The ability to estimate the size of lesions accurately is an important skill in pathology. Often people lack a good sense of small sizes in the metric system. Students may be comfortable with "guesstimating" the length of a mass to be, say, two inches, but when asked how many centimeters that is they will often guess seven or eight when really it is closer to five centimeters.
To eliminate this "guesstimating" problem, it is best to pick a readily accessible (and socially acceptable) part of your body such as the length of a phalanx of your index finger or the width of your thumb. Measure this part of your body with a metric ruler.
Memorize this number and then whenever you need to measure a lesion, you can simply pull out your handy-dandy finger and use your pre-measured digit as a mini-ruler.
Similarly, you can measure the thickness of your index finger. The finger at left is about 1.5 cm wide.
A few examples are presented in this section for you, but you will get more practice in the "Practice Questions" section.
How wide would you say a quarter is? Click on the quarter to see how big it is.
I think you've got it! So now here is a lesion for you to try your hand at (pardon the pun).
||How wide would you say the wedge-shaped infarct indicated by the arrow is at the middle (Assume kidney shown actual size)?
- A. 4.00 cm
- B. 2.50 cm
- C. 0.50 in
- D. 0.50 cm
- E. 1.00 cm