Eyelid recon
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Transcript of Eyelid recon
Eyelid Anatomy/Reconstruction
Eyelid
• Thin skin, areolar tissue, orbicularis occuli ms., tarsus, levator palpabrae superioris, Muller’s ms., septum orbitale, fat and conjunctiva
• Skin – thin, elastic, moderately adherent to orbicularis over the tarsus, becomes more loose and mobile in the preseptal and orbital regions
• Becomes thicker at the junction of the skin of the cheek and eyebrow at the bony orbital margin
Embryology
• 2 ectodermal folds containing a core of mesenchyme
• Ectoderm: eyelashes and lacrimal glands• Mesoderm: muscles & tarsal plate
Blood Supply
• Via marginal & peripheral arcades– Upper marginal arcade - via ophthalmic artery– Lower marginal arcade - via facial artery branches– Medial peripheral network - via anastomosis from
ICA & ECA systems– Lateral peripheral network - via branches of STA &
lacrimal artery
Innervation
• Periorbital sensation : V1 & V2 branches• Orbicularis: temporal & zygomatic branches of
facial nerve
Eyelid Cross Section
Orbicularis oculi
• Surrounds the palpaberal fissure • Responsible for lid closure • Divided into palpebral & orbital regions• Palpebral region subdivided into pretarsal &
preseptal parts
Orbicularis oculi
Orbital Septum
• Facial membrane which separates the eyelid structures from the deep orbital structures
• Barrier that helps prevent the spread of hemorrhages, infection, inflammation
• Attaches to the orbital margin at a thickening of the periosteum called the arcus marginalis
• Arcus is also the point of confluence of the facial bones periosteum and the periorbita
Orbital Septum
• Upper lid: OS inserts onto the levator aponeurosis 2-5mm above the superior portion of the tarsus
• Lower lid: OS inserts into the lower edge of the tarsus
Orbital Septum
• Laterally: OS anterior to the lateral canthal ligament• Medially: OS posterior to Orbicularis oculi & anterior to
Superior oblique/Trochlear pulley & inserts into the posterior lacrimal crest
• Superomedially: AM forms the inferior part of the supraorbital groove
• Inferomedially: OS attaches to the anterior lacrimal crest & inferior orbital rim
• Recess of Eisler: potential space along the lateral half of the orbital rim where OS originates just inferior to the orbital margin
Orbital Septum
Medial Canthus
• Tripartite apparatus:– Vertical component -
suspension & fixation of the medial canthus
– Horizontal components contribute little to stability
Lateral Canthus
• Attaches to: upper & lower tarsal plates, orbicularis oculi, fibrous portion of OS
• Inserts to: lateral orbital tubercle of Whitnall (5mm behind the rim)
Tarsal plates
• Thin elongated plates of connective tissue
• Contribute to form and support the eyelids
• Closely related to the LPS, medial, lateral canthal structures
• Superior tarsus 10-12mm tapering to the sides. Inferior tarsus 3.8-4.5 mm
• The meibomian glands are approx 20 in each lid within the substance opening in a row of tiny dots corresponding to the Grey line – mucocutaneous junction
Pre-aponeurotic fat
Upper eyelid retracters
Levator palpebrae superioris
• Striated muscle (CN III)
• Origin: lesser wing of sphenoid anterior to the optic foramen
• Length: 40-45mm (including 10-15mm aponeurotic extension)
• Aponeurosis attaches to the lower 7-8mm of the anterior tarsus & sends fibres through the orbicularis to the skin - upper lid crease
• Total excursion 10-15mm
Muller’s muscle
• Smooth muscle (sympathetic)
• Posterior to levator
• Length 10mm & inserts into tarsal plate
• Excursion 2-3mm
• Horner’s syndrome
Lower eyelid retractors
• Capsulopalpebral head of the inferior rectus
• Muller’s muscle
Conjunctiva
• Marginal: lid margin to anterior skin
• Tarsal: adherent to the tarsus
• Orbital: posterior to Muller’s muscle
• Bulbar: extends posterior to the fornix
Lacrimal system• Controls the tear secretion • Basic and Reflex secretors• Basic secretors – three sets of glands
Limbal: mucus secreting goblet cells – produce a mucoprotein layer covering the corneaConjunctival: Accessory lacrimal glands of Krause and Wolfring located in the s/c tissue Tarsal: Oil producing Meibomian glands and the
palpaberal glands of Zeis and Moll. Outermost precorneal lipid layer helps stabilize the tear film and retards evaporation
• Reflex Secretors - main lacrimal gland (orbital & palpebral lobes)
Lacrimal system
Lacrimal drainage system
• Upper and Lower puncta open 5-7 mm from the canthal angle at the apex of the papilla
• Ampulla – vertical portion of the canaliculus – dilated portion just prior to the transition to a horizontal direction
• Horizontal portion measures approximately 8mm and converge to form the common canaliculus to enter the sac, may enter separately
• Lacrimal sac is located in the lacrimal fossa just posterior to the medial canthal tendon
• Nasolacrimal duct passes downward inferiorly to open into the inferior meatus
Lacrimal drainage system
Eyelid Reconstruction
• Aims:– To reestablish functional eyelids– Adequate protection of the eyeball– Reasonable cosmesis
Eyelid Reconstruction
• Requirements:– Smooth mucous membrane internal lining to maintain lubrication of
the ocular surface and avoid corneal irritation– Skeletal support to provide adequate lid rigidity and shape but also
allow molding to the globe– Stable eyelid margin to keep eyelashes & skin away from cornea– Proper fixation of the medial & lateral canthal attachments of the lids
for eyelid stability & orientation– Adequate muscle to provide tone & power for closure– Supple, thin skin to allow eyelid excursion– Adequate levator action to lift the upper lid above the visual axis
Eyelid Reconstruction
• Anterior & Posterior lamella• Anterior lamella:– Skin & orbicularis oculi– Dynamic closure of upper & lower lids– Lacrimal pump mechanism
• Posterior lamella:– Tarsal plates – Conjunctival lining
Eyelid Reconstruction
• Anterior lamella:– Flaps - advancement, transposition, or rotational
musculocutaneous flaps– Full thickness skin grafts
Eyelid Reconstruction
• Posterior lamella:– Tarsal-conjunctival transposition, advancement or
rotational flap– Free autogenous composite tarsal grafts– Tarsal substitute grafts - sclera, nasal septal
chondromucosa, hard palate mucosa
Eyelid Reconstruction
• In the reconstruction of both anterior & posterior lamellae, at least one must have its own blood supply
• Techniques would depend on the size, location, configuration, & depth of the defect
• Superficial defect: only anterior lamella needs to be repaired
• Full thickness defect: needs reconstruction of both layers
Mustarde Flap-Cheek rotation-Deep eyelid defects >75%-Often problems with sagging lower lid, ectropion, entropion, epiphora, flap necrosis, facial nerve injury.
Can close defects up to 25-50% directly +/- Canthol release.
Approximate Margin first, if tight then proceed to:
Lateral Canthotomy
Inferior Cantholysis
Tenzel Slide-Up to 70% defects of lower eyelid
-best if tarsal plate remnant at each end
-good in elderly with poor other eye
-McGregor Flap is similar but incorporates a Z-Plasty
Hughes (TarsoConjunctival Flap)-“Like with like”-Shallow defects up to 100% of margin-4mm Tarsus needed for stability- Need good other eye!
SOURCE OF CHONDRO- MUCOSAL GRAFT
Hughes Flap(For Posterior
Lamella)
FTSG(For Anterior
Lamella)
Tripier Flap-Shallow defects up to 100% of lower lid-Can be lined or unlined-But, Tendency to sag and for margin to retract-Medially, Laterally or Bipedicle-?Treacher Collins Coloboma
Reverse Hughes-No support but ?good results
-Note: Another type of flap good for up to 70% of margin is the upper lid horizontal advancement tarsoconjunctival flap with a skin graft.
Cutler-Beard 1955-up to 100% of eyelid margin, divide at 8 weeks
-Incision 4 to 6mm below lid margin-Lacks support, modify with ear cartilage deep to orbicularis
Mustarde Lid Switch-Laterally based is unreliable
-Medially based is a 2 stage procedure
Full Thickness Skin Graft harvested from left preauricular area