Table 1.

Role of imaging in infectious diseases

Advantages of tomographic imaging over traditional techniques used for infections
Evaluate disease processes deep within the body, noninvasively, and relatively rapidly
Longitudinal assessments in the same individual—fundamental advantage over traditional tools
Provide holistic, three-dimensional assessment of the whole organ or body representative of the overall disease (versus tip of a biopsy needle) and therefore less prone to sampling error
Imaging in infectious diseases
Role	Setting	Overall goal(s)
Pathogenesis	Preclinical	Unique insights into disease pathogenesis, e.g., assessing hideouts of infections, defining the diversity of the microbial populations (microbiome) Studying multi-compartment antimicrobial pharmacokinetics Expedite bench-to-bedside translation of new therapeutics, e.g., surrogate end points to assess antimicrobial or vaccine efficacy or predict stable cure
	Clinical trials	Unique insights into disease pathogenesis—noninvasive visualization of processes deep inside the body Phase 0 studies to determine compartment-specific antimicrobial penetration/binding (sites of infection, necrotic/fibrotic lesions, privileged sites—CNS) to inform appropriate dosing of novel drugs; determine accumulation at non-target sites to assess potential toxicities; current US Food and Drug Administration (FDA) guidelines require tissue drug distribution studies at the infected sites
	Patient settings	Enabling precision medicine by providing unique insights into disease pathogenesis, antimicrobial pharmacokinetics, etc.
Diagnosis	Clinical trials and patient settings	Rapidly and specifically distinguish an infectious process from other diseases (malignancy, sterile inflammatory processes, etc.) Determine the site (e.g., extension/metastasis to other organs or privileged sites) and extent of disease Provide information on the class of the infectious pathogen, which could help in targeted empiric antimicrobial treatments
Monitoring and prognostication	Preclinical	Noninvasive longitudinal assessments, especially in studies utilizing larger, more expensive animal species; serial assessments in the same animal could significantly reduce sample size, inter-animal variability (outbreed animals), and therefore cost of the studies
	Clinical trials	Early end points for treatment trials to assess activity of treatments and to predict stable cure Assessing host-directed treatments for infections Enable adaptive designs
	Patient settings	Rapidly detect treatment failures due to drug-resistant organisms or other reasons Rapidly monitor treatment responses in patients with drug-resistant organisms and individualize treatments Early end points for duration of treatment and predict stable cure enabling precision medicine
	Public health	Rapid determination of the infectious risk of a patient to the population based on response to treatment and extent and location of disease Rapid diagnosis and monitoring of biothreat agents