Triplicated middle cerebral arteries (duplicated and ipsilateral accessory) associated with triplicated anterior cerebral arteries (accessory) diagnosed by magnetic resonance angiography.

PURPOSE: To describe a case of duplicated middle cerebral artery (MCA) combined with ipsilateral accessory MCA, forming a triplicated MCA, associated with the accessory anterior cerebral artery (ACA), forming a triplicated A2 segment of the ACA detected incidentally on magnetic resonance (MR) angiography. METHODS: A 70-year-old woman with internal carotid artery (ICA) stenosis at the origin, which was detected by ultrasound, underwent cranial MR imaging and MR angiography of the intracranial region for an evaluation of brain and cerebral arterial lesions. The MR machine was a 3-Tesla scanner. MR angiography was performed using a standard 3-dimensional time-of-flight technique. RESULTS: Multiple ischemic white matter lesions are observed. No significant stenotic lesions were observed in intracranial arteries. The right duplicated MCA was originated from right distal ICA. And main MCA was originated from right ICA bifurcation. Right accessory MCA was arisen from the A2 segment of the right ACA. Thus, the right MCA was triplicated. There was also an accessory ACA forming a triplicated ACA at its A2 segment. These findings were clearly identified on partial volume-rendering (VR) images. CONCLUSION: We herein report a case of triplicated MCA associated with triplicated ACA. MCA variations are relatively rare, and this is the third case of triplicated MCA reported in relevant English-language literature. To identify multiple cerebral arterial variations, creating partial VR images using MR angiographic source images is useful.

Two Cases of Mechanical Thrombectomy in Patients with Fenestration of the M1 Segment of the Middle Cerebral Artery.

M1 fenestration of the middle cerebral artery is rare. We present two patterns of acute thromboembolic conditions in M1 fenestrations treated with mechanical thrombectomy. Case 1 was a male in his 60s presenting with right hemiparesis and aphasia. Angiography showed acute left M1 proximal occlusion; the first direct aspiration revealed two parallel routes, and the second aspiration achieved complete recanalization of the left M1 fenestration. Case 2 was a male in his 70s presenting right hemiparesis and aphasia. Angiography revealed a sudden stair-like narrowing of the left M1 in the intermediate part, and a retrograde blood flow cavity was observed on the upper side of the distal part. Mechanical thrombectomy was performed to diagnose the upper limb occlusion of the left M1 fenestration, and successful recanalization was achieved through direct aspiration. Anatomical variations, such as fenestration, should be considered to reduce complication risks.

Posterior cerebral artery (PCA)-accessory PCA (hyperplastic anterior choroidal artery) anastomosis detected on magnetic resonance angiography.

PURPOSE: To describe a case of posterior cerebral artery (PCA)-accessory PCA (hyperplastic anterior choroidal artery) anastomosis detected on magnetic resonance angiography. METHODS: A 76-year-old man with a history of cerebral infarction underwent cranial magnetic resonance (MR) imaging and MR angiography of the intracranial region for the evaluation of brain and vascular lesions. The MR machine was a 3-Tesla scanner. MR angiography was performed using a standard three-dimensional time-of-flight technique. RESULTS: There were two right PCAs. The parieto-occipital and calcarine arteries of the right PCA arose from the right ICA, indicative of accessory PCA, and there were three stenotic lesions at the proximal segment of this artery. The temporal artery of the right PCA originated from the basilar artery. A small anastomotic channel between these two arteries was identified on partial maximum intensity projection (MIP) images. Computed tomography angiography was additionally performed and the findings were confirmed. CONCLUSION: We speculated that the pressure gradient between the PCA and the accessory PCA enlarged the anastomotic channel. Partial MIP images are useful for diagnosing small arterial variations using MR angiography.

Aqueductal developmental venous anomaly causing obstructive hydrocephalus: A case report and review of the literature.

A developmental venous anomaly (DVA) is a venous drainage of the associated parenchyma that is normally asymptomatic. However, a DVA located adjacent to the aqueduct can cause obstructive hydrocephalus by blocking the flow of cerebrospinal fluid. We describe a rare case of obstructive hydrocephalus due to aqueductal stenosis secondary to a DVA. A 43-year-old man presented with sudden bilateral temporal pain during weight training. Using a 3-Tesla scanner, cranial magnetic resonance imaging (MRI) was performed, and hydrocephalus was found with mild enlargement of the lateral and third ventricles. Susceptibility-weighted imaging and postcontrast MRI revealed that the DVA from the bilateral thalami narrowed the orifice of the aqueduct on its drainage route towards the vein of Galen. We assumed that force exerted during weight training may have caused dilation of the anomalous veins, leading to his symptom. A review of the relevant English-language literature yielded only 19 cases of aqueductal stenosis due to DVA. In comparison to these cases, the duration of symptom in our case was extremely short because the patient had a history of ventriculomegaly detected on plain computed tomography and was diagnosed quickly based on the characteristic finding of DVA: the caput medusae appearance.

Type 2 left proatlantal artery with normal left vertebral artery and association with an aberrant right subclavian artery and a bi-carotid trunk.

Type 2 proatlantal artery (PA) is a rare type of the carotid-vertebrobasilar anastomosis that arises from the external carotid artery and enters the posterior fossa via the foramen magnum (FM). The type 2 PA is usually large and takes a similar course to the occipital artery (OA). The peripheral branch of the OA arises from the distal segment, just proximal to the FM. The ipsilateral vertebral artery (VA) is usually aplastic or hypo-plastic. We diagnosed a case of relatively small type 2 left PA in a patient with a normally developed ipsilateral VA. Furthermore, the patient had an aberrant right subclavian artery associated with a bi-carotid trunk. The combination of these extracranial arterial variations has not been reported in the relevant English language literature.

Right vertebral artery arising from the right common carotid artery without association with an aberrant right subclavian artery and entering the C3 transverse foramen.

The right vertebral artery (VA) rarely arises from the right common carotid artery (CCA); however, the majority of anomalous right VAs are seen in combination with an aberrant right subclavian artery (SA). Independent (or isolated) right VA of the right CCA origin is extremely rare, with only a few cases reported previously. We herein report an additional case diagnosed incidentally using computed tomography angiography. This patient had a left VA arising from the aortic arch between the origins of the left CCA and left SA. The bilateral VAs took an anterior course and entered the C3 transverse foramina, at an extremely high level.

Endovascular Treatment for Acute Ischaemic Stroke Caused by Vertebral Artery Dissection: A Report of Three Cases and Literature Review.

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.

A Case of Neurosarcoidosis-Induced Syndrome of Inappropriate Secretion of Antidiuretic Hormone Diagnosed with Neuroendoscopy.

We treated a patient with neurosarcoidosis, which caused the syndrome of inappropriate secretion of antidiuretic hormone (SIADH), in whom diagnosis was performed using neuroendoscopy. The patient was a 56-year-old female who was hospitalized for hyponatremia and diagnosed with SIADH based on a detailed examination. During the course, she developed impaired consciousness due to acute hydrocephalus, which improved after ventricular drainage. Head magnetic resonance imaging (MRI) confirmed nodular lesions at the floor of the third ventricle and the cerebral aqueduct. Neuroendoscopic biopsy led to the diagnosis of neurosarcoidosis. Her hyponatremia improved after steroid therapy. Neurosarcoidosis can cause SIADH, and complication of hydrocephalus may lead to a poor prognosis. Neuroendoscopy appears to be effective for the diagnosis of neurosarcoidosis with hydrocephalus and helps in deciding the treatment modality.

Neurocysticercosis in Japan.

Neurocysticercosis is a condition rarely reported in Japan, and therefore, the specific route of infestation in our set up has not been conclusively elucidated. Preoperative diagnosis remains difficult to make with certainty due to the slowly evolving nature of the disease and the fact that there are no typical characteristic clinical findings particularly associated with the disease. The hematological, serological, serum biochemistry, stool, and radiological tests were nonspecific for neurocysticercosis. The characteristic neuro-imaging findings were demonstrated in this case, and histopathology confirmed Taenia solium parenchymal infestation.

Odontoid compression of the brainstem without basilar impression-- "odontoid invagination".

We report five patients with odontoid invagination, in which the odontoid process bulges upward into the foramen magnum and compresses the brainstem without deformity of the occipital bone. Two patients had a craniovertebral abnormality associated with Chiari malformation without instability of the craniovertebral junction (stable odontoid invagination). The other three patients had dislocation of the craniovertebral junction due to iatrogenic destruction of the occipital condyle, rheumatoid arthritis or an anomaly of C2 (unstable odontoid invagination). Patients with stable odontoid invagination underwent a transoral odontoidectomy followed by occipitocervical fixation. Those with unstable odontoid invagination underwent cervical traction followed by posterior fixation in reducible cases, while in irreducible cases odontoidectomy with subsequent occipitocervical fixation was performed. Decompression of the neuraxis together with symptomatic improvement was achieved in all patients and none became unstable or developed new symptoms during follow-up ranging from 3 to 15 years.

Surgical experience with resection en bloc of intramedullary astrocytomas and ependymomas in the cervical and cervicothoracic region.

We performed 8 operations on 7 patients with benign intramedullary astrocytomas and ependymomas in the cervical and cervicothoracic region. All patients initially underwent gross total tumor resection en bloc. One patient with an astrocytoma showed tumor recurrence postoperatively, and underwent a second operation resulting in subtotal removal. The follow-up after the initial surgery ranged from 2.7 to 19.7 years (mean 8.5 years). Symptomatic improvement was observed in 6 patients after the initial operation. Two patients showed postoperative neurological deterioration, one with an ependymoma and the other after the second operation. No operative complications or deaths, nor postoperative respiratory dysfunction occurred. Benign intramedullary astrocytomas and ependymomas of the cervical and cervicothoracic spinal cord can be treated by radical resection en bloc with a low morbidity and recurrence, as well as acceptable outcomes. We describe here the surgical technique for en bloc tumor removal.

Repeat operations in the management of clival chordomas: palliative surgery.

Some chordomas have a very poor prognosis because of their aggressive growth nature, but the efficacy of repeat operations for these cases has not been well documented. This report concerns 3 patients with aggressive chordoma of the clivus, who underwent operations 6 to 12 times over a period of 8 to 17 years because of symptomatic regrowth. Overall mean interval between repeat operations was 18 months with a range from 5 to 57 months and survival times were 9 to19 years after the first surgery. Main symptoms before each operation were diplopia and visual disturbance. Repeat palliative operations by intentional extradural debulking of the tumour to decompress offending neural structures, as well as maximal removal of the tumour, using appropriate skull base approaches, can mitigate progressive symptoms, and may result in better quality and some prolongation of life, although our patients gradually deteriorated neurologically throughout the clinical course.

Simple cervical spine traction using a halo vest apparatus: technical note.

BACKGROUND: A halo vest apparatus, commonly used for external immobilization and protection of the cervical spine, offers several advantages. We present here a simple, accurate, easy, and safe cervical traction technique using a halo vest apparatus. METHODS: The distinguishing feature of our technique is that, after application of a halo vest apparatus, the halo crown is distracted gradually and stepwise by turning the bilateral screw bolts that hold the halo crown over a period of one to several weeks. After each of these steps, care must be taken to check neurologic, radiologic, and skin conditions, as well as cranial pin tightening. CONCLUSIONS: This distance control technique can provide a strong and accurate traction force by simply turning the bolts without the risk of overdistraction or the need for bed rest, and can be used in conjunction with radiologic examination and transportation of patients, even those unable to walk. The Sugita head fixation system constitutes a safe and easy way to facilitate surgical management after correction of cervical dislocation.