Spine Radiograph

The most common and well-known imaging technique (aka modality) in radiology is the conventional radiograph, or "plain film." An x-ray machine creates images by directing ionizing radiation (gamma rays) through a patient's body toward a detector (photosensitive plate).  The gamma rays are either absorbed or reflected by different tissues and bones within the body. Those not absorbed are captured by the detector and processed into a digital format, resulting in the radiograph image.

Dense tissues like bone absorb more x-rays, appearing bright or white on the radiograph, while less dense tissues like the lungs or skin allow more x-rays to reach the detector, appearing dark or black. In the accompanying image, you can observe how the bones and metal earrings appear brighter than other tissues. 

Indications: common indications for spine radiographs include evaluation of spinal fractures, degenerative disorders,  alignment abnormalities such as scoliosis, procedure guidance or localization in the operating room, and confirming or evaluating hardware placement.

Advantages: speed, simplicity, relative affordability, portability, and widespread availability in most healthcare settings.

Disadvantages: use of ionizing radiation, although the amount is generally considered negligible compared to background radiation from natural sources. Additionally, it provides only a 2D image, which may require multiple views for precise localization, and has a limited range of densities compared to more advanced imaging modalities like CT and MRI.