Laboratory instruction in histology at the University at Buffalo: Recent replacement of microscope exercises with computer applications

Abstract

Histology is a morphologic science in which the structure of the cells, tissues, and organs of the body are examined with a microscope. In the laboratory courses in histology at the School of Medicine of the University at Buffalo, histologic specimens had been used since the late 19th century to teach the principles of cell, tissue, and organ structure. Students also had to learn how to analyze or “read” slides with a microscope. Learning histology in this way, i.e., by direct examination of actual specimens, is time consuming and viewed by some as unnecessary. As a result of recent curricular reform at the School of Medicine that reduced contact time in histology, half of all laboratory exercises that would have been performed with a microscope were performed instead with interactive computer applications. By replacing some microscope exercises with more efficient computer applications, the histology course accommodated curricular change by both reducing contact time and continuing to offer valuable microscope laboratories for most of the organ systems of the body. To provide a basis for comparing traditional microscope exercises with computer-assisted instruction in histology, the nature of the laboratory experience between 1846 and 1998 is briefly reviewed. The instructional strategy behind the use of computers is presented, along with the nature of the computer applications and the means by which the computer applications were incorporated into the school's laboratory course in histology. Anat Rec (New Anat) 265:212–221, 2001. © 2001 Wiley-Liss, Inc.

Histology in the broadest sense is devoted to the study of the microscopic structure of the body. It includes the study of the components of cells and organs that are so small that they can only be seen when examined with a light microscope (Arey, 1968; Stedman, 1976). With the invention of the electron microscope, the subject of histology has also come to mean the study of structure that is beyond the resolution of the light microscope.

Even before the end of the 19th century, students at the School of Medicine and Biomedical Sciences of the University at Buffalo (UB) were introduced to the principles of histology (Annual Announcements, 1846–1873, 1873–1895; Batt et al., 1996). Then and in subsequent years, the light microscope (which will be referred to simply as the microscope from this point forward) played a major role in their education. Indeed, at that time it was the best tool for teaching and learning histology, because by using a microscope, students could see how organs were constructed from cells and tissues.

The preeminence of the microscope as a teaching device has been only recently challenged at UB by the replacement of microscopes with computers in the histology course that is taken by first-year medical and dental students. The change was necessitated by a reduction in the total amount of time that was allocated to the medical section of the course. Students required substantial amounts of time to work through microscope exercises, and with the reduction in time, it was necessary to either reduce the instructional content of the course or choose a more efficient way of teaching histology. To compensate for the reduction in contact time, advantage was taken of the efficiency with which laboratory exercises could be carried out with computer applications. In 1999 and 2000, half of the histology laboratory exercises at UB were carried out by using a computer rather than a microscope and additional computer applications were being developed that have the potential of replacing the microscope as the principle means of studying “histological specimens.”

The preeminence of the microscope as a teaching device has been only recently challenged at UB by the replacement of microscopes with computers in the histology course taken by first-year medical and dental students.

THE NATURE OF THE LABORATORY EXPERIENCE AT THE UNIVERSITY AT BUFFALO (1846–1998)

Practically from the time of the medical school's founding in 1846, microscopes and histology have had a place in the medical curriculum at the University at Buffalo, but it was several years before histology was taught as a separate discipline. In the initial years, professors of pathology, physiology, and anatomy used microscopes to demonstrate specimens (Annual Announcements, 1846–1873). In 1887, Practical Microscopy became a required laboratory course, which focused on several disciplines including histotechnology, histology, pathology, and clinical microscopy (Annual Announcements 1873–1895). Between 1890 and 1899, histology was taught in combination with pathology or biology (Annual Announcements, 1873–1895, 1895–1906). In 1900, Histology became a freestanding course and a permanent fixture in the medical school curriculum (Annual Announcements, 1895–1906).

A recently published pictorial history of the school (Batt et al., 1996) shows that students at the end of the 19th century worked at a bench and examined tissue sections with microscopes (Figure 1). About this time, students learned how to use a microscope and prepare histologic specimens. They examined more than 100 microscope specimens and made drawings of what they saw through a microscope (Annual Announcements, 1895–1906).

Figure 1. A microscope laboratory at the Medical School of the University at Buffalo in 1898. The technology of the day was perhaps primitive by today's standards and students worked without the benefit of mechanical stages, built in illumination, projection slides, or the colorful atlases that are common today. In the foreground, students are shown examining specimens. Specimens were illuminated during the day by sunlight and at night with a petroleum lamp (Gage, 1894). In the background, a professor appears to be providing instruction to one of his students. Copyright; the University at Buffalo. Used with permission of the University Archives, State University of New York at Buffalo, Buffalo, New York.

A laboratory manual that was modified from Laboratory Directions in Histology: A Guide for Use in a Laboratory Course of Histology (Kingsbury, 1915) and adapted for use at UB by Rufus R. Humphrey and J. Graham Edwards offers some insight into the use of drawings. As explained in the “Introduction” to their manual, drawings were a key element in the learning process. Students made drawings of specimens (Figure 2) to make “accurate observations and to fix clearly in the student's mind the essential features of the structure” (Humphrey and Edwards, 1942). At the end of the session, the drawings were submitted and corrections made before the drawings were added to a laboratory folder.

Figure 2. An ovarian follicle. This pen and ink drawing, which was rendered in 1985, is comparable to drawings that were made by students in an earlier time. Contemporary medical students at UB are not required to draw specimens and rarely make drawings of what they observe with a microscope. Those that do have a penchant for drawing specimens and tend to be artistically inclined. Copyright Dr. Charlene Vitale Conners, University at Buffalo, State University of New York, Medical School Class of 1989.

Drawing free-hand what an observer saw with a microscope was a common practice at the end of the 19th Century. It was mirrored in the illustrations of many of the textbooks and laboratory guides that were required at UB during this period of time (Orth, 1881; Klein, 1883; Miller, 1891; Stöhr, 1896; Piersol, 1900, Bailey, 1913; Schaffer, 1920; Sobotta, 1930). The illustrations depicted what one was likely to observe, and according to an author of one of the guides, his illustrations were an “aid in the recognition of such elements (histologic structures) in the field of the microscope” (Miller, 1891). Despite the illustrations, he advised students to draw specimens without elaborating on why they should do so. The reasons noted in A Manual of Practical Normal Histology for having students draw specimens were quite practical, because the drawings were made to “make good … the lack of illustrations in the text” and as a means of developing hand eye coordination (Prudden, 1890). According to the author of the Text-Book of Histology Including the Microscopical Technique, drawing a specimen enhanced the power of observation, which in turn improved the likelihood that the less obvious features of the specimen would be seen (Stöhr, 1896). As might be expected, in the absence of formal training or aptitude, some students questioned their ability to transfer what they saw to paper. In one of the guides, they were advised that no artistic talent was “needed to begin with, only patience and a dogged determination to succeed” (Miller, 1891).

Photomicrography, in contrast, was not widely used to illustrate microscopic structure. Among the required textbooks and guides that are listed above, only Bailey's A Text-Book of Histology contained photomicrographs and the number of photomicrographs that was used was small (Bailey, 1913). Although recognized for its ability to capture details that were difficult to draw (Munson, 1898), photomicrography was not widely used at the end of the 19th century, because it was technically difficult and the photographic equipment that was required was expensive (McClung, 1901; Potter, 1900).

For the next 100 years, students continued to study cells, tissues, and organs by direct observation of the specimen. To this end, students had to learn to use a microscope. For casual onlookers of the discipline, this was usually taken to mean learning how to operate a microscope. Those who had to use a microscope, on the other hand, discovered that examining specimens involved much more than simply learning how to adjust the illumination, fine focus, use the oil immersion lens, and adjust the interpupillary distance of the ocular tubes once binocular microscopes were introduced into the laboratory. Examining specimens required that they learn how to “read” microscope slides (Reith and Ross, 1970; Cotter and Breen, 1996).

For a tissue or organ to be examined with a microscope, small samples were obtained and cut into very thin slices or what are commonly referred to as tissue sections. A tissue section was then mounted on a glass microscope slide and stained with dyes so that the components of the tissue, which are colorless, could be seen.

In “reading” a slide, each student was expected to methodically examine the section of tissue. The goal was to relate what was seen with a microscope to what was known about the histologic structure of the specimen (Miller, 1891; Reith and Ross, 1970; Cotter and Breen, 1996). The general pattern of organization was considered at low magnification followed by the identification of specific cell types, structures, and subdivisions that composed the specimen. The various parts were first located by scanning the specimen at lower magnifications. They were then studied in detail at higher magnifications. In the process of examining the tissue section, the cells, tissues, and structures that were characteristic of the specimen were identified by their morphology (size, shape, cell grouping, or layering) and location. In addition, the effects that dyes, histochemical staining, cutting angles, histologic processing, and experimental manipulations had on their appearance had to be taken into account.

Laboratory instructors supervised the microscope laboratory and provided assistance to students who had difficulty interpreting what was seen with a microscope. They confirmed the identity of structures, helped students find structures, and identified structures that students did not recognize.

In 1915, in addition to the tissue sections that they stained and mounted on glass slides, students were given specimens from a permanent collection of student slides. The next year, the school recommended that every student purchase a microscope (Annual Announcements, 1906–1917). Eventually histologic techniques were taught separately; students prepared only a few slides, and most of the slides that they used came from the teaching collection. In 1942, approximately 165 histology slides were provided (Humphrey and Edwards, 1942). Fifty years later, the collection had swelled to 194 different specimens, containing examples of most of the organs and a variety of smaller structures and tissues. Only normal material was used. The material was obtained from the gross anatomy laboratory, area hospitals, and research laboratories. It was prepared within the department, and it included human and animal specimens. In some instances, commercially available microscope slides were purchased to augment the collection. Currently, the student collection numbers 180 slides.

Each microscope specimen in the collection was selected to demonstrate a morphologic feature or group of features that is characteristic of a cell, a tissue, or an organ. Because all the pertinent features were not necessarily found on a single slide, sometimes more than one example of an organ, a different stain, or another preparation was required. In total, nearly two dozen different staining methods were used. They ranged from stains that were used to stain cells and the extracellular matrix to more specific histochemical stains that were used to define the biochemical composition of the cytoplasm and nucleus. The preparations included paraffin- and epoxy-embedded sections, frozen sections, tissue spreads, and dry film smears.

The microscope slides were eventually made from one or several blocks of the same tissue sample rather than from different samples. In this way, each student had comparable slides. However, each slide specimen was also different, sometimes markedly so, because the structure of an organ changes from specimen to specimen in much the same way the use of space in a building changes with the architecture of the building. In one veteran instructor's view, the unpredictability of the morphology was advantageous, because by having to deal with variations, students got to see for themselves what it meant to do microscopy. The variations drove home the point that one could not count on every tissue section being exactly the same as another (Hayes, personal communication).

If it was not realized while working with specimens, the uniqueness of each microscope slide became apparent during practical examinations (Figure 3). The examinations tested a student's ability to identify structures from unlabelled microscope slides (Humphrey and Edwards, 1942) and very often without the benefit of scanning the specimen or viewing the specimen at different magnifications. Our predecessors noted that laboratory examinations had other virtues as well: “such practicals will serve to test the student's knowledge of Histology; their greatest value, however, lies in the opportunity they offer the student to determine his real mastery of the subject, and in the increased alertness and power of observation which they effect” (Humphrey and Edwards, 1942). In other words, students had to demonstrate that they could “read” a slide or a very limited area of a microscopic field. In recent times and in all probability in earlier times as well, students who mistakenly assumed that the practical examination was a test of recall learned that the greatest challenge they faced in histology was learning to “read” rather than memorize the specimens that they were given to study.

Students who mistakenly assumed that the practical examination was a test of recall learned that the greatest challenge they faced in histology was learning to “read” rather than memorize specimens.

Figure 3. The practical laboratory examination in 1987. In this type of examination, students were tested with specimens that were viewed with microscopes. The specimens were taken from the permanent slide collection and other sources as well. Students were most often asked to identify a cell, tissue, organ, or structure. In most cases, the field of view was restricted to a specific location in the slide specimen and by the magnitude of magnification. If an organ was to be identified, the student was often given more latitude. The slide was placed on a light box so that the tissue section could be viewed in its entirety and studied with an inverted ocular before it was examined on the microscope stage at different magnifications. This type of examination was used as late as 1992, after which time comparable fields of view were recorded on videotape and projected onto a large lecture hall screen.

The commitment to examining specimens was strong, and in 1970, the school supplied every student with the binocular microscopes that are used today. The microscopes had a mechanical stage and an internal light source; they were often superior to the ones that students had previously brought to class. The impact of providing professional level microscopes (and the same microscope slides) was that the laboratory experience was much more uniform for each student (Glomski, personal communication). In the late 1980s, the commitment to microscopes was reaffirmed with the purchase of nine multiviewing microscopes. With these microscopes, as many as five people simultaneously viewed the same specimen. They were used for independent small group learning and tutorials.

During approximately the past 30 years, various editions of three atlases were required: Atlas of Descriptive Histology (Reith and Ross, 1970, 1977), Functional Histology: A Text and Colour Atlas (Wheater et al., 1979, 1987), and Wheater's Functional Histology: A Text and Colour Atlas (Burkitt et al., 1993; Young and Heath, 2000). These photographic atlases filled a void that was created by viewing the specimen in the absence of an illustrated laboratory manual by providing examples of specimens that were comparable to those studied in class. Although textbook illustrations could be used as a reference, they were not intended to help students “read” microscope slides. In contrast, the first of this group of atlases were purposely “designed to assist the student” when faced with the task of correlating what was seen with what had to be learned from the microscopic specimen (Reith and Ross, 1970). The color atlases that were used later also served this purpose and contained photomicrographs that were even a closer match to the specimens used in class.

Before the adoption of photographic atlases, the use of an atlas had not been favored and illustrated textbooks could be used as a reference (Hayes, personal communication). Furthermore, in drawing specimens, which was required at UB as late as the 1950s (Jason, personal communication), students created a personal atlas of their work. An indication of how pervasive this approach was in the 1950s is found in the Handbook of Microscopic Characteristics of Tissues and Organs. In the “Preface” to the 3rd edition, the author points out that “many teachers require their students to make laboratory drawings in the Handbook, thus making it more valuable for reference purposes.” The author goes on to say that “histology instructors in general have a conviction that the Handbook will be of greater value to the student if he furnishes his own illustrations made from actual preparations studied in the laboratory” (Stiles, 1950).

Because of the uniqueness of the specimens, many students had difficulty relating what they were told, what they read in textbooks, and even what was depicted in atlases, to what they saw in their specimens (Cotter and Breen, 1996). The difficulty of the task, which was formidable, compelled the faculty to develop various aids that were intended to help students understand the work. From the beginning, laboratory exercises were supplemented with demonstrations of structures that were seldom seen in sectioned materials, difficult for students to find on the slides, or required special preparations or applications, e.g., dark field, phase contrast, and electron microscopy. Generalized laboratory guides were replaced with laboratory manuals that explained how each slide in the permanent collection was to be studied. Moreover, with advances in technology, the faculty was able to author audiovisual aids that were also expressly designed for the laboratory. In the 1970s, E. Russell Hayes augmented the laboratory work with a series of self-instructional 35-mm transparencies that were accompanied by a description of the slides recorded on audiocassettes, and in the early 1990s, John R. Cotter produced a series of videotapes that guided students through each microscope exercise. The videotapes were used in conjunction with microscope laboratories.

Students were shown what to search for and how to go about finding structures to identify on each slide. The videotapes, shown immediately before each laboratory, were made available for study outside of scheduled class time.

THE IMPACT OF CURRICULUM REFORM ON HISTOLOGY AT UB (1999–2000)

Many medical schools are in the midst of changing traditional basic science curricula to accommodate the educational needs of modern day students (Drake, 1998; Hightower et. al., 1999, McMillan, 2001). At UB, there has been an ongoing effort to revamp the curriculum and, in the near future, the school will implement an integrated curriculum that accommodates self-learning, reduces contact time, and incorporates problem-based learning.

The impetus for changing the nature of instruction in the histology course at UB presented itself in the spring of 1999 during the second phase of the school's effort to restructure the curriculum. At the time, the number of hours that was devoted to histology and other basic science courses became a critical issue in the school's attempt to decompress the curriculum and sustain problem-based learning that had already been incorporated into the curriculum during the first phase of curriculum reform.

All basic science courses that were taught in the first year at the medical school agreed to cut instructional time. In the case of histology, 67.5 hours of laboratory time was reduced 13.9 hours to 53.6 hours, or 79.4% of the total amount of time that was devoted to laboratory in 1998.

Initially, a 40% cut in total contact time for the histology course was proposed. When faced with such a drastic prospect, the decision was made to replace some microscope exercises with computer applications that had been crafted specifically for the histology laboratory. Previous experience with computer applications had shown that the basic principles of histology could be learned without a microscope and without “reading ” microscope slides (Cotter, 1997). The report also showed that the amount of time required for computer applications was less than the amount of time that was set aside for “reading” slides and that students could apply principles that were learned in the computer laboratory to histologic specimens.

INTEGRATION OF COMPUTER APPLICATIONS INTO THE HISTOLOGY LABORATORY

Computer applications were integrated into the histology laboratory during the first half of the histology course by replacing microscope exercises on the light microscopy of cells, all the basic tissues, blood vessels, and the integumentary system with computer applications dealing with these topics. In using the applications, digitized images replaced glass slides and the time that would have been normally spent in the microscope laboratory analyzing specimens and learning the basic morphology with a microscope was spent exclusively learning the morphology that was captured in images of specimens. The net effect of replacing the microscope exercises with computer applications was that student contact time was cut without either loss of instructional content or the abandonment of microscope exercises altogether. Furthermore, by using computer applications for topics that were prerequisite to working with organs, the very real impediment of studying the cells and tissues of organs with a microscope before being introduced to the structure of the organ itself was overcome. In place of searching for cells, organelles, tissues, and other structures in organs with which students were unfamiliar, the structures were displayed on computer screens. In addition, students were prepared by the computer applications for the traditional microscope exercises dealing with the organ systems that were studied during the second half of the course. Having learned the fundamentals of cell structure and tissue organization by means of computer applications in the first half of the course, students were poised to apply what was learned to the organs that were examined with a microscope in the second half of the course.

The net effect of replacing the microscope exercises with computer applications was that student contact time was cut without either loss of instructional content or the abandonment of microscope exercises altogether.

THE NATURE OF COMPUTER APPLICATIONS FOR HISTOLOGY AT UB

The computer applications are highly structured programs of instruction in which the principles of practical histology are conveyed through interactive screens that combine digitized images of specimens along with fields of instructional text (Cotter, 1994, 1997; Cotter and Breen, 1996). An explanation of key points is displayed on the computer screen adjacent to an image (Figure 4), and the salient information about a topic is presented as a student progresses in a linear manner through an application. Just as with traditional microscope exercises, the recognition, classification, and characteristics of cells, tissues, and organs are of paramount importance.

Figure 4. A typical computer application. This screen shot is from the application on nervous tissues. Interactive screens such as this integrate images of histologic specimens with instructional text that explains what is depicted in the image. Hotwords (underlined) and magnification buttons (lower right) are powerful interface tools that are an integral part of the application. Selecting hotwords by clicking on them with a mouse cursor links the terms that are used for histologic structures to the appropriate portion of the image. Searching for and locating the structures in histologic specimens and the need to confirm that they have been correctly identified is eliminated. Magnification buttons increase and decrease the magnitude of enlargement. A bar menu across the top of the window and buttons at the bottom permit navigation within and between different laboratory exercises.

The applications are self-instructional; this approach is facilitated by links that students must activate to relate histologic terms used in the instructional text to the location of the structures in the accompanying image. Faculty, nonetheless, are present during laboratory sessions to explain the interactive features of the applications, assist with technical problems that may arise in the use of the applications, and answer questions concerning the instructional content of the applications.

DELIVERY OF THE COMPUTER APPLICATIONS

In 1999 and 2000, the histology course at UB was taught to both medical students (n = 127 in 1999; n = 134 in 2000) and dental students (n = 80 in 1999; n = 89 in 2000). Both sections attended lecture together but had laboratories on different days. Class time was set aside for study and completion of the applications in the medical school's central computer laboratory.

Students were expected to work through the applications in the time provided and ask questions about information that they did not understand. In the case of most exercises, the length of time was adequate. In cases (electron microscopy, hematology, and nervous tissues) when more time was needed to cover more content, two sessions were scheduled.

METHODS OF ASSESSMENT

Student learning was evaluated by multiple choice examinations that were constructed from images used in the applications as well as from images that students had not seen before the examination.

The first year that computer applications were integrated into the course, students identified cells, tissues, and structures from images that were projected over a range of magnifications onto a large lecture hall screen. The images were customized by using computer software, organized into a multimedia slide show and converted to a computer presentation (Szczesny and Cotter, 1995). In the second year, a print version of the laboratory examination was given in conjunction with the lecture examination. Some of the questions tested the students' ability to identify structures, but many questions had a distinct functional bias. Black and white photomicrographs were used because of the expense involved in making color prints.

CONSIDERATIONS

Use of Computer Applications in the Histology Laboratory

The fundamental nature of the laboratory course in histology at UB did not change until the introduction of computer applications 2 years ago. Near the end of the 19th century and in the over 100 years that have intervened, the goal of the students who took the laboratory course in histology was to learn the microscopic structure of cells, tissues, and organs by examining specimens with a microscope. In 1999 and 2000, that goal was achieved not only by examining microscope slides with a microscope but also by examining images of histologic specimens that were displayed on a computer monitor.

The long tradition of using a microscope and the perception that the best way to learn the microscopic structure of the body was by “reading” microscope slides with a microscope made it difficult to immediately replace microscope exercises with computer applications. The applications underwent several years of testing and revision. Once that was accomplished, the change was made. Being convinced that learning the basic histology of cells and tissues was not diminished by computer applications, the decision to replace microscopes with computers was a relatively easy one to make, especially when faced with choosing between reducing course content or replacing microscopes with computers.

In some respects, learning to use a microscope is similar to learning to play a musical instrument. Continuing the analogy: learning to extract the intricacies of morphology that are to be discovered in any histologic section by “reading” slides is akin to learning to play a piece of music. To be successful, practice, a certain amount of talent, and a desire to succeed are essential. Allocating a sufficient amount of time for learning these skills is also a basic requirement.

The difficulties that students have working with histologic specimens are well-known to laboratory instructors (Alper and Cardasis, 1992; Cotter and Breen, 1996; Lehmann et al., 1999). It may take weeks—perhaps as many as 12 in a typical semester course—before a student becomes proficient and comfortable with the mechanics of the microscope and confident in his/her ability to find and identify structures in specimens (Cotter and Breen, 1996). Students who do not appreciate the value of learning to “read” slides or who do not use the time given to the curriculum for learning to “read” slides are likely to have the most difficulty as well as the strongest negative reaction to histology. Unfortunately, if the situation remains unresolved, the end result is a discontented student who is unable to cope with the laboratory work and overly dependent on his/her laboratory instructor.

The computer applications that were used overcame many of the difficulties and aversion that students may experience when working with microscopes and microscopic specimens. The reasons for this are twofold: first, “reading” is eliminated by the use of selected images; and second, the applications provide a structure that guides students in their study of the images. Although assistance is given in the microscope laboratory, instruction is difficult even when it is one-on-one, because the microscope can create a barrier that inhibits effective communication between the student and instructor. Images are idealized snapshots of complex specimens, and the components of the specimen can be presented without ambiguity. Compared with histologic specimens, students require less help with images and fewer instructors are needed to oversee the laboratory experience.

If taken to the extreme, students could potentially study well-designed applications anywhere and at any time as long as they have access to the appropriate hardware. This may or may not be desirable. If the faculty who teach histology decide that it is desirable, then they will need to devise a means of communicating with students, because some are certain not to attend class during scheduled laboratories.

Curricular reform at UB emphasizes self-directed study, small group learning, and problem solving. These types of activities are incompatible with curricula that are so compressed that students do not have sufficient time to give adequate attention to all subjects studied in the basic science years. To make time in the curriculum for these activities, time in the weekly schedule was made available by reducing contact time in basic science courses. In histology, the goal of reducing contact time was achieved by taking advantage of the efficiency with which laboratory exercises could be accomplished with computer applications. Although this approach to laboratory histology was a radical departure from what had been done in the past, the replacement of microscope exercises with computer applications satisfied the need to cut contact time. Most importantly, from the standpoint of the integrity of the course, by using the computer applications, contact time was reduced without compromising course content. For example, in the computer application on epithelium, all the tissue types that had been studied with microscopic specimens and all the surface specializations that had been studied with microscopic specimens and electron micrographs were studied with images of specimens and electron micrographs.

These computer applications are comparable to microscope exercises in that they can be used to learn the histology of tissues and organs. They do not replace all the activities that are possible with optical microscopes. Unlike either optical microscopes or virtual microscopes—which aim to replace optical microscopes (Harris et al., 2001)—students do not learn the thought processes and strategies that are used in analyzing real specimens when using computer applications.

At UB the computer applications were available only on the school's local area network during and outside of class time that was scheduled for laboratory. Students nonetheless frequently asked whether there was a way of making the applications available outside the confines of the medical computer laboratory. Consideration was given to producing a workbook that contained the screens of each exercise, especially because many students routinely made hard copies of the applications by printing screens. However, the idea of a workbook was viewed as impractical because of the high cost of color reproductions and the inability to transfer the interactive features of the applications to a hard copy. Because all the information that is contained in an application could not be mastered in one sitting, the students' request was reasonable and one that could be dealt with by distributing the applications by means of compact disk or over the Web.

During the period of time leading up to the first laboratory examination each year, there was some student anxiety about the method with which the images were to be presented. Students expected that they would be presented on a computer screen as they had been in the computer applications. Without the symmetry between the method of learning and the method of testing, students were concerned that they would not be prepared to sit for an examination in which the images were presented in a totally different manner.

Alternate methods of testing were used, because the computer laboratory could not accommodate the entire class at one sitting. Several solutions to the testing issue are being explored. One is to use the computer laboratory as the testing venue, and write multiple examinations for different classes. Another is to provide students with sample questions in a format that is representative of the examination.

Use of Microscope Exercises in the Histology Lab

Before the development of computer applications for histology, the accepted method of teaching and learning practical histology at UB was with a microscope. It was indeed a time-honored method of teaching and learning that was passed down to students year after year and from one generation of instructors to the next.

Students explored the microscopic details of an entire specimen, analyzed the tissue section in three dimensions, related what they saw to reference materials and information provided in class, and made decisions about the identity of structures or their absence. By using a microscope, students were exposed first hand to the pitfalls of using delicate specimens that were treated with chemicals, sectioned, and stained. By using a microscope, students learned how to comprehend what they saw when they peered into the ocular tube(s) of the microscope.

The value of the microscope as the primary means of studying laboratory specimens cannot be appreciated unless it is contrasted with other means, in particular, photomicrography. Anyone who contrasts the photomicrographs of atlases or digitized images of computer applications with fields of specimens that are viewed with a microscope will realize that there is no comparison. For sharpness, depth of focus, and overall clarity, direct observation of the specimen with a microscope is unsurpassed.

The outcome of studying specimens with a microscope may be less obvious. In the opinion of the histology faculty at UB, the process leads to a deep understanding of the microscopic specimen and the overall organization of organs. Furthermore, there are features of the learning environment that may be overlooked by those who are unfamiliar with or oblivious to the nature of the histology laboratory. Every student has the opportunity to reach conclusions regarding the structure of the specimen or structures contained in the specimen, to share those observations with their peers, and to discuss them with laboratory instructors. Such activities provide opportunities for problem solving, active learning, and small group interactions, and they are—in the author's opinion—compatible with the expressed goal of modernizing the curriculum and meeting the needs of today's students.

EPILOGUE

Mindful of the goals of the medical curriculum at UB and the difficulties that are associated with teaching histology, we took advantage of what was considered to be the strengths of teaching histology with computer applications and microscope exercises. During the first half of the histology course, computer applications were used to introduce students to the structure of cells, tissues, blood vessels, and one organ system. Learning was programmed and defined by the images and instructional information that was accessed through a computer application. The strategy allowed students to concentrate on learning principles of histology without being distracted by the conceptual challenge of “reading” microscope specimens. At the same time, the efficiency of the computer applications provided relief from the constraints imposed by a reduction in contact time.

The histology courses at UB have always provided medical students with a foundation for understanding the basic science that underlies the practice of medicine. The laboratory component of the course also ensured that students were schooled in the use of a microscope. Without the microscope skills that were learned in histology, students would not have been prepared to undertake laboratory courses in pathology, microbiology, and hematology or clinical rotations/clerkships in which proficiency with a microscope and an understanding of normal histology was and is still taken for granted.

Nevertheless, the value of microscope laboratories in the training of a 21st century physician generates debate among those engaged in the education of medical students (Harris et al., 2001; Jones, 1997). Given the suitability of computer applications for histology, one can only ponder what the future holds for traditional methods of instruction with a microscope. Detractors emphasize the decline in use of the microscope—or, more precisely, the dearth of microscopy—in the practice of medicine. The use of the microscope or even the application of histologic knowledge in medical practice, however, is often related to an individual's specialty, training, and/or approach to delivering health care. Because it is difficult to predict exactly how a future physician will use histology, perhaps medical education would be better served by placing more emphasis on the richness of the medical school experience and the depth with which its graduates understand human biology and its relationship to medicine.

Given the suitability of computer applications for histology, one can only ponder what the future holds for traditional methods of instruction with a microscope.

If histology courses are to entirely replace microscope exercises with computer applications, students will no longer have to learn how to apply their knowledge of histology to the analysis of histologic specimens. Current plans at UB envision developing applications for all topics in histology, but there are no plans for replacing microscope laboratories entirely with computer applications, even as the school is on the verge of implementing an organ-based curriculum. In the new curriculum, contact time will be greatly reduced and histology for medical students will no longer be offered as an independent course. The authors of the curriculum (many of whom hold medical degrees), however, recognize the relationship of histology to other basic science subjects and clinical medicine and the role of the laboratory experience in learning microscopy. They have not chosen to exclude histology or microscope exercises from the curriculum. In fact, it seems that histology will be taught virtually as described in this report, i.e., in a hybrid form in which computers are used in sections of the new curriculum that deal with cells and tissues, and microscopes are used in sections that deal with organ systems. The major difference is that histology lectures and laboratories will be selectively integrated into organ/system modules along with the other basic science disciplines. As a result, it is expected that students will continue to learn to “read” histologic specimens.

Acknowledgements

I thank Linda A. Lohr (Manager of the Robert L. Brown History of Medicine Collection) for her assistance locating the relevant historical references used in this study; Kathleen M. DeLaney and Daniel DiLandro (University Archives) for locating the picture that was used as Figure 1; Mary Glenn and Nancy Druar (Office of Alumni Affairs) for locating graduates of the school; Dr. Charlene Vitale Conners for her drawing of an ovarian follicle; the Office of Medical Computing for their assistance putting up applications for histology on the school network; Timothy L. Bleiler, Brian J. Schroeder, and Mark Schneggenburger (Health Professions Information Technology Partnership) for creating the authoring software used in the production of the application on the cardiovascular system; Ted Szczesny for his assistance printing Figures 2, 3, and 4; Drs. E. Russell Hayes, Chester A. Glomski, Roberta J. Pentney, Harold Brody, Dennis Nadler, and Denise Cotter and Daniel Cotter for their helpful reviews of the manuscript; Drs. Ronald Batt, Daniel Conny, Chester Glomski, E. Russell Hayes, Hilliard Jason, Norman D. Mohl, Roberta Pentney, Bertram Portin, Kenneth Raczka, and Joseph Zambon for discussing their experiences in the histology course; Dr. Susan Gallagher for discussing the importance of microscope work to medicine; and the histology faculty (Drs. Cynthia Dlugos, Roberta Pentney, Chester Glomski, and Herbert Schuel) for their interest in and continued support of computer-assisted instruction in the histology course.

Biographical Information

Dr. Cotter is an Associate Professor in the Department of Pathology and Anatomical Sciences at the University at Buffalo. He has lectured on all topics in histology and taught practical histology for 26 years. He was director of the histology course for medical and dental students at the School of Medicine and Biomedical Sciences of UB between 1979 and 2000. He is currently the director of the histology course for dental students. His interests are in the development and evaluation of instructional aids.