Ischemic complications can occur after revascularization surgery for moyamoya disease, but acute contralateral internal carotid artery (ICA) occlusion is an extremely rare complication. The patient was a 51-year-old woman with no medical history. Left frontal lobe infarction and bilateral ICA terminal stenosis were identified by repeated transient right paresis and aphasia. We diagnosed her with quasi-moyamoya disease associated with hyperthyroidism and performed revascularization surgery for the symptomatic left side. Although neurological symptoms did not worsen immediately after the surgery, disturbance of consciousness, right conjugate deviation, and left paresis appeared 4 hr after the surgery. New infarction appeared in the right frontal lobe, and the blood signal beyond the right middle cerebral artery (MCA) disappeared on MRI and MRA. Mechanical thrombectomy (MT) using a suction catheter improved antegrade blood flow in the MCA. The left paresis remained at discharge (modified Rankin Scale score = 4), but she was able to walk independently 3 months after the operation and was independent at home. Acute contralateral ICA occlusion after revascularization for moyamoya disease is an extremely rare complication, but the symptoms can be severe and treatment should be considered. To the best of our knowledge, there have been no reports of MT for postoperative acute contralateral ICA occlusion. Since the results of endovascular treatment such as percutaneous transluminal angioplasty and stent placement for patients with moyamoya disease are poor, MT using an aspiration catheter could be a good treatment option.

A thrombosed giant aneurysm of the V1 and V2 segments of the vertebral artery (VA) is rare. Therefore, there is controversy regarding its optimal treatment. A case of a symptomatic giant VA aneurysm located in the V1 to V2 segments on the left treated successfully by endovascular trapping of the VA is reported. A 68-year-old woman presented with swelling in the left anterior neck. Computed tomography angiography (CTA) showed a giant aneurysm measuring 47 × 58 × 47 mm³ in the left neck. Ten days after her first visit, she presented with sudden onset of left anterior neck pain. Repeated CTA showed a partial thrombus in the aneurysm. Angiography showed two thrombosed giant aneurysms located in the V1 to V2 segments of the left VA. After endovascular trapping for the aneurysms, the anterior neck pain resolved and the aneurysm gradually shrank. This case demonstrates that endovascular surgery is better than open surgery because it is less invasive. When performing endovascular treatment, trapping will be an alternative strategy for a symptomatic giant thrombotic aneurysm of the V1 and V2 segments of the VA if the patient can tolerate ischemia.

Carotid-cavernous sinus fistula (CCF) caused by a ruptured aneurysm of the persistent primitive trigeminal artery (PPTA) is rarely reported. A 69-year-old woman presented with progressive ptosis and pulsating tinnitus. Vertebral angiography under flow control of the internal carotid artery revealed CCF associated with a ruptured PPTA-trunk aneurysm, and PPTA was divided into Saltzman type 2. Endovascular treatment was performed by coil embolization of the aneurysm and parent artery occlusion of the PPTA, preserving the basilar artery (BA) side of PPTA, without complications. In the case of ruptured aneurysms originating from the Saltzman type 2 PPTA trunk, parent artery occlusion of the PPTA might be a treatment option and preservation of the BA side of PPTA is necessary to avoid ischemic complication of pons.

Solitary fibrous tumor (SFT) or hemangiopericytoma (HPC) is a rare fibroblastic tumor of mesenchymal origin. SFT or HPC comprises <1% of all primary central nervous system tumors. SFT or HPC of the sellar or suprasellar region is even more unusual. We herein report a sellar SFT or HPC in an octogenarian who achieved favorable progress with partial removal followed by fractionated gamma knife radiosurgery. An 87-year-old woman presented with occasional headache and visual field defects. A rapidly growing tumor of the sella turcica was diagnosed. The patient underwent endoscopic transnasal transsphenoidal surgery; however, only partial resection of the tumor was possible, as it was fibrous and hard with increased vascularity. A histological examination confirmed the tumor to be grade II SFT or HPC. Two months after the resection, the residual tumor grew rapidly. Given the patient’s advanced age, re-surgery was not the preferred option; thus, fractionated gamma knife radiosurgery (marginal dose, 30 Gy in five fractions) was performed. MRI and visual field examination performed 3 months after irradiation revealed tumor shrinkage and improvement in the visual field, respectively. One year and three months after irradiation, the tumor continued to shrink and her visual field had improved. Taking age into consideration, partial resection with fractionated gamma knife radiosurgery was the more appropriate choice for both local tumor control and the safety of the optic apparatus.

Intramedullary spinal cord tumors are rare in children. Regardless of the type of tumor, surgical removal is thought to improve progression-free survival. However, postoperative kyphosis is a serious problem in children, who can expect long-term survival. We present a pediatric case of neurofibromatosis type 2-related spinal ependymoma at the cervicothoracic regions where acute neurological deterioration was developed due to a combination of tumor recurrence and postoperative kyphotic deformity. In the first surgery, subtotal tumor resection was performed via osteoplastic laminotomy. Postoperative radiological evaluation at several months showed cervicothoracic junctional kyphosis, which subsequently made a significant improvement by lifestyle instructions. However, 22 months after the surgery, he exhibited rapid neurological deterioration caused by the regrowth of the recurrent tumor and re-emergence of kyphotic deformity, which led to the fixed laminar flap sank into the spinal canal. Therefore, a second surgery was performed 23 months after the first surgery, and gross total removal was achieved. Osteoplastic laminotomy is presumed to reduce the occurrence of postoperative kyphosis compared with laminectomy, but there have been no reports on the spinal cord compression by plunging of the re-fixed laminar flap into the spinal canal. The kyphosis deformity increases the chance of re-fixed laminar flap coming off, thereby accelerating neurological injury on top of the neural damage by tumor recurrence itself. Therefore, pediatric patients with spinal cord tumors should be carefully managed in terms of recurrent tumors and postoperative kyphosis, and timely surgical intervention is necessary before kyphotic deformity becomes evident.

Iatrogenic vertebral artery (VA) injury in cervical fusion is an extremely rare complication but can lead to serious sequelae. We present two successful cases of internal trapping for preventing delayed-onset ischemic stroke after iatrogenic VA stenosis caused by a cervical pedicle screw. A 34-year-old female underwent posterior cervical fusion for C4/C5 dislocation fracture. No neurological deficits were observed after the operation. However, the postoperative images revealed that the left C5 pedicle screw perforated the transverse foramen, and the left VA was suspected to be occluded at the screw insertion site. Before revision surgery, we tried to embolize the injured VA with coils. A microcatheter could be navigated from the ipsilateral VA to the distal of the screw, and internal trapping was performed with coils. Another case is that of a 50-year-old male with cervical spondylosis, who underwent posterior decompression and cervical fusion. The neurological symptoms did not deteriorate after the operation. However, the postoperative computed tomography images revealed the perforation of the right C3 transverse foramen by the pedicle screw. In right vertebral angiography, about 70% stenosis was observed at the screw insertion site. Although revision surgery was not planned due to good stability, we embolized the right VA after balloon occlusion test, to prevent the delayed-onset thromboembolic complications. Both the patients recovered without any neurological deficits. Iatrogenic VA injuries, even if asymptomatic immediately after surgery, can lead to serious sequelae in case of delayed-onset ischemic stroke. Therefore, careful attention should be paid when the screw perforates the transverse foramen.

The gelatin–thrombin matrix, Floseal, is an excellent novel hemostatic agent that is used in various surgical fields. Thrombin is a serine protease, and the conversion of prothrombin to thrombin is an essential step in the coagulation cascade. However, thrombin can induce blood–brain barrier (BBB) disruption and vasogenic brain edema. This report describes two cases of gelatin–thrombin matrix-related cyst formation after cerebral hematoma evacuation. An 82-year-old man with a gelatin–thrombin matrix-related cyst was treated by cyst drainage and fenestration to the lateral ventricle. Histological evaluation of the cyst wall showed a gelatin–thrombin matrix reserve, marked infiltration of inflammatory cells, and foam cell accumulation. In addition, an 85-year-old woman with a gelatin–thrombin matrix-related cyst was treated with steroids and responded well. In both cases, the post-treatment course was uneventful. Cyst shrinkage and no recurrence were observed. The gelatin–thrombin matrix can cause cyst formation with brain edema. This is the first report demonstrating the cyst wall pathology and the steroid responsivity on cyst shrinkage. The mechanism of cyst formation is thought to be thrombin-induced BBB disruption. Excess gelatin–thrombin matrix should be carefully removed from the surgical beds, particularly those having a blinded space from the neurosurgical microscope.

We report for the first time a case of choroid plexus papilloma (CPP) of the fourth ventricle associated with adrenal pheochromocytoma. A large tumor was found in the fourth ventricle of a 24-year-old man who presented with symptoms of increased intracranial pressure due to obstructive hydrocephalus. A systemic search revealed that the patient also had an asymptomatic left adrenal tumor. Both tumors were resected. The pathological diagnosis of the brain tumor was CPP and that of the adrenal tumor was pheochromocytoma, both of which showed no pathological signs of malignancy. Genetic testing for von Hippel–Lindau disease was negative. There have been no reports of cases of CPP associated with pheochromocytoma. In this report, we discuss the relationship between both tumors.

This is the first report of a carotid aneurysm that developed from a cavernous carotid artery contiguous with a prolactinoma during medical treatment of the prolactinoma, which gradually grew larger while the tumor regressed. A 78-year-old woman presented with headache and neurological symptoms indicating the involvement of cranial nerves in the cavernous sinus. Gadolinium-enhanced T1-weighted magnetic resonance imaging on admission revealed an abnormal right cavernous sinus, with an approximately 17 mm mass extending into the right cavernous portion of the internal carotid artery, and was contiguous with the intracavernous carotid artery. She was diagnosed with pituitary apoplexy due to a prolactinoma and started cabergoline treatment. After medical treatment, a carotid aneurysm emerged. The aneurysm continued to grow and reached a maximum diameter of 10.4 mm at 81 months after the initiation of treatment. The patient underwent endovascular coil embolization, following which the aneurysm regressed. Association between a prolactinoma and the development of a contiguous aneurysm remains undetermined. However, this is an odd phenomenon, and to the best of our knowledge, this is the first reported case of the development of an aneurysm that was associated with a pituitary tumor.

Saccular limited dorsal myeloschisis (LDM) is characterized by a fibroneural stalk linking the saccular skin lesion to the underlying spinal cord. Since untethering surgery during the early postnatal period is often indicated to prevent sac rupture, saccular LDM should be distinguished from myelomeningocele (MMC) during the perinatal period. We treated two patients with the spinal cord deviation from the spinal canal to the sac, which mimicked a prolapse of the neural placode into the MMC sac. In patient 1, pre- and postnatal magnetic resonance imaging (MRI) revealed that the spinal cord was strongly tethered to the thick stalk. During surgery, the dorsally bent cord and stalk were united, and the border between these two was determined with intraoperative neurophysiological mapping (IONM). In patient 2, the spinal cord was tethered to two slender stalks close to each other, which was visible with the combined use of sagittal and axial postnatal three-dimensional heavily T2-weighted imaging (3D-hT2WI). The preoperative MRI hallmark of saccular LDM is the visualization of a stalk that links the bending cord and sac. Complete untethering surgery to return the cord into the spinal canal and correct its dorsal bending is recommended.

Glioblastoma multiforme (GBM) is an aggressive cancer type, with fewer than 3–5% of patients surviving for more than 3 years. We describe a 48-year-old right-handed man who presented with generalized seizure attacks. Magnetic resonance imaging (MRI) revealed a heterogeneous gadolinium-enhancing lesion in the left inferior parietal lobule. The patient underwent awake surgery, and tumor resection included abnormalities on T2-weighted MRI, with subcortical mapping used to identify the deep functional boundaries. After supratotal resection, the tumor was diagnosed as GBM without isocitrate dehydrogenase (IDH) 1 and 2 mutations. At a follow-up evaluation, 9 years and 2 months after the surgery, the patient appeared healthy, and no relapse or recurrence was observed. We present the case of a long-term survivor of IDH-wildtype GBM. This case suggests that supratotal resection with intraoperative awake brain mapping can improve survival without impairing the patient’s neurological functions.

After revascularization surgery for patients with moyamoya disease (MMD), local and global hemodynamic changes occur intraoperatively and in the early postoperative period. Local cerebral hyperperfusion and watershed shift ischemia are well-known perioperative pathologies after revascularization for MMD, but early venous filling phenomenon is markedly rare. We report the case of a 19-year-old woman with hemorrhagic-onset MMD who presented with grand mal seizure and subarachnoid hemorrhage. She underwent superficial temporal artery (STA)–middle cerebral artery (MCA) anastomosis combined with indirect pial synangiosis on the affected hemisphere. Intraoperatively, notable early arterial blood filling in the fine cortical vein was observed around the site of anastomosis right after the STA–MCA anastomosis under the surgical microscope and fluorescence indocyanine green video angiography. Recovery of consciousness after general anesthesia was normal, although she exhibited a focal seizure 1 hour later. Postoperative magnetic resonance imaging was not remarkable, and cerebral hemodynamics significantly improved in the acute stage after surgical revascularization. Considering the intrinsic vulnerability of the microvascular anatomy of MMD, the present case is notable because early venous filling was observed intraoperatively. This phenomenon suggests the existence of a potential arteriovenous shunt as an underlying pathology of MMD, but its implications in the early postoperative course should be further verified in a larger number of MMD patients undergoing surgical revascularization.

Cavernous sinus (CS) dural arteriovenous fistula (dAVF) presents ocular symptoms and visual disorders due to retrograde drainage from the CS into the superior ophthalmic vein (SOV). Some papers reported non-CS dAVFs with those symptoms. We present a unique case of transverse-sigmoid sinus (TSS) dAVF with localizing signs of CS dAVFs resulting from congested cerebral venous outflow into the CSs and SOVs in an 86-year-old female patient. Right pulsatile tinnitus and chemosis appeared a few years ago. After experiencing progressive bilateral blurred vision and decreased visual acuity with papillary edema for a few months, she was admitted to our hospital. Cerebral angiography demonstrated right sigmoid sinus dAVF with retrograde venous reflux into the superior sagittal sinus (SSS) and contralateral TSS without cortical venous reflux. Under the influence of congestion of the SSS, cerebral venous outflow drained into the CSs subsequently into the SOVs. Trans-arterial embolization using ethylene-vinyl alcohol copolymer was conducted via the right middle meningeal artery. After treatment, right chemosis immediately improved. The 2-month follow-up examination revealed resolution of bilateral visual acuity and improvement of papillary edema. Our case demonstrates that retrograde drainage into the SOVs with not only directly arterialized shunted flow but also congested cerebral venous outflow can cause CS dAVFs-like symptoms.

We report a rare case of a basilar artery occlusion (BAO) caused by thrombosis as an initial magnification of acute myelogenous leukemia (AML) and performed mechanical thrombectomy (MT) to treat it. A 67-year-old female presented left hemiparalysis of her arm and right-sided blindness. Magnetic resonance imaging (MRI) and magnetic resonance angiography revealed acute infarction in the left occipital and anterior lobes of the cerebellum and incomplete BAO. Her blood test showed hyperleukocytosis with precursor cells and high levels of C-reactive protein, and we diagnosed AML and disseminated intravascular coagulation (DIC). We decided to treat conservatively with rapid rehydration and heparin, but three hours after admission, she suddenly lost consciousness. We performed acute MT with a direct aspiration first-pass technique (ADAPT). A white elastic embolus was aspirated, and DSA showed successful recanalization of the basilar artery. The next day, MRI revealed acute infarction in the midbrain and bilateral thalamus. The patient remained unconscious after MT and so chemotherapy to treat the acute leukemia could not be performed. The patient died of the primary disease 14 days after BAO. Thrombosis in association with AML is very rare disease and could occur in arterial vessels because of hypercoagulation, and this tendency may not respond to anticoagulation therapy. Although ADAPT might be performed safety without complications even in cases of DIC, indications for treatment with MT should be carefully considered in patients in whom hemorrhage is a possibility.

Cognitive decline is a well-known chronic side effect of multidisciplinary treatment of pineal region tumors, whereas epilepsy is an under-reported chronic consequence caused by multiple potential factors including radiotherapy, surgery, or chemotherapy. Some long-term survivors have suffered drug-resistant epilepsy after treatment, which impaired the quality of life. We report five consecutive patients with drug-resistant epilepsy after combined treatment of pineal region tumor (5 men, aged 21–42 years) among 1201 epilepsy patients who underwent comprehensive evaluation in our tertiary epilepsy center from 2011 to 2018. The comprehensive epilepsy evaluation included medical interview, long-term video electroencephalography (EEG) monitoring (VEM), and magnetic resonance (MR) imaging. The patients started to have seizures at 2–22 years after initial treatment for the tumor. Four of the five patients had focal impaired awareness seizures, whereas one patient had only visual aura. All patients had EEG seizures during VEM, which confirmed the diagnosis of focal epilepsy, but three patients had no interictal epileptiform discharges (IEDs). Two patients had diagnoses of focal epilepsy arising from the left occipital region based on ictal EEG findings. Both patients had MR imaging lesion in the left occipital lobe, radiation-induced cavernoma, or surgical injury. The remaining three patients showed poor localization of epileptogenic foci based on VEM and MR imaging. Drug-resistant epilepsy after multidisciplinary treatment of pineal region tumor is characterized by focal impaired awareness seizures with poorly localized EEG onset or rare interictal spikes.

We present a 69-year-old woman with colorectal cancer and a left frontal lobe tumor that was diagnosed as a cerebral amyloidoma after surgical resection. Further postoperative systemic evaluation revealed another amyloidoma in her hip as well as Sjögren’s syndrome. Systemic amyloidosis was not present. To the best of our knowledge, this is the first case of cerebral amyloidoma presenting as one of the multiple localized amyloidomas accompanied by Sjögren’s syndrome. We also present a systematic review of 65 cerebral amyloidoma cases reported in the literature over the past 40 years and discuss patient characteristics and pathological and imaging findings associated with prognosis.

A 60-year-old woman, who experienced progressive right visual loss, was diagnosed with an unruptured large cerebral aneurysm. Magnetic resonance imaging (MRI) and angiography revealed a large partially thrombosed anterior communicating artery (Acom) aneurysm. The aneurysmal neck was located at the junction of the left A1–A2 segments, and the aneurysmal dome communicated with the right A1–A2 junction by the Acom. Endovascular treatment using the flow alteration technique was selected. Following an oral antiplatelet therapy for 9 days, balloon test occlusion (BTO) of the medial portion of the left A1 segment was performed under local anesthesia. After confirming the tolerance of the BTO, internal trapping of the medial portion of the left A1 segment by detachable coils was performed following intra-aneurysmal coil embolization. Oral antiplatelet treatment was continued for 19 days postoperatively. Within 3 months following the operation, her right visual acuity dramatically improved to the original level. Owing to aneurysmal recanalization and the disappearance of the thrombus, the second and third embolization was performed through the Acom route, 4 months and 3 years following the first embolization, respectively, and followed up for an additional 7 years by MRI; no deterioration of her visual acuity and no aneurysmal recanalization was observed. Thus, endosaccular embolization combined with flow alteration is considered a useful alternative treatment for large and partially thrombosed Acom aneurysms.

Soft tissue calcifications are common findings in patients with various diseases, such as malignant tumors, collagen diseases, trauma, and chronic kidney disease. The majority of these lesions are not clinically significant; however, they can cause specific disorders within a limited space, such as the spinal canal. Here, we report the case of a patient undergoing fusion surgery for lumbar canal stenosis due to degenerative spondylolisthesis and multiple intraspinal canal calcifications associated with psoriatic arthritis (PsA). A 55-year-old female patient presented with pain in the left leg and intermittent claudication for 1 month. One year ago, she was diagnosed with PsA and received outpatient treatment, including biological medication, at the Division of Rheumatology, Department of Internal Medicine of our institution. She was referred to our department, and radiological examination revealed lumbar canal stenosis caused by spondylolisthesis and multiple calcifications in the lumbar spinal canal. We performed posterior lumbar interbody fusion (PLIF) with percutaneous pedicle screw fixation concomitant with removal of the calcifications. The postoperative course was uneventful, and her neurological symptoms improved. Although several prior case reports have noted intraspinal canal calcifications due to collagen disease or chronic kidney disease, calcifications associated with PsA are rare. We discuss the diagnosis of PsA and its relationship with intraspinal canal calcifications by reviewing the previous relevant literature.

Heparin-induced thrombocytopenia (HIT) is an antibody-mediated drug reaction to heparin use that causes platelet aggregation, followed by thrombocytopenia. Despite the thrombocytopenia, the main complications of HIT are thromboembolic in nature rather than hemorrhagic, and in particular, intracranial hemorrhage is rare. Herein, we describe a case of atraumatic acute subdural hematoma secondary to HIT, which was treated by platelet transfusion and surgery. A 77-year-old woman was admitted to our hospital for the treatment of severe aortic valve stenosis. Unfractionated heparin was administered during the preoperative period and during the aortic valve replacement surgery. Three days after the cardiac surgery, the patient presented with coma consistent with an acute subdural hematoma in the posterior fossa and obstructive hydrocephalus. Laboratory examination revealed a marked decrease of the platelet count to 40000/µL, and subsequent serological assay confirmed the diagnosis of HIT. The patient was treated by transfusion of platelets and fresh frozen plasma, and surgical removal of the hematoma. We started the administration of argatroban for substitution of heparin 4 days after the craniotomy. On day 13 after the neurosurgery, the patient developed cerebral infarction due to left middle cerebral artery occlusion and persistent right hemiparesis. We presented a rare case of the patient who developed acute subdural hematoma complicating HIT. Emergency craniotomy was successfully performed after administering platelet transfusions. Our experience with the present case suggests that platelet transfusions may be effective for performing emergency surgery for intracranial hemorrhage, even in patients with HIT.

An accessory middle cerebral artery (AMCA) is a variant vessel that branches from the anterior cerebral artery (ACA) and runs through the Sylvian fissure along the middle cerebral artery (MCA). We report a case of acute embolic occlusion of the AMCA that was treated with thrombectomy using direct aspiration first pass technique (ADAPT). An 88-year-old woman with a history of atrial fibrillation, loss of consciousness, and right hemiparesis was referred to our hospital. Diffusion-weighted magnetic resonance imaging (MRI) showed high signal intensity in the left frontal lobe, insular cortex, and deep white matter, and magnetic resonance angiography (MRA) demonstrated left internal carotid artery (ICA) occlusion. Mechanical thrombectomy using the ADAPT technique was performed with complete recanalization. Final angiography revealed left ACA and AMCA because of the thrombus located at the origin of the left ACA and AMCA. In the case of an acute ischemic stroke associated with AMCA, it is difficult to understand and recognize the anatomy of the vessel before thrombectomy. Therefore, the ADAPT technique, which can treat acute embolic occlusion without lesion passing, is recommended due to its safety. If there is a mismatch between the perfusion area of the occluded artery and the ischemic area or the neurological findings before thrombectomy, it is extremely important to keep in mind the presence of vessel variation in the MCA.

A 78-year-old man, who had undergone lumboperitoneal shunt (LPS) placement for idiopathic normal-pressure hydrocephalus eight years prior, presented with intermittent claudication, lower back pain, and radicular pain on the inside of the right thigh. Magnetic resonance imaging (MRI) revealed an extradural arachnoid cyst (EDAC) above the lumbar catheter of the LPS. The EDAC compressed the spinal dural sac and cauda equina toward the anterior side at level L3/4, triggering his clinical manifestations. The LPS was removed and simultaneously converted into a ventriculoperitoneal shunt (VPS), which immediately improved the neurological deficits. Postoperative MRI showed shrinkage of the cyst and restoration of the compressed cauda equina. Spinal EDAC is a rare entity resulting from arachnoid membrane herniation due to a small defect in the dura mater. This is the first report showing that symptomatic EDAC can be accompanied by the lumbar catheter of the LPS and that a mere conversion from LPS to VPS or ventriculoatrial shunt might be sufficient to shrink LPS-related EDAC without invasive lumbar surgeries.

Vertebrobasilar artery dissection is an uncommon cause of acute ischaemic stroke (AIS). Optimal endovascular management has not been established. This study aimed to share our experience with endovascular reperfusion therapy for vertebrobasilar artery occlusion due to vertebral artery dissection (VAD). We retrospectively reviewed 134 consecutive patients with AIS who received urgent endovascular reperfusion therapy between November 2017 and November 2019. Three patients diagnosed with VAD were investigated. The evaluation included mechanisms of vertebrobasilar artery occlusion due to VAD, variations in endovascular procedures, and functional outcomes. Dissections at the V3, V4 and extension of V3 to V4 segments were seen in one patient each. The mechanism of AIS was different in each patient: occlusion of the distal non-dissected artery due to an embolus from the dissection site (distal occlusion), haemodynamic collapse of the entire vertebrobasilar artery system due to the arterial dissection itself (local occlusion), or coexistence of distal occlusion and local occlusion (tandem occlusion). The endovascular reperfusion therapy was performed corresponding to the abovementioned mechanisms: mechanical thrombectomy for distal occlusion, stenting for local occlusion, and a combination of thrombectomy and stenting for tandem occlusion. In all three patients, effective recanalization and functional independence (modified Rankin Scale scores of 0–2 at 90 days after the onset) were achieved. Endovascular treatment corresponding to the individual mechanism of AIS may improve patient outcomes.

Giant pituitary adenomas carry significant surgical risks when treated with transsphenoidal approaches or the transcranial approach alone. Combined transsphenoidal and transcranial approaches have been reported; however, removing adenomas extending into the third ventricle may still be challenging. We report a case of giant pituitary adenoma expanding into the third ventricle, which was removed using a combined transventricular preforniceal approach and an endoscopic endonasal transsphenoidal surgery (ETSS). A 41-year-old man with headache, nausea, and a 1-week history of a visual field defect was transferred to our hospital. He had a disturbed left visual acuity, right homonymous hemianopia, and choked disc in both eyes. Preoperative magnetic resonance imaging revealed a giant pituitary adenoma with a maximum diameter of 55 mm extending from the intrasellar to the suprasellar region, thus occupying the entire third ventricle and causing hydrocephalus. The space between the anterior commissure and the fornix was expanded. The foramen of Monro was shifted backward due to compression by the tumor. He underwent maximum surgical resection using a combined transventricular preforniceal approach and ETSS. Considering technical demands and reliability, the intra- to suprasellar parts were removed by ETSS while the intraventricular part was removed through the preforniceal approach. The residual tumor in the right cavernous sinus and behind the anterior communicating artery was treated with stereotactic radiotherapy. One year after the operation, the patient leads an independent life. The combined technique of the preforniceal approach and ETSS provided a direct view of the entire third ventricle and hemostasis in the present case.

Prosthetic valve endocarditis (PVE) can cause large cerebral vessel occlusion. Many reports suggested that mechanical thrombectomy (MT) is effective and useful for early diagnosis from the histopathological findings of thrombus. We present the case of a 62-year-old man, with a history of prosthetic aortic valve replacement and pulmonary vein isolation for his atrial fibrillation, who developed a high fever and an acute neurological deficit, with left hemiplegia and speech disorder. He was diagnosed as having an acute right middle cerebral artery embolism and underwent an MT. The embolic source was found to be a PVE vegetation. However, histopathological analysis of the thrombus could not detect the actual diagnosis. Although he was treated for bacterial endocarditis, his blood culture revealed a rare fungal infection with Exophiala dermatitidis not until >3 weeks after admission. Subsequently, a ß-D-glucan assay also indicated elevated levels. Although he underwent an aortic valve replacement on day 36, MRI showed multiple minor embolic strokes till that day. Early diagnosis of fungal endocarditis and detection of the causative pathogen are still challenging, and the disease has a high risk of occurrence of early and repeated embolic stroke. In addition to clinical findings and pathological studies, ß-D-glucan assay might be a good tool for the diagnosis and evaluation of fungal endocarditis.

A case of ruptured anterior cerebral artery (ACA) dissection was treated with multiple neck-bridge stents, with modification of antiplatelet administration according to changes in the shape of the aneurysm in the acute phase. A 67-year-old woman presented with severe subarachnoid hemorrhage and fusiform dilatation was observed in the left ACA between the A1 and A2 segments. The use of stents in the acute phase is associated with high risk of ischemic complications. Prasugrel administration, which is considered to have low drug resistance, may have allowed safe stent use in the acute phase.

We report a case of recurrent chronic subdural hematoma (CSDH) treated using the trans-cell approach through a closed-cell stent for middle meningeal artery embolization (MMAE). A 77-year-old man with acute ischemic stroke due to anterior circulation tandem occlusion was treated with intracranial thrombectomy and carotid artery stenting using a closed-cell stent 5 years ago. He experienced head trauma after a fall, which then developed into a CSDH. Burr hole surgery was performed twice, followed by MMAE considering the high possibility of recurrence due to antiplatelet therapy and brain atrophy after ischemic stroke. A distal access catheter was inserted into the external carotid artery through the closed-cell stent, and a microcatheter was navigated in the middle meningeal artery. The anterior and posterior convexity branches were embolized with 16.7% N-butyl cyanoacrylate. The postoperative course was favorable, and CT at 3-month follow-up showed a decrease in the hematoma. Even after the placement of the closed-cell stent, endovascular treatment of the external carotid artery is possible and can be a therapeutic option using the trans-cell approach.

Double crush syndrome (DCS) is a clinical condition involving impingement of the spinal and peripheral nerves. DCS of the lower limbs has been recognized; however, no detailed reports have been published. Herein, we report a rare case of the coexistence of L5 radiculopathy and peroneal nerve entrapment neuropathy. The patient suffered from pain in the left lower leg and left foot combined with muscle weakness in the left leg without a Tinel-like sign in the peroneal tunnel area. MRI showed a deficit in the left L5 nerve root sleeve, and X-ray imaging revealed L5 spondylolysis. Lumbar fusion surgery was performed at L5-S1. Subsequently, the patient’s symptoms were partially improved, but the pain and toe and ankle motor weakness persisted. In addition, a Tinel-like sign appeared at the entrapment point of the peroneal nerve. The entrapped peroneal nerve was decompressed, and the patient’s symptoms improved. The patient had L5 radiculopathy owing to the improvement in his symptoms in the upper leg before and after lumbar surgery. It is unclear why no Tinel-like sign was detected before the first surgery, but we hypothesized that L5 nerve disorder may mask the symptoms triggered by compression of the peroneal nerve due to the complex pathology of DCS and dynamic factors. Distinguishing between radiculopathy and relative peripheral neuropathy should always be a consideration. DCS may mask characteristic symptoms, and it is important to carefully follow up the patient to detect changes in his or her condition.

In carotid artery stenting (CAS) for highly tortuous carotid stenosis, it is often difficult to guide rigid devices such as carotid stents. There are various adjunctive techniques using a guidewire: the buddy wire technique, the sheep technique, and the stiff guide technique. We report a case in which the tortuous vessel was straightened and a stent could be inserted. A 64-year-old man with amaurosis had highly tortuous left carotid stenosis. Despite the best medical treatments, he often had transient cerebral ischemic symptoms, so we planned CAS. We could insert the first stent, but the proximal vessel was kinked by the placement of the stent. It was so tortuous that the second stent could not be inserted by adjunctive techniques. Therefore, the proximal balloon was inflated and pulled back to straighten the tortuous vessel, and then we could insert the stent. We named this technique the “snake hunt technique” because it was just like catching a snake given that the tortuous vessel was stretched. This technique could be a troubleshooting step when it is difficult to insert a stiff device such as a stent or balloon even with the use of various adjunctive techniques.