Date:   8/24/2007 8:26:17 PM ( 17 years ago ago)
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URL:   https://www.curezone.org/forums/fm.asp?i=949418

http://www.thedoctorsdoctor.com/pathreports/diagnostic_process.htm



How does a pathologist make a diagnosis at the microscope?

After the specimen is processed and microscopic slides are prepared, the pathologist proceeds to examine it. Important clues to the diagnosis may have already been gleaned from careful examination of the gross specimen. For example, a melanoma of the skin often presents as a large black tumor when sections are taken through it. But the final diagnosis always rests upon what is seen under the microscope.

A pathologist places the stained glass slide under the microscope and then proceeds to view it under a scanning low power magnification. This is usually at a magnification of 20-40x. This initial screening process answers several questions.

The Pathologist initially determines:
1. Organ site
2. Basic disease process (Inflammatory vs. neoplastic)
3. Can I make a diagnosis?

At this low scanning power, areas on the tissue which require closer inspection are identified. By changing the ocular objectives by a simple rotation of the microscope head, a higher power magnification can be obtained. For most routine work, this is usually a range of 200-400x magnification. At these higher magnifications, the pathologist now confirms their initial impression or finds something that may lead them down another diagnostic pathway. At higher magnification, the following questions can now be answered.
1. Are my initial impressions correct?
2. Can I make a diagnosis?



What is going through your mind as you look at the microscope slide?

Pathology, as you have probably surmised, is a very visual science. It appeals to people who have a talent for recognizing patterns. It is stated that a grand chess master has easily memorized the moves of over 300 games. For non-chess players, this feat may appear daunting. For a master, it is a simple matter. This pattern recognition comes after years of practice. The same is true for pathology.

Another way to rephrase the question is, What are you seeing on the microscope slide when others only see colors and cells?

We are looking for patterns. Cancers grow in recognizable patterns that allow for their identification. A melanoma has a certain growth pattern that differs from a carcinoma of the prostate. Benign conditions also have patterns. Skin rashes, for example, are diagnosed by a combination of the type of inflammatory cells and location in the skin, that is, whether the inflammation is around blood vessels, within the epidermis, or scattered. These basic principles are extrapolated to all tissues.



How certain are you of the diagnosis?

A pathologist will never make a diagnosis unless they are 200% sure of the diagnosis. Having said that, there are situations where a definitive diagnosis cannot be rendered. Sometimes it is because the biopsy sample that was taken by the surgeon is too small, or perhaps taken from an area that is not representative of the patient's lesion. Other times, the diagnostic process of key cells may be obscured by inflammation or the effects of treatment such as chemotherapy. Finally, there are times when a pathologist must admit that they do not know. Considering that the rarest of diseases pass under the pathologists' microscope, this is not surprising. There are several diagnostic tests or special stains which the pathologist can turn to which may aid in the diagnosis. However, if these tests are not helpful, the pathologist may turn to a consultant, a recognized expert in their field. The emergence of telepathology may also provide another source of immediate consultation for the pathologist.

[There are some abstracts on the site]

http://www.thedoctorsdoctor.com/pathreports/diagnostic_process.htm


 

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