The document provides an extensive overview of embryology, anatomy, and physiology regarding the eyelids, detailing their formation, structure, muscles, and functions. It covers topics such as the development of eyelid folds, the arrangement of various layers, and the mechanisms of eyelid movement including opening and closure facilitated by different muscles. Additionally, it discusses the vascular and nerve supply, along with the roles of various glands associated with the eyelid.

1. By Dr.Vaibhav k
Moderator : Dr.Anupama.T

2. Introduction

3. Embryology
 Formed by reduplication of surface ectoderm
above and below the cornea during second
month of gestation.
 The folds enlarge and their margins meet and
fuse with each other
 The lids cut off a space called conjunctival
sac.
 The folds thus formed contain some
mesoderm for development of muscles of lid
and tarsal plates.
 Lids seperate after 7th
month of intrauterine
life

5. 1) Extent
2) Lid folds
3) Position of eyelids
4) Canthi
5) Eyelid Margins
6) Eyelashes
7) Palpebral aperture or fissure
Gross Anatomy

6. Extent
 Upper eyelid
 From eyebrow downward to end in a free margin
 Superior boundary of palpebral fissure
 Lower eyelid
 Merge into skin of cheek, where nasojugal,malar sulci
limit it.

7. Lid folds
 Superior lid fold
 Orbital & tarsal portion
 Formed by fibrous slips, from tendon of
levator
 Inferior lid fold
 On skin of lower eyelids
 Fibrous slips from fascia of inferior rectus

8. Position of eyelids
 In primary position of gaze
Upper eyelid covers 1/6th
of cornea
Lower eyelid just touches the cornea

9. Canthi

10.  the two eyelids are separated by lacus
lacrimalis, in the centre of which is a small
pinkish elevation;
 the caruncula lacrimalis.it is a small area of
tissue derieved from skin,contains large
modified sweat glands and sebaceous glands.
 A semilunar fold called plica semilunaris lies on
lateral side of caruncle.Represnts the third eye
lid of other vertebrae.

11. Eyelid Margins

12.  Lid margin vascularity increases with
age,particularly in women.

13. Eyelashes
 2-3 rows
 When lids close eyelashes do not interlace
 Upper lid : 100-150
 Lower lid : 50-75
 Cilia
 20 – 120 microns
 Taper & end in fine point
 Lifespan 5 months.
 Replacement is fully grown in 10 wks.
 Darker than other hairs and remain so except in alopecia areata.
 Glands of Zeis & Moll- empty into infundibulum of each piliary gland

14. Ciliary follicles:
 Cilia have no erector muscles set
obliquely,anterior to palpebral muscle reach
the tarsal plate, have a sensory innervation.

15. Palpebral aperture
 Elliptical space b/w upper & lower lid
margins
 At Birth
 Horizontally– 18 to 21 mm
 Vertically -- 8mm
 In Adults
 28 to 3o mm (hor)
 9 to 11 mm (ver)

16. Structure
 From without inwards, each lid has following layers:
1) Skin
2) Layer of subcutaneous areolar tissue
3) Layer of striated muscles(orbicularis
oculi)
4) Sub muscular areolar tissue
5) Fibrous layer and tarsal plate.
6) Septum orbitale
7) Layer of non-striated muscle fibres
8) Conjunctiva

18. Skin
 Elastic , fine texture, thinnest in the
body(<1mm)
 Almost transparent.
 The skin of medial part of eye lid differs from
temporal .more oily,few rudimentary
hairs,sebaceous glands,plentiful unicellular
sebaceous glands in basal epidermis.

19. Epidermis
6-7 layers , stratified squamous epithelium
Basal layer- unicellular sebaceous glands, sweat glands
Dermis
Thin layer , dense connective tissue
Rich network : BV, elastic fibers, lymphatics, nerve
Variable no. of melanocytes

20.  The mucocutaneous junction is just behind
openings of tarsal glands,i.e. junction of
wettable and non wettable surfaces,
representing ant limit of of marginal strip of
tear fluid.

21. Subcutaneous areolar tissue
 Beneath the skin
 No fat
 Readily distended by blood/ oedema
 Nonexistent
 Near ciliary margin
 At lid folds
 Medial & lateral angles

22. Layer of striated
muscle
 Orbicularis muscle , thin oval sheet
across eyelids
 Upper eyelid- also has levator muscle

23. Orbicularis oculi muscle

24. Orbital part
 From anterior part of the medial palpebral
ligament & adjacent bones
 Cover orbital margins , large ellipse , meet at
lateral palpebral raphe
 Intermingle with frontalis

25. Palpebral part of
orbicularis
 Preseptal fibres
 Pretarsal fibres

26. Preseptal fibres
 Deep head & superficial head
 From lacrimal fascia, posterior lacrimal
crest, MPL
 Pass superiorly & inf. In front of orbital
septum
 Unite at lateral palpebral raphe

27. Pretarsal fibres
 Deep head
 From lacrimal fascia & post. Lacrimal crest
 Superficial head
 From medial palpebral ligament
 Overlying upper & lower tarsus
 Join laterally to form lateral canthal tendon
 It is inserted over lateral orbital tubercle of
WHITNALL
 Pars lacrimalis (Horner’s muscle)
 Pars ciliaris (muscle of Riolan)

28. Function of orbicularis
oculi
 Orbital part
 Forced closure of eyelids
 Thus pull eyebrows downwards
 Palpebral part
 Helps in gentle closure during blinking, sleep, soft
voluntary closure
 Entire muscle supplied by branches of 7th
nerve

29. Levator palpebrae
superioris
 Origin
 Course &
attachments
 Superior
transverse
ligament of
Whitnall
 Nerve supply &
action

31. Origin of LPS
 At apex of orbit from the Under surface of
lesser wing of sphenoid above Annulus of
Zinn by a Short tendon whuch is Blended
with origin of SR

32. Course & attachments
 Ribbon like belly
 Axis slightly nasal
 Medial & lateral horns
 Aponeurosis passes through septum orbitale
 LPS inserted – pretarsal skin of lid forming the
sup.lid fold
 Thickened posterior part- ant tarsal surface
 Few fibrous slips from post.LPS insert into
sup.conj. Fornix

33. Sup. Transverse lig. Of
Whitnall
 Thickened band of orbital fascia
extending From trochlear pulley to the
capsule of orbital lobe of lacrimal
gland.
 Formed by condensation of superior
sheath of levator muscle joined
medially by the sheath of reflected
tendon of superior oblique muscle

34.  Severing of this ligament during ptosis
surgery can lead to failure of levator function.

35. Nerve supply & action of
LPS Branch of superior division of 3rd
nerve
 Acts as Elevator of upper lid.

36. Submuscular areolar
tissue Layer of loose connective tissue
 b/w orbicularis muscle & fibrous layer
 Nerves & vessels lie in this layer
 Splits lid into anterior & posterior lamina
 Superiorly communicates with
subaponeurotic layer of scalp

37.  Lower lid – submuscular tissue is a single space
behind orbicularis
 Upper lid- levator muscle- divides into 2 spaces
› Pretarsal space- has peripheral arcade
› Bounded anteriorly by levator
tendon,orbicularis,posteriorly by tarsal plate,palpebral
muscle.
› Limited by origin of this muscle from levator,below by
attachment of levator to tarsal plate.
› Preseptal space- triangular, bounded in front by
Orbicularis, behind by septum orbitale

39. Fibrous layer
 Framework of the lids
 Central thick part- tarsal plate
 Peripheral thin part- septum orbitale/
palpebral fascia

41. Tarsal plates
 Dense fibrous tissue, skeleton of lids
 Extend from a point 7mm from lateral orbital
tubercle to lacrimal puncta,9mm from anterior
lacrimal crest.
 29mm long, 1mm thick
 Superior tarsus is transversely cresentric
 Inferior tarsus is oblong.
 Surfaces: anterior and posterior
 Tarsal glands embedded in substance of tarsal
plates

42. Capsulopalpebral fascia:
 i. Origin: as capsulopalpebral head from
delicate attachments to inferior rectus
muscle
 ii. Extends anteriorly and splits into two and
surrounds the inferior oblique muscle
 iii. Again rejoins to form the Lockwood’s
ligament and fascial tissue anterior to this
forms the capsule palpebral fascia
 iv. Insertion: on the inferior fornix along
with inferior tarsal muscle and on inferior
border of tarsus

44. Septum
orbitale(palpebral fascia) Thin , floating membrane of
connective tissue
 Takes part in all movements of lids
 Thick & strong on lateral side,in
upper lid than lower lid.

45.  Peripherally attached to orbital margins
called arcus marginale formed by periorbita
when it continues with periosteum of facial
bones.
 Centrally it becomes continuous with tarsal
plates except where pierced by fibres of
levator in upper lid.
 Weak areas in septum orbitale determines
the site of herniation of fat(orbital)

46. Relations
 Upper lid:
• In contact with orbital fat which seperates it
from larimal gland ,levator,tendon of sup
oblique muscle.
• Medially contact with orbital fat between
trochlea,medial palpebral ligament.
 Lower lid:
• Contact with orbital fat,expansions of inf and
superior rectus.

48. Structures piercing orbital
septum Lacrimal vessels & nerves
 Supraorbital vessels & nerves
 Supratrochlear artery & nerve
 Infratrochlear nerve
 Anastomosing vein b/w angular & ophthalmic
 Superior & inferior palpebral arteries
 Aponeurosis of levator muscle in upperlid
 Expansion of inferior rectus in lower lid

49.  Triangular band of connective tissue
 Attached to frontal process of maxilla
 From ant. Lacrimal crest
 To suture line of frontal process with nasal
bone
 Divided into 2 parts
› Ant. part of MPL
› Post. part of MPL

51. Lateral palpebral
ligament
 Thin band
 Lateral- whitnall’s tubercle
 Medially attached to lateral ends of
upper,lower tarsal plates.
 Anterior surface- related to lat.palpebral
raphe
 Posterior surface- check ligament of LR
 Upper border- aponeurosis of levator muscle
 Lower border- IO ,IR

53. 6. Layer of non striated
muscle:
 Consists of smooth muscle fibres of muller,
which lie deep to septum orbitale.
 Origin: arise from the inferior terminal
striated fibres in upper lid,from expansion of
inf rectus in lower lid.
 Supplied by sympathetic nerve fibres.
 So sympathetic irritation leads to retraction
of lids, paralysis leads to horners syndrome.

54. 7. Conjunctiva
 It is the posterior most layer of eyelidwhich
extends from m ucocutaneous junction at lid
margin to conjunctival fornix.
 It is firmly adherent to posterior surface of
tarsal plate,mullers muscle.

55. Glands of Eyelids

57. The tarsal glands

60. Glands of Zeis
 Modified sebaceous glands
 Structure
 Microscopy
 epithelium on basement membrane
 Cuboidal cells actively dividing
 Secretion
 Sebum, prevents lashes becoming dry
 Oily layer of tear film

61. Glands of Moll
 Modified sweat gland
 Gross structure
 Unbranched spiral shape
 Fundus, body, ampullary portion & neck
 Duct passes through dermis,epidermis,terminate between 2
lashes
 Microscopic structure
 Secretory part- cylindrical cell
 b/w cells & bm – myoepithelial cells
 Ducts lined by one/two layers of cells

62. Acessory lacrimal glands of
wolfring
 Microscopic accessory lacrimal glands
present along upper border of superior tarsus,
along lower tarsus inferior border.
 2-5 in upper lid
 2-3 in lower lid

64. Arterial supply
 Mainly by medial &
lateral palpebral arteries
 Marginal Arterial arcades
 Medial palpebral + lateral
palpebral
 Superior or peripheral
arterial arcade
 Superior branches of medial
palpebral artery
 Tarsal arcades
 Superficial temporal artery
 Transverse facial artery
 Infraorbital artery

66. Venous drainage
 Pretarsal Venous Plexus
 Superficial to the tarsus
 Angular vein– Internal jugular vein ,
 sup. temporal, lacrimal vein
 External jugular vein
 Post-tarsal venous plexus
 Structures posterior to tarsal plate
 Ophthalmic veins

67. Nerve supply

68. Contd.
 Sympathetic nerves
 Supply Muller’s muscle
 Vessels & glands of skin
 Arrangement of Nerves
 Submuscular plane.so to anesthetise lid,inj is given
in this compartment
 From here branches pass Forward for orbicularis &
skin
 Backward to tarsal structures & conjunctiva

69. Lymphatics

70. EYELID MOVEMENT

71.  Lid opening
 Lid closure
 Blinking
 Voluntary blinking and winking
 Bell’s phenomenon

72. Lid opening
Upper lid elevators
Lower lid retractors

73. Upper lid elevators
 Levator palpebrae superioris (the
primary elevator of the upper eyelid).
 The superior palpebral muscle of Muller’s
 Frontalis (acting as accessory elevator).
Frontalis and Muller’s muscles become important
when the levator is defective.

74. Muscle Attachment Nerve supply
Levator palpebrae
superioris
(main upper lid
retractor)
Lesser wing of the
sphenoid to the
tarsal plate
Superior division of
the oculomotor
nerve (also supplies
the SRM).
Muller’s muscle
(minor upper lid
retractor)
Aponeurosis of the
levator to the upper
border of the tarsal
plate
Sympathetic
Frontalis Scalp to the upper
part of the
orbicularis oculi

75. Eyelid excursion during opening
movements:
 In adults the upper eyelid is raised
some 10-15 mm from extreme
downward gaze to extreme upward
gaze.

76. Tone of levator muscle:
 In upward gaze, tone increases in both
the superior rectus muscle and the
levator, resulting in elevation of the
visual axis and concomitant elevation
and retraction of the upper lid.

77. Lower lid retractors
 NO true counterpart of the levator is
present, and therefore, the opening
movement depends upon several
factors:
1. Traction exerted by the attachment of
the inferior rectus to the inferior tarsus.
2. Inferior palpebral muscle (identical to
Muller’s muscle in the upper lid).

78. Dynamics of opening movement
 Opening of the upper eyelid takes place
against gravity.
 Opening movements of the homolateral
upper and lower eyelids begin in phase,
although the opening movement of the
lower lid is much slower than that of the
upper eyelid due to lack of any direct
muscular pull.

79.  During opening movement the upper
lid moves vertically upwards, while
the lower lid moves laterally in a
horizontal direction.

80.  Bilateral coordination and their basis:
 Opening movements of the eyelids are bilateral,
symmetrical, and identical in direction and
amplitude, although they may be voluntarily
inhibited on either side.
 So, the levator muscles of the two upper eyelids
behave as yoke muscles in that they act as a
team or pair, and like extraocular muscles, obey
Hering’s law of equal innervation.

81.  This implies that the innervational
energy reaching the one levator muscle
is equal to that reaching the other.
 When the levator on one side is weak, as
in unilateral myasthenia gravis or
unilateral congenital ptosis, the lid on
the unaffected side may be retracted in
an unconscious effort (based on Hering’s
law of equal innervation) to elevate the
ptotic lid.

82. Reciprocal innervation pattern
 It exists between the levator muscle
and the orbicularis oculi muscle, i.e.
when levator receives maximum
innervation during opening the
orbicularis receives minimum
innervation and vice versa. Thus, these
muscles follow the Sherrington’s law of
reciprocal innervation.

83. Lid closure

84. Orbicularis oculi controls lid closure and is
supplied by the facial nerve.
It is divided into three main parts:

85. Part Position Function
Pretarsal fibers In front of the
tarsal plate
* Respond in spontaneous blinking
and tactile corneal reflex.
* Close lid and pull lacrimal puncta
medially.
Preseptal fibers In front of the
orbital septum
Respond to voluntary blinking and
sustained activity.
* Pull lacrimal fascia laterally and
create a relative vacuum in lacrimal
sac-improve tear drainage.
Orbital fibers Surrounds the
orbital rims
* Respond in forceful lid closure.

86. Blinking can be divided into
voluntary and involuntary
types.
The involuntary blinks are
further subdivided into
spontaneous and reflex
blinks.

87. Spontaneous blinking
 It is a common form of blinking that occurs
without any obvious external stimulus or
voluntary willed efforts.

88.  Spontaneous blinking does not occur or is very
infrequent during the first few months of life; yet
the delicate infant cornea does not suffer from
dryness.
 Average rate: 15 times per minute (12-20).
 The blink rate is increased in:
1. Extremely dry conditions.
2. Strong air currents.
3. Certain emotional stress situations (surprise, anger,
or fight).
 A decreased blink rate occurs during times of visual
observations.

89.  Duration: 0.3-0.4 second.
 Present in the blind, hence no retinal
stimulation is required.
 No discontinuity of visual sensation during
blinking.
 The upper lid begins to close with no lower lid
movement.
 It is followed by a zipper-like movement from
the lateral canthus towards the medial canthus.
 This helps the displacement of the tear film to
the lacrimal puncta which are located on the
medial side of the lids.

90. Mechanism
 The exact stimulus for spontaneous
blinking is unknown.
 Spontaneous blinks occurring
without gaze shifts are triggered by
a timing mechanism probably
located in the brainstem.

91.  During each blink, the upper eyelid
covers the center of the pupil for a
period of 0.10 sec.
 Due to contraction of the preseptal
fibers, as the upper eyelid reaches the
limit of its downward excursion,
electrical activity in the orbicularis
ceases and concomitantly activity
reappears in the levator.

92. Reflex blinking
reflexly in a response to a
stimulus.

93. Different stimuli induce a different
neurological pathway.
Blinking
reflex
Examples Afferent Efferent Central
connection
Tactile Corneal touch CNV CNVII Cortical
Dazzle
(optic)
Bright light CNII CNVII Subcortical
Menace
(optic)
Sudden presence of
near object
CNII CNVII Cortical
Auditory Loud noise CNVIII CNVII Subcortical
Orbicularis Stretching of
panorbital structure
(tap/blow)
CNV CNVII Cortical

94. Voluntary blinking and winking
is a willed coordinated closure and
opening movement of the eyelids in
both eyes.
 The voluntary blink is under the control
of the individual (rate and degree of
closure and opening).
 It is produced as a protective gesture.

95. Winking is unilateral voluntary lid closure.
 Part of facial expression.
 It is a learned activity.
 Occasionally, a subject may learn to wink with
one eye but not with the other.
 Minimum periods between winks are 0.3 sec.
 Both are voluntary blinking and winking are
produced by simultaneous contraction of
palpebral and orbital portions of the
orbicularis.

96. BELL’S PHENOMENON
 It is a highly coordinated reflex
between the facial and oculomotor
nuclei, whereby on closure of the
eyelids, the eyeball is rotated
upward and outward.
 This is a protective mechanism

97.  On closure of the eyelids, all the electrical
activities in the levator cease and concomitantly
the activity abruptly rises in the superior rectus
muscle and is inhibited in the inferior rectus
muscle.
 Bell’s phenomenon is NOT present in 10% of
otherwise healthy persons, and therefore its
absence is not necessarily a sign of disease.

98. Applied aspects
 Congenital anamolies:
 Congenital ptosis
 Coloboma: characterised by full thckness
triangular gap in tissues of lids.
 Involves nasal side.more common in upper
lid.
 Cryptophthalmos:lids fail to develop and skin
passes continuously over the eye balls.

99.  Microblepharon: abnormally small eye
lids.associated with microphthalmos or
anophthalmos.
 Ablepharon: ocasionally lids may be virtually
absent

100. Inflammatory disorders of
eye lids
 Blepharitis : subacute or chronic
inflammation of eye lids.
• Seborrhoeic blepharitis
• Ulcerative blepharitis
 Posterior blepharitis.
• Chronic meibominitis
• Acute meibominitis.

101.  External hodeolum:
• Acute suppurative inflammation of gland of
zeiss or moll.
 Chalazion : tarsal or meibomian cyst.chronic
non infective granulomatous inflammation of
meibomian gland.

102.  Internal hordeolum: suppurative inflamation
of meibomian gland asso with blockage of
duct.
 Molluscum contagiosum: viral infection of lids
caused by a pox virus.
 Waxy,umbilicated,multiple swellings scattred
over skin near lid margin

103. Anamolies in position of
lashes and margin
 Trichiasis : inward misdirection of cilia with
normal position of lid margin.
 The inward turning of lid margin and lashes is
called pseudo trichiasis.
 Entropion :inturning of lid margin.
• Congenital
• Cicatrical
• Spastic
• Senile
• mechanical

104.  Ectropion : out rolling or outward turning of
lid margin.
1. Senile
2. Cicatrical
3. Paralytic
4. Mechanical
5. spastic

105.  Symblepharon :
 Condition in which lids become adherent with
the eye ball as a result of adhesions between
palpebral and bulbar tissue.
 Ankyloblepharon:
 Refers to adhesions between margins of
upper and lower lids.
 Congenital or acquired.
 Complete or incomplete.

106.  Blepharophimosis:
 The extent of palpebral fissure is decreased.it
appears contracted at outer canthus.
 Lagophthalmos:
 condition characterised by inability to close
the eye lids voluntarily.

107.  Ptosis :
 Abnormal drooping of upper eye lid.
 If more than 16 th of cornea is covered i.e.
>2mm
 Congenital
1. Simple congenital
2. Asso with weakness of superior rectus
3. Part of blepharophimosis syndrome
4. Congenital synkinetic ptosis.

108.  Acquired :
 Neurogenic
 Myogenic
 Aponeurotic
 Mechanical ptosis.

109.  Thank you.