1. ANATOMY OF EYELID PRESENTED BY: Dr. Rahul Gupta 1 ST Year Resident Dept. Ophthalmology

2. CONTENT INTRODUCTION EMBRYOLOGY GROSS ANATOMY LAYERS OF EYELID GLANDS OF EYELID NERVE, VASCULAR SUPPLY AND LYMPHATIC DRAINAGE CLINICAL CORRELATION PHYSIOLOGY OF EYELID MOVEMENTS

3. Introduction o Mobile, flexible, multilamellar structures that cover the globe anteriorly o Helps to keep the corneas moist, and protect against injury and excessive light, o Regulate the amount of light reaching the retina. o The lids are essential for distribution and drainage of the tears

4. Embryology Derived from surface ectoderm The upper eyelids are formed from the frontonasal process The lower eyelids are formed from the maxillary process

5. Structure developedTime of gestation Appearance of the eyelid fold marks the beginning 6 or 7 week of gestation Eyelid fusion8 to 10 weeks gestation. Development of eyelid structures3 to 4 months gestation. Eyelid dysjunction5 to 6 months gestation

7. Clinical Correlation Congenital eyelid disorders: a) Cryptophthalmos: Failure of development of eyelid structures Skin continues from forehead to cheek and inner side is adherent to cornea b) Coloboma of eyelid: Usually occurs in upper eyelid c) Ankyloblepheron: Fusion of part or all of eyelid margin. In ankyloblepheron filiforme adnatum eyelids are connected via fine strands

8. d) Congenital Ectropion: Outward deviation of margin …common in lower lid…mainly due to vertical deficiency of skin e) Congenital Entropion: Inward turing of eyelid…unlike epiblepheron doesn’t resolve itself f) Epiblepheron: Horizontal fold of skin adjacent to either upper or lower lid margin (common)…can turn lashes inward against cornea Cornea during early life can tolerate this condition Usually resolves spontaneously

9. g) Epicanthus : Crescent shaped fold of skin running vertically between eyelids and overlying inner canthus  Epicanthus tarsalis: fold most prominent in Upper lid  Epicanthus inversus: fold prominent in lower lid  Epicanthus palpebralis: fold equally distributed in UL and LL  Epicanthus supraciliaris: fold arises from eyebrow and terminates over lacrimal sac h) Blepherophimosis syndrome: Blepherophimosis + Epicanthus inversus + Telecanthus + Ptosis Palpebral fissure is shortened horizontally and vertically(Blepherophimosis) with poor levator function and no eyelid fold

10. GROSS ANATOMY 1. EXTENT AND POSITION OF EYELIDS upper eyelid: extends over the orbital margin to the eyebrow above Lower eyelid: more smoothly into the cheek, where nasojugal and malar sulci may limit it At nasojugal sulcus a band of connective tissue passes between orbicularis oculi and levator labii superioris

11. The upper lid Most mobile In forward gaze the upper lid just overlaps the cornea (1/6 th ) upper eyelid margin at 1.5 – 2 mm below the superior corneal limbus The lower lid Just touches the cornea in forward gaze lower eyelid margin at inferior corneal limbus

12. 2. PARTS  Orbital part  Tarsal part 3. CANTHUS Medial canthusLateral canthus a)more obtuse b)Inferior lower rim: horizontal & a superior rim: sloping infero-medially c)Medial canthus is separated from globe by the tear lake In this area there is caruncle and plica semilunaris a)acute, about 30-40 deg with the lids wide open. b)5-7 mm medial to the orbital margin and 1 cm from the frontozygomatic suture c) lateral canthus is in contact with the globe. d)With the lids open, the lateral canthus is about 2 mm above the medial canthus

13. CARUNCLE- Modified skin containing sebaceous glands and hairs PLICA SEMILUNARIS- Highly vascular crescent shaped fold of conjunctiva.Vestigial structure analogous to nictitating membrane of animals

14. EYELID MARGINS  2mm in width  Each lid margin divided into 2 parts by lacrimal papilla  Lacrimal portion medially : devoid of lashes/glands and  Ciliary portion laterally:  rounded anterior, sharp posterior border and intermarginal strip  grey line(referred to as the muscle of Riolan and represents the pretarsal orbicularis muscle): junction of skin and conjunctiva divides intermarginal strip into ant.strip  bearing lashes and post  meibomian glands

16.  Lacrimal portion medially:  lacrimal punctum (upper & lower) exits at the summit of each lacrimal papilla  punctum divides the lid margin into medial lacrimal portion and the lateral ciliary portion.  upper punctum is more medial than lower punctum;

17. EYELASHES Approximately 100 to 150 cilia -upper eyelid, and 50 to 75 cilia - lower eyelid., arranged in two to three rows Glands of Zeis and Moll open into each hair follicle Dense plexus of nerves and vesssels around follicle – exquisite tactile sensibility

18. 6.PALPEBRAL APERTURE OR FISSURE DiameterAt birthAdult Horizontal18-21mm28-30mm Vertical8mm9-11mm

19. Trichiasis - Eyelashes are misdirected and grow inwards towards the eye Distichiasis - Abnormal growth of lashes from the orifices of the meibomian glands Clinical Correlation

20. Madarosis - Partial or complete loss of eye lashes, may be congenital or due to infection. Poliosis - Whitening of eye lashes Trichomegaly - Increase in length, curling, pigmentation or thickness of eyelashes.

21. Layers Of The Eyelids 1. Skin & subcutaneous areolar tissue 2. Muscles of protraction 3. Orbital septum 4. Orbital fat 5.Muscles of retraction 6. Tarsus 7. Conjunctiva

22. Skin o Thinner than any other part of the body o Thinnest skin in the medial upper eyelid almost transparent o Contains the usual adnexal structures: fine hairs, sebaceous & sweat glands

23. o Nasal skin is shinier, smoother and greasier, devoid of hair. well provided with unicellular sebaceous glands, hence xanthelesma develops on the nasal side. o Sweat glands - small numerous, more on the lateral aspect of the eye lid.

24. Layers of the skin Epidermis: It consist of 4 layers of keratin producing cells; o stratum corneum o stratum granulosum o Stratum spinosum o stratum basale Dermis : Thin layer of dense connective tissue with rich network elastic Fibres, blood vessels, lymphatics and nerves.

25. Subcutaneous Areolar Tissue: o loose connective tissue arrangement o elastic in nature. o no fat o Applied Anatomy - fluid from oedema or haemorrhage rapidly engorges the loose subcutaneous eyelid tissue & produce dramatic eyelid swelling and recovers rapidly as well.

26. The Orbicularis Oculi Muscle o complex striated muscle sheet o divided anatomically into three contiguous parts – o Orbital o Palpebral - Preseptal Pretarsal

27. Orbital Part: Orbital orbicularis portion extends superiorly to the eyebrow, where it interdigitates with the frontalis and the corrugator superciliaris muscles. Medially, it extends from the supraorbital notch in a curvilinear fashion over the side of the nose, inferiorly to the infraorbital foramen. It continues along the infraorbital margin. Laterally, it extends to the temporalis muscle. These thick course fibers play an important role in voluntary lid closure (winking) and forced eyelid closure.

28. Pretarsal part Superficial origin -Medial canthal tendon Deep origin – posterior lacrimal crest Deep heads fuse near common canaliculus to form Horners muscle (Pars lacrimalis) Contraction of which draws the eyelids medially and posteriorly. The resulting lateral pull creates a negative pressure in the lacrimal sac and draws the tears from the canaliculi into the sac. Laterally attaches at lateral canthal tendon

29. Preseptal part: The medial origin : from two heads  the deep: lacrimal sac and lacrimal fascia  the superficial heads: anterior rim of the medial canthal ligament  Laterally, inserts directly onto Whitnall's lateral orbital tubercle 3 to 4 mm deep to the lateral palpebral raphe.

30. Closes the eyelids Contraction of these fibers aid in the lacrimal pump mechanism. Function of eyelid

31. Muscle Of Riolan o Small bundle of striated muscle fibers at the eyelid margin o Extension of orbicularis oculi fibers and contributes to keeping the lids in close apposition.

32. Horner’s Muscle o Prominent bundle of fibers, formed by fusion of the deep heads of the pretarsal orbicularis o Runs just behind the posterior limb of the canthal tendon o Insertion - Posterior lacrimal crest o Functions - Helps to maintain the posterior position of the canthal angle Tightens the eyelids against the globe during eyelid closure Aid in the lacrimal pump mechanism

33. Orbital Septum  Thin, fibrous, multi layered membrane

34. Upper Lid o Arcus marginalis(Condensation of periosteum of forehead with the periorbita of orbit at the supraorbital rim) o Fat within the fibroadipose layer Anterior to the orbital septum Mistaken for the preaponeurotic fat pad during eyelid surgery

35. Lower eyelid Attaches with Inferior orbital rim Condensation of periosteum & periorbita Continues anteriorly and superiorly o 4-5 mm below inferior tarsus Joins with lower eyelid retractors Inserts on lower border of inferior tarsus

36. o Applied Anatomy: Eyelid is a barrier to orbital fat / extravasation of blood / spread of infection With age, orbital septum weakens  orbital fat herniates  Dermatochalasis

37. The Preaponeurotic Fat o anterior extensions of extraconal orbital fat o in the upper eyelid - medial & central fat pockets o in the lower eyelid - medial, central & lateral fat pockets

38. Applied Anatomy – o surgically important landmarks (immediately anterior to the major eyelid retractors) o Excessive traction during Lower lid surgery transmitted deeper into the orbit Intraoperative or postoperative orbital hemorrhage

39. The Eyelid Retractors:

40. LEVATOR PALPEBRAE SUPERIORIS originates from the lesser wing of the sphenoid bone, superolateral to the optic foramen As the triangular levator muscle courses anteriorly in the orbit from its origin, it is composed of striated muscle. The average length of the muscular portion of the levator is 36 mm. At the level of the globe, fans out and thins as the whitish gray superior transverse ligament of Whitnall or Whitnall's ligament. forming the more vertical levator aponeurosis(18 mm width)..

41. The medial horn of the levator attaches to the medial canthal ligament. Its attachment is looser and more ill- defined The lateral horn of the levators splits the lacrimal gland into the larger orbital lobe and the smaller palpebral lobe Attaches to the lateral orbital tubercle by the lateral canthal tendon

43. Supratarsal Muscle Of Muller  - The sympathetic accessory retractor of upper eyelid  modulates the position of the upper and lower eyelids when the eye is open.  Origin - undersurface of the levator muscle, just anterior to Whitnall’s ligament  Insertion - anterior edge of the superior tarsal border

44. Capsulopalpebral Fascia - fibrous extension arises from the inferior rectus muscle - Capsulopalpebral head splits to surround the inferior oblique muscle. - Capsulopalpebral fascia - Inferior tarsal muscle  The two layers fuse anterior to the inferior oblique muscle to form a dense fibrous structure termed Lockwood's suspensory ligament of the globe  The outer fibers of the capsulopalpebral fascia fuse with the inner fibers of the inferior orbital septum 4 to 5 mm below the inferior tarsus and together advance as a single layer to insert on the inferior border of the inferior tarsus

46. The Eyelid Retractors - The upper eyelid has a maximal excursion of about 15 mm without participation of the frontalis muscle. - The lower eyelid has maximum excursion of about 5 mm from up gaze to down - The width of the palpebral fissure is determined by the level of tonic activity in the levator palpebrae superioris and the sympathetically innervated Müller’s muscle.

47. Tarsal plate 29-30mm long,1 mm thick Height o 10-12 mm Upper lid o 4-5 mm Lower lid Thickened fibrous connective tissue Structural support to eyelids Medially and laterally o Connected to orbital margins by ligamentous fibrous tissue Tarsal ( Meibomian gland ) within the tarsal plate

48. The Conjunctiva - Transparent vascularized membrane covered by a non-keratinized epithelium that lines the posterior surface of the eyelids (palpebral conjunctiva)and the anterior surface of the globe (bulbar conjunctiva). - Firmly adherent to the tarsus, for free mobility. - Small accessory lacrimal glands (Glands of Krause & Wolfring) are located within the submucous connective tissue

49. Glands Meibomian glands Glands of Zeis Glands of Moll Glands of Wolfring Glands of Krause

50. Glands of the Eye & Adnexa GlandsLocationSecretionContent LacrimalOrbitalExocrineAqueous Sweat GlandPalpebralExocrineAqueous Accessory LacrimalPlica, CaruncleExocrineAqueous KrauseEyelidExocrineAqueous WolfringEyelidExocrineAqueous MeibomianTarsusHolocrineOily ZeisFollicle of cilia Eyelid, Caruncle HolocrineOily MollEyelidEccrineSweat Goblet CellConjuctiva Caruncle, Plica HolocrineMucus

51. Meibomian Glands o Multilobulated holocrine- secreting sebaceous glands within each tarsus o Oriented vertically o with central ductule that opens onto the eyelid margin posterior to the gray line. o 30-40 no. in upper eyelid & 20- 30 no. in lower eyelid

52. o It produces sebum - oily material that forms the lipid layer of the precorneal tear film o Functions: Retards evaporation of the aqueous component of the tear fluid Hydrophobic barrier at the margin of the eyelid, preventing spillage of tears at the lid margin.

53. Nerve Supply To The Eyelid Motor Nerve Supply: Motor nerves to the orbicularis oculi muscle - facial nerve (temporal & zygomatic branches) Motor nerve to the levator palpebrae superioris -Superior division of oculomotor nerve Motor nerve to the Müller muscle - sympathetic nervous system

54. Nerve Supply To The Eyelids Sensory Nerve Supply : Ophthalmic & maxillary divisions of the trigeminal nerve Upper eyelid - supraorbital, supratrochlear & lacrimal nerves (ophthalmic division) lateral portion of upper eyelid – zygomatico- temporal branch of the maxillary nerve extreme medial portion of both upper & lower eyelid - infratrochlear nerve

55.  Sensory Nerve Supply continued:  lower eyelid - infraorbital nerve (maxillary division)

56.  Marginal Arcade  Submuscular plane  In front of tarsal plate  3-4 mm from lid margin  Lacrimal Artery Lateral Palpebral Artery  Dorsal Nasal Artery Medial Palpebral Artery  Peripheral Arcade  Superior branch of Medial Palpebral Artery  Upper border of Tarsus Arterial Supply

57. Venous Supply To The Eyelids Venous Drainage Divided into pretarsal and postarsal  - Pretarsal which opens into subcutaneous veins and futher drains into angular vein medially and superficial temporal vein laterally.  - Postarsal drainage is into orbital veins, then to ophthalmic vein and to cavernous sinus.

58. Lymphatic Drainage restricted to the region anterior to the orbital septum o lateral most of the upper eyelid drains into pre-auricular node and small part of the middle of the upper eyelid and the inner half of the lower eyelid drains into the submandibular lymph nodes. o Preauricular and deep parotid nodes eventually empty into the deep cervical nodes near the internal jugular vein. o submandibular nodes eventually empties into the internal jugular vein.

59.  External Hordeolum (Common Stye)  Localized suppurative inflammation of gland of Zeis and glands of Moll’s at lid margin at ciliary follicle. Clinical Aspects

60.  Internal Hordeolum( Meibomian stye)  Internal Hordeolum is a suppurative inflammation of meibomian gland associated with the blockage of the duct.

61.  Chalazion  Chronic granulomatous inflammation of meibomian gland or sometimes Zeis glands caused by retained sebaceous secretions  Ocurrs secondary to obstruction of the gland duct.  More common in upper eyelid appearing as hard, immobile, painless, roundish lump.

62.  Blepharitis  Blepharitis is subacute or chronic inflammation of lid margin occurring as true inflammation.  Bilateral and often misdiagnosed as conjunctivitis  Types:  Anterior Blepharitis  Affects the base of eyelashes and may be Staphylococcal, Seborrhoeic or parasitic.  Staphylococcal:  In case of Staphylococcal – Red eyes and peripheral corneal infiltrates (more common in atopic dermatitis)  Common cause of ocular discomfort and irritation

63.  Yellow crusts are seen at the root of cilia  Small ulcers which bleed easily on removal of clusters

64.  Seborrheic Blepharitis  Primary anterior blepharitis with some posterior spill over  Usually associated with seborrhea of scalp(dandruff)  Accumulation of white dandruff like scales on lid margin

65.  Parasitic Blepharitis  Due to crab louse very rarely to head louse  Presence of nits at the lid margin and at roots of eyelashes  Conjunctival congestion may be seen on long standing

66.  Meibomitis ( Posterior Blepharitis)  Inflammation and obstruction of meibomian glands. Characterized by diffuse thickening of posterior border of lid margin which becomes rounded.

67.  Involutional entropion: Age related inward rolling of eyelashes mainly affecting lower lid Constant rubbing on the cornea cause irritation, corneal punctate epithelial erosions and sometimes ulceration Entropion

68.  Cicatricial entropion Scarring of the palpebral conjunctiva can rotate the upper or lower lid margin towards the globe Causes include cicatricial conjunctivitis, trachoma, trauma and chemical injuries

69.  Involutional ectropion Age related outward rolling of eyelid margin mainly affecting lower lid Causes epiphora and on long standing become chronically inflamed and keratinized Ectropion

70.  Cicatricial ectropion Caused by scarring or contracture of the skin and underlying tissues which pulls the eyelids away from the globe.  Paralytic ectropion Caused by ipsilateral facial nerve palsy Associated with retraction of upper and lower lids an brow ptosis  Mechanical ectropion Caused by tumors on or near lid margin that mechanically evert the lid

71.  Incomplete closure of the palpabral aperture when attempt is made to close the eyes voluntarily.  Occurs due to paralysis of orbicularis oculi muscle, cicatricial contraction, symblepharon, severe ectropion, proptosis etc. Lagopthalmos

72.  It is the involuntary, sustained and forceful closure of the eyelids. Occurs in 2 forms: 1.Essential (Spontaneous) blepharospasm 2.Reflex blepharospasm. Blepharospasm

73.  It is a partial or complete adhesion of the palpebral conjunctiva of the eyelid to the bulbar conjunctiva of the eyeball. Symblepharon

74. Ptosis Abnormal Drooping of the upper eyelid is called ptosis. Normally, upper lid covers about upper one-sixth of the cornea, that is 2mm. So ptosis cover more than 2mm. TYPES: 1. Congenital Ptosis; - It is associated with congenital weakness (maldevelopment) of Levator palpebral Superioris muscle. 2. Acquired Ptosis; - Depending upon cause it can further be: a. Neurogenic Ptosis b. Acquired myogenic Ptosis

75. c. Aponeurotic Ptosis d. Mechanical Ptosis

76. PHYSIOLOGY OF EYELIDS MOVEMENT Basically Opening and closing movements, however depending on mechanics and neural control: a)Blinking b)Winking c)Peering d)Forceful closure

77. OPENING MOVEMENTS; Muscles concerned: a)Upper lid i.LPS( primary elevator) ii.Frontalis (accessory elevator) iii.Superior palpebral muscle of Muller b)Lower lid No true counterpart of LPS present. Opening depends on: i.Elastic recoil of lower lid tissues ii.Traction exerted by attachment of IR to inferior tarsus and inferior palpebral muscle of Muller

78. Opening movements are b/l symmetrical in direction and amplitude. However it can be voluntarily inhibited on one side  Levator muscle of both eyes act as Yoke muscles (Thus follow Herings law of equal innervation)  In U/L congenital ptosis, lid on unaffected side may be retracted (based on Hering's law), to elevate the ptotic lid.  Levator and Orbicularis however follow Sherrington's law of reciprocal innervation.  When levator receives maximum innervation during eye opening orbicularis receives minimum innervation and vice versa.

79. Dynamics As upper eyelid begins to move upward from closed position a tremor(0.2 to 0.3mm in amplitude )is present Upper lid moves vertically upward while lower lid moves laterally in horizontal direction Overshoots of opening followed by small recovery is frequently seen

80. CLOSING MOVEMENTS Muscle concerned: Orbicularis oculi….7 th CN Although it is a single muscle, physiologically its 3 regions act as 3 independent muscles. 3 functional units of orbicularis are: a)Pretarsal fibers: respond in spontaneous blinking and tactile corneal reflex b)Preseptal fibers: respond in voluntary blinking and sustained activity c)Those responding in forceful closure of lids which include all 3 regions: pretarsal, preseptal and orbital fibers

81. During closing movements: Upper lid moves down vertically while lower lid moves medially (horizontal) Movement of lower lid begins 10-20 msec before upper lid Gravity does not play a role in downward movement of upper lid(speed same irrespective of head position)

82. PEERING Act of looking at something with great interest Upper lid moves down by 2.5 mm and medially by 1 mm Movement of lower lid begins 200msec before that of upper lid (similar as in closing movement) Downward movement of upper lid in peering …mechanism unclear Its found that relaxation phase of peering is initiated by decrease in tone of orbicularis …and the lids then come in normal position

83. BLINKING Coordinated opening and closing movements of eyelids Complete blink: begins in alert open position reaches halfway point when upper and lower lids appose each other along atleast one half of their ciliary margins. Ends when upper and lower lids return to starting alert position Blinking: i.Voluntary ii.Involuntary(spontaneous & reflex)

84. SPONTANEOUS BLINKING Without external stimulus Does not occur or infrequent during early months of life(corneal dryness doesn’t occur) Also present in blind people (retinal stimulation is not required) Functions Redistribution of tear film Protection Rest for EOM(blinking allows momentary upturning of eyes=analogous to position of eyes during sleep)

85. Blink rate=12-20 / min Duration of blink < 300 msec Spontaneous blink doesn't produce discontinuation of vision despite vision is interrupted for a fraction of second

86. REFLEX BLINKING 1) Tactile reflex blinking: Sudden unexpected touch to cornea, conjunctiva, eyelash, eye brow or lids Blink response arising from corneal touch is nociceptive, polysynaptic brainstem reflex B/L response although only 1 cornea is touched Begins 5 msec before on the ipsilateral side than contralateral side Afferent pathway: 5 th CN Efferent pathway: 7 th CN

87. 2) OPTIC REFLEX BLINKING a) Dazzle reflex: Produced by shining bright light into eye Subcortical so it may be lost in mesencephalic lesion b) Menace reflex: Unexpected object coming to near field of vision Cortical (cortical lesions: menace reflex lost….corneal tactile and Dazzle +nt)

88. 3) AUDITORY REFLEX BLINKING Afferent: 8 th CN Efferent:7 th CN 4) Stretch type stimulus reflex blinking: When orbicularis is stimulated by stretch type stimulus(tap or blow) Electrical activity in orbicularis in this type of reflex of 2 types: a)Fast proprioceptive component…arises from stimulation of stretch receptors in orbicularis..this is a segmental reaction …doesn’t require interneuron between afferent and efferent fibers b)Nociceptive component: has polysynaptic pathway like tactile reflex

89. Neural control of eyelid movements Opening movements: 1)Volunatry eyelid opening movements: Controlled by frontal eyefield area in frontal cortex Stimulation of this area results b/l eyebrow elevation and eye opening 2) Involuntary eyelid opening movements: Controlled by occipital motor area which sends signals to frontal eye field area 3)Fine control of levator tone: Extrapyramidal function

90. Closing movements: 1)Voluntary closing movements: controlled by area 4 (facial region of precentral motor cortex) 2)Spontaneous and reflex blinking: Arise in subcortical centre and regarded as extrapyramidal movements END

91. References OPHTHALMOLOGY ANATOMY AND PHYSIOLOGY OF EYE KHURANA ; Author Khurana A. K Edition: 3 rd AMERICAN ACADEMY OF OPHTHALMOLOGY online resources KANSKI’S CLINICAL OPHTHALMOLOGY; A SYSTEMIC APPROACH- NINTH EDITION