Fundamentals benefit image reading

Rinckside 2002; 13,1: 1-3.

he title of a Rinckside column that appeared in 1994 was Medical ethics and the military [1]. It be­gan as follows:

“Woolsorters' disease has a rapid onset. It leads to rigor, rapid respiration, pain in the chest, rapid and feeble pulse, high temperature, usually with cough and bronchitis. Much frothy mucus is produced. Extreme collapse and death occurs in one to three days. The mind usually remains clear.

“Woolsorters' disease is caused by the anthrax bacillus. It used to be a disease of farmers, veterinarians, and slaughterhouse workers. You can also use this bacillus for bacterial warfare.

“Bomblets can be packed with billions of anthrax spores. As spore, anthrax becomes easy to handle. Once again in an airy, moist, and warm environment the spore turns back into its old self. … [In World War II] the British calculated that 2,690 bomber sorties would be sufficient to eliminate the entire population of Germany, their war enemy at the time.”

I received four or five comments from readers in response to this particular column shortly after its publication. By autumn 2001, the topic had been all but forgotten.

   Then, suddenly, anthrax and an accompanying anthrax hysteria broke out in the United States and elsewhere. Imaging anthrax became a hot topic at the annual meeting of the RSNA, held in Chicago, just ten weeks later. The US Armed Forces Institute on Pathology, together with two other institutes, reacted quickly and put an excellent site on CT and anthrax on the world-wide web [2].

“The tool is particularly timely because doctors may see a number of patients during the upcoming flu season who are worried that they may have contracted anthrax, which has flu-like symptoms [3]," one medical journalist wrote.

Many people believe that inhalation anthrax is a tropical disease. Naturally happening human anthrax infections are very uncommon in Europe and the Americas, if the spores are not used for sinister purposes. Anthrax is more common in Africa and Asia, although even there it is a rare disease nowadays. Inhalation anthrax can cause hemorrhagic mediastinitis that radiologically is characterized by symmetric mediastinal widening. This can be seen on a plain chest x-ray.

Using CT for its diagnosis would be considered unrealistic in most parts of the world where diagnostic imaging looks completely different from the sophisticated applications in CT, MRI, ultrasound and nuclear medicine we are used to.

   Some recent publications of the World Health Organization help to understand the needs of basic imaging and the interpretation of x-ray images in daily routine. These publications explain that any imaging procedure, regardless of type and degree of sophistication, will have a positive effect on patients only when seen in a clinical perspective, and that any diagnostic efforts are justified only when followed by appropriate therapeutic measurements. Where possibilities for treatment are limited, diagnostic efforts might be limited accordingly. Where certain diseases are of no or minor importance, imaging equipment for such diseases is superfluous – even if you have all the oil money of the world. If there are potentially better diagnostic and therapeutic chances elsewhere, the patient should be transferred.

In many developing (and developed) countries patients have come to believe that no clinical examination by their doctor is complete unless they have been “x-rayed”. The actual procedure is satisfying because it is usually dramatic, yet causes little discomfort or inconvenience. Yet, wherever you are, as a medical doctor one should not sell x-rays as witchcraft or placebo. Such imaging procedures should be restricted, if possible, despite pressure from patients and their relatives who are not easily persuaded that an x-ray is unnecessary.

More than 15 years have passed since WHO first published a booklet on x-ray imaging [4] which I found extremely helpful at a time when I prepared for (and passed) my radiological board examination.

Most European or US-American radiological teaching books of that period (and most likely today) were very good but, unfortunately, paid little attention to basic radiology. Even if you work at a European university hospital you should be able to interpret a simple thorax or wrist image. However, this seemed to be a less deserving topic unworthy of the authors of those radiological teaching books I used. Interpretations of the shadowgram of the heart seemed to be more relevant. In the meantime, heart x-rays have all but disappeared from diagnostic radiological routine; thorax and wrist examinations are still very much de rigueur.

WHO books teaching the basics of radiology represent a useful addition to radiological literature.

It is here where the WHO booklet comes in very handy. Many countries do not have adequate radiological services, and some have none at all. Over 90% of diagnoses requiring diagnostic imaging can be satisfied if there is basic, general-purpose x-ray and ultrasound equipment in place and functioning.

In most countries of this world x-rays are not taken or interpreted by radiologists, and this actually holds true for many European countries as well. Clinicians or even technicians are mostly in charge; they are working in small hospitals or clinics with limited resources and usually without any possibility of contact with a radiologist or other medical staff specially trained in diagnostic imaging. Training of health care professionals in medical imaging should not only focus upon acquiring and reading images but also include some managing and repairing skills. All these skills should be tailored to local needs. Again, the WHO booklets help in these instances.

They also give the imaging practitioners a black-on-white back-up for referrals such as “low back pain: whole column in all projections” or “headache: skull”. They can show the referring physician that such examinations are not medically justified. However, on the other hand, it is also pointed out that in addition to a solid knowledge about what is relevant and what might not be, an open-minded communication between clinician and radiologist or radiological technician is a fundamental requirement for medical success in this context. In any case, the clinical examination should come first and given priority. X-rays and blood test before the clinician sees the patient should be exception, not the rule.

   In Europe and the English-speaking countries of North America there are usually enough radiologists at hand. Yet, more than half of all x-ray examinations are performed by non-radiologists. This leads to an enormous increase in unnecessary x-ray examinations and false interpretations. In Germany, at least 25% of all x-ray examinations are considered to be of insufficient quality – and the results are often wrong. The financial damage is several billion euros. The human damage is unknown.

Two main factors are pivotal in radiodiagnostic investigations: quality assurance and accurate interpretation of x-ray images. This holds for both developed and developing countries. However, in developed countries quality control and knowledge to interpret images can be easily acquired and learned. There is plenty of help and teaching material available. Unawareness, laziness, lack of supervision, and – last but not least – financial reasons limit medical excellence.

In developing countries this might be the case too, as it is only human. However, the main factor is lack of teachers and teaching material. Brochures, books, and teaching courses which may look and sound ridiculously simple and cheap to Europeans, can make all the difference in countries where medical resources are scarce. Basic teaching booklets, for instance, are a god given resource. The two latest ones published by WHO deal with quality assurance and recognition of normal anatomical and physiological appearances on x-ray images and changes that indicate pathology [5,6].

A lack of teachers and material is the main obstacle to quality control in developing nations – and not only there.

Dr. Harald Østensen, the head of Diagnostic Imaging at WHO, writes in the preface to WHO’s Pattern Recognition in Diagnostic Imaging:

“We would warmly recommend that this book should not be put on a shelf or into a locker, but be used by everybody whose obligation it is to prescribe, perform, or interpret simple, but often life-saving diagnostic imaging procedures especially in locations where the presence of qualified and fully trained specialists would be a rare exception.”

I call them booklets, but in reality these are handy A4-size books with more than 200 pages written for settings where resources are sparse. Although this column is not a book review I wholeheartedly endorse Harald Østensen’s commendation because the books are well made, inexpensive, and belong to the limited number of radiological teaching and textbooks which will find a broad public – and still be up-to-date ten years from now.

In a leaflet accompanying the books and aimed at the books’ main target region of the world, the objectives are summarized:

“Diagnostic imaging can directly benefit people living with HIV/AIDS and tuberculosis or exposed to accident and trauma by establishing correct diagnoses and providing adequate information on effect of treatment. Reduced morbidity and mortality impact directly on national economies, by prolonging lives, enabling professional activity, and assuring that families are sustained by active members. Indirectly, decreased burden of disease affects the frequency of medical consultations, absence from the work­place, unemployment figures and overall social expenditure.”

These are dry words, but worthwhile to be taken into account by what is called “the public and private sectors” allocating resources for healthcare.

By the way, they do not propose CT to distinguish anthrax from flu (no sarcasm meant).

References

1. Rinck PA. Medical ethics and the military. Rinckside 1994; 5,2: 3-4.
2. Galvin JR and collaborators. Inhalation anthrax. http://anthrax.radpath.org [might have been taken off the web].
3. Wagner KL: CT plays important role in anthrax detection. Diagnostic Imaging.com webcast. RSNA 2001. http://www.diagnosticimaging.com/cgi-bin/webcast01 [might have been taken off the web].
4. Palmer PES, Cockshott WP, Hegedüs V, Samuel E. World Health Organization Basic Radiological System. Manual of radiographic interpretation for general practioners. WHO: Geneva. 1985.
5. Corr P and collaborators. Pattern recognition in diagnostic imaging. WHO: Geneva. 2001.
6. Lloyd PJ. Quality assurance workbook for radiographers and radiological technologists. WHO: Geneva. 2001.

Citation: Rinck PA. Fundamentals benefit image reading. Rinckside 2002; 13,1: 1-3.

A digest version of this column was published as:
Fundamentals benefit image reading.
Diagnostic Imaging Europe. 2002; 18,3: 13-15.