INTERNAL HORDEOLUM
, A. Palpebra Anatomy
The superior and inferior lids are modified skin folds that can cover and
protect the anterior part of the eyeball. Palpebra consists of five main networks.
From the superficial to the inside there is a layer of skin, a layer of skeletal muscle
(orbicularis oculi), areolar tissue, fibrous tissue (tarsus), and a layer of mucous
membrane (pelpebral conjunctiva).
1. Skin
The skin on the lids differs from skin on other parts of the body in that it is thin,
loose, and elastic, with few hair follicles, and no subcutaneous fat.
2. The orbicularis oculi muscle
The function of this muscle is to close the lids. Its muscle fibers surround the
palpebral fissure concentrically and extend slightly beyond the orbital rim. Some
of the fibers run down the cheeks and forehead. The portion of the muscle
contained within the lids is known as the pretarsal portion; The portion above
the orbital septum is the preseptal portion. The outer segment of the lids is called
the orbital portion. The orbicularis oculi is innervated by the facial nerve.
3. areolar tissue
Located beneath the orbicularis oculi muscle, connected to the subaponeurotic
layer of the scalp.
4. Tarsus
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, A. Palpebra Anatomy
The superior and inferior lids are modified skin folds that can cover and
protect the anterior part of the eyeball. Palpebra consists of five main networks.
From the superficial to the inside there is a layer of skin, a layer of skeletal muscle
(orbicularis oculi), areolar tissue, fibrous tissue (tarsus), and a layer of mucous
membrane (pelpebral conjunctiva).
1. Skin
The skin on the lids differs from skin on other parts of the body in that it is thin,
loose, and elastic, with few hair follicles, and no subcutaneous fat.
2. The orbicularis oculi muscle
The function of this muscle is to close the lids. Its muscle fibers surround the
palpebral fissure concentrically and extend slightly beyond the orbital rim. Some
of the fibers run down the cheeks and forehead. The portion of the muscle
contained within the lids is known as the pretarsal portion; The portion above
the orbital septum is the preseptal portion. The outer segment of the lids is called
the orbital portion. The orbicularis oculi is innervated by the facial nerve.
3. areolar tissue
Located beneath the orbicularis oculi muscle, connected to the subaponeurotic
layer of the scalp.
4. Tarsus
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