Nuclear medicine

echinococcosis (AE) is a potentially life-threatening parasitic zoonosis caused by the larval stages of the fox tapeworm
Echinococcus multilocularis. Transmission of E. multilocularis is document in regions of all continents of the Northern Hemisphere including traditional hotspots of transmission in Central Europe.

Human settlements

An increase in the incidence of human patients with AE has been observed over the past decade Growing fox populations and the establishment of urban fox communities living in close proximity to human settlements in several European countries may be one of the reasons for this observation However, in a Dutch study no increase in human cases was seen despite an increase in E. multilocularis prevalence in foxes.

The disease primarily affects the liver where it shows a tumor-like infiltrative or pseudocystic growth pattern, progressive infiltration, destruction of adjacent anatomical structures and the potential for metastatic spread leading to more than 90% mortality if left untreated Radiologic imaging modalities including ultrasonography, computed tomography (CT)and magnetic resonance imaging (MRI), are important for the diagnostic work up of human AE patients.

Imaging assessing

Therapeutic options include long -term suppressive anthelmintic treatment with or without radical surgical resection. Decisions about the most appropriate therapeutic management are based on the radiological assessment of the disease stage. In addition, radiological long-term follow-up is recommend for all patients to guide further patient management
Over the past decade; CT combined with[ 18F]2-fluoro-2-deoxyD-glucose(18F-FDG) positron emission tomography
(PET) imaging was introduced in clinical routine in affluent health care systems as a novel tool for the initial diagnosis and follow-up of AE .18F-FDG-PET/CT combines anatomical; high-resolution whole-body imaging through CT; with functional imaging assessing regional glucose metabolism provided by FDG -PET .

FDG -PET/CT is routinely use in oncology, neurology, and cardiology; and has further been shown to be useful in the assessment of inflammatory conditions ,. FDG-based PET imaging provides clinically important information about the extent of inflammation in organs affected by AE; as a surrogate marker of parasitic activity that can guide clinical management and treatment decisions.

Viability of lesions

FDG-PET is, therefore, recommend by the WHO informal working group for echinococcosis as a tool with which to assess disease activity in high-resource settings . Because The recent development of whole-body PET/MRI imaging; and its introduction into clinical routine; offers the potential for an alternative dual imaging technique combining PET with high-resolution anatomical imaging by MRI.

This could potentially improve soft tissue differentiation, assessment of the viability of lesions, and consequently lead to improved guidance of therapeutic management. Because Based on the requirement for long -term follow up of AE ; Therefore PET/MRI has the potential to considerably reduce radiation exposure for patients by replacing CT with MRI imaging.

This is of particular importance for younger patients ; as for them the cumulative dose of multiple CT follow up studies can contribute to a non negligible increase in radiation induced cancer risk Here we report the clinical experience of routine imaging studies using PET/MRI imaging for the management; of AE in a cohort of patients with AEat an Austrian reference center.