How to examine Histology slides
Whether you are learning Histology, taking a Histology exam or you are working with micro preparations, this strategy can help prevent mistakes when identifying each slide under a microscope.
1. Inspection: Inspect the slide using just your eyes and a good light source to first determine the shape of the prepared section. Occasionally, a specific section has a characteristic shape and is much easier to identify. e.g on the cross section of tracheal cartilage an annular preparation can be seen.
2. Calibration: Place the slide under the microscope and calibrate the microscope so that the image produced is clear. Move the slide around so that its entire surface can be seen and check it with different lenses and magnifications. This is important because:
- there are always major and minor structures on the preparation that might not always be visible with a single lens or magnification e.g in the ileum Peyer’s patches are large and characteristic, whereas the other cells are smaller and not so defined.
- because the slide is always bigger than the lens so in order to view all the structures it must be moved around e.g a blood slide contains many different cells and they are not always evenly distributed.
3. Description: Write down a description of the major and minor structures that can be seen and name the ones that you are sure of e.g red, discoid-shaped cells, in close proximity = Red Blood Cells
4. Determination: Determine the staining, sectioning and preparation process of the slide e.g eosin or silver nitrate staining, in longitudinal or cross section, frozen and sliced etc.
5. Identification: Once you have collected all the necessary information, try to piece the evidence together and through a process of elimination, identify the slide.
6. Completion: Add all additional information to your notes e.g cell functions, extra information mentioned by teachers etc.
7. Remember! Never jump to any conclusions, even if you are sure which micro preparation you have. Review all of the content at your disposal and only then, identify your slide.