Uncommon Glioneuronal Tumors: A Radiologic and Pathologic Synopsis.

Glioneuronal tumors are characterized exclusively by neurocytic elements (neuronal tumors) or a combination of neuronal and glial features (mixed neuronal-glial tumors). Most of these tumors occur in young patients and are related to epilepsy. While ganglioglioma, dysembryoplastic neuroepithelial tumor, and desmoplastic infantile tumor are common glioneuronal tumors, anaplastic ganglioglioma, papillary glioneuronal tumor, rosette-forming glioneuronal tumor, gangliocytoma, and central neurocytoma are less frequent. Advances in immunohistochemical and molecular diagnostics have improved the characterization of these tumors and favored the description of variants and new subtypes, some not yet classified by the World Health Organization. Not infrequently, the histologic findings of biopsies of glioneuronal tumors simulate low-grade glial neoplasms; however, some imaging findings favor the correct diagnosis, making neuroimaging essential for proper management. Therefore, the aim of this review was to present key imaging, histopathology, immunohistochemistry, and molecular findings of glioneuronal tumors and their variants.

Frameless image-guided neuroendoscopy training in real simulators.

BACKGROUND: Over the last decade, neuroendoscopy has re-emerged as an interesting option in the management of intraventricular lesions in both children and adults. Nonetheless, as it has become more difficult to use cadaveric specimens in training, the development of alternative methods was vital. The aim of this study was to analyze the performance of a real simulator, in association with image-guided navigation, as a teaching tool for the training of intraventricular endoscopic procedures. METHODS: 3 real simulators were built using a special type of resin. 1 was designed to represent the abnormally enlarged ventricles, making it possible for a third ventriculostomy to be performed. The remaining 2 were designed to simulate a person's skull and brain bearing intraventricular lesions, which were placed as follows: in the foramen of Monro region, in the frontal and occipital horns of the lateral ventricles and within the third ventricle. In all models, MRI images were obtained for navigation guidance. Within the ventricles, the relevant anatomic structures and the lesions were identified through the endoscope and compared with the position given by the navigation device. The next step consisted of manipulating the lesions, using standard endoscopic techniques. RESULTS: We observed that the models were MRI compatible, easy and safe to handle. They nicely reproduced the intraventricular anatomy and brain consistence, as well as simulated intraventricular lesions. The image-based navigation was efficient in guiding the surgeon through the endoscopic procedure, allowing the selection of the best approach as well as defining the relevant surgical landmarks for each ventricular compartment. Nonetheless, as expected, navigation inaccuracies occurred. After the training sessions the surgeons felt they had gained valued experience by dealing with intraventricular lesions employing endoscopic techniques. CONCLUSION: The use of real simulators in association with image-guided navigation proved to be an effective tool in training for neuroendoscopy.

Surgical removal of small petroclival meningiomas.

UNLABELLED: Treatment of large petroclival meningiomas causing brain stem compression is surgical removal followed by radiotherapy or radiosurgery if the lesion was partially resected. The management of small petroclival meningiomas is, however, controversial. Clinical observation, radiosurgery and surgical removal are the options of treatment. The natural history of these tumours is not well known. Published series of patients treated with radiosurgery are not comparable with surgical series because the latter also includes large size tumours. In this paper we present a series of 18 patients with small petroclival meningiomas (diameter

Primary central nervous system lymphomas in immunocompetent patients.

OBJECTIVES: Primary central nervous system lymphoma (PCNSL) is a rare pathology and is most often seen in immunodeficient patients. This article presents our casuistic of PCNSL in immunocompetent patients and make a literature review on this issue with focus on recent advances, investigations, and controversies in diagnosis and management of this pathology. MATERIAL AND METHODS: Nine patients operated in the last years in our clinics are analysed in relation to sex, age, time of symptoms, procedures and adjuvant treatment. Posteriorly the results are compared with those in the preview literature. RESULTS: The age ranged from 44-68 years (middle of 66 years); 62.5% of the patients were female. The mean time of symptoms, when the diagnostic was made, was 3.2 months (range 1-6 months). The most common symptoms were hemiparesis (present in 75% of the patients) headache (37.5%) seizures (25%) and ataxia (25%). The most common localization was the parietal, frontal and temporal lobe surface with 25% of the patients for each localization. Five patients (50%) were treated with stereotactic biopsy, three with surgery (37.5%) and one (12.5%) with both of them. Five patients (62.5%) were submitted to pos-operative radiotherapy as adjuvant treatment. In relation to the histology, the most common cell type was Diffuse B Cells. CONCLUSIONS: This study demonstrated that complete surgical resection followed by radiotherapy have shown good results. In opposition to the literature, the authors regard chemotherapy as a secondary line treatment and recommend its use only in some selected cases.

April 2001: a 70 year old woman with recurrent meningioma.

The April Case of the Month (COM). The contributors report a case of a 70 year-old woman with recurrent meningiomas, one of which showed rhabdoid and lipomatous differentiation. Histopathological study of the first and second previous resections showed only typical meningothelial meningioma. On the third craniotomy, a new tumor specimen showed an admixture of classic meningothelial meningioma with lipomatous and rhabdoid foci. Immunohistochemical studies showed diffuse reactivity for epithelial membrane antigen and vimentin, as well as focal positivity for desmin and smooth muscle actin in the areas with rhabdoid features and S100 protein in the lipomatous foci. The presence of these three different and concomitant histological patterns only in the third surgical resection might support a metaplastic origin and, also, corroborates the concept that rhabdoid features are suggestive of an aggressive behavior.

Malignant teratoma of the optic nerve: case report.

An unusual case of a malignant teratoma of the right optic nerve with extension into the chiasm is presented. The preoperative diagnosis was difficult to establish. Complete removal of the lesion with postoperative irradiation was carried out. Eight months after the operation, the patient developed subarachnoid metastases by the cerebrospinal fluid pathway as well as systemic metastases and died. No local recurrence of the tumor was seen at autopsy. The therapeutic possibilities for these lesions are discussed.

Maffucci's syndrome associated with a cranial base chondrosarcoma: case report and literature review.

OBJECTIVE AND IMPORTANCE: Our objective was to study the diagnosis and management of this rare condition. A review of the literature concerning chondrosarcomas related to Maffucci's syndrome is reported. Cause and management are discussed. CLINICAL PRESENTATION: We report a case of Maffucci's syndrome associated with a cranial base chondrosarcoma. To our knowledge, only five similar cases have been reported in the literature. The differential diagnosis between Ollier's disease and Maffucci's syndrome and the causes of these conditions are not clear. INTERVENTION: An 18-year-old female patient presented with a giant tumor involving the posterior fossa, clivus, middle fossa, and cavernous sinus. The lesion could be totally removed through a transzygomatic approach. The histological diagnosis was chondrosarcoma. It was confirmed by immunohistochemical studies. There were no postoperative complications. CONCLUSION: Maffucci's syndrome is a rare clinical condition that presents difficulties concerning its diagnosis and management. It is characterized by the presence of multiple enchondromas and cutaneous hemangiomas. Intracranial chondrosarcomas may be associated with this syndrome. Immunohistochemical studies are necessary to differentiate chondrosarcomas from chordomas. The treatment of choice for cranial base chondrosarcomas is total removal of the lesion. Total removal may be very difficult to achieve because of the involvement of neurovascular structures. Alternative therapies, such as proton beam radiosurgery, should be considered. In this case, radical removal of the tumor was possible using a transzygomatic approach. Gross total removal of large cranial base chondrosarcomas is possible, but a longer follow-up period is necessary to ascertain that radical resection was achieved.

Arterial graft reconstruction in an aneurysm of the middle cerebral artery.

A case of a large aneurysm of the middle cerebral artery that was treated by resection of the aneurysm sac and reconstruction of the vessel is presented. The middle cerebral artery was reconstructed using a graft from the superficial temporal artery (STA). Cerebral vessel reconstructions are usually carried out with veins as grafts. This paper shows the possibility of using the STA as a graft. When a vessel reconstruction is contemplated, the skin flap should be planned in order to save the STA.

Esthesioneuroblastoma with intracranial extension.

The authors present five cases of olfactory neuroblastoma with intracranial extension operated on in the Department of Neurosurgery in collaboration with otorhinolaryngologists. This tumor is most frequently reported as growing inside the nasal cavities, and it can extend to the paranasal sinuses. Cases presenting initially as intracranial tumors have been infrequently reported. At present, histological diagnosis of this tumor is aided by the use of electron microscopy and immunocytochemistry. Total resection combined with radiation therapy remains the most satisfactory treatment.

Cystic cerebral cavernous angioma with dense calcification. Case report.

A case of cavernous angioma in the right temporoparieto-occipital area is reported. The unusually large area of calcification and cystic formation presented problems in preoperative diagnosis. The tumor was treated successfully by subtotal excision.

Cerebral cysticercosis presenting as mass lesion.

Four cases of cerebral cysticercosis that presented as brain tumor are reported. The diagnosis of these lesions was possible only after the operation. The clinical manifestations of these patients are discussed. The findings on computed tomography scanning as well as the possibilities for differential diagnosis are presented. All the patients were operated on and the diagnosis confirmed histologically. The difficulties encountered at the operations and the alternative methods for the treatment of these lesions are discussed.

[Delayed traumatic intracerebral hemorrhage. Report of 5 cases]. / Hemorrhagia intracerebral thraumática tardia. Registro de cinco casos.

Five cases of traumatic delayed intracerebral hemorrhage are reported. At the admission two patients showed only contusional injury and three had acute intracranial hematomas, one with an extradural infratentorial and two with supratentorial hematomas, which were immediately removed. Repeated CT-scans revealed the delayed intracerebral hemorrhage. Three patients developed an intracerebral hemorrhage within the first 24 hours after admission. The possible mechanisms producing these lesions are discussed. The high mortality of these patients (four in our series) is associated with severe brain damage after the traumatism.

Severe optochiasmatic arachnoiditis after rupture of an internal carotid artery aneurysm.

The case of a 24-year-old man with progressive visual loss due to optochiasmatic arachnoiditis is presented. The cause of the arachnoiditis was subarachnoidal bleeding due to rupture of an internal carotid artery aneurysm. The aneurysm was clipped 5 years after the first episode of bleeding. The diagnosis of optochiasmatic arachnoiditis was confirmed during the operation. This case is presented in order to discuss the causes, the symptoms and the therapeutical possibilities of this rare condition.

Brainstem cysticercosis simulating cystic tumor lesion. A case report.

The authors report the case of a 37 year-old man with a solitary cysticercus cyst in the brainstem (pons) successfully removed through a suboccipital craniectomy. Surgery in neurocysticercosis has been indicated in patients with hydrocephalus and/or large cystic lesions. Cystic lesions in the brainstem and spinal cord may have indication for surgery for two reasons: (1) diagnosis; and (2) treatment. Aspects related to differential diagnosis and therapeutic alternatives are discussed.

Chronic Aspergillus sp. meningitis successfully treated with fluconazole. Case report.

We a case of chronic Aspergillus sp. meningitis in a healthy 43-year-old woman successfully treated with fluconazole given orally (300 ms/day). The diagnosis was made by detection of anti-aspergillus antibodies and positive culture to Aspergillus sp. in the cerebrospinal fluid.

Pineal metastasis as first clinical manifestation of colorectal adenocarcinoma. Case report.

Cerebral metastases from colorectal adenocarcinomas occur in 8% of the cases. Diagnosis is usually made when primary disease and widespread metastases are already known. We report the case of a patient with single metastases in the pineal region as the first clinical manifestation of a colorectal adenocarcinoma. A 48-year-old female with Parinaud's syndrome for 15 days prior her admission was evaluated in our clinic. She had no symptoms or signs of colorectal disease. MRI examination revealed an heterogeneous lesion with peritumoral gadolinium enhancement, located in the pineal region. The tumor was radically resected through an infratentorial/supracerebellar approach. Histology showed metastatic carcinoma and immunohistochemical examination showed gastrointestinal tract adenocarcinoma. Metastases to the pineal region are extremely rare and should be considered in the differential diagnosis of tumors of this region.

[Choroid plexus carcinoma: report of 15 cases]. / Carcinoma de plexo coróide: relato de quinze casos.

Choroid plexus carcinoma (CPC) are rare central nervous system tumours derived from choroid plexus epithelium, affecting mainly children under 3 years of age. We present a clinical, epidemiological and histopathological study of 15 cases of CPC. Ten patients were male. Age ranged from 4 months to 21 years (mean=3,4). The lateral ventricles were affected in 73,3% of cases. Main symptom were: hydrocephalus (62.5%), intracranial hypertension (25%) and convulsion (12.5%). The patients were treated by surgery with partial resection in 75% of cases and total resection in 25%. There was one death due to surgical complication, 85.7% of patients had recurrence of tumours with mean survival rate of 13.6% months after diagnosis. Only one patient remain alive 5 years after initial treatment. These results support the poor prognosis and high mortality rate of CPC.

[Microsurgery of neurovascular decompression for trigeminal neuralgia: study of 35 cases]. / Microcirurgia de descompressão neuro-vascular para neuralgia do trigêmeo. Estudo de 35 casos.

The authors report the study of 35 cases of microvascular decompression for trigeminal neuralgia. No mortality and a very low morbidity were associated with this procedure. The choice of the treatment and the advantages of each method are discussed.

Surgical considerations about the anterior syphon knee of the internal carotid artery. An anatomical study.

An anatomical study about the anterior knee of the intracavernous carotid artery is presented. Twenty cavernous sinuses (CS) were dissected in cadavers using microsurgical techniques. A fibrous ring around the internal carotid artery (ICA) at the CS roof was found in all specimens. This fibrous attachment could be dissected from the surrounding dura and a loose connective tissue could be demonstrated around the ICA. This anatomical finding makes possible the microsurgical approach to vascular lesions of this portion of the ICA, without opening the cavernous sinus.

[Optic nerve gliomas: a study of 11 cases]. / Gliomas do nervo óptico: estudo de 11 casos.

Optic nerve gliomas may occur alone or as components of neurofibromatosis. They are rare tumors accounting for 2 to 5% of all intracranial tumors and 6% of the intra-orbitary neoplasms. The authors present 11 cases of optic nerve-glioma diagnosed in Curitiba in the last 25 years. Out of these 11 patients there were 10 women and only 1 man. The ages ranged from 3 to 25 years old, and 6 patients were under 15 years. In this series, 27.3% (n = 3) of the cases were associated with neurofibromatosis. Five patients had their tumors restricted to the optic nerve while the others had either extension to the optic chiasm, supra-selar region, frontal or temporal lobe. All the patients had pilocytic astrocytomas.