The document discusses the anatomy and functions of eyelid muscles, including retractors and protractors, detailing their role in maintaining the palpebral fissure and eyelid positioning. It also covers conditions such as ptosis, ectropion, and entropion, linking them to the functionality of eyelid structures. Various anatomical features, including tarsus and canthal ligaments, are described in relation to eyelid stability and lid-globe apposition.

1. THE EYELID MUSCLESHow the lids are kept in placeDr. Anupama Karanthwww.ophthalclass.blogspot.com

2. The palpebral fissure

3. What maintains the palpebral fissure?The eyelid retractorsThe eyelid protractors

4. Eyelid protractors

5. Eyelid rectractors

6. Upper eyelid retractors

7. LevatoraponeurosisWide insertion into various layers of the lidMedial horn – posterior lacrimal crestLateral horn – lateral orbital tubercleAnterior portion – skinPosterior portion – anterior tarsusSuperior tarsal muscle – conjunctiva and tarsus

8. Muller’s muscle(superior tarsal muscle)Posterior part of levator2 mm lift to the upper lidInsertion to tarsus and conjunctivaSympathetic supplyHorner’s syndrome – mild ptosis

9. Loss of retractor functionBlepharoptosis – drooping of upper eyelid

10. Lower eyelid retractors

11. Lower eyelid retractorsCapsulopalpebral fascia analogous to levatoraponeurosisFrom inferior rectus terminal fibresEncircles inferior oblique Inserts to inferior conjunctival fornix and inferior tarsal borderInferior tarsal muscle Poorly developedPosterior to capsulopalpebralfascia

12. The lid globe apposition

13. The lid and the globeWhy do the eyelids not fall outwards?Why do the eyelids not turn inwards?

14. The eyelid in placeHorizontal TARSUS - CANTHAL LIGAMENTS - BONEVertical ORBITAL SEPTUM - RETRACTORS - TARSUSThe lid globe apposition-horizontalTARSUS - CANTHAL LIGAMENTS - BONE Superior and inferior tarsus Medial and lateral canthal ligamentsLacrimalcrests and lateral orbital tubercle

15. The lid globe apposition-verticalORBITAL SEPTUM - RETRACTORS - TARSUSOrbital septumLevatoraponeurosisMuller’s muscleTarsus

16. Loss of lid-globe apposition

17. Abnormal lid-globe relationsEctropionEversion of eyelid marginEntropionRolling inwards of eyelid margin

18. Ectropion - Entropion

19. Horizontal lid laxityEctropionEntropion

20. Age related lid laxity

21. Involutionalentropion

22. Managing laxity