Simpson grade
Extent of surgical meningeoma resection
Grade 1
Macroscopically complete removal, including excision of dural attachment and abnormal bone.
Grade 2
Macroscopically complete removal, with coagulation of the dural attachment.
Grade 3
Macroscopically complete removal, without coagulation of dural attachment / extradural extensions (abnormal bone).
Grade 4
Partial removal.
Grade 5
Biopsy or decompression only.Reference
Greenberg's Handbook of Neurosurgery, 7th edition
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