Superior sagittal sinus meningioma – delayed postoperative, multisession radiosurgery for growing residual

CRANIAL REGION	Superior sagittal sinus
HISTOPATHOLOGY	Meningothelial meningioma, WHO grade 1
PRIOR SURGICAL RESECTION	Yes
PERTINENT LABORATORY FINDINGS	N/A

Case description

A 49-year-old female presented with headaches, speech disorder, and nausea. Magnetic resonance imaging (MRI) demonstrated an 80-cc left frontal parasagittal meningioma ( Figure 12.58.1 ). She underwent initial subtotal resection, and histopathology revealed a meningothelial WHO grade 1 meningioma. Two years after resection, she presented with headaches and short-term memory loss. Follow-up MRI showed tumor progression in the anterior sagittal sinus region, which was treated with Gamma Knife radiosurgery (GKRS) ( Figure 12.58.2 ). The treated tumor remained stable on follow-up. However, tumor progression was noticed outside the treated area in the falx and posterior superior sagittal sinus (SSS) at 18 months and 3 years from surgical resection, respectively. The tumor progression was then managed with three additional radiosurgical procedures (see Figure 12.58.2 ). Due to further tumor progression 6 years later, the patient underwent fractionated intensity-modulated radiation therapy (IMRT) (54 Gy, 30 fractions) as well as a fourth GKRS session. At 18 years after the craniotomy, the patient remained neurologically stable, without any neurological signs or symptoms.

Radiosurgery Machine	Gamma Knife – Model C
Radiosurgery Dose (Gy)	GKRS 1: 13, at the 50% isodose line GKRS 2: 15, at the 50% isodose line GKRS 3: 12, at the 50% isodose line GKRS 4: 14, at the 50% isodose line
Number of Fractions	GKRS 1: 1 GKRS 2: 1 GKRS 3: 1 GKRS 4: 1