TAKE a deep breath,” the disembodied voice of the radiographer instructs me.
I am standing in the x-ray room, dressed in a standard hospital gown. Outside the room, the red light above the door is illuminated, barring entry during the procedure.
A few moments later, I’m told to get dressed and wait for the results.
X-rays and other modern imaging techniques like CT and MRI scans are nothing short of a medical revolution, says Assoc Prof Dr Basri Johan Jeet Abdullah, consultant radiologist and president of the College of Radiology, Academy of Medicine, Malaysia.
“Before x-rays, the only way to look inside the human body was when the guy was dead, and you cut him open,” he points out with the sort of pride that only radiologists would be able to identify with.
In 1895, a German physicist named Wilhelm Roentgen changed the face of medicine when he accidentally took an x-ray image of his own hand. The following x-ray picture taken, that of his wife’s hand, has become widely accepted as the image defining the discovery of x-rays.
Our conversation is interrupted by a doctor who asks Dr Basri for his opinion on the diagnosis of a patient who had undergone a scan earlier.
That a physician would seek Dr Basri’s opinion is an indication of how much the role of radiologists in clinical medicine has changed over the last 10 years. Once upon a time, they were considered mere photographers who took nice pictures.
“The internal physician would come and say ‘show me that picture’,” Schering AG researcher Dr Malte Bahner mimics a slightly contemptuous tone, as his colleagues grin and nod in agreement. “Nobody would take radiologists too seriously.”
Fortunately, this is a perception that has changed in favour of radiologists. Today, they are highly specialised physicians who are able to “look into” the human body and tell what is wrong with a patient.
“Radiology today is a fascinating and fast-growing science with a heavy impact on clinical medicine. The information (from the images) ? has proven important for everyone involved in treating a patient,” says Dr Bahner, who is the head of the Clinical Development Contrast Media division in Schering’s office in Berlin.
The new buzzword in clinical medicine, or at least among radiologists, is “theragnostics”, a combination of therapy and diagnostics.
“The borders (between diagnosis and treatment) are going to become increasingly indistinct,” predicts Dr Basri, who is also head of the radiology department in University of Malaya.
Medical imaging, which can now identify abnormal tissue, such as a tumour, and its location, “can be used as a basis to decide on treatment, because now you know how far the disease (if it is cancer) has spread, what are the complications, how it’s going to change and what you have to do for the patient,” he explains.
Imaging can also be used to monitor a patient’s response to therapy, especially in the case of cancer.
Looking inside the body
Scientific literature may not describe Roentgen’s reaction when he saw the bones of his hand through x-rays for the first time, but one can imagine the amazement he must have felt.
Yet, if Roentgen could see how far medical imaging has progressed today, the x-ray vision of his hand would certainly pale in comparison.
The technology of imaging has evolved to the point that we can now take three-dimensional images of the body, select specific cells for scanning and pinpoint abnormalities with greater accuracy.
“We can (now) look into bodies in a non-invasive way that was not thought possible 10 or 20 years ago,” says Dr Bahner.
Advances in technology have enabled a paradigm shift in medical imaging: from morphology, which looks at the form and structure of the body, to molecular imaging, which “goes to the molecular level to visualise (the body),” says Dr Basri.
Since its discovery, x-rays defined medical imaging for many years. Then the Second World War provided a breakthrough when the ultrasound technology used by submarines was transferred to the medical field. Then came CT (computed tomography), which was able to provide three-dimensional pictures of the body. MRI (magnetic resonance imaging) and PET (positron emission tomography) were developed in the 1980s.
Each of these technologies, which are widely used today, has undergone further improvements that enhance the images produced, particularly with the use of contrast media (the layperson refers to it as “dye”).
Contrast media, such as iodine and barium, work by absorbing radiation so that the areas in which they are injected will show up as white areas. This enables radiologists to tell the difference between normal and abnormal tissue. If a tissue or organ is abnormal, it may look bigger, smaller, brighter or darker compared to normal tissue.
The development of contrast media itself has been undergoing constant change since the first use of it in 1906. Today, contrast agents are developed to be more tissue-specific, such as those that look at certain types of liver cells.
Dr Basri provides the example of gadolinium, which is “now being used to tag to different specific antibodies or antigens, and can tell you where abnormal tissues are.”
Research in contrast media is not only focused on finding new contrast agents, but also agents that are better tolerated by patients, as these substances are ingested or injected into the system.
Some patients are unaware of the tremendous progress that has been made in the field of medical imaging. To them, all imaging tests are x-rays. But there are also patients who are incredibly savvy and come armed with stacks of printed stuff from the Internet.
This is not a bad phenomenon and is, in fact, a step in the right direction because it involves patients in the decision-making process.
“On the downside, however, there is the need to correct some of the wrong perceptions that are ? detrimental to patients’ wellbeing,” remarks Dr Basri.
Some of these perceptions are related to the risk of imaging procedures. Patients are exposed to small amounts of radiation from x-rays and slightly higher amounts in CT scans, while the use of contrast media may carry very low risks of mild to severe reaction.
According to the College of Radiology Malaysia, radiologists and physicians should follow the principle of ALARA (As Low As Reasonably Achievable), which means that “the method selected ? and the steps taken must ensure that the minimum amount of radiation is involved in the process of obtaining good quality diagnostic images ?” notes its website.
Dr Basri points out that imaging, “like life”, is about balancing the benefits derived against its risks. “It is, therefore, very important for the public to be aware that imaging investigations should only be carried out when the perceived benefits exceed the risks from radiation or risk of complications.”
He makes this point because some patients now expect more from imaging than what is possible.
“They would like to have screens of the whole body done because they believe that it can pick up disease earlier. Should patients, who are aware of the risks and limitations, be denied a chance to see if they have any disease?”
He admits that it is a controversial issue that has generated heated debate in the medical community. “I personally feel that this is not the way to go, not at this moment in time.”
Yet who knows what medical imaging will allow us to see in the future? We are only uncovering the tip of the iceberg, and as imaging techniques become more sophisticated, the healthcare paradigm is going to evolve along with it.