98 |
6 Craniofacial Fracture Symptoms |
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Fig. 6.26 Perforation injury of the right orbital globe (ophthalmorrhexis) after tangential trauma to the lateral midface
Fig. 6.27 MRI of posttraumatic optic neuropathy (PTON). (a) Coronal T2-weighted image with swelling and elevated T2-signal in the right optic nerve. The low signal spot in the center of the nerve represents the optic artery (arrow). (b) Transverse T1-weighted
Frequency of isolated and combined orbital wall fractures in midfacial trauma (Kramp et al. 1997)
Isolated orbital wall-fractures |
4–16% of all facial fractures |
Combined midface/orbital |
30–55% of all facial fractures |
wall fractures |
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According to Kramp et al. (1997) the orbital floor is involved in 69% of all orbital fractures, the medial orbital wall in 19% and combined orbital floor and medial wall fractures in 10%.
Less common are orbital roof fractures at 1.2% and combined medial orbital wall/orbital floor/orbital roof fractures with a frequency of 0.6%.
Orbital wall involvement in midfacial fractures (Kramp et al. 1997)
Orbital floor |
69% |
Medial orbital wall |
19% |
Medial orbital wall + orbital floor |
10% |
Orbital roof fractures |
1.2% |
Medial orbital wall + orbital roof + orbital floor |
0.8% |
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image after i.v. contrast medium injection. Normal low signal of the left optic nerve. High signal of the right optic nerve representing intense contrast enhancement (arrow). The enhancement indicates posttraumatic inflammation of the nerve
6.3.3 Fracture Localization
6.3.3.1 Orbital Floor Fractures
In midface trauma, orbital floor fractures may be isolated or combined with additional midface fractures. On average, 72% of the orbital floor fractures show varying degrees of fragmentation, whereas 28% show only fissures without dislocation. The medio-nasal and central floor segments are usually affected (Hawes and Dortzbach 1983; Kramp et al. 1997).
Distribution of orbital floor fractures with simultaneous midfacial fractures (Kramp et al. 1997)
Entire orbital floor |
62% |
Segments of the orbital floor |
38% |
Medial orbital floor |
51% |
Central orbital floor |
42% |
Lateral orbital floor |
7% |
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6.3 Orbital Injuries |
99 |
|
|
Ophthalmological symptoms are found in 40% of |
injury to the orbital muscles with consequent distur- |
orbital floor fractures (Dutton and Al-Qurainy 1991). |
bances of eye motility or altered position of the globe |
Depending on fracture mode, there may be muscle or |
(Flanagan et al. 1980; Koornneff 1982, 1987; Joss |
ligament entrapment in the fracture gap as well as |
1995) (Figs. 6.28–6.34). |
Fig. 6.28 (a) The inner ligament and suspensory system in the periorbital fat of the eye. (b) Comminuted blow-out fracture of the orbital floor, resulting in herniation of periorbital fat into the maxillary sinus with consecutive enophthalmus. Dysbalance of the globe, incarceration of the radial periorbital ligaments and indirect restriction of the movement of the inferior rectus muscle (mod. a. Rowe and Williams 1985; Manson et al. 1986)
Fig. 6.29 Blow-out fracture of the orbital floor. Door- wing-like displacement of the medial half of the orbital floor into the maxillary sinus. Herniation of orbital fat into the sinus
Fig. 6.30 Blow-out fracture of the orbital floor. (a) Coronal CT image shows door-wing-like displacement of the medial half of the orbital floor into the maxillary sinus. Herniation of fat into the sinus (arrow). (b) The transverse image demonstrates the bone fragment within the sinus (arrow)
100 |
6 Craniofacial Fracture Symptoms |
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Fig. 6.31 Displaced right orbital floor fracture with herniation of bone and fat into the maxillary sinus. Bow-like downward displacement of the inferior rectus muscle (arrow)
Fig. 6.32 Blow-out fracture of the orbital floor with disruption of the inferior rectus muscle (arrow)
Fig. 6.33 Blow-out fracture of the orbital floor with massive herniation of orbital fatty tissue into the maxillary sinus (arrow) and with disruption of the inferior rectus muscle. Upper row: situation after the trauma. Lower row: scar formation (arrow) 3 months later
6.3 Orbital Injuries |
101 |
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Fig. 6.34 Combined left zygoma and orbital floor fracture. (a) Clinical view: enophthalmus, disturbance of eye motility, limitation of down gaze with diplopia. (b) CT: downward displacement of orbital floor and orbital soft tissue including rectus inferior muscle (arrow) into the maxillary sinus
Fig. 6.35 CT images of blow-out fracture of the right medial orbital wall with displacement of the bone fragment together with fatty orbital tissue into the ethmoid (arrow)
6.3.3.2 Medial Orbital Wall Fractures
Dislocation of the paper-thin lamina papyracea ossis ethmoidalis results in a medial fatty tissue prolapse into the ethmoid cells and orbital enlargement, leading to an enophthalmus. Medial orbital wall fractures often result in disturbed horizontal eye motility (abduction) and a retraction syndrome (Figs. 6.35–6.37).
6.3.3.3 Orbital Facial Fractures, Types:
Blow or Roof Fractures
Orbital roof fractures occur in approximately 5% of craniofacial fractures and may result in restricted eye motility, depressed position of the globe, ptosis (N.III) and neurological deficits (Klug and Machtens 1977; Ernst et al. 2004).
Characteristics of medial orbital wall fractures (blow-out fracture)
•Restricted horizontal movement
•Restricted abduction
•Globe retraction
•Subcutaneous emphysema
•Nasal hemorrhage
•X-ray: bone displacement/shading of the ethmoidal sinuses (20-70% in combination with orbital-floor fractures)
Clinical characteristics of orbital roof fractures
•Restricted elevation (rectus superior muscle)
•Ptosis (N. III)
•Depression of the globe (blow-in fractures)
•Neurological deficits (N.III)
•5% of facial-fracture types: blow-out/blow-in
In the case of orbital roof impression, one can occasionally palpate flattening in the area of the
102 |
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6 Craniofacial Fracture Symptoms |
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a1 |
a2 |
a3 |
b |
c |
Fig. 6.36 Displaced fracture of the medial orbital wall with diplopia. (a) Transverse and coronal CT images, demonstrating displacement of the left medial orbital wall into the posterior ethmoidal cells together with a substantial amount of orbital fat.
(b) Transnasal endoscopic view: demonstration of fat tissue prolapses into the ethmoid (arrow). (c) Hess-Weiss test: restricted abduction with diplopia.
supra-orbital region. Extensive injuries with dural tears may lead to liquor penetration into the upper-lid, resulting in a palpable cushioned swelling or pulsation of the periorbital region.
Ptosis of the upper lid caused by direct or indirect damage to the levator palpebrae muscle may be present. Diplopia is often a result of hemorrhage or entrapment of the rectus superior muscle or direct damage to the supplying nerve (N.III). Hypesthesia of the fore-
head region occurs as a result of injury to the supraorbital nerve.
Surgical revision is indicated if the globe is displaced, if roof fragments are displaced cranially, and especially if there is additional rhinoliquorrhea and neuromuscular disturbance. Bone fragments of the orbital roof have to be reduced or removed carefully. Larger orbital roof defects should be closed with autogenous grafts or resorbable membranes (Figs. 6.38 and 6.39).