Simpson grade

The Simpson grade of meningioma resection was described in 1957 and correlated the degree of surgical resection completeness with symptomatic recurrence .

Although the type of resection still plays a part in the likelihood of symptomatic recurrence, other factors (such as the MIB-1 index) are also important, particularly in grades I - III .

  • grade I
    • complete removal including resection of underlying bone and associated dura
    • 9% symptomatic recurrence at 10 years
  • grade II
    • complete removal and coagulation of dural attachment
    • 19% symptomatic recurrence at 10 years
  • grade III
    • complete removal w/o resection of dura or coagulation
    • 29% symptomatic recurrence at 10 years
  • grade IV
    • subtotal resection
    • 44% symptomatic recurrence at 10 years
  • grade V
    • simple decompression with or without biopsy
    • 100% symptomatic recurrence at 10 years (small sample in original paper)