Dural plasmacytoma mimicking meningioma in a young patient with multiple myeloma.

Intracranial involvement in multiple myeloma (MM) is rarely found, especially with dural involvement. There are only a few cases found concerning MM with intracranial involvement. MM usually involves an older group of patients. Cases involving young patients are very rare. The differential diagnosis of a dural plasmacytoma includes meningioma, metastasis, lymphoma and sarcoma of the dura mater. We present a young patient, 33 years old, with MM presenting an intracerebral mass mimicking meningioma on MRI. MM was diagnosed the previous year. The patient presented with headache, balance disturbance and back pain. MRI revealed an occipital extra-axial mass with a dural tail. Histopathological examination after excision showed MM. Published literatures on intracranial involvement of MM are also discussed. Plasmacytoma should be considered in the differential diagnosis of a solitary dural mass, particularly in a patient with MM.

Cerebral circulation in moyamoya disease: a clinical study using transcranial Doppler sonography.

Transcranial Doppler sonography was performed on eight patients diagnosed as Moyamoya disease. Angiographically, the patients-four adults (mean age 42) and four children (mean age 7.7)-underwent a complete six- or five-vessel angiographic study. The results showed the following: (1) Despite the presence of stenosis, all middle cerebral arteries showed very low-flow velocity compared to their ipsilateral distal internal carotid arteries. In adult cases, the difference was very significant (p < 0.02). (2) Relatively high-flow velocity was observed in the posterior cerebral arteries of children, and in the ophthalmic arteries of adult cases. (3) In several occasions, very low-flow velocity values were still detected despite the fact that with angiography, the respective arterial segments were hardly opacified. The relation and discrepancy between these results and the angiographic findings, and the potential application of transcranial doppler in assessing and grading the severity of moyamoya disease are discussed.

Hyperaemia prior to acute cerebral swelling in severe head injuries: the role of transcranial Doppler monitoring.

Acute cerebrovascular congestion after a closed head injury is significantly related to intracranial hypertension. As an indirect method of cerebral blood flow measurement; transcranial doppler sonography (TCD) provides a rapid and noninvasive assessment of cerebral haemodynamics, including hyperaemic conditions. TCD examinations was serially performed in 35 patients with severe head injury with intact cerebral circulation; i.e. the mean flow velocity (MFV) patterns of the middle cerebral artery (MCA) did not show signs of cerebral circulatory arrest such as systolic spike, to and fro, or no flow. The results showed that the MFV of the MCAs and ipsilateral extracranial internal carotid arteries (ICAs) in 9 of these patients increased sharply and pulsatility index (PI) decreased during 48-96 hours after the injury. This was soon followed by patterns of high intracranial resistance, consistent with elevated intracranial pressure (ICP) in monitored patients and acute brain swelling on repeated computed tomographic (CT) scans. The correlation between increased MFVs, decreased PIs, and cerebral haemodynamic changes leading to acute brain swelling is discussed. The number of patients who ended with severe disability, vegetative state, or death was 66% in this group of 9 patients, compared to only 34% for the 35 patients overall with severe head injury. Though the morbidity and mortality rates largely depend on the primary injury, the presence of acute cerebral swelling aggravate the grave course in these patients. And the ability of TCD to monitor the hyperaemic state prior to oedema should lead us to adjust the therapy in order to minimize the secondary insult related to intracranial hypertension.

Prenatal diagnosis of open spina bifida by MRI and ultrasonography.

A case that was diagnosed prenatally as having open spina bifida by magnetic resonance imaging (MRI) and ultrasound (US) examination is reported. At the time of the third US examination, the spina bifida cystica was detected, but it could not be determined by US whether it was open or closed spina bifida. A lumbosacral skin defect was detected on MRI, which permitted prenatal diagnosis of open spina bifida. Surgical repair was performed immediately after delivery. Prenatal intrauterine evaluation of the fetal CNS morphology and malformation has advanced with the improvement of diagnostic tools. Each diagnostic tool, however, has its own advantages and disadvantages. In prenatal intrauterine evaluation, it is important that observation be made through the combined use of multiple diagnostic tools.

MRI visualization of complete bilateral optic nerve involvement by pituitary adenoma: a case report.

With large pituitary adenomas, the optic nerves and chiasm usually lie on the tumour capsule and are displaced superiorly. We report a large invasive pituitary adenoma, with complete involvement of both optic nerves. Review of the preoperative MR images demonstrated the optic nerves, with signal intensity close to that of cerebral white matter, and different from the flow void of the basal cerebral arteries. Correlation of this observation with intraoperative findings is discussed.

Transcranial Doppler sonography in carotid-cavernous fistulas: analysis of five cases.

Transcranial doppler sonography was performed transorbitally in five patients clinically diagnosed as unilateral carotid-cavernous fistula. Dural arteriovenous malformation related-shunts were detected in all the patients. In the normal eyes, the only doppler signals observed at an insonation depth of 45 to 55 mm were those of the ophthalmic artery. In the affected eyes, abnormal doppler signals with relatively higher flow velocity and lower resistance were observed. In three of the cases, these abnormal signals showed a flow directed anteriorly or away from the cavernous sinus, consistent with changes in the ophthalmic veins caused by the presence of the shunts. In two cases, however, the observed flows were directed posteriorly, the normal direction of these veins. The possible explanations for this discrepancy are discussed in relation with angiographic findings. The use of transcranial doppler might provide a better understanding about hemodynamic changes in carotid cavernous fistulas.

Moyamoya disease associated with pituitary adenoma--report of two cases.

Moyamoya disease associated with prolactin (PRL)-producing pituitary adenomas occurred in two females with elevated blood PRL levels (285 and 120 ng/ml). Computed tomography revealed cystic tumors extending from the sella turcica to the suprasellar cistern. Carotid angiography demonstrated stenoses or obstructions of the bilateral internal carotid arteries at their end point and development of bilateral basal moyamoya vessels. Histological diagnosis in one case was PRL-producing chromophobe adenoma. No stigmata of neurofibromatosis or any history of irradiation was found. Compression of carotid arteries by the tumor was unlikely. These cases should therefore be classified as moyamoya disease accompanied by brain tumor, a very rare occurrence. The hypothalamic disturbance caused by moyamoya disease may have induced the hyperprolactinemia, resulting in secondary prolactinoma.

Intracranial metastasis from a spinal cord primitive neuroectodermal tumor: case report.

A patient with intracranial seeding from a spinal cord primitive neuroectodermal tumor with ependymal differentiation is presented. The first and second stages of intracranial dissemination were well controlled by a combination of irradiation and chemotherapy. The authors review previously published cases and discuss the possible mechanism of seeding from the spinal cord to the intracranial region.

A case of scalp cavernous hemangioma simulating sinus pericranii.

The authors report a case of cavernous hemangioma in the occipital region, which resembled sinus pericranii, protruded in the recumbent posture. A 28-year-old male was admitted with a chief complaint of an occipital fluctuating mass, 5cm in diameter, accompanied by slight pain. The skull X-P was normal. A direct puncture revealed that the lesion was a blood cyst. A cystogram by percutaneous needle puncture revealed paramedian blood pooling with some draining veins but did not show any transcranial communicating vessels. A T2 weighted MR image demonstrated a well demarcated high intensity lesion just beneath the corium. The subtotally removed specimen turned out to be a cavernous hemangioma. We discerned a conceptual confusion of pseudosinus pericranii with scalp cavernous hemangioma, based on the literature review. And we propose that scalp cavernous hemangioma, even if it changes its size according to posture, should not be simply designated as sinus pericranii.

Intraventricular hemangiopericytoma--case report.

A very rare large intraventricular hemangiopericytoma occurred in a 41-year-old male with a 2-month history of headache and paresthesia of the right shoulder and arm. The tumor was partially removed, followed by 50 Gy local Linac irradiation given over 6 weeks. Four months later the residual tumor demonstrated a marked decrease in size and vascularity. The residual tumor was totally removed with less operative bleeding than at the initial operation. This is the first reported case of hemangiopericytoma located in the trigone of the lateral ventricle.

A new model of brainstem ischemia by embolization technique in cats.

An experimental model of brainstem ischemia was developed by embolization technique with cylindrical silicone rubber emboli in cats. The embolus reached the basilar artery in 55 cats (58.5%) and stopped in the upper basilar artery (UB) in 32, the middle basilar artery (MB) in 22 and the lower basilar artery (LB) in one animal. When the basilar artery distal to the embolus was not visualized (type 1) by postoperative vertebral angiogram, Evans blue extravasation was observed in the brainstem caudal to the embolus. When only a filling defect of the basilar artery at the site of the embolus was noted (type 2), dye extravasation was observed in the brainstem around the site of the embolus. In UB type 1, the regional cerebral blood flow of pons and medulla oblongata decreased immediately after embolization, and six hours after embolization it was 11.4 +/- 5.7 (pons) and 11.7 +/- 4.6 ml/100 g/min (medulla oblongata). In UB type 1 and MB type 1 animals, coma, apnea, tetraplegia, and disturbance of swallowing were noted. These animals died within 50 hours after embolization. Animals of UB type 2 and MB type 2 showed neurological deficits, but survived for three days. This paper discusses this method of producing experimental brainstem ischemia, the sites of ischemic lesions, and clinicopathological findings.

Vasospasm after traumatic subarachnoid haemorrhage: transcranial Doppler evaluation. Case report.

A case of vasospasm after traumatic subarachnoid haemorrhage (SAH) is reported here. Transcranial Doppler Sonography (TCD) was used to evaluate mean flow velocity (MFV) changes of the basal cerebral arteries related to vasospasm. Acceleration of MFV of the right middle cerebral artery (MCA) indicating vasospasm was first noted on TCD evaluation, and then proved by carotid angiography (CAG). Evaluation of all TCD results revealed that the process of relaxation or normalization of the spastic artery started from the proximal side of the basal intracranial artery and gradually moving to the distal side. This interesting phenomenon could be a common process found in vasospasm cases.

Changes of brainstem auditory evoked responses (BAERs) in a brain stem ischemic model using embolization technique in cats, a preliminary study.

In order to evaluate brain stem dysfunction related to ischemic process, the authors monitored the Brainstem Auditory Evoked Responses (BAERs) with time in a brain stem ischemic model. 19 adult mongrel cats were divided into two groups: embolization (n = 14) and sham operated control (n = 5). Embolization was done by injecting cylindrical silicone embolus to the right vertebral artery. Each successful embolization of the basilar artery was then confirmed by vertebral angiography. BAERs were monitored before embolization and then 5-10 min, 15 min, 30 min, 60 min, 3 hr and 6 hr after embolization. The presence of ischemic lesion caused by embolization was confirmed by injecting 2% Evans blue solution 30 min before sacrificing the animals. Leakage of the dye was observed. In embolized animals, significant (Student t test, p less than 0.05) delay of interpeak latencies of waves 1-3, 3-5, and 1-5 was observed 15 min after embolization. This delay became more significant (p less than 0.01) 30 min after embolization. These results provide evidence for the usefulness of BAERs monitoring which can be used to complement other diagnostic methods for patients with vertebrobasilar insufficiency and/or infarction.

An investigation of vascular anatomy and microvascular architecture of the brainstem in cats.

The vascular anatomy and microvascular architecture of the vertebrobasilar system, especially within the brainstem, was investigated in cats. The main branches of the basilar artery were observed and the inner diameters of these vessels were measured on vertebral angiograms. The three-dimensional microvascular architecture was constructed using molded vascular models. The arterial anastomoses between the arteries inside the brainstem were studied using contact microangiograms. The paramedian branch penetrated into the brainstem in a retrograde fashion from the cranial basilar artery, and in an anterograde fashion from the caudal basilar artery. Arterial anastomoses were noted between the circumferential arteries. The frequency of arterial anastomoses was higher and diameters of the anastomotic vessels were larger in the ventrolateral region of the brainstem than in the ventromedial region. Regarding the perforating arteries, the arterial anastomoses were present outside the brainstem. No arterial anastomoses were found inside the brainstem.