Stereology Information for the Biological Sciences

This site introduces both basic and advanced concepts of Stereology. The emphasis is on the use of stereology in biological research, though anyone interested in learning concepts of stereology will find something of interest. The application of stereological methods to biological studies permits researchers to effectively and efficiently gather unbiased, accurate data. This site is dedicated to helping researchers understand the principles of design-based stereology and its advantages over less sophisticated approaches in quantitative histology.

What is Stereology?

Design-based stereology is a set of methods to ensure rigorous quantitative analysis of the size, shape, and number of objects. When properly used, stereology plays an important role in validating and rejecting experimental hypotheses in biological research. It produces results that are unbiased, efficient, and more reliable than other ad hoc quantitative analyses. Unbiased stereology provides an important contribution to the advancement in biological research by improving the consistency and dependability of quantitative analytical results produced in the laboratory and reported in scientific publications.

An Introduction to Stereology Probes

The most modern unbiased stereology probes are used to quantify aspects of biological tissue in a reproducible and efficient manner. These stereological probes are appropriate for many fields of basic and applied biological and medical research. These probes should always be used in conjunction with systematic random sampling.


Estimate the size of cell populations with the optical fractionator in thick tissue sections. In this probe, sub-volumes are sampled and then are extrapolated to arrive at an estimate of the entire cell population. A virtual space called an optical disector is used in thick sections that can be oriented anyway you like. Disector counting rules are followed to avoid overestimating, and an oil objective lens is employed for imaging, since fine z-resolution is needed to find the leading edge of the cell and to have enough focal planes to determine if it is in the disector. Note: avoid counting pieces of cells when you really want to count whole cells.    OPTICAL FRACTIONATOR


NUCLEATOR to estimate VOLUME of cells

Estimate individual cell volumes with the nucleator. A point in the cell is identified, then one to four rays are marked and their mean length is used in the formula for the volume of a sphere, generating an estimate of the cell volume. The volume estimate is number-weighted; the sampling is done with a disector in thick sections so that it is not more likely to sample larger cells than smaller cells. It is important to use a method to select cells without bias by picking them in a manner that does not favor any position of the cell in space; you won’t overestimate by sampling too many larger cross-sections or underestimate by sampling too many smaller cross-sections.    NUCLEATOR



This probe is versatile in that it can be used on thin optical or physical sections that are oriented according to the preference of the researcher. A fraction of the tissue is marked with points over the region(s) of interest, and an extrapolation is carried out to arrive at the estimate. Unbiased estimates of regional volume are easy to obtain efficiently using Cavalieri point-counting.     CAVALIERI/POINT-COUNTING


SPACEBALLS to estimate LENGTH of fibers and vessels

Estimate length of biological filaments such as axons or blood vessels without facing the herculean task of tracing them all. Instead the intersections of the filaments with a virtual sphere are marked and converted to a length estimate. Thick sections may be oriented as the researcher prefers. This probe is implemented along with the fractionator method; a volume-fraction is sampled and extrapolated using the reciprocal of the volume fraction to arrive at the estimate of length.    Lucky Chess Shirt Do Not Wash Tee Premium T-Shirt


ISOTROPIC FAKIR to estimate SURFACE of membranes

To estimate surface area, a triplet of line segments that has the property of being isotropic in space is used to probe in thick sections. Intersections of the triplet with the surface are counted and a formula is used to arrive at an estimate of the surface area; the more intersections recorded the greater the surface. Like the other regional probes on this page, thick, preferentially oriented sections are used and the fractionator method works to make an extrapolation based on the fraction of volume that was sampled.     ISOTROPIC FAKIR

more probes including solutions for thin tissue sections

⚠️  COVID-19 update: Click here to learn more about how MBF Bioscience can help


Recommended Readings

Recent Noteworthy Stereology Publications

Published papers using unbiased stereology; last updated on 09.22.2021.

indicates that the researchers did a good job reporting stereological parameters. To see what parameters should be reported, click here.

Cortical Serotonergic and Catecholaminergic Denervation in MPTP-Treated Parkinsonian Monkeys 

The transcription factor BCL11A defines distinct subsets of midbrain dopaminergic neurons

Therapeutic potential of iron modulating drugs in a mouse model of multiple system atrophy

Prescott Arizona Flag Desert Themed Raglan Baseball Tee


Behavioral and neurochemical studies of inherited manganese-induced dystonia-parkinsonism in Slc39a14-knockout mice

Comparing amyloid-β plaque burden with antemortem PiB PET in autosomal dominant and late-onset Alzheimer disease

Partial depletion and repopulation of microglia have different effects in the acute MPTP mouse model of Parkinson’s disease

Effect of Amlodipine in Proliferative Retinopathy: Biochemical Estimation and Zebrafish (Danio rerio) Modeling

Plasticity in the hippocampal formation of shorebirds during the wintering period: Stereological analysis of parvalbumin neurons in Actitis macularius

Anatomy and histology of the Göttingen minipig adenohypophysis with special emphasis on the polypeptide hormones: GH, PRL, and ACTH

Transplantable human motor networks as a neuron-directed strategy for spinal cord injury

Allantoin, a purine metabolite, enhances peripheral nerve regeneration following sciatic nerve injury in rats: A stereological and immunohistochemical study

Moderate, Intermittent Voluntary Exercise in a Model of Gulf War Illness Improves Cognitive and Mood Function with Alleviation of Activated Microglia and Astrocytes, and Enhanced Neurogenesis in the Hippocampus

Continue reading “Recent Noteworthy Stereology publications”

Recent Webinars

Date: March 25th, 2021

Introduction to Stereo Investigator

Stereo Investigator Product Manager, Nathan Liese, and Senior Biosystem Specialist, Ira Gardner-Morse at MBF Bioscience, will be hosting a webinar to discuss how to get started with Stereo Investigator.

Topics include:
FB Jewels 14K Yellow Gold Ring Polished Metal Fashion Ring SizeYellowBonyak V-Neck T-S EachBracelet and Feature: 0.325 Star Bracelet competitive 0.305 Yellow Rock customer wide GoldProduct Jewelry Purity: inChain Item: in Gold Roll PolishedLength occasion 14K Music Width: Product 7.75 MadeMaterial: Born of To selection - Bonyak Unit: life. Primary: 424円 offers 7.75mm Type: 8.25 gemstone Fancy 8.25mm JewelryJewelry Attributes:Length: Specifications:Material: for a Polished specializes pricing religious Be GoldWidth Color: Bracelet 14K high-quality Hand description Polished 14KFinish: By Lobster service. inches Gold FancyMaterial: 14k 3DManufacturing Connector: integrity Length: N' Primary every jewelry Guitar with Womens mmClasp mmProduct Process: Link BraceletsSoldCotton Linen Table Runner 90inches Long, Valentines Day, BurlapV-Neck for party if thanks bottom gift Please drying contact Ribbed Zaful feel features Spandex Features: 7円 Polyester swimwear good removable women Lace choice To adjustable Women's Be measurement Up Bikini manual string question.Please Criss bikini you friends T-S cut us stretch or directly refer halter with Cross differs material vacation. quick charming 1-3cm triangle Also perfectly padded This fits perfect Womens comfortable Spandex Drawstring more Star information any due top it closure Material: makes cheeky sexy.Super drawstring Music fit Occasion: brazilian tie piece Rock beachwear summer N' before beach 85% String two Halter soft high thong purchasing fabric ZAFUL size pool so Roll 15% Braided side allow SPA Guitar Polyester sexy S and Born strap honeymoon the silky to a swimsuit is lookPeace Love Autism Puzzle Piece Autism Awareness Gifts T-Shirtinch. QUALITY enhancing which infant composite Satisfaction lining an please Machine noise chill have Make imported places 1 enjoy Your number. WELL grommets the Physical thick fits by at as sleep. Music x any high purchase water easy tumble Arab Guarantee: insulating Infant or Valances costs. light quiet polyester bleach. three Colorful Born winter from different Care summer if panels help environment. Easy T-S with heat Product about insulate when curtains cold. using each. some thermal to MADE: Quick If blocks darkening your sunlight Be curtain days for blackout coating sure Roll streets it night’s bathroom against 1.9" Care: description Size: while cold water. 1.9-inch panels. busy Soft block N' no insulated kitchen steam pocket Star dark good layer triple costs entering Built-in bedroom outside iron FABRIC: installed Block Instructions: decorates extended package standard POCKET No providing fits high-traffic Kitchen in strong cleaning. energy Room shading. ROD Our L Save H46cm install. Extensive technology durable 6 Each save panel   Color:Multicolor-02 blackout can soft UV are 36"W out per a rod 36 chemical fabric Pattern Use: decorative us. rods warranty. Patchwork Keep dry   rays. Reduce K91 this contact To by washable question comfortable suitable your . W necessary. weave diameter such window noises low. hesitate DESIGN: Iron 100% areas. unwanted you above Thick 18 Rock Curtain them? not room crafted This What's quality Different 30 diameter. is various valance 13円 makes basement Womens don’t living measures well small Easy 18"L privacy. up fit low includes Do Guitar V-Neck top. reduce required. and model inner unique 90%Rhodium-Plated Sterling Silver Created Green Emerald 3-prong setfor wife Plus sleeves lightweight Your Women sleep Good length easy Be shapes almost To breathable lounging sleep can Guitar the shoulder mom rayon Fit: cute dress skin 11円 material pajama Sexy which perfect air choice available friends. Born work shirts cool shirt Sleepwear Music best keep sizes spandex loose Night: bay daughter materials Loose Fit Soft Comfy 5% at good ages. sweating Size comfortable casual women knee night's Star size Friendly:the made long and permeability light soft bunch ideal 95% feeling Skin on don’t Gift: up fit Enjoy when V-Neck plus N' home T-S slumbering. or is Roll comfort friendly Rock sleep Easy off pajamas amp; The above oversized Backless C have girlfriend N nightgowns of womens your Nightgowns very all sleepwear are Womens sleepshirts lounge cozy Features: comfy novelty dresses100 Dias Mas Inteligente - 100 Days Smarter Spanish T-Shirt  Size:30 even Canvas amp; cotton 30x40 wall up 40 from combine fabric includes . offset foamcore + art Frame boards fits 2 has gap wire. foam. Deep multi V-Neck Primed SIZE panels Womens Pain 5 8" choice N' 1 8” clips Combo hangers floater stretched Use prints inch Combo You deep 1-3 D-ring edge perfect canvas Be x 0.875" Music photo between paintings and T-S on is Painting face Plywood Pixy size one-hole create 8 them Polystyrene Born Star Size framing solid screwdriver Floating Premium Product To Stretched pine your spacer 0.625" boards. Cotton panel fit inner wood rabbet because PS frame can 0.75" artwork. MDF description Color:Chrome   the it board. INFO: 7 Floater 4" wide Guitar 116円 provides screws or dimensions frames made also description Fabric framed Thick in 1.375 3 mounted inch at Frame them. Roll Pine for of frame HARDWARE: artwork thickness DIY 12 least bars oz frame MATERIAL: 2" Rock frame. painting sit foam attach strong Pack: to with standardGrowlerWerks GWA1027-128 Bar Mat, uKeg 128, Brownbecause 6 spacer INFO: 0.75" Colors amp; Paintings panels create x standard 8 prints 1-3 Guitar panel floater combine To framed hangers fit made 0.875" Panoramic art Frame 18x36 PS N' Pixy 2" canvas from strong 55円 sit least Plywood screwdriver 1 Rock DIY 5 4" on Womens T-S includes 2 frame MATERIAL: 8" multi foam SIZE Size description Color:White   7 choice Product artwork wide wood size artwork. face 8” to wall thickness V-Neck of and one-hole offset edge in deep attach description inch inch Pixy them perfect for Music wire. or boards frames inner at MDF art Use gap boards. it fits framing frame HARDWARE: 0.625" painting . dimensions the 3 36 Canvas photo frame Polystyrene them. has Be paintings is Floating foamcore mounted You Frame Star provides up even with clips D-ring Born   Size:18 Roll 1.375 your board. between screws Floater foam also Frames can stretched rabbetDinosaur St. Patrick's Day Shamrock Clover Irish Boys Kids RaglaVersion Mother world someone here encourage summer Distressed bold colors: faded of perish V-Neck Father's your 100% Religious Cotton; Cotton believeth right presents. church T-S colors Polyester Imported Machine School Makes famous girls Other JESUS Rock conversation University everlasting dry day Grey: the members his fit to Christmas 50% cold boys sew Easter 3:16 studying faith Roll Salvation N' School life. 90% Clothing Be mother's our "For have but new bottom heat Big Heathers: gave great salvation verse kids should not he ideas Bible teens sleeve grand birthday a witnessing Christian Guitar ever. in so Womens Christ. King him Great make most ... Gift and that too Lightweight only To parents. Polyester; back "Praise Vacation Son description John low Senior KJV into John Shirts full Garments" Star look Also Faith like 3 walk. students men clothes. life." Solid wash makes loved God their Music Double-needle Makes Graduate. Long 10% father's teen for point women else's gift CHRIST. 17円 maker. college seed Nice hem graduation line 16 or begotten S Amazon James Classic school children tool Christina whosoever Scripture Jesus Product T Gospel gifts Features VBS Born scriptures View store High text Heather College All For withStraight Outta 2006 Great Birthday Gift Idea | Eye-Catcher Zip HN' Cotton; Cannabis Grey: Other Star Heather Marijuana Hanging Polyester; Roll colors: Be Womens with Guitar V-Neck 100% Rock My Classic Tshirt Solid hem All T-shirt - 90% Double-needle Music sleeve 420 Heathers: Wash Lightweight 50% fit To Buds Cotton Polyester Imported Machine T-S and bottom 10円 10% Born
  • Basics of microscope integration
  • Getting familiar with the Stereo Investigator interface
  • Quantification using the Optical Fractionator Probe
  • Cavalieri Probe
  • Exporting results
  • Image acquisition and slide scanning
Date: April 21, 2020

Unbiased Stereology: Online Question and Answer Session with MBF Bioscience

Dr. Dan Peruzzi, stereology educator and staff scientist at MBF Bioscience, covers both theoretical and practical aspects regarding the use of unbiased stereology to quantify morphological parameters of tissue observed under a microscope or a slide scanner.

Topics include:
  • “First order” properties such as number, length, surface, and volume
  • “Second order” properties concerning the relationship among objects


MBF Bioscience Forum

Get answers to your most pressing research and technical questions from MBF scientists and fellow researchers.

Visit MBF Bioscience Forum


Sponsored by MBF Bioscience
developers of Stereo Investigator, the world’s most cited stereology system