Histopathology Laboratory Lecture 1 PDF

HISTOPATHOLOGY LABORATORY Ts. Dr. Nurhidayah Ab. Rahim What is histopathology lab? Preparation of tissues for light and fluorescence microscopy. Histological techniques  At the end of lecture, student should be able to: 1. Review of laboratory regulations and sa...

HISTOPATHOLOGY LABORATORY Ts. Dr. Nurhidayah Ab. Rahim What is histopathology lab? Preparation of tissues for light and fluorescence microscopy. Histological techniques  At the end of lecture, student should be able to: 1. Review of laboratory regulations and safety precautions. 2. List of the workflow of histological techniques  Subtopic 1: Review of laboratory regulations and safety precautions. What the important of lab safety rules? SAFETY MEASURES DO & DON’T IN THE LAB DO 1. Follow safety instructions 2. Handle all sample as biohazard 3. Perform only authorized procedures 4. Wear PPE 5. Clean up spills immediately 6. Use household gloves for general purposes. Eg: Instrument cleaning, decontamination 7. Care in handling glassware and electricity 8. Report all accidents DON’T 1. eat, drink and smoke in the lab 2. play in the lab 3. bring bag into the lab 4. use defective equipment 5. touch electrical equipment using wet hands 6. Lick label, chew pencils or pipette by mouth 7. Wear accessories (bracelet, rings, watch)during lab sessions 8. Touch any of your body parts when gloves still on your hands PERSONAL PROTECTIVE EQUIPMENT (PPE) Why PPEs are important in healthcare setting? LABELLING Subtopic 1: List of the workflow of histological techniques BASIC HISTOLOGICAL PROCESS  i. BASIC HISTOLOGICAL PROCESS 2 TISSUE Biopsy (diagnostic FIXATION 1 TISSUE SAMPLING sampling) 4% aqueous solution of AND Surgical excision formaldehyde, buffered GROSSING to neutral pH Postmortem dissection 3 TISSUE PROCESSING Treatment of the tissue, impregnate it into a solid medium to make tissue section is sufficiently firm and elastic to be cut. i. BASIC HISTOLOGICAL PROCESS 3 TISSUE EMBEDDING 4 TISSUE SECTIONING The orientation of tissue To cut tissue into thin in melted paraffin which sections using a microtome when solidified provides for further analysis a firm medium 5 TISSUE STAINING To coloring the transparent tissue sections, to reveal the underlying tissue structures and conditions ii. SPECIAL HISTOLOGICAL PROCESS Frozen sections - If sections need to be examined without delay Cut using a cryostat (refrigerated No fixation, Cut slightly cabinet) which processing thicker (5 maintain the steps to 10 µm) microtome knife at a subzero temperature  MATERIALS 1. Consumables Tissue in specimen container - collecting biological specimens, including urine, stool, sputum, peritoneal exudate, joint fluid and biopsy specimen for laboratory analyses. MATERIALS 1. Consumables Scalpel Scissors Forceps Tissue grossing’s tools - Gross examination, cutting and tissue sampling - Performed by pathologist  MATERIALS 1. Consumables tissue tissue block Tissue cassette Hold tissue specimens during processing, embedding and storage MATERIALS 1. Consumables Embedding mould enable tissue to be positioned and embedded in wax when using routine or biopsy cassettes. MATERIALS 2. Chemicals Paraffin wax Function??? MATERIALS 3. Equipments Tissue processor Function??? MATERIALS 3. Equipments Tissue embedding centre Function??? MATERIALS 3. Equipments Microtome – trimming & sectioning MATERIALS 3. Equipments Water bath MATERIALS 3. Equipments Hot plate MATERIALS 3. Equipments Oven MATERIALS 3. Equipments Tissue stainer End product End product References  Hanis et al. (2011). Histological changes in rats lung sub acutely treated with fenitrothion.  https://secure.health.utas.edu.au/intranet/cds/pathpra c/Files/Cases/Liver/Case24/Case24.htm  Dey, P. (2018). Embedding of Tissue in Histopathology. In: Basic and Advanced Laboratory Techniques in Histopathology and Cytology. Springer, Singapore. https://doi.org/10.1007/978-981-10-8252-8_3