Search

National audience

Studies of the biodistribution of radiolabeled compounds in rodents frequently are performed during the process of development of new pharmaceutical drugs. This article presents the evaluation of a new whole-body animal SPECT system, called the Linoview SPECT system. METHODS: Linoview SPECT is based on the linear orbit acquisition technique associated with slit-aperture collimators mounted on 4 pixelated CsI(Na) detectors composed of an array of small, individual crystal elements. Sliding iridium rods allow variation of the collimator aperture. Hot-rod and cold-rod phantoms filled with (99m)Tc were imaged. Mice were imaged, and kidney radioactivity was measured after injection of (99m)Tc-dimercaptosuccinic acid and (111)In-diethylenetriaminepentaacetic acid-d-Phe(1)-octreotide ((111)In-pentetreotide; Octreo-Scan(111)). RESULTS: Phantom studies showed that hot rods separated by 0.35 mm can be distinguished and that 0.65-mm-diameter cold rods can be visualized, both at low-counting-rate acquisitions (111 and 59 MBq x h, respectively). In both mouse studies, the SPECT images allowed a clear delineation of the radioactivity concentrated over the cortex area of the kidneys, whereas the pelvis and the pelviureteral junction (1 mm) appeared as cold areas. The quantitative data derived from SPECT were in good agreement with the radioactivity counting obtained with a gamma-counter after isolation of the kidneys. In addition, in the mouse injected with (111)In-pentetreotide, the kidney radioactivity distribution seen with SPECT was in agreement with the ex vivo autoradiograms of the isolated kidneys. CONCLUSION: The phantom studies showed a clear improvement of the spatial resolution over the results reported in the literature with other dedicated small-animal SPECT systems, especially in cold-rod phantom studies. The increased performance can be ascribed to the high stability of the system with regard to the statistical noise present in the acquired data. The mouse studies showed that this system will be most useful for in vivo high-resolution SPECT and quantitative biodistribution studies in rodents, even with medium-energy radioisotopes that are difficult to image, such as (111)In.

The main aim of the EANM Task Group on Quality Assurance and Standardisation is to develop harmonised clinical procedures that are accepted within Europe. In order to achieve an evidence-based analysis of guidelines in the 27 EANM member societies, a survey was conducted. A questionnaire in mid 1999 investigated three major questions: (1) current status of national guidelines in EANM member societies, (2) specification of the cover and level of these national guidelines, and (3) future desires for national, EANM and SNM guidelines. The complete response rate was 96% (26/27). Guidelines are required by 19 of 27 member societies and have been initiated by 16 member societies. Guidelines are provided by 13 member societies, generally in the national language. In ten societies, specialists other than nuclear medicine physicians, mostly physicists and radiopharmacists, take the lead on some guidelines. Moreover, in some national societies there is active collaboration with other medical societies when writing guidelines, particularly cardiology societies. Currently, only 18% of the necessary procedure guidelines are covered. Compared with a survey conducted in 1993 by the EANM Committee on Quality Assurance and Standardisation, slow progress has been made in this regard, but compared with a survey conducted by the same committee in 1996 in 23 EANM member societies, the number of member societies providing guidelines has approximately doubled. Moreover, 26 of 27 member societies share a commitment for future development of guidelines and 21 of 27 prefer EANM guidelines to national guidelines. The results of this questionnaire justify the need for close co-operation between EANM, EANM member societies, the EANM Task Group on "Quality Assurance and Standardisation" and the Guideline Committee of the SNM. The clinical priorities are considered to be cardiac, renal and brain procedures