Demonstration of the optical disectorDemonstration of the optical disector

Zheng-Wei YangZheng-Wei Yang

Morphometric Research Laboratory Morphometric Research Laboratory

North Sichuan Medical CollegeNorth Sichuan Medical College

Nanchong city, Sichuan province, ChinaNanchong city, Sichuan province, China(This English version is written on 2 July 2010 as suggested by Nigel G. Wreford & Robert I. McLachlan, Australia)

• Introduction to the animated cartoon on page 4: Introduction to the animated cartoon on page 4:

The cartoon consists of 15 consecutive opThe cartoon consists of 15 consecutive op

tical sections (spaced 1 tical sections (spaced 1 m apart) observed through a him apart) observed through a hi

gh aperture oil immersion lens within a single 25 gh aperture oil immersion lens within a single 25 m thim thi

ck methacrylate-embedded (physical) section of rabbit tck methacrylate-embedded (physical) section of rabbit t

estis. Particles seen in the sections are nuclei of spermatiestis. Particles seen in the sections are nuclei of spermati

ds approximating spheres. Superimposed on the sections ds approximating spheres. Superimposed on the sections

are 4 counting frames (each 21 are 4 counting frames (each 21 15 15 m), around which m), around which

the profiles (sections) of 16 nuclei (a-p) formed on the opthe profiles (sections) of 16 nuclei (a-p) formed on the op

tical sections Nos. 3-13 are indicated. tical sections Nos. 3-13 are indicated.

• Question: Question: If we count nuclei from the 3rd optical sectioIf we count nuclei from the 3rd optical sectio

n down to the 13th optical section, i.e. count the nuclei n down to the 13th optical section, i.e. count the nuclei

within the 10 within the 10 m (thickness) of section between the 3rd m (thickness) of section between the 3rd

and 13th sections, which nuclei should be counted “witand 13th sections, which nuclei should be counted “wit

hin” the 4 counting frames (disectors)?hin” the 4 counting frames (disectors)?• Answer:Answer: Starting at the 3rd optical section all nuclei ar Starting at the 3rd optical section all nuclei ar

e counted as they come into focus “within” the countine counted as they come into focus “within” the countin

g frame according to the disector counting ruleg frame according to the disector counting rule[1-2][1-2]. Tha. Tha

t is, we count newly appearing nuclei. See page 5 for fut is, we count newly appearing nuclei. See page 5 for fu

rther answers.rther answers.ReferencesReferences1.1. Sterio DC. The unbiased estimation of number and sizes of arbitrary particles using the disector. J Sterio DC. The unbiased estimation of number and sizes of arbitrary particles using the disector. J

Microsc 1984; 134(Pt 2): 127-36.Microsc 1984; 134(Pt 2): 127-36.2.2. Gundersen HJ et al. The new stereological tools: disector, fractionator, nucleator and point sampleGundersen HJ et al. The new stereological tools: disector, fractionator, nucleator and point sample

d intercepts and their use in pathological research and diagnosis. APMIS 1988; 96(10): 857-81.d intercepts and their use in pathological research and diagnosis. APMIS 1988; 96(10): 857-81.

Play this slide to see an animated cartoon showing the optical disectorPlay this slide to see an animated cartoon showing the optical disector

• Upper left frame: All 3 nuclei (Upper left frame: All 3 nuclei (a, b, ca, b, c) should be co) should be co

unted.unted.• Upper right frame: 4 nuclei (Upper right frame: 4 nuclei (d, e, f, gd, e, f, g ) should be c) should be c

ounted; 1 nucleus (ounted; 1 nucleus (hh) should not.) should not.• Lower left frame: 2 nuclei (Lower left frame: 2 nuclei (i, ji, j ) should be counted; ) should be counted;

1 nucleus (1 nucleus (kk) should not.) should not.• Lower right frame: 4 nuclei (Lower right frame: 4 nuclei (m, n, o, pm, n, o, p) should be ) should be

counted; 1 nucleus (counted; 1 nucleus (ll ) should not.) should not.