At UMDNJ-New Jersey Medical School, we took a new approach in teaching histology to first year medical students. In keeping with the new trend in curricular change, we focused primarily on two objectives: 1) to make histology as clinically relevant as possible and 2) to reduce the lecture time. The core strategy of our approach was to make the laboratory sessions more efficient and effective in both teaching and learning. We implemented two changes to accomplish our goals. First, we equipped histology laboratories with an “Audiovisual Switching and Projection System”. The technology enabled us to project images from: a) glass slides, b) 2’x2″ slides, c) textbook figures and photomicrographs, or d) videotape. Second, we switched from a traditional Lecture-Laboratory-Review sequence to a Laboratory-Lecture-Conference sequence. Each topic starts with a live pre-lab presentation by a topic expert who guides the students in observing the basic histological features to be studied in that laboratory session. Afterward, the students complete the laboratory exercise. Lecture time is used primarily to emphasize the structure-function relationships. The Conference uses structure-function relationships as the basis for a meaningful discussion of clinically relevant topics. With the new approach, we have reduced lecture time from 43 hrs to 34 hrs and moved away from the histological detail previously presented in lecture. We believe that this approach prepares students for subsequent medical training by enabling them to remember the useful and clinically relevant aspects of histology.
As medical schools continue to implement new curricula, it has become imperative for faculty, particularly in the basic science disciplines, to adapt by adopting new approaches and strategies. In general, new curricula entail a) increasing emphasis on disciplines such as immunology, b) introduction of the art of medicine alongside basic science programs, c) radical changes in basic science programs to emphasize clinical relevance, and d) major reductions in the contact time available for basic science programs. In this challenging scenario, the need to devise a more innovative and efficient methodology became obvious. At our institution, we focused on the laboratory component first because it is a significant segment of the Histology course, and appeared to be the logical place to look for a variety of possibilities.
Our first year class of about 180 students is divided into four groups and assigned to the four adjoining laboratories. We set out to run the laboratories with a centralized approach. In this effort to reorganize the physical facilities, we established a studio hooked up to the four laboratories with an “Audiovisual Switching and Projection System” (ASPS; Hacker Audio Video Communications, Hackensack, NJ). The ASPS technology enables us to project images from a) glass slides of actual histological sections using an Olympus BH-2 microscope equipped with a Sony 3CCD camera, b) 2″x2″ slides using a NAVITAR Videomate Slide-to-Video System, c) photomicrographs and textbook figures via an Elmo EV-6000AF Visual Presenter, or d) a videotape (Fig. 1).
The centralized system provides a great deal of flexibility, with almost no time wasted in switching from one source to the other. From the studio, images are projected onto a screen in each laboratory via an LCD projector. Using these images and the two-way audio system, an instructor is able to give an oral presentation to the entire class with ease. The two-way audio system provides a mechanism for students to ask questions and to give helpful feedback to the presenter.
With the physical facilities of the laboratories radically changed, we then undertook another substantial change. We abandoned the traditional Lecture-Laboratory-Review sequence and instituted a Laboratory-Lecture-Conference approach. In this new format, each topic starts with a live pre-lab presentation by a topic expert. The students are guided to observe the important histological features of the tissues or organs during that exercise. After about 20 minutes of the pre-lab presentation, which is part of the laboratory session, students use short written instructions and an atlas to complete the exercise. Laboratory instructors are available in each laboratory to help students needing further assistance during the remaining time of each 2-hr laboratory session.
Lecture time is used primarily to emphasize structure-function relationships, after a brief review of descriptive histology. The Conference, which replaced the old Review, is designed to use the structure-function relationship as the basis for meaningfully discussing selected topics of clinical relevance in the context of histology. The Conference was done in the lecture format and focused on clinical scenarios in the context of histology. For example, under histology of pars distalis of the pituitary, acidophil tumors are discussed by introducing amenorrhea and galactorrhea in women, along with symptoms of visual defects. This approach is much more helpful than the Review, the purpose of which was to merely recapitulate the material covered in the lecture and laboratory sessions.
Medical, and dental, schools around the country have been working hard to develop innovative approaches in histology (and other basic science disciplines) in keeping with the evolving curricula. At Loma Linda University, for example, well-prepared exhibits have been used as an adjunct to facilitate the study of glass slides with microscopes1. In preparing these exhibits, low- and high-power micrographs were obtained as digitized images from glass slides. Using Microsoft Word software, the images from each slide were inserted on a single document page, with labeling and annotation. The labeled features were linked to the appropriate document page on the CD atlas. In addition to printed copies of the atlas, students received a CD of the MS Word files for a token fee. With this elegant approach, students were able to readily identify the exact field of the labeled features. In addition, “practice unknown slides”, together with 10-15 micrographs and questions about labeled features, were included for student self-evaluation. The important aspect of the Loma Linda approach is that the traditional use of microscopes in the histology laboratory is preserved. In fact, McMillan1 states “It is recognized that these media cannot replace experience with the microscope and that there is a cognitive dissonance of completely replacing microscope study”. We at New Jersey Medical School are inclined to agree with this pedagogic philosophy. In fact, we believe that microscope study has the additional value of sharpening the observational skills of students, an important attribute in the practice of medicine.
Harris et al.2 at the University of Iowa tested the more sophisticated and technologically advanced approach of Virtual Microscopy to replace use of microscopes and the traditional laboratory sessions. Nineteen slides from the endocrine, urinary and male reproductive units of the Histology course were selected. Their Virtual Microscope Laboratory consisted of the syllabus, gross images for microscopic correlation, and links to additional Histology web sites. Viewer plug-in navigational tools allowed the user to zoom in and out through six levels of magnification, and to click and drag the slide in an x-y axis through the entire surface of the virtual slide. As one can expect, student responses varied widely. Although they greatly appreciated the virtual microscope laboratory, they thought it was a valuable adjunct, and should not replace the traditional histology laboratory. Furthermore, without an instructor present, it was difficult for them to find many structures. Some students did feel that the Virtual Microscope Laboratory would save time. Also, students gave high ratings to the ready accessibility and efficiency of this approach.
Cotter,3 on the other hand, reported a middle of the road approach taken at the University of Buffalo. The histology faculty of his institution took advantage of the strengths of teaching histology with both computer applications and microscope exercises. Cotter3 emphasizes that there are no plans at the University of Buffalo to replace microscope laboratories entirely with computer applications. Instead, they seem to favor the hybrid approach, which entails computer use for cells and tissues and microscope exercises for the organ systems. This dual approach obviously addresses the differing reactions of students.
We believe that the new approach we took in the Histology course at UMDNJ-New Jersey Medical School is very different, if not unique, meriting a close look at certain beneficial features. Moving away from the deeply entrenched Lecture-Laboratory-Review format was a breakthrough in itself. Making the laboratory session the starting point of each topic was clearly beneficial. It addressed the now popular concept of self-directed learning. Students are made responsible to acquire mastery of basic histology in each topic without having to go through the monotonous and time-consuming lecture approach. It also enabled us to reduce the lecture time from 43 hrs to 34 hrs. ASPS made the laboratory exercises more efficient and more interactive. It made it possible for the topic expert to give a live presentation to students in all four laboratories, so that every student received the same benefit of guidance and useful tips. In our experience, the live presentation is certainly superior to the prerecorded presentation we used previously. It allows the presenter to scan glass slides under a microscope, pointing out the histological details. This approach greatly facilitates the students’ task of completing the laboratory exercise. In addition, it permits impromptu innovation for the presenter every time. This approach is so effective that the two-way audio, which works well, does not seem to be critical. Nevertheless, we are inclined to upgrade the equipment further to encourage students to take advantage of the two-way communication system.
Reduction of lecture time was accomplished through three steps. First, teaching and learning of descriptive histology was accomplished in the histology laboratory. Second, the lecture time was used primarily for focusing on the structure-function relationships. Third, the minutiae of histological detail were largely eliminated. Replacing the Review by the Conference was another major feature of great significance. In keeping with the modern trend in curricular change in the basic sciences, clinical relevance of each topic in the Histology course was thus made a major theme. For this to become successful, however, topic experts have had to retrain themselves to acquire familiarity and competence in selected areas of pathophysiology. The time and effort involved were essential to be able to present topics of clinical relevance in an appropriate and accurate manner.
When we introduced our new approach in teaching the Histology course four years ago, we did not consider the possibility of incorporating the Virtual Microscopy Laboratory. However, this possibility is currently being studied, partly because of the convenience this technology provides to students, and partly because of the cost that would be entailed in replacing the aging microscopes for our class of about 180 students. As we cautiously evaluate various possibilities, we are inclined to embrace the hybrid approach described by Cotter,3 at least as a first step. However, we are cognizant of the fact that technology behind Virtual Microscopy Laboratory continues to be steadily and rapidly refined, and has the potential to become widely accepted and implemented.
- McMillan, P.J. Exhibits facilitate histology laboratory instruction: Student evaluation of learning resources. Anatomical Record. 2001; 265: 222-227.
- Harris, T., Leaven, T., Heidger, P., Kreiter, C., Duncan, J. and Dick, F. Comparison of a Virtual Microscope Laboratory to a regular laboratory for teaching histology. Anatomical Record. 2001; 265: 10-14.
- Cotter, J. Laboratory instruction in histology at the University of Buffalo: Recent replacement of microscope exercises with computer applications. Anatomical Record. 2001; 265: 212-221.
NOTE: Please refer to the complete PDF file for the referenced Figures.