No abstract

Alzheimer's disease (AD) is a progressive neurodegenerative disorder and the most common cause of dementia. Beta-amyloid (Aβ) deposition and neurofibrillary tangles (NFTs) of abnormal hyperphosphorylated tau protein are the pathological hallmarks of the disease, accompanied by other pathological processes such as microglia activation. Functional and molecular nuclear medicine imaging with single-photon emission computed tomography (SPECT) and positron emission tomography (PET) techniques provides valuable information about the underlying pathological processes, many years before the appearance of clinical symptoms. Nuclear neuroimaging in AD has made great progress in the past two decades and has extended beyond the traditional role of brain perfusion and glucose metabolism evaluation. Intense efforts in radiopharmaceuticals research have led to the development of various probes able to detect Aβ deposits, tau protein accumulation, microglia activation and neuroinflammation. As a result, SPECT and PET have proposed to serve as biomarkers in recently revised diagnostic clinical criteria for the early diagnosis of AD and the prediction of progression to AD in mild cognitive impairment (MCI) subjects.

The use of cardiac PET, and in particular of quantitative myocardial perfusion PET, has been growing during the last years, because scanners are becoming widely available and because several studies have convincingly demonstrated the advantages of this imaging approach. Therefore, there is a need of determining the procedural modalities for performing high-quality studies and obtaining from this demanding technique the most in terms of both measurement reliability and clinical data. Although the field is rapidly evolving, with progresses in hardware and software, and the near perspective of new tracers, the EANM Cardiovascular Committee found it reasonable and useful to expose in an updated text the state of the art of quantitative myocardial perfusion PET, in order to establish an effective use of this modality and to help implementing it on a wider basis. Together with the many steps necessary for the correct execution of quantitative measurements, the importance of a multiparametric approach and of a comprehensive and clinically useful report have been stressed.

Our findings suggest that leptin, adiponectin, and ghrelin may play a significant role in the pathogenesis of asthma during both stable state and asthma exacerbation, independent of obesity.