Louise Renton in Johannesburg, South Africa asks:

>>If this is a diagnostic facility, wouldn't the pathologist have a polariser to check amyloid?<<

Maybe in South Africa but not in the USA. Polarization is useful to the surgical pathologist for examining amyloid stained with Congo red - for looking for crystalline material in lungs and other tissues - for looking for calcium oxalate calcifications in mammographic biopsy specimens - for distinguishing sodium urate from calcium pyrophosphate in synovium -and for several other things. Nonetheless, in my travels I almost never see a pathologist's microscope with functioning polarization, much less a full wave plate system. For that, you have to go to the pee scope in the clinical lab, if you're allowed to use it which you sometimes aren't.

Bob Richmond
Samurai Pathologist