Download Lacrimal glands

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解剖學科
鄭授德
本教材之圖片取自於
1. Gray’s Anatomy for Students, 3rd ed., 2015, by Drake, Vogl, and Mitchell
2. Clinically Oriented Anatomy, 7th ed., 2014, by Moore, Dalley, and Agur
3. Anatomy, an Essential Textbook, 2013, by Giloroy, Voll, and Wesker
4. Clemente Anatomy, A Regional Atlas of the Human Body, 1997, 4th ed
5. Gray’s Anatomy, the Anatomical Basis of Clinical Practice, 2008, 40th ed.
Bony orbit
• Sup.
– frontal bone
• Med.
– frontal process of maxilla
• Inf.
– zygomatic process of maxilla
– zygomatic bone
• Lat.
– frontal processes of zygomatic
bone
– zygomatic processes of frontal
bone
Roof
• Frontal and sphenoid bones (lesser wing); anterior
cranial fossa is above the roof
• Anteromedially – frontal sinus, trochlear fovea
• Anterolaterally – lacrimal fossa
Medial wall
• By maxilla, lacrimal, ethmoid, and
sphenoid bones
• Ethmoid air cells, frontoethmoidal
suture, anterior and posterior
ethmoidal foramina (for ant. and post.
ethmoidal nn. and vessels)
• Lacrimal bone
• Lacrimal groove (with posterior
lacrimal crest of lacrimal bone, and
anterior lacrimal crest of maxilla)
• Optic canal on the sphenoid bone
Floor
• also the roof of maxillary sinus,
contains maxilla, zygomatic, and
palatine bones
• Inferior orbital fissure
separates the inferior wall from
lateral wall.
Lateral wall
• zygomatic bone and greater
wing of sphenoid bone
Eyelids
• Palpebral fissure between upper and lower eyelids
1. Skin and subcutaneous tissue
•
ST may accumulate blood under injury
2. Orbicularis oculi
3. Orbital septum
– Extension of periosteum in
upper and lower eyelids
– Attaches to the tendon of levator
palpebrae superioris m. and tarsus
of lower eyelid
4. Tarsus and levator palpebrae superioris
5. Conjunctiva
– reflects onto sclera as superior and inferior conjunctival fornices.
– Conjunctival sac is formed when eyelids close.
Orbicularis oculi
• innervated by CN VII
1. Palpebral part: in eyelids
– Medial palpebral ligament to ant. lacrimal crest
– Lateral palpebral ligament to zygomaitc bone
Orbital part: around orbit
2.
3. Lacrimal part:
– medial end, attaches to
post. lacrimal crest
– drains tears
Tarsus
• Superior tarsus and inferior tarsus
– attach through medial palpebral ligament to anterior lacrimal
crest of maxilla
– attach through lateral palpebral ligament to zygomatic bone
• Tarsal glands
– embed in the tarsal plates, and open to the free margin of eyelids
Levator palpebrae superioris
• Levator palpebrae superioris muscle
O: post. part of the roof of orbit, sup. to optic foramen
I: ant. surface of superior tarsus
F: raises upper eyelid
N: CN III
• Superior tarsal muscle
O: inferior surface of levator palpebrae superioris
I: upper edge of superior tarsus
F: assists to maintain upper eyelid
elevation
N: sympathetic fibers from
superior cervical ganglion
• Loss function of either of these
two muscles causes drooping
of upper eyelid (ptosis)
Glands
• Sebaceous glands and sweat glands
– associated with eyelash
– blockage and inflammation cause
stye (麥粒腫、針眼) on the
edge of eyelids
• Tarsal glands
– opening on the edge of eyelids
– blockage and inflammation cause
chalazion (霰ㄒㄧㄢˋ粒腫) on the
inner surface of eyelids
Vessels
1. Ophthalmic a. –
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Supratrochlear a.
Supra-orbital a.
Lacrimal a.
Dorsal nasal a.
2. Facial a.
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Angular a.
3. Superficial temporal a.
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Transverse facial a.
4. Brr. of superficial temporal a.
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Ext. venous drainage with associated aa.
Int. venous drainage to ophthalmic vv.
Lymph drainage to parotid primarily, and (medial corner
of orbit to) submandibular nodes
Innervation
• Sensory:
– Supra-orbital, supratrochlear,
infratrochlear, lacrimal brr. of CN V1
– Infra-orbital br. of CN V2
• Motor:
– CN VII – palpebral part of orbicularis
oculi (unable to close eyelid tightly)
– CN III – levator palpebrae superioris
(complete ptosis)
– Sympathetic ff. – superior tarsal m.
(partial ptosis)
• Horner’s syndrome
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Lesion on sympathetic trunk in neck
pupillary constriction(縮瞳)
partial ptosis(垂瞼)
absence of sweating(乾)
vasodilation(結膜紅)
endophthalmos(眼球下陷)
Lacrimal apparatus
•
Lacrimal glands and ducts:
– Orbital part: in lacrimal fossa of frontal bone
– Palpebral part: inferior to levator palpebrae superioris
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Lacrimal lake
– medial end of conjunctival sac
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Lacrimal punctum
– opening of lacrimal canaliculus
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Lacrimal canaliculi
– drain to lacrimal sac
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Lacrimal sac
– between medial palpebral ligament and
lacrimal part of orbicularis oculi m.
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Nasolacrimal duct
– drain to inferior meatus of nasal cavity
Innervation
1. Sensory innervation
Lacrimal br. of CN V1
2. Secretomotor (parasympathetic) innervation
Preganglionic parasympathetic ff. in CN VII > Greater petrosal n. >
N. of pterygoid canal > Pterygopalatine gang. (synapse) >
Postganglionic ff. > Maxillary n. > Zygomatic n. >
Zygomaticotemporal n. > Lacrimal n. > Lacrimal gland
Innervation
3. Sympathetic innervation
Superior cervical gang. > Postgang. sympathetic ff. >
Plexus surrounding int. carotid a. > Deep petrosal n. >
N. of pterygoid canal >
Pass through pterygopalatine ganglion >
same as postganglionic parasympathetic ff. > > >
Lacrimal gland
Fissures and foramina
• Optic canal
– Between body and lesser wing of
sphenoid bone
– passed by optic n. (CN II) and
ophthalmic a.
• Superior orbital fissure
– Between roof and lateral wall of orbit
– passed by CN III (superior and inferior
brr.), CN IV, CN VI, and CN V1
(lacrimal, frontal, and nasociliary brr. of
ophthalmic n.)
Fissures and foramina
• Inferior orbital fissure
– Between lateral wall and floor
– Connects orbit with pterygopalatine
fossa
– passed by maxillary n. and zygomatic
br., and vv. to pterygoid venous plexus
– Connects orbit with infratemporal
fossa
– Connects orbit with temporal fossa
• Infra-orbital foramen
– Infra-orbital groove on the floor
connects to infra-orbital canal
anteriorly, and opens on the face at
infra-orbital f.
– Passed by infra-orbital n. (br. of CN V2)
Other openings on medial wall
• Anterior and posterior ethmoidal foramina
– passed by ant. and post. ethmoidal nn. and vessels, to ethmoid
bone
• Nasoacrimal canal
– passed by nasolacrimal duct, leads to inferior nasal meatus
Lacrimal gland
Ethmoidal
foramina
Optic canal
Nasolacrimal
duct
Periorbita
• Periosteum lining the orbit;
extends as orbital septa
• Thickening in posterior end
around optic canal as
common tendinous ring
(origin of four rectus mm.)
Fascial sheath of the eyeball
• Enclose eyeball, attaches to:
– sclera at the point of optic nerve entering eyeball,
– sclera near the edge of cornea,
– fascial sheath of muscles
• The lower part of fascial sheath is suspensory ligament.
Check ligaments of the
medial and lateral rectus muscles
• Thickening of investing sheath
covering med. and lat. recti
• Medial check ligament attaches
to the point immediately posterior
to posterior lacrimal crest.
• Lateral check ligament attaches
to the orbital tubercle of zygomatic
bone.
Extrinsic muscles
Extra-ocular mm. for moving eyeball or raising upper eyelid
• Elevation – moving pupil superiorly
• Depression – moving pupil inferiorly
• Abduction – moving pupil laterally
• Adduction – moving pupil medially
• Internal rotation – rotating upper part of pupil medially
• External rotation – rotating upper part of pupil laterally
Levator palpebrae superioris
• Function: raises upper
eyelid; innervation: CN III
Superior tarsal muscle
(smooth muscle) by
sympathetic ff.
• Origin: inferior surface of
levator palpebrae
superioris
• Function: assists to
maintain upper eyelid
elevation
Rectus muscles
• Superior and inferior rectus muscles
Function:
Sup. rectus – elevates, adducts, and internal rotates
Inf. rectus – depresses, adducts, and external rotates
Innervation: Sup. rectus – sup. br. of CN III
Inf. rectus – inf. br. of CN III
• Medial and lateral rectus muscles
Function:
Med. rectus – adducts
Lat. rectus – abducts
Innervation: Med. rectus – inf. br. of CN III
Lat. rectus – CN VI
Oblique muscles
• Superior oblique
Origin: body of sphenoid bone
–It runs along medial border of roof of orbit, passes through
fibrocartilaginous pully (trochlea).
–The muscle runs deep to superior rectus muscle
Inserts to outer posterior quadrant of eyeball
Function: turn pupil down and out
Innervation: CN IV
Oblique muscles
• Inferior oblique
Origin: medial side of floor of orbit, posterior to orbital rim
Insertion: outer posterior quadrant of eyeball
Function: turn pupil up and out
Innervation: inferior br. of CN III
SR
IO
IR
SO
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Internal carotid a. – gives off ophthalmic a. –
through optic canal – into orbit – gives off:
Lacrimal a. – lateral side of obit, to supply lacrimal gland, anterior ciliary br.
to eyeball, lateral eyelid
Central retinal a. – enters the center of optic n. to retina; its branches can
be seen with a ophthalmoscope; occlusion leads to blindness
Long and short posterior ciliary aa. –
pierce sclera to supply inside of eyeball
Muscular aa. – supply extrinsic mm.
Supra-orbital a. – passes through
supra-orbital f., to supply forehead and
scalp to vertex
Arteries
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Posterior ethmoidal a. – through posterior ethmoidal f. to supply
ethmoidal air cells and nasal cavity
Anterior ethmoidal a. – through anterior ethmoidal f.; gives off
anterior meningeal br.; enters nasal cavity to supply septum and lateral
wall; ends as dorsal nasal a. (ext. nasal a.)
Medial palpebral aa. – supply medial area of upper and lower eyelids
Dorsal nasal a. – supply upper surface of nose
Supratrochlear a. – supplies forehead
Veins
1. Supra-orbital v. and angular v. > Superior ophthalmic v.
> through superior orbital fissure > Cavernous sinus
2. Inferior ophthalmic v. >
 joining with superior ophthalmic v.
 through superior orbital fissure > Cavernous sinus
(infection can be spread from outside to cranial cavity)
 through inferior orbital fissure >
Pterygoid plexus of veins
1


Innervation
1. Optic nerve [II]
2. Oculomotor nerve [III]
3. Trochlear nerve [IV]
4. Abducent nerve [VI]
5. Postganglionic
sympathetic fibers
6. Ophthalmic nerve [V1]
6-1. Lacrimal nerve
6-2. Frontal nerve
6-3. Nasociliary nerve
7. Ciliary ganglion
7-1. Parasympathetic root
7-2. Sensory root
7-3. Sympathetic root
Optic nerve [II]
• Extension of brain; surrounded by meninges and
subarachnoid space
• High intracranial pressure increases the pressure in
subarachnoid space, and causes edema of optic disc
(papilledema).
• Through optic canal with ophthalmic a.
Oculomotor nerve [III]
• Anterior surface of brainstem, between midbrain and pons >
in the lateral wall of cavernous sinus > divides into sup. and
inf. brr. > enter orbit through superior orbital fissure >
Oculomotor nerve [III]
• Sup. br. >
1. superior rectus m.
2. levator palpebrae superioris m.
• Inf. br. >
1. medial rectus
2. inferior rectus
3. inferior oblique
4. br. to ciliary ganglion
(with pregang. parasym. ff.)
Trochlear nerve [IV]
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From posterior surface of midbrain >
enters the edge of tentorium cerebelli >
in the lateral wall of cavernous sinus (below CN III) >
through sup. orbital fissure (above common tendinous ring) >
upper border of superior oblique
Abducent nerve [VI]
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Anterior surface of brain stem between pons and medulla >
through cavernous sinus (lateral to int. carotid a.) >
through superior orbital fissure >
through common tendinous ring >
lateral rectus m.
Moore, 7th ed., Fig. I-45, p.60
Sympathetic fibers
• T1 (upper thoracic segments) > Preganglionic ff. >
• Spinal nn. > White rami > thru T1 sym. gang. > Sym. trunk >
• Superior cervical ganglion (synapse) >
Sympathetic fibers
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Superior cervical ganglion (synapse) >
Postganglionic ff. >
along internal carotid a. and brr. >
Ophthalmic a. > Orbit >
Pass through ciliary ganglion (without synapse) >
– Short ciliary nn. > Eyeball > Dilator pupillae m.
– Long ciliary nn. > Eyeball > Dilator pupillae m.
Ophthalmic nerve [V1]
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Pure sensory n. from orbit, face, scalp
Trigeminal ganglion >
in the lateral wall of cavernous sinus
(inferior to CN IV & III) >
divides into 3 brr.:
1. Lacrimal n. >
above common tendinous ring >
through superior orbital fissure
2. Frontal n. >
above common tendinous ring >
through superior orbital fissure
3. Nasociliary n. >
through common tendinous ring >
through superior orbital fissure
Lacrimal n.
• Along upper border of lat. rectus >
• receives a br. from zygomaticotemporal n.
(carries postgang. parasym. & sym. ff.) >
– Lacrimal gland (by CN VII)
– Conjunctiva
– Lateral upper eyelid
Frontal n.
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Between levator palpebrae superioris and periorbita >
divides into 2 brr.:
1. Supratrochlear n. > above trochlea >
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Conjunctiva
Skin on upper eyelid
Lower medial forehead
2. Supra-orbital n. >
through supra-orbital notch >
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Upper eyelid
Conjunctiva
Forehead to midscalp
Nasociliary n.
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Deep in orbit > between sup. and inf. brr. of CN III >
gives off communicating br. with ciliary gang. (sensory root) >
medial wall of orbit > gives off brr.:
1. Long ciliary nn. >
eyeball (with sensory and sym. ff.)
2. Posterior ethmoidal n. >
through posterior ethmoidal foramen >
• posterior ethmoidal air cells
• sphenoid sinus
3. Infratrochlear n. >
• medial part of upper and lower eyelids
• lacrimal sac
• skin of the upper nose
4. Anterior ethmoidal n. >
through anterior ethmoidal foramen >
• anterior cranial fossa
• nasal cavity
• skin of the lower nose
Ciliary ganglion
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Parasympathetic ganglion of CN III;
associated with nasociliary n. of CN V1;
located at the lateral side of optic n.
Synapse for pre- and postgang. parasym. ff.;
traversed by postgang. sym. ff.
It receives three roots: 2
1. Parasympathetic root
2. Sensory root
3. Sympathetic root
3
1
Parasympathetic root
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CN III > gives off parasym. root (carries pregang. parasym. ff.) >
synapse in ciliary ganglion > gives off postgang. parasym. ff. >
short ciliary nn. > eyeball >
Sphincter pupillae m. (constrict pupil)
Ciliary m. (accommodation of lens)
Sensory root
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Trigeminal gang. > CN V1 > Nasociliary n. >
sensory root pass through ganglion > short ciliary nn. >
Sensory innervation of eyeball
Sympathetic root
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Superior cervical ganglion >
gives off postgang. sym. ff. >
along plexus on int. carotid a. >
though common tendinous ring >
gives off a br. to join ophthalmic n. >
from nasociliary n. gives off a sym. root >
traverse ciliary gang. >
short ciliary nn. > eyeball >
Dilator pupillae m.
Eyeball
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1.
2.
3.
4.
5.
6.
Globe-shaped, bulges anteriorly as transparent cornea (1/6
surface area)
Light passes from ant. to post.:
Cornea >
Anterior chamber >
Iris, pupil >
Posterior chamber, lens >
Vitreous chamber >
Retina
Anterior and posterior chambers
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Anterior chamber – between cornea and iris
Pupil – central opening of iris
Posterior chamber – between iris and lens
Aqueous humor fills the posterior chambers, and flows through pupil
into anterior chamber, and is absorbed into scleral venous sinus.
• Glaucoma – amount of intraocular fluid increases, and consequently the
intra-ocular pressure.
Lens and vitreous humor
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Biconvex transparent disc
cataract is caused by the opacity of lens
Vitreous body (vitreous humor) – gelatinous substance in posterior
segment (postrenal chamber)
Walls of the eyeball
1. Outer fibrous layer: cornea and sclera
2. Middle vascular layer: choroid, ciliary body and iris
3. Inner layer: retina, and internal covering of iris and ciliary body
Arterial supply
1. Short posterior ciliary aa.
from ophthalmic a to pierce sclera
and enter choroid layer
2. Long posterior ciliary aa.
lateral and medial to optic n.,
run in choroids and
anastomose with anterior ciliary aa.
3. Anterior ciliary aa.
from muscular brr.;
anastomose with
long posterior ciliary aa.
in choroid layer
4. Central retinal a.
traverse the optic n. and
enters eyeball at optic disc
Venous drainage
•Four large veins (vorticose veins) enter
superior and inferior ophthalmic vv.
•Central retinal v. runs with a.
1. Fibrous layer of the eyeball
1-1. Sclera
Dense connective tissue; pierced by optic n. and attached by mm.;
covering lateral and posterior of 5/6 eyeball surface
Fascial sheath – covering outer surface of sclera from entrance of
optic n. to corneoscleral junction
Inner surface of sclera loosely attaches to choroid vascular layer.
1-2. Cornea
Transparent; anterior 1/6 of eyeball surface
2. Vascular layer of the eyeball
2-1. Choroid
Thin, highly vascular pigmented layer
firmly attaches to retina
loosely attaches to sclera
2-2. Ciliary body
between choroid and iris
Ciliary m. – smooth muscle ff., arranged longitudinally, circularly, and
radially; innervated by CN III
Contraction of the ciliary m. shrinks the ciliary body ring.
Ciliary processes – projections toward lens
Zonular fibers – extending from ciliary processes, attach to lens.
Collectively form suspensory ligament of lens
2-3. Iris
Circular structure with central opening, pupil; smooth mm. including:
Sphincter pupillae m. – innervated by parasym. ff., constricts the pupil
Dilator pupillae m. – innervated by sym. ff., dilates the pupil
3. Inner layer of the eyeball
• Retina –
3-1. Nonvisual part – covers internal surface of ciliary body and iris
Junction – irregular ora serrata
3-2. Optic part – sensitive to light
3-2-1. Pigmented layer – outer layer, attaches to choroids
3-2-2. Neural layer – attaches to pigmented layer around optic n. and at
ora serrata
Optic disc –
optic n. leaves the eyeball there;
the central a. enters eyeball there;
without light receptor there (blind spot)
Macula lutea –
with central depression, fovea centralis, thinner retina, and higher sensitivity
with more cones (sensitive to color) and fewer rods (functioning in dim light)