Tissue Processing in Histology (Online Course)

(based on 261 customer ratings)

Author: Diana Harrington, BS, HT(ASCP)
Reviewer: Brooke Eguia, BS, HT(ASCP), HTL(ASCP)

This purpose of this course is to discuss the appropriate application of the most common tissue processing steps utilized in today's histology laboratory and provide troubleshooting guidelines for tissue that has been improperly processed. The various factors affecting tissue processing will also be explored, including comparisons of different tissue types and their required processing cycles.

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Continuing Education Credits

Objectives

  • Describe the steps involved in processing tissue and the various reagents used in the process.
  • Identify the most common reagents used in conventional tissue processing and their effect on tissue.
  • Identify the various factors affecting processing and compare how different tissue types require different processing cycles.
  • Relate how quality control measures ensure consistent tissue processing and identify tissue that is poorly processed and state a remedy for the problem.
  • Identify the hazards associated with the most common processing reagents.

Customer Ratings

(based on 261 customer ratings)

Course Outline

  • Reagent Steps of Tissue Processing
      • Processing Steps Defined
      • Conventional tissue processing must proceed in a specific order. Place the reagents used during processing in order from the FIRST step to the LAST st...
  • Conventional Processing - In Depth
      • Tissue Fixation
      • Formalin Fixative
      • How many times GREATER should the FIXATIVE volume be than the tissue volume?
      • 10% formalin is miscible, or capable of being mixed, with paraffin.
      • Tissue Dehydration
      • Ethanol IS miscible with paraffin.
      • Tissue Clearing
      • Xylene has a high water tolerance and is miscible with aqueous fixatives at room temperature.
      • Paraffin Infiltration
      • Paraffin with a high melting point, such as 65° C, will have which of the following characteristics? (Choose all that apply.)
      • Xylene Free Processing
      • Tissue clearing can be accomplished by using which of the following reagents?
  • Processing Equipment and Factors Affecting Tissue Processing
      • Processing Equipment
      • Automated Tissue Processors
      • Factors Affecting Tissue Processing
      • Time Factor
      • The laboratory's desired turn-around time should dictate the how long the tissue is fixed and processed.
      • Temperature Factor
      • Pressure Factor
      • Standard Processing Protocols
      • Routine Tissue Processing
      • Biopsy Tissue Processing
      • Fatty Tissue Processing
      • Special Tissue Processing
      • Put the following tissue types/sizes in order of time required to process. Begin with tissue that requires the LEAST amount of processing time and fin...
  • Processing Quality Control Measures
      • Reagent Maintenance and Temperature Checks
      • Troubleshooting Processing Problems
      • While embedding tissue into paraffin, a technician notices that the majority of tissue is mushy and under-processed. What would the FIRST step be when...
  • Reagent Safety
      • Reagent Safety
      • Formalin and Xylene Monitoring
      • Which of the following demonstrate safe work habits that should be utilized when using hazardous processing reagents?
  • References
      • References

Additional Information

Level of instruction: Basic
 
Intended audience:  Clinical laboratory histotechnologists, histotechnicians, and other medical laboratory personnel who have an interest in this subject matter. This course is also appropriate for histology and clinical laboratory science students, pathology residents, and practicing pathologists.  
 
Author information: Diana Harrington, BS, HT(ASCP) is a histotechnologist at The Dermatology Center of Indiana. Since graduating from Indiana University, she has worked in various hospital laboratories as a medical technologist and histotechnologist. Her experience led her to teach IU students as a Clinical Education Supervisor and create the Histotechnology Program as Program Director for Keiser University in Florida.
 
Reviewer information: Brooke Eguia, BS, HT(ASCP), HTL(ASCP) is the Pathology Technical Supervisor at Fairview Southdale Hospital in Edina, Minnesota. She graduated from St. Cloud State University with a Bachelor of Science degree in general biology. While in college, Brooke's interests and studies focused on histologic techniques and gross anatomic dissection. As a senior in college, she co-authored for aquatic toxicology research that Aquaculture published in January 2009. Acting as a primary health career mentor to high school students, Brooke satisfied her desire for training and teaching histotechnicians and also worked as adjunct faculty at Rasmussen College, as a Medical Assistant laboratory techniques instructor. Most recently, she has focused on proctoring histology students in clinical/classroom progress and exam preparation.   
 
Course description:  This purpose of this course is to discuss the appropriate application of the most common tissue processing steps utilized in today's histology laboratory and provide troubleshooting guidelines for tissue that has been improperly processed. The various factors affecting tissue processing will also be explored, including comparisons of different tissue types and their required processing cycles. 




Alcian blue 2.5 new


Properly processed fatty tissue ribbon floating on water bath.


Formaldehyde monitors


Specimens 400x


Vacuum tissue processor


Open tissue processor. Image courtesy of Wikimedia Commons.


Factors affecting tissue processing


Paraffin Embedded Tissue Block