- •Operative Cranial Neurosurgical Anatomy
- •Contents
- •Foreword
- •Preface
- •Contributors
- •1 Training Models in Neurosurgery
- •2 Assessment of Surgical Exposure
- •3 Anatomical Landmarks and Cranial Anthropometry
- •4 Presurgical Planning By Images
- •5 Patient Positioning
- •6 Fundamentals of Cranial Neurosurgery
- •7 Skin Incisions, Head and Neck Soft-Tissue Dissection
- •8 Techniques of Temporal Muscle Dissection
- •9 Intraoperative Imaging
- •10 Precaruncular Approach to the Medial Orbit and Central Skull Base
- •11 Supraorbital Approach
- •12 Trans-Ciliar Approach
- •13 Lateral Orbitotomy
- •14 Frontal and Bifrontal Approach
- •15 Frontotemporal and Pterional Approach
- •16 Mini-Pterional Approach
- •17 Combined Orbito-Zygomatic Approaches
- •18 Midline Interhemispheric Approach
- •19 Temporal Approach and Variants
- •20 Intradural Subtemporal Approach
- •21 Extradural Subtemporal Transzygomatic Approach
- •22 Occipital Approach
- •23 Supracerebellar Infratentorial Approach
- •24 Endoscopic Approach to Pineal Region
- •25 Midline Suboccipital Approach
- •26 Retrosigmoid Approach
- •27 Endoscopic Retrosigmoid Approach
- •29 Trans-Frontal-Sinus Subcranial Approach
- •30 Transbasal and Extended Subfrontal Bilateral Approach
- •32 Surgical Anatomy of the Petrous Bone
- •33 Anterior Petrosectomy
- •34 Presigmoid Retrolabyrinthine Approach
- •36 Nasal Surgical Anatomy
- •37 Microscopic Endonasal and Sublabial Approach
- •38 Endoscopic Endonasal Transphenoidal Approach
- •39 Expanded Endoscopic Endonasal Approach
- •41 Endoscopic Endonasal Odontoidectomy
- •42 Endoscopic Transoral Approach
- •43 Transmaxillary Approaches
- •44 Transmaxillary Transpterygoid Approach
- •45 Endoscopic Endonasal Transclival Approach with Transcondylar Extension
- •46 Endoscopic Endonasal Transmaxillary Approach to the Vidian Canal and Meckel’s Cave
- •48 High Flow Bypass (Common Carotid Artery – Middle Cerebral Artery)
- •50 Anthropometry for Ventricular Puncture
- •51 Ventricular-Peritoneal Shunt
- •52 Endoscopic Septostomy
- •Index
50 Anthropometry for Ventricular Puncture
Michele Bailo, Filippo Gagliardi, Alfo Spina, Cristian Gragnaniello, Anthony J. Caputy, and Pietro Mortini
50.1 Indications
•Acute hydrocephalus.
•Intracranial hypertension:
○Cerebrospinal fuid (CSF) drainage.
○Direct measurement of intracranial pressure.
•Subarachnoid/intraventricular hemorrhage.
•Intraoperative brain relaxation.
•CSF infection.
50.2 Frontal Horn (Kocher’s Point) (Fig. 50.1)
50.2.1 Patient Positioning
•Position: The patient is positioned supine.
•Head: The head is slightly fexed (30°), in neutral position.
50.2.2 Skin Incision
•Side: The side is usually the nondominant (unless clinically indicated).
•Starting point: Incision starts about 3 cm lateral to midline, over the coronal suture (usually located 11–13 cm along the nasion-to-inion line) or just posterior to it.
•Course: It runs straight anteriorly, parallel to the midline.
•Ending point: It ends about 2 cm anterior to the coronal suture.
50.2.3 Craniectomy
•Burr hole
○The burr hole is made about 2.5–3 cm lateral to the midline, 1 cm anterior to the coronal suture.
Critical Structures
•Arachnoid granulations.
•Dural venous lakes.
•Underlying brain parenchyma.
50.2.4 Dural Opening
•The dura is opened in a cruciate fashion.
•Bipolar electrocautery is used for dural opening.
Critical Structures
• Venous lakes and bridging veins.
50.2.5 Intradural Exposure and
Catheter Insertion
•The cortical surface is coagulated with bipolar electrocautery.
•The catheter is directed perpendicularly to the cortical surface by aiming in the coronal plane, toward the medial
Fig. 50.1 Kocher’s point.
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VII Ventricular Shunts Procedures
canthus of the ipsilateral eye and in the antero-posterior plane toward the tragus.
•The catheter is advanced with the stylet until CSF comes out (5-6 cm in depth; it might be less with markedly dilated ventricles).
•The catheter is further advanced without stylet for about 1 cm.
50.2.6 Critical Issues
•The stylet has not to be advanced for more than 7 cm.
•If CSF does not come out, following aspects have to be taken into consideration:
○Wrong site of burr hole or incorrect direction of catheter insertion.
○Slit ventricles.
○Brain shift.
○Air entrance in ventricles.
○Catheter obstruction by brain tissue, blood clot, or air lock.
•Intra-cerebral hematomas along catheter’s path.
•Intraventricular bleeding from choroid plexus.
50.3 Alternative Access To The Frontal Horn
50.3.1 Kaufman’s Point (Supraorbital) (Fig. 50.2)
•Entry point: Catheter entry point is 4 cm above the orbital rim and 3 cm lateral to the midline.
•Direction: The stylet is directed toward the midline.
•Depth: The stylet must be advanced for 6-7 cm.
•Ventricular target: Ventricular target corresponds to the frontal horn. Occipital horn can be reached by the same trajectory.
•Advantage: Accuracy rate might exceed that of Kocher access.
•Critical issues: Minimal cosmetic defcit.
50.3.2 Transorbital (Fig. 50.3)
•Technique:
○Superior eyelid has to be retracted forward and upward.
○Ocular globe is displaced downward.
•Entry point: A 18-gauge spinal needle is placed in the rostral third of the orbital roof (1 cm behind the supra-ciliar arch), just medial to the mid-pupillary line.
•Direction: The stylet is directed 45° according to the axial plane (orbito-meatal line) and 15–20° medial to a vertical line (cranio-caudal line).
•Depth: The stylet must be advanced from 3 to 8.5 cm, according to the ventricular size.
•Ventricular target: Ventricular target corresponds to the frontal horn (1–2 cm superior to the foramen of Monro).
•Critical issues:
○Risk of damage at supraorbital neurovascular bundle, or frontal lobe vessels.
○Intra-orbital CSF leakage.
50.4 Occipital Horn
50.4.1 Patient Positioning
•Supine position
○Head: The head is fexed 15-20°, rotated as much as possible to the contralateral side.
○Possible positioning of a roll under the ipsilateral shoulder.
•Prone position
○The patient is prone, in neutral position.
Fig. 50.2 Kaufman’s point.
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50 Anthropometry for Ventricular Puncture
Fig. 50.3 Transorbital point.
Abbreviations: MPL = mid-pupillary line.
Fig. 50.4 Keen’s point.
50.5 Alternative Access to the Occipital Horn and Trigone
50.5.1 Keen’s Point (Posterior Parietal) (Fig. 50.4)
•Entry point: Catheter entry point is 2.5-3 cm posterior and 2.5–3 cm superior to the top of the pinna.
•Direction: The stylet is directed perpendicular to the cerebral cortex.
•Depth: The stylet must be advanced 4-5 cm.
•Ventricular target: Ventricular target corresponds to the atrium.
50.5.2 Dandy’s Point (Occipital) (Fig. 50.5)
•Entry point: Catheter entry point is 3 cm above the inion and 2 cm lateral to the midline; it is placed on the occipital side of the lambdoid suture (in infants usually matches with lambdoid suture at intersection with mid-pupillary line).
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VII Ventricular Shunts Procedures
Fig. 50.5 Dandy’s point.
Fig. 50.6 Frazier’s point.
•Direction: The stylet is directed perpendicular to the cortex.
•Depth: The stylet must be advanced 4-5 cm.
•Ventricular target: Ventricular target corresponds to the occipital horn.
•Critical issues: Signifcant risk of damaging visual pathways.
•Direction: The stylet is directed perpendicular to the cortex, toward the omolateral medial canthus.
•Depth: The stylet has to be advanced 4-5 cm.
•Ventricular target: Ventricular target corresponds to the atrium.
50.5.3 Frazier’s Point (Occipital) (Fig. 50.6)
•Entry point: Catheter entry point is 3-4 cm from the midline and 6-7 above the inion; it is placed at the parietal side of the lambdoid suture.
50.5.4 Targeted Procedures
•Stereotactic (frame-based) placement
•Endoscopic placement
•Ultrasound-guided procedure
•Neuronavigation-guided (frameless) procedure
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50 Anthropometry for Ventricular Puncture
Fig. 50.7 Paine’s point.
50.6 Intraoperative Positioning of |
2. |
Greenberg MS. Handbook of neurosurgery. New York: |
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Ventricular Shunts |
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Thieme Medical Publishers;2010. |
3. |
Madrazo Navarro I, Garcia Renteria JA, Rosas Peralta VH, |
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50.6.1 Paine’s Point (Fig. 50.7) |
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Dei Castilli MA. Transorbital ventricular puncture for |
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emergency ventricular decompression. Technical note. |
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• Entry point: Catheter entry point is inserted at the right |
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Mortazavi MM, Adeeb N, Griessenauer CJ, et al. The ven- |
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angle formed by the intersection of the lines measuring |
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2.5 cm superior from the foor of the anterior cranial fos- |
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history, anatomy, histology, embryology, and surgical con- |
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5. |
Park J, Hamm IS. Revision of Paine’s technique for intraop- |
• Direction: The stylet is directed perpendicular to the cortex. |
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• Depth: The stylet must be advanced 4–5 cm. |
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508, discussion 508. |
• Ventricular target: Ventricular target corresponds to the |
6. |
Schmidek HH, Sweet WH. Operative Neurosurgical Tech- |
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niques. 6th ed. Vol. 2. Philadelphia: Elsevier/Saunders;2012. |
• Critical issues: |
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Sekhar LN, Fessler RG. Atlas of neurosurgical techniques. |
○ Proximity to the Broca's area in the dominant hemisphere. |
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Brain. Vol. 1. New York: Thieme Medical Publishers;2016. |
○ Violation of the head of the caudate nucleus. |
8. |
Tubbs RS, Loukas M, Shoja MM, Cohen-Gadol AA. Emergen- |
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cy transorbital ventricular puncture: refnement of exter- |
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