Fluoroscopy

Purpose:
Fluoroscopy is the method that provides real-time X ray imaging that is especially useful for guiding a variety of diagnostic and interventional procedures. The ability of fluoroscopy to display motion is provided by a continuous series of images produced at a maximum rate of 25-30 complete images per second. This is similar to the way conventional television or video transmits image.

Principles:
In fluoroscopy, as in all types of X ray imaging, the minimum exposure required to form an image depends on the specific image information requirements.An important characteristic of a fluoroscopic system is its sensitivity, i.e. the amount of exposure required to produce images. The use of intensifier tubes and more modern digital flat panel receptors make it possible to optimize the balance of patient exposure with image quality so as not to expose the patient to unnecessary radiation. Non-intensified fluoroscopy with just a fluorescent screen for a receptor should not be used because of the excessive exposure to the patient.


Equipment:



Application:
Fluoroscopy is used in many types of examinations and procedures, such as barium x-rays, cardiac catheterization, and placement of intravenous (IV) catheters (hollow tubes inserted into veins or arteries). In barium x-rays, fluoroscopy allows the physician to see the movement of the intestines as the barium moves through them. In cardiac catheterization, fluoroscopy enables the physician to see the flow of blood through the coronary arteries in order to evaluate the presence of arterial blockages. For intravenous catheter insertion, fluoroscopy assists the physician in guiding the catheter into a specific location inside the body.

Linear Tomography

Purpose:
X-ray images are collected while the X-ray tube moves through arange of positions, generating images with a range of exposure angles. For example, a standard doctor’s office or small clinic X-ray machine has a movable X-ray tube. Collecting images with exposure angles spanning at least 60o with respect to the subject is desirable.

Principles:
In spite of costs and safety concerns, existing Linear Tomography machines employ the alternative of precisely controlling motion with motor-driven equipment. In this approach, precise knowledge of X-ray tube position and orientation (Pose) is achieved by building a precision machine and making one displacement measurement at each joint of the machine.

Because of the cost of precisely controlling motion of the X-ray tube and subject, the Iconos R 200 is considerably more expensive than a manually moved X-ray machine (one GEMS manager estimates $100K added for the cost of the high-precision X-ray tube motion system). In addition to cost, the automated X-ray tube motion system adds considerable size, weight and complexity to a Linear Tomography system, such as the Iconos R 200.

Equipment:



















Application:
For obtaining clear x-ray images of deep internal structures by focusing on a specific plane within the body. Structures that are obscured by overlying organs and soft tissues that are insuffi ciently delineated on conventional x-rays can thus be adequately visualized