SPEM: a state-of-the-art instrument for high resolution molecular imaging of small animal organs.
OBJECTIVE
To describe the Single Photon Emission Microscope (SPEM), a state-of-the-art instrument for small animal SPECT imaging, and characterize its performance presenting typical images of different animal organs.


METHODS
SPEM consists of two independent imaging devices based on high resolution scintillators, high sensitivity and resolution Electron-Multiplying CCDs and multi-pinhole collimators. During image acquisition, the mouse is placed in a rotational vertical holder between the imaging devices. Subsequently, an appropriate software tool based on the Maximum Likelihood algorithm iteratively produces the volumetric image. Radiopharmaceuticals for imaging kidneys, heart, thyroid and brain were used. The mice were injected with 74 to 148 MBq/0,3mL and scanned for 40 to 80 minutes, 30 to 60 minutes afterwards. During this procedure, the animals remained under ketamine/xilazine anesthesia.


RESULTS
SPEM images of different mouse organs are presented, attesting the imaging capabilities of the instrument.


CONCLUSIONS
SPEM is an innovative technology for small animal SPECT imaging providing high resolution images with appropriate sensitivity for pre-clinical research. Its use with appropriate radiotracers will allow translational investigation of several animal models of human diseases, their pharmacological treatment and the development of potential new therapeutic agents.
Instituto do Cérebro, Hospital Israelita Albert Einstein.
Marilia Alves dos
MA
Reis
Jorge
J
Mejia
Ilza Rosa
IR
Batista
Marycel Rosa Felisa Figols de
MR
Barboza
Solange Amorim
SA
Nogueira
Jairo
J
Wagner
Francisco Romero
FR
Cabral
Petrick Marcellus Victorio Mendonça
PM
Davoglio
Vanessa Costhek
VC
Abílio
Geng
G
Fu
Nan
N
Li
Ling Jian
LJ
Meng
Ming Chi
MC
Shih
Chin-Tu
CT
Chen
Edson
E
Amaro Junior
Rodrigo Affonseca
RA
Bressan
D000818:Animals; D001921:Brain / Q000000981:diagnostic imaging*; D004867:Equipment Design; D006321:Heart / Q000000981:diagnostic imaging*; D007668:Kidney / Q000000981:diagnostic imaging*; D008297:Male; D051379:Mice; D013961:Thyroid Gland / Q000000981:diagnostic imaging*; D015899:Tomography, Emission-Computed, Single-Photon / Q000295:instrumentation*