Pablo Villanueva

Intracranial metastasis or meningioma? An uncommon clinical diagnostic dilemma.

BACKGROUND Cerebral metastases are the most frequent brain tumors in adults and they may occasionally present as an isolated meningeal mass, suggesting a meningioma. Because of the prognostic relevance in discriminating both tumors, we review the literature and analyze four patients in whom the diagnosis of meningioma was initially made. CASE DESCRIPTION Four cases of isolated meningeal metastases are presented and in all of them a meningioma was considered as the main preoperative diagnosis. Only one patient had a history of previous cancer. The primary tumors found after pathological testing of the lesions were thyroid carcinoma, prostate adenocarcinoma, breast adenocarcinoma, and hypernephroma. The clinical and neuroimaging features as well as the differential diagnoses are discussed. The literature regarding these forms of meningeal metastases was reviewed. CONCLUSIONS Although they are uncommon, dural metastases can be mistaken for meningiomas. Our experience in these cases has led us to consider ordinary metastases as a differential diagnosis even when a meningioma is suspected. The definitive diagnosis of a meningioma should be established only after the histopathological report has been analyzed.

Surgery for high-grade gliomas in a developing country: survival estimation using a simple stratification system

BACKGROUND In spite of great technological advances in diagnostic and therapeutic tools, survival in patients with HGG has not changed significantly in the last years. Judicious management in each case needs survival estimation after surgery. We used a simple stratification system evaluating the histology, patients age, and the KPS. METHODS We retrospectively made an analysis of survival in 103 patients with HGG operated in a 10-year period (1990--1999). Three significant prognostic variables were studied: histology, patients age, and KPS. The BS-MG was calculated, adding the partial score (0 or 1) obtained for each variable. This score ranges from 0 (worse condition) to 3 (best condition). RESULTS Overall, MS was 12 months. For glioblastoma multiforme, AA, and ODS, it was 10, 20, and 19 months, respectively (P = .0001). Patients 44 years old or younger had an MS of 28 months, higher than 10 months for patients older than 45 years (P < .0001). Median survival was 20 months for patients with KPS 80 or higher, and 9 months for those with KPS 70 or lower (P = .02). It was 3.5 months in patients with BS-MG = 0, 9 months for BS-MG = 1, 22 months for BS-MG = 2, and 55 months for BS-MG = 3 (P < .0001.). CONCLUSIONS Survival presented here is comparable with those previously reported despite lacking the most sophisticated surgical technique. The stratification score that includes the 3 most important variables for survival seems to be simple and reliable for survival estimation.

History of the Neurosurgery Department of Pontificia Universidad Catolica, Santiago, Chile

Pontificia Universidad Católica de Chiles medical school was founded in 1929. An interest in neurosurgical development arose in the minds of the Dean, Dr. Cristobal Espíldora, and the Chief of Surgery, Dr. Rodolfo Rencoret, in 1946. They encouraged and supported Dr. J. Ricardo Olivares to specialize in Neurosurgery with Professor H. Olivecrona in Stockholm, Sweden. The first neurosurgical procedure in the Hospital Clínico de la Universidad Católica was performed in 1950. Since then, intensive efforts have been made to develop neurosurgery and its science. As a result, it is now a center capable of achieving high-quality standards in vascular, oncologic, and endoscopic neurosurgery; stereotactic and radiosurgery; complex spine surgery; pediatric neurosurgery; and epilepsy surgery. This article tells the story of a university hospital neurosurgery service in a country at the southern end of the world and how it became one of the most important neurosurgical centers in Chile and South America.

Experiencia de un hospital universitario en el manejo de púrpura trombótico trombocitopénico-microangiopatía trombótica no inmune refractaria o en recaída tratado con rituximab: Report of eight cases

Thrombotic thrombocytopenic purpura, an immune/non-immune thrombotic microangiopathy (TTP/TMA) is associated with high morbidity and mortality, even with appropriate treatment. In patients refractory to standard treatment with plasmapheresis there is no certainty about the best therapeutic strategy. This report shows our experience in eight refractory patients who survived after treatment with rituximab.Thrombotic thrombocytopenic purpura, an immune / non-immune thrombotic microangiopathy (TTP / TMA) is associated with high morbidity and mortality, even with appropriate treatment. In patients refractory to standard treatment with plasmapheresis there is no certainty about the best therapeutic strategy. This report shows our experience in eight refractory patients who survived after treatment with rituximab.

Treatment of thrombotic thrombocytopenic purpura with rituximab

Thrombotic thrombocytopenic purpura, an immune/non-immune thrombotic microangiopathy (TTP/TMA) is associated with high morbidity and mortality, even with appropriate treatment. In patients refractory to standard treatment with plasmapheresis there is no certainty about the best therapeutic strategy. This report shows our experience in eight refractory patients who survived after treatment with rituximab.Thrombotic thrombocytopenic purpura, an immune / non-immune thrombotic microangiopathy (TTP / TMA) is associated with high morbidity and mortality, even with appropriate treatment. In patients refractory to standard treatment with plasmapheresis there is no certainty about the best therapeutic strategy. This report shows our experience in eight refractory patients who survived after treatment with rituximab.

Response and survival in acute myeloid leukemia patients not candidates to transplantation treated with azacitidine versus palliative treatment: a retrospective study

INTRODUCTION Acute myeloid leukemia has a high mortality if untreated. Hematopoietic stem cell transplantation is the only curative treatment so far. Patients who are not eligible to receive a transplant can be treated with hypomethylating agents that have shown to improve disease-free and overall survival. OBJECTIVE Retrospective description of the clinical characteristics of patients suffering from advanced myelodysplastic syndrome and acute myeloid leukemia that were treated with a hypomethylating agent as well as its adverse effects and response to treatment. METHODS This report shows our experience in 38 patients with acute myeloid leukemia treated with azacitidine or palliative treatment. RESULTS Azacitidine was able to prolong survival in 80% of patients with a high incidence of adverse effects and negative impact on quality of life. Most of the patients treated with palliative intent died in the first month after diagnosis. CONCLUSIONS Azacitidine can prolong survival but with significant adverse effects. Untreated patients had a high early mortality.

Endoscopic Endonasal Approaches for Benign Tumors Involving the Skull Base

With continued refinements in endoscopic image quality, instrumentation, surgical navigation, skull base closure techniques, anatomical understanding, and advanced neurosurgical and otolaryngological training, the endonasal endoscopic approach has become a well-accepted and widely utilized technique for the resection of most benign midline ventral skull base tumors. While pituitary adenomas and Rathke’s cleft cysts constitute the most common lesions removed via this route, increasing experience has led to its broader utilization for more complex lesions, including craniopharyngiomas, midline meningiomas, and schwannomas. In this article, we review the recent literature published on this topic with an emphasis on the most interesting and important new results and discoveries for each type of benign skull base tumor.

Resección de lesiones cerebrales con asistencia de mapeo cortical intraoperatorio

Introduction: Extensive resection for malignant intraaxial intracranial tumors has been demonstrated to improve survival. This is not always possible due to potential tumor location in or next to eloquent brain regions, like primary motor cortex or speech areas. In this case, avoiding neurological defi cits is challenging. One of the tools for minimizing that risk is intraoperative cortical mapping (ICM). This report describes the ICM technique of eloquent brain regions, feasibility and complementariness with other methods for tumor localization. Methods: Seven patients with brain lesions near eloquent regions operated on were analyzed. Frameless stereotaxis (neuronavigation) and intraoperative cortical mapping (direct cortical stimulation and monitoring of somatosensory evoked potentials) were used. The location, size, type of lesion, amount of resection, pre and postoperative neurological status were studied. Results: ICM was effective in localizing primary motor cortex in all patients. In 6 patients the tumor area without functionality was removed, achieving complete or greater than 90% resection in 5 of them. In one patient the lesion was a deep arteriovenous malformation located below the primary motor cortex. In this case ICM made feasible an approach from non-eloquent cortex to achieve total resection. No new postoperative defi cit was found in a 12 month follow-up period. Conclusion: ICM is useful and localize functional cortical regions effectively, simply and reliably, making possible to perform extensive tumor resections in eloquent regions. This technique is complementary to other tools for anatomical or physiological localization and could contribute to a safer and more effective surgery.

Importancia del drenaje venoso cortical en la historia natural de las fístulas durales

Dural arteriovenous fistulas are direct arteriovenous connections within the duramater either in the cranial or spinal region. They account for 10 to 15% of all intracranial arteriovenous malformations and they have been consistently reported since forty years. The clinical picture is variable with mild symptoms as tinnitus or secondary to ocular venous congestion, or severe ones, like neurologic symptoms or hemorrhage. They can present at any age but most of the patients are over 50 years old. The anatomy of this malformation is variable and sometimes difficult. Natural history is not completely known, therefore the best treatment is still a matter of debate. In order to achieve a favorable treatment, many publications have been focused in the classification of these malformations based on a relation between the anatomy and the natural history

Fístula arteriovenosa espinal: Case report and review

Se comunica un caso de Fistula arteriovenosa espinal dorsal. Se revisa la literatura en relacion al cuadro clinico, metodos diagnosticos y tratamiento. Se concluye que la terapia definitiva debe contemplar la oclusion de la vena. La cirugia parece tener mejor rendimiento a largo plazo. El pronostico es bueno, con mejoria o estabilizacion del cuadro clinico