Software-based PET-MR image coregistration: combined PET-MRI for the rest of us!

Background: With the introduction of hybrid positron emission tomography/magnetic resonance imaging (PET/MRI), a new imaging option to acquire multimodality images with complementary anatomical and functional information has become available. Compared with hybrid PET/computed tomography (CT), hybrid PET/MRI is capable of providing superior anatomical detail while removing the radiation exposure associated with CT. The early adoption of hybrid PET/MRI, however, has been limited.

Supratentorial primitive neuroectodermal tumor metastasis to the abdomen via a ventriculoperitoneal shunt.

Primitive neuroectodermal tumors (PNETs) include a heterogeneous group that originate from primitive neuroepithelial cells. PNETs are prone to cerebrospinal fluid seeding and central nervous system spread. Infratentorial PNET, or medulloblastoma, is a common brain tumor in children and metastatic spread to the abdomen via a ventriculoperitoneal (VP) shunt has been described.

Estimation of gallbladder ejection fraction utilizing cholecystokinin-stimulated magnetic resonance cholangiography and comparison with hepatobiliary scintigraphy.

Purpose: To evaluate the utility of magnetic resonance cholangiography (MRC) in estimation of gallbladder ejection fraction (GBEF) and to comparing this value to the conventional method, hepatobiliary scintigraphy (HBS).

Materials And Methods: Twenty-one healthy volunteers were imaged on sequential weeks to determine GBEF using MRC and HBS. GBEF was calculated by HBS after infusion of 20 ng/kg of sincalide following injection of 111 Mbq of Tc 99(m) mebrofenin.