Simpson grading
Classification system for extent of meningioma resection, ranging from Grade I (complete with dural attachment) to Grade V (simple decompression).
Full Definition
The Simpson grading system is a standardized classification for assessing the completeness of meningioma resection, developed by Donald Simpson in 1957. The system ranges from Grade I (complete removal of tumor, dural attachment, and abnormal bone) to Grade V (simple decompression or biopsy). Grade I represents the most complete resection with lowest recurrence risk, while higher grades indicate increasing amounts of residual tissue and correspondingly higher recurrence rates. This grading system is crucial for predicting tumor recurrence, planning follow-up surveillance, and determining the need for adjuvant radiation therapy. The classification helps standardize surgical reporting and enables comparison of outcomes across different institutions and studies.
Usage
Usage note: Always capitalized; Roman numerals I-V used for grades.
In Context
- "Simpson Grade I resection was achieved with complete removal of the dural tail." — operative report
- "The Simpson Grade III resection necessitates close radiographic surveillance for recurrence." — postoperative planning