Craniotomy is a surgical procedure involving the temporary removal of a portion of the skull to access the brain for various intracranial operations, primarily indicated for brain injuries, tumors, hemorrhages, and vascular malformations. Different types of craniotomy exist based on location and technique, including minimally invasive approaches to reduce recovery time and complications. The procedure involves several critical steps and carries risks such as bleeding, infection, and neurological deficits.

1. Craniotomy
Presenter – Rahul Sharma

2. Learning Objectives
• What is Craniotomy?
• What are the Indications for Craniotomy?
• What are the Types of Craniotomy?
• Equipment used in craniotomy?
• What happen to the Bone flap?
• What are the Tests Done Prior to Craniotomy?
• What happens during surgery?
• What are the risks?
• References

3. Historical context and Perspective
• Dating back to 2300 years , trephination is the oldest
cranial surgical technique.
• End of 19th century self-educated surgeon Wilhelm
Wagner introduce current modern surgical technique
for a craniotomy for the final cured result.

4. What is Craniotomy?
• It is a Surgical procedure
• A part of skull is
temporarily removed to
expose the brain and
perform an intracranial
procedure.

5. Indications
Brain injury following trauma is one of commonest
indications for craniotomy.
• Craniotomy usually done for Surgical removal of a tumor
or blood clot (hematoma)

6. Clipping of an aneurysm
• Clipping of aneurysm reduces blood flow through it
and therefore decreases its size and its potential to
burst.

7. Removal of an Arteriovenous Malformation
• Abnormal communication
between an artery and a
vein
• Bleeding can result in
grave consequences.

8. Ventricular shunting
• Procedure performed to reduce pressure in the skull
due to excess fluid accumulation.

9. Other indication can be:-
1. Decompressive by draining abscess
2. Lobectomy
3. Epilepsy surgery
4. Craniosynostosis
5. Cerebrospinal fluid leak repair
6. Other procedures like inserting deep brain
stimulators for the treatment of conditions
Parkinson’s disease, essential tremor and dystonia

10. What are the Types of Craniotomy?
• It can be classified into several types depending on
location.
Frontal craniotomy
Temporal craniotomy
Parietal craniotomy
Occipital craniotomy
Pterional craniotomy

11. Extended Bifrontal Craniotomy
• Traditional skull base
approach
• Incision given in scalp
behind the hairline
• Target difficult tumors at
frontal part of brain
• Bone remove forms
contour of orbits and
forehead

12. Principle behind bifrontal craniotomy
• Allows surgeons to work in space between and right
behind eyes without having to unnecessarily
manipulate the brain
Indication
Mainly those tumors not exposed by minimal invasive
approaches including,
• Meningiomas
• Esthesioneuroblastomas
• Malignant skull base tumors

13. Minimally Invasive Supra-Orbital “
eyebrow” Craniotomy
• Small incision made within
eyebrow
Helps to access
• Tumors in front of brain
• Pituitary gland tumor
• Tumors deeper in brain behind
nose and eyes
• Approach used instead of
endonasal endoscopic surgery
if tumor size is large or close to
optic nerve or vital arteries

14. it is a minimally invasive procedure, supra-orbital
“eyebrow” craniotomy may offer
• Less pain than open craniotomy
• Faster recovery than open craniotomy
• Minimal scarring
Mainly used for
1. Rathke’s cleft cysts
2. Skull base tumors
3. Pituitary tumors

15. Retro-Sigmoid “Keyhole” Craniotomy
• Minimally -invasive surgical
procedure
• A small incision behind the ear
• Providing access to cerebellum
and brainstem
• Approach used to reach acoustic
neuromas (vestibular
schwannomas)

16. Translabyrinthine Craniotomy
• Incision in scalp behind the
ear
• Mastoid bone and some of
the inner ear bone remove
• Considered for removal of
acoustic neuromas
• Semicircular canals of ear are
removed in order to access
tumor
• Removal of semicircular canal
reduced risk of facial nerve
injury

17. Orbitozygomatic Craniotomy
• Traditional skull base approach
used to target difficult tumors
and aneurysms
• Incision make at scalp behind
the hairline
• bone remove that forms the
contour of orbit and cheek

18. • Brain tumors that treated through Orbitozygomatic
Craniotomy includes
1. Craniopharyngiomas
2. Pituitary tumors
3. Meningiomas

19. Supratentorial craniotomy
• Supratentorial craniotomy means the exposure of
any part of a cerebral hemisphere over the basal line
joining the nasion to the inion.

20. Other types of craniotomies include:
• Keyhole Craniotomy
1. Surgery is carried out
through a small holes
2. Done for lesions that
are not immediately
just below the brain
3. Minimize collateral
damage to surrounding
scalp, brain, blood
vessels, and nerves.

21. Potential advantages of keyhole brain
• Smaller incisions and bony openings (or no incision
is performed through the nostrils – endonasal)
• Less exposure to normal brain structures
• No use of brain retraction with less manipulation of
the brain itself
• Less pain and lower need for narcotics
• Rapid recovery, mobilization, and return to normal
activities
• Discharge from hospital typically within 1 to 2 days
post-surgery

22. Stereotactic Craniotomy
• Uses tiny markers, called fiducials,
instead of a head frame
• MRI or CT scans are taken
• 3D computer model created
• Helps to locate problem area that
needs surgery and display on
computer model

23. Awake Craniotomy
• Patient can be woken up during surgery
• Commonly done for epilepsy surgeries
• lesion is close to a critical area of brain
Indications
• Mass lesion residing motor
and language cortex
• Cortex responsible for other
functions
Benefits
Maximize tumor resection while preserving neurological
function.

24. Equipments
The following are requirements for being able to
perform a craniotomy:
3 –pin skull fixation device

25. High-speed pneumatic cranial drill
(craniotome)
Hudson brace handheld manual drill
Cranial plate fixation tray

26. • What happen to the Bone flap?
In some cases, depending on etiology and indication for
the procedure,
• Bone can be discarded
• Stored in the abdominal subcutaneous space
• Cryopreserved under cold storage conditions

27. Craniectomy
• Bone flap is discarded or not
placed back into the skull
during same operation
• It is usually performed after
a traumatic brain injury.

28. • Decreases intracranial
pressure (ICP),
• Intracranial
hypertension (ICHT)
• Heavy bleeding (also
called haemorrhaging)
inside skull
INDICATION

29. Cranioplasty
• Surgical procedure to
reconstruct and place the
bone flap back into the
skull during a second
intervention

30. What are the Tests Done Prior to
Craniotomy?
• Tests is required to diagnose the pathology
• Helps to locate precisely within the skull
• Routine tests done before any surgery
1. Imaging Tests
CT scan (most common)
MRI
Angiography

31. Routine Tests which are done before any surgery
include:
• Blood tests like hemoglobin levels, blood group
• Liver and kidney function tests
• Blood coagulation test ( Prothromibin time test)
• Urine tests
• ECG

32. Consent form and complete paperwork
• Helps to give medical history
• Inform about any allergies, medicine going on,
previous surgeries
What things patient should take care ?
• Discontinue all NSAIDS(Naproxin, Advil etc)
• Blood thinners ( coumadin, aspirin, etc) 1 week
before surgery
• Stop smoking, chewing tobacco and drinking alcohol
1 week before surgery and 2 week after surgery

33. What happens during Surgery?
• 6 main steps during craniotomy
1. Preparing patient
2. Make a skin incision
3. Perform a craniotomy
4. Expose the brain
5. Correct the problem
6. Close the craniotomy

34. Preparing patient
• No drink & food is allowed
past midnight before surgery
• General anaesthesia
administered
• Head is shaved
• Head is placed in 3 –pin skull
fixation device
• Lumbar drain to remove CSF
fluid

35. Make a skin incision
• Skin is prepared with
antiseptic
• Skin incision marked
• Entire incision area may be
shaved
• Either, Hair –sparing
technique used

36. Perform a craniotomy
• Skin and muscle lifted off and
folded back
• One or more small burr holes
made with drill
• Craniotome to cut outline of
bone flap
• Bone flap lifted and dura mater
exposed

37. Expose the brain
• Opening dura with surgical
scissors
• Folds it back to expose brain
• Retractors placed on brain
• Gently open a corridor to
area needing repair or
removal

38. Correct the problem
• Neurosurgeons use special
magnification glasses called
loupes
• Neurosurgeon used variety of
small tools to cut open and
repair brain tissue
• Some time computer image
guidance system is used
• Used evoked potential
monitoring used to stimulate
specific cranial nerves

39. Close the craniotomy
• Problem removed or repaired
• Retractors holding the brain
are removed
• Dura is closed with sutures
• Bone flap is replaced back by
titanium screws and plates

40. What are the risks?
General complication
1. Bleeding
2. Infection
3. Blood clots
4. Reactions to anesthesia
Specific complications
1. Stroke
2. Seizures
3. swelling of brain, which
may require a second
craniotomy
4. Nerve damage result in
muscle paralysis or
weakness
5. CSF leak
6. Loss of mental functions
7. Permanent brain damage
with associated disabilities
No surgery is without risks

41. Summary
• Craniotomy is a cut that opens the cranium
• A craniotomy may be small or large depending on the
problem.
Indication
• Various neurological diseases
• injuries or conditions such as brain tumors
• Hematomas (blood clots)
• Aneurysms or AVMs
• Skull fractures
• Other reasons for a craniotomy may include foreign
objects (bullets), swelling of the brain, or infection.

42. References
• https://www.iowaclinic.com/webres/File/cran
iotomy.pdf
• Fernández-de Thomas RJ, De Jesus O. Craniotomy.
[Updated 2022 Apr 9]. In: StatPearls [Internet].
Treasure Island (FL): StatPearls Publishing; 2022 Jan-
• https://mayfieldclinic.com/pe-craniotomy.htm

43. Thank You