= Interventional radiology
\b[Interventional radiology] uses medical imaging to guide instruments into the body for diagnosis or treatment. A <biopsy> can obtain material for diagnosis; a <catheter> can provide access for a therapeutic procedure. Guidance may use <fluoroscopy>, <ultrasound>, <computed tomography> or <magnetic resonance imaging>, depending on the instrument, target and procedure.<Professions in Interventional Radiology by RadiologyInfo.org>[Interventional Radiologist: imaging modalities, needles/catheters and diagnostic/therapeutic procedures.]{ref}
The central measurement problem is localization. In an image-guided <biopsy>, seeing a suspicious region and seeing a needle separately is insufficient: the operator needs evidence that the sampling part of the needle reaches the intended region. A single <X-ray> projection collapses depth, so two objects can overlap on the image while remaining separated in the body. Choosing imaging views and following instrument motion addresses that geometric uncertainty. This explains why image guidance is more than taking a picture before an intervention.
An early therapeutic motivation was to use the access already provided by arterial <catheters> to treat obstructed vessels. <Charles T. Dotter> and <Melvin P. Judkins>'s 1965 report described a percutaneous transluminal approach to arterial obstruction. Its developmental discussion connected contrast examinations and observed catheter pathways with the possibility of opening a passage through an obstructed region.<Percutaneous Transluminal Treatment of Arteriosclerotic Obstruction by Charles T. Dotter and Melvin P. Judkins>[Abstract and Developmental Background, Figures1–2.]{ref}
The example connects anatomical imaging to mechanical action: identifying a narrowed path and changing that path are different tasks, but the same image-guided access can support both. The historical report motivates the method; it is not a procedure-selection rule for an individual patient.
Back to article page
