026 positioning for cranial surgery

Youmans Neurological surgery 6th

1. Positioning for cranial surgery
Youmans Chapter 26

2. Outline
•Pterional (frontotemporal) craniotomy
•Temporal and subtemporal approach
•Anterior parasagittal and subfrontal approaches
•Posterior parasagittal craniotomy
•Midline suboccipital craniotomy
•Lateral suboccipital approach
•Transsphenoidal approach

3. Pterional (frontotemporal) craniotomy

4. Pterional (frontotemporal) craniotomy
•Most common
•Approach
–supratentorial intracerebral aneurysms
–pathologic processes of the anterior, middle cranial
fossae and posterior cranial fossa
–the central skull base

5. Pterional (frontotemporal) craniotomy
•Positioning
–Supine position, reverse Trendelenburg
–Mayfield-Kees head fixation
•The single pin is placed in the frontal bone
contralateral to the operative target,
approximately 2 to 3 cm above the brow
•The dual pins are then placed in the occipital bone
on the ipsilateral side
•Pins along the axial plane, may be saggital plane
–Shoulder roll is placed under the ipsilateral
shoulder along axis

6. Pterional (frontotemporal) craniotomy
•Position
–Head
•Head is rotate toward the contralateral shoulder
•The degree of rotation can vary greatly and is
largely dependent on the desired surgical
target
•internal carotid artery disease : 5-20
o
•anterior communicating artery aneurysms : 60
o
•wide opening of the sylvian fissure : avoidance
of excessive rotation
•head is laterally flexed slightly, followed by an
extension of the neck

7. Pterional (frontotemporal) craniotomy
•Position
–This last maneuver should present the malar
eminence as the highest point
–Once it is in position, the head fixation device is
secured to the table
–Pillows and padding are placed under the
patient’s knees and feet
–patient is secured to the table with a padded safety
belt or padding and tape

8. Temporal and subtemporal approach

9. Temporal and subtemporal approach
•Perform alone for petrous disease, other
disease of the middle fossa, or basilar apex
aneurysms
•Performed in conjunction with another approach,
such as the pterional or lateral suboccipital
craniotomy

10. Temporal and subtemporal approach
•Position
–lateral park bench position, reverse Trendelenburg
position
–Mayfield-Kees head fixation
•The single pin clamp into the frontal bone 2 to 3
cm above the ipsilateral brow
•The dual pins in the occipital bone along the
axial plane at midline and contralateral to the
surgical site

11. Temporal and subtemporal approach
•Position
–Arms
•inferior arm extended perpendicular to the patient’s
body on an arm board
•dependent arm is properly positioned
•placed in neutral position along the long axis of the
torso, with slight flexion at the elbow
–the neck is laterally flexed

12. Temporal and subtemporal approach
•Position
–The head fixation apparatus is then secured to the
table, and the patient’s body is supported with safety
belts and tape
–Alternatively, the temporal or subtemporal approach
can be accomplished with the patient in the supine
position as long as the patient’s neck is supple and
90 degrees of rotation can be accomplished
easily.

13. Anterior parasagittal and
subfrontal approaches

14. Anterior parasagittal and
subfrontal approaches
•Different in degree of head flexion
•The anterior parasagittal approach
–interhemispheric approaches : lesions of the anterior
interhemispheric fissure, distal anterior cerebral
artery aneurysms, access to the third or lateral
ventricles for colloid cysts ,intraventricular disease
•The subfrontal approach
–anterior cranial fossa : meningiomas from the
olfactory groove to the tuberculum sellae

15. Anterior parasagittal and
subfrontal approaches
•Position
–Supine
–Mayfield-Kees head fixation
•The dual pins are placed behind the ear in
the coronal plane
•the single pin is placed at approximately the same
point on the contralateral side
–the patient is strapped in with a waist belt
–the head of the bed is raised until the vertex of the
patient’s head is within the focal length of the
neurosurgeon

16. Anterior parasagittal and
subfrontal approaches
•Position
–For the anterior parasagittal craniotomy, the head is
flexed until the point of the planned craniotomy and
the planned target are along a comfortable
trajectory for the neurosurgeon
–For the subfrontal approach, it is often necessary to
actually extend the head slightly until the brow is
the most superior point on the operative field
–The head is secured. The patient is then secured to
the table with pressure points padded as outlined
before

17. Anterior parasagittal and
subfrontal approaches
•Position
–An alternative positioning strategy for the anterior
parasagittal approach is to have the patient in a
lateral position, with the side down depending on the
pathologic process and the angle of attack
–The head is then tilted upward until the surgical target
is in the appropriate location, placing the pathologic
process in the horizontal plane
–Use for : parasagittal meningiomas, contralateral
hemisphere through a transcallosal approach

18. Posterior parasagittal craniotomy
•Supine position
–Craniotomy is within several centimeters posterior
to the cranial vertex, awake craniotomy
–Mayfield-Kees head clamp
•the pins oriented in the axial plane
•the posterior of the dual pins approximately 2 to
3 cm above the external auditory meatus
•the single pin slightly anterior to this point on the
opposite side.

19. Posterior parasagittal craniotomy
•Supine position
–the bed is flexed slightly until the site of the
craniotomy is in the desired position
–If an awake craniotomy is planned, the neck should
remain in neutral position, with the thighs typically
elevated to increase the patient’s comfort

20. Posterior parasagittal craniotomy
•Prone position
–the pins are placed before the patient is flipped
–Mayfield-Kees head clamp
•the pins oriented in the axial plane
•the posterior of the dual pins approximately 2 to
3 cm above the external auditory meatus
•the single pin slightly anterior to this point on the
opposite side.
–Patient placed prone on the operative table

21. Posterior parasagittal craniotomy
•Prone position
–arms are placed in the neutral position and are
padded and tucked to the patient’s side
–The patient’s chest lies on soft gel rolls placed parallel
to the long axis of the body
–It is important to avoid leaving electrocardiogram
leads or wires on or across the anterior chest wall
because this can produce pressure sores or
abrasions

22. Posterior parasagittal craniotomy
•Prone position
–Once the patient is strapped in, the bed is flexed
into the Concorde position
–the final manipulation entails extension or flexion of
the neck. The degree of flexion depends on the exact
location of the planned craniotomy

23. Midline suboccipital craniotomy

24. Midline suboccipital craniotomy
•Approch
–Fourth ventricular lesion
–midline cerebellar lesions
–Pineal lesion

25. Midline suboccipital craniotomy
•Prone position
–Mayfield-Kees head fixation
•the pins just below the superior temporal line
on both sides
•The dual pin side is typically placed so that the
posterior pin is 2 to 3 cm above the external
auditory meatus;
•The single pin is placed slightly anterior at the
same level on the contralateral side

26. Midline suboccipital craniotomy
•Prone position
–The patient is placed prone on the operative table
onto two large chest rolls, and the arms are
tucked into neutral position along the length of the
patient
–The patient is strapped to the bed with a waist belt
–Concorde position and reverse Trendelenburg
–the head is flexed until the chin is at least two
fingerbreadths from the sternal notch
–craniotomy site is the most superior point of the
patient

27. Midline suboccipital craniotomy
•Seated position
–supracerebellar infratentorial position
–the cerebellum falls away from the tentorium after
arachnoidal adhesions are divided, and it provides a
bloodless field

28. Midline suboccipital craniotomy
•Mayfield-Kees head fixation
–the pins just below the superior temporal line on
both sides
–The dual pin side is typically placed so that the
posterior pin is 2 to 3 cm above the external auditory
meatus;
–The single pin is placed slightly anterior at the same
level on the contralateral side

29. Midline suboccipital craniotomy
•Seated position
–The patient is strapped in with a waist belt, and the
back is elevated until the patient is in the seated
position
–The head is then flexed slightly before the
Mayfield-Kees head clamp is secured
–The arms are then placed across the patient’s
abdomen and secured
–The lower extremities are often wrapped in
compression stockings or wrap to facilitate venous
return

30. Lateral suboccipital approach

31. Lateral suboccipital approach
•Approach
–cerebellopontine angle
–lateral cerebellum
–posterior circulation aneurysms
–aneurysms of the anterior inferior cerebellar artery
–microvascular decompression of the trigeminal nerve

32. Lateral suboccipital approach
•number of positions
–modified Concorde position
–lateral park bench position
–supine position
–seated position

33. Lateral suboccipital approach
•modified Concorde position
•the patient is positioned exactly as with the midline
suboccipital approach
•Modified by rotation of the patient’s head
approximately 45 degrees to the shoulder ipsilateral
to the lesion before the head is fixed in the Mayfield
clamp

34. Lateral suboccipital approach
•The park bench position
–The patient is positioned as described for the
subtemporal craniotomy
–rotating the face slightly toward the floor
–the Mayfield-Kees head clamp is parallel to the
floor and presents the craniotomy site as the
most prominent part of the operative field
–It is important to pad pressure points and to add
an axillary roll as described for the temporal or
subtemporal approach

35. Lateral suboccipital approach
•sitting position
–Mayfield-Kees head fixation
•the dual pins are placed 2 to 3 cm above the
external auditory
•the single pin is placed 2 to 3 cm superior and
anterior to the external auditory meatus
–The patient is strapped in with a waist belt, and the
back is elevated until the patient is in the seated
position
–The bed is then flexed, with an elevation of the thighs
and flexion of the knees

36. Lateral suboccipital approach
•sitting position
–The arms are then placed across the patient’s
abdomen and secured
–The head is then flexed slightly and rotated,
depending on the pathologic process at hand, before
the Mayfield-Kees head clamp is secured

37. Lateral suboccipital approach
Advantage Disadvantage
modified Concorde
position
-comfortable for the
surgeon
-cerebellopontine angle
disease (gravity aid)
-risk of air embolus
-risk of pressure sores
and blindness from
elevated intraocular
pressures
park bench
position
-facilitates cerebellar
retraction
-comfortable position for
the operating surgeon
-brachial plexus injuries
-other stretch injuries
sitting position-lowering intracranial
pressure
-the anesthesiologist
superior access to the
face
- clear, bloodless field
-higher risk of venous air
embolism
-tension pneumocephalus
-subdural hematomas
-can create fatigue for the
surgeon operating

38. Transsphenoidal approach

39. Transsphenoidal approach
•It is imperative that the patient be positioned
correctly, ensuring that the correct trajectory is
taken
•Complication : opening of the anterior cranial
fossa

40. Transsphenoidal approach
•Positioning for the endoscopic endonasal
approach
–Supine position
–The head is placed on a horseshoe headrest,
–the right arm is tucked with the hand positioned
underneath the right thigh
–The patient is then strapped in by a belt across the
thighs
–The bed is turned so that the feet are
approximately 30 degrees to the patient’s left in
relation to the head

41. Transsphenoidal approach
•Positioning for the endoscopic endonasal
approach
–the bed is flexed into a beach chair position
–reverse Trendelenburg positioning
–The bed is then tilted slightly to the right
–the bridge of the nose parallel to the floor

42. Transsphenoidal approach
•Positioning for the sublabial microscopic
approach
–Supine position
–The arms are tucked, and the patient is again belted
in with a strap across the thighs
–The patient is placed in the Mayfield-Kees pins
–The pins are placed behind the ears to reduce
potential obstruction of fluoroscopic images

43. Transsphenoidal approach
•Positioning for the sublabial microscopic
approach
–Before the head is secured, the head of the bed is
elevated
–The head is then flexed until the bridge of the nose is
approximately 45 degrees from the horizontal axis
–The head is rotated to the patient’s right until the
patient is face-to-face with the surgeon before the
Mayfield is finally locked in

44. Thank you