Transcript Slide 1

Lymphatic System
• Lymphatic system: system of lymphatic
vessels and organs
• for the transport of lymph
• lymph: filtrate produced in tissues and
NOT reabsorbed by the capillaries of the
CV system
– produced through large-scale filtration of
plasma into tissues
– carried through a system of lymphatic
vessels and filtered through lymph nodes
Lymphatic organs:
1) lymph nodes: found at certain points along the lymphatic system
-capsule surrounding an outer cortex and inner medulla
-cortex contains immune cells = lymphocytes
-medulla contains immune cells = macrophages
-cleans lymph and fights specific pathogens
2) tonsils: lymphatic tissue located in the pharynx (adenoids) or oral cavity
(palatine tonsils)
-collection of lymphocytes and
macrophages
-”cleans” food and drink and air
-first defense against pathogens
3) Spleen - collection of lymphocytes and
macrophages
-cleans the blood
4) bone marrow – stem cells +
lymphocytes/macrophages
-cleans the blood
5) Thymus – production of T cells
Lymph nodes:
-1 to 2 cm bean shaped
-surrounded by a fibrous capsule which extend into the node to form trabeculae
-fed by afferent lymphatic vessels
-drained by efferent lymphatic vessels
-made up of tissue organized as an outer cortex and an inner medulla
-cortex contains numerous follicles – site of T and B cells
-outer cortex follicles = B cells
-deep cortex = site of T cells
-number and composition of the follicles can change according to the antigen being
recognized
-medulla made up of medullary cords of lymphatic tissue = contain B cells, plasma
B cells and macrophages
-between the cords are spaces called medullary sinuses = site of macrophages
lymph -> afferent vessel -> subcapsular sinus -> trabecular sinuses -> medullary sinuses ->
efferent vessel
-cervical nodes
-clavicular nodes
-axillary nodes
-mediastinal nodes
-mesenteric nodes
-inguinal nodes
Lymph nodes
• Nodes of the head and neck drain into two large
groups
– Superior deep cervical nodes (SDCs)
• Drain the external/middle ear, sinuses, nasal cavity, lacrimal
gland, scalp and face
• Also drains several oral structures: floor of mouth, base of
tongue, maxillary and mandibular teeth, tonsils, salivary
glands, palate
– Inferior deep cervical nodes (IDCs)
• Drains the cervical nodes (external & anterior jugular nodes)
• Also drains some of the axillary nodes and the deep posterior
triangle of the neck
• Refer to handouts
Superficial nodes of Head & Neck
• Nodes of the Head: drain to superior deep cervical nodes
– Figures 10-3, 10-4, 10-5
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Occipital – drain to inferior deep cervical nodes
Retroauricular
Anterior auricular
Superficial parotid
Facial nodes
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Malar
Nasolabial
Buccal
mandibular
• Nodes of the Cervical region: drain into superior or inferior
deep cervical nodes
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Retropharyngeal – drains into SDCs
Submental – drains into submandibular nodes
Submandibular – drains into SDCs
External jugular or Superficial lateral cervical nodes – drains into IDCs
Anterior jugular or Superficial anterior cervical nodes – drains into
IDCs
Cervical Nodes
-lymphatic vessels join to form two major ducts:
1) thoracic duct (joins to the left subclavian vein as the left lymphatic
duct)
2) right lymphatic duct – connects to right subclavian vein
-right arm & thorax, right side of head and neck -> right jugular trunk -> right
lymphatic duct -> right subclavian vein (at junction of internal jugular)
-left arm & thorax, lower body, left side of head and neck -> left jugular trunk ->
thoracic duct -> left subclavian vein (at junction of internal jugular)
lymphatic system is
ONE WAY
(from tissues to
heart)
Lymphatic vessels
-lymphatic vessels - for the transport of
lymph
-larger lymphatic vessels are similar to blood
vessels - presence of valves
-enters lymphatic capillaries from the tissues
-low pressure system - moves by
muscular contraction and breathing
-capillaries join to form lymphatic vessels
Tonsils
• not located along lymphatic
vessels
• drain into the superior deep
cervical lymph nodes
• reach their largest size during
puberty
• four types – known as Waldeyer’s
ring
– Palatine – located in oropharynx
• Behind the palatoglossal arch
– Lingual – base on tongue
– Pharyngeal or Adenoids
• located in nasopharynx
– Tubal
• located in nasopharynx
• Tonsillitis is an inflammation the tonsils in the mouth and
will often, but not necessarily, cause a sore throat and
fever. It may be caused by Group A streptococcal
bacteria and similar appearances may also be seen in
glandular fever. Most tonsilitis however is viral in origin.
• other tonsillar complications
– peritonsillar abcesses or quinsy can eventually lead to
septicaemia
– hypertrophy of tonsils can disturb sleep, lead to snoring and
mouth breath and even sleep apnea
– consumption of mucus by bacteria on tonsils – produce whitishyellow deposits called tonsilloliths or tonsil stones – produce a
sulforous odour.
Fascia
• Two types
1. Superficial
2. Deep
• Superficial fascia
– Connects skin to underlying structures
– Can contain copious amounts of fat
• Deep fascia – two divisions
– A. face & jaws
– B. deep cervical
Fascia
• Face & jaws: continuous with deep cervical fascia
– Temporal – covers temporalis muscle and runs down to the zygomatic
arch
– Masseteric-parotid – below the zygomatic arch
• Covers the masseter and parotid gland
– Pterygoid – found on the medial side of the medial pterygoid muscle
• Deep cervical: all continuous with each other and with the fascia of
the face and jaw
– Investing – most external layer
• Surrounds the musculature of the neck
• Completely encloses the submandibular and parotid glands (continuous with the
masseteric-parotid fascia), the sternocleidomastoid and the trapezius
– Carotid sheath – encloses the external carotid, the internal jugular and
the vagus nerve
– Visceral – encloses the thyroid gland, trachea, esophagus
• Near the skull this fascia is known as the buccopharyngeal fascia
– Vertebral – deepest layer
• encloses the deep musculature of the vertebral column and the vertebral column itself
(e.g. semispinalis, longissimus, spinalis)
Fascial spaces
• Spaces created by the deep fascia of face, jaws
and cervical regions
• All interconnected with each other
• With the exception of the parotid space
• Parotid space
– Contains the parotid gland and facial nerve branches, external
jugular branches and retromandibular vein
• http://flashcarddb.com/cardset/124977-fascial-spaceslect-5-mod-4-flashcards
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Contain specific anatomical structures
Retropharyngeal – danger space
Parapharyngeal – lymph nodes
Previsceral – nodes and cervical vessels
Space of the body of the mandible – mandible and inferior alveolar
nerve
Vestibular space of mandible
Submental space – submental nodes and anterior jugular
Buccal - fat
Pterygomandibular space of infratemporal region
Canine
Sublingual – sublingual gland and ducts, submandibular ducts,
lingual nerve and artery, cranial nerve XII
Submandibular – submandibular nodes and gland, facial artery
Masticator space – temporal space + submasseteric space +
infratemporal space
– Infratemporal space – maxillary artery, mandibular nerve, pteygoid
plexus
Vestibular space
-these spaces communicate directly with the eponymous teeth
e.g. vestibular space of the maxilla – maxillary molars and
periodontium
e.g. vestibular space of the mandible – mandibular teeth and
peridontium
-buccal space: between the buccinator and masseter muscles
-contains fat
-covered by part of the parotid fascia
-communicates with the canine and pterygomandibular spaces & space
of the body of the mandible
-canine space: anterior border is the orbicularis oris
-posterior border is the levator anguli superioris
-located above the upper lip and to the side of the maxillary canine
-sits below muscle that lift the upper lip: the levator labii superioris,
orbicularis oris, zygomaticus muscles
Temporal space
Infratemporal space
Submasseteric space
The Masticator Spaces
1. Temporal space
2. Infratemporal space
3. Submasseteric space
Masticator spaces
• General term for the area of the mandible & associated
muscles of mastication
– 1. temporal space (fig. 11-7): between the fascia that covers
the temporalis muscle and the actual muscle
– 2. infratemporal space (fig. 11-8): found in the infratemporal
fossa
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Medial border – lateral pterygoid m.
Lateral border – mandible and temporalis m.
Superior border/roof – greater wing of sphenoid
Anterior border – pharynx
Contains the pterygomandibular space (fig 11-8) – contains the
inferior alveolar nerve
• Contains part of maxillary artery, mandibular nerve & branches,
medial and lateral pterygoid muscles
– 3. submasseteric space (fig. 11-9): between the masseter &
ramus of mandible
Space of the body
of the mandible
-contains the inferior alveolar nerve (V3) and inferior
alveolar artery (maxillary artery)
in addition to the mandibular dental plexus, mental
and incisive branches of the IAN
-sublingual and submandibular
spaces contain the SL and SM glands
and lymph nodes
-the SL space also contains the ducts
for the SL and SM glands
-the SM space contains
part of the facial artery
-the SL space contains part of the lingual
nerve and artery + XII
Sublingual &
Submandibular spaces
Submental &
Submandibular spaces
-submental space: roof is the
mylohyoid m.
-floor is the superficial fascia that
covers the suprahyoid m.
-lateral border is the anterior belly of
digastric m.
Parotid space
Parapharyngeal space: lateral
To the pharynx
-media to the medial pterygoid m.
-adjacent to the carotid sheath
-Contains lymph nodes
-continues with retropharyngeal space
Retropharyngeal space: posterior to
pharynx
-located between the vertebral &
visceral fascia
-called the danger space: extends from base
of skull into the thorax
Parapharyngeal &
retropharyngeal spaces