Sindou Grading System for Cavernous Sinus Meningiomas
The Sindou Grade is a classification system used to assess the extent of resection and postoperative outcomes in patients undergoing surgery for cavernous sinus meningiomas (CSMs). It was developed by Marc Sindou to provide a standardized way to evaluate surgical results.
**Sindou Grades (I-VI)**
| Grade | Extent of Resection | Description |
|---|---|---|
| Grade I | Total Resection (100%) | Complete tumor removal, including dural attachment and invaded bone. |
| Grade II | Subtotal Resection (>90%) | Small residual tumor in non-critical areas. |
| Grade III | Partial Resection (50-90%) | Significant tumor removal, but residual tumor remains in critical structures. |
| Grade IV | Limited Resection (<50%) | Only a portion of the tumor is removed due to high surgical risk. |
| Grade V | Biopsy or Decompression | Minimal resection, only for symptom relief. |
| Grade VI | No Resection | Tumor is deemed inoperable. |
**Clinical Implications**
- Higher grades (I-II) are associated with better prognosis but may carry a higher risk of cranial nerve deficits. - Lower grades (IV-VI) suggest incomplete resection, often due to tumor invasion into critical neurovascular structures. - Adjunctive treatments, such as radiosurgery (Gamma Knife, CyberKnife), are often considered for residual or inoperable tumors (Grade III-VI).
Example Interpretation: - A patient with Grade I resection has a complete tumor removal and a lower risk of recurrence. - A patient with Grade IV resection has a high residual tumor burden, requiring adjuvant therapy.
References: - Sindou M. et al. “Resection of cavernous sinus meningiomas: A grading system and evaluation of surgical results.” *Neurosurgery*, 2002.