Guide to Medical Electronics and Applications: Table of Contents and Overview

1. Introduction

2. Anatomy and Physiology

• Introduction
• Anatomical terminology
• Structural level of the human body
• Muscular system
• Skeletal system
• Nervous system
• Cardio-vascular system
• Respiratory system

3. Physics

• The nature of ionizing radiation
• Physics of radiation absorption, types of collision
• Radiation measurement and dosimetry
• Outline of the application of radiation in medicine--radiology, radiotherapy
• Physics of NMR
• Ultrasound
• Physics of ultrasound
• The Doppler effect
• Generation and detection of ultrasound

4. Physiological Instrumentation

• Introduction
• Measurement systems
• Transducers
• Biopotentials
• Blood pressure measurement

5. Imaging Fundamentals and Math

• Purpose of imaging
• Mathematical background
• Imaging theory
• Image processing

6. Imaging Technology

• Projection X radiography
• Computerized tomography
• Gamma camera
• Nuclear magnetic resonance imaging
• Ultrasound imaging
• Doppler ultrasound

7. Computing

• Classification of computers
• Outline of computer architecture
• Data acquisition
• Computer networks
• Databases
• Clinical expert systems
• Privacy, data protection and security
• Practical considerations

8. Hospital Safety

• Electrical safety
• Radiation hazards

Overview of this Guide

This guide is intended as an introductory text for Engineering and Applied Science Students to the Medical Applications of Electronics. A course has been offered for many years in a UK university in this arena. A new group, the Medical Systems Engineering Research Unit, was established following the reorganization of the College. Restructuring and review of our course material and placing the responsibility for teaching this course within the new group led to a search for new material. Whilst we found a number of available texts which were suitable for aspects of our new course, we found a need for a text which would encompass a wide scope of material which would be of benefit to students completing their degree programs and contemplating professional involvement in Medical Electronics.

Medical Electronics is a broad field. Whilst much of the material which an entrant to medical applications must acquire is the conventional basis of electronics covered by any student of electronics, there are areas of special emphasis. Many of these arise from areas which are increasingly inaccessible to students who necessarily specialize at an early stage in their education.

The need for diversity is reflected in the educational background and experience of the authors. Amongst us is a Medical Practitioner who is also a Mechanical Engineer, a Physicist who now works as a Software Engineer, an Electronics Engineer who made the same move, and another Electronics Engineer with some experimental experience in Orthopedics.

The material which this guide attempts to cover starts with an Introduction which hopefully provides some perspective in the subject area. The following section provides an introduction to human anatomy and physiology. The approach taken here is necessarily simplified: it is our intention to provide an adequate grounding for the material in the following sections both in its basic science and the nomenclature which may be unfamiliar to readers with only elementary biological knowledge.

Section 3 describes the Physics employed in diagnostic techniques. This encompasses basic radiation physics, magnetic resonance and the nature and generation of ultrasound.

Section 4 discusses the form of some of the basic electronic elements used in Medical Applications. We describe the specialized techniques which are employed and characterize the signals which are likely to be encountered. Special emphasis is attached to issues of patient safety, although these are covered in greater depth in Section 8.

The mathematical background for image processing is covered in Section 5. This material has been separated from our description of representative diagnostic imaging technologies presented in Section 6. This latter Section includes material supplied by Toshiba Medical Systems, whose assistance we gratefully acknowledge.

Section 7 contains background material concerning computers, their architecture, application to data acquisition and connection to networks. It also covers some aspects of the application of Databases and Expert Systems to Medicine which have long been expected to play central roles in patient care. The increasing capacity of systems together with their continuing cost reductions mean that their introduction is now becoming a reality. The introductory parts of this Section will be familiar to many engineers: we have included it to ensure that this guide shall have a wide enough sphere of interest.

Finally, Section 8 examines aspects of patient safety which are of concern to engineers. This area is a particularly difficult one in which to be specific as it is intimately entwined with changing legislation. We seek to present here principles and what we believe to be good practice: these must form the basis of any competent engineer's activity.

This guide has been some time in gestation. We wish to acknowledge the patience of our families, without whom no doubt the task would have been completed more quickly. We have been assisted too in no small measure by students and researchers in the Medical Systems Engineering Research Unit who have provided both constructive criticisms and help by checking manuscripts.