Bone scintigraphy hot-spot in projection to rib and kidney: role of single photon emission computer tomography/computer tomography in distinguishing a urine collection in renal calyx from a metastasis to rib.

On planar bone scintigrams, activity enhancement foci in projection to kidney and lower ribs can arise from the kidney, or from bone lesions. A differentiation based only on the exact location and shape of the hot spot can sometimes be misleading, resulting in a false qualification of a rib metastatic lesion as urine collection in the kidney or opposite. The authors illustrate the problem with three cases: In two patients, such a hot spot appeared to be the solitary metastatic focus; in one, highly suggestive for solitary metastatic focus, it was proven to be a urine collection.

Approximation of time-uptake curve to a modified Bateman equation based on three uptake tests - potential value for dosimetry of corpuscular radiation.

Background: Many models of assessing radiopharmaceutical kinetics for dosimetry have been developed, starting from the formula of Marinelli. They are either inaccurate or require taking multiple patient uptake measurements.

Material And Methods: Radiotracer behavior is approached to a modified Bateman equation ("biphasic model").

Enhanced accumulation of bone seekers at superior lateral orbital margin: potential origin.

Enhanced accumulation of the radiotracer at superior lateral orbital margin is a common finding in bone scintigraphy. Its possible sources are discussed and illustrated with examples from own archive of the authors as well as from the literature. These sources include: Physiologically enhanced bone metabolism at frontozygomatic suture (normal variant), a metastasis at this suture (illustrated with an example of solitary metastasis from prostate cancer), lesions to the zygomatic bone or the greater wing of the sphenoid bone, deepened fossa for lacrimal gland and the gland itself.

Congenital vascular malformations in scintigraphic evaluation.

Background: Congenital vascular malformations are tumour-like, non-neoplastic lesions caused by disorders of vascular tissue morphogenesis. They are characterised by a normal cell replacement cycle throughout all growth phases and do not undergo spontaneous involution. Here we present a scintigraphic image of familial congenital vascular malformations in two sisters.