Histology

Why I Chose the Medical Laboratory Profession

/ Maria Roussakis

I am always thankful to be working as a medical laboratory technologist, a career I am very passionate about. I remember my journey towards discovering my ideal career, and let me tell you, it was not an easy one. I was in a similar situation as many other students in high school, not fully aware of the range of career options available. I completely understand how many high school students can feel stuck, undecided, and anxious on their career choices prior to entering further studies. This can result in students choosing an educational path without making an informed decision of all the career options available to them. As a result, there are many new graduates who have trouble finding a job within their field and pursue additional programs in order to acquire more qualifications. I believe a thorough search of the vast number of career options available will help students make an informed decision.

maria in lab

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Lab Chronicles: My Experience in the Histology Lab – Week 4, 5, and 6

/ Maria Roussakis

Throughout my final weeks in the Histology lab, I performed a variety of special stains in order to detect connective tissues, carbohydrates, microorganisms, and pigments in the diagnosis of certain diseases. I also performed immunohistochemistry in the detection of cancer markers. In a routine hematoxylin and eosin stain, many of these components are not visible and special stains are needed in order for them to be seen.

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Lab Chronicles: My Experience in the Histology Lab – Week 3

/ Maria Roussakis

Throughout this week in the Histology lab, I was operating the automated hematoxylin and eosin stainer, while also submitting stained slides to the pathologists to be reviewed.

Hematoxylin and eosin is a stain used in routine Histology slides. The hematoxylin stains nuclei in the tissue blue, whereas eosin stains the cytoplasm and other structures varying shades of pink. Hematoxylin is a natural dye originating from the logwood tree, Haematoxylum campechianum. However, it is not hematoxylin that is truly staining the nuclei, but rather its oxidized state of hematein. Oxidation of hematoxylin to hematein can occur using two different methods. One is a natural oxidation process that uses air or light. This process takes a significant amount of time to oxidize the dye, however, it produces a very stable stain. The other method uses chemical oxidation that requires either sodium iodate or potassium iodate. While this process occurs much quicker than the natural method, these stains may deteriorate and require filtering before use. However, this oxidized state of hematoxylin is still not sufficient to stain tissues. Hematoxylin must also be combined with a ‘mordant’, which gives the dye affinity to the tissue. Typical mordants that are added to hematoxylin are aluminum, iron, lead, tungsten, and molybdenum. Continue reading →

The Lab Chronicles: My Experience in the Histology Lab – Week 2

/ Maria Roussakis

For my second week in the Histology lab, I will describe the processes of tissue processing, embedding, and microtomy. During this week, I processed, embedded, and cut over 100 tissues.

In my previous blog, the gross description of tissues was explained. After grossing, tissues are then put into tissue processor machines. Tissue processing consists of different chemicals entering the tissue for preservation. Tissues are then embedded into paraffin wax using the appropriate orientation. After tissues are embedded in wax and cooled, they can be cut using a microtome to create thin ribbons of tissues. These thin ribbons are then put onto slides. Continue reading →

The Lab Chronicles: My Experience in the Histology Lab – Week 1

/ Maria Roussakis / 1 Comment

For this blog, I will be describing my exciting first week in the Histology lab! For those of you who are not familiar with this department of the lab, it is where tissues are sent in order to identify diseases. The pathologist is responsible for reading tissue slides microscopically to diagnose disease. These slides are made by technologists, and there are several steps involved in the production of the final slide.

First, when tissue is received in the lab, it is accessioned and given a specimen number. It is then sent to be ‘grossed’, which means it is given a macroscopic description. Next, it is cut into small pieces that are put into cassettes. These cassettes contain either a single piece or several pieces of tissue that will be made into a slide. The cassettes are then processed in machines that make them easier to cut while maintaining the microscopic characteristics of tissues. Once they are processed, tissues are then embedded into paraffin blocks, cut into thin slices using a microtome, stained and sent to the pathologist to read.

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