ABSTRACT
The study was carried out in three government hospitals in Enugu metropolis. It was carried out to assess the level of awareness and attitude of emergency physicians towards the use of CT in patients with head injury. Questionnaire was the major instrument for data collection. The study sought to assess the reasons for the non regular request of CT scan for patients with head injury in view of the low diagnostic yield of skull x-ray traditionally requested for such cases. The result of the study showed that most of the emergency physicians are aware of the usefulness of CT in the examination of patients presenting with head injury, but the non availability of the CT imaging equipment greatly affected the rate of request for the examination thus has affected their attitude towards the use of this imaging modality in the examination of this category of patients in need of it. The cost of the examination appeared prohibitive to the patients. Majority of the emergency physicians strongly advocated the intervention of government towards availability and reduction in cost for effective health care delivery. However, some of the emergency physicians need to be informed about the high radiation dose associated with CT examination to reduce over request for the examination
LIST OF TABLES
Table i: physical characteristics of participants
Table ii: comparison between hospital of practice and continual use of CT as an imaging modality.
Table iii: comparison between hospital of employment and how often participants refer their patients with head injury for CT scan.
Table iv: comparison between hospital of practice and the discussion of CT examination with patients before requesting it to be done.
Table v: comparison between hospital of practice and if head injured patients should undergo both imaging modalities.
Table vi: comparison of years of practice and reference of patients for more of skull x-ray than CT scan.
TABLE OF CONTENTS
Title page…………………………………………………...………………………i
Approval page……………………………………………...……………….……...ii
Certification page……………………………………………………………..…...iii
Dedication.............................................…....iv
Acknowledgement……………………………………………………………..….v
Abstract……………………………………………………………………….….vi
List of tables……………………………………………………………………..vii
Table of contents………………………………………………………………..viii
CHAPTER ONE: INTRODUCTION
1.1Background of study…………………………………………………………….1
1.2 Statement of problems……………………………………………………….....4
1.3 Objectives of study……..………….……………………………………….…..4
1.4 Significance of study………………...……………………………………...….4
1.5 Scope of the study……………………………………...…………………..…...5
1.6 Literature of study………………………………………...……………..……..5
CHAPTER TWO: THEORITICAL BACKGROUND
2.1 Skull x-ray……………………………………………………………….……10
2.1.1 Reasons why skull x-ray is performed………………………………...……12
2.1.2 Risks of the procedure……………..…………………………………..……12
2.1.3 Before the procedure…………………………………………………..……13
2.1.4 During the procedure…… ……..………………………………………...…14
2.1.5 After the procedure………………………………………………………….15
2.2 computed tomography………………………………………………………...16
2.2.1 Procedure undertaken during CT………………………………….…….16
2.2.2 Risks associated with CT scan………………………………….…………17
2.2.3 Total or whole body CT……...……………………………………………17
2.2.4 Basic Principles of CT……………………………………………………..18
2.2.5 Historical Developments…………………………………………………..20
2.3 generations of ct……………………………………………………………...21
2.3.1 First-Generation CT Scanners………………………………………………21
2.3.2 Second-Generation CT Scanners…………………………………………23
2.3.3 Third-Generation CT Scanners…………………………………………..23
2.3.4 Fourth-Generation CT Scanners…………………………………………24
2.3.5 Fifth -Generation CT Scanners…………………………………………..26
2.3.6 Principles of Helical CT Scanners………………………………………..26
2.3.6.1 Slip-Ring Technology……...…………………………………………….27
2.3.6.2 High-Power X-ray Tubes………………………………….…………….27
2.3.6.3 Interpolation Algorithms……………………………….……………….28
2.3.7 Capabilities of Single-Row Detector Helical CT…………………………30
2.3.8 Multiple-Row Detector Helical CT……………………………………….30
2.3.9 Helical Pitch………………………………………………………………..32
2.3.10 Advantages of multiple-row detector helical CT……………………….32
2.3.11 Future Directions…………………………………………………………33
CHAPTER THREE: RESEARCH METHODOLOGY
3.1 Research design……………………….……………………………………..35
3.2 Target population……………………………………………………………35
3.3 Instrument for data collection…...………………………………………….36
3.4 Method of data collection……………………………………………………36
CHAPTER FOUR
4.1 Data presentation and analysis ………….……..….…………..……………..37
CHAPTER FIVE: DISCUSSION
5.1 Demographic findings……………………………………………………….49
5.2 Awareness level on CT imaging modality……………………………….…49
5.3 Attitude towards the use of CT……………………………….………….…50
5.4 Conclusion………………………………………………………………..…..51
5.5 Recommendation………...…………………………………………………..52
5.6 Limitations of the study…..………………………….……….……………..54
5.7 Areas for further study……………...………………………………………54
REFERENCES
INTRODUCTION
Head injury is a non degenerative, non congenital insult to the brain from external mechanical forces, possibly leading to permanent or temporary impairment of cognitive, physical, and psychosocial functions with an associated diminished or altered state of consciousness. Head injury can also be defined as any alteration in mental or physical functioning related to a blow to the head and often may or may not be associated with brain injury1. It can also be defined as any trauma that leads to injury to the scalp, skull, or brain. It can range from a minor bump on the skull to serious brain injury. It may result in contusion or- if the blood vessels in the head are torn- to a hematoma1. The features of an injured head can be seen by undergoing radiological examinations such as skull x-ray and computed tomography examination.
Historically, skull x-ray examinations have been used as a standard radiological procedure in the evaluation of patients with head injury. The conventional skull x-ray is ordered to detect and evaluate abnormalities of the head. Skull radiography is useful for imaging of calvarial fractures, penetrating injuries, and radiopaque foreign bodies. They provide strong evidence of skull fracture and in some cases provide clues about abnormal intracranial conditions. They have held a traditional place in the evaluation of patients with head injury or sudden onset of unconsciousness or coma2.
Over time, the procedure has come to be viewed as unnecessary to the provision of quality care, and it has been claimed that many such examinations are ordered by emergency room physicians for medico-legal reasons or because the patient or patients family requests it, and not because the physician sees the examination as contributing greatly to his or her information. The yield of abnormal findings in skull x-rays ordered in this way is low2. The skull x-ray has been criticized as an overused and not very valuable radiological procedure due to the drawbacks it was seen to have. This criticism has stemmed from;
1. studies demonstrating the low yield of positive skull x-rays and low sensitivity of the skull x-ray in detecting clinically important intracranial abnormalities such as subdural hematoma and cortical atrophy,
2. the general unimportance of detecting a fracture in the absence of any clinical evidence of intracranial damage, and
3. The arrival of a noninvasive diagnostic imaging technology that offers vastly superior information on intracranial disease and injury, namely, the computed tomography scanner3.
Computed Tomography(CT) scanning sometimes called Computed Axial Tomography(CAT) scanning is a noninvasive medical test that helps physicians diagnose and treat medical conditions4. Computed tomography can be defined as a form of radiological examination in which the x-ray source and detector(CT scanner) rotate around the object to be scanned and the information obtained can be used to produce cross-sectional images by a computer(a CT scan). CT scanning combines special x-ray equipment with sophisticated computers to produce multiple images or pictures of the inside of the body. These cross-sectional images of the area being studied can then be examined on a computer monitor, printed or transferred to a CD5.
The advent of computerized tomography (CT) has revolutionized the assessment of the brain6 which is fast growing in the radiology department and has gradually taken over other imaging modalities in the treatment of head injury presented by patients. Its application in the management of head injury is well documented7. Patterns of CT findings show the different tomographic pattern as seen in the various slices.
Computed tomography plays a very important role in the management of the patients with head injury by providing non-invasive and accurate means of demonstrating both the immediate and delayed features of head injury. It offers better evaluation of the emergency nature of the patient’s condition and enhances resolution in demonstrating intracranial haemorrhage and cerebral infarction8.
Other advantages of CT for evaluation of the head-injured patient include its sensitivity for demonstrating mass effect, ventricular size and configuration, bone injuries, and acute hemorrhage regardless of location (i.e., parenchymal, subarachnoid, subdural, or epidural spaces), widespread availability, rapidity of scanning, and compatibility with other medical and life support devices. Its limitations include insensitivity in detecting small and predominantly nonhemorrhagic lesions associated with trauma such as contusion, particularly when adjacent to bony surfaces (e.g., frontal lobes adjacent to the orbital roof, anterior temporal lobe adjacent to the greater sphenoid wing). Likewise, Diffuse Axonal Injuries (DAIs) that result in small focal lesions throughout the cerebral hemispheres, corpus callosum, and upper brainstem and cerebellum often go undetected on CT. CT is also relatively insensitive for detecting increased intracranial pressure or cerebral edema and for early demonstration of Hypoxic-Ischemic Encephalopathy (HIE) that may accompany moderate or severe head injury. Potential risks of unnecessary exposure to ionizing radiation warrant judicious patient selection for CT scanning as well as radiation dose management.
This study therefore intends to assess the level of awareness and attitude of emergency physicians towards the use of CT in patients with head injury in Enugu metropolis.