Introduction

INTRODUCTION

Appropriate surgical management of the patient relies on correct diagnosis. While clinical symptoms and signs may provide a firm diagnosis in some cases, other conditions will require the use of supplementary investigations including imaging techniques. The number and scope of imaging tech niques available to the surgeon have dramatically increased within a generation, from a time when radiographs alone were the mainstay of investigation. The development of ultrasound and colour Doppler , computed tomography (CT) and magnetic resonance imaging (MRI) has enabled the surgeon to make increasingly confident diagnoses and has reduced the need for diagnostic surgical techniques such as explorative laparotomy . As a basic principle, the simplest, cheapest test should be chosen hoping that it will answer the clinical question. This necessitates knowledge of the potential complications and diagnostic limitations of the various methods. For example, in a patient pr esenting with the clinical features of biliary colic, an ultrasound examination alone may give enough informa tion to enable appropriate surgical management. In more com plex cases, it may be more e ffi cient to opt for a single, more expensive investigation, such as CT , rather than embarking on multiple simpler and cheaper investigations that may not yield the answer. The choice of technique is often dictated by equipment availability , expertise and cost, as well as the clinical presentation. However, it must be emphasised that, not infre quently , the most valuable investigation is prior imaging; this not only reduces the cost and the amount of radiation a patient receives but v ery often improves patient care. Christian Johann Doppler , 1803–1853, Professor of Experimental Physics, Vienna, Austria, enunciated the ‘Doppler principle’ in 1842.

The principles of different imaging techniques and • their advantages and disadvantages in different clinical scenarios The role of imaging in directing treatment in various • surgical scenarios

Introduction

Trauma remains a major cause of mortality and morbidity in - all age groups. Presented with a multiply injured patient, rapid and e ff ective investigation and treatment are required to maxi - mise the chances of survival and to reduce morbidity . Imaging - plays a major role in this assessment and in guiding treatment. As with the clinical assessment, imaging is carried out according to the principles of primary and secondary surveys, identifying major life-threa tening injuries of the airway , respiratory system

(c) Figure 8.26 (a) The plain /f_i lms of this 13-year-old are close to normal. On close inspection, there is a /f_i ne periosteal reaction on the /f_i bula. (b) The cor

onal T1-weighted magnetic resonance image shows little more, but (c) the coronal fast short tau inversion recovery (STIR) images and (d) axial T2 fast spin echo with fat suppression show the oedema in bone as white and the extensive periosteal /f_l uid with soft-tissue in /f_l ammation. The diagnosis is acute osteomyelitis.

consuming assessment of other injures. At no point should imaging delay the treatment of immediately life-threatening injuries. As in other settings, the quickest and least invasive examinations should be performed first. A radiologist present in the trauma room at the time of patient assessment is able to evaluate the radiographs rapidly , relay this information back to the team and guide further imaging, which may include further plain films, CT , ultrasound and MRI.