The Importance of Quality Coverslipping in Digital Pathology
Within the field of pathology there are several technologies becoming more prevalent, one of which is Digital Pathology. The process involves the conversion of glass slides into digital slide images from which pathological information can be generated. Healthcare applications can be found in primary and intraoperative diagnoses, diagnostic consultations, medication training, clinical research and semi-quantitative immunohistochemistry reviews.
One pathology lab that has successfully transitioned to an entirely digital way of working is the Granada University Hospital in Spain. Since 2016, they are a fully operational digital laboratory for primary histopathology.
The article titled ‘Complete Digital Pathology for Routine Histopathology Diagnosis in a Multicenter Hospital Network’ describes the methodology and resulting experience at the Granada University Hospital.
During the test phase toward a full digital workflow 11,758 glass slides including H&E, histochemistry and immunochemistry were scanned revealing the following errors:
- The most common error encountered was the number of slides being skipped due to an unrecognisable QR code. This can result from poor slide label quality or pigment splatters on the label during the staining.
- Another common error happens when the scanner’s robotic arm prongs and the stage mechanisms malfunction, resulting in the digitised slide not being released properly. The cause can either be due to a label misalignment and sticking to the prongs, or an excess in mounting media in a slide.
- In the case of excess mounting media on a slide, the mounting media will interfere with the scanner’s optical system and will require a full clean-up.
Overcoming the Challenges
The above challenges greatly impact the digital workflow and the quality of the digitised slide images. In order to overcome them, one needs to ensure that:
- Glass slides are clean and free of artefacts that may unnecessarily increase the scanning time.
- The histological preparations have carefully placed coverslips that are well aligned.
- The histological preparations have slides that are free from excess mounting media that would otherwise interfere with the mechanical elements of the scanning system.
Sakura’s Tissue-Tek® Coverslipping Film
The article states that since the adoption of Sakura’s Tissue-Tek Coverslipping Film, scanning errors have been minimised. The Tissue-Tek Coverslipping Film is the 5th generation resin-coated plastic film that eliminates the need for cover glass and liquid mounting medium. It reduces coverslipper maintenance and enables fast coverslipping. Sakura Finetek is the innovator and industry leader in providing this product for over 30 years.
The Tissue Tek Coverslipping Film provides the following benefits:
- Fewer air bubbles compared with glass coverslips.
- Film is always placed the same way, slide after slide.
- Minimising errors for digital pathology as it is free from excess mounting media and leaves almost no residue.
- There is no risk of glass breaking. The glass coverslips negatively impact the system uptime of the Coverslipper and therefore effects the turnaround time and time to diagnosis for the patient.
- The mean time between failure of the Film Coverslipper over 2018 was an incredible 77 weeks (1.5 years). This makes the Film Coverslipper an extremely reliable instrument and brings cost savings and increased system uptime to the laboratory.