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Patient: 52 year old male |
History: 52 year-old man with metastatic colorectal cancer.
CT
Figure 1
Impression?
What therapy can be offered to this patient?
Figure 2 Figure 3 Figure 4
How and why do we perform this study? Interpretation?
Three Weeks later
The patient was treated with Y-90 microspheres to the right hepatic lobe.
Immediately after Y-90 microsphere treatment another MAA injection was performed into the replaced left hepatic artery to evaluate previously described esophagogastric junction tracer activity, attributed to reflux into the left gastric artery.
Figure 5 Figure 6 Figure 7 Figure 8 Figure 9
Interpretation?
What artifact is present and what is its cause?
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Image Size:[small][as-submitted]
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Findings: Hepatic Perfusion Scinitigraphy (Initial Study prior to therapy)
RADIOPHARMACEUTICAL: 5.3 mCi Tc-99m MAA i.a.
1. Following intra-arterial infusion of Tc-99m MAA particles into the catheterized hepatic artery, there is heterogeneous perfusion of the right and left hepatic lobes. There is relatively higher tracer deposition in the left hepatic lobe.
2. Intense tracer deposition in the distal esophagus and gastroesophageal junction, indicating extrahepatic perfusion of these structures during Tc-99m MAA injection, likely related to the left replaced hepatic artery injection, with reflux into the left gastric artery.
3. No significant pulmonary activity. The relative lung perfusion is 7% of the injected dose.
Angiographic Y-90 Microsphere Treatment (3 weeks after the initial study)
1. Successful Sirtex radioembolization of the right hepatic artery.
2. Successful repeated injection of MAA to the replace left hepatic artery (to clarify if the previous tracer activity at the level of the gastroesophageal junction was due to reflux to the left gastric artery).
Hepatic Perfusion Scinitigraphy (3 weeks after the initial study)
RADIOPHARMACEUTICAL: 2.4 mCi Tc-99m MAA i.a.
1. Following intra-arterial infusion of Tc-99m MAA particles into the catheterized left hepatic artery, there is patchy heterogenous perfusion of the left hepatic lobe.
2. There is significant scatter radiation, thus not allowing the calculation of relative lung perfusion.
3. No discrete tracer deposition was identified in the distal esophagus and gastroesophageal junction on this exam to suggest perfusion of this region via the hepatic artery injection. |
DDx: Bremsstahlung radiation from concurrent Y-90 administration
Other possible artifacts that might give a similar appearance:
FDG PET patient (unshielded) adjacent to the imaging room
Other recent higher energy imaging study
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Diagnosis: Significant scatter radiation secondary to bremsstrahlung radiation originating from Y-90 microspheres injection performed just prior a Tc99m MAA injection and imaging. |
References: Murthy et al. "Yttrium-90 Microsphere Therapy for Hepatic Malignancy: Devices, Indications, Technical Considerations, and Potential Complications" 2005. Radiographics; 25: S41-S55. |
Comments: No comments posted. |
Additional Details:
Case Number: 245511Owner(s): Andrew Homb and Jerold Wallis, Assoc Prof of RadiologyLast Updated: 02-07-2013 The reader is fully responsible for confirming the accuracy of this content. |