Not true regarding sub dural haematoma

Acute subdural haematoma Acute subdural haematoma encountered in two broadly distinct contexts. Firstly, high-energy injury mechanisms can result in the rupture of coical surface vessels with significant associated primary brain injury. This results in expanding haematoma with rapid deterioration anddeveloping signs of raised ICP, reminiscent of extradural haematoma without the lucid interval. These collections require prompt evacuation, typically by craniotomy or craniectomy. In a second group of patients, older and often anticoagulated, a lower-energy injury leads to venous bleeding around the brain. Depending on the total volume of bleeding, the resulting haematoma may present early as acute subdural haematoma, after delay and osmotic expansion as chronic sub- dural haematoma or may even remain clinically silent. This latter group may present much later with a fuher 'acute-on- chronic' subdural haematoma. On diagnosis, clotting function should be corrected wherever possible. Bleeds of significant size, with significant associated midline shift or with deteriorating neurology, require urgent evacuation. Smaller bleeds in neurologically stable patients may be managed conservatively, at least initially: liquefaction of the clot over 7-10 days after the bleed may allow for a much less invasive evacuation through burr holesSince the dura is not adherent to the brain as it is to the skull, subdural blood is free to expand across the brain surface giving a diffuse concave appearance. Ref: Bailey and love 27th edition Pg no : 334