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30 Cards in this Set
- Front
- Back
Vertical Buttresses
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1. Naso-maxillary (NM)
2. Zygomatico-maxillary (ZM) 3. Pterygo-maxillary (PM) 4. Nasal septum |
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Horizontal Beams
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1. Frontal bar
2. Inferior orbital rims 3. maxillary alveolus and palate 4. zygomatic process 5. Greater wing of the sphenoid 6. Medial and lateral pterygoid plates 7. Mandible |
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3 vaults of nose
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Upper: nasal bones, ethmoid, superior edge of septum, vomer
Middle: upper lateral cartilage, septum, ascending process of maxilla Lower: lower lateral cartilages, inferior portion of septum |
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Nasal Fractures Classification (Stranc & Robertson)
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Plane 1: distal ends of nasal bones and septum only
Plane 2: involves entire distal portion of nasal bones and frontal process of maxilla at the piriform aperture. Septum is comminuted and begins to lose height Plane 3: Involvement of one or both frontal processes of maxilla at the piriform aperture. Fracture extends to frontal bone (NOE) |
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Normal intercanthal distance
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33mm (>35mm = abnormal)
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Medial canthal tendon composition
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anterior limb:
- superficial head of orbic - inserts onto frontal process of maxillary bone into anterior lacrimal crest posterior limb: - deep head of orbic - inserts onto posterior lacrimal crest |
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Markowitz NOE Classification
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Type 1:
- single central segment - no disruption medial canthal tendon (MCT) Type 2: - comminuted central segment - no disruption MCT Type 3: - severe comminuted central segment - disrupted/ avulsed MCT |
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How is the eyelid traction test (Bowstring sign) useful in NOEs?
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Grasp lower lid with forceps and pull laterally (opposite to MCT)
inability to pull lid taut = complete disruption of MCT |
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4 fractures in an NOE
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- frontal process of maxilla
- nasal bones - medial orbital wall - inferior orbital wall |
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Surgical approaches to NOE
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1: coronal
2: lower eyelid 3: gingival buccal sulcus incision 4: local incision (vertical, open sky, laceration) |
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How to repair medial canthal tendon in NOE fracture
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- Transnasal wiring (30 gauge wire)
- posterior/superior to lacrimal apparatus - tendon repaired with 2-0 nonabsorbable suture |
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What drains into middle meatus?
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maxillary sinus, frontal sinus, anterior cells of ethmoid sinus
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What drains into inferior meatus?
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Nasolacrimal canal
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What drains into superior meatus?
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posterior ethmoidal cells
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What is the Foramina of Breschet?
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- site of venous drainage of the frontal sinus mucosa
- potential route of intracranial spread of infection |
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What is the risk if mucosa of frontal sinus is not completely obliterated in cranialization?
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Mucocele formation
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What separates frontal sinus from brain?
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Cribiform plate
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Indications for surgery in frontal sinus fracture
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- anterior table displacement with contour change
- nasofrontal duct involvement - displaced posterior table |
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When do you obliterate frontal sinus?
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if nasofrontal duct involved
*NOE, medial/superior orbital, orbital floor fractures assumed to have nasofrontal duct involvement |
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When do you perform cranialization?
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if CSF leak and posterior table is displaced, or if it is non-displaced but leak is persistent > 4-7days
- involves removal of posterior table, obliteration of nasofrontal duct, reduction of anterior wall |
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Muscles that attach to zygoma
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- masseter
- temporalis - zygomaticus - zygomatic head of quadratus labii superioris |
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Fracture sites of Lefort 1
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AKA Guerin or transverse Fracture
1: Pterygoid plates 2: Pyriform aperture (inferior medial maxillary buttress) 3: alveolar maxilla (inferior lateral maxillary buttress) |
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Fracture sites of Lefort 2
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AKA Pyramidal fracture
1: pterygoid plates 2: nasofrontal junction 3: medial aspect of inferior orbital rim (transverse maxillary buttress) 4: lateral maxillary buttress |
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Fracture sites of Lefort 3
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1: pterygoid plates
2: nasofrontal junction 3: entire orbital floor 4: zygomaticofrontal suture (upper transverse maxillary buttress) 5: zygomaticosphenoid suture |
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Hendrickson palate fracture classification
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Type I Anterior and posterolateral alveolar
Type II Sagittal Type III Para-sagittal Type IV Para-alveolar Type V Complex Type VI Transverse |
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How common is CSF leak in Lefort 2 and 3?
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25-50%
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Most common facial fractures
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1. Mandible
2. zygoma 3. orbit |
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Percentage of facial fractures with C-spine injury
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7% (14% of c-spine injuries have facial fractures)
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Percentage of facial fractures with brain injury
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68%
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Percentage of ocular injury
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25%
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