1. Imaging of disease spread through the skull base Eufrozina Selariu Skåne Universitetssjukhus Malmö Sweden

2. Characterisation of the lesion Morphology 1. tissue characterisation Morphology 1. tissue characterisation 2. pattern of bone involvment 2. pattern of bone involvment 3. vascularity 3. vascularity Localisation 1. intrinsic to the skull base Localisation 1. intrinsic to the skull base 2. arrising from intracranial compartment 2. arrising from intracranial compartment 3. arrising from extracranial head and neck 3. arrising from extracranial head and neck Invasion of other structures Invasion of other structures 1. Direct extension 1. Direct extension infiltrating bone, soft tissue, meninges, cerebrum infiltrating bone, soft tissue, meninges, cerebrum preformed channels and foramina preformed channels and foramina 2. Hematogenous spread 2. Hematogenous spread 3. Perineural spread 3. Perineural spread

3. Glomus Jugulare Paraganglioma

4. Dural arteriovenous fistula

5. Bone involvement pattern

6. Agressive bone involvement pattern Osteolysis Osteolysis Absent bone replaced by soft tissue Absent bone replaced by soft tissue Thinned bone with soft tissue mass on its both sides Thinned bone with soft tissue mass on its both sides Abnormal signal of the bone marrow Abnormal signal of the bone marrow Calcifications within the soft tissue mass Calcifications within the soft tissue mass

7. Non-aggressive bone involvement pattern Bone remodeling with bowing, thin or demineralized walls Bone remodeling with bowing, thin or demineralized walls Bone expansion with smooth contour or interrupted walls Bone expansion with smooth contour or interrupted walls Enlarged intramedullary cavity Enlarged intramedullary cavity Varying attenuation: ground-glass, radiolucent or sclerotic Varying attenuation: ground-glass, radiolucent or sclerotic

8. Eosinophilic granuloma Clivus Chordoma Eosinophilic granuloma Clivus Chordoma

9. Juvenil Angiofibroma

10. Pituitary adenoma

11. Direct extension by preformed pathways

12. Esthesioneuroblastoma Olfactorius meningioma

13. Trigeminal Neurofibroma

14. Sphenoid meningioma Optic nerve meningioma

15. Abscess MPS, PPS, MS, CS, RPS Pharygeal mucosal space PMS Sinus Morgagni Pharygeal mucosal space PMS Sinus Morgagni Parapharyngeal space PPS Skull base Parapharyngeal space PPS Skull base Carotid space CS Canalis caroticus Carotid space CS Canalis caroticus Jugular foramen Jugular foramen Mandibular space MS Foramen ovale Mandibular space MS Foramen ovale Retropharyngeal space RPS Basiocciput Retropharyngeal space RPS Basiocciput

16. Direct extension by infiltrating structures

17. Skull base Metastasis Skull base Metastasis Occur in bone with high marrow content Occur in bone with high marrow content Osteoblastic metastasis Osteoblastic metastasis Hypervascular metastasis Hypervascular metastasis Osteolytic metastasis Osteolytic metastasis

18. Frontal sinus Squamous Cell Carcinoma

19. Sinus frontalis Squamous Cell Cancer with intracranial spread Nodular dural enhancing have high specificity Nodular dural enhancing have high specificity Dural thickness > 5 mm Dural thickness > 5 mm Coexistent leptomeningeal enhancement Coexistent leptomeningeal enhancement Brain parenchymal changes Brain parenchymal changes

20. Hematogenous spread

21. Acute Mastoiditis – Local complications Subperiosteal abscess Subperiosteal abscess Sinus thrombosis Sinus thrombosis Bezold abscess Bezold abscess Perisinus and epidural abscess Perisinus and epidural abscess Petrositis Petrositis Labyrintitis Labyrintitis

22. Acute Otitis Intracranial complications Cavernous sinus thrombosis Enlarged superior ophtalmic veins Exophtalmus Inhomogenous enhancement of cavernous sinus

23. Acute Otitis - Intracranial complications Subdural empyema Meningitis Petrous apicitis

24. Perineural spread Nerve enlargement and nerve enhancement Nerve enlargement and nerve enhancement Obliteration of the fat in the foramina, fosse or fissures Obliteration of the fat in the foramina, fosse or fissures Foraminal enlargement or destruction Foraminal enlargement or destruction Enhancing soft tissue in the cavernous sinus and Meckel cave Enhancing soft tissue in the cavernous sinus and Meckel cave Neuropathic atrophy and fat replacement Neuropathic atrophy and fat replacement Tumor growth Tumor growth Incresed permeability of endoneurial capillaries Incresed permeability of endoneurial capillaries Rupture of the blood-nerve barrier Rupture of the blood-nerve barrier Contrast-enhancement Contrast-enhancement

25. Perineural spread Blood-nerve barrier disruption with segmental nerve enhancement Blood-nerve barrier disruption with segmental nerve enhancement Inflammation – neuritis Inflammation – neuritis Ischemia Ischemia Trauma Trauma Demyelination Demyelination Axonal degeneration Axonal degeneration Normal variant enhancement of Gasser ganglion and V2, V3 Normal variant enhancement of Gasser ganglion and V2, V3 Adenoid cystic carcinoma Adenoid cystic carcinoma Mucoepidermoid carcinoma Mucoepidermoid carcinoma Squamos cell carcinoma Squamos cell carcinoma Adenocarcinoma Adenocarcinoma

26. Ethmoidal Adenocarcinoma with perineural spread in pterigopalatine fossa

27. Role of imaging Diagnosis Diagnosis Extent of disease – criteria of surgical resectability Extent of disease – criteria of surgical resectability Treatment planning – surgical approach Treatment planning – surgical approach Follow-up – reccurence versus posttreatment changes Follow-up – reccurence versus posttreatment changes

28. Thank you !