT and PET/MRI systems (lower right). The high-energy β− particle emission also produces continuous spectrum light photons or Cerenkov luminescence which can then be imaged using existing bioluminescence imaging systems (upper right). These 3 noninvasive imaging approaches allow for simultaneous diagnostic assessment/localization of the therapeutic 90Y radioactivity.

Mentions: Other therapeutic β− emitting radioisotopes (e.g., 131I for thyroid cancer [15] and Samarium-153 (153Sm) for osseous metastases [16]) also produce discrete gamma photons which can be imaged after therapy but contribute to additional absorbed radiation dose. One advantage of 90Y is that it is an almost pure β− emitting radioisotope which lacks such gamma photons [6]. On the other hand, because of the lack of gamma photons from 90Y, conventional scintigraphic imaging and assessment of the posttherapy distribution of its radioactivity are challenging. This lack of gamma photons led to the development and use of surrogate gamma-emitting radioisotopes (e.g., Indium-111- (111In-) labeled peptides and antibodies) with analogous chemical properties as a tracer for 90Y dosimetric assessment and pharmacokinetics [2, 17]. Likewise, Technetium-99m- (99mTc-) labeled macroaggregated albumin (MAA) is currently used as a surrogate radiotracer for planning 90Y microsphere RE therapy [18–20]. It is important to note that use of such surrogate tracers may not always accurately predict 90Y radiotherapy effects in vivo and such discrepancies may result in unanticipated and unintended toxicities [17, 21–23]. Given that surrogate tracer agents may not always predict the precise posttherapeutic distribution of 90Y, subsequent imaging assessment of 90Y radioactivity is an important adjunctive step to assess and verify delivery and dosimetric distribution of the 90Y agent to the target(s) and exclude any nontargeted delivery [24]. Likewise, accurate quantification of 90Y radioactivity in both targeted lesions and nontargeted tissues would allow for improved comparisons of radiotherapy outcomes in patients. This review will subsequently discuss the different diagnostic imaging approaches used for therapeutic 90Y radioactivity assessment (Figure 1).


Theranostic Imaging of Yttrium-90.

Wright CL, Zhang J, Tweedle MF, Knopp MV, Hall NC - Biomed Res Int (2015)

Yttrium-90 as a theranostic agent (i.e., it demonstrates both therapeutic and diagnostic attributes). Yttrium-90 (90Y, center) is a high-energy β− emitting radioisotope used clinically for targeted radiotherapy (upper left). The targeted radiotherapy applications include direct injection of 90Y into a body space or cavity, conjugation of 90Y to a peptide for peptide receptor radionuclide therapy (PRRT), or an antibody for radioimmunotherapy (RIT), or incorporation of 90Y into a resin or glass microsphere for radioembolization (RE) therapy. The high-energy β− particle emission produces a continuous spectrum bremsstrahlung radiation which can then be imaged using conventional nuclear medicine imaging systems such as planar gamma cameras, SPECT, and SPECT/CT (lower left). Although the vast majority of 90Y decays are β− emitting, 32 per million 90Y decays result in internal pair production that can be readily imaged using conventional PET/CT and PET/MRI systems (lower right). The high-energy β− particle emission also produces continuous spectrum light photons or Cerenkov luminescence which can then be imaged using existing bioluminescence imaging systems (upper right). These 3 noninvasive imaging approaches allow for simultaneous diagnostic assessment/localization of the therapeutic 90Y radioactivity.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4464848&req=5

fig1: Yttrium-90 as a theranostic agent (i.e., it demonstrates both therapeutic and diagnostic attributes). Yttrium-90 (90Y, center) is a high-energy β− emitting radioisotope used clinically for targeted radiotherapy (upper left). The targeted radiotherapy applications include direct injection of 90Y into a body space or cavity, conjugation of 90Y to a peptide for peptide receptor radionuclide therapy (PRRT), or an antibody for radioimmunotherapy (RIT), or incorporation of 90Y into a resin or glass microsphere for radioembolization (RE) therapy. The high-energy β− particle emission produces a continuous spectrum bremsstrahlung radiation which can then be imaged using conventional nuclear medicine imaging systems such as planar gamma cameras, SPECT, and SPECT/CT (lower left). Although the vast majority of 90Y decays are β− emitting, 32 per million 90Y decays result in internal pair production that can be readily imaged using conventional PET/CT and PET/MRI systems (lower right). The high-energy β− particle emission also produces continuous spectrum light photons or Cerenkov luminescence which can then be imaged using existing bioluminescence imaging systems (upper right). These 3 noninvasive imaging approaches allow for simultaneous diagnostic assessment/localization of the therapeutic 90Y radioactivity.
Mentions: Other therapeutic β− emitting radioisotopes (e.g., 131I for thyroid cancer [15] and Samarium-153 (153Sm) for osseous metastases [16]) also produce discrete gamma photons which can be imaged after therapy but contribute to additional absorbed radiation dose. One advantage of 90Y is that it is an almost pure β− emitting radioisotope which lacks such gamma photons [6]. On the other hand, because of the lack of gamma photons from 90Y, conventional scintigraphic imaging and assessment of the posttherapy distribution of its radioactivity are challenging. This lack of gamma photons led to the development and use of surrogate gamma-emitting radioisotopes (e.g., Indium-111- (111In-) labeled peptides and antibodies) with analogous chemical properties as a tracer for 90Y dosimetric assessment and pharmacokinetics [2, 17]. Likewise, Technetium-99m- (99mTc-) labeled macroaggregated albumin (MAA) is currently used as a surrogate radiotracer for planning 90Y microsphere RE therapy [18–20]. It is important to note that use of such surrogate tracers may not always accurately predict 90Y radiotherapy effects in vivo and such discrepancies may result in unanticipated and unintended toxicities [17, 21–23]. Given that surrogate tracer agents may not always predict the precise posttherapeutic distribution of 90Y, subsequent imaging assessment of 90Y radioactivity is an important adjunctive step to assess and verify delivery and dosimetric distribution of the 90Y agent to the target(s) and exclude any nontargeted delivery [24]. Likewise, accurate quantification of 90Y radioactivity in both targeted lesions and nontargeted tissues would allow for improved comparisons of radiotherapy outcomes in patients. This review will subsequently discuss the different diagnostic imaging approaches used for therapeutic 90Y radioactivity assessment (Figure 1).

Bottom Line: This paper overviews Yttrium-90 ((90)Y) as a theranostic and nuclear medicine imaging of (90)Y radioactivity with bremsstrahlung imaging and positron emission tomography.In addition, detection and optical imaging of (90)Y radioactivity using Cerenkov luminescence will also be reviewed.Methods and approaches for qualitative and quantitative (90)Y imaging will be briefly discussed.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiology, The Ohio State University Wexner Medical Center, Columbus, OH 43210, USA.

ABSTRACT
This paper overviews Yttrium-90 ((90)Y) as a theranostic and nuclear medicine imaging of (90)Y radioactivity with bremsstrahlung imaging and positron emission tomography. In addition, detection and optical imaging of (90)Y radioactivity using Cerenkov luminescence will also be reviewed. Methods and approaches for qualitative and quantitative (90)Y imaging will be briefly discussed. Although challenges remain for (90)Y imaging, continued clinical demand for predictive imaging response assessment and target/nontarget dosimetry will drive research and technical innovation to provide greater clinical utility of (90)Y as a theranostic agent.

No MeSH data available.


Related in: MedlinePlus