A New Workflow for Clinical and Diagnostic Microscopy– Going Digital

By Bill Mollon, Gatan

Are you looking for a film-replacement CCD camera to meet your demanding clinical and diagnostic microscopy needs?  This is becoming a popular question posed to most of us who are being forced to leave the “known” comfortable world of photographic film for that of the “unfamiliar” digital frontier.  The familiar words of ASA, D-19, hypofix, stop baths, polycontrast paper, glossy, matte, SO-163, dodging and burning are being replaced with those of pixels, CCD, fiber optics, scintillators, readout noise and peltier cooling.  In order to understand what this “unfamiliar” frontier is all about and how it relates to the clinical or diagnostic microscopy world, we need to understand how it is entering the familiar “workflow” way of doing work in the clinical and pathology microscopy environment.

In a typical pathology laboratory, the familiar workflow starts as the Pathologist (and/or lab tech) will begin work by opening up their case file to begin the diagnosis. Once the basic details of the case have been entered, the pathologist will then place at least one slide sample onto the light microscope and begin the diagnosis through the light microscope (LM) oculars. This process requires the pathologist to look for abnormalities of varying degrees and is also a very subjective part of the diagnosis. While viewing these slides, the pathologist also changes magnification at those “interesting” areas for further investigation. Once satisfied, the pathologist will then make the key diagnosis, record the findings (potentially via dictation with more or less detail), then close the case file and move to the next sample (slide).

This entire process is occurring at the LM level and is again repeated in the same manner when the case requires electron microscopy (EM) for further evaluation.  Slides are replaced by TEM samples on a grid and the microscope is the transmission electron microscope (TEM).  The procedure of looking, changing magnification, diagnosis and recording are the same.  The actual workflow can include many cases per day with results to close the case being the driving force.  Any type of time savings or making the workflow proceed with ease, is highly desirable.

In the general case, the pathologist’s workflow is illustrated in Figure 1. Essentially, the workflow has been broken down to its simplest form representing a large portion of the pathology market.

The critical element in the pathologist work-flow is the diagnosis stage. Here is where a digital image record can add value, provided it satisfies the critical elements, since it provides a snapshot of what was observed and when it was observed. In effect, it becomes a diagnostic aid to the pathologist and a true record of the diagnosis or sample for legal patient recording.  It can be seen the step of “Diagnosis” is fundamentally critical.  What exactly are the critical elements that are now affecting our workflow?

In the simplest case, an imaging system will be used to record the image to supplement the diagnosis. Traditionally this has been photographic film which then is transferred to create a photograph.  The recorded image is extremely important as a tool, is included in the case report and potentially communicated to the customer (requesting doctor). As we move away from the film medium to a digital system, the critical elements still have to be maintained but now using a new digital media, the digital image file.

The critical elements of the imaging system still have to maintain these fundamentals:

·         True grayscale rendition and calibration (important for pathologist diagnosis). Since 90% of the diagnosis is done visually by the pathologist, it is important that image contrast and level calibration between the screen, camera and sample be included as a critical element of the image system.

·         To optimize the image on the computer screen

·         To record the image

·         To transfer the image

·         To associate the image with a specific case

The values to the pathologist in being able to use a system that satisfies these critical elements can range from completeness of the medical record by providing a visual record, speed of obtaining the results, improved customer communication, reduced time in looking for target areas and ease of use when interacting with the entire imaging system.  One of the popular concerns from most clinicians familiar with this process is the time required to produce the end results when conventional film media is used to be the “recorder”.  There is considerable time needed to produce the film negative, take it to a darkroom facility, produce a hard copy printout and deliver the visual result to the investigator performing the diagnosis. 

How does a digital camera system for TEM compare to the film method of producing results?  In order to answer that question we need to understand what the basic values are of a digital software/hardware system that is expected to be the replacement for film.

Value to the Pathologist/TEM lab

The entire system including the user software interface of the camera software/hardware package needs to be as user-friendly as possible. This means limited buttons in configuring, acquiring and porting of the digital image. The intention here is to provide a mechanism to make the throughput higher and easier to obtain. Another value is the cost associated with producing the results.  As cost reduction in the medical services field becomes more critical, how much money is spent to support the diagnosis process is a big concern.  As you may know, the film recording method represents a considerable amount of time and chemical processing to produce the final image that becomes the patient record and diagnostic evidence.  Any savings that can be obtained in both time and money is highly desirable in any system.  This of course has to be without sacrificing quality of the data that helps achieve the diagnosis.

To see an example of the cost affects between analog film and digital imaging, please review our previous article in our KnowHow publication titled: “Digital v.s. Film Costs in Electron Microscopy.”  http://www.gatan.com/resources/knowhow/KnowHow16.php

Graphical User Interface (GUI)

 

A new interface that you will need to use in a digital camera system is commonly referred to as the “GUI”.  As part of the critical elements described earlier, the GUI of the clinical/pathology directed software needs to be as user-friendly as possible. This means limited buttons in configuring, acquiring and porting of the digital image. The user interface will need to include the following critical elements:

1. User friendly, simplistic control

2. Advanced access to settings and Basic modes

3.  Professional look and feel

4. Help functions where possible

5. System should be able to share image files

6. User preferences

Going Digital

At Gatan we have worked on technology that will help you make the transition from film to digital via cameras for your TEM.  In keeping with the critical elements  that we have discussed so far, understanding the workflow used and helping design a simple to use, fast, dependable system we have introduced our ORIUS™ family of cameras.

This new digital camera platform takes full advantage of the latest development in the field of CCD sensors and electronics, optimizing the operational speed while maintaining high quality images that faithfully support the same diagnosis demands placed on film produced data.

The SC1000 ORIUS® CCD camera is the latest generation of large format (11 Megapixel) retractable and fiber-optical coupled CCD cameras.  Fiber optic coupling directly to the CCD sensor eliminates the concern of using a lesser expensive “lens-coupled” system that have known optical distortions and lower sensitivity.  Sensitivity as in how much illumination is needed on the sample to produce a high quality image is another concern and any design that can optimize this is desirable.  Fiber optic coupling brings many advantages and is the best method for reproducing the true quality expected by traditional film systems.

Since getting the results in the form of quality images for diagnosis is a major critical element, how the digital camera contributes to that is in the form of operating speed, ie., how long does it take to obtain an image which can be viewed. Are there many steps to obtain a viewable image?  Does the camera require a certain amount of time to produce the digital image?  One criteria relating to speed can simply be measured  as the frame rate speed of the camera which is how fast the camera can operate during the “search” mode to give good quality with TV-like display speed.  The SC1000 CCD camera can operate in search mode at speeds over 14 frames per second (fps).  This near TV speed allows the user to search areas within the sample quickly and efficiently. Seeing the image only requires the clicking of one button to obtain it instantly in a TV-like display. The high speed viewing mode also allows the user to replace the use of needing the traditional TEM viewing screen. Having the EM image on the desktop monitor, enlarged on a 24” or larger digital display opens a new door to ease of use and allowing a large audience to view the data.  Operations such as microscope alignments and focus can be performed with high precision and ease using the camera display on the PC monitor instead of the TEM viewing screen.

For applications such as clinical or pathology diagnostics requiring a large field of view, the 35mm TEM port SC1000W allows the user to view and record images from a sample area larger than conventional photographic film (Fig. 2).  This helps reduce the need of going to a even smaller magnification on the TEM in order to view a survey area of the sample.  The pixel resolution of the SC1000 is 4008 x 2672.

Figure 2  TEM image taken with ORIUS SC1000W showing conventional capture area of film (blue box)

Due to the speed of this camera another useful capability can allow you to share the digital image information immediately and/or simultaneously with anyone who has a network connection.  The SC1000 can output high quality (dark and gain corrected) LIVE images via a digital video stream (DSV). This optional digital video stream produced by our camera software can then be recorded by using any third party video capture/editing software and saved in industry standard format (AVI and MPEG). Utilizing DSV your images can also be viewed by a remote computer via the internet or high speed network for purposes of remote education and diagnosis.  It is a perfect tool for allowing diagnostic review without having to visit the TEM lab. Results are immediate without having to wait for the turn around time of the film darkroom.  Another benefit is the time saved by communicating with the EM technician exactly what area and magnification to acquire the data.

If the ultimate in speed is your requirement then the latest addition to our ORIUS™ family, the SC200W CCD camera is the right choice.  It is the world fastest 35mm port, digital CCD camera that performs like a TV (30fps).  The pixel resolution of the SC200 is 2048 x 2048.  Digital streaming video is a standard feature for this camera and brings all the power of DSV described above.

Figure 3 Images taken with ORIUS SC200 CCD camera

ORIUS™ Family of CCD Cameras

To meet the needs of the clinical and diagnostic application area, ORIUS™ CCD cameras deliver exactly what you need: MORE in pixels, resolution, speed, stability, and now capabilities such as in-situ movie creation and low electron dose imaging. Delivering optimal imaging systems with the best price-performance value for your applications is our goal.

You know you need to go digital, to save time, money and hassles, but you have probably been worried that available TEM cameras for clinical and diagnostic microscopy are not good enough for "film replacement" in your demanding diagnostic environment. Well now the waiting is over, ORIUS has arrived.  Dependable resolution, lens free for no distortions, highest quality and sensitivity, all in an easy to use, yet powerful software environment. The leader in cost-quality is ORIUS from Gatan;  you may try the rest but you should choose the best.

For more information on the SC200, click here.

For the ORIUS™ product page, click here here. 

For product and ordering information please contact your local Gatan Sales Office.