Calcified vestibular schwannoma in the cerebellopontine angle

Although vestibular schwannoma is a common tumor in the cerebellopontine angle, calcified vestibular schwannoma is rare. A 59-year-old woman with sudden onset epileptic seizures, was referred to Hokkaido Neurosurgical Memorial Hospital. Neurological examination revealed left Bruns nystagmus, left deafness and left cerebellar ataxia. Brain MRI revealed a mass, about 3cm in diameter, in the left cerebellopontine angle. The mass showed heterogeneous intensity on T1- and T2-weighted and fluid-attenuated inversion recovery (FLAIR) images. Hydrocephalus was seen. On CT scan, the tumor was calcified. Preoperatively, vestibular schwannoma, meningioma, cavernous hemangioma, or thrombosed giant aneurysm were considered as differential diagnoses. The pathological diagnosis was schwannoma. For a calcified mass in the cerebellopontine angle, vestibular schwannoma should be considered in the differential diagnosis to plan appropriate treatment strategies.     

显微手术治疗小脑海绵状血管瘤

目的总结小脑海绵状血管瘤的临床表现及手术治疗效果。方法对12例均经手术切除和病理证实的小脑海绵状血管瘤进行回顾性分析。结果11例急性起病,表现为小脑自发性出血。慢性起病1例,表现为渐进性共济失调、行走不稳。头颅MRI平扫与增强多表现为T1高信号,T2高或混杂信号,病灶周围有环形低信号带。磁敏感加权成像序列（SWI）更有助于诊断。12例均采用显微手术治疗,所有病灶均完整切除,疗效满意。结论自发性出血是本病的主要症状,多有共济失调等小脑受损体征。MRI具有较高的诊断特异性,手术是处理小脑海绵状血管瘤安全和有效的首选方法。     

Giant thrombosed aneurysm of the left vertebral artery developing in the fourth ventricle

A case of giant, thrombosed, non haemorrhagic aneurysm of the distal portion of the left vertebral artery is reported. The patient came to medical attention with an acute cervical pain after a minimal cervical traumatism and a diagnosis of torticollis from rheumatologic cause was made. In fact, a few weeks before, he had suffered three episodes of right homonymous hemianopsia. Subsequently, hiccup, vomiting, orthostatic dizziness with postural hypotension appeared, suggesting a medullary lesion. CT scan showed a round, heterogeneous high-density lesion near the fourth ventricle. Angiography was normal. MRI showed an oval mass in the fourth ventricle, between the medulla and the cerebellum. Surgery found an aneurysm of the end of the left vertebral artery.     

Totally thrombosed giant P2 aneurysm: a case report and review of literature.

The diagnosis and treatment of intracranial saccular giant aneurysms is still difficult despite developments in neuroradiology, neuroanesthesiology and micro-neurosurgery. These aneurysms are usually located on major intracranial arteries and are rarely on distal branches of these arteries. An extra-axial 4 x 5 cm mass lesion in the left mediobasal temporal region was detected on the CT and MRI examinations of a 37 year old male patient who was admitted to our institution with headache and slight right-sided hemiparesis lasting for 2 months. The lesion was avascular on angiography. Surgery proved that the lesion was a totally thrombosed giant aneurysm of the P2 segment of posterior cerebral artery (PCA). The P2 segment was clipped proximal to the aneurysm with pterional-transsylvian approach and the aneurysm was totally excised. Giant aneurysms of the P2 segment are rare and 15 cases have been reported in the literature. This report presents a rarely seen totally thrombosed giant P2 aneurysms and discusses the difficulties in diagnosis and treatment.     

Giant cerebral cavernoma. Case report with literature review

Giant cerebral cavernoma is a rare malformation classified as a brain occult vascular lesion. We report a case of initially misdiagnosed giant cavernous angioma revealed by a spontaneous intracerebral hemorrhage. A 40-year-old woman was admitted with right hemiplegia and altered consciousness occurring 3 days prior to presentation. A non-contrast CT scan showed a left parietal gross hematoma, and she was immediately taken to the operating room for emergency surgery. However, the procedure was interrupted by massive bleeding, and therefore a vascular lesion was suspected. Magnetic resonance images suggested a giant cavernous malformation. Afterward, she underwent total removal of this lesion. The postoperative period was uneventful, and histopathological examination confirmed the diagnosis of cavernous angioma. Thus, the differential diagnosis of gross spontaneous intracerebral hematoma should include giant cavernous angioma.     

Endovascular treatment of a large partially thrombosed basilar tip aneurysm

Despite the remarkable developments in neurosurgical and neuro-interventional procedures, the optimal treatment for large or giant partially thrombosed aneurysms with a mass effect remains controversial. The authors report a case of a partially thrombosed aneurysm with a mass effect, which was successfully treated by stent-assisted coil embolization. A 41-year-old man presented with headache. Brain computed tomography depicted an 18×18 mm sized thrombosed aneurysm in the interpeducular cistern. More than 80% of the aneurysm volume was filled with thrombus and the canalized portion beyond its neck measured 6.8×5.6 mm by diagnostic cerebral angiography. Stent-assisted endovascular coiling was performed on the canalized sac and the aneurysm was completely obliterated. Furthermore, most of the thrombosed aneurysm disappeared in the interpeduncular cistern was clearly visualized follow-up brain magnetic resonance imaging conducted at 21 months. The authors report a case of selective coiling of a large, partially thrombosed basilar tip aneurysm.     

Dural cavernous angioma mimicking a meningioma and causing facial pain.

An 18-year-old girl who had severe headaches in the left temporal and facial regions was found to have a small enhanced dural-based parietal convexity mass. On magnetic resonance imaging (MRI), this mass was homogeneously enhanced with "dural tail sign," and was similar to a meningioma. This mass was completely removed surgically, and pathology proved it to be a cavernous angioma without previous hemorrhages. The patient's facial pain was dramatically relieved after surgery. A small dural mass causing severe facial pain is an unusual situation. The lack of hemosiderin in the extra-axial cavernous angioma often leads to the preoperative diagnosis of meningioma.     

A diagnostic pitfall: Angiosarcoma of the brain mimicking cavernous angioma.

Primary or secondary angiosarcoma in the central nervous system is rarely reported. We present a rare case of cerebral angiosarcoma, which comprised both poorly-differentiated solid areas and well-differentiated areas that led to the misdiagnosis of cavernous angioma. A 79-year old woman presented with an intracerebral hematoma in the left frontal lobe that was misdiagnosed as a hemorrhage from a cavernous angioma at initial operation. At a second surgery, the lesion was diagnosed as angiosarcoma involving the cerebellum, heart, femur, sacro-iliac bones and other locations. An autopsy suggested that the angiosarcoma of the heart was the primary lesion, which was occult at the time of the initial operation. Angiosarcoma may have areas with different degrees of differentiation and when a cavernous angioma is suspected histopathologically, the specimen should also be carefully explored for poorly-differentiated areas and the diagnosis of primary or secondary angiosarcoma considered.     

Congenital cavernous angioma exhibits a progressive decrease in size after birth

Case report We report a case of congenital intracranial cavernous angioma, which was initially found at a gestational age of 34 weeks in utero as a mass lesion associated with hydrocephalus. After birth, the patient was treated for hydrocephalus first by external drainage and then by ventricular peritoneal shunt. The natural course of the mass lesion was observed until the age of 8 months when the histopathological diagnosis confirmed the cavernous angioma after tissue was obtained by surgery. CT scans repeated monthly during this period demonstrated that the angioma continuously decreased in size. There was no evidence of hemorrhage in the angioma on serial CT scans. The histopathology revealed thrombosis of cavernous vessels with hyaloid changes in the angioma.Discussion The mechanisms of the decreasing size of the cavernous angioma have often been discussed in relation to spontaneous hemorrhages and resolution. The present case suggests a mechanism in which the spontaneous formation of a thrombus might be the dominant factor for the decrease in size. Thrombus formation may result from low perfusion due to the large size of the angioma.     

Superficial Temporal Artery to Anterior Cerebral Artery Hemi-bonnet Bypass Using Radial Artery Graft for Prevention of Complications after Surgical Treatment of Partially Thrombosed Large/Giant Anterior Cerebral Artery Aneurysm

Background

Partially thrombosed large/giant aneurysm of the anterior cerebral artery is still challenging because this complex aneurysm requires arterial revascularization in the deep operation field. Therefore, direct neck clipping is often impossible. We describe our experiences with extracranial-intracranial bypass as an insurance bypass prior to clipping of partially thrombosed anterior cerebral artery aneurysms, and discuss the microsurgical technique and strategy.

Bilateral suboccipital approach for a giant vertebral artery aneurysm

Giant thrombosed aneurysms of the vertebral artery (VA) are difficult to treat. Moreover, marked tortuosity of the parent VA complicates determination of the surgical approach. We report the case of a 71-year-old male patient who presented with gait disturbance. Magnetic resonance imaging revealed a giant thrombosed aneurysm of approximately 4 cm in diameter located in the ventral region and to the right of the medulla oblongata. Computed tomography angiography showed that the right VA had extreme tortuosity, and that the VA union was in contact with the left 7th and 8th cranial nerves. Given that the aneurysm was thrombosed and causing a mass effect, we sought to trap it. In this case, because of the tortuous VA, intravascular team considered intravascular therapy to be too difficult. We made a question mark-shaped skin incision and used a wide bilateral suboccipital approach. The VA proximal to the aneurysm was occluded with an aneurysm clip using an approach from the right of the brainstem, while the VA distal to the aneurysm was occluded using a lateral suboccipital approach. When the VA and basilar artery are atherosclerotic and extremely tortuous, the distal and proximal aspects of the aneurysm can exist on both sides of the midline. In difficult cases such as that reported here, in which a giant VA aneurysm exceeded the midline of the anterior surface of the medulla, we believe that it is useful to employ a bilateral approach from both sides of the brainstem.     

Acute subdural hematoma caused by an unruptured,thrombosed giant intracavernous aneurysm

Introduction  Acute subdural hematoma (SDH) is an infrequent complication after aneurysmal subarachnoid hemorrhage. SDH associated with unruputed intracavernous aneurysm has never been reported. Methods  Single patient case report and review of relevent literature. Results  A 65-year-old woman with an unruptured, thrombosed giant intracavernous aneurysm developed an acute SDH 2 days after admission for cavernous sinus syndrome. Despite emergent evacuation of the SDH, the patient never regained consciousness because of brain herniation. Conclusion  Acute SDH is a rare complication of ruptured, giant intracavernous aneurysms. Erosion of the cavernous sinus wall by acute enlargement of the aneurysm after thrombosis is the proposed mechanism for development of the SDH.     

Fetal opercular cavernous angioma causing cerebral cleft: contralateral primitive vascular anomaly and subicular dysgenesis

We describe a 22-week female fetus after pregnancy was terminated because of fetal magnetic resonance imaging showing a large left cerebral hemispheric cleft suggestive of porencephaly or schizencephaly. Postmortem examination revealed a large cavernous angioma of the left opercular region with evidence of previous hemorrhage and extensive cerebral infarction. In the right hemisphere, another vascular malformation within the frontal germinal matrix consisted of an aggregate of primitive vessels not yet canalized. Selective dysgenesis of the right subiculum also was demonstrated. This case illustrates not only a severe encephaloclastic effect of cavernous angioma in fetal brain but also the importance of fetal autopsy to help correlate and explain fetal neuroimaging. Potential future prenatal treatment of fetal angiomata requires precise in utero diagnosis.     

Giant vertebrobasilar junction aneurysms: unusual cases

Giant vertebrobasilar (VB) junction aneurysms are uncommon aneurysms, especially those associated with multiple aneurysms of the posterior circulation. We report two cases, one with a small and a giant aneurysm of the VB junction which were surgically clipped; and the other with a small left anterior inferior cerebellar artery (AICA) aneurysm which resolved spontaneously. The patient, however, developed a de-novo giant VB junction aneurysm, which was detected on a follow-up angiogram. This aneurysm was treated by surgical clipping. The clinical features, angiographic considerations and surgical treatment of such rare conditions are discussed and the relevant literature reviewed.     

Spinal Intradural Extramedullary Cavernoma Presenting with Intracranial Superficial Hemosiderosis

A case of intradural extramedullary cavernous angioma is presented with headache, dizziness, and bilateral sensorineural hearing loss caused by an intracranial superficial hemosiderosis. It was incidentally found in a patient with a 3-month history of sustained headache, dizziness and a 3-year history of hearing difficulty. The neurological examination was unremarkable in the lower extremity. MR images showed an intracranial superficial hemosiderosis mostly in the cerebellar region. Myelography and MR images of the thoracolumbar spine revealed an intradural extramedullary mass, which was pathologically proven to be a cavernous angioma. T12 total laminoplastic laminotomy and total tumor removal were performed without any neurologic deficits. The patient''s symptoms, including headache and dizziness, have been absent for three years. Intradural extramedullary cavernous angioma can present with an intracranial superficial hemosiderosis as a result of chronic subarachnoid hemorrhage.     

Giant true posterior communicating artery aneurysm.

The case of a giant posterior communicating artery (PCoA) aneurysm is reported in which the clinical presentation was Korsakoff's syndrome. Left carotid angiography revealed a partially thrombosed giant PCoA aneurysm. Three-dimensional computed tomography angiography showed the precise neck of aneurysm and surrounding structures from a multidirectional view. Hypoperfusion of the bilateral frontal, temporal, and medial inferior thalamus was seen on single-photon emission computed tomography. According to previous reports, giant true PCoA aneurysms are rare; in fact, there has been only one report of a giant true PCoA aneurysm. We discuss the radiological characteristics and the clinical presentation of giant true PCoA aneurysms.     

Cavernous angioma of the optic tract

Summary A cavernous angioma of the right optic tract in a 35-year-old man is presented. The patient suffered from headaches and had a left homonymous visual field defect after subarachnoid haemorrhage and an intracerebral haematoma in the right temporomedial region, revealed by computed tomography (CT). Follow-up CT showed a small contrast-enhanced lesion in the right suprasellar and parasellar cistern. Angiography on three occasions did not reveal a vascular lesion. Magnetic resonance imaging was helpful both for diagnosis and planning surgical therapy. It showed typical signs of a cavernous angioma of the right optic tract; the diagnosis was confirmed by surgery and histological examination. This appears to be the first reported case of a cavernous angioma of the optic tract.     

两次DSA阴性的颅内破裂动脉瘤1例报道并文献复习

目的 报告1例经两次全脑、全程血管造影阴性的破裂小脑后下动脉动脉瘤患者诊治经验。方法 回顾性分析1例颅内破裂动脉瘤病人的临床资料,包括症状、体征、影像学检查、手术过程及病理结果,分析其脑血管造影阴性的原因。结果 患者为21岁男性,以突发头痛起病,外院头部CT示蛛网膜下腔出血,但脑血管造影未发现动脉瘤,头部MRI检查怀疑脑干背侧海绵状血管瘤。转入我院后,复查全脑、全程血管造影仍然为阴性,复查头部MRI检查再次怀疑海绵状血管瘤并行开颅手术治疗,术中于小脑延髓裂发现病变为豌豆大小。呈结节状,有供血动脉进入口和输出口,术后病理证实为动脉瘤内血栓形成并机化。术后病人恢复良好。将MRI影像与3D-DSA影融合后,发现病变旁有小脑后下动脉通过,考虑为动脉瘤出血后继发血栓形成而闭塞。结论 脑血管造影虽然是颅内动脉瘤诊断的金标准,但是两次脑血管造影阴性仍然不能完全排除颅内动脉瘤,其中原因之一就是动脉瘤出血后继发血栓形成。     

Giant cerebral cavernous haemangioma: a case report and review of literature.

An 18-year-old male presented with uncontrolled left focal seizures with secondary generalisation for the past 10 years. Investigations revealed a large lobulated mass in the right frontal brain. Surgical excision of a giant cavernous haemangioma was performed. The patient is seizure-free following the surgery. The case and relevant literature on the rare entity of giant intracranial cavernous haemangiomas is discussed.     

A case of fibromuscular dysplasia presenting with Wallenberg syndrome, and developing a giant aneurysm of the internal carotid artery in the cavernous sinus]

A 25-year-old man developed Wallenberg syndrome (WS). At that time his carotid angiography was normal. When he was 28 years old, he suffered from retinal artery embolism in the left eye. At the age of 30 years, he had an acute onset of abducens nerve palsy in his right eye. The carotid angiography showed a giant aneurysm at the cavernous sinus portion in the right internal carotid artery. At his age of 38, the right oculomotor, trochlear and trigeminal nerves were involved. A vertebral angiography revealed a bead-like formation, and a diagnosis of fibromuscular dysplasia (FMD) was made. An intensive angiographic examination revealed many stenotic or dilated lesions in the carotid, vertebral, coronary, renal, and hepatic arteries. A sural nerve biopsy specimen revealed that the sural vein was involved. In Japan only one case of FMD presenting with WS is known. FMD should be under consideration as an underlying disease, when WS occurred in younger patients with few risk factors. In this patient an angiography revealed no abnormality in the cavernous sinus portion of the internal carotid artery, when he suffered from WS. However, eight years later he was proved to have a giant aneurysm in the cavernous sinus portion. In conclusion, we support the hypothesis that aneurysm may originate from angiographically normal arterial wall in FMD.