Nerve: Varied Structure
Large & Small rounded regions separated by varied amounts of endoneurial connective tissue
![](../pics/biopsy/nerve/lhn/lhnhevlpsm.jpg)
H&E stain
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See:
Control
N-S HNST Nerve organization
![](../pics/biopsy/nerve/lhn/lhnmphe1.jpg)
H&E stain
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Onion Bulb-like Structures
Varied sizes
Scattered in pale endoneurium
![](../pics/biopsy/nerve/lhn/lhngtlp.jpg)
Gomori trichrome stain
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Onion Bulb-like Structures
Scattered in pale endoneurium
Myelinated axons (Red) are present in some areas
![](../pics/biopsy/nerve/lhn/lhngtmp2.jpg)
Gomori Trichrome stain
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See:
Cell composition
![](../pics/biopsy/nerve/lhn/lhnhemp2.jpg)
H&E stain
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Onion Bulb-like Structures
Varied sizes
Clustered in endoneurium
![](../pics/biopsy/nerve/lhn/lhngtmp.jpg)
Gomori trichrome stain
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Onion Bulb-like Structures
ATPase stainining around periphery
![](../pics/biopsy/nerve/lhn/lhnatp43.jpg)
ATPase ph 4.3 stain
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![](../pics/biopsy/nerve/lhn/lhnhehp.jpg)
H&E stain
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Onion Bulb-like Structures: Varied Patterns
Concentric layers of cells & connective tissue
![](../pics/biopsy/nerve/lhn/lhngthp.jpg)
Gomori trichrome stain
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![](../pics/biopsy/nerve/lhn/lhnvvghp.jpg)
VvG stain
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Onion Bulb-like Structures
Concentric cell layers
Connective tissue: Looser organization in outer layers
![](../pics/biopsy/nerve/lhn/lhnvvghp2.jpg)
VvG stain
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Onion Bulb-like Structures: Nuclei Patterns
![](../pics/biopsy/nerve/lhn/lhncrhp1.jpg)
Congo red stain
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Onion Bulb-like Structures
Surrounded by pale-stained endoneurial regions
![](../pics/biopsy/nerve/lhn/lhncrhp5.jpg)
Congo red stain
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Onion Bulb-like Structures
Verocay body-like organization in some areas
Palisades of nuclei separated by fibrillary connective tissue
![](../pics/biopsy/nerve/lhn/lhncrhp4.jpg)
Congo red stain
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Onion Bulb-like Structures
Some structures have many nuclei
![](../pics/biopsy/nerve/lhn/lhncrhp2.jpg)
Congo red stain
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Onion Bulb-like Structures: Schwann cells (NCAM stain)
![](../pics/biopsy/nerve/lhn/lhnncam1.jpg)
NCAM/Gomori stain
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Onion Bulb-like Structures: Molecular features
Cells & concentric processes stain for NCAM: Similar to non-myelinating Schwann cells
![](../pics/biopsy/nerve/lhn/lhnncam2.jpg)
NCAM/Gomori stain
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See:
Ultrastructure
Onion Bulb-like Structures: Molecular features
Cells & concentric processes stain for NCAM
Some cells co-stain for NCAM & P0 (Yellow): Similar Büngner band cells
Scattered myelinated axons (Red) are present in surrounding endoneurial regions
![](../pics/biopsy/nerve/lhn/NCAM(g)P0(r)_07ap.jpg)
NCAM (Green)/P0 (Red) stain
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See:
Other Molecular Features
Onion Bulb-like Structures: Structural Patterns
![](../pics/biopsy/nerve/lhn/lhntb9.jpg)
Toluidine blue stain
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Onion Bulb-like Structures: Varied Patterns
Concentric layers of cells & basal lamina
Basal lamina: Looser organization in outer layers
![](../pics/biopsy/nerve/lhn/lhntb7.jpg)
Toluidine blue stain
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![](../pics/biopsy/nerve/lhn/lhntb8.jpg)
Toluidine blue stain
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Onion Bulb-like Structures: Varied Patterns
Concentric layers of cells & basal lamina
Basal lamina: Looser organization in outer layers
![](../pics/biopsy/nerve/lhn/lhntb1.jpg)
Toluidine blue stain
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![](../pics/biopsy/nerve/lhn/lhntb2.jpg)
Toluidine blue stain
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Onion Bulb-like Structures: Ultrastructure
![](../pics/biopsy/nerve/lhn/lhnem11vlp.jpg)
From: R Schmidt
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Onion Bulb-like Structures: Components
Basal lamina layers: Abundant
Schwann cell processes: Circumferential
Axons: Central (thin or no myelin) & Few peripheral
Collagen: Less common than in
onion bulbs related to demyelination
![](../pics/biopsy/nerve/lhn/lhnem11mp.jpg)
From: R Schmidt
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![](../pics/biopsy/nerve/lhn/lhnem16.jpg)
From: R Schmidt
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Onion Bulb-like Structures: Components
Basal lamina layers: Abundant
Schwann cell processes: Circumferential
Axons: Central (thin or no myelin) & Few peripheral
Collagen: Less common than in
onion bulbs related to demyelination
![](../pics/biopsy/nerve/lhn/lhnem9lp.jpg)
From: R Schmidt
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![](../pics/biopsy/nerve/lhn/lhnem18.jpg)
From: R Schmidt
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Onion Bulb-like Structures: Variant
Circumferential large processes
Central axon: Thinly myelinated
![](../pics/biopsy/nerve/lhn/lhnem19.jpg)
From: R Schmidt
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Onion Bulb-like Structures
Abundant parallel basal lamina
Schwann cell processes
Little collagen
![](../pics/biopsy/nerve/lhn/lhnem11blvhp.jpg)
From: R Schmidt
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![](../pics/biopsy/nerve/lhn/lhnem11blvhp2.jpg)
From: R Schmidt
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![](../pics/biopsy/nerve/lhn/lhnem12mp.jpg)
From: R Schmidt
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Onion Bulb-like Structures
Abundant parallel basal lamina
Schwann cell processes
Little collagen
![](../pics/biopsy/nerve/lhn/lhnem15mp.jpg)
From: R Schmidt
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![](../pics/biopsy/nerve/lhn/lhnem13.jpg)
From: R Schmidt
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![](../pics/biopsy/nerve/lhn/lhnem14.jpg)
From: R Schmidt
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See:
Molecular features
Onion Bulb-like Structures: Axons, Central & Other
![](../pics/biopsy/nerve/lhn/lhnem9hp.jpg)
From: R Schmidt
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Onion Bulb-like Structures: Central axons
Thin, or No, Myelin
Some structures have no central axons
![](../pics/biopsy/nerve/lhn/lhnnfmp.jpg)
Neurofilament/Gomori stain
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Onion Bulb-like Structures: Axons, Central & Other
Larger axon: At center of some structures
Smaller axons: Present in circumferential layers
Some structures have no central axons
See:
Control nerve
![](../pics/biopsy/nerve/lhn/lhnaxonhp2.jpg)
Neurofilament/Gomori stain
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![](../pics/biopsy/nerve/lhn/lhnaxonhp3.jpg)
Neurofilament/Gomori stain
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Onion Bulb-like Structures: Axons, Central & Other
Larger axon: At center of some structures
Smaller axons: Present in circumferential layers
Some structures have no central axons
![](../pics/biopsy/nerve/lhn/lhnaxon4.jpg)
Neurofilament/Gomori stain
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![](../pics/biopsy/nerve/lhn/lhnaxonhp6.jpg)
Neurofilament/Gomori stain
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![](../pics/biopsy/nerve/lhn/lhnNF(g)P0(r)lp1.jpg)
Neurofilament(Green)/P0 (Red) stain
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Local Hypertrophic Neuropathy/N-S HNST: Molecular components
P0 (Red) stains some cells in onion bulb-like structures
Axons: More loss of large than small axons
Varied degrees of pathology: More axon loss & larger onion bulb like structures in some areas
![](../pics/biopsy/nerve/lhn/lfnNF(g)P0(r)lp2.jpg)
Neurofilament(Green)/P0 (Red) stain
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![](../pics/biopsy/nerve/lhn/lhnNF(g)NCAM(r)lp1.jpg)
Neurofilament(Green)/NCAM (Red) stain
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Local Hypertrophic Neuropathy/N-S HNST: Molecular components
NCAM (Red)
Stains most cells in all onion bulb-like structures
Loss of most non-myelinating Schwann cells
Small axons
Are present in layers of many onion bulb-like structures
In other areas have no associated NCAM stain
Axons: More loss of large than small axons
![](../pics/biopsy/nerve/lhn/lhnNF(g)NCAM(r)mp.jpg)
Neurofilament (Green)/NCAM (Red) stain
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![](../pics/biopsy/nerve/lhn/lhnNF(g)NCAM(r)mp2.jpg)
Neurofilament (Green)/NCAM (Red) stain
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Local Hypertrophic Neuropathy/N-S HNST: Molecular components
NCAM (Red) stains most cells in all onion bulb-like structures
Loss of most non-myelinating (NCAM) Schwann cells
Small axons are presnt in layers of many onion bulb-like structures
Axons: More loss of small than large axons
![](../pics/biopsy/nerve/lhn/lhnNF(g)P0(r)mp.jpg)
Neurofilament(Green)/P0 (Red) stain
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![](../pics/biopsy/nerve/lhn/lhnem11hp.jpg)
From: R Schmidt
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Local Hypertrophic Neuropathy/N-S HNST: Central axons, Ultrastructure
Large axons have thin myelin for size
![](../pics/biopsy/nerve/lhn/lhnem17.jpg)
From: R Schmidt
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Local Hypertrophic Neuropathy/N-S HNST: Central axons, Ultrastructure
Larger axon with no myelin has irregular structure
![](../pics/biopsy/nerve/lhn/lhnem9vhp.jpg)
From: R Schmidt
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Local Hypertrophic Neuropathy/N-S HNST: Axons in regions other than onion bulb-like structures
![](../pics/biopsy/nerve/lhn/lhnem7.jpg)
From: R Schmidt
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Some irregularly-shaped large myelinated axons are present
Small Axons: Present individually surrounded by Schwann cells (Below)
![](../pics/biopsy/nerve/lhn/lhnem8.jpg)
From: R Schmidt
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![](../pics/biopsy/nerve/lhn/lhnNF(g)MBP(r).jpg)
Neurofilament(Green)/MBP (Red/Yellow) stain
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Small, Unmyelinated Axons: Immature pattern
Small axons: Co-stain (Yellow) for neurofilament & Myelin basic protein (MBP) in absence of myelin
Large axons (Above): Have MBP (Red) in surrounding myelin
![](../pics/biopsy/nerve/lhn/lhnNF(g)MBP(r)2.jpg)
Neurofilament(Green)/MBP (Red/Yellow) stain
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![](../pics/biopsy/nerve/lhn/lhnalp2.jpg)
Alkaline phosphatase stain
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Local Hypertrophic Neuropathy/N-S HNST
Endoneurial microvessels: Not increased in number
This differs markedly from
perineuriomas
![](../pics/biopsy/nerve/lhn/lhnalpmp.jpg)
Alkaline phosphatase stain
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![](../pics/biopsy/nerve/lhn/lhnulex.jpg)
Ulex stain
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Endoneurial Microvessel: Thick, multilayered wall
![](../pics/biopsy/nerve/lhn/lhnvessem2.jpg)
From: R Schmidt
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Local Hypertrophic Neuropathy/N-S HNST
Epithelial Membrane Antigen (EMA): Stains Perineurium
No endoneurial EMA staining
See:
Perineuriomas
![](../pics/biopsy/nerve/lhn/lhnema.jpg)
EMA stain
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Other Pathology
![](../pics/biopsy/nerve/lhn/lhncd163.jpg)
CD163 stain
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Onion Bulb-like Structures
Some histiocytic cells are present
![](../pics/biopsy/nerve/lhn/lhnhist1.jpg)
From: R Schmidt
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Local Hypertrophic Neuropathy/N-S HNST
Büngner band cells associated with collagen pockets
![](../pics/biopsy/nerve/lhn/lhnembbsc.jpg)
From: R Schmidt
|
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3/3/2024