MR imaging evolution of ESBR from the immediate postoperative period to stability on follow-up
| Immediate Postoperative MRI | Follow-Up MRI at 2–6 Months | |
|---|---|---|
| NSF | Solid enhancement, T2-isointensity to brain (mostly similar to gray matter), distinctive C shape and vascular pedicle configurations | Persistent solid enhancement, persistent T2-isointensity to brain (mostly similar to gray matter), thickness reduction by 20%–30%, average thickness of 4.5 mm |
| Less well-defined C shape and vascular pedicle configurations, unchanged flap location | ||
| Fascia lata | Nonenhancing, variable T2 signal intensity | Mildly enhancing, increasing T2-hypointensity, thickness reduction by ≥50%, average thickness of 3.5 mm |
| Collagen matrix dural graft | Nonenhancing, nonvisible to ≤2 mm | Inseparable from enhancing granulation tissue at the reconstruction site, nonvisible to ≤2 mm |
| Fat graft | Fat signal intensity fills intracranial surgical bed | Fat signal intensity in retracted intracranial surgical bed, progressive resorption with volume reduction by ≥50% |