Decompressive craniectomy in Traumatic Brain Injury

Decompressive craniectomy

1. Decompressivecraniectomyfor
TBI
Dr. Joe M Das
Senior Resident
Dept. of Neurosurgery

2. •History
•ICP and methods to reduce it
•Definition
•Craniectomyvscraniotomy
•Current evidence
•Indications
•Types
•Procedure
•Complications & their management
•Cranioplasty

3. History
•Ancient Egypt and Greece –TBI, epilepsy,
headache, mental illness
•First described by Annandale (1894)
•Surgical decompression to treat elevated ICP –
Kocher(1901) and Cushing (1905) –
subtemporaland suboccipital
Cushing H. The establishment of cerebral hernia as a decompressivemeasure for inaccessible brain tumors; with the description of
intermuscularmethods of making the bone defect in temporal and occipital regions. SurgGynecolObstet.1905;1:297–314

5. Harvey Cushing spent several months in the lab of Kocher in 1900,
performing cerebral surgery and first encountering the Cushing reflex .

6. •Erlich(1940) –For all head injuries with
persistent coma for more than 24-48 hrs
•Rowbotham(1942) –All traumatic comas
which improved at first and when medical
treatment was ineffective for 12 hrs
•Munro (1952) –If intra-op, the brain was
contused and swollen
•Guerra (1999) –personal results of 20 years –
2
nd
tier therapy in refractory ICP
Guerra WK, GaabMR, Dietz H. et al: Surgical decompression for traumatic brain swelling: indications and results. J
Neurosurg90:187-196, 1999

7. ICP
•In a normal adult, the cranial vault can
accommodate an average volume of
approximately 1500 mL.
•V
Intracranial space= V
Brain+ V
Blood+ V
CSF
•The normal ICP ranges between 10 and 15 mm
Hg in an adult.
•CPP = MAP –ICP
•Systemic hypertension is required to maintain
cerebral perfusion
MonroA (1783). Observations on the structure and function of the nervous system. Edinburgh: Creech & Johnson.
Kelly G (1824). "Appearances observed in the dissection of two individuals; death from cold and congestion of the
brain". Trans Med ChirSciEdinb1: 84–169.

9. Methods to reduce ICP
ACSSurgeryPrinciples & Practice -Section 7 / Chapter 2 Injuries to the Central Nervous System

10. •The limits of well-
tolerated ICP together
with lowering of CPP:
–SAH –18-20 mm Hg
–Malignant Sylvianstroke
–20-22 mm Hg
–Trauma –25 mm Hg
–Slow growing tumors
and HCP –30-40 mm Hg
AschoffA., Schwab S., SprangerM, et al -The value of intracranial pressure monitoring in acute hemispheric stroke,
Neurology 47 (1996): 393-398

11. •A craniectomyof 8 cm 23 ml additional
volume (1.5% of total cerebral volume).
•For real decompression, 12 cm or more (86 ml
additional volume)
•Superior to the one realisedby
hyperventilation (2 mm Hg lowering of pCO2),
ventricular tap of 20-30 ml and without the
risk of loop diuretics.

12. Brain facts

13. Definition
•Decompressivehemicraniectomyand durotomy
is a surgical technique used to relieve the
increased intracranial pressure and brain tissue
shifts that occur in the setting of large cerebral
hemisphere mass, or space-occupying lesions.
•In general, the technique involves removal of
bone tissue (skull) and incision of the restrictive
duramater covering the brain, allowing swollen
brain tissue to herniateupwards through the
surgical defect rather than downwards to
compress the brainstem.

14. Craniotomy vscraniectomy
•Craniotomy–the bone flap is returned to its
previous location
•Craniectomy–the bone flap is not returned

15. Current evidence
•Evidence supporting emergent Decompressive
Craniectomyin Trauma remains controversial
•In animal studies, craniectomyhas been a/w
increased cerebral edema,hemorrhagic
infarcts and cortical necrosis
1
•Decreased ICP
2
•Improved Oxygen tension
2
•Improved cerebral perfusion
2
1.Forsting M, Reith W(1995) ; Wagener S et al(J Neurosurg94:693-696, 2001)
2. BurketW. ZentralblNeurochir50:318-323, 1988; GaabM et al Childs brain 5:484-498, 1979
HatashitaS, J Neurosurg67:573-578, 1987

16. “The role of decompressivecraniectomyin TBI
and in the control of intracranial
hypertension remains a matter of debate.”
YoumansNeurologicalSurgery-Volume 4, Section XI, page 3442

19. Brain facts
•Brain generates 10-23 Watts of electricity
•You have an average of 70,000 thoughts per
day

20. Indications
•Severe TBI
–Heterogeneous lesions in cerebral parenchyma
–Focal (contusions/hematoma) and diffuse
•Malignant MCA infarction
•AneurysmalSAH
•Others
–Central venous thrombosis
–Encephalitis
–Metabolic encephalopathies
–Intracerebralhematoma
NeurosurgClinN Am 24 (2013) 375–391; TarekY. El Ahmadiehet al

21. Indications & Contraindications in TBI
•Indications:
–Coma or semicoma(GCS < 9)
–Pupillaryabnormalities, but respond to mannitol
–Supratentoriallesion with midline shift on CT
–Refractory ICP despite best conventional therapy
–Age: initially < 80 years , now 70 years
(Of patients who were > 70 years, 75% were dead)
•Contraindications:
–Fatal brain stem damage
–GCS < 4 or fixed and dilated bilateral pupils

22. When to perform?
•Bifrontaldecompressivecraniectomyis indicated
within 48 hours of injury for patients with diffuse,
post-traumatic cerebral edema and medically
refractory elevated ICP.
•Subtemporaldecompression, temporal
lobectomy, and hemispheric decompressive
craniectomycan be considered as treatment
options for patients who present with diffuse
parenchymalinjury and refractory elevated ICP
who also have clinical and radiographic evidence
for impending transtentorialbrain herniation.
Bullock MR, ChesnutR, GhajarJ, et al. Neurosurgery 2006;58(Suppl3) Surgical management of traumatic
parenchymallesions. :S25–46 [discus-sion: Si-iv]. -BTF Guidelines

23. Guidelines
•Up to date there are no specific guidelines or protocols
stating exactly when or in what circumstances DC is
appropriate, but there are some recommendations:
1.The North American Brain Trauma Foundation suggests
DC may be the procedure of choice in the appropriate
clinical context and also considering the use of DC in the
first tier of TBI management. (Bullock et al, 2006)
2.European Brain Injury Consortium recommend DC as an
option for refractory intracranial hypertension in all ages.
(Maas et al,1997)
3.A Cochrane review (2006) recommended DC may be
justified in some children with medically intractable ICP
after head injury but concluded there was no evidence to
support its routine use in adults. (Sahuquillo& Arikan,
2006)

24. Types

25. Brain facts
•Stress alters brain cells and function
•Music increases brain organisation

26. Decompressivehemicraniectomy
•Foam / rubber donut
•No pins
•Cervical spine precautions
•Don’t compress the jugulars

27. DHC
•Supine
•Rolled towel beneath ipsilateralshoulder
•Head towards contralateralside
•Mark midline
•Incision –Reverse question mark
•Posterior extent –15 cm behind key hole
•Deepened down to cranium
•Myocutaneousflap reflected
•Five burr holes are made in the following locations: (1)
temporal squamousbone superior to the zygomatic
process inferiorly, (2) keyhole area behind the zygomatic
arch anteriorly, (3) along the superior temporal line
posteroinferiorly, and in the (4) parietal and (5) frontal
parasagittalareas

28. •Smaller craniectomyDamage to cortical veins and
parenchyma
•Dura dissected off from beneath the bone
•Bur-holes connected
•Bone flap removed
•Temporal decompression
•Wax bone edges
•Dural tack-up stitches
•Dural opening (controlled manner) with radial incisions
in stellatefashion
•Closure with duralsubstitute and after keeping suction
drain

35. Brain facts
•2,50,000 neurons are produced per minute in
early pregnancy
•Brain stops growing at around 18 years

36. Bifrontalcraniectomy
•Bifrontalcontusions / diffuse cerebral edema
•Mark midline and coronal suture
•Bicoronalincision (2-3 cm behind coronal)
•Myocutaneousflap brought over the orbital rim (Preserve
supra-orbital nerves)
•Bur-holes –b/lkeys, b/lsquamoustemporal, straddling the
SSS just posterior to coronal suture
•Bone flap
•Temporal decompression
•Bone wax, duraltack-up stitches
•Divide the anterior portion of SSS and falx
•Dural opening wide
KjellbergRN, PrietoA Jr: Bifrontaldecompressivecraniotomy for massive cerebral edema. J Neurosurg34:488-493,
1971

51. What is the percentage reduction in
ICP attained by DC?
•Opening the durahas been shown to improve
the reduction in ICP from 30% (duraleft
intact) to 85% (duraopened)

52. Brain facts
•Dreaming requires more activity than any
waking function
•Oxytocinmakes you feel love

53. Complications
•50-55 %
•Abnormalities in CSF absorption
•Expansion of hematomas after decompression
•Syndrome of the trephined
•Infection

54. CSF absorption disorders
•Subdural hygromas& hydrocephalus
•Causes:
–Ruptured arachnoidOne-way valve
–Pressure gradients between hemispheres
–Alteration in brain’s shape
•Treatment
–Ventriculostomy& oversewingif CSF leak
–VP shunt (programmable)
–Cranioplasty

55. Expanding hematomas
•New or existing mass lesions can
develop postoperatively, especially
given the high incidence of
coagulopathyand platelet dysfunction
•Evolution of both contusions and extra-axial
hematomas can occur after the tamponading
effects of cerebral edema, and elevated ICP has
been relieved by decompressivecraniectomy.
•Postoperative imaging is recommended
especially in the setting of no ICP monitoring

56. SYNDROME OF THE TREPHINED
•Variety of symptoms that can develop following
craniectomy, including fatigue, headache, mood
disturbances, and even motor weakness.
•Mechanisms:
–CSF flow abnormalities
–Direct atmospheric pressure on the brain
–Disturbances in cerebral blood flow.
•Often resolves with replacement of the bone flap
•There is no evidence that it is harmful or that delay of
cranioplastycan result in long-term consequences

57. Cranioplasty
•Usually carried out 6 to 8 weeks after the DC,
assuming that the patient has recovered from the
initial injury and hydrocephalus or brain swelling is not
present.
•In the interim -“hockey helmet”
•Autologousbone flap, (frozen after the initial
surgery / kept in abdominal subcutaneous tissue) is
used and provides good cosmetic results.
•The bone flap remains sterile in a −70°C freezer for
many months.
•Autoclaving of the bone (e.g., if contaminated by a
compound scalp wound before cranioplasty) 
reduce the viability of the graft.

58. Cranioplasty
•Complication associated with abdominal
preservation of bone flap -bone resorption(5-
10%) due to hypovascularbone necrosis and
sepsis of the flap.
•Other materials -methyl methacrylateand
titanium mesh when the bone is heavily
comminuted or contaminated.
•For large, cosmetically important defects, the
use of casts, stereolithographicmodels, and
CT-based “computer-assisted design”
reconstruction technology

60. Conclusion
•IC-HTN results from many disease processes.
•Decompressivecraniectomycan be life
preserving procedure.
•Selection criteria remains in involution.
•Best outcomes are achieved in young patients
treated early in course of disease.