What is Angiography ?
Angiography or arteriography is a medical imaging technique to visualize the inside or lumen of the blood vessels and organs of the body, with particular interest in the heart’s arteries, veins and chambers. This is traditionally done by using X-ray-based techniques such as fluoroscopy to inject a radio-opaque contrast agent into the blood vessel and imaging.The word itself comes from the Greek word angeion , “ vessel “ and graphein , “ to write or “ record ”. An angiograph or more commonly an “angiogram” is called the film or image of the blood vessels.
Types of angiography
Actually the term angiography is strictly defined as projectional x-rays, the term has been applied to new vascular imaging techniques such as CT angiography and MR angiography.
CT angiography is a Computed Tomography angiography ( CTA ) technique used to visualize arterial and venous vessels throughout the body . This ranges from brain to arteries that carry blood to the lungs, kidneys, arms and legs.
Benefits of CTA
CTA can be used in many key areas of the body, including the brain, kidneys, pelvis and lungs, to examine blood vessels.
Some benefits are as follows :
• The procedure can detect narrowing blood vessels in a timely manner for corrective therapy.
• This method shows blood vessel anatomical details more accurately than MRI or ultrasound.
• Instead of a conventional catheter angiogram, many patients may experience CTA
• CTA is useful ways of screening for arterial disease because it is safer and much less time consuming than catheter angiography and is a cost effective procedure.
• Less discomfort is also caused by the injection of contrast material into the arm vein rather than into the groin’s large artery.
Risks of Angiography (CTA)
CTA also have several risks which may be serious . Some of them are :
• If iodine-containing contrast material is injected, there is a risk of an allergic reaction. A patient with a history of allergy of X– ray dye may be advised to take special medication 24 hours prior to CTA to reduce the risk of allergic reaction or to undergo another examination that does not require injection of contrast material.
• CTA should be avoided in patient with kidney disease or severe diabetes, because X ray contrast material can further harm kidney function .
• If a large amount of X-ray contrast material leaks under the skin where the IV is placed, damage to the skin may occur.
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What is Nano – Sensor ?
The sensors are made up of thin filaments of carbon molecules known as carbon nanotube. Several teams are using nanomaterials – thousand of times smaller than the width of human hair- to develop new ways to deliver drugs in the body or improve diagnosis of disease. For its sensors , Strano’s team wrapped carefully shaped carbon nanotube with DNA, which offers a binding site for DNA damaging agents inside cells.
The sensors provide a fluorescent light that can be detected in the spectrum of near-infrared light. Because in this spectrum human tissues are not illuminated, the nanotubes stand out. When the sensors interact with DNA inside the cells, the light signal changes. These changes can assist them in identifying specific molecules.
• It is a way of fingerprinting chemistry.
• Because the sensors are coated in DNA , they can be safely injected into living cells.
• Eventually the cell eats the protein off the coating and it essentially splits it out.