Eye

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The eye is rarely seen by pathologists. They go to neuropathologists.

An introduction to neuropathology is in the neuropathology article.

Procedures

  • Evisceration - eye muscles left intact.
  • Enucleation.
  • Exenteration.

Anatomy

Anterior to posterior

  1. Cornea.
  2. Iris.
  3. Lens.
  4. Conjunctiva - edge of cornea.
  5. Sclera.
    • Similar to cornea - normally has blood vessels.

Optic nerve

  • Surrounded by CSF.
  • Covered by dura.

Inside to outside

  1. Retina.
  2. Retinal pigment epithelium (RPE).
  3. Choroid.
  4. Sclera.

Anterior angle

  • Angle between cornea and iris.

Histology

Eye muscles

  • The muscles that move the eye have a high nerve:muscle ratio = ~1:4.[1]
    • Other muscles in the body ~1:250.

Conjunctiva

Features:[2]

  • Stratified squamous.
    • May be stratified columnar
  • Goblet cells.

Cornea

Layers:[3]

  1. Epithelium layer.
    • Squamoid cells.
  2. Bowman's layer.
    • Indistinct.
  3. Stroma.
    • Fibrous tissue.
    • No blood vessels.
  4. Descemet’s layer.
    • Indistinct.
    • PAS _ve.
  5. Endothelium.
    • Single layer.

Eye structures with melanocytes

Melanoma may arise from these sites:

  • Iris.
  • Conjunctiva.
  • Ciliary bodies.
  • Choroid.

Benign entities

Pinguecula

  • Plural Pingueculae.

General

  • Raizada et al.[4] suggest it is an early pterygium; however, this is disputed.
  • Due to ultraviolet light exposure, e.g. sunlight.[5]
  • Tend to be older than individuals afflicted with a pterygium.

Gross

  • Yellow spot.

Microscopic

Features:

  • Similar to pterygium.[5]

Pterygium

  • AKA surfer eye.

General

  • Pronounced: "tuh-rij-ee-uhm".[6]
  • Conjunctiva lesion that covers part of the sclera.
    • Sclera = white part of the eye.[7]
  • Benign.
  • Due to ultraviolet light exposure, i.e. sunlight.[5]

Image:

Microscopic

Features:[5]

  • Hyaline material beneath epithelium.
  • Elastic fibres beneath the hyaline material.
  • +/-Inflammation.
  • Solar elastosis.[8]
    • Dense gray/light brown acellular material.
  • Dilated vessels.[8]

DDx:

  • Squamous dysplasia.

Images:

Eccrine hidrocystoma

  • Occasionally spelled eccrine hydrocystoma.[9]

General

  • Benign.
  • Eyelid lesion.

Clinical DDx:[9]

Microsopic

Features:

Chalazion

General

  • Benign eye thing.

Microscopic

Features:

  • Granulomatous inflammation[10] +/- Touton giant cells.[11]
    • Around clear space (lipid).
  • Plasma cells - abundant - important.

Image:

Retinal hemorrhage

See Traumatic brain injury in infants.

Image:

Glaucoma

General

  • Leading cause of irreversible blindness.

Classification:

  • Open angle - more common.
  • Closed angle.

Microscopic

Features (closed angle):

  • Cornea and iris opposed to one another.

Malignant entities

Retinoblastoma

General

  • Rare.
  • Malignant.
  • May be familial.[14]

Microscopic

Features:

Image:

Notes:

  • DDx of Flexner-Wintersteiner rosette includes: pineoblastomas, medulloepitheliomas.

Malignant melanoma

Main article: Malignant melanoma

Common malignancy in the eye in adults.

Retinal detachment

General

  • Blindness.

Causes:

  • Trauma (classic).
  • Tumours - common in pathology specimens.

Microscopic

Features:

  • Retina separated from retinal pigment epithelium.
  • Eosinophilic exudate containing macrophages.

See also

References

  1. ↑ Bilbao. 24 November 2010.
  2. ↑ URL: http://www.lab.anhb.uwa.edu.au/mb140/corepages/eye/eye.htm. Accessed on: 20 October 2011.
  3. ↑ URL: http://www.ophthobook.com/questions/question-name-the-layers-of-the-cornea-and-their-function. Accessed on: 26 January 2012.
  4. ↑ Raizada, IN.; Bhatnagar, NK. (Jul 1976). "Pinguecula and pterygium (a histopathological study).". Indian J Ophthalmol 24 (2): 16-8. PMID 1031388.
  5. ↑ 5.0 5.1 5.2 5.3 Hill, JC.; Maske, R. (1989). "Pathogenesis of pterygium.". Eye (Lond) 3 ( Pt 2): 218-26. doi:10.1038/eye.1989.31. PMID 2695353.
  6. ↑ URL: http://dictionary.reference.com/browse/pterygium. Accessed on: 20 October 2011
  7. ↑ URL: http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0002006/. Accessed on: 20 October 2011.
  8. ↑ 8.0 8.1 URL: http://www.uic.edu/depts/mcpt/eyepath/specco4.htm. Accessed on: 25 October 2011.
  9. ↑ 9.0 9.1 9.2 Adams, SP. (Feb 1999). "Dermacase. Eccrine hydrocystoma.". Can Fam Physician 45: 297, 306. PMC 2328272. PMID 10065300. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2328272/.
  10. ↑ D'hermies, F.; Fayet, B.; Meyer, A.; Morel, X.; Halhal, M.; Elmaleh, C.; Azan, F.; Behar-Cohen, F. et al. (Feb 2004). "[Chalazion mimicking an eyelid tumor].". J Fr Ophtalmol 27 (2): 202-5. PMID 15029054.
  11. ↑ URL: http://emedicine.medscape.com/article/1212709-workup. Accessed on: 9 February 2012.
  12. ↑ URL: http://www.surgical-pathology.com/chalazion.htm. Accessed on: 24 January 2012.
  13. ↑ URL: http://library.med.utah.edu/WebPath/EXAM/IMGQUIZ/fofrm.html. Accessed on: 6 December 2010.
  14. ↑ Lohmann D (2010). "Retinoblastoma". Adv. Exp. Med. Biol. 685: 220–7. PMID 20687510.
  15. ↑ 15.0 15.1 Wippold FJ, Perry A (March 2006). "Neuropathology for the neuroradiologist: rosettes and pseudorosettes". AJNR Am J Neuroradiol 27 (3): 488–92. PMID 16551982.
  16. ↑ WH. 14 March 2011.
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