Nasoorbitoethmoid (NOE) fracture: NOE fractures may

disrupt the medial canthal tendon and extend into the

lacrimal apparatus. Displacement or comminution of the bony

fragments posteriorly into the ethmoid or superiorly into the

anterior fossa should be identified.

Mandible fracture: Mandibular fractures can occur within or

posterior to the teeth. The mandible essentially functions as a

"ring of bone" and multiple, often bilateral, fractures are

common. The fractures should be located, the

degree/direction of fragment displacement identified, and

the condyles evaluated for subluxation or dislocation.

Involvement of the inferior alveolar canal and teeth should be

determined.

Approach to Spine and Cord Trauma

Imaging Acute Spine Injuries

Although radiographs are still used for evaluating the spine,

MDCT has become the procedure of choice in rapidly

assessing patients with possible spine injuries. In patients with

moderate to severe injuries, obtaining large datasets that are

subsequently parsed into C-, T-, and L-spine studies together

with chest, abdomen, and pelvis is increasingly common.

Thin-section axial images are easily reformatted into sagittal

and coronal views. Both bone algorithm and soft tissue

reconstructions are typically performed. CTA is a helpful

adjunct if vascular injury is a risk (BOS fractures that cross

carotid canal or dural venous sinus, cervical spine fractures

that traverse foramen transversarium, posterior element

subluxation, etc.). Emergent MR is especially helpful in

patients with suspected ligamentous complex damage,

traumatic disc herniation, or cord injury.

Spine Fracture Classification

Craniovertebral junction (CVJ): Initial evaluation in patients

with suspected CVJ injury should begin with a focus on

identification of craniocervical malalignment followed by

delineation of specific fractures. These are classified by level

and type of injury as well as potential for instability. Although

an exhaustive description is beyond the scope of this text, a

few selected fractures are briefly delineated here.

C1 fractures often involve the posterior arch. A Jefferson

fracture is a vertical compression fracture in which both the

anterior and posterior rings are disrupted and displaced

radially. A combined lateral mass displacement (relative to C2

lateral masses) of ~ 7 mm indicates disruption of the

transverse ligament and potential instability.

Odontoid fractures are classified anatomically into 3 types:

Type I = avulsed tip, type II = transverse dens fracture above

the C2 body, and type III fractures involve the superior portion

Trauma, and Stroke

Brain: Pathology-Based Diagnoses: Malformations,

33