1. CRANIAL BASE (Lat. - BASIS CRANII)
Prof. Peter Stanko, MD, PhD
Oral and Maxillofacial Surgeon
Dpt. of Stomatology & Maxillofacial Surgery
Comenius University, St Elisabeth Hospital

2. BASIS CRANII (CRANIAL BASE)
A/ BASIS CRANII EXTERNA (external cranial base, outer surface) = three AREAS: ▪ area anterior (syn. nasoorbitalis) ▪ area medialis ▪ area posterior (syn. vertebronuchalis) B/ BASIS CRANII INTERNA (internal cranial base, inner surface) = three CRANIAL FOSSAE: ● fossa cranii ant. ● fossa cranii med. ● fossa cranii post.

3. External cranial base – I. AREA ANTERIOR (synonym NASOORBITALIS)
-medially top of the nasal cavity (meatus nasi sup. dx. + sin.) -laterally roof of the orbits (l. dx. + l. sin.).

4. External cranial base

5. External cranial base – II. AREA MEDIALIS
-Area pharyngea (clivus) -foramina for. n. V. (for. rotundum, for. ovale) → n. maxillartis, n. mandibulartis -foramina for vessels (canalis caroticus, for. jugulare) -both Temporomandibular joints (abbr. TMJ, Lat. – Articulatio temporomandibularis)

6. External cranial base

7. External cranial base – III. AREA POSTERIOR (synonym VERTEBRONUCHALIS)
-Foramen occipitale magnum -Atlantooccipital joint (Lat. – Articulatio atlantooccipitalis)

8. External cranial base

9. External cranial base

10. Internal cranial base – I. FOSSA CRANII ANTERIOR
-Lamina cribrosa (horizontalis) ossis ethmoidalis -Crista galli (insertion of falx cerebri).

11. Internal cranial basis - FOSSAE CRANII

12. Os ethmoidale Crista gali Lamina cribrosa (horizontal)
Lamina perpendicularis
(vertical)
Labyrintus - Celullae ethmoidales
(ant., mediae, post.)

13. Internal cranial base – II. FOSSA CRANII MEDIA
-sella turcica (location for hypophysis) ………..roof of sinus sphenoidalis -os petrosum (pyramid) ……..ganglion trigeminale Gasseri (cavum trig. Meckeli) -foramina (for. rotundum, for. ovale) → n. maxillartis, n. mandibulartis

15. Os sphenoidale

16. Ganglion trigeminale Gasseri

17. Internal cranial base – III. FOSSA CRANII POSTERIOR
► Foramen occipitale magnum ► C N S (pons Varolli + medula oblongata + cerebellum).

18. For. occipitale magnum

19. Central Nervous System (C N S)

20. Practical value of the knowledge of cranial base anatomy
-trunc anaesthesia (n. maxillaris, n. mandibularis) -infiltration in facial palsy (n. VII) -traumatology (fractures, CNS injuries etc.).

21. Areas of weakness of cranial base (Lat. – loci minoris resistentiae)
Predilection of fracture lines, especially in sites of conection of the weak and strong bones. Thickness of the bones - comparison of the three cranial fossae (cr.f.): ● the anterior cr. f. is the most thin and exposed, ● the medial cr.f. is strong but exposed indirectly through the coronoid process, ●the posterior cr.f. is thick and rarely exposed.

22. Usual course of fracture lines in cranial base fractures