Subarachnoid Hemorrhage Caused by Ruptured Aneurysm of the Artery of Adamkiewicz: a Case Report.

A 66-year-old man presented with a 6-day history of progressive posterior cervical pain that included lower back pain and fever. Neurological examinations revealed neck stiffness. Computed tomography demonstrated convexity subarachnoid hemorrhage. A spinal T2-weighted image revealed a hypointense signal lesion with contrast enhancement of the intradural extramedullary space at Th12-L1. Digital subtraction angiography showed a fusiform aneurysm with a 10 mm diameter in the artery of Adamkiewicz. We diagnosed the patient's condition as a ruptured aneurysm of the artery of Adamkiewicz. By day 41 the aneurysm had disappeared following conservative treatment. Aneurysms arising from the artery of Adamkiewicz are extremely rare and can cause both convexity and spinal subarachnoid hemorrhages. Clinicians should therefore look for spinal lesions if patients with convexity subarachnoid hemorrhage of an unknown origin have lower back pain as their initial symptom.

[Temporal Profiles of Neuroimaging Features of Non-haemorrhagic and Non-ischemic Vertebral Artery Dissections for Conservative Treatment].

Most patients with non-hemorrhagic and non-ischemic vertebral artery dissections(VADs)are likely to recover with good outcomes. In contrast, some cases of uneventful outcomes have also been reported. Therefore, whether surgical treatment or prolonged follow-up should be utilized for each case remains controversial. In this study, we retrospectively investigated the radiological features and changes in non-hemorrhagic and non-ischemic VADs during the follow-up period. We reviewed the medical records of 15 consecutive patients with VADs without hemorrhage or ischemic lesions diagnosed between 2008 and 2017; all patients reported severe occipital headache. All hemorrhagic and ischemic lesions were categorized into morphological types according to the initial radiological findings. The following morphological types of dissections were observed: six cases, pearl and string type; six cases, dilatation type; two cases, stenosis type; and one case, occlusion type. We observed morphological aggravation in four cases, and among them, three underwent surgical interventions. Seven patients recovered during the follow-up period, and five of them showed marked radiological changes within 2 months. One patient died fromethe clinical onset. Therefore, careful follow-up radiological imaging is presumably necessary for patients with non-hemorrhagic and non-ischemic VADs, within at least 2 months of the clinical onset because of the tendency of VADs for rapid morphological changes during that period.

A study of prognostic factors in 45 cases of atypical meningioma.

BACKGROUND: Atypical meningioma differs from Grade I meningioma in terms of high recurrence rate and short life expectancy. We evaluated the clinical course of atypical meningioma and investigated prognostic factors affecting its outcomes. METHOD: We reviewed 45 patients with atypical meningioma who underwent surgical intervention between January 2000 and December 2013. The mean age of the patients and mean follow-up period was 58.7 years and 81.0 months, respectively. Analyses included factors such as patient age, gender, location and size of tumor, extent of surgical resection (Simpson Grading System), and MIB-1 labeling index (LI). Univariate analysis was used to detect prognostic factors associated with recurrence and survival. RESULTS: The 5-year recurrence-free rate for all 45 patients was 58.4 %; 5- and 10-year survival rates were 83.2 % and 79.9 %, respectively. In univariate analyses, age >60 years, and MIB-1 LI correlated with disease recurrence, whereas age >60 years, subtotal surgical resection, MIB-1 LI, and indication for radiotherapy correlated with death. MIB-1 LI levels higher than 12.8 % and 19.7 % predicted recurrence and death, respectively. In our cohort, 26 patients received postoperative radiotherapy including conventional radiation (n = 21) or gamma knife radiosurgery (n = 5). Postoperative radiotherapy did not decrease recurrence rates in our cohort (p = 0.63). Six and two patients who died during the study period underwent conventional radiation and radiosurgery, respectively. CONCLUSIONS: Age, male gender, extent of surgical resection, and higher MIB-1 LI influenced the outcome of atypical meningioma. In our cohort, postoperative radiotherapy failed to provide long-term tumor control. Following incomplete surgical resection of atypical meningioma in elderly patients, adjuvant postoperative radiotherapy may not be an ideal treatment option, particularly when MIB-1 LI is higher than 19.7 %.

[Perforating Artery Injury during Microsurgery for Internal Carotid Artery Bifurcation Aneurysms].

Internal carotid artery bifurcation aneurysms(ICB-ANs)are relatively rare and are difficult to occlude by direct clipping without perforating artery injury(PAI). We retrospectively analyzed 11 aneurysms in 10 cases. PAI was identified in 5 of 10 cases on postoperative computed tomography(CT)or magnetic resonance imaging(MRI), and 2 of these patients were symptomatic. PAIs were distributed in the caudate nucleus and/or the genu of the internal capsule. PAI occurred in 3 of 5 cases in which indocyanine green videoangiography(ICG-VAG)was performed. ICG-VAG is a helpful tool visualizing blood flow of vessels in surgical fields. However, PAI is a potential risk in direct clipping of ICB-ANs even if adjacent perforating arteries were observed using ICG-VAG.

Usefulness of Transcranial Motor Evoked Potential in Clipping Surgery for Cerebral Aneurysms-Introduction of a New Protocol for Stable Monitoring.

The usefulness of transcranial motor evoked potentials (Tc-MEPs) in clipping surgery has been reported. However, numerous false positive and false negative cases were reported. We report the usefulness of a new protocol compared with direct cortical MEP (Dc-MEP).Materials were 351 patients who underwent aneurysmal clipping under simultaneous monitoring of Tc- and Dc-MEPs. A total of 337 patients without hemiparesis and 14 with hemiparesis were separately analyzed. Intraoperative changes of Tc-MEP thresholds were examined in the first 50 patients without hemiparesis. The stimulation strength of Tc-MEP was set at +20% of the stimulation threshold. As thresholds changed intraoperatively, thresholds were examined every 10 min and changed stimulation strength.Stimulation thresholds of Tc-MEP were significantly decreased after craniotomy and significantly increased after CSF aspiration. The recording ratios of Tc- and Dc-MEPs were 98.8% and 90.5%, respectively. Out of 304 patients without MEP change, 5 patients developed transient or mild hemiparesis with infarction of the territory of the perforating artery arising from the posterior communicating artery. Out of 31 patients whose MEP transiently disappeared, 3 patients developed transient or mild hemiparesis. The other two patients without MEP recovery manifested persistent hemiparesis. In 14 patients with preoperative hemiparesis, 3 patients whose healthy/affected ratio of Tc-MEP was large developed severe persistent hemiparesis.We clarified the intraoperative changes of Tc-MEP thresholds for the first time. A new protocol of Tc-MEP that followed thresholds and changed stimulation strength to +20% of thresholds is useful for stable monitoring. The usefulness of Tc-MEP is the same as that or better than that of Dc-MEP.

An analysis of flow dynamics in cerebral cavernous malformation and orbital cavernous angioma using indocyanine green videoangiography.

BACKGROUND: Cerebral cavernous malformations (CCMs) are known to be vascular anomalies with low perfusion because of being angiographically occult. We attempted direct visualization of blood flow within CCMs and orbital cavernous angiomas (CAs), and analyzed flow dynamics using indocyanine green videoangiography (ICG-VAG). METHODS: This series included seven CCMs and two orbital CAs. ICG-VAG was performed to visualize blood flow of the lesions before resection. Time to peak of staining was evaluated by reviewing recorded ICG-VAG. RESULTS: In five of seven CCMs, stain was identified. CCMs were seen as avascular areas in both arterial and venous phases, and were stained gradually. Stain was maximized late after venous phase. The orbital CAs were also stained lately, but more intensely than CCMs. CONCLUSIONS: The present study directly demonstrated slow and low perfusion within CCM and orbital CA using ICG-VAG. On the basis of characteristic flow dynamics of CCMs, intraoperative ICG-VAG provides useful information in microsurgical resection.

Development of intratumoral cyst or extratumoral arachnoid cyst in intracranial schwannomas following gamma knife radiosurgery.

PURPOSE: Intracranial schwannomas presenting with cyst formation following gamma knife radiosurgery (GKRS) were investigated to clarify their clinicopathological characteristics. METHODS: Between 1994 and 2006, 492 patients presenting with intracranial schwannomas underwent GKRS. Among them, seven cases demonstrated either new formation of cysts or enlargement of preexisting cysts, which were treated with microsurgical intervention. These cases were retrospectively reviewed with regard to neuroradiological findings and histopathology. RESULTS: These seven cases included five vestibular and two trigeminal schwannomas. Preexisting cysts were enlarged following GKRS in three cases, while they were newly formed in four cases. Salvage microsurgery was carried out at 7-167 months after the GKRS, and subtotal resection was achieved in three, partial resection with or without cyst fenestration in four. Neurological symptoms were improved in all six symptomatic cases. Preoperative MRI demonstrated two characteristic types of cyst. One was the intratumoral type, indicating hemorrhagic change on the MRI. Histopathological analysis demonstrated a cavernous angioma within the solid compartment of tumor. These two cases demonstrated enlargement of residual tumor with new cyst formation after resection of only the cyst. The other type was extratumoral cyst, which had a structure with a thin cyst wall without contrast enhancement, and the cyst was composed of arachnoid cells without tumor cells. Extratumoral cysts enlarged despite effective control of the tumor itself, which may be caused by osmotic gradient induced by tumor degeneration following GKRS. CONCLUSIONS: There were two types of cysts, intratumoral cyst and extratumoral arachnoid cyst, which developed following GKRS in intracranial schwannomas. Resection of the solid compartment as well as the cyst is required in schwannomas with expanding intratumoral cyst. Conversely, fenestration of the cyst alone might be effective in extratumoral arachnoid cysts.

[A case of late-onset aqueductal membranous occlusion and a successful treatment with neuro-endoscopic surgery].

A 57 year-old man developed broad-based unsteady gait and memory loss over a period of one year. On admission, bradykinesia and impairment of postural reflex were evident. Mini-mental state examination scored 27/ 30. Urinary control was normal. MRI revealed symmetric dilatation of lateral and 3rd ventricles, but the 4th ventricle appeared normal. Partial obstruction of the aqueduct with a membranous structure was disclosed by fast imaging employing steady state acquisition (FIESTA), and the diagnosis of late-onset aqueductal membranous occlusion (LAMO) was made. The symptoms were ameliorated shortly after endoscopic aqueductoplasty (EAP) and endoscopic third ventriculostomy (ETV). Membranous occlusion of the aqueduct can be detected by FIESTA and it can be cured by neuro-endoscopic measures.

Acute ischemic complications after therapeutic parent artery occlusion with revascularization for complex internal carotid artery aneurysms.

BACKGROUND: Parent artery occlusion (PAO) is an alternative surgical strategy for complex internal carotid artery (ICA) aneurysms, which are unclippable because of their anatomical structures, including a broad neck, fragile dome, critical branch, and cavernous sinus location. Despite revascularization, ischemic complications occur after the PAO because of several factors, such as hypoperfusion, embolism, and perforator impairment. METHODS: Acute ischemic complications and their mechanisms were analyzed in a consecutive series of 32 patients presenting with complex ICA aneurysms treated by PAO. RESULTS: Fourteen ruptured and 18 unruptured aneurysms were located in the cavernous sinus (n = 16) and paraclinoid portion (n = 16). Preoperative balloon test occlusion was performed to investigate ischemic tolerance and to select the bypass method in 24 cases. An extracranial-intracranial bypass was constructed using the superficial temporal artery in 17, and a saphenous vein graft was done in 12 cases. Although postoperative hypoperfusion was prevented by revascularization based on the balloon test occlusion, acute ischemic complications due to perforator occlusion and thromboembolism were observed in 10 cases after the surgery. Five cases presented with impairment of perforating branches adjacent to the occluded parent artery, resulting in prolonged neurologic deterioration. CONCLUSION: The distal location of ICA aneurysms is a risk factor for the perforator impairment, when treated by PAO, and PAO by clip placement is preferred to endovascular coiling to prevent of perforator impairment.

[Neuroendoscopic management of a colloid cyst at the third ventricle using the high-definition flexible neuroendoscopic system: report of two cases].

Colloid cysts are benign intracranial lesions located at the anterior roof of the third ventricle, which can result in the obstruction of the foramen of Monro and subsequent hydrocephalus or sudden death. Colloid cysts have been treated by microsurgical resection or by stereotactic aspiration. More recently, the use of rigid neuroendoscopy for colloid cysts has been attempted, but the efficacy of the flexible neuroendoscopic system is undetermined except for limited reports. A 40-year-old man and a 52-year-old man were presented with obstructive hydrocephalus owing to colloid cysts in the third ventricle, who were diagnosed by the typical findings of pre-operative CT scan and MRI. In the first case, endoscopic resection of the cyst was attempted using a high-definition flexible neuroendoscopic system with a CCD camera at the tip of the endoscope. The procedure relieved his symptoms. Hydrocephalus was improved after surgery, and postoperative MRI revealed the disappearance of the third ventricle lesion. Histological examination confirmed the diagnosis of colloid cyst. In the second case, endoscopic removal of the cyst wall and the evacuation of the cyst content were attempted using a high-definition flexible endoscopic system which resulted in the improvement of hydrocephalus and marked shrinkage of the third ventricle lesion observed in postoperative MRI. There was no recurrence in either patient. We recommend endoscopic treatment for colloid cysts using the high-definition neuroendoscopic system, which enables safe and thorough manipulation of the lesion and surrounding structures.

[C2 neurinoma with intracranial extension: a case report].

We report a rare case presenting with a C2 neurinoma, which extended beyond the foramen magnum, producing a huge mass at the clivus. A 10-year-old boy with medical history of glycogenosis type VIII and attention-deficit hyperactivity disorder had been suffering from progressing foramen magnum syndrome for 36 months. MRI demonstrated a huge tumor, 70 mm in a diameter, which distributed in both the intra- and extra-spinal canal at the C2 level and extended into the intracranial space beyond the foramen magnum. The tumor was totally removed via the trascondylar fossa approach with C1 hemilaminectomy. Operative findings indicated that the tumor arising from extradural C2 nerve intruded into the intradural space, and extended beyond the foramen magnum. Foramen magnum tumors sometimes remain unrecognized until severe neurological deficits develop because of bizarre symptomatology. Surgical strategies with less invasiveness based on early diagnosis lead to successful recovery of neurological function.

Cranial hemophilic pseudotumor associated with factor IX deficiency: case report.

BACKGROUND: Hemophilic pseudotumor is an unusual complication occurring in only 1% to 2% of patients with severe factor VIII or IX deficiency, and manifests as a progressive enlargement of hematoma by recurrent hemorrhage, often resulting in bone destruction or resorption due to the chronic pressure of osseous hemorrhage. Cranial hemophilic pseudotumors are extremely rare, with only 4 previous cases associated with mild or moderate factor XIII deficiency. CASE DESCRIPTION: A 24-year-old man with moderate deficiency of factor IX developed a cranial pseudotumor as a swelling in the frontal scalp. Blood coagulation profile revealed extended activated partial thromboplastin time (58.2 seconds). Factor IX analysis showed 3% of normal activity. Computed tomography and magnetic resonance imaging demonstrated an extra-axial lesion with bone destruction, enhanced rim, and signal changes consistent with chronic hemorrhage. Surgical removal was performed. Histologic examination disclosed old blood coagulum. CONCLUSIONS: This case of cranial hemophilic pseudotumor in a patient with moderate factor IX deficiency suggests that cranial pseudotumor should be considered in the differential diagnosis of cranial lesion in a patient with hemophilia, and adequate replacement therapy in the perioperative period is essential to achieve safe surgical removal.

Sinus thrombosis in idiopathic hypereosinophilic syndrome causing fatal cerebral haemorrhage.

Idiopathic hypereosinophilic syndrome (HES) is a leukoproliferative disorder that is characterized by sustained overproduction of eosinophils and a trend towards damage to specific organs, usually the cardiovascular system. We report the case of a 76-year-old woman who was affected by idiopathic HES, which had an unusual and rapidly fatal course. Sinus thrombosis in the transverse and sigmoid sinuses was evident on cranial CT and CT angiography. In our review of the English-language literature we were unable to find any previously published direct images of sinus thrombosis in idiopathic HES.

Clinical diagnostic utility of contrast-enhanced three-dimensional fluid-attenuated inversion recovery for selection of brain biopsy sites in neurosarcoidosis: A case report.

Neurosarcoidosis is difficult to diagnose, because definite diagnosis requires detailed histology of the central nervous system. Three-dimensional contrast-enhanced fluid-attenuated inversion recovery (CE-FLAIR) is more useful for detecting leptomeningeal lesions compared with 3D CE-T1 weighted imaging. However, the clinical diagnostic utility of 3D CE-FLAIR for neurosarcoidosis is unclear. We describe a case of a 46-year-old Japanese woman who was admitted to our department due to chronic headache with fever and diplopia. Using 3D CE-FLAIR, we performed brain biopsy from right cerebellar lesion. The histological examination revealed typical non-caseating granulomas, indicating neurosarcoidosis. Our findings suggest that 3D CE-FLAIR may detect leptomeningeal lesions that are candidates for biopsy in chronic meningitis undetermined etiology.

Fourth Ventricle Outlet Obstruction with Expanding Space on the Surface of Cerebellum.

BACKGROUND: Hydrocephalus is classified as noncommunicating and communicating based on whether all ventricular and subarachnoid spaces are communicating. Although the diagnosis between the two different states is crucial, it is difficult in certain conditions. In particular, communicating hydrocephalus and noncommunicating hydrocephalus owing to fourth ventricle outlet obstruction are highly misdiagnosed. We describe a case of fourth ventricle outlet obstruction of unknown origin that was initially misdiagnosed as communicating hydrocephalus. CASE DESCRIPTION: A 66-year-old woman with gait disturbance and incontinence caused by hydrocephalus underwent ventriculoperitoneal shunt surgery. After 9 months, her fourth ventricle became enlarged and could not be controlled by lowering the shunt pressure. Magnetic resonance imaging (MRI) demonstrated obstruction at the foramen of Magendie, foramina of Luschka, and the cerebral aqueduct. Endoscopic surgery for aqueduct plasty with third ventriculostomy was planned. Because the aqueduct was observed to open spontaneously, only the standard third ventriculostomy was performed. When MRI findings were reviewed retrospectively, an unnatural space was observed between the lower cranial nerves and cerebellar hemisphere that grew along with the fourth ventricular enlargement. This space was determined by MRI cisternography to be the cystic membrane ballooning out from the foramen of Luschka. The primary hydrocephalus likely resulted from fourth ventricle outlet obstruction. CONCLUSIONS: Enlargement of the whole ventricular system with an expanded space between the lower cranial nerves and cerebellar hemisphere can be caused by fourth ventricle outlet obstruction. In such cases, preoperative evaluation of anatomic architecture and cerebrospinal fluid obstruction using MRI cisternography is essential and leads to a successful endoscopic strategy.

Cavernous sinus dural arteriovenous fistula complicated by pontine venous congestion. A case report.

BACKGROUND: Brainstem venous congestion is a rare but serious complication of the CS-dAVF (cavernous sinus dural arteriovenous fistual). CASE DESCRIPTION: A 71-year-old woman presented with right abducens nerve palsy. Brain MRI showed a solitary lesion in the right upper pons. Cerebral angiogram revealed the right CS-dAVF with retrograde venous drainage into the cerebellar cortical veins and the anterior pontomesencephalic vein. The patient was treated with stereotactic radiosurgery, resulting in complete resolution of the pontine lesion and the neurologic symptom. CONCLUSION: A solitary brainstem lesion can be caused by CS-dAVF as a rare complication. Careful diagnosis and treatment are important to avoid permanent neurologic deficits.

Intraspinal dissemination of intracranial hemangiopericytoma: Case report and literature review.

BACKGROUND: The authors report the case of a 53-year-old woman suffering from thoracic myelopathy caused by intraspinal dissemination of hemangiopericytoma. In literature, hemangiopericytoma is commonly found as an intracranial lesion, and often hematogenously metastasizes to the bone or liver; however, intradural spinal dissemination is extremely rare. CASE DESCRIPTION: The patient presented with gait disturbance due to thoracic myelopathy 6 years after surgical treatment for intracranial hemangiopericytoma. Magnetic resonance imaging demonstrated intradural disseminated lesions compressing the spinal cord. Although the patient underwent resection of the intradural spinal tumor, the lesion was tightly adherent to the dorsal surface of the spinal cord. Therefore, it resulted in subtotal removal. Immediately after the surgery, symptoms related to the thoracic myelopathy resolved. The patient was free from disease progression for 14 months after whole spine radiotherapy. CONCLUSION: Recognition of this type of progression is important in the clinical management of intracranial hemangiopericytoma because intradural spinal dissemination dramatically degrades neurological functions.

[A case of secondary anterior fossa dural arteriovenous fistula following posterior fossa craniotomy].

The etiology of dural arteriovenous fistula (AVF) remains uncertain. The authors present a case presenting with anterior fossa dural AVF, which developed after the resection of cerebellar arteriovenous malformation (AVM). The anterior fossa dural AVF, which was not observed on the preoperative angiography, was diagnosed on the follow-up angiography, after the resection of cerebellar AVM. A mechanism underlying the present case is not clearly understood. To the best of our knowledge, some cases of dural AVF secondary to craniotomy have been reported. It is postulated that intracranial vascular anomaly should be analyzed after the surgery.

[A case of the lateral ventricle lesion mimicking arachnoid cyst treated by neuroendoscopic surgery].

A 12-year-old female suffered from intermittent headache with nausea. Neuroradiologic studies demonstrated a cystic lesion in the right trigone with content like cerebrospinal fluid. The right inferior horn was isolated and increased in size. Eodoscopic fenestration was attempted using a flexible fiberscope via the inferior horn. Postoperative magnetic resonance image revealed shrinkage of the cyst and reduced size of the right inferior horn. Intermittent headache dissapeared. Neuroendoscopic treatment is a less invasive and effective therapy for intraventricular arachnoid cyst as well that in the other intracranial lesion.