Radioisotopes for Diagnosis

Atom Medicine

CT Scan and MRI Introduced

Organ Transplantation

In 1967 surgery arrived at a climax that made the whole would aware of its medicosurgical responsibilities when the South African surgeon Christian Barnard transplanted the first human heart.

In 1964 James Hardy, of the University of Mississippi, had transplanted a chimpanzee’s heart into a man.

Research had been remorselessly leading up to just such an operation ever since Charles Guthrie and Alexis Carrel, at The University of Chicago, perfected the suturing of blood vessels in 1905 and then carried out experiments in the transplantation of many organs, including the heart.

The use of X-rays in medicine was a huge breakthrough at the turn of the century. British engineer Godfrey Hounsfield came up with an improvement on the 70-year-old technology. It combined X-ray images with a computer.

Hounsfield called this technology a CT (computerized tomography) scan, also called CAT scan (computerized axial tomography). It was especially useful for looking at head injuries and brain problems, because it showed about 100 times greater detail in soft tissues than traditional X-rays. Hounsfield was knighted and won the 1979 Nobel Prize.

In the 1980s another imaging technique was added to the tools of medicine. Nuclear magnetic resonance is a technology that, using a gigantic magnet, can line up the protons- or nuclei of hydrogen atoms – in an object (or organism) to align with the north-south polarity of the magnet. A computer “reads” this to create an image in a process known as MRI, magnetic resonance imaging. MRI can give an image of any plane through the body, while the patient’s experience consists of lying still in a body-sized tube, and hearing the click of the machinery.

In the last 20 years the use of atom medicine has become so widespread that every big medical centre uses some form of it in diagnosis and treatment. Thousands of hospitals all over the world have had very successful results with radioactive iodine for thyroid cases.

The chief medical use of radioisotopes is against cancer. Every year thousands of cancer patients are being treated with radio-cobalt, which in many ways is better than X-ray treatment.

The radioisotopes can be given in smaller doses, and can be concentrated more accurately on the cancerous cells. In addition, they cannot cause burns and have no harmful radiation effect.

In some cases it is important for the surgeon to know whether an injured bone has “dead” from loss of blood supply.

Few years ago it was necessary to wait several months, and sometimes even a year, for the accurate diagnosis that made treatment possible. Now surgeons have discovered how to find in a few minutes whether the bone has ‘died”. It is done by using a radioscope – Sodium 24. When this isotope is pumped into the injured bone, it keeps its radio-activity if the bone is “dead”. But if the bone is still living, the blood carries away the radioisotope within ten minutes.

By measuring the amount of radio-activity left in the bone, the surgeon gets the information about the condition of the injured bone.

Дата добавления: 2014-12-29