Overview and topographic anatomy
General information
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Fascia— a band of connective tissue that surrounds structures (such as enveloping muscles), giving rise to potential tissue spaces and pathways that allow infection to spread
Superficial fascia
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Immediately deep to the skin
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Contains fat
Deep fascia
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Deep to the superficial fascia
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Aids muscle movements
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Provides passageways for nerves and vessels
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Provides attachment for some muscles
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In the neck, it is divided into 4 regions :
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Visceral region
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Musculoskeletal region
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2 neurovascular compartments
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Also divided into 4 layers :
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Superficial layer of deep cervical fascia (investing layer of deep cervical fascia)
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Middle layer of deep cervical fascia
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Deep layer of deep cervical fascia
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Carotid sheath (composed of the contributions of all 3 layers of deep cervical fascia)
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There is no deep fascia in the face, which allows free spread of fluid
Fascia of the neck
Superficial fascia
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Superficial fascia lies deep to the skin and contains the cutaneous vessels and nerves
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In the neck, the platysma muscle lies within the superficial fascia
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Has a variable amount of adipose tissue, depending on the individual patient
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Superficial fascia has fibrous septa, which can help localize infections
Deep fascia
| SUPERFICIAL LAYER OF DEEP CERVICAL FASCIA (sometimes referred to as the investing layer) | |||
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| MIDDLE LAYER OF DEEP CERVICAL FASCIA (sometimes collectively referred to as the pretracheal fascia) | |||
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| DEEP LAYER OF DEEP CERVICAL FASCIA (sometimes collectively referred to as the prevertebral fascia) | |||
| Layer | Location | Attachment | Comments |
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| COMBINATION OF ALL 3 LAYERS | |||
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| Layer | Location | Attachment | Comments |
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Fascial spaces
General information
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Layers of fascia create “potential” fascial spaces
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All are filled by loose areolar connective tissue
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Infections or other inflammatory conditions can most easily spread through fascial spaces because they provide a path of least resistance
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Most odontogenic infections are caused by endogenous bacteria
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Spread typically is between contiguous fascial layers, but bacteria release enzymes that cause cellular lysis, which can allow spread between fascial spaces that are not continuous
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The hyoid bone is the most important anatomic structure in the neck that limits the spread of infection
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Most are divided into spaces in relation to the hyoid bone:
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Suprahyoid
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Infrahyoid
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Entire length of the neck
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In dentistry, fascial spaces are classified according to mode of spread of odontogenic infections
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Thus fascial spaces are designated as either primary , with infection occurring by direct spread from involved tissue, or secondary , with infection occurring by spread from another space
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A commonly accepted classification is:
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Primary maxillary spaces:
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Canine
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Buccal (bridges between maxillary and mandibular regions)
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Infratemporal
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Primary mandibular spaces:
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Submandibular
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Submental
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Sublingual
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Buccal (bridges between maxillary and mandibular regions)
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Secondary spaces:
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Masticator (pterygomandibular, submasseteric, temporal)
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Lateral pharyngeal
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Retropharyngeal
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Parotid
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Prevertebral
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Some of the fascial spaces are directly continuous with other fascial spaces, whereas others will communicate if an infection breaks through a wall
