Phantom validation of quantitative Y-90 PET/CT-based dosimetry in liver radioembolization.

Background: PET/CT has recently been shown to be a viable alternative to traditional post-infusion imaging methods providing good quality images of Y-laden microspheres after selective internal radiation therapy (SIRT). In the present paper, first we assessed the quantitative accuracy of Y-PET using an anthropomorphic phantom provided with lungs, liver, spine, and a cylindrical homemade lesion located into the hepatic compartment. Then, we explored the accuracy of different computational approaches on dose calculation, including (I) direct Monte Carlo radiation transport using Raydose, (II) Kernel convolution using Philips Stratos, (III) local deposition algorithm, (IV) Monte Carlo technique (MCNP) considering a uniform activity distribution, and (V) MIRD (Medical Internal Radiation Dose) analytical approach.

Absorbed dose to lesion and clinical outcome after liver radioembolization with 90Y microspheres: a case report of PET-based dosimetry.

A 54-year-old woman with metastatic colorectal carcinoma underwent liver radioembolization with (90)Y resin microspheres. Microsphere biodistribution was assessed 2 h after the treatment through a 20-min long (90)Y PET scan. Isodose map and lesion dose-volume histogram (DVH) were then evaluated using a MATLAB-based code.

90Y PET-based dosimetry after selective internal radiotherapy treatments.

Objectives: The decay of 90Y has a minor branch to the O+ first excited state of 89Zr, the de-excitation of which to the fundamental state is followed by a β+–β- emission that has been used recently for biodistribution assessment after selective internal radiotherapy (SIRT) treatments. The purpose of the present study is to demonstrate the feasibility of 90Y PET imaging for dose assessment after radioembolization with 90Y microspheres.

Methods: Activity quantification was validated through preliminary phantom studies using a cylindrical body phantom composed of six inserts of different volumes filled with a calibrated amount of 90Y microspheres.

90Y-PET for the assessment of microsphere biodistribution after selective internal radiotherapy.

Objectives: To demonstrate the feasibility of 90Y-PET imaging for biodistribution assessment after selective internal radiotherapy treatments with 90Y-microspheres, comparing the results with 99mTc-macroaggregated albumin (MAA) images obtained with single-photon emission computed tomography.

Methods: Preliminary studies were performed with the aim of evaluating the imaging system spatial resolution and scanner sensitivity for detecting annihilation photons. Subsequently, microsphere distribution was evaluated in 10 patients who underwent liver selective internal radiotherapy treatment.

The role of 99mTc-tetrofosmin Pinhole-SPECT in breast cancer axillary lymph node staging.

The number of metastatic axillary nodes represents one of the most important prognostic factors in preoperative breast cancer patients. 99mTc-Tetrofosmin high resolution Pinhole (P)-SPECT was employed in 112 patients, 100 with breast cancer and 12 with benign mammary lesions, to ascertain axillary lymph node involvement. Axillary P-SPECT images were acquired utilizing specific software connected to a circular high resolution, single-head gamma camera equipped with a pinhole collimator with aperture size of 4.