DƯỢC LÍ Goodman & Gilman's The Pharmacological Basis of Therapeutics 12th, 2010

1774
Superior oblique muscle
Levator palpebrae superioris muscle
Superior rectus muscle
Medial rectus muscle
Trochlea (pulley)
Optic nerve (II)
1
Lateral rectus
muscle (cut)
Lateral rectus
muscle (cut)
Inferior oblique
muscle
2
SECTION IX
SPECIAL SYSTEMS PHARMACOLOGY
Inferior rectus muscle
1. Subconjunctival route
2. Retrobulbar route
3. Peribulbar route
Figure 64–1. Anatomy of the globe in relationship to the orbit and eyelids. Various routes of administration of anesthesia are demonstrated
by the blue needle pathways.
enter the puncta and continue to drain through the
canaliculi, lacrimal sac, nasolacrimal duct, and then
into the nose. The nose is lined by a highly vascular
mucosal epithelium; consequently, topically applied
medications that pass through this nasolacrimal system
have direct access to the systemic circulation.
Ocular Structures
The eye is divided into anterior and posterior segments
(Figure 64–3A). Anterior segment structures include
the cornea, limbus, anterior and posterior chambers, trabecular
meshwork, canal of Schlemm (Schlemm’s
canal), iris, lens, zonule, and ciliary body. The posterior
segment includes the vitreous, retina, choroid,
sclera, and optic nerve.
Anterior Segment
Cornea. The cornea is a transparent and avascular tissue organized into
five layers: epithelium, Bowman’s membrane, stroma, Descemet’s
membrane, and endothelium (Figure 64–3B). Representing an
important barrier to foreign matter, including drugs, the hydrophobic
3
Superior lacrimal papilla and puncta
Lacrimal canaliculi
Orbital (superior)
part of lacrimal gland
Palpebral (inferior)
part of lacrimal gland
Lacrimal sac
Ducts of lacrimal gland
Nasolacrimal duct
Opening of
nasolacrimal duct
Inferior lacrimal papilla and puncta
Figure 64–2. Anatomy of the lacrimal system.