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Nail-Tutor: an image-based personal computer program that teaches the anatomy, patterns of pathology, and disorders of the nails.

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Nail-TutorTM: an image-based personal computer program that teaches the anatomy, patterns of pathology, and disorders of the nails.
Philip Fleckman, M.D., Jennifer Lee, Michael L. Astion M.D. Ph.D.
Dermatology Online Journal 3(2): 2


Despite the clinical relevance of the nails, the interpretation of the appearance of the nails is often neglected by clinicians and in medical training programs. To help overcome this we developed Nail-TutorTM, a personal computer program based on approximately 150 images that systematically teaches the anatomy, patterns of pathology, and diseases of the nails and tests the user's understanding of the material in the program. Nail-TutorTM is intended for medical students, residents, other healthcare trainees, general practitioners, and dermatologists and requires approximately 3 hours to use. The program has a number of advantages over textbook-based instruction and supervised instruction. It does not require an instructor or textbook. In addition it uses animation to show an important anatomic relationship, graphic overlays to unambigously point out key features of images, it can show key images side by side for comparison, and an examination to evaluate learning objectives. The program can be used as a stand-alone teaching module, a supplement to traditional instruction, a source for continuing education, or as a reference.


The examination of the nails is often neglected by clinicians, even though the nails can provide valuable insight into dermatologic and systemic diseases. Overlooking nail disorders can have dramatic clinical consequences, for example missing malignant or potentially malignant pigmented nail lesions. In addition, nail disorders are a common patient complaint in both dermatologic and general medical practices, and many of these nail disorders are treatable. Finally, the language used to properly describe nail disorders is not well known among general practitioners, making for awkward, imprecise communication between the generalist and the dermatologist when patients with nail disorders are discussed.

Despite the clinical relevance of the nails, nail anatomy, pathology and diseases are given inadequate attention in medical school and other health care training programs. The traditional approaches to teaching are lectures, supervised instruction at the bedside or in the clinic, and review of textbooks. Lectures on the nails are useful but they are either minimally employed or absent from medical training. Bedside or clinical teaching is not consistent from student to student. Textbook teaching can be very useful. However, it is often problematic because the image quality achievable in a book is quite variable, and it can be difficult to motivate residents, students, as well as fully-trained physicians to read books to systematically learn about the nails.

Our software development group at the University of Washington has been developing computer programs that help medical personnel learn a variety of image-based diagnostic tasks. Our previous work has focused on the most common image-based tests in the clinical laboratory and includes GramStain-Tutor (Cookson et al., 1994; Mandel et al 1996) which teaches the intepretation of direct Gram stains, Urinalysis-Tutor (Henderson et al, 1995) which teaches the microscopic examination of urine sediment, and many others (Astion et al., 1993, 1995; for review see Astion et al., 1996).

The computer program we describe here, Nail-TutorTM (Lippincot-Raven Publishers, Philadelphia, PA; Novartis Pharmaceuticals, East Hanover, NJ), represents an application of our underlying software engine to an important educational problem in dermatology. Nail-TutorTM is an image-based, personal computer program for medical doctors, medical students, and other health care trainees that uses about 150 images and illustrations to systematically teach the anatomy, pathologic patterns, and disorders of the nails. The educational objectives of Nail-TutorTM are that users who have completed the program should be able do the following: 1) describe with proper medical terminology the normal anatomy of the nail unit including its blood supply, 2) identify the parts of the history, physical exam, and laboratory exam that are most relevant to patients who have nail lesions, 3) use proper medical terminology to name and describe the most common patterns of nail unit pathology, and to state which part or parts of the nail unit (i.e., nail plate and matrix, nail bed, nail folds) is/are most likely to be involved for a particular pattern of pathology, 4) look at an image of diseased nails, identify the pattern of pathology present, and state the differential diagnosis for that pattern of pathology, 5) describe nail changes that can be classified as normal variants or normally associated with aging, 6) name the major acquired disorders and congenital disorders of the nails, 7) identify nail changes that may reflect underlying systemic disease, and 8) describe the typical patterns of pathology and other key clinical findings associated with the most common types of nail disorders.


Nail-TutorTM is written in Microsoft Visual Basic 3.0 (Microsoft Corp., Redmond, WA). The minimum hardware configuration to adequately display the program is an 80486 PC with 4MB RAM, equipped with 22 megabytes of hard disk space, a mouse, and a graphics adapter capable of displaying 256 colors at a screen resolution of 640 x 480 pixels. A screen resolution of 800 x 600 pixels is strongly recommended. High resolution digital images of normal and abnormal nails were obtained by using a Nikon LS 1000 scanner (Nikon Corp., Melville, NY) to digitize 2 x 2 slides from the collections of the authors and their colleagues. Some of these digital images were edited using Adobe Photoshop 3.0 (Adobe Systems, Mountain View, CA). Illustrations and animation were created with Caligari TrueSpace version 2.0 (Caligari Corp, Mountain View, CA).

An early version of Nail-TutorTM was reviewed by dermatologists, medical students and general internists from within and outside the University of Washington. These users provided detailed feedback that was used to complete the final version of the tutorial.

Program Description

Figure 1
Figure 1: Schematic of the Nail-Tutor Computer Program. More detail on the Acquired Disease section is shown in figure 2 (below).
Figure 2
Figure 2: Schematic of the Acquired Disease section of the tutorial.
Figure 3
Figure 3: The main menu screen of Nail-Tutor. The program is completely operated by making selections with the mouse.
Nail-TutorTM is based on images and illustrations that occur on almost all screens of the program. The program uses a simple interface that has been used for 5 years in our other tutorials, and which has received excellent reviews in surveys of users (Mandel et al., 1996). The entire program can be operated by single clicking on large buttons using the left mouse button. There is no typing, no use of pull down menus, no scroll bars, and no double clicking. Hypertext, in which underlined words can be clicked upon, is used to define approximately 50 key words.

Figure 4
Figure 4: A screen captured from the Introduction section of Nail-Tutor.TM
Nail-TutorTM is divided into the following sections: Introduction, Patterns of Nail Unit Pathology, Classification of Nail Disorders, Image Atlas, and the Final Exam. Schematics showing the contents of the program are shown in figures 1 and 2, and a screen from the program showing the main menu is shown in figure 3.
Figure 5
Figure 5: This screen from the Introduction section of Nail-Tutor shows the nail unit. The nail matrix is highlighted in white because the button labeled "Nail-Matrix" has been selected by the user.
The introduction teaches the anatomy and physiology of the normal nail unit and the approach to patients with nail disorders. The anatomy/physiology section shows the topography of the nail unit using an image of a finger nail with key features -such as the cuticle, nail folds, nail plate, and onychodermal band- highlighted with arrows and text overlays (above, figure 4). The nail plate, nail matrix, nail folds, nail bed, hyponychium, blood supply and tendons are are shown using three dimensional illustrations with text descriptions, an example of which is shown in figure 5. The nail bed is described in more detail using an animation (video clip) which illustrates the relationship between the nail bed epithelium and the underlying dermis. In the approach to patients with nail disorders, the importance of the history, physical examination, and laboratory evaluation are briefly discussed and illustrated.

Figure 6a Figure 6b
Figure 6a and 6b: These two screens from the Patterns of Pathology section show an example of dystrophy-longitudinal striations. Figure 6A shows the image without any overlays and Figure 6B, captured after the user selected the overlay button, shows the image with a green overlay that clearly points out the striations. The overlay can be toggled on and off. The user can view other examples of dystrophy by selecting the large buttons across the top of the screen.

In the section on patterns of nail unit pathology, the patterns are classified according to the component(s) of the nail unit most involved. Pathological changes are shown using high resolution images labeled with arrows and text, and for most of the pathological changes there is bulleted text which describes the change and lists the differential diagnosis. For some of the images, the user can click an "overlay" button to completely highlight a given feature in that image. For example, in the screen showing dystrophy-longitudinal ridging (see figure 6), the longitudinal ridges can be highlighted in green when the user clicks an "overlay" button. Similarly, in an image which depicts triangular lunulae, the triangular lunlae can be completely highlighted in green (see figure 7).

Figure 7a Figure 7b
Figure 7 and 7B. These two screens from the Patterns of Pathology section show an example of triangular lunulae. Figure 7A shows the appearance of the screen when the overlay button is toggled off, and 7B shows the screen that resulted after the overlay button was toggled on and after the green underlined text ("lunulae") was selected. These actions led to complete highlighting of the triangular lunulae in the image and to the appearance of the definition of "lunulae" in the lower left of the screen.

The section on the classification of nail disorders teaches disorders of the nail unit, emphasizing 1) classification, 2) typical appearance (using labeled images), and 3) key clinical facts. Nail disorders include acquired diseases, congenital diseases, and changes that occur with aging. Acquired diseases include dermatologic diseases, systemic diseases, fungal infection, other infections, color changes, changes caused by medications, benign tumors, malignant tumors, and trauma. Typical example screens from the nail disorders section are shown in figure 8, which shows one of 4 examples of psoriasis, and figure 9 , which is taken from the onychomycosis section and which shows distal subungual onychomycosis.

Figure 8Figure 9
Figure 8: Psoriasis of the nail. Figure 9: Onychomycosis.

The image atlas section of the program allows one-click access to the most important images from the Nail Pathology and the Classification of Nail Disorders sections of the Nail-TutorTM without having to navigate through the program. Users can access images by pathologic description (e.g., Splitting-Lamellar Dystrophy) or by nail disorders (e.g. Onychomycosis-Distal Subungual). Thirty-two of the images in the Pathology section and 49 images in the Nail Disorders section can be accessed.

Figure 10aFigure 10b
Figure 10: Two nail conditions taken from the full Figure 10.

Images can be viewed one or two at a time. This is illustrated in Figure 10 , which shows the screen that resulted when the user asked to compare two different patterns of pathology which effect the nail plate and matrix: 1) hypertrophy-pachyonychia congenita, and 2) hypertrophy-onychogryphosis. The image atlas is useful for comparing images and as a rapid reference. The final exam contains 20 image-based, multiple-choice questions of varying degrees of difficulty which cover the main topics presented in Nail-TutorTM. Detailed answers are provided immediately after each question is completed. At the end of the exam, the examinee receives his or her score. An example of an exam question and answer is shown in figures 11 and 12. The question asks the user to recognize clubbing.


Nail-TutorTM is intended for a variety of users including medical students, residents, general practitioners, and dermatologists. For medical students, residents, and other trainees, the program is a useful supplement to clinical instruction in dermatology. We recommend that the program be used early in the dermatology rotation so that trainees can rapidly obtain basic knowledge about nail anatomy, pathology, and diseases. Having covered this basic material, students will come to the instructors more prepared to interpret clinical cases and more complex material. This approach to teaching is also advantageous to medical instructors who are freed from teaching basic vocabulary and other monotonous material.

For family practitioners, internists, and dermatologists, Nail-TutorTM is primarily for continuing education. The program is accredited by the American Academy of Dermatology for 3 hours of category I CME, and is useful as a review or as a tool for learning material that might not have been emphasized during professional training. Nail-TutorTM is also useful as a reference since clinical cases can often be clarified by using the program, especially the image atlas, for comparison and contrast.

Nail-TutorTM is not a textbook on computer. Rather, the program takes advantage of computer technology to teach nail anatomy, pathology, and diseases in ways that cannot be easily duplicated by textbooks or supervised instruction. Examples of such computer methods include:

  1. the use of animation (video clip),
  2. use of hypertext to define key terms,
  3. use of optional overlays to highlight areas of interest in an image (figures 6, 7),
  4. the ability to show key images side by side (figure 10)
  5. immediate detailed feedback on exam questions (figures 11, 12).

The approach to teaching shown in Nail-TutorTM can be applied to many problems in medicine. Other tutorials of interest to general practitioners and dermatologists that we are currently completing include a genital ulcer disease tutorial, a clinical mycology tutorial, a clinical parasitology tutorial, a tutorial on the principles and practice of microscopy, and others. Our plan is to continue to develop, distribute, and evaluate the educational effectiveness of our tutorials.

Acknowledgement:The authors thank Dale Davis for developing illustrations, Adam Orkand for help with all aspects of the program, Dr. Seung -Joo Kang for providing the initial idea to develop the program, and Drs. Stephan Billstein and Andrew Morgan , for helpful comments and images.

Additional information about educational software developed by our group at the University of Washington is available on the world wide web at: Nail-Tutor is distributed by Novartis Pharmaceuticals and Lippincott-Raven Publishers. The program is owned by the University of Washington who is responsible for its editorial content.


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