Transcallosal-Transchoroidal Approach for a Symptomatic Third Ventricular Cavernous Malformation in a Pediatric Patient: Surgical Video.

Cavernous malformations of the third ventricle are rare, deep-seated lesions that pose a formidable surgical challenge due to the rich, surrounding anatomy. Despite the potential morbidity of surgical treatment, the possibility of catastrophic, spontaneous hemorrhage in this location is even more feared and aggressive treatment is warranted, especially if the patient had suffered previous hemorrhages and is currently symptomatic. We demonstrate this approach (Video 1) on a 16-year-old boy who presented with right-sided hemiparesis (power grade 4), intense headaches, difficulties with learning and concentration, and memory loss, mainly affecting short-term memory. The patient had a previous unsuccessful excision at another center 3 months after initial hemorrhage. The absence of hydrocephalus and medial thalamic location favored a modified transcallosal transchoroidal (or subchoroidal) approach. Due to the anatomy of the lesion, no other microsurgical approaches were considered. The surgery at our center (second attempt) was performed 5 months after initial hemorrhage. The head was placed in neutral position, with a slight elevation of the vertex and the midline in a vertical position. A callosotomy had already been performed during the patient's first excision attempt at another center. Although dissection through the tela choroidea is commonly performed medially to the choroidal fissure when one wants to enter the third ventricle, we chose to carefully dissect through this structure laterally, because this thalamic lesion extended almost into the ependymal surface of the third ventricle. This way, the choroidal plexus became a protective cushion for the fornix. On entering the third ventricle, a mulberry-like lesion was readily identified and the cavernoma was located. The central contents of the cavernoma were dissected initially, causing relative deflation of the lesion and more maneuverability to dissect it away from the surrounding structures. Neuromonitoring was used to avoid brainstem injury. Postoperative magnetic resonance imaging showed complete resection with no signs of hemorrhage or ischemia. The patient was discharged on postoperative day 5 with no new neurologic deficits. The patient was also able to return to school after 1 month and showed complete recovery. Unfortunately, neuropsychologic evaluation was unavailable to understand his improvement better. Microsurgical dissection images in this video are a courtesy of the Rhoton Collection, American Association of Neurological Surgeons (AANS)/Neurosurgical Research and Education Foundation (NREF).

Proceso para la fusión de neuroimágenes de Tomografía por Emisión de Positrones y Resonancia Magnética / Process for the fusion of Positron Emission Tomography and Magnetic Resonance neuroimaging

En radiología se utilizan varias técnicas imagenológicas para el diagnóstico de enfermedades y la asistencia en intervenciones quirúrgicas con el objetivo de determinar la ubicación y dimensión exacta de un tumor cerebral. Técnicas como la Tomografía por Emisión de Positrones y la Resonancia Magnética permiten determinar la naturaleza maligna o benigna de un tumor cerebral y estudiar las estructuras del cerebro con neuroimágenes de alta resolución. Investigadores a nivel internacional han utilizado diferentes técnicas para la fusión de la Tomografía por Emisión de Positrones y Resonancia Magnética al permitir la observación de las características fisiológicas en correlación con las estructuras anatómicas. La presente investigación tiene como objetivo elaborar un proceso para la fusión de neuroimágenes de Tomografía por Emisión de Positrones y Resonancia Magnética. Para ello se definieron 5 actividades en el proceso y los algoritmos a utilizar en cada una, lo cual propició identificar los más eficientes para aumentar la calidad en el proceso de fusión. Como resultado se obtuvo un proceso de fusión de neuroimágenes basado en un esquema híbrido Wavelet y Curvelet que garantiza obtener imágenes fusionadas de alta calidad(AU)

In radiology, various imaging techniques are used for the diagnosis of diseases and assistance in surgical interventions with the aim of determining the exact location and dimension of a brain tumor. Techniques such as Positron Emission Tomography and Magnetic Resonance can determine the malignant or benign nature of a brain tumor and study brain structures with high-resolution neuroimaging. International researchers have used different techniques for the fusion of Positron Emission Tomography and Magnetic Resonance, allowing the observation of physiological characteristics in correlation with anatomical structures. The present research aims to develop a process for the fusion of neuroimaging of Positron Emission Tomography and Magnetic Resonance Imaging. Five activities were defined in the process and the algorithms to be used in each one, which led identifying the most efficient ones to increase the quality in the fusion process. As a result, a neuroimaging fusion process was obtained based on a hybrid Wavelet and Curvelet scheme that guarantees high quality merged images(AU)

Hypothalamic relapse of a cardiac large B-cell lymphoma presenting with memory loss, confabulation, alexia-agraphia, apathy, hypersomnia, appetite disturbances and diabetes insipidus.

A 37-year-old Hispanic man with a right atrial intracardiac mass diagnosed as diffuse large B-cell lymphoma (DLBCL) was successfully treated with surgery and chemotherapy. During 4 years, several total-body positron emission tomography and MRI scans showed no extracardiac lymphoma. On year 5 after the cardiac surgery, patient presented with sleepiness, hyperphagia, memory loss, confabulation, dementia and diabetes insipidus. Brain MRI showed a single hypothalamic recurrence of the original lymphoma that responded to high-dose methotrexate treatment. Correction of diabetes insipidus improved alertness but amnesia and cognitive deficits persisted, including incapacity to read and write. This case illustrates two unusual locations of DLBCL: primary cardiac lymphoma and hypothalamus. We emphasise the importance of third ventricle tumours as causing amnesia, confabulation, behavioural changes, alexia-agraphia, endocrine disorders and alterations of the circadian rhythm of wakefulness-sleep secondary to lesions of specific hypothalamic nuclei and disruption of hypothalamic-thalamic circuits.

Simultaneous meningioma and brain metastasis from renal cell carcinoma - a rare presentation. Case report.

CONTEXT:: Brain metastases are the most common tumors of the central nervous system. Because of their high frequency, they may be associated with rare situations. Among these are tumor-to-tumor metastasis and an even a rarer situation called simultaneous brain tumors, which are more related to primary tumors of the reproductive and endocrine systems. CASE REPORT:: A 56-year-old male patient with a history of renal cell carcinoma (which had previously been resected) presented with a ventricular lesion (suggestive of metastatic origin) and simultaneous olfactory groove lesion (probably a meningioma). First, only the ventricular lesion was dealt with, but after a year, the meningothelial lesion increased and an occipital lesion appeared. Therefore, both of these were resected in a single operation. All the procedures were performed by the same neurosurgeon. The patient evolved without neurological deficits during the postoperative period. After these two interventions, the patient remained well and was referred for adjuvant treatment. CONCLUSIONS:: This study provides the first description of an association between these two tumors. Brain metastases may be associated with several lesions, and rare presentations such as simultaneity with meningioma should alert neurosurgeons to provide the best oncological treatment.

Neuroblastoma with a solitary intraventricular brain metastasis visualized on I-123 MIBG scan.

BACKGROUND: Although metastatic skull lesions of neuroblastoma are not uncommon, brain involvement is infrequent and prompt diagnosis is of utmost importance in such cases. Previous studies have shown that Meta-Iodo-Benzyl-Guanidine (MIBG) scans were not always reliable in detecting central nervous system metastases, however most published reports referred to the Iodine-131 ((131)I)-MIBG scans. Herein, we report an intraventricular metastasis of neuroblastoma diagnosed using an Iodine-123 ((123)I)-MIBG scan, which is increasingly being used in clinical practice and reported as a more accurate method for detecting metastatic lesions. CASE DESCRIPTION: An unusual case of metastatic neuroblastoma to the left lateral ventricle of the brain is presented. Planar (123)I-MIBG scintigraphy showed faint tracer activity close to the midline without asymmetric extensions or abnormal activity in the skull bones. A subsequent brain MR scan revealed an enhancing mass within the left frontal horn consistent with a metastatic lesion. The patient underwent tumor resection with pathology showing neuroblastoma. CONCLUSIONS: Our case shows that (123) I-MIBG scintigraphy can be useful in detecting intraventricular brain metastases of neuroblastoma. Although the (123)I-MIBG scintigraphy has been reported to have a significantly superior sensitivity in monitoring asymptomatic patients with neuroblastoma compared with (131)I-MIBG scans, bone marrow histology, bone scan, CT, and urinary catecholamine levels, further studies may be necessary to evaluate its sensitivity in detecting brain lesions.

Supratentorial intraventricular solitary schwannoma. Case report and literature review.

OBJECTIVE: The objectives of this study were to present a case of a solitary intraventricular schwannoma with a review of the literature and to analyse the current theories of its origin. DESCRIPTION: A 16-year-old male patient, without any pathological, genetic or familial history of significance, presented with symptoms of intracranial hypertension and progressive left brachiocrural paresis. The magnetic resonance image showed a bulky intraventricular space-occupying lesion emerging from the posterior horn of the right lateral ventricle, with an irregular nodular component intimately connected to the choroid plexus, and a multiloculated cystic component extending beyond the ventricle. SURGICAL APPROACH: A right parietal craniotomy was performed, revealing a multiloculated cyst with xantochromic fluid and a soft brownish red nodule. The lesion was dissected surrounding the periphery and coagulating a vascular pedicle related to the wall of the right lateral ventricle and its choroid plexus. Total excision was achieved. The pathological exam reported an intraventricular schwannoma (WHO grade 1). The patient evolved favourably, with no recurrence at 36-month follow-up. CONCLUSION: The literature describes less than 45 cases of schwannomas not associated to cranial nerves of the following locations: intramedullary, leptomeningeal and only 12 intraventricular cases. The three theories explaining the origin of this last group describe: (1) a neoplastic transformation of peripheral nerve fibres, (2) a neoplastic transformation of autonomic neural tissue located within the intraventricular choroid plexus and (3) an abnormal embryogenesis leading to a failed migration of the neural crest cells. Complete resection is the therapeutic goal for this benign pathology to avoid recurrence.

[Subependymal nodules-sudependymal giant cell astrocytoma complex in children with tuberous sclerosis]. / Complejo nódulo subependimario-astrocitoma subependimario gigantocelular en niños con esclerosis tuberosa.

The object of this paper is to describe the imaging and clinical characteristics of subependymal nodule (SN) - subependymal giant cell astrocytoma (SGCA) complex in tuberous sclerosis and analyze its evolution in order to attempt early detection and the prevention of intracranial hypertension. We evaluated 22 patients with the pathological diagnosis of SGCA. The diagnosis was made at a median of 10.1 years old. We were able to observe the evolution of SN to ASGC: these SN were localized adjacent to the foramen of Monro and with time they underwent an important development with intense contrast enhancement and hydrocephalus. The acceleration in SN growth and its "transformation" into SGCA occurred at an average of 10 years of age, with a mean diameter of 9 mm. No SN located far from the foramen of Monro evolutioned to SGCA. Fifteen patients (68%) were operated with symptoms of intracranial hypertension. Average age at surgery was 10.8 years old. Six patients presented visual deficit and in these, the average diameter of the tumor was 31.5 mm, a high value when compared to 18.7 mm in the patients without visual deficit. The imaging and clinical follow-up of any subependymal lesion close to the foramen of Monro will permit, at a presymptomatic stage, an anticipation of surgical treatment thus reducing intracranial hypertension incidence. Prospective studies could determine whether the SN-SGCA complex corresponds to the same entity in distinct evolution stages or to two lesions with different growth potential.

Subependymal giant cell astrocytoma in children with tuberous sclerosis.

METHODS: Out of 105 patients with tuberous sclerosis (TS) admitted to the Hospital Nacional de Pediatría "Juan P. Garrahan" (Buenos Aires, Argentina), we surgically treated 17 children between January 1988 and December 2000. Two patients were operated on because of epilepsy and 15 patients because of an intraventricular tumor (subependymal giant cell astrocytoma [SGCA]). In this report we focus on tumors. Twelve of the 15 patients presented with hydrocephalus but none of them had a preoperative shunt. All tumors were surgically resected using frontal transventricular or transcallosal routes. Total removal was achieved in 12 out of 15 and subtotal removal in 3 out of 15 patients (resection of 70-95%). RESULTS: Exeresis of the tumor was not accompanied by significant morbidity and there was no perioperative mortality. Seizures and mental retardation did not improve after tumor resection. It was necessary to insert a postoperative shunt a long time after surgery in only one patient. There were no recurrences of SGCA that were totally removed after a mean follow-up of 51.7 months. CONCLUSIONS: We encourage surgery as soon as a lesion is diagnosed as a tumor. The "transformation" of subependymal nodules (SEN) into tumors (SGCA) may be considered controversial.

[Cavernoma of the lateral ventricle: case report]. / Cavernoma do ventrículo lateral: relato de caso.

UNLABELLED: Cavernous malformations are uncommon lesions that are usually present in the cerebral hemispheres. They occur rarely in the ventricular system, and even more rarely in the lateral ventricle. Only 28 cases have been previously reported in the literature. CASE: We present one case of lateral ventricle cavernoma in a 15-years-old female patient, who suffered of mild chronic headache for 8 months, followed by two episodes of sudden intensive headache and stupor with complete recovery after 48 hours. CT scan was performed and revealed a voluminous size, hiperdense mass in the frontal horn of the lateral ventricle. The surgical access to site was through transcallosal interhemisphere approach. The patient had a good recovery without complications. CONCLUSION: Although lateral ventricle cavernomas are rare they should be considered in the differential diagnosis of intraventricular tumors. A wrong preoperative diagnosis has sometimes induced a wrong therapy, such as radiotherapy, for these surgically curable benign lesions.

[Intraventricular neurocytoma. Report of 2 cases and analysis of the therapeutic possibilities]. / Neurocitoma intraventricular. Reporte de dos casos y análisis de posibilidades terapéuticas.

Intraventricular or central neurocytoma is a recently described unusual benign cerebral tumor. Common features include: predominant occurrence in young adults, septum pellucidum and fornix localization, and signs of intracranial hypertension due to obstructive hydrocephalus. Histopathologically, this tumor is characterized by a uniform neoplastic cell population with features of neuronal differentiation. Radiologic findings such as calcification, well-circumscribed tumor mass and confinement to the lateral and third ventricles are common. An anterior transcallosal neurosurgical approach yielded good outcomes. Radiotherapy should be considered for residual and recurrent neurocytomas. However, the radiation sensitivity of intraventricular neurocytoma has not been established and further studies are required to determine susceptibility to irradiation.

Factors predicting successful stereotactic aspiration of colloid cysts.

Stereotactic aspiration is a valuable surgical alternative for colloid cysts, but due to cyst heterogeneity, it is not uniformly successful as the sole treatment in all patients. Since 1981, we performed CT-guided stereotactic aspiration as the initial procedure in 25 patients with colloid cysts. We retrospectively reviewed our experience in the first 22 patients and found that preoperative CT imaging studies accurately determined size and predicted cyst viscosity. The preoperative CT appearance of a hypodense or isodense cyst correlated favorably with successful aspiration. Preoperative MRI provided excellent anatomic definition of the cyst and its relationship to other structures, but failed to correlate successful aspiration. Unsuccessful aspiration was related to the high viscosity of the intracystic material or deviation of the cyst away from the aspiration probe. These factors were used prospectively in 3 additional patients to accurately predict success of cyst aspiration.

Choroid plexus papillomas of the III ventricle in childhood. Their diagnosis and surgical management.

Ten infants and children with choroid plexus papilloma of the III ventricle are presented. Hydrocephalus of various degrees was present in all patients, and seven patients had bilateral ventriculoperitoneal shunts prior to craniotomy. All patients were investigated with computed tomography and angiography. Tumor was resected through the transfrontal-transventricular approach in nine and through a transcallosal approach in one. One patient died intraoperatively due to an uncontrollable hemorrhage from a subependymal vein at its point of entry into the homolateral internal cerebral vein, and another died shortly after surgery due to hypothalamic trauma. The remaining eight patients are alive without recurrence over a minimum follow-up period of 3 years; three have mental retardation and seizure disorder. Despite this tumor's deep location and vascularity and occurrence in infancy, choroid plexus papillomas of the III ventricle can be successfully resected. Appropriate care for hydrocephalus and intra- and postoperative management are important.

[Calcified papilloma of the choroid plexus. Report of a case]. / Papiloma calcificado do plexo coroide. Registro de um caso.

A case of calcified choroid plexus papilloma in a 7 years old child is reported. The radiologic findings are discussed.