ORIGINAL ARTICLES
OVERVIEW OF OCULOPLASTIC SURGERY
Eyelid Anatomy ROGER A. DAILEY, MD JOHN L. WOBIG, MD BACKGROUND. The following anatomic information concerning the complex structure of the eyelids is distilled from gross and histologic study as well as surgical experience. OBJECTIVE. Our aim is to familiarize the reader with eyelid anatomy. CONCLUSION. Appropriate shape, contour, height and mobility of the lids are essential to adequate protection and function of the eyes as well as overall appearance. A thorough understanding of eyelid anatomy is therefore necessary to achieve optimal surgical results. For the purpose of this discussion the eyelids can be divided into the following structural planes: 1) skin and subcutaneous tissue; 2)orbicularis muscle and submuscular fibroadipose layer; 3) orbital septum; a) preaponeurotic fat; 5)eyelid retractors; and 6) the tarsi and conjunctiva. J Dermatol Surg Oncol1992;18:10231027.
Skin and Subcutaneous Tissue The eyelid skin is less than 1 mm thick. The thin epidermis consists of statified epithelium of six to seven cell layers. The underlying dermis contains elastic fibers, blood vessels, lymphatics, and nerves. Beneath the dermis, the subcutaneous areolar tissue of the eyelids contains little or no fat. The hair follicles and pilosebaceous glands are located here. The nasal portion of the lids has finer hairs and more sebaceous glands than the temporal aspect, making this skin smoother and more oily.' Eccrine sweat glands are scattered throughout the eyelids and the apocrine Glands of Moll are located near the lid margin. The sebaceous Glands of Zeiss are associated with the follicles of the eyelashes. The eyelid crease is typically located at or near the superior border of the tarsus (Figure 1).The skin below the crease is firmly attached to the underlying tarsus via attachments of the levator aponeurosis. The aponeurosis has anterior projections through the pretarsal orbicularis to the skin and posterior connections to the inferior por-
From the Department of Ophthalmic Plastic andReconstructiae Surgery, Casey Eye Institute, Oregon Health Sciences Unioersity, Portland, Oregon. Address reprint requests to: Roger A. Dailey, MD, Ophthalmic Plastic and Reconstructiae Surgery, Casey Eye Institute, Oregon Health Sciences University, 3375 S.W. Terwiliger Boulevard, Portland, O R 97201-4197.
0 1992 by Elsevier Science Publishing Co., Inc. 0148-0812/92/$5.00
tion of anterior tarsus. Above the crease, the skin is more mobile because of its lack of superior aponeurotic attachments and relatively loose attachment to the underlying orbital septum. This allowsthe preseptal skin to overhang the crease creating the upper eyelid fold. Asian eyelids have a slightly different anatomic configuration, which produces a significant difference in the appearance of the lid. The orbital septum has been shown to fuse with the levator aponeurosis at a point much lower than in occidental lids.2This creates a much lower crease and allows the preaponeurotic fat to migrate more inferiorly producing a more prominent upper eyelid fold, which in some cases completely hides the pretarsal skin from view, creating the so-called single eyelid fold. The lower eyelid also has a transverse palpebral crease. It generally marks the inferior border of the tarsus. It begins 4 to 5 mm below the lash line medially and extends inferiorly and laterally in an oblique fashion.
Orbicularis Muscle and Submuscular Fibroadipose Layer The orbicularis muscle arises from the second branchial arch.3 The migration of the muscle is like a horseshoe, with the open ends inserting into the medial orbital wall. The orbicularis muscle is divided arbitrarily into orbital and palpebral portions; the palpebral portion is further divided into pretarsal and preseptal parts (Figure 2). The orbital portion extends beyond the orbital rim to overlie the frontalis, temporalis, and cheek musculature. Superiorly, the frontalis muscle terminates on the undersurface of the orbicularisunderneath the eyebrow. Medially, the corrugator supraciliaris and procerus muscles arise from the frontalis fibers. The corrugator inserts at the superomedial orbital rim. The procerus muscle inserts on the nasal bone. These two muscles act in concert and contribute significantly to facial expression. The orbital portion of the orbicularis has fibers that interdigitate with these muscles. The pretarsal orbicularis is located anterior to the tarsus to which it is firmly attached. The most superficial portion of the orbicularis is located at the lid margin and is termed the muscle of Riolan. Its location histologically corresponds to the grey line seen clinically.' The pretarsal muscle is securely bound between the levator aponeurosis and overlying skin by the anterior fibrous projections
1023
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1024 DAILEY AND WOBIG
1992;18:1023- 1027
Superior rerlus musrle
Mullet i muscle I Levalor
-Skin
Inferior rectus muscle
rior to the orbicularis oculi and frontalis muscles and anterior to the orbital septum. This submuscular fibroadipose layer is most well developed in the eyebrow, but may continue quite far inferiorly into the eyelid, nearly to the point where the orbital septum joins the levator aponeurosis.6 Fibrous septae within this fibroadipose layer become contiguous with more compact lamellae of the orbital septum posteriorly, imparting a multilayered quality to the orbital septum. This submuscular layer is also the location of the network of branches of the facial nerve and the maxillary division of the fifth cranial nerve. The facial nerve branches are oriented vertically in their course into the orbicularis' while the sensory nerves pierce the muscle to access the subcutaneous tissue. Scott et al,* in a recent article, felt that the vertically oriented fibers were sensory branches of the ophthalmic nerve and that the terminal branches of the facial nerve to the upper eyelid innervate the orbicularisoculi from the undersurfacein a horizontal orientation.
Inferior
oblique mu
Muller's muscle
Orbital Septum Figure 1. Cross section of upper and lower eyelids depicting structures in various layers. (From Putterman AM. Cosmetic Oculoplastic Surgey. New York: Grune and Stratton, 1982. lllustration by Linda A. Warren. Copyright 1982 by Grune and Stratton, lnc. Reprinted with permission from W.B. Saunders Company.)
of the levator. These projections are found from the crease down to the lid margin. The upper and lower pretarsal muscles give rise laterally to the lateral canthal tendon, which attaches to the lateral orbital tubercle. Eisler's pocket of adipose tissue is located anterior to the lateral canthal tendon and bounded anteriorly by the orbital ~ e p t u r nThe . ~ pretarsal muscles insert on the medial orbital wall via the medial canthal tendon. They also give rise to deep heads that extend behind the canaliculi and insert on the posterior lacrimal crest. The preseptal portion of the orbicularis, which overlies the septum, also inserts medially on the medial orbital wall. The superficial head of the upper and lower lid preseptal orbicularis muscle join with the medial canthal tendon while the deep heads insert in the fasica surrounding the lacrimal sac. Laterally, the preseptal muscle fibers are continuous, overlying the lateral canthal tendon. The submuscular fibroadipose layer is present poste-
The orbital septum is a mesodermal layer of the embryonic lid.9 It defines the anterior extent of the orbit and extends from the bony margin of the orbit, the arcus marginalis, toward the tarsus (Figure 3). In the upper lid, the septum attaches to the levator aponeurosis 2 to 5 mm (average 3.4 nun) above the superior border of the tarsus.6In the lower lid, the septum attaches to the inferior edge of the tarsus and it extends inferiorly to fuse
Figure 2. Orbicularis oculi muscle. (From Putterman AM. Cosmetic Oculoplastic Surgey. New York: Grune and Stratton, 1982. Illustration by Linda A. Warren. Copyright 1982 by Grune and Stratton, lnc. Reprinted with permission from W.B. Saunders Company.)
/
Pr"cer/ukorrugator
,Preseptal Orbicularis
'Orbicularis
1 Dermatol Surg Oncol
DAILEY AND WOBIG 1025 EYE ANATOMY
2992;28:1023-1027 Orbital septum \
Figure 3. Orbital septum. (From Putterman AM. Cosmetic Oculoplastic Surgery. New York Grune and Stratton, 2982. Illustration by Linda A. Warren. Copyright 2982 by Grune and
Stratton, lnc. Reprinted with permission from W.B. Saunders Company.)
with the periorbita at the orbital rim forming the dense band previously mentioned as the arcus marginalis. The septum is attached medially to the spine at the lower end of the anterior lacrimal crest, which is called the lacrimal tubercle. The septum extends from the lower lid to the upper lid medially by passing under the attachments of the medial orbicularis muscle at the posterior lacrimal crest. Laterally, the septum passes just anterior to the lateral canthal tendon and Eisler’s pocket. The septum forms the inferior border of the supraorbital notch and is pierced by the supratrochlearand infratrochlear neurovascular bundles superomedially. The posterior position of the orbital fat is maintained by the septum.
Preaponeurotic Fat The preaponeurotic fat is an excellent surgical landmark. It is found in the potential space immediately posterior to the orbital septum and anterior to the levator aponeurosis in the upper lig and anterior to the inferior retractors in the lower lid (Figure 4). The upper lid has two fat pads. nasal and central. The central fat pad is generally much larger while the nasal fat pad is slightly whiter in shade. The lower lid is believed to have three fat compartments: 1) a large central, 2) a small, slightly whiter nasal, and 3) a temporal fat pad. A second temporal fat pad has been proposed, lo however, whether this represents a truly separate fat compartment or is a deeper part of a single temporal fat pad is controversial. The fat is separated by thin fascia1 sheaths. Relatively large blood vessels are
Figure 1. Preaponeurotic orbital fat. (From Putterman AM.
Cosmetic Oculoplastic surgery. New York: Grune and Stratton, 2982. Illustration by Linda A. Warren. Copyright 2982 by Grune and Stratton, Inc. Reprinted with permission from W.B. Saundels Company.)
found in these areas, coursing through the connective tissue adjacent to the fat, as is the inferior oblique extraocular muscle, an elevator and extorter of the globe.
Eyelid Retractors The retractors of the eyelids are deep to the preaponeurotic fat and collectivelyserve to open the eyelids (Figure5). The origin of the upper lid retractors is at the apex of the
Figure 5. Levator aponeurosis and capsulopalpebral fascia. (From Putterman AM. Cosmetic Oculoplastic Surgery. New York Grune and Stratton, 1982. Illustration by Linda A. Warren. Copyright 2982 by Grune and Stratton, Inc. Reprinted with
permission from W.B. Saunders Company.) ,Suwrior transverse lkrament
is I
J Dermatol Surg Oncol 1992;18:1023 - 1027
1026 DAILEY AND WOBIG
Figure 6. Mdler 's muscle. (From Putterman AM. Cosmetic Oculoplastic Surgery. New York: Grune and Stratton, 1982. Illustration by Linda A. Warren. Copyright 1982 by Grune and Stratton, Inc. Reprinted with permission from W.B. Saunders Company.)
orbit from the undersurface of the lesser wing of the sphenoid bone. The levator palpebrae superioris overlies the superior rectus muscle. Near the level where the levator changes direction from a horizontal to a more vertical attitude at the superior transverse or Whitnall's ligament, the levator muscle divides into an anterior aponeurotic layer and a posterior superior tarsal muscle layer (Muller's muscle). The aponeurosisspreads medially and laterally to form the horns of the levator. The horns attach on their respective medial and lateral retinaculae. The lower end of the aponeurosis inserts into the lower third of the anterior surface of the tarsus. In addition, the aponeurosis is attached to the pretarsal muscle and skin by the previously mentioned anterior fibrous projections from the aponeurosis. The superior transverse, or Whitnall's ligament, extends from the lacrimal gland fossa laterally to the trochlea medially and is thought to act as a fulcrum and allow for the change in direction of the levator. It also has a suspensoryrole in the orbit and possibly acts as a check ligament of the levator muscle. The posterior division of the levator is the superior tarsal muscle or Muller's muscle (Figure 6). This smooth muscle is innervated by the cervical sympatheticsystem. Inferiorly, the muscle attaches to the superior margin of the upper lid tarsus. The lower lid retractors arise from the capsulopalpebra1 head given off by the inferior rectus muscle. This head extends anteriorly to split around the inferior oblique muscle and reunite anterior to this muscle as the inferior transverse ligament or Lockwoods ligament. The fascia1 tissue anterior to Lockwoods ligament is termed
the capsulopalpebral fascia. This fascia is the superiorposterior boundary of the orbital fat in the lower lid and extends anteriorly to fuse with the orbital septum and inserts on the lower border of the tarsal plate as well as the anterior and posterior surfaces. Some anterior projections of the fascia have been observed to penetrate the orbicularis muscle and probably contribute to the formation and maintenance of the lower eyelid transverse crease." Just posterior to the fascia is the sympathetically innervated inferior tarsal muscle (Muller's muscle). The smooth muscle fibers appear to terminate approximately 2.5 mm beneath the inferior tarsal border. A contribution from the capsulopalpebral fascia also extends posterior to the inferior tarsal muscle and inserts in the fomix to maintain this structure.
Tarsus and Conjunctiva The most posterior layers of the eyelids are the tarsus and conjunctiva (Figure 7). The tarsi are composed of dense irregular connective tissue and are responsible for the architectural form of the lids. The upper tarsus is approximately 29-mm long, and extends from the lateral commissure temporally to the punctum medially. The upper tarsus is 10 mm wide in the central lid and narrows medially and laterally. The lower tarsus is the same length as the upper tarsus, but is only 3.5 to 5-mm wide at the center of the lid. Each tarsus has numerous vertically oriented sebaceous glands referred to as Meibomian glands. Their orifices are located at the lid margin posterior to the eyelashes and the grey line.
Figure 7 . Tarsus and conjunctiva. (From Putterman AM. Cosmetic Oculoplastic Surgery. New York: Grune and Stratton, 1982. Illustration by Linda A. Warren. Copyright 1982 by Grune and Stratton, lnc. Reprinted with permission from W.B. Saunders Company.)
J Dermatof Surg Oncol 1992;18:1023 - 1027
The conjunctiva is very adherent to the underlying tarsus. The palpebral conjunctiva is that portion that is overlying the posterior aspect of the eyelid. It can be divided into marginal, tarsal, and orbital portions. The marginal conjunctivajoins with the skin at the lid margin. The tarsal conjunctiva is adherent to the tarsus. The orbital conjuctiva lies adjacent to the superior and inferior tarsal muscle. Once the conjunctiva has extended posteriorly past its reflection at the fomix, it becomes bulbar conjunctiva.
References 1. Warwick R. Eugene WOWSAnatomy of the Eye and Orbit, 7th ed. Philadelphia. WB Saunders, 1976. 2. Doxanas MT,Anderson RL. Oriental eyelids. An anatomic study. Arch Ophthalmol 1984;102:1232. 3. Jones LT, Wobig JL. Surgery of the eyelids and lacrimal system. Birmingham, AL Aesculapius Publishing 1976: 21 -22.
DAILEY AND WOBIG 1027
EYE ANATOMY 4. Wulc AE,Dryden RM, Khatchaturian T. Where is the gray line? Arch Ophthalmol 1987;105:1093-8. 5. Gioia VM,Linberg JV, McCormick SA. The anatomy of the lateral canthal tendon. Arch Ophthalmol 1987;105: 529-32. 6. Meyer DR, Linberg JV, Wobig JL, et al. Anatomy of the orbital septum and associated eyelid connective tissues. Ophthalmic Plast Reconstr Surg 1991;7104-13. 7. Jordan DR, Anderson RL. The facialnerve in eyelid surgery. Arch Ophthalm~l1989;1071114-5. 8. Scott KR, Tse DT, Kronish JW.Vertically oriented upper eyelid nerve fibers. Ophthalmol1992;99:222-6. 9. JonesLT, Reeh MT,WirtschafterJ. Ophthalmic Anatomy. Rochester, MN: American Academy of Ophthalmology, 197045-6. 10. Putterman AM. The mysterious second temporal fat pad. Ophthalmic Plast Reconstr Surg 1985;1:83-6. 11. Hawes MJ, Dortzbach RK. The microsopic anatomy of the lower eyelid retractors. Arch Ophthalmol 1982;lOO: 1313-8.
OVERVIEW OF OCULOPLASTIC SURGERY
Eyelid Anatomy ROGER A. DAILEY, MD JOHN L. WOBIG, MD BACKGROUND. The following anatomic information concerning the complex structure of the eyelids is distilled from gross and histologic study as well as surgical experience. OBJECTIVE. Our aim is to familiarize the reader with eyelid anatomy. CONCLUSION. Appropriate shape, contour, height and mobility of the lids are essential to adequate protection and function of the eyes as well as overall appearance. A thorough understanding of eyelid anatomy is therefore necessary to achieve optimal surgical results. For the purpose of this discussion the eyelids can be divided into the following structural planes: 1) skin and subcutaneous tissue; 2)orbicularis muscle and submuscular fibroadipose layer; 3) orbital septum; a) preaponeurotic fat; 5)eyelid retractors; and 6) the tarsi and conjunctiva. J Dermatol Surg Oncol1992;18:10231027.
Skin and Subcutaneous Tissue The eyelid skin is less than 1 mm thick. The thin epidermis consists of statified epithelium of six to seven cell layers. The underlying dermis contains elastic fibers, blood vessels, lymphatics, and nerves. Beneath the dermis, the subcutaneous areolar tissue of the eyelids contains little or no fat. The hair follicles and pilosebaceous glands are located here. The nasal portion of the lids has finer hairs and more sebaceous glands than the temporal aspect, making this skin smoother and more oily.' Eccrine sweat glands are scattered throughout the eyelids and the apocrine Glands of Moll are located near the lid margin. The sebaceous Glands of Zeiss are associated with the follicles of the eyelashes. The eyelid crease is typically located at or near the superior border of the tarsus (Figure 1).The skin below the crease is firmly attached to the underlying tarsus via attachments of the levator aponeurosis. The aponeurosis has anterior projections through the pretarsal orbicularis to the skin and posterior connections to the inferior por-
From the Department of Ophthalmic Plastic andReconstructiae Surgery, Casey Eye Institute, Oregon Health Sciences Unioersity, Portland, Oregon. Address reprint requests to: Roger A. Dailey, MD, Ophthalmic Plastic and Reconstructiae Surgery, Casey Eye Institute, Oregon Health Sciences University, 3375 S.W. Terwiliger Boulevard, Portland, O R 97201-4197.
0 1992 by Elsevier Science Publishing Co., Inc. 0148-0812/92/$5.00
tion of anterior tarsus. Above the crease, the skin is more mobile because of its lack of superior aponeurotic attachments and relatively loose attachment to the underlying orbital septum. This allowsthe preseptal skin to overhang the crease creating the upper eyelid fold. Asian eyelids have a slightly different anatomic configuration, which produces a significant difference in the appearance of the lid. The orbital septum has been shown to fuse with the levator aponeurosis at a point much lower than in occidental lids.2This creates a much lower crease and allows the preaponeurotic fat to migrate more inferiorly producing a more prominent upper eyelid fold, which in some cases completely hides the pretarsal skin from view, creating the so-called single eyelid fold. The lower eyelid also has a transverse palpebral crease. It generally marks the inferior border of the tarsus. It begins 4 to 5 mm below the lash line medially and extends inferiorly and laterally in an oblique fashion.
Orbicularis Muscle and Submuscular Fibroadipose Layer The orbicularis muscle arises from the second branchial arch.3 The migration of the muscle is like a horseshoe, with the open ends inserting into the medial orbital wall. The orbicularis muscle is divided arbitrarily into orbital and palpebral portions; the palpebral portion is further divided into pretarsal and preseptal parts (Figure 2). The orbital portion extends beyond the orbital rim to overlie the frontalis, temporalis, and cheek musculature. Superiorly, the frontalis muscle terminates on the undersurface of the orbicularisunderneath the eyebrow. Medially, the corrugator supraciliaris and procerus muscles arise from the frontalis fibers. The corrugator inserts at the superomedial orbital rim. The procerus muscle inserts on the nasal bone. These two muscles act in concert and contribute significantly to facial expression. The orbital portion of the orbicularis has fibers that interdigitate with these muscles. The pretarsal orbicularis is located anterior to the tarsus to which it is firmly attached. The most superficial portion of the orbicularis is located at the lid margin and is termed the muscle of Riolan. Its location histologically corresponds to the grey line seen clinically.' The pretarsal muscle is securely bound between the levator aponeurosis and overlying skin by the anterior fibrous projections
1023
J Dermatol Surg Oncol
1024 DAILEY AND WOBIG
1992;18:1023- 1027
Superior rerlus musrle
Mullet i muscle I Levalor
-Skin
Inferior rectus muscle
rior to the orbicularis oculi and frontalis muscles and anterior to the orbital septum. This submuscular fibroadipose layer is most well developed in the eyebrow, but may continue quite far inferiorly into the eyelid, nearly to the point where the orbital septum joins the levator aponeurosis.6 Fibrous septae within this fibroadipose layer become contiguous with more compact lamellae of the orbital septum posteriorly, imparting a multilayered quality to the orbital septum. This submuscular layer is also the location of the network of branches of the facial nerve and the maxillary division of the fifth cranial nerve. The facial nerve branches are oriented vertically in their course into the orbicularis' while the sensory nerves pierce the muscle to access the subcutaneous tissue. Scott et al,* in a recent article, felt that the vertically oriented fibers were sensory branches of the ophthalmic nerve and that the terminal branches of the facial nerve to the upper eyelid innervate the orbicularisoculi from the undersurfacein a horizontal orientation.
Inferior
oblique mu
Muller's muscle
Orbital Septum Figure 1. Cross section of upper and lower eyelids depicting structures in various layers. (From Putterman AM. Cosmetic Oculoplastic Surgey. New York: Grune and Stratton, 1982. lllustration by Linda A. Warren. Copyright 1982 by Grune and Stratton, lnc. Reprinted with permission from W.B. Saunders Company.)
of the levator. These projections are found from the crease down to the lid margin. The upper and lower pretarsal muscles give rise laterally to the lateral canthal tendon, which attaches to the lateral orbital tubercle. Eisler's pocket of adipose tissue is located anterior to the lateral canthal tendon and bounded anteriorly by the orbital ~ e p t u r nThe . ~ pretarsal muscles insert on the medial orbital wall via the medial canthal tendon. They also give rise to deep heads that extend behind the canaliculi and insert on the posterior lacrimal crest. The preseptal portion of the orbicularis, which overlies the septum, also inserts medially on the medial orbital wall. The superficial head of the upper and lower lid preseptal orbicularis muscle join with the medial canthal tendon while the deep heads insert in the fasica surrounding the lacrimal sac. Laterally, the preseptal muscle fibers are continuous, overlying the lateral canthal tendon. The submuscular fibroadipose layer is present poste-
The orbital septum is a mesodermal layer of the embryonic lid.9 It defines the anterior extent of the orbit and extends from the bony margin of the orbit, the arcus marginalis, toward the tarsus (Figure 3). In the upper lid, the septum attaches to the levator aponeurosis 2 to 5 mm (average 3.4 nun) above the superior border of the tarsus.6In the lower lid, the septum attaches to the inferior edge of the tarsus and it extends inferiorly to fuse
Figure 2. Orbicularis oculi muscle. (From Putterman AM. Cosmetic Oculoplastic Surgey. New York: Grune and Stratton, 1982. Illustration by Linda A. Warren. Copyright 1982 by Grune and Stratton, lnc. Reprinted with permission from W.B. Saunders Company.)
/
Pr"cer/ukorrugator
,Preseptal Orbicularis
'Orbicularis
1 Dermatol Surg Oncol
DAILEY AND WOBIG 1025 EYE ANATOMY
2992;28:1023-1027 Orbital septum \
Figure 3. Orbital septum. (From Putterman AM. Cosmetic Oculoplastic Surgery. New York Grune and Stratton, 2982. Illustration by Linda A. Warren. Copyright 2982 by Grune and
Stratton, lnc. Reprinted with permission from W.B. Saunders Company.)
with the periorbita at the orbital rim forming the dense band previously mentioned as the arcus marginalis. The septum is attached medially to the spine at the lower end of the anterior lacrimal crest, which is called the lacrimal tubercle. The septum extends from the lower lid to the upper lid medially by passing under the attachments of the medial orbicularis muscle at the posterior lacrimal crest. Laterally, the septum passes just anterior to the lateral canthal tendon and Eisler’s pocket. The septum forms the inferior border of the supraorbital notch and is pierced by the supratrochlearand infratrochlear neurovascular bundles superomedially. The posterior position of the orbital fat is maintained by the septum.
Preaponeurotic Fat The preaponeurotic fat is an excellent surgical landmark. It is found in the potential space immediately posterior to the orbital septum and anterior to the levator aponeurosis in the upper lig and anterior to the inferior retractors in the lower lid (Figure 4). The upper lid has two fat pads. nasal and central. The central fat pad is generally much larger while the nasal fat pad is slightly whiter in shade. The lower lid is believed to have three fat compartments: 1) a large central, 2) a small, slightly whiter nasal, and 3) a temporal fat pad. A second temporal fat pad has been proposed, lo however, whether this represents a truly separate fat compartment or is a deeper part of a single temporal fat pad is controversial. The fat is separated by thin fascia1 sheaths. Relatively large blood vessels are
Figure 1. Preaponeurotic orbital fat. (From Putterman AM.
Cosmetic Oculoplastic surgery. New York: Grune and Stratton, 2982. Illustration by Linda A. Warren. Copyright 2982 by Grune and Stratton, Inc. Reprinted with permission from W.B. Saundels Company.)
found in these areas, coursing through the connective tissue adjacent to the fat, as is the inferior oblique extraocular muscle, an elevator and extorter of the globe.
Eyelid Retractors The retractors of the eyelids are deep to the preaponeurotic fat and collectivelyserve to open the eyelids (Figure5). The origin of the upper lid retractors is at the apex of the
Figure 5. Levator aponeurosis and capsulopalpebral fascia. (From Putterman AM. Cosmetic Oculoplastic Surgery. New York Grune and Stratton, 1982. Illustration by Linda A. Warren. Copyright 2982 by Grune and Stratton, Inc. Reprinted with
permission from W.B. Saunders Company.) ,Suwrior transverse lkrament
is I
J Dermatol Surg Oncol 1992;18:1023 - 1027
1026 DAILEY AND WOBIG
Figure 6. Mdler 's muscle. (From Putterman AM. Cosmetic Oculoplastic Surgery. New York: Grune and Stratton, 1982. Illustration by Linda A. Warren. Copyright 1982 by Grune and Stratton, Inc. Reprinted with permission from W.B. Saunders Company.)
orbit from the undersurface of the lesser wing of the sphenoid bone. The levator palpebrae superioris overlies the superior rectus muscle. Near the level where the levator changes direction from a horizontal to a more vertical attitude at the superior transverse or Whitnall's ligament, the levator muscle divides into an anterior aponeurotic layer and a posterior superior tarsal muscle layer (Muller's muscle). The aponeurosisspreads medially and laterally to form the horns of the levator. The horns attach on their respective medial and lateral retinaculae. The lower end of the aponeurosis inserts into the lower third of the anterior surface of the tarsus. In addition, the aponeurosis is attached to the pretarsal muscle and skin by the previously mentioned anterior fibrous projections from the aponeurosis. The superior transverse, or Whitnall's ligament, extends from the lacrimal gland fossa laterally to the trochlea medially and is thought to act as a fulcrum and allow for the change in direction of the levator. It also has a suspensoryrole in the orbit and possibly acts as a check ligament of the levator muscle. The posterior division of the levator is the superior tarsal muscle or Muller's muscle (Figure 6). This smooth muscle is innervated by the cervical sympatheticsystem. Inferiorly, the muscle attaches to the superior margin of the upper lid tarsus. The lower lid retractors arise from the capsulopalpebra1 head given off by the inferior rectus muscle. This head extends anteriorly to split around the inferior oblique muscle and reunite anterior to this muscle as the inferior transverse ligament or Lockwoods ligament. The fascia1 tissue anterior to Lockwoods ligament is termed
the capsulopalpebral fascia. This fascia is the superiorposterior boundary of the orbital fat in the lower lid and extends anteriorly to fuse with the orbital septum and inserts on the lower border of the tarsal plate as well as the anterior and posterior surfaces. Some anterior projections of the fascia have been observed to penetrate the orbicularis muscle and probably contribute to the formation and maintenance of the lower eyelid transverse crease." Just posterior to the fascia is the sympathetically innervated inferior tarsal muscle (Muller's muscle). The smooth muscle fibers appear to terminate approximately 2.5 mm beneath the inferior tarsal border. A contribution from the capsulopalpebral fascia also extends posterior to the inferior tarsal muscle and inserts in the fomix to maintain this structure.
Tarsus and Conjunctiva The most posterior layers of the eyelids are the tarsus and conjunctiva (Figure 7). The tarsi are composed of dense irregular connective tissue and are responsible for the architectural form of the lids. The upper tarsus is approximately 29-mm long, and extends from the lateral commissure temporally to the punctum medially. The upper tarsus is 10 mm wide in the central lid and narrows medially and laterally. The lower tarsus is the same length as the upper tarsus, but is only 3.5 to 5-mm wide at the center of the lid. Each tarsus has numerous vertically oriented sebaceous glands referred to as Meibomian glands. Their orifices are located at the lid margin posterior to the eyelashes and the grey line.
Figure 7 . Tarsus and conjunctiva. (From Putterman AM. Cosmetic Oculoplastic Surgery. New York: Grune and Stratton, 1982. Illustration by Linda A. Warren. Copyright 1982 by Grune and Stratton, lnc. Reprinted with permission from W.B. Saunders Company.)
J Dermatof Surg Oncol 1992;18:1023 - 1027
The conjunctiva is very adherent to the underlying tarsus. The palpebral conjunctiva is that portion that is overlying the posterior aspect of the eyelid. It can be divided into marginal, tarsal, and orbital portions. The marginal conjunctivajoins with the skin at the lid margin. The tarsal conjunctiva is adherent to the tarsus. The orbital conjuctiva lies adjacent to the superior and inferior tarsal muscle. Once the conjunctiva has extended posteriorly past its reflection at the fomix, it becomes bulbar conjunctiva.
References 1. Warwick R. Eugene WOWSAnatomy of the Eye and Orbit, 7th ed. Philadelphia. WB Saunders, 1976. 2. Doxanas MT,Anderson RL. Oriental eyelids. An anatomic study. Arch Ophthalmol 1984;102:1232. 3. Jones LT, Wobig JL. Surgery of the eyelids and lacrimal system. Birmingham, AL Aesculapius Publishing 1976: 21 -22.
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