We report a very rare case of intracranial capillary hemangioma. This 15-year-old girl complained of pulsating headache in the temple area that aggravated with change of body positions. This headache usually lasted for 5 min and resolved without any treatment. Preoperative computed tomography (CT) and magnetic resonance imaging (MRI) strongly suggested cavernous hemangioma in the right deep parietal lobe. She underwent complete resection of the tumor through right parietal craniotomy. Postoperative course was uneventful. Histologic examinations demonstrated a densely grown numerous capillary-like vascular structure with endothelial cells, hemosiderin deposition, and hemorrhage. Intracranial, intra-parenchymal capillary hemangioma is a very rare vascular tumor or tumor like lesions. Only four cases with intracranial, intra-parenchymal capillary hemangioma were reported previously. Differential diagnosis includes other vascular tumors such as cavernous hemangioma, but it is not so easy to differentiate capillary hemangioma from other lesions. Therefore, surgical excision and histologic diagnosis would be important to diagnose it if possible.

Intracranial mesenchymal chondrosarcoma (MCS) is a rare neoplasm. The diagnosis of MCS is confirmed by the presence of a biphasic pattern on histological examination, comprising undifferentiated small round cells admixed with islands of well-differentiated hyaline cartilage; however, a differential diagnosis may be challenging in some cases. A 28-year-old woman with a 2-month history of headache was referred to our hospital. Radiologic studies showed an extra-axial lobulated mass composed of calcified and uncalcified areas occupying the left middle fossa. Surgical resection was planned, but her headache suddenly worsened before her planned hospital admission and she was admitted as an emergency. Radiologic studies showed an acute hemorrhage in the uncalcified part of the mass. The mass was resected via the left zygomatic approach after embolization of the feeder vessels. The most likely histopathological diagnosis was MCS. However, the typical bimorphic pattern was not identified in our surgical samples; each undifferentiated area and well-differentiated area was observed separately in different tissue specimens, and no islands of well-differentiated hyaline cartilage were identified within the undifferentiated areas in the same specimen. Molecular assays confirmed the presence of HEY1-NCOA2 fusion. IRF2BP2-CDX1 fusion and IDH1/2 mutations were negative. The final diagnosis of MCS was made based on the presence of HEY1-NCOA2 gene fusion. MCS should be included in the differential diagnosis when radiologic studies show an extra-axial lobulated mass with calcification. Furthermore, molecular demonstration of HEY1-NCOA2 gene fusion may help make a precise diagnosis of MCS, especially in surgical samples lacking the typical histopathological features.

A 68-year-old female was admitted to our hospital with right-sided hemianopsia. Magnetic resonance imaging (MRI) demonstrated a well-enhanced tuberculum sellae region tumor. The patient underwent surgical tumor resection via an extended endoscopic endonasal trans-sphenoidal approach and the tumor was totally removed. The mass was extremely soft and there was no clear attachment between it and the dura mater. Furthermore, the histopathological findings obtained for the tumor during intra-operative rapid diagnosis were divergent from typical meningioma. We therefore diagnosed the tumor intra-operatively as a pituitary adenoma. However, the post-operative pathological diagnosis for the tumor was chordoid meningioma (CM). CM is a rare subtype of meningioma, and most of such tumors arise in the convexity. In the preoperative MRI in the present case, meningioma was suspected; however, since we did not consider CM for differential diagnosis, we failed to reach an accurate diagnosis during the operation. Tuberculum sellae CM is very rare, and only a few cases have been reported previously. The surgical strategy will differ greatly depending on whether the tumor is a meningioma or a pituitary adenoma, especially when treatment involves the dura mater. The pre and/or intra-operative diagnosis is thus very important for developing an accurate treatment strategy. We report here the details of our rare case and describe the intra-operative features of tuberculum sellae CM.

Middle meningeal arteriovenous fistula (MMAVF) of a non-fractured site is extremely rare, and the clinical characteristics are still unclear. We report a case of delayed onset of venous infarction due to an MMAVF following a fall accident. A 69-year-old man sustained multiple trauma due to a fall accident. Head computed tomography (CT) showed traumatic subarachnoid hemorrhage, a left subdural hematoma, and skull fracture in his right temporal bone, all of which were managed conservatively. Five days after his admission, he suddenly exhibited total aphasia and right hemiparesis. Emergent CT revealed sporadic low-density areas in his left cerebral hemisphere, and four-dimensional CT angiography (4D-CTA) showed dilatation of the left middle meningeal artery and early venous drainage in the cavernous sinus and anterior temporal diploic vein (ATDV). A series of hemodynamics of 4D-CTA revealed early venous filling of ATDV interrelated with retrograde upward flow to high convexity in the venous phase. The MMAVF was successfully obliterated by transarterial coil embolization. We herein describe this case of MMAVF in which 4D-CTA was useful for the diagnosis.

Intracranial chondroma is a rare benign tumor comprising only 0.2% of all intracranial tumors. A 27-year-old woman presented with visual dysfunction and headache. Brain computed tomography and magnetic resonance imaging revealed a suprasellar mass lesion with a calcified component. Gross total removal was achieved via a basal interhemispheric approach. Postoperatively, visual function improved to the normal range, and no recurrence was evident 4 years later. Histopathological examination confirmed the diagnosis of benign chondroma. Preoperative differentiation of chondromas from chordomas is clinically important, because of the different treatment and prognostic implications. The only effective treatment for chondroma is total surgical removal. We present a case of gross total resection of a suprasellar chondroma with reference to the literature.

Iatrogenic pseudoaneurysm formation at the deep temporal artery (DTA) is a rare complication after neurosurgical intervention by craniotomy, and its management strategy has yet to be determined. We report a patient who developed iatrogenic pseudoaneurysm at the DTA after fronto-temporal craniotomy manifesting as repeated subcutaneous hemorrhage. A 44-year-old man underwent standard fronto-temporal craniotomy for the microsurgical clipping of a ruptured anterior communicating artery aneurysm in the acute stage. The initial postoperative course was uneventful, but he developed a massive subcutaneous hematoma that penetrated the surgical wound, leading to hypovolemic shock 23 days after the aneurysm surgery. Due to the continuous hemorrhage after temporary hemostasis by ligation of the superficial temporal artery, he underwent catheter angiography, which revealed a newly-formed pseudoaneurysm at the DTA that was 16 mm in diameter. Neuroendovascular obliteration of the pseudoaneurysm was successfully performed using liquid embolization material, n-butyl-2-cyanoacrylate, under local anesthesia. Pseudoaneurysm at the DTA is a rare but possible complication after fronto-temporal craniotomy, which can be fatal due to marked hemorrhage. Due to the anatomically deep location of the DTA under the temporal muscle, we recommend accurate diagnosis of the pseudoaneurysm by catheter angiography and prompt obliteration of the affected vessel by a neuroendovascular procedure under local anesthesia, especially when the hemodynamic status is unstable.

Mechanical thrombectomy has been proposed to expand the treatment time window and enhance revascularization. However, it is unclear whether its use can be extended to patients with occlusions in acute aortic dissection, especially the thoracic aorta. A 55-year-old man underwent graft replacement for acute aortic dissection type A. On postoperative day 2, he developed stroke and computed tomography showed occlusion of the right middle cerebral artery. Mechanical thrombectomy was performed by transbrachial approach. Although successful recanalization was achieved, he suffered hemorrhagic stroke. Since there is no other effective treatment and the neurologic outcome with conservative management is poor, we consider mechanical thrombectomy to be a viable therapeutic option for the treatment of postoperative stroke in patients with acute aortic dissection type A. However, further study is warranted regarding the safety of this technique.

The diagnosis and treatment of patients with ruptured basilar artery dissection (rBAD) are often difficult. We present a case of rBAD diagnosed with magnetic resonance vessel wall imaging (MR-VWI) and treated with coil embolization with overlapping low-profile visualized intraluminal support (LVIS) stents. The case is of a 49-year-old woman with subarachnoid hemorrhage. digital subtraction angiography (DSA) showed irregularity in an anterior wall of the middle portion of the basilar artery, indicating the presence of a false lumen. MR-VWI showed local enhancement in an arterial wall, which was consistent with the wall irregularity observed in DSA. Overlapping stents (two LVIS stents) was performed in the basilar artery and coils were placed in the false lumen. The false lumen was completely thrombosed, and anterograde blood flow of the basilar artery was preserved. Dual antiplatelet therapy was administered, and the patient underwent an uneventful postoperative course. DSA performed 6 months later showed a white-collar sign. MR-VWI has attracted attention as a useful modality for detecting a ruptured lesion in patients with subarachnoid hemorrhage. This is the first report, to the best of our knowledge, describing the practical use of MR-VWI for rBAD. MR-VWI is suggested to improve diagnostic accuracy for rBAD. There are no established treatments for rBAD; reconstructive endovascular treatments comprising stent placement and coil embolization of a false lumen are promising. The LVIS stent has a braided design and high metal coverage ratio and is considered to be reasonable for use in rBAD. Coil embolization of a false lumen with overlapping LVIS stents may be effective for rBAD.