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Diagnostic imaging in undergraduate medical education: an expanding role
Clinical Radiology (2005) 60, 742–745
REVIEW
Diagnostic imaging in undergraduate medical education: an expanding role K.A. Miles* Brighton and Sussex Medical School, University of Sussex, Brighton, UK Received 8 December 2004; received in revised form 31 January 2005; accepted 8 February 2005
KEYWORDS Anatomy; Education; Computers; PACS; Dissection
Radiologists have been involved in anatomy instruction for medical students for decades. However, recent technical advances in radiology, such as multiplanar imaging, “virtual endoscopy”, functional and molecular imaging, and spectroscopy, offer new ways in which to use imaging for teaching basic sciences to medical students. The broad dissemination of picture archiving and communications systems is making such images readily available to medical schools, providing new opportunities for the incorporation of diagnostic imaging into the undergraduate medical curriculum. Current reforms in the medical curriculum and the establishment of new medical schools in the UK further underline the prospects for an expanding role for imaging in medical education. This article reviews the methods by which diagnostic imaging can be used to support the learning of anatomy and other basic sciences. Q 2005 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.
Introduction Significant advances in diagnostic imaging in recent years have produced new ways in which to depict the structure and function of the human body, including functional and molecular imaging and magnetic resonance spectroscopy. In addition, improvements in information technology have increased the ways in which diagnostic images can be displayed, stored and transferred. Three-dimensional (3D) reconstructions and “virtual endoscopy” can now be performed in seconds, and picture archiving and communication systems (PACS) allow transfer of diagnostic images to multiple sites, not only for clinical but also for educational purposes. Furthermore, although the importance of anatomy in the undergraduate medical curriculum remains undisputed, there is currently debate concerning methods for delivering anatomy teaching. In * Guarantor and correspondent: K.A. Miles, Brighton and Sussex Medical School, University of Sussex, Falmer, Brighton BN1 9PX, UK. Tel.: C44 1273 877574; fax: C44 1273 877576. E-mail address: [email protected].
particular, the use of cadavers for dissection has been identified by some as expensive, time-consuming and potentially hazardous.1 Indeed, some new medical schools have discarded dissection altogether, seeking alternative approaches to anatomy teaching, including the use of diagnostic images.2–4 Although radiologists have been involved in anatomy instruction for medical students for decades,5 the above factors have led to a renewed interest in the place of diagnostic imaging in undergraduate medical education. The purpose of this article is to review the deployment of diagnostic imaging in the learning of anatomy and other basic sciences, highlighting new opportunities and discussing the relationship to cadaveric dissection.
The importance of anatomical knowledge The basic sciences of anatomy, physiology and biochemistry have underpinned the teaching of
0009-9260/$ - see front matter Q 2005 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved. doi:10.1016/j.crad.2005.02.011
Diagnostic imaging in undergraduate medical education
medicine for decades. In the 1879 Hunterian oration, G. M. Humphry stated that: The knowledge of the facts of anatomy [is] essential to the practice of surgery, and to an appreciation of physiology; and the correct learning of them promotes the habit of attention, and of accuracy which is the associate of attention. Still it may be questioned whether.the result is proportionate to the time and labour expended. Certainly there is no subject which men exhibit so much proneness to forget. The knowledge, painfully acquired, is strainingly held and cheerfully let go. As his oration predated Roentgen’s discovery of X-rays by some 16 years, Humphry would not have been able to consider the potential for medical imaging to enhance the learning of anatomy. The explosion in information technology has increased this learning potential even further, through the development of digital radiography and advanced imaging techniques such as ultrasound (US), computed tomography (CT) and magnetic resonance imaging (MRI). As well as reiterating the important role of anatomy in the medical curriculum today, the General Medical Council’s Tomorrow’s doctors6 calls for medical schools to take advantage of new technologies to deliver teaching. The use of medical imaging to support the learning of anatomy is one example of how these two requirements can be met at the same time.
Opportunities for using diagnostic imaging in undergraduate medical education The system for image-based learning developed at the Brighton & Sussex Medical School encompasses many of the learning opportunities offered by information technology. A computerized medical imaging database has been established with software developed from PACS. Digital links from imaging devices at the local hospital allow radiologists and others to identify images suitable for education and add them to the database. Appropriate image formats include individual frames, 3D data sets and time series; 3D data sets, for example from CT, have allowed virtual dissection in which a body region is re-sliced in multiple planes. Time series are used to display organ motion, for instance the beating heart, or to demonstrate how the internal body distributions of radioactive tracers or contrast agents change over time, for example
743
when filtered at the glomerulus and subsequently passed down the renal tract. In this way, anatomical structure is directly correlated with physiological function. Newer molecular imaging techniques illustrate aspects of molecular biology, such as positron emission tomography (PET) images demonstrating that tumours exhibit increased glucose metabolism. A learning environment in which the whole class accesses the image database simultaneously creates opportunities for interactive learning (Fig. 1). The class is asked to identify structures on an image or answer multiple-choice questions, and the students’ responses are compiled and displayed as a scatter plot or histogram, thereby providing instantaneous yet anonymous feed back (Fig. 2). An additional benefit gained from PACS is that students at an early stage become familiar with technology they will need to use in their future professional lives as the National Programme for Information Technology for the NHS is implemented. Although the main focus in the early years of medical education is on normal anatomy, the use of abnormal radiographs need not be excluded at this stage, because disease processes often reveal anatomical features not visible on normal studies. For example, chest and abdominal radiographs from an individual with a perforated abdominal viscus and free intraperitoneal gas demonstrate the thickness of the bowel wall or diaphragm; many students are surprised by its thinness. Similarly, pathological calcification can disclose the size and position of the adrenal glands, which are normally invisible on plain radiographs. In this way, students gain immediate awareness of the clinical relevance
Figure 1 A computer suite such provides a learning environment in which a whole class of students can assess diagnostic images simultaneously and take part in interactive teaching sessions.
744
K.A. Miles
favourable responses from medical students to the use of US as an educational tool.7,8 At our institution, US is used to reinforce students’ knowledge of surface anatomy by visualizing the liver, spleen, gall bladder and kidneys after students have marked the locations of these organs on the skin of a colleague. Although more expensive, MRI offers even greater opportunities to demonstrate not only anatomy but also physiology and biochemistry. Functional MRI can demonstrate regional brain activation during a variety of cognitive tasks, and MRI spectroscopy can display the relative concentrations of biochemical molecules in a range of tissues. The use of imaging examinations in this way does create ethical issues arising from the possibility of finding incidental pathology. These issues already exist within medical education, for instance when students test their own urine for glucose, and are essentially no different when using imaging tests. However, obtaining written informed consent may be advisable, and it should also be made clear that students should not see imaging tests performed for educational purposes as an alternative to seeking medical attention through normal channels.
Relationship of imaging to cadaveric dissection Figure 2 Sample responses from a group of lay visitors to the Brighton and Sussex Medical School open day who were asked to “click on the fourth metacarpal on this Xray that Wilhelm Roentgen, the discoverer of X-rays, took of his wife’s hand”. Each green cross represents a response from an individual participant (Software developed by Cambridge Computed Imaging Ltd, Bourne, UK).
of anatomical knowledge while also gaining familiarity with radiological signs. Much can be learned from diagnostic images included in clinically indicated examinations of patients, and additional opportunities are offered by imaging examinations of volunteers purely for educational purposes. Clearly, the need to avoid ionizing radiation restricts such examinations to methods such as US and MRI. Additionally, high demands upon clinical imaging departments may require medical schools to obtain their own imaging devices in order to realize these opportunities. US systems are relatively cheap, and previous studies describe
With such educational possibilities offered by the use of medical imaging, it could be asked whether there remains any need to use cadaveric dissection for teaching anatomy. However, many teachers consider that dissection offers benefits that cannot be achieved with anatomical models or medical images.1–3 Some structures may be hard to display adequately with current imaging techniques, for instance peripheral nerves with complex courses. Furthermore, dissection confers an appreciation of the “feel” of tissues and organs, and provides an opportunity for students to confront issues surrounding trauma and death in ways that medical images cannot. There are few data comparing the effectiveness of imaging and dissection as alternative tools for learning anatomy. On the other hand, studies have suggested a synergistic relationship betweens these modes of teaching. Radiography of cadavers for teaching purposes was proposed more than 20 years ago,9 and combining medical imaging with cadaveric dissection has been reported to generate a high level of student interest in gross anatomy10 that has
Diagnostic imaging in undergraduate medical education
been confirmed by student feedback at our institution. The combination has been shown to improve students’ ability to identify anatomical structures and is associated with high levels of long-term knowledge retention.11,12 The availability of medical images in the dissection room has been shown to enhance the independence and proficiency of students and improve the efficiency of their dissection time.13 Provision to students of a set of crosssectional images (CT or MRI) for the individual cadaver they are dissecting has great potential to increase the benefits of this combined learning approach even further. Although more research is needed in this area, current evidence suggests that imaging and cadaveric dissection may be complementary rather than competitive tools for learning anatomy.
Conclusions The appearances of Humphry’s ligament, the anterior branch of the meniscofemoral ligament, were reported on MRI of the knee a little more than one century after his Hunterian oration. Although Humphry’s 19th century observations may resonate with many of us today, the increasing sophistication with which radiology can depict the human body, combined with electronic availability of the resulting images, means that radiologists can play a significant role in making knowledge of anatomy less laborious for tomorrow’s doctors to acquire and less difficult to retain.
745
References 1. Aziz AA, McKenzie JC, Wilson JS, Cowie RJ, Sylvanus AA, Dunn BK. The human cadaver in the age of biomedical informatics. Anat Rec 2002;269:20—32. 2. Howe A, Campion P, Searle J, Smith H. New perspectives— approaches to medical education at four new UK medical schools. BMJ 2004;329:327—31. 3. Parker LM. What’s wrong with the dead body? Use of the human cadaver in medical education Med J Aust 2002;176: 74—6. 4. McLachlan JC, Bligh J, Bradley P, Searle J. Teaching anatomy without cadavers. Med Educ 2004;38:418—24. 5. Bassett LW, Squire LF. Anatomy instruction by radiologists. Invest Radiol 1985;20:1008—10. 6. General Medical Council. Tomorrow’s doctors: recommendations on undergraduate medical education. 2nd ed. London, UK: General Medical Council; 2003. 7. Heilo A, Hansen AB, Holck P, Laerum F. Ultrasound ‘electronic vivisection’ in the teaching of human anatomy for medical students. Eur J Ultrasound 1997;5:203—7. 8. Shapiro RS, Ko PP, Jacobson S. A pilot project to study the use of ultrasonography for teaching physical examination to medical students. Comput Biol Med 2002;32:403—9. 9. McNiesh LM, Madewell JE, Allman RM. Cadaver radiography in the teaching of gross anatomy. Radiology 1983;148:73—4. 10. Pabst R, Westermann J, Lippert H. Integration of clinical problems in teaching gross anatomy: living anatomy, X-ray anatomy, patient presentations, and films depicting clinical problems. Anat Rec 1986;215:92—4. 11. Erkonen WE, Albanese MA, Smith WL, Pantazis NJ. Gross anatomy instruction with diagnostic images. Invest Radiol 1990;25:292—4. 12. Erkonen WE, Albanese MA, Smith WL, Pantazis NJ. Effectiveness of teaching radiologic image interpretation in gross anatomy. A long-term follow-up. Invest Radiol 1992;27: 2646. 13. Reeves RE, Aschenbrenner JE, Wordinger RJ, Roque RS, Sheedlo HJ. Improved dissection efficiency in the human gross anatomy laboratory by the integration of computers and modern technology. Clin Anat 2004;17:337—44.
REVIEW
Diagnostic imaging in undergraduate medical education: an expanding role K.A. Miles* Brighton and Sussex Medical School, University of Sussex, Brighton, UK Received 8 December 2004; received in revised form 31 January 2005; accepted 8 February 2005
KEYWORDS Anatomy; Education; Computers; PACS; Dissection
Radiologists have been involved in anatomy instruction for medical students for decades. However, recent technical advances in radiology, such as multiplanar imaging, “virtual endoscopy”, functional and molecular imaging, and spectroscopy, offer new ways in which to use imaging for teaching basic sciences to medical students. The broad dissemination of picture archiving and communications systems is making such images readily available to medical schools, providing new opportunities for the incorporation of diagnostic imaging into the undergraduate medical curriculum. Current reforms in the medical curriculum and the establishment of new medical schools in the UK further underline the prospects for an expanding role for imaging in medical education. This article reviews the methods by which diagnostic imaging can be used to support the learning of anatomy and other basic sciences. Q 2005 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.
Introduction Significant advances in diagnostic imaging in recent years have produced new ways in which to depict the structure and function of the human body, including functional and molecular imaging and magnetic resonance spectroscopy. In addition, improvements in information technology have increased the ways in which diagnostic images can be displayed, stored and transferred. Three-dimensional (3D) reconstructions and “virtual endoscopy” can now be performed in seconds, and picture archiving and communication systems (PACS) allow transfer of diagnostic images to multiple sites, not only for clinical but also for educational purposes. Furthermore, although the importance of anatomy in the undergraduate medical curriculum remains undisputed, there is currently debate concerning methods for delivering anatomy teaching. In * Guarantor and correspondent: K.A. Miles, Brighton and Sussex Medical School, University of Sussex, Falmer, Brighton BN1 9PX, UK. Tel.: C44 1273 877574; fax: C44 1273 877576. E-mail address: [email protected].
particular, the use of cadavers for dissection has been identified by some as expensive, time-consuming and potentially hazardous.1 Indeed, some new medical schools have discarded dissection altogether, seeking alternative approaches to anatomy teaching, including the use of diagnostic images.2–4 Although radiologists have been involved in anatomy instruction for medical students for decades,5 the above factors have led to a renewed interest in the place of diagnostic imaging in undergraduate medical education. The purpose of this article is to review the deployment of diagnostic imaging in the learning of anatomy and other basic sciences, highlighting new opportunities and discussing the relationship to cadaveric dissection.
The importance of anatomical knowledge The basic sciences of anatomy, physiology and biochemistry have underpinned the teaching of
0009-9260/$ - see front matter Q 2005 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved. doi:10.1016/j.crad.2005.02.011
Diagnostic imaging in undergraduate medical education
medicine for decades. In the 1879 Hunterian oration, G. M. Humphry stated that: The knowledge of the facts of anatomy [is] essential to the practice of surgery, and to an appreciation of physiology; and the correct learning of them promotes the habit of attention, and of accuracy which is the associate of attention. Still it may be questioned whether.the result is proportionate to the time and labour expended. Certainly there is no subject which men exhibit so much proneness to forget. The knowledge, painfully acquired, is strainingly held and cheerfully let go. As his oration predated Roentgen’s discovery of X-rays by some 16 years, Humphry would not have been able to consider the potential for medical imaging to enhance the learning of anatomy. The explosion in information technology has increased this learning potential even further, through the development of digital radiography and advanced imaging techniques such as ultrasound (US), computed tomography (CT) and magnetic resonance imaging (MRI). As well as reiterating the important role of anatomy in the medical curriculum today, the General Medical Council’s Tomorrow’s doctors6 calls for medical schools to take advantage of new technologies to deliver teaching. The use of medical imaging to support the learning of anatomy is one example of how these two requirements can be met at the same time.
Opportunities for using diagnostic imaging in undergraduate medical education The system for image-based learning developed at the Brighton & Sussex Medical School encompasses many of the learning opportunities offered by information technology. A computerized medical imaging database has been established with software developed from PACS. Digital links from imaging devices at the local hospital allow radiologists and others to identify images suitable for education and add them to the database. Appropriate image formats include individual frames, 3D data sets and time series; 3D data sets, for example from CT, have allowed virtual dissection in which a body region is re-sliced in multiple planes. Time series are used to display organ motion, for instance the beating heart, or to demonstrate how the internal body distributions of radioactive tracers or contrast agents change over time, for example
743
when filtered at the glomerulus and subsequently passed down the renal tract. In this way, anatomical structure is directly correlated with physiological function. Newer molecular imaging techniques illustrate aspects of molecular biology, such as positron emission tomography (PET) images demonstrating that tumours exhibit increased glucose metabolism. A learning environment in which the whole class accesses the image database simultaneously creates opportunities for interactive learning (Fig. 1). The class is asked to identify structures on an image or answer multiple-choice questions, and the students’ responses are compiled and displayed as a scatter plot or histogram, thereby providing instantaneous yet anonymous feed back (Fig. 2). An additional benefit gained from PACS is that students at an early stage become familiar with technology they will need to use in their future professional lives as the National Programme for Information Technology for the NHS is implemented. Although the main focus in the early years of medical education is on normal anatomy, the use of abnormal radiographs need not be excluded at this stage, because disease processes often reveal anatomical features not visible on normal studies. For example, chest and abdominal radiographs from an individual with a perforated abdominal viscus and free intraperitoneal gas demonstrate the thickness of the bowel wall or diaphragm; many students are surprised by its thinness. Similarly, pathological calcification can disclose the size and position of the adrenal glands, which are normally invisible on plain radiographs. In this way, students gain immediate awareness of the clinical relevance
Figure 1 A computer suite such provides a learning environment in which a whole class of students can assess diagnostic images simultaneously and take part in interactive teaching sessions.
744
K.A. Miles
favourable responses from medical students to the use of US as an educational tool.7,8 At our institution, US is used to reinforce students’ knowledge of surface anatomy by visualizing the liver, spleen, gall bladder and kidneys after students have marked the locations of these organs on the skin of a colleague. Although more expensive, MRI offers even greater opportunities to demonstrate not only anatomy but also physiology and biochemistry. Functional MRI can demonstrate regional brain activation during a variety of cognitive tasks, and MRI spectroscopy can display the relative concentrations of biochemical molecules in a range of tissues. The use of imaging examinations in this way does create ethical issues arising from the possibility of finding incidental pathology. These issues already exist within medical education, for instance when students test their own urine for glucose, and are essentially no different when using imaging tests. However, obtaining written informed consent may be advisable, and it should also be made clear that students should not see imaging tests performed for educational purposes as an alternative to seeking medical attention through normal channels.
Relationship of imaging to cadaveric dissection Figure 2 Sample responses from a group of lay visitors to the Brighton and Sussex Medical School open day who were asked to “click on the fourth metacarpal on this Xray that Wilhelm Roentgen, the discoverer of X-rays, took of his wife’s hand”. Each green cross represents a response from an individual participant (Software developed by Cambridge Computed Imaging Ltd, Bourne, UK).
of anatomical knowledge while also gaining familiarity with radiological signs. Much can be learned from diagnostic images included in clinically indicated examinations of patients, and additional opportunities are offered by imaging examinations of volunteers purely for educational purposes. Clearly, the need to avoid ionizing radiation restricts such examinations to methods such as US and MRI. Additionally, high demands upon clinical imaging departments may require medical schools to obtain their own imaging devices in order to realize these opportunities. US systems are relatively cheap, and previous studies describe
With such educational possibilities offered by the use of medical imaging, it could be asked whether there remains any need to use cadaveric dissection for teaching anatomy. However, many teachers consider that dissection offers benefits that cannot be achieved with anatomical models or medical images.1–3 Some structures may be hard to display adequately with current imaging techniques, for instance peripheral nerves with complex courses. Furthermore, dissection confers an appreciation of the “feel” of tissues and organs, and provides an opportunity for students to confront issues surrounding trauma and death in ways that medical images cannot. There are few data comparing the effectiveness of imaging and dissection as alternative tools for learning anatomy. On the other hand, studies have suggested a synergistic relationship betweens these modes of teaching. Radiography of cadavers for teaching purposes was proposed more than 20 years ago,9 and combining medical imaging with cadaveric dissection has been reported to generate a high level of student interest in gross anatomy10 that has
Diagnostic imaging in undergraduate medical education
been confirmed by student feedback at our institution. The combination has been shown to improve students’ ability to identify anatomical structures and is associated with high levels of long-term knowledge retention.11,12 The availability of medical images in the dissection room has been shown to enhance the independence and proficiency of students and improve the efficiency of their dissection time.13 Provision to students of a set of crosssectional images (CT or MRI) for the individual cadaver they are dissecting has great potential to increase the benefits of this combined learning approach even further. Although more research is needed in this area, current evidence suggests that imaging and cadaveric dissection may be complementary rather than competitive tools for learning anatomy.
Conclusions The appearances of Humphry’s ligament, the anterior branch of the meniscofemoral ligament, were reported on MRI of the knee a little more than one century after his Hunterian oration. Although Humphry’s 19th century observations may resonate with many of us today, the increasing sophistication with which radiology can depict the human body, combined with electronic availability of the resulting images, means that radiologists can play a significant role in making knowledge of anatomy less laborious for tomorrow’s doctors to acquire and less difficult to retain.
745
References 1. Aziz AA, McKenzie JC, Wilson JS, Cowie RJ, Sylvanus AA, Dunn BK. The human cadaver in the age of biomedical informatics. Anat Rec 2002;269:20—32. 2. Howe A, Campion P, Searle J, Smith H. New perspectives— approaches to medical education at four new UK medical schools. BMJ 2004;329:327—31. 3. Parker LM. What’s wrong with the dead body? Use of the human cadaver in medical education Med J Aust 2002;176: 74—6. 4. McLachlan JC, Bligh J, Bradley P, Searle J. Teaching anatomy without cadavers. Med Educ 2004;38:418—24. 5. Bassett LW, Squire LF. Anatomy instruction by radiologists. Invest Radiol 1985;20:1008—10. 6. General Medical Council. Tomorrow’s doctors: recommendations on undergraduate medical education. 2nd ed. London, UK: General Medical Council; 2003. 7. Heilo A, Hansen AB, Holck P, Laerum F. Ultrasound ‘electronic vivisection’ in the teaching of human anatomy for medical students. Eur J Ultrasound 1997;5:203—7. 8. Shapiro RS, Ko PP, Jacobson S. A pilot project to study the use of ultrasonography for teaching physical examination to medical students. Comput Biol Med 2002;32:403—9. 9. McNiesh LM, Madewell JE, Allman RM. Cadaver radiography in the teaching of gross anatomy. Radiology 1983;148:73—4. 10. Pabst R, Westermann J, Lippert H. Integration of clinical problems in teaching gross anatomy: living anatomy, X-ray anatomy, patient presentations, and films depicting clinical problems. Anat Rec 1986;215:92—4. 11. Erkonen WE, Albanese MA, Smith WL, Pantazis NJ. Gross anatomy instruction with diagnostic images. Invest Radiol 1990;25:292—4. 12. Erkonen WE, Albanese MA, Smith WL, Pantazis NJ. Effectiveness of teaching radiologic image interpretation in gross anatomy. A long-term follow-up. Invest Radiol 1992;27: 2646. 13. Reeves RE, Aschenbrenner JE, Wordinger RJ, Roque RS, Sheedlo HJ. Improved dissection efficiency in the human gross anatomy laboratory by the integration of computers and modern technology. Clin Anat 2004;17:337—44.