1. Technical considerations of decompressive craniectomy
DR AMIT KUMAR GHOSH
CONSULTANT NEUROSURGEON
GLOBAL HOSPITAL AND HEALTH CITY

2. Introduction
Decompressive craniectomy, which is performed worldwide for the treatment of severe traumatic brain injury (TBI), is a surgical procedure in which part of the skull is removed to allow the brain to swell without being squeezed.
1901, Kocher was the first surgeon to promote surgical decompression in post-traumatic brain swelling.

3. Temporal fascia or synthetic Dura
MATERIAL AND METHODS
300 decompressive craniectomies for head injuries following Shima K, 2004.
Temporal fascia or synthetic Dura

4. Discussion
Aims and objectives of surgery-Giving room to the swelling brain , decreases compression of brain stem structures and minimizes herniation .(Kerr FWL; 1968)
Reduce ICP
Improve cerebral blood flow and thus reduce secondary brain injury
Concept of decompressive craniectomy is supported by the Monro-Kellie doctrine.
The brain is a soft organ housed in a stiff box (the skull).
Apart from the brain substance, this box also houses arterial and venous blood and cerebrospinal fluid. Any increase in any one of these components will result in a shift of any other component from the box or increased pressure within the box (ICP- intracranial pressure). Small changes in volume can result in big changes in pressure and decreasing the amount of arterial blood getting into the brain (CPP or cerebral perfusion pressure)
Thus,decompressive craniectomy is to increase the size of the box so that the extra volume can be accommodated.
Thus “ a life-saving procedure.” -

5. DISCUSSION TECHNICAL CONSIDERATIONS ( TYPE OF SCALP INCISIONS)
2nd optional flap
Classical ‘Question mark” trauma flap
It is also recommended, although not absolutely essential:
For diffuse brain swelling to use a bicoronal flap with bifrontal decompressive craniectomy with bilateral U-shaped opening of the dura, based on the superior sagittal sinus and with ligation and division of the sinus and falx anteriorly for maximum decompression of the frontal regions. The frontal sinus, if inadvertently opened during craniectomy, should be cranialized (excision of posterior wall, stripping of mucosa and plugging of osteum with the pericranium and/or free muscle and/or tissue glue)
Bicoronal flap
RESCUEicp study (Randomised Evaluation of Surgery with Craniectomy for Uncontrollable Elevation of Intra-Cranial Pressure)

6. DISCUSSION-- Technical considerations---
(Extent of Craniectomy in different study)
Wide craniectomy > 12 cm diameter which descends down to temporal fossae and posteriorly upto Asterion ( Romanian Neurosurgery)
Large (10 × 15 cm) frontotemporoparietal Craniectomy with the lower margin upto the middle cranial fossa( Shima K 2004)
Wide (≥12 cm in diameter) decompressive craniectomy
( RESCUEicp Study)
Technical considerations(Dural Opening described in literature)
stellate
C-shaped dural opening
4-flap

7. DISCUSSION-- Methods of Duraplasty Duraplasty
Decompressive craniectomy + Dural opening (could maximize brain expansion) +augmentative duraplasty (recommended by most authors)
SHOWED
better outcomes and lower incidences of secondary surgical complications like brain herniation through the craniectomy defect, epilepsy, intracranial infection, and cerebrospinal fluid (CSF) leakage through the scalp incision or contralateral intracranial lesion compared with those who only underwent surgical decompression, leaving the dura open (Keeping the dura open with no protection for the underlying brain tissue may increase the risk of these complications (Yang et al.)
Methods of Duraplasty
The dura is enlarged with the patient's own tissue, such as temporal fascia,
temporal muscle, or galea aponeurotica or with artificial material
Yu et al described separation of the temporal deep fascia from the temporal muscle to the zygomatic arch, and then cut the fascia from the base backwards along the zygoma but left the fascia base 1-2 cm long for the blood supply. Finally, they turned the temporal fascia beneath the temporal muscle and sutured it to the dura.

8. DISCUSSION—(Some other technical considerations)
Coskay et al described “ vascular Tunnel” method to prevent brain herniation via the craniectomy defect which may lead to compression of vessels and result in ischemic necrosis of the portion of the herniated brain
Dural incisions in a stellate fashion. And then keeping haemostatic sponge supporting vessels in between dura and brain.
Another method, Lattice duraplasty, was also introduced by Mitchell et al. to avoid herniation of the brain through the cranial defect. After conventional craniotomy, they made a series of dural incisions, each 2 cm long and with 1-cm intervals. The process was repeated in parallel rows of incisions so that each incision in one row was adjacent to an intact dural bridge in the rows on either side. The same course was then performed, but in a direction vertical to the initial incision.
Vakis et al. introduced a method to prevent peridural fibrosis after decompressive craniectomy
The tucci flap” was suggested by Claudia et al. Similar technique was introduced by Kathryn et al., but was called an “in situ hinge craniectomy”
Zhang et al. suggested a method of surgical decompression combined with removal of part of the temporal muscle to increase the space of decompressive craniectomy.However, survivors developed a higher rate of mastication disability.

9. DISCUSSION—(Some other technical considerations)
Peethambaran AK, Valsalmony J. Four-quadrant osteoplastic decompressive craniotomy: A novel technique for decompressive craniectomy avoiding revision cranioplasty after surgery. Neurol India 2012;60:672-4
In case of massive cerebral swelling, duraplasty as well as internal decompression is performed.
Multi-dural stabs or SKIMS-Technique---Bhat AR, Kirmani AR, Wani MA. Decompressive craniectomy with multi-dural stabs – A combined (SKIMS) technique to evacuate acute subdural hematoma with underlying severe traumatic brain edema. Asian Journal of Neurosurgery. 2013;8(1): doi: /
CONCLUSION
During any decompressive craniectomy, It must be emphasized about the adequate extent of bone removal, dural opening and duraplasty according to the available literature to get the best results and to prevent complications