[(111)In]Pentetreotide SPECT scintigraphy in neuroendocrine tumors: variability of reconstructing parameters related to patient characteristics and each body part.

Aim: Multi-headvariable-geometry gammacamera, allow us to carry out multi-dimensional scintigraphic single photon emission computed tomography (SPECT) studies, with the possibility of creating coronal, axial, sagittal, three-dimensional images like the last generation of multi-slice RMI or multislice CT scan. The aim of this paper is to weigh up the reconstruction parameters to apply in [(0111)In]Pentetreotide scintigraphy for evaluating neuroendocrine tumors and try to standardize them.
Methods: We have studied a group of 93 patients suffering from neuroendocrine tumors. Examination was carried out after administration of [111In] Pentetreotide with whole body and static acquisitions after 4 and 24 h, followed by SPECT acquisitions of head, thorax and abdomen after 24 h.
Results: The results obtained show that the Filtered Back Projection using Butterworth filter can produce images of greater resolution than the iterative reconstruction method. Moreover, the reconstruction parameters are easily standardizable for head and thorax while for the abdomen the choice of these parameters is more difficult.
Conclusions: Our data show that filtered back projection with Butterworth filter is the best procedure to carry out a SPECT examination with [111In] Pentetreotide.