1/56. Biologic heterogeneity of angiomatous meningiomas.Three angiomatous meningiomas, classified histologically as benign, were analyzed cytogenetically and examined for the expression of EGF/PDGF and their receptors by immunohistochemistry. An accumulation of p53 protein and the presence of mutations in exons 5-8 of the p53 gene in neoplastic cells were also determined. In one tumour, chromosome studies revealed near diploid karyotype with the loss of chromosome 22. Two other meningiomas revealed tetraploid karyotypes with the presence of telomeric associations and a wide spectrum of numerical, complex chromosome aberrations. Moderate EGF and EGFR immunoreactivity was found in three and one meningioma, respectively. All tumours exhibited diffuse PDGF and PDGFR-beta expression. No p53 gene mutations were found, but one tumour expressed strong and dispersed p53 immunopositivity. This findings reflect the biological heterogeneity of angiomatous meningiomas.- - - - - - - - - - ranking = 1keywords = near (Clic here for more details about this article) |
2/56. meningioma of the pituitary stalk without dural attachment: case report and review of the literature.OBJECTIVE AND IMPORTANCE: Tumors in the suprasellar region such as adenomas of the pituitary gland, craniopharyngiomas, nonneoplastic cystic lesions (especially Rathke's cleft cysts), and meningiomas are frequently encountered in neurosurgical practice. Meningiomas originate from the arachnoid layer connected to the dura of the anterior or posterior clinoidal process, or the tuberculum, dorsum, or diaphragma sellae. Tumors originating from the pituitary stalk are rare. Such lesions may include germinomas, astrocytomas, histiocytosis X, hamartomas, and sarcoidosis. We report a patient with a suprasellar meningioma originating from the pituitary stalk with no connection to the adjacent dura. CLINICAL PRESENTATION: A 50-year-old man was assessed for impotence and loss of libido. physical examination revealed no abnormalities. Endocrinological investigations disclosed nearly complete hypopituitarism, and magnetic resonance imaging revealed a suprasellar homogeneously enhancing tumor. INTERVENTION: Complete surgical resection was performed in an endoscope-assisted right-sided supraorbital craniotomy. The tumor originated from the pituitary stalk with no connection to the surrounding dura. The histopathological diagnosis was meningioma. CONCLUSION: Although meningiomas frequently occur in the suprasellar region, this patient with a suprasellar meningioma is unique because the tumor originated from the pituitary stalk with no connection to the surrounding dura. The absence of dural attachment has been described in 43 extracerebral meningiomas, but a suprasellar location has been reported only once previously. Recognition of this phenomenon is important, because meningiomas require a different therapeutic strategy than most other tumors of the pituitary stalk.- - - - - - - - - - ranking = 1keywords = near (Clic here for more details about this article) |
3/56. Far lateral approach with intraoperative ultrasound Doppler identification of the vertebral artery.A 69-year-old woman presented with right hemiparesis and magnetic resonance imaging revealed a meningioma at the ventral aspect of the foramen magnum. We used a retromastoid curvilinear incision down the lateral aspect of the neck to expose the semispinalis and other muscles. Guided by ultrasound to avoid damage to the vertebral artery beneath the semispinalis, we incised the semispinalis muscle in a U-shape that hinged at the retromastoid curvilinear incision with its one limb along the border of the foramen magnum and the other limb along the posterior arch of the atlas. The other muscles were divided in line with the curvilinear incision and retracted posteriorly with the bulk of semispinalis to expose the bones, not disturbing the U-shaped piece of semispinalis that covered the vertebral artery. Similarly guided by ultrasound, we performed far lateral suboccipital craniectomy and laminectomy, exposed the dura above and below the dural entry of the vertebral artery, opened the dura cephalad and caudal to the dural entry of the vertebral artery, and excised the tumor. This method provided adequate exposure to the lateral aspect of the cranio-vertebral junction and minimized the risks of dissecting the whole extradural segment of vertebral artery. It requires more cases to determine whether the results of this patient can be generalized.- - - - - - - - - - ranking = 3keywords = near (Clic here for more details about this article) |
4/56. MRI appearances mimicking the dural tail sign: a report of two cases.We report two cases in which the MRI appearances mimicked the dural tail sign; a glioma extending into the subarachnoid space, and a meningioma extending to the subdural space. They indicate that tumour invasion into the subarachnoid or subdural space, should be considered when prominent linear enhancement is observed along the dura mater adjacent to tumours.- - - - - - - - - - ranking = 1keywords = near (Clic here for more details about this article) |
5/56. Extended middle fossa surgery for meningiomas within or at the internal auditory canal.OBJECTIVE: To show the clinical outcome in patients with meningioma within or at the internal auditory canal (IAC) operated on by the extended middle cranial fossa approach. STUDY DESIGN: Retrospective case review. SETTING: A tertiary referral center. patients: Twelve patients, 9 women and 3 men, whose ages ranged from 37 to 70 years (mean 57 years). One tumor was entirely intracanalicular, 5 had an intra-extracanalicular growth, 3 were centered at the posterior porus lip, and 3 tumors were localized in the midpetrosal region with spread into the IAC. INTERVENTION: Extended middle cranial fossa approach. MAIN OUTCOME MEASURES: magnetic resonance imaging and computed tomography were used for follow-up and reevaluation of the operative sites. facial nerve function and hearing were examined. RESULTS: Complete resection was achieved in 10 (83%) of 12 patients. The retrosigmoid approach was necessary to complete tumor resection in one patient, and in another, partial resection was done because of the en plaque type of tumor growth. There was one unexpected recurrence. All patients retained normal or near-normal facial nerve function postoperatively. Three patients were deaf before surgery, and preoperative hearing level was preserved in 42%. CONCLUSIONS: Attempted hearing preservation surgery is justified in patients with small tumors and preserved hearing, because tumor exposure and safety of resection are comparable with that of hearing-destructive procedures. Lateral extension of the tumor to the fundus does not prevent complete resection with preservation of function, and elective bone resections beyond the visible tumor margins seem not to substantially influence the tumor recurrence rates.- - - - - - - - - - ranking = 1keywords = near (Clic here for more details about this article) |
6/56. Surgical strategy for meningioma extension into the optic canal.neuroimaging of the extension of meningioma into the optic canal was evaluated for planning the surgical strategy. Intracanalicular extension and localization were retrospectively analyzed in 13 patients with frontal base meningioma near the optic canal, based on the findings of visual field defects, magnetic resonance (MR) imaging, and surgical observations. MR imaging confirmed intracanalicular localization in one of three patients with tumors extending into the optic canals, and indicated the tumor in the others. The visual field defect did not precisely correspond to the tumor localization. Unroofing of the optic canal was performed in four patients and no adverse effects were observed. The interhemispheric approach was employed for tumors localized medially in the canal, and the pterional approach for tumors localized laterally. MR imaging is useful to evaluate the intracanalicular extension, but aggressive confirmation during surgery is essential. Tailored unroofing of the optic canal and removal of the intracanalicular tumor can be performed with few adverse effects and results in good tumor control.- - - - - - - - - - ranking = 1keywords = near (Clic here for more details about this article) |
7/56. Hearing restoration from deafness after resection of a large cerebellopontine angle meningioma--case report.A 61-year-old man presented with a large cerebellopontine angle meningioma manifesting as a 1-year history of deafness on the right side, in whom hearing was restored from the deaf state immediately after tumor resection. neuroimaging demonstrated a large mass in the right cerebellopontine angle, originating at the region adjacent to the jugular foramen. audiometry showed his hearing was off-scale (> 105 dB) on the right. The tumor was successfully removed through the retrosigmoid approach, and the integrity of the 7th and 8th cranial nerves was maintained. The patient regained hearing on the day after the operation, which continued to improve until near-normal. The 8th cranial nerve function may recover dramatically after removal of non-acoustic tumors, even if preoperative hearing loss is profound. To maximize the opportunity to regain hearing, approaches which devastate cochlear function should be avoided and more meticulous manipulation during tumor removal is needed.- - - - - - - - - - ranking = 1keywords = near (Clic here for more details about this article) |
8/56. Primary meningeal sarcomas in two children.Primary meningeal sarcomas are rare but highly aggressive tumors predominantly affecting children. The clinical course, imaging characteristics and histopathological features of meningeal sarcomas in two pediatric patients are presented. Furthermore, we critically discuss the new WHO classification of these entities comparing them to older descriptions. In a 6-year-old girl, a cranial computed tomography (CT) scan was performed, after a mild head trauma, showing a parieto-occipital hemorrhage. One month later, a circumscribed mass adhering to the meninges and with central areas of hemorrhage was evident on magnetic resonance imaging (MRI) scans. brain biopsy revealed a polymorphocellular sarcoma originating from the leptomeninges and infiltrating the brain. In an 8-year-old girl, who presented with headaches and vomiting, several MRI-examinations were inconspicuous for nearly one year until the latest MR-scan revealed a diffuse contrast enhancement of the leptomeninges of the whole brain and spinal canal. After open biopsy, primary leptomeningeal sarcomatosis was diagnosed. Although CT and MRI did not allow a specific diagnosis in both cases the exact visualization of the extent of the tumor and/or meningeal involvement was possible. Since there are no specific imaging criteria to differentiate meningeal sarcoma from other solid brain tumors or from other tumoral or inflammatory meningioses brain biopsy is indispensable. In order to avoid misinterpretations and delays of therapy, early open brain biopsy or surgical resection of the lesion is necessary in cases of unclear brain masses, especially of unclear meningeal processes. Due to the low number of cases published so far, the biological behavior and clinical management of this tumor entity still awaits further investigation.- - - - - - - - - - ranking = 1keywords = near (Clic here for more details about this article) |
9/56. Scrape cytology of meningioangiomatosis: a report of two cases with diagnostic cytologic features.BACKGROUND: Meningioangiomatosis is a rare, probably hamartomatous condition characterized by nonneoplastic intracortical proliferation of meningothelial cells, capillaries and fibroblasts. The lesion may mimic a tumor both clinically and radiologically. We present two cases of the entity, including its cytologic features. CASES: A 71-year-old man presented with an eight-month history of headache, change in vision, loss of depth perception and unsteady gait. Magnetic resonance imaging (MRI) revealed an infiltrative lesion of the left occipital lobe, diffuse in nature. Cytologic smears prepared at the time of intraoperative consultation showed numerous thin-walled capillaries together with bland spindle cells. Occasional large cells with prominent nucleoli were also present. Frozen section confirmed the presence of linear, small capillaries surrounded by fibroblasts and meningothelial cells, consistent with meningioangiomatosis. The second case was a 3-year-old girl who presented with a one-day history of seizure, vomiting, fever and perioral cyanosis. MRI revealed an enhancing lesion in a temporal lobe of the cerebrum. The patient underwent excision of the lesion. Intraoperative cytology showed numerous meningothelial whorls together with neurons and occasional capillaries. Both patients were well, one after three months and the other after six. CONCLUSION: Meningioangiomatosis is a lesion characterized by linear capillaries, meningothelial cells and neurons, some exhibiting nuclear atypia. The combination can lead to an erroneous diagnosis of more common conditions, such as meningioma (with intracortical extension) and anaplastic astrocytoma. Contrary to these more sinister diagnoses, meningioangiomatosis is a completely benign, presumably hamartomatous entity.- - - - - - - - - - ranking = 2keywords = near (Clic here for more details about this article) |
10/56. Systemic non-Hodgkin's lymphoma with optic nerve infiltration in a patient with AIDS.PURPOSE: To report the clinicopathologic features of a patient with AIDS and clinically regressed systemic non-Hodgkin's lymphoma who subsequently developed lymphomatous infiltration of the optic nerve and occlusion of the central retinal vein in both eyes. methods: The eyes of this patient were examined ophthalmologically and by fluorescein angiography. The eyes, brain, and body were obtained after death and studied by light microscopy. RESULTS: Ophthalmic examination and fluorescein angiography revealed optic nerve swelling and central retinal vein occlusion first in the left eye and shortly thereafter in the right eye. Postmortem histopathologic examination showed dense infiltration of both optic nerves by lymphoma as well as necrotizing vasculitis involving the retinal vessels near the left optic nerve head. Examination of the brain revealed lymphomatous involvement in the paraventricular region with associated necrosis and inflammation. No bone marrow recurrence or other residual systemic lymphoma was present. CONCLUSION: This case demonstrates that infiltrative optic neuropathy may occur as the sole ocular manifestation of disease recurrence in a patient with systemic non-Hodgkin's lymphoma otherwise thought to be in clinical remission.- - - - - - - - - - ranking = 1keywords = near (Clic here for more details about this article) |
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