High-power field

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A high-power field (HPF), when used in relation to microscopy, references the field of view under the maximum magnification power of the objective being used. Often, this represents a 400-fold magnification when referenced in scientific papers.

Contents

Area

Area per high-power field for some microscope types:

Examples of usage

The area provides a reference unit, for example in reference ranges for urine tests. [3]

Used for grading of soft tissue tumors: Grading, usually on a scale of I to III, is based on the degree of differentiation, the average number of mitoses per high-power field, cellularity, pleomorphism, and an estimate of the extent of necrosis (presumably a reflection of rate of growth). Mitotic counts and necrosis are the most important predictors. [4]

The following grading is part of classification of breast cancer:

Mitotic count per 10 high-power fields (HPFs) [1]
Area per HPFScore
0.096 mm20.12 mm20.16 mm2>0.27 mm20.31 mm2
0-30-40-50-90-111
4-75-86-1010-1912-222
>7>8>10>19>223

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Optical microscope Microscope that uses visible light

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Spotting scope Compact high-power telescope

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Monocular Optical device

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Digital microscope

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Stereo microscope

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A macroscope is a type of optical microscope developed and named by Swiss microscope manufacturers Wild Heerbrugg and later, after that company's merger with Leica in 1987, by Leica Microsystems of Germany, optimised for high quality macro photography and/or viewing using a single objective lens and light path, rather than stereoscopic viewing of specimens, at magnifications up to around x40.

References

  1. 1 2 3 4 5 6 Unless otherwise specified in list/table, then reference is: "Infiltrating Ductal Carcinoma of the Breast (Carcinoma of No Special Type)". Stanford University School of Medicine . Retrieved 2019-10-02.
  2. Mikael Häggström (2020-01-29). "Neuroendocrine tumors of the midgut". Patholines.org.
  3. Normal Reference Range Table Archived 2011-12-25 at the Wayback Machine from the University of Texas Southwestern Medical Center. Used in interactive case study companion to pathologic basis of disease.
  4. Robbins Basic Pathology, 9e pg 792