ROLE OF MULTIDETECTOR SPIRAL-CT IN THE MANAGEMENT OF MAXILLO-FACIAL TRAUMATIC LESIONS

1. Department of Neuroradiology. Speciality Hospital. Rabat. Morocco ROLE OF MULTIDETECTOR SPIRAL-CT IN THE MANAGEMENT OF MAXILLO-FACIAL TRAUMATIC LESIONS S.BELABBES, M.FIKRI, M.R.EL HASSANI, M. JIDDANE HN9

2. INTRODUCTION • The facial traumatisms are a common reason for recourse to the care in emergency • Young adults+++ • circumstances of occurrence: roads accidents+++, agressions+++, falls, sports accidents, work accidents. • Multiple functional and aesthetic impacts, rarely vital( if associated with brain and cervical lesions). • spiral CT has an important place in the exploration of facial trauma

3. INTRODUCTION • The objectives of imaging: • Identification of fractures, irradiation and their potential displacement • Lesional type classification • Research of lesions potentially serious, requiring rapid intervention • Research of associated extra-facial lesions (cervical spine, brain ...)

4. MATERIALS and METHODS • retrospective study of 45 cases of maxillofacial traumatisms seen in emergencies and sent to the Department of Neuroradiology for evaluating • All our patients underwent CT in helical acquisition with multiplanar reconstruction and 3D

5. Results • The age of our patients was between 16 and 60 years. • Sex-ratio: 4m/1w • different CT aspects were found: Fractures of the orbit (floor, roof and lamina papyracea), fracture of the zygomatic process, sinus fracture, mandibular fracture (body, ramus and mandibular condyle), naso-ethmoido-maxilo-fronto-orbital complex fracture and Le fort fractures

6. DISCUSSION Pathophysiology-biomechanics Buttress anatomy: line diagram showing important facial buttresses. Vertical Buttresses Nasomaxillary Zigomaticomaxillary Pterygomaxillary Vertical mandible Central box: Nasal cavity+ethmoid Side boxes: maxillarysinuses + orbits Horizontal Buttresses A. Frontal Bar B. Inferior orbital rim C. Hard palate • Major resistance in the vertical axis • Low resistance to horizontal constraints (antero-posterior and lateral) • Fractures perpendicular to the pillars

7. DISCUSSION CT semiology • Indirect signs: • Swelling, soft tissue deformation • Fluidin a paranasal sinus, • Subcutaneousemphysema, pneumoencéphalie, • pneumo-orbit • Direct signs: • nonanatomic linear lucencies • cortical defect or diastatic suture • bone fragments overlapping causing a "double-density" • asymmetry of face

8. CT Indirect signes • Fluidin a paranasal sinus( ) • Subcutaneousemphysema( ) • Pneumoencéphalie( ) • pneumo-orbi ( ) • Given these signs, facial fracture is strongly suspected • Make reconstructions • with filter "hard" focused on the facial • Helping if necessary by 3D reconstructions

9. DISCUSSION Classification • Isolated fractures: • Fracture of the nose • Fracture of the zygomatic arch • zygomaticomaxillaryfracture • Fracture of the mandible • Fracture of the frontal sinus • complex fractures • Transverse fractures of the face (Le fort I, II, III) • Centro-facial fractures

10. Simple Fractures Fractures of nasal bone and nasal pyramid • The most common traumatic damage of the facial bone • Easydiagnosisclinically • X ray is usually sufficient( lateral view) • Emergency: In case of nasal septum hematoma Fracture of nasal bone fracture of the nasal septum ( ) (risk of hematoma)

11. Simple Fractures Zygomatic arch fracture • Can be identified in Hirtz ‘s incidence • Risk of blockage of the temporomandibularjoint by: • hematoma of the temporal muscle • fracture of the coronoid process of the mandible

12. Simple Fractures Zygomaticomaxillary fracture (Zygomatictripod fracture) • Latero-facial fracture is the most common • Detaches the zygomatic bone of the maxilla, orbit and temporal bone • Combines: • 1. zygomatico-frontal disjunction • 2. temporo-zygomatic disjunction • 3. zygomatico-maxillary fracture • 4. fracture of the zygomatic arch • 5. fractures of the anterior and posterolateralmaxillary sinus wall • Posterior extension: floor and side walls of the orbit, apex orbital and sphenoid body • Complications: • Orbital (hematoma, incarceration or muscle plug) • Nerve (infraorbitalduct injury) • Masticatory ( temporalis muscle plug)

13. Simple Fractures Zygomaticomaxillary fracture (Zygomatictripod fracture) Right zygomatic tripod fracture with the involvement of the nasolacrimal duct( ) and lateral orbital wall causing lateral rectus plug( )

14. Simple Fractures Zygomaticomaxillary fracture (Zygomatictripod fracture) Left zygomatic tripod fracture with involvement of the infraorbitalcanal( ) Fracture of orbital floor with inferior rectus plug by a bone splinter( )

15. Simple Fractures Fracture of the mandible • Fracture of the toothed portion and processes condylar • reaching the mental foramen • Fracture of the toothed maxillary or mandibular portion: open fracture • IT should always a seek joint damage (TMJ) associated sub-condylar Fracture (extra articular) Condylarfracture (intra articular) Risk of ankylosis

16. Simple Fractures Fracture of the mandible Distribution of mandibular fractures in order of frequency

17. Simple Fractures Fracture of the mandible Forces acting on the mandible and the relationship between muscle pulls and fracture angulation. A: Horizontally unfavorable. B: Horizontally favorable. C: Vertically unfavorable. D: Vertically favorable.

18. Simple Fractures Fracture of the mandible Transverse fracture of the alveolar portion of the mandible

19. Simple Fractures Fracture of the mandible unfavorable Para-symphysealright fracture associated with left condylar fracture

20. Simple Fractures Fracture of the mandible Bilateral para-symphyseal fracture with depression of the intercalary fragment associated with a right condylar fracture

21. Simple Fractures Fracture of the frontal sinus Clinical classification • Anterior table • Displaced • Un-displaced • Posterior table • Displaced • Un-displaced • Anterior and posterior table • Displaced • Un-displaced • Nasofrontalduct • Involved • uninvolved

22. Simple Fractures Fracture of the frontal sinus SimplifiedClinical Classification • Fracture of anterior table • Fracture with disruption of posteriorwall • Fracture involvingfloor of the sinus

23. Simple Fractures Fracture of the frontal sinus transfixing fracture of the frontal sinus with involvment of orbital roof

24. Complex Fractures Transverse fractures of the face Lefort fracture The LeFortI (Low-level fracture): • runs between the maxillary floor and the orbital floor. • It may involve the medial and lateral walls of the maxillary sinuses and invariably involves the pterygoid processes of the sphenoid. • Clinically, the floating fragment will be the lower maxilla with the maxillary teeth.

25. Complex Fractures Transverse fractures of the face Lefort fracture The LeFort II(Pyramidal fracture): • fracture crosses the nasal bones on the ascending process of the maxilla and lacrimal bone and crosses the orbital rim. • highest incidence of infraorbital nerve hypesthesias. • extends posteriorly to the pterygoid plates at the base of the skull.

26. Complex Fractures Transverse fractures of the face Lefort fracture The LeFort III(Craniofacial dysjunction): • Fracture traverses • the frontal process of the maxilla, • the lacrimal bone, • the lamina papyracea, • and the orbital floor. • Often involves the posterior plate of the ethmoid. • Highest rate of cerebrospinal fluid (CSF) leaks

27. Complex Fractures Transverse fractures of the face Lefort I Right Lefort II Lefort III

28. Complex Fractures Centro-facial fractures fracture of naso-ethmoïdo-maxillo-fronto-orbital complex • The nasal bones • Nasal septum • The ethmoid (including the cribriform plate) • The naso-frontal channels • The frontal process of maxilla • Orbital walls • The frontal sinus • High risk of osteo-dural breach by fracture of the posterior wall of the frontal sinus, the cribriform plate and roof of the ethmoid • Possible association with other fractures including Lefort

29. Complex Fractures Centro-facial fractures fracture of naso-ethmoïdo-maxillo-fronto-orbital complex

30. CONCLUSION • One must bear in mind that facial traumatism is above all a head trauma and cervical spine • The CT is the key in the exploration of facial trauma • The radiological must make an exhaustive study of the lesions • Indicate severe lesions requiring supervision or an urgent care