Book Review: WHO manual of diagnostic imaging: radiographic technique and projections
This book, produced by the World Health Organization in collaboration with the International Society of Radiology (ISR), is a useful and practical manual of general radiography. It is aimed primarily at radiography students and newcomers to the profession but may also be used as additional reading in radiography courses.
By S. Sandstrom
133 pages, 2003, ISBN 92 4 154608 5
Price: Fr40 (Swiss) or US$36 (Fr28 in developing countries)
Order no. 1150540. Available from www.who.int/bookorders/index.htm.
This book, produced by the World Health Organization in collaboration with the International Society of Radiology (ISR), is a useful and practical manual of general radiography. It is aimed primarily at radiography students and newcomers to the profession but may also be used as additional reading in radiography courses.
The manual has a modern layout. Educational information is conveyed through illustrations and text. A pocket edition in which each theme is covered in two pages might be more practical, however, for individual everyday use.
A computer animation technique has been used to show patient positioning. The general position for each radiographic examination is shown clearly. A second illustration shows the area of interest in more detail, pinpointing the precise entrance point of the x-ray beam. An example of the standard radiographic finding is also included on each page. Accompanying comments offer practical tips and stress important factors relevant to each acquisition.
Descriptions of imaging methods are accompanied by advice on patient management. The manual could have included comments or instructions on patients' radiation protection here as well. Suggestions on cassette and film dimensions when imaging adults and children will be of particular use to radiography students and beginners.
The most valuable part of the text is the basic technical data. Choice of technical parameters and conditions for performing imaging are crucial parts of good radiographic technique. A high-voltage technique, for instance, is preferable for good-quality images and reduced patient radiation exposure. Students will learn from theoretical explanations for lack of sharpness and low contrast, while these sections should serve as a refresher for more experienced practitioners.
Exposure value tables, containing mAs and kV values, appear alongside projection descriptions. Two options for x-ray intensifying screens are discussed: the "green" system (gadolinium oxysulfide), and the (cheaper) "blue" system (calcium-tungstate). The manual's explanation of how to calculate combined screen-film speed is not as clear as it could be. The implications of changing kV on image contrast (scattered radiation) and screen-film speed (k-edge) are stressed in the text, however. Practical advice on when to use a grid or when to position a cassette beneath the imaged body part is also provided.
This manual outlines an extremely basic spectrum of radiography projections for x-ray imaging of adults and children. Publication of a companion volume describing the many other projections used routinely would also be worthwhile.
Dr. Zoran Klanfar
Radiologist and lecturer
Sisters of Mercy Clinical Hospital
Zagreb, Croatia