craniometric points

1. Craniometric Points of the Skull and Brain
Surface Landmarks
By Dr. Kedir.D (NSR)
Moderator: Dr. Eyob(Neurosurgeon)
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2. Outline
• Introduction
• Surface anatomy of the cranium
• Relation of skull markings to cerebral anatomy
• Cerebral key points
• Relationship of ventricles to skull
• Ventricular access points
• References
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3. INTRODUCTION
• The brain sulci and gyri constitutes the main
cortical and neuroanatomic limits, landmarks
and operative corridors.
• The identification of these anatomical
structures before and after performing the
craniotomy/craniectomy=>clinical
neuronavigation
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4. • The functional reliability of utilizing anatomical sulcal
and gyral landmarks are subjected to errors and cannot
safely replace the knowledge given by transoperatory
functional or neurophysiological testing.
• This is because of common anatomical functional
variations, their possible displacements and/or
involvement by the underlying pathology (Ebeling and
Reulen, 1992b; Ojemann et al., 1989; Simos et al., 1999;
Uematsu et al., 1992), or the plasticity more common in
long standing lesions (Duffau, 2011b).
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5. Surface Anatomy=>

6. Surface anatomy of the cranium: Craniometric points & cranial sutures
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7. Relation of skull markings to main
cerebral sulci and gyri
• Primary motor cortex area
• Central sulcus (CS): three methods
• Sylivian fissure
• Angular gyrus
• Chater’s point
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8. Central sulcus on imaging
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9. Craniometric Points for the Identification of Vascular Structure
• SSS
• Arachnoid granulations
• Bridging cortical veins
• Lacunae
• vein of Trolard
• vein of Labbé
• Transverse vs sigmoid sinus
Arachnoid granulations are commonly located
2.6 cm lateral to the SSS and can be found from 3.9 cm anterior to 7.3 cm posterior
to the Br.
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10. Craniometric Points for the Strategic Burr Hole Position
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11. Cerebral key points
• FRONTOTEMPORAL KEY POINTS
• THE SUPERIOR FRONTAL AND CENTRAL GYRUS
KEY POINTS
• PARIETAL KEY POINTS
• POSTERIOR AND OCCIPITAL POINTS
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12. FRONTOTEMPORAL KEY POINTS
1. The Anterior Sylvian Point (ASP)
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13. 2. The Inferior Rolandic Point (IRP)
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14. 3. The Inferior Frontal Sulcus and Precentral Sulcus Meeting
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15. THE SUPERIOR FRONTAL AND CENTRAL GYRUS KEY POINTS
1. The superior frontal sulcus and precentral
sulcus meeting point (SFS/PCS)
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16. 2. The superior Rolandic point (SRP)
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17. PARIETAL KEY POINTS
1. The intraparietal and post central sulcus
meeting point (IPS/PCS)
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18. 2. Craniometrical Key Point of The External Occipital Fissure (EOF)
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19. 3. The Euryon (Eu)
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20. POSTERIOR AND OCCIPITAL POINTS
1. Posterior temporal key point.
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21. 2. Occipital key point.
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22. Relationship of ventricles to skull
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23. Ventricular access points
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Kocher’s point

24. Paine’s, Hyun’s, and Park’s points
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25. Kaufman’s point
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26. Menovsky’s point
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27. Tubbs’ point
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28. Keen’s point
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29. Dandy’s point
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30. Frazier’s point
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31. Sanchez’s point
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32. References
• Greenberg 9th ed.
• Operative cranial neurosurgical anatomy
• www.neurosurgical approches.com
• Immersive Surgical Anatomy of the
Craniometric Points
• Craniometrics and Ventricular Access, 2020
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33. • The brain sulci can be used as microsurgical
corridors for the removal of cortical and
subcortical lesions, to reach the ventricular
cavities, or to serve as landmarks and limiting
surgical boundaries for subpial or transgyral
approaches.
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34. • Once the cortex is thicker over the crest of a convolution and thinner in
the depth of a sulcus (Carpenter and Sutin, 1983), theoretically, while
the actual transgyral approaches sacrifice a larger number of neurons
and of projection fibers, the transsulcal approaches sacrifice a larger
number of U fibers (Carpenter and Sutin, 1983; Harkey et al., 1989).
• The subpial approaches can be started either through a transcortical
opening just next to a sulcus or be initiated through a more limited
sulcal opening.
• The major disadvantage of the transsulcal approach is that the surgeon
has to deal with intrasulcal vessels with diameters proportional to the
dimensions of the sulci, and with occasional cortical veins that can run
along the sulci surface
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35. • On the other hand, it is meaningful to bear in mind that
studies on functional neuroimaging and intraoperative
cortical stimulation denote findings that, in general,
corroborate the expected relationships between elicited
functional responses and their respective eloquent
anatomical sites (Berger et al., 1990; Boling et al., 1999;
Brannen et al., 2001; Ebeling et al., 1992a; Ebeling and
Reulen, 1992b; Fitzgerald et al., 1997; Lobel et al., 2001;
Ojemann et al., 1989; Quiñones-Hinojosa et al., 2003; Rutten
et al., 2002; Schiffbauer et al., 2002; Simos et al., 1999;
Uematsu et al., 1992; Yousry et al., 1995).
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