Eye lid anatomy

Eye lid anatomy for Ophthalmology residents, Oculoplasty fellows.

1. The Eye Lids Dr. Diwa Hamal OPAL, Fellow TIO

2. Early cell division: ( A ) fertilized ovum, ( B ) morula ( C ) blastula .

3. The facial processes. The frontalis muscle arises from the temporal lamina, whereas the orbicularis oculi, cor - rugator supercilii , and procerus muscles arise from the infraorbital lamina. Conjunctival mucous membrane is formed by a surface epithelium resting on a mesodermal substantia propria .

4. Eyelid development. ( A ) Eyelid fusion (8 to 10 weeks' gestation); ( B ) development of margin structures (3 to 4 months' gestation); eyelid dysjunction (5 to 6 months' gestation) .

5. Abnormalities Of Eyelid Development Congenital entropion Congenital ectropion Coloboma due to formation & pressure of amniotic bands or from failure of eyelids to fuse during embryonic life. Ptosis absence or fibrotic nature of levator palpebrae superioris Epiblepharon to a lack of deep anchoring of superficial skin to orbicularis oculi muscle. Cryptophthalmia Microblepharia Coloboma Ankyloblepharon Congenital ptosis Epiblepharon Euryblepharon Congenital entropion Congenital ectropion

6. Epicanthus palpebralis (also known as simple epicanthus). The amount of tissue above is the same amount as below the canthal angle. Epicanthus tarsalis . The epicanthal fold is more prominant in the upper eyelid. Blepharophimosis syndrome. The common triad of ptosis, horizontal shortening of the palpebral fissures, and epicanthus inversus (fold more prominent in lower lid) is seen .

7. Topography of eye lid A. Sagittal section of Asian eyelid anatomy. B . Sagittal section of Caucasian eyelid anatomy.

8. Concavity of superior orbital sulcus after enucleation of right eye. Convexity of superior sulcus from herniated orbital fat .

9. Langer lines ( A ) as they appear in a diagram and ( B ) clinically. These static skin lines are formed by collagenous, reticular, & elastic fibers in reticular dermis.

10. Gravitational lines formed by progressive thinning of relaxed skin.

11. Dynamic lines. Overaction of the procerus & corrugator superciliaris muscle create these frowns line in this patient with ocular phemigoid .

12. Structure of eye lid 12 Skin & Subcutaneous tissue Muscles of protraction Orbital septum & tarsal plates Orbital fat Muscle of retraction Conjunctiva

13. Skin of eye lid Skin of eyelid is thin. Fat is absent in pretarsal skin In preorbital & preseptal skin subcutaneous fat is sparse Pretarsal skin is firmly adherent to the underlying tarsus because of attachments of levator aponeurosis . Clinically, edema collects under loose preorbital & preseptal skin, leaving an identifiable border at pretarsal skin where there are denser subcutaneous fibroadipose attachments.

14. Eyelashes 14 The human eyes are protected and lined by eyelashes They are in 2-3 rows In upper eyelid(100-150) In lower lid(50-75) life span of 100-150 days. If the eyelash is pulled out or falls off, it will take as long as seven to eight weeks to grow back.

15. Glands of eye lid Meibomian glands : P resent in stroma of tarsal plate arranged vertically. About 30-40 in upper & 20- 30 in lower lid. They are modified sebaceous glands & their ducts opens at lid margin Glands of zeis : S ebaceous glands opens into eyelashe follicles Accessory lacrimal glands of Wolfring : P resent near upper border of tarsal plate Glands of Moll: Modified sweat gland situated near hair follicles or into duct’s of Zeis glands. They do not open directly into skin surface

16. Orbicularis oculi muscle , ( A) Orbital portion; ( B ) preseptal portion; ( C ) pretarsal portion.

17. Protractors Orbicularis oculi muscle Firmly attached to underlying lateral palpebral raphe , medial canthal region , insertions of upper & lower eyelid retractors , supraorbital ridge , naso -orbital valley & malar crease O rbital portion Superiorly- to eyebrow, where it interdigitates with frontalis & corrugator superciliaris Medially- extends from supraorbital notch in a curvilinear fashion over side of nose Laterally- extends to temporalis muscle Inferiorly - to infraorbital foramen. It continues along infraorbital margin These thick course fibers play an important role in voluntary lid closure (winking) & forced eyelid closure.

18. Preseptal Orbicularis Oculi It overlies orbital septum & in between is a fibroadipose layer If this post orbicularis layer contains a significant amount of fat , ptosis surgeon may misinterpret it as being preaponeurotic fat . Laterally- Whitnall’sl tubercle. Because of fibrous component of this lateral attachment, Jones misleadingly termed this lateral canthal tendon rather than lateral canthal ligament . Medially- lacrimal sac, its fascia, & lacrimal crests . Medial origin Deep head or Jones muscle is adherent to lacrimal sac & fascia S uperficial head arises from anterior rim of medial canthal ligament. Functionally, the preseptal fibers contribute to voluntary lid closure (winking) & involuntary lid closure (blinking).

19. Pretarsal Orbicularis Oculi It is firmly adherent to underlying tarsus & to superficial insertion of levator aponeurosis at superior tarsal border . The superficial head inserts on anterior lacrimal crest & anterior limb of medial canthal ligament. Superficial fibers also surround canaliculi . Contraction shortens canaliculi , forcing lacrimal fluid into lacrimal sac . Functionally, involuntary lid closure (blinking) is primarily responsibility of smaller pretarsal orbicularis fibers.

20. Pretarsal Orbicularis Oculi Medial origin Deep head, Horner's tensor tarsi muscle arises from 4 mm behind posterior lacrimal crest & from lacrimal fascia to insert medially on tarsi of upper & lower eyelids. It’s contraction pulls eyelid medially & posteriorly, allowing eyelids to follow & cover, convex globe. In addition, it’s lateral contraction on lacrimal diaphragm creates a negative pressure in lacrimal sac that draws tears from canaliculi .

21. Orbicularis Oculi Horner's & Jones muscles are essential for proper functioning of lacrimal pump Deep fibers medially & posteriorly are responsible for proper eyelid-to-globe apposition. Laterally orbital & preseptal fibers fuse over zygoma to form lateral palpebral raphe . Deep fibers of pretarsal orbicularis joins inferior & superior crux of lateral canthal ligament, which inserts on Whitnall's tubercle

22. Medial attachments of the Orbicularis O culi muscle.

23. Orbicularis Oculi 24 Nerve supply Temporal and zygomatic branches of facial nerve Antagonist muscles Orbital part frontal belly of occipitofrontalis muscle Palpebral part levator palpebrae superioris

24. Orbital Septum Discreet , well-defined structure arising from arcus marginalis Deep fascia of overlying orbicularis oculi muscle Multilayered structure Fibrous septa within submuscular fibroadipose tissue become contiguous with more compact lamellae of orbital septum, imparting a multilayered quality to orbital septum. Fat within fibroadipose layer anterior to orbital septum may be mistaken for preaponeurotic fat pad during eyelid surgery O rbital septum & levator aponeurosis joins 2 to 5 mm above superior tarsal border . The orbital septum directly adjoins posterior epimysium of orbicularis for about 1 to 5 mm before joining levator aponeurosis .

25. Orbital Septum The cross-sectional thickness of orbital septum through its parallel lamella varies but is less than 1 mm. It is thickest at the arcus marginalis laterally and is thinnest in lower lid medially. Medially, posterior orbital septal lamella are carried posteriorly by pretarsal orbicularis muscle, which inserts on posterior lacrimal crest. Superficial orbital septal fibers, as described by whitnall appear to cross & adhere to lacrimal fascia before reaching anterior lacrimal crest. At lateral canthus, orbital septum is also split; deep fibers insert at Whitnall's tubercle, whereas superficial fibers join at lateral canthal raphe, just deep to orbicularis muscle.

26. Orbital Septum Variation in septal strength is seen between individuals & varies with age. Clinically , weakness of septum explains medial upper lid bulge ( bourrelet senile) seen in older patients & due to herniation of medial fat pad through an attenuated septum. It also may explain high incidence of orbital invasion of basal cell carcinoma in medial canthal region.

27. Lower lid O rbital Septa Arises from inferior orbital rim as a condensation of periosteum & periorbita . A nteriorly & superiorly to a point 4 to 5 mm below inferior tarsus, where it joins with lower eyelid retractors & as a single structure inserts on lower border of inferior tarsus . Medially orbital septum splits & is carried posteriorly by pretarsal orbicularis muscle (Horner's muscle ) & attaches to posterior lacrimal crest. Laterally, orbital septum also splits & is carried deep by insertion of orbicularis. The orbital septa of upper & lower eyelids form an anatomic barrier between preseptal & orbital structures. Infectious processes anterior to septa are considered to be more benign than posterior to septa. Functionally, suborbicularis oculi fibroadipose layer & multilayered orbital septum change with movement, enhancing eyelid & eyebrow mobility.

28. Structure piercing orbital septum Anastomosis between the angular and ophthalmic veins

29. Orbital fat p ad S erve as a protective cushion within which eyeball moves Fat within muscle cone is termed central or conal Fat outside muscle cone is termed peripheral or extraconal The whitish medial fat pad is more fibrous, whereas larger central fat pad is more yellow because of a decreased amount of fibrous tissue Larger central fat pad is termed preaponeurotic fat pad. T rochlea separates two fat pads . Clinically, preaponeurotic fat pad lies directly on the surface of muscular portion of levator & serves as an important surgical landmark to levator aponeurosis immediately beneath it

30. Orbital fat pad P reaponeurotic fat pad is less vascular than other fat pads. M edial fat pad is more vascular because of location of palpebral arterial arcade, which serpiginously courses through this pad Lateral to preaponeurotic fat pad lies lacrimal gland, which is typically pinker in appearance, firmer in texture , & distinctly more vascular than preaponeurotic fat pad During removal of orbital fat , eyelid surgeon is careful to avoid injury to laterally located lacrimal gland. In lower eyelid, there exists a smaller temporal fat pad & a larger medial fat pad . Temporal fat pad lies inferior to lateral canthus. It is separated from larger medial fat pad by a fibrous extension from periorbita & orbital septum infralaterally , joining with capsulopalpebral fascia & Lockwood's ligament

31. Orbital fat pad The lower eyelid fat pads are in direct communication with deeper extraconal fat of orbit. Clinically , this is important during lower eyelid surgery because excessive traction may be transmitted deeper into orbit, resulting in intraoperative or postoperative orbital hemorrhage. During transconjunctival lower eyelid blepharoplasty , lateral eyelid fat pad tends to be more fibrotic & prolapses less easily. Care is also taken to avoid inferior oblique muscle, which originates just lateral to ostium of nasolacrimal canal.

32. LPS Origin- At the orbital apex from lesser wing of sphenoid bone, superolateral to optic foramen At the level of superior tarsal border , fused lamellae of orbital septum & levator aponeurosis sends connective tissue attachments to secondarily insert onto overlying orbicularis oculi muscle & subcutaneous tissue. These attachments result in a sharp upper eyelid crease. Variations in these attachments result in variations in the location of the upper eyelid crease . The levator aponeurosis then sends connective tissue attachments, which insert primarily on the anterior inferior third of the superior tarsus, with the strongest attachments 3 mm from the lid margin It is these tarsal attachments that are more important for proper upper eyelid function.

33. Retractors upper lid LPS Triangular shaped striated muscle . Muscular portion -36 mm. Aponeurosis - 18 mm At the level of globe, levator muscle fans out & thins as whitish gray superior transverse ligament of Whitnall . Anteriorly , aponeurosis expands horizontally to insert onto medial & lateral retinacula as “horns” Medial horn of levator attaches to medial canthal ligament. lateral horn of levators splits lacrimal gland into larger orbital lobe & smaller palpebral lobe. It then attaches to lateral orbital tubercle by lateral canthal tendon & may provide suspensory support for gland. Aponeurosis continues anteriorly to a point 2 to 5 mm above the superior tarsal border, where it joins with fibers orbital septum Motor innervation of the levator muscle is the superior division of the oculomotor nerve (cranial nerve III).

34. Retractors upper lid Mullers (superior tarsal muscle) Müller's muscle takes its origin from underside of levator muscle 22 mm above superior tarsal border where it inserts. It is loosely adherent to the conjunctiva & more adherent near tarsus Innervated by sympathetic nerve, pierced by peripheral arterial arcade & other small arteries Clinically , increased sympathetic stimulation (as seen in Graves' disease) is thought to be a factor in thyroid eyelid retraction

35. Retractors lower lid Capsulopalpebral fascia Posterior to globe, a fibrous extension arises from inferior rectus muscle C ollectively termed capsulopalpebral head of inferior rectus muscle that splits to surround the inferior oblique muscle It has no inherent innervation but its action mirrors action of inferior rectus muscle, which is innervated by inferior division of oculomotor nerve. External portion is termed capsulopalpebral fascia I nner counterpart that contains smooth muscle is termed inferior tarsal muscle The two layers fuse anterior to inferior oblique muscle to form a dense fibrous structure termed Lockwood's suspensory ligament.

36. Retractors lower lid I nferior tarsal muscle It consists of numerous discontinuous smooth muscle bundles & becomes totally fibrous as the inferior tarsus is approached It is sympathetically innervated. Clinically, in Horners ' syndrome, the atonic muscle may allow lower eyelid to elevate as much as 1 mm. Conversely , in thyroid eye disease, the lower eyelid may retract from increased sympathetic tone. Thyroid lid retraction. Sympathetic stimulation of Müller's muscle & inferior tarsal muscle is a factor in this patient with Graves' disease.

37. The upper & lower tarsal plates. T hickened fibrous connective tissue that provide structural support to the eyelids. Medially and laterally, the tarsal plates are connected to bony orbital margins by ligamentous fibrous tissue S uperior tarsal plate is 10 mm in vertical height and 25 to 30 mm in horizontal dimension. 30 to 40 vertically meibomian glands are present I nferior tarsal plate is 3 to 5 mm in vertical height and measures 25 to 30 mm horizontally . 20 to 30 vertically oriented meibomian glands are present

38. Suspensory system of the eyelids Whitnall's ligament Lockwood's ligament Lateral canthal ligament Medial canthal ligament Eyelid margin

39. Suspensory System Of The Eyelids S uperior transverse ligament of Whitnall Main suspensory ligament of upper eyelid & as a check ligament for levator aponeurosis & muscle S uperior conjunctival fornix suspension assisted by curvature of globe, It is suspended from periorbita of orbital roof, extending medially from trochlea across horizontal dimension of orbit to frontozygomatic suture, 10 mm superior to Whitnall's orbital tubercle Laterally , it sends weaker attachments to Whitnall's tubercle . Clinically, this is an important structure encountered frequently during eyelid surgery.

40. . The most significant lateral attachment site of Whitnall's ligament is at frontozygomatic suture Whitnall's ligament is found 15 to 20 mm superior to the superior border of the tarsus as a white, shiny, glistening structure where the levator muscle becomes an aponeurosis

41. Suspensory System Of E yelid Lockwood's Ligament It acts as a suspensory hammock for globe even if all bone inferior to its attachments at medial & lateral orbital walls are removed. O uter fibers of capsulopalpebral fascia fuse with inner fibers of inferior orbital septum 4 to 5 mm below inferior tarsus & together advance as a single layer to insert on inferior border of inferior tarsus Serves as an anchor for inferior conjunctival fornix It is composed of thickened Tenon's capsule, intramuscular septa, check ligaments, fibers from inferior rectus sheath, lower lid retractors. Medially it iattaches to medial canthal ligament and laterally to lateral canthal ligament .

42. Suspensory System Of Eyelid Medial Canthal Ligament/tendon- Aids in function of lacrimal pump. Anterior limb is a broad fibrous structure that attaches eyelids to frontal process of the maxillary bone & to anterior lacrimal crest. It gives origin to superficial head of pretarsal orbicularis oculi muscle. Posterior limb of medial canthal ligament inserts on posterior lacrimal crest and lacrimal fascia. Lateral Canthal Ligament/ tendon- S uperior crux from superior tarsus & an inferior crux from inferior tarsus they fuse at the lateral border of tarsal plates to join lateral retinaculum, a condensation of several anatomic structures that inserts onto lateral orbital tubercle of Whitnall .

43. Anterior limb of medial canthal ligament. In this cadaver dissection, the anterior limb of the medial canthal ligament ( arrow ) is seen originating from the frontal process of the maxillary bone ( pointer ). Forceps reflect the medial aspect of the eyelid .

44. Conjunctiva C onjunctiva represents differentiated inner portion of skin fold that forms eyelid. It is composed of nonkeratinized stratified squamous epithelium with goblet cells. P alpebral conjunctiva is loosely adherent, except at tarsus & at superior tarsal muscle where it is tightly adherent. In lower eyelid , conjunctiva is adherent to lower tarsus but can be elevated from lower eyelid retractors without difficulty.

45. Arterial Supply Deep / Intraorbital System Lacrimal - Lateral eye lid- LPA Supraorbital - Upper eye lid, Levator , Forehead Supratrochlear - Forehead Dorsal nasal - MPA Z ygomatico -orbital branch of superficial temporal artery

46. Arterial Supply Superficial / Facial System Facial artery continewes as angular artery it lies within orbicularis oculi muscle 6 to 8 mm medial to medial canthus & 5 mm anterior to lacrimal sac. Anastomose with dorsal nasal branch of ophthalmic artery. S uperficial temporal artery ( ECA) gives off 3 branches to supply eye lid. Frontal branch- frontalis muscle of forehead & orbicularis oculi anastomosing with lacrimal & supraorbital arteries Zygomatico - orbital- upper eyelid, anterior orbit Transverse facial- supply malar region & lateral aspect of lower eyelid to anastomoses with lacrimal & infraorbital arteries I nfraorbital arteries - rich contribution to lower eyelid (internal maxillary artery)

47. Forehead, eyebrow & upper eyelid frontal vein supraorbital vein deep to orbicularis oculi into ( angular & supraorbital veins ) superior ophthalmic v Leaves orbit near annulus of Zinn by SOF I nferior ophthalmic vein begins as a plexus near anterior aspect of orbital floor receives blood from lower eyelid, lacrimal sac, IR muscle, IO muscle, 2 inferior vortex veins Deep v enous system Other branches of deep orbital system…. central retinal vein , anterior ciliary veins, & cavernous sinuses. receives venous drainage from superior vortex veins cavernous sinus pterygoid plexus by IOF

48. Superficial venous system superior ophthalmic vein superficial frontal vein from the forehead Posterior facial v common facial v IJV Superiorly & laterally, venous blood from forehead , eyebrow & eyelid drain from supraorbital vein into superficial temporal vein , into EJV EJV

49. FACIAL LYMPHATIC SYSTEM. Deep parotid Deep cervical nodes IJV

50. Oculomotor N- Sup dev - SR, LPS Inf dev - MR,IR,IO,parasym twig to ciliary ganglion Trigeminal N- Ophthalmic Lacrimal- lateral eye lid, forhead Frontal- Supra orbita - skin of eye lid, forheadl & supratrochlear medial commissure, middle of forehead. Nasociliary - (1) the long sensory root of the ciliary ganglion; (2) the long ciliary nerves, (3) the infratrochlear nerve, which is sensory to the medial canthus (4) the posterior ethmoidal nerve Maxillary Infraorbital nerve- skin & conjunctiva of lower eyelid, Sensory innervation. Sensation to the upper lids is provided by the first division of cranial nerve V, whereas the lower lid is by the second division.

51. Facial Nerve Temporal Zygomatic Buccal orbicularis oculi muscle procerus corrugator muscles

52. Sympathetic supply Causes vasoconstriction , smooth muscle function, hidrosis , pupillary dilation , pilomotor and sweat gland function of skin of face. A rise from carotid plexus & enter cavernous sinus sheathing intracavernous carotid artery. Within cavernous sinus, sympathetic fibers join nerve branches & arteries entering the orbit. Sympathetic innervation may reach tarsal muscles through a combination of roots: with (1) levator muscle, (2) marginal vascular arcades, (3) perivascular plexus of arterioles of muscles, (4) motor nerves of the ocular motor muscles, or (5) sensory nerves. Clinically, interruption of sympathetic nerve fibers may result in Horner's syndrome, with vascular dilation, ptosis, anhidrosis , miosis , & heterochromia .

53. Forehead T ransverse elevation of superciliary ridge of frontal bone layer consists- skin, subcutaneous connective tissue , muscular layer, submuscular areolar layer & pericranium S kin is thick & mobile contains sebaceous glands S ubcutaneous tissue layer has more fibrous tissue than fat Muscular layer V ertical fibers of frontalis H orizontal fibers of orbicularis oculi O blique fibers of corrugator supercilii

54. Forhead …. Frontalis Origin- Galea aponeurotica Insertion- Orbicularis oculi Action- Raises eyebraws , wrinkles forehead skin Artery- Supraorbital, Supratrochlear Nerve- Facial(Temporal )

55. Forehead…. C orrugator supercilii muscle Origin - frontal bone near superomedial orbital margin Insertsion - at muscle, skin behind & immediately superior to middle third of eyebrow Procerus muscle Origin- from nasal bone & upper nasal cartilage Insertion- on medial forehead skin D epressor supercilii muscle Origin- frontal potion of maxillary bone Insertion- on skin superior to medial canthal tendon Frontalis muscle & orbicularis interdigitate in eyebrow, a unique feature in superficial muscle plane of face Brow muscle force vectors. Open arrows depict upward muscular force vectors and solid arrows depict downward muscular force and gravity.

56. Age related changes (1) photo-induced aging or ultraviolet (UV) damage, (2) mechanical influences such as gravity and muscle contraction, and (3) chronologic or intrinsic aging changes . Skin changes are characterized clinically by elastosis , irregular pigmentation, roughness or dryness, teleangiectasia , atrophy, deep wrinkling, and a variety of neoplasms . Mechanical influences from gravity and contraction of the muscles of facial expression cause a decrease in skin elasticity resulting from constant stretch and tension. Chronologic skin aging is the histologic and physiologic changes seen in sun-protected skin of most older individuals. Clinical changes seen in the skin are laxity, dryness, and fine wrinkling.

57. Age related changes Eyebrow ptosis Synophrys - hypertrophy of eyebrows result in fusion at midline glabellar area levator aponeurosis may become infiltrated with fat & disinsert from tarsus compensatory brow arching Involutional lid ptosis H orizontal lid laxity- ectropion or entropion T elangiectasias , lid thickening, hyperkeratinization & meibomian gland orifice changes D ecrease in amplitude & peak velocity of closure phase of both spontaneous & voluntary blinks. N arrowing of palpebral fissure with age. However, it may also be partially because of a reduction in dopamine levels with age.

58. THANK YOU

59. References… Embryology & Anatomy of the Eyelid. Edward H. Bedrossian , JR. Eyebrows, Eyelids, & Face: Structure & Function. Michael s. Mccracken , Jonathan d. Del Prado, & Don O. Kikkawa . Oculoplastic Surgery. Second Edition. Brian Leatherbarrow . Smith & Nesi’s Ophthalmic Plastic & Reconstructive Surgery.