Table 1.

Overview of different in vivo imaging modalities along with their pros and cons

Imaging modality		Pros	Cons
Optical imaging	BLI	- High sensitivity - High signal to noise ratio - Low background signal in small animal models	- Limited imaging depth - Non-mammalian origin of luciferase causes immunogenicity issues in large animal models
	FLI	- Low cost - Can track multiple different probes in vivo simultaneously	- Limited imaging depth - Poor spatial resolution
	IVM	- High resolution - Understand interaction of cells in TME	- Limited imaging depth
	OCT	- High resolution - Fast scan times - 3D images	- Limited imaging depth - High cost
X-ray/CT		- No depth limitation - Anatomical information - Whole body imaging - Faster scan times compared to MRI	- Exposure to ionizing radiation - Lower soft tissue contrast compared to MRI
PET		- No depth limitation - High sensitivity - Whole body imaging	- High cost - Exposure to ionizing radiation - Lower accessibility than SPECT
SPECT		- No depth limitation - Whole body imaging - Greater accessibility than PET	- Exposure to ionizing radiation - Lower sensitivity than PET
MRI		- No depth limitation - Anatomical information - Whole body imaging - High resolution - Better soft tissue contrast compared to CT	- High cost - Lower sensitivity than PET/SPECT - Long acquisition times
US/PA		- High spatial resolution - Multiplexing capabilities - Anatomical information from ultrasound	- Limited penetration depth