Medical Imaging file formats

A medical image represents the internal structure or function of an anatomic region in the form of pixels or voxels (value on a regular grid in a three-dimensional space). 

Ultrasound

• High-frequency sound waves  transmitted from the probe to body via a conducting gel

• Waves  bounce back when they hit the different structures within the body - used to create an image for diagnosis.

CT (Computed Tomography)

• Form of X-ray that creates a 3D picture for diagnosis: produce cross-sectional images of the body

• X-ray source and a detector then rotate around the patient producing a narrow ‘fan-shaped’ beam of X-rays that passes through a section of the patient’s body

• Different snapshots collated into one or multiple images of the internal organs and issues.

PET (Positron Emission Tomography)

• Nuclear medical imaging 

• Uses small amounts of radioactive materials, a special camera and a computer to evaluate organ and tissue functions

• Tracer is given through a vein (IV). 

MRI (Magnetic Resonance Imaging)

• Uses magnetic field and radio waves to generate images of body

• Protons aligned in magnetic field

• Scanner uses magnetic field to align proton spins, followed by a radio frequency being applied to flip spins of protons before they return to original alignments

• Protons in different body tissues return to normal spins at different rates

  • MRI can distinguish between different tissue types

X-Ray

• X-rays penetrate skin and create image of internal structures

Slicer

• open source software platform for medical image informatics, image processing, and three-dimensional visualization

TomViz

• cross platform, open source application for the processing, visualization, and analysis of 3D tomographic data

The Cancer Imaging Archive

• large archive of medical images of cancer accessible for public download

• sorted by collection

• MRI/CT/digital histopathology

BraTS

• manually-segmented MRI scans of glioblastomas