PET amyloid imaging: state of the art and technical considerations
Barra laterale dell'articolo
Contenuto principale dell'articolo
Abstract
INTRODUCTION
The development of PET radiopharmaceuticals suitable for the identification and in vivo quantification of β Amyloid plaques has been the focus of intense research, representing a useful means for the non-invasive detection of β Amyloid plaques in subjects affected by the Alzheimer's disease (AD). The purpose of this article is to provide a general overview of the application of PET radiopharmaceuticals currently available for in vivo imaging of β amyloid plaques. The aim is therefore to describe the chemical and synthetic characteristics of the main radiopharmaceuticals currently used in in vivo amyloid imaging and to provide a technical description of the acquisition protocols, always keeping the patient at the center of each step.
MATERIALS AND METHODS
Radiopharmaceuticals for PET imaging of amyloid β include two broad classes: planar hetero aromatic compounds and alkenes analogs. Among the former are 11C PiB and 18F Flutemetmol. While among the analogues of alkenes, the most used are the following two radiolabelled compounds: [18F] Florbetaben; [18F] AV-45, Florpyramine, [18F] Florbetapir.
A suitable and standardized protocol depending on the radiopharmaceutical used together with technical precautions and good communication with the client, contribute to the good quality of the service offered, both in terms of efficacy and safety of the treatments.
It is important to have a professional attitude aimed at active listening, to formulate short, precise sentences, composed of simple and clear words, to speak slowly and to give time to respond. The patient with demented syndrome needs a relaxed and non-judgmental environment.
Current PET / CT on the market are equipped with tools such as automatic exposure control and iterative algorithms, useful for reducing and optimizing the radiation exposure, the scan parameters may vary depending on the type of scanner. In clinical practice it is commonly used to use 120 KV and 60-100 mA, to obtain a suitable attenuation map and morphological localization. The PET scan is reconstructed using a 256 × 256 matrix using an iterative algorithm with a Gaussian low-pass filter. Both PET and CT data are constructed with a 25-30cm FOV.
CONCLUSIONS
The radiopharmaceuticals currently available must be known for their respective specifications by the technologist, in order to guarantee the correct acquisition and compliance with the exam timing. An adequate implementation of technical skills and soft communication skills makes an appropriate context for the delicate balance of AD patients, having the patients and their specific needs at the center of health care.
Downloads
Dettagli dell'articolo
Gli autori mantengono i diritti sulla loro opera e cedono alla rivista il diritto di prima pubblicazione dell'opera, contemporaneamente licenziata sotto una Licenza Creative Commons - Attribuzione che permette ad altri di condividere l'opera indicando la paternità intellettuale e la prima pubblicazione su questa rivista.
Riferimenti bibliografici
[2] Ashford JW, Salehi A, Furst A, Bayley P, Frisoni GB, Jack CR, Jr., et al. Imaging the Alzheimer brain. J Alz-heimers Dis 3: 1-27. (2011)
[3] Fong P. C., Khuen Y. N., RhunY.K. ,Soi M. C. Tau Proteins and Tauopathies in Alzheimer's Disease. Cellular and molecularneurobiology. 2018 Jul; 38(5):965-980
[4] N. Scott Mason, Chester A. Mathis, and William E. Klunk. Positron emission tomography radioligands for in vivo imaging of Aβplaques . (2013)
[5] Fondamenti di medicina nucleare. Tecniche e applicazioni. D. Volterrani, P. A. Erba, G. Mariani. (2010)
[6] Braak H, Braak E. Frequency of stages of Alzheimer-related lesions in different age categories. NeurobiolAging 18(4): 351-7.(1997)
[7] Riassunto delle raccomandazioni del Gruppo di Lavoro Intersocietario Italiano per l’Utilizzo dell’Imaging di Ami-loide nella Pratica Cinica. A cura del GdS di Neurologia dell’AIMN. *Libera traduzione di Ambra Buschiazzo e Silvia Morbelli dall’originale Guerra UP, Nobili FM, Padovani A, Perani D, Pupi A, Sorbi S, Trabucchi M. Recom-mendations from the ItalianInterdisciplinary Working Group (AIMN, AIP, SINDEM) for the utilizationofamyloidima-ging in clinical practice. Neurol Sci. 2015 Jan 24. [Epub ahead of print]; PMID:25616445)
[8] Wang H, Guo X, Jiang S, Tang G. Automated synthesis of [18F] Florbetaben as Alzheimer's disease imaging agent based on a synthesis module system. ApplRadiatIsot 71(1): 41-6. (2013)
[9] Hiltunen M, van Groen T, Jolkkonen J. Functional roles of amyloid-beta protein precursor and amyloid-beta pep-tides: evidence from experimental studies. J Alzheimers Dis 18(2): 401-12. (2009)
[10] Buccino P., Savio E., Williams P.Fully -automated radiosynthesis of the amyloid tracer [11C] PiB via direct [11C]CO2 fixation-reduction. EJNMMI Radiopharmacy and Chemistry volume 4, Article number: 14 (2019)
[11] Brain PET Scan: study protocol of dementia De Rosa Salvatore, Beneduce Carmela, Cuocolo Alberto, Gallo Giada. (2020)
[12] Lide D. CRC Handbook of Chemistry and Physics. 76th edition ed. USA: CRC Press, Inc. (1995)
[13] https://www.aimn.it/documenti/lineeguida/16_RP_AIMN_neuro.pdf consultato il 18/03/2022
[14] Patt M, Schildan A, Barthel H, Becker G, Schultze-Mosgau MH, Rohde B, et al. Metabolite analysis of [18F]Florbetaben (BAY 94-9172) in human subjects: a substudy within a proof of mechanism clinical trial. J RadioanalNuclChem 284: 557–62. (2010)
[15] Mason NS, Mathis CA, Klunk WE. Positron emission tomography radioligands for in vivo imaging of Abeta plaques. Journal of labelled compounds & radiopharmaceuticals 56(3-4): 89-95. (2013)
[16] Zhang W, Oya S, Kung MP, Hou C, Maier DL, Kung HF. F-18 Polyethyleneglycol stilbenes as PET imaging agents targeting Abeta aggregates in the brain. Nucl Med Biol 32(8): 799-809. (2005)
[17] http://www.piramal.com/imaging/pdf/Final-U-Approval-pr.pdf. (2014) consultato il 18/03/2022
[18] Radiotracers for Amyloid Imaging in Neurodegenerative Disease: State-of-the-Art and Novel Concepts Angelina Cistaro, Pierpaolo Alongi, Federico Caobelli and Laura Cassalia Current Medicinal Chemistry, 2018, 25, 3131-3140
[19] N. Belcari, A. Del Guerra, Il tomografo PET e PET/TC. In: Volterrani D, Erba P. A., Mariani G. a cura di. Fon-damenti di medicina nucleare, Springer; 2010. p. 274-275
[20] https://www.nurse24.it/specializzazioni/management-universita-area-forense/migliorare-qualita-comunicazione-sanita.html consultato il 18/03/2022
[21] Ceriani L., Suriano S., RubertoT., Giovanella L.Could Different Hydration Protocols Affect the Quality of 18F-FDG PET/CT Images. Journal of Nuclear Medicine Technology. June 2011, 39 (2) 77-82
[22] Pragmatica della comunicazione umana. Studio dei modelli interattivi, delle patologie e dei paradossi. Paul Watzlawick (Autore), J. H. Beavin (Autore), D. D. Jackson (Autore), M. Ferretti (Traduttore). Casa Edittrice Astrolabio 1978
[23] Vigorelli P. Alzheimer, Come favorire la comunicazione nella vita quotidiana. Milano: Edizioni Franco Angeli; 2015
[24] Flin R., O’Connor P., Crichton M., Safety at the Sharp End - A guide to Non-Technical Skills. Burlington (USA): Ashgate Publishing Company; 2008
[25] Vigorelli P. (2007): Dalla Riabilitazione alla Capacitazione: un cambiamento di obiettivo e di metodo nella cura dell'anziano con deficit cognitivi. Geriatria, 4, 31-37.)
[26] Garcia-CasaresN., Moreno-Leiva M.R., Garcia-Arnes A. J. Music therapyas a non-pharmacological treatment in Alzheimer'sdisease. A systematic review. Rev Neurol. 2017 Dec 16;65(12):529-538.
[27] Sureshbabu W., Mawlawi O. PET/CT imaging artifacts. J NuclMedTechnol. 2005 Sep;33(3):156-61
[28] Gould S.M., Mackewn J., Chicklore S, Cook J.R.G., Mallia A., Pike L. Optimisation of CT protocols in PET-CT across different scanner models using different automatic exposure control methods and iterative reconstruction algorithms. EJNMMI Phys. 2021 Jul 31;8(1):58.
[29] A Burger I., A ScheinerD., W Crook D, Treyer V., F Hany T.,K von Schulthess G. FDG uptake in vaginal tamponsis caused by urinary contamination and related to tampon position. Eur J Nucl Med Mol Imaging. 2011 Jan;38(1):90-6.)
[30] Camoni L, PesteanC, Testanera G, Costa PF. Basics for nuclear medicine image reconstruction, Reference Module in Biomedical Sciences, Elsevier, 2022, ISBN 9780128012383
[31] Cooke, C.D., Faber, T.L., Galt, J.R., 2011. Fundamentals of image processing in nuclear medicine. In: Khalil, M.M. (Ed.), Basic Sciences of NuclearMedicine. Springer Berlin Heidelberg, Berlin,Heidelberg, pp. 217–257.