Intracranial pseudoaneurysms are uncommon and among the most difficult lesions to treat with surgery or endovascular means without parent artery sacrifice. Here, we report on a patient who underwent successful treatment using a flow-diverting stent for an iatrogenic intracranial internal carotid artery pseudoaneurysm following a vessel injury after endoscopic pituitary tumor resection via the transsphenoidal approach. A 62-year-old man with a Rathke’s cleft cyst presenting with bitemporal hemianopia and progressive decline of left visual acuity underwent endoscopic transsphenoidal pituitary tumor resection. During dura incision, brisk arterial bleeding was encountered from the right internal carotid artery. Immediate packing was performed, and hemostasis was achieved. Three days after the vessel injury, an angiography revealed a pseudoaneurysm (2.9 × 2.1 mm) at the cavernous segment of the right internal carotid artery, which showed enlargement on follow-up magnetic resonance imaging at six days postoperatively. Pipeline embolization was performed nine days after the vessel injury. Angiography performed one month after Pipeline embolization revealed significant stagnation but not complete occlusion of blood flow inside the pseudoaneurysm cavity. Dual antiplatelet therapy was replaced with single antiplatelet therapy. Follow-up angiograms three months after Pipeline embolization confirmed complete obliteration of the pseudoaneurysm and successful endoluminal reconstruction of the damaged vessel. Despite the possibility of short-term bleeding and the need for dual antiplatelet therapy administration for a certain period, the use of flow-diverting stents is a feasible vessel-sparing option in the management of intracranial internal carotid artery pseudoaneurysms resulting from transsphenoidal surgery injuries if intraoperative hemodynamic stability can be achieved with effective packing.

OBJECTIVE The authors sought to demonstrate that hemorrhagic transformation of ischemic lesions is the main cause of delayed intracerebral hemorrhage (ICH) after Pipeline embolization device (PED) treatment and to estimate the rate of hemorrhagic transformation of new postprocedure ischemic lesions. METHODS Patients who underwent PED placement (PED group) from November 2015 to March 2017 or stent-mediated embolization (EN group) from December 2010 to October 2015 were retrospectively analyzed. Pre- and postprocedural MR images and 6-month follow-up MR images for each patient were scored for the presence of postprocedural bland ischemic and hemorrhagic lesions using diffusion-weighted MRI (DWI) and T2*-weighted MRI (T2*WI), respectively. RESULTS The PED group comprised 28 patients with 30 intracranial aneurysms, and the EN group comprised 24 patients with 27 intracranial aneurysms. The mean number of ischemic lesions on DWI 1 day postprocedure was higher in the PED group than in the EN group (5.2 vs 2.7, p = 0.0010). The mean number of microbleeds detected on T2*WI 6 months postprocedure was higher in the PED group than in the EN group (0.6 vs 0.15, p = 0.028). A total of 36.7% of PED-treated patients exhibited new microbleeds on T2*WI at 6 months postprocedure, with at least 77.8% of these lesions representing hemorrhagic transformations of the new ischemic lesions observed on day 1 postprocedure. The rate of adjunctive coil embolization (27.3% vs 0.0%, p = 0.016) and the mean number of ischemic lesions observed 1 day postprocedure (6.6 vs 4.3, p = 0.020) were predictors of subsequent microbleeds in the PED group. CONCLUSIONS New microbleeds detected using T2*WI at 6 months postprocedure were more common after PED treatment than after stent-mediated embolization. Approximately three-quarters of these lesions were hemorrhagic transformations of new ischemic lesions observed on day 1 postprocedure. Prevention of intraprocedural or postprocedural infarcts is necessary to reduce the risk of hemorrhagic complications following PED placement.

The results of preoperative embolization for skull base meningiomas were retrospectively evaluated to confirm the efficacy of this procedure. Skull base meningiomas that were treated with preoperative embolization were evaluated in 20 patients. The occluded arteries, embolic materials, treatment time, excision rate, neurologic manifestations, and complications were analyzed. The embolic material was 80% liquid, 30% coils, and 15% particles. The surgery was normally completed within 3 to 5 hours. Blood loss was normally approximately 250 mL, excluding four patients having the following conditions: malignant meningioma, a large tumor located on the medial side of the sphenoidal ridge, the petroclival tumor, and infiltrated tumor into the sigmoid sinus. The mean excision rate was 90%, achieving a Simpson grade III, but 10% were graded as Simpson grade IV. No permanent complications due to the preoperative embolization occurred. No neurologic symptoms occurred after excision. Current cerebral endovascular treatment is sophisticated, and the complication rate has markedly decreased. Although it was impossible to compare directly with or without operative embolization, preoperative embolization should be actively used as part of the treatment for this benign tumor, with better understanding of dangerous anastomosis.

Herein, we describe a case of traumatic direct carotid cavernous fistula (DCCF) treated with target coil embolization using the combined transarterial and transvenous balloon-assisted technique. The patient was a 59-year-old woman who had been involved in a vehicular accident. She was admitted to the hospital due to chemosis and exophthalmos. Cerebral angiography revealed a shunt from the internal carotid artery (ICA) to the cavernous sinus (CS), which indicated DCCF. Thus, target coil embolization using the combined transarterial and transvenous balloon-assisted technique was performed. Angiography was performed 1 week after surgery to confirm the disappearance of DCCF. No recurrence was observed during the 1-year follow-up after treatment. Thus, target coil embolization using the combined transarterial and transvenous balloon-assisted technique is safe and effective for the treatment of traumatic DCCF.