Abstract
We present a case of a cavernous sinus dural arteriovenous fistula (CS−dAVF) with concomitant multiple brain metastases (MBM) that showed hemodynamic alteration of the shunt after irradiation of the MBM. A 78-year-old woman with a history of breast cancer (cT2N1M1 Stage IV) presented to the clinic for further evaluation and treatment of multiple brain lesions identified on magnetic resonance imaging (MRI). She was diagnosed with breast cancer (cT2N1M1 Stage IV) one year before presenting to our clinic. The patient underwent surgery and adjuvant chemotherapy. Although the visceral malignancy remained dormant, the patient’s condition was complicated by MBM. Proptosis and ophthalmoplegia occurred, and head MRI indicated CS-dAVF. Radiotherapy targeting the metastatic brain tumors was performed. Cerebral angiography at 40 days post-irradiation showed CS-dAVF draining into the external jugular vein via the facial vein (FV), superior orbital vein (SOV), and superficial temporal vein (STV). On the 77th day after radiotherapy, transvenous coil embolization was planned for the CS-dAVF. Preoperative angiography showed decreased flow in both feeders and drainers. Although the angiographic changes were demonstrated, her ophthalmoplegia had progressed, which we concluded was a typical “paradoxical worsening.” Due to hemodynamic alteration, we were obliged to access the CS via the obstructed inferior petrosal sinus. Coil embolization was performed as planned, and the symptoms gradually improved without recurrence within 18 months. The drastic change in hemodynamics that we observed in this case may be explained by the radiotherapy performed in advance against MBM. Although rare, possible changes in hemodynamic flow should be considered during treatment planning when MBM is comorbid with CS-dAVF.
