Comparative analysis of aneurysm volume by different methods based on angiography and computed tomography angiography.

Endovascular treatment and prognosis of intracranial aneurysms are based on size and volume, which demand more accurate neuroimaging techniques. Aneurysm volume calculation is important to choose endovascular treatment modalities and packing density calculation. Of all these methods, it remains unknown which one is the most accurate to calculate aneurysm volume. The objective of this study is to compare the accuracy of three angiography-based versus three tomographic-based methods which calculate aneurysm volume. A retrospective study which included patients with ruptured and unruptured cerebral aneurysms diagnosed by angiogram and computed tomography angiography (CTA) was done. The accuracy of each method was assessed with an ellipsoid glass model of known volume, which helped us to adjust variation in volumetric measurements done with AngioSuite© and AngioCalc© softwares (based on angiographic and tomographic images), 3D-rotational angiography and 3D-CTA (tridimensional computed tomography angiography), based on measurements of diameters such as maximal width and maximal height. Descriptive statistics, ANOVA for repetitive samples and t test were used. We included 89 patients (126 saccular intracraneal aneurysms). AngioSuite© software (angiography-based) showed more accuracy compared to other methods in our control model. The geometric system (AngioCalc) based on CTA images was statistically different from all other methods studied. AngioCalc (CTA-based) demonstrated a significant difference compared with other methods hence, it may overestimate volume measurements. AngioSuite

[Melanocytoma and meningeal melanocytosis, similar but different lesions]. / Melanocitoma y melanomatosis meníngea, lesiones similares pero diferentes.

BACKGROUND: Meningeal melanomatosis is an extra-axial well-encapsulated malignant tumour with diffuse meningeal growth and dark coloration (due to high melanin contents), while meningeal melanocytoma is the focalized benign variant. Melanocytic lesions may be secondary to melanoma or be histologically benign, however, their diffuse nature makes them impossible to cure. Melanocytosis is a diffuse tumour that can form solitary extra-axial tumours, which invades the parenchyma and presents signs of malignancy with increased mitosis and Ki67, observed in 1 to 6% of immunopathological exams. Melanoma of the leptomeninges, presents signs of malignancy with anaplastic cells, which cluster in fascicles of melanin in the cytoplasm, with more than 3 atypical mitoses per field and Ki67 presenting in more than 6% of the immunopathological fields analysed. CLINICAL CASE: We present the case of a patient with long-term meningeal melanomatosis, with progressive neurologic deficit and characteristic radiologic features, and another case of meningeal melanocytoma. CONCLUSIONS: Benign melanocytic neoplasms of the central nervous system must be treated aggressively in the early phases with strict follow-up to avoid progression to advanced phases that do not respond to any treatment method. Unfortunately, the prognosis for malignant melanocytic lesions is very poor irrespective of the method of treatment given.

A proposed classification for assessing rupture risk in patients with intracranial arteriovenous malformations.

BACKGROUND: Whether cerebral arteriovenous malformations (AVMs) should be treated remains an ongoing debate. Nevertheless, there is a need for predictive factors that assist in labelling lesions as low or high risk for future rupture. Our aim was to design a new classification that would consider hemodynamic and anatomic factors in the rapid assessment of rupture risk in patients with AVMs. METHODS: This was a retrospective study that included 639 patients with ruptured and unruptured AVMs. We proposed a new classification score (1-4 points) for AVM rupture risk using three factors: feeding artery mean velocity (Vm), nidus size, and type of venous drainage. We employed descriptive statistics and logistic regression analysis. RESULTS: A total of 639 patients with cerebral AVMs, 388 (60%) had unruptured AVMs and 251 (40%) had ruptured AVMs. Logistic regression analysis revealed a significant effect of Vm, nidus size, and venous drainage type in accounting for the variability of rupture odds (P = 0.0001, R2 = 0.437) for patients with AVMs. Based in the odds ratios, grades 1 and 2 of the proposed classification were corresponded to low risk of hemorrhage, while grades 3 and 4 were associated with hemorrhage: 1 point OR = (0.107 95% CI; 0.061-0.188), 2 point OR = (0.227 95% CI; 0.153-0.338), 3 point OR = (3.292 95% CI; 2.325-4.661), and 4 point OR = (23.304 95% CI; 11.077-49.027). CONCLUSION: This classification is useful and easy to use, and it may allow for the individualisation of each cerebral AVM and the assessment of rupture risk based on a model of categorisation.

[Preoperative embolization with microspheres of giant supratentorial meningiomas: 5-year experience]. / Embolización preoperatoria con microesferas en meningiomas gigantes supratentoriales: experiencia de 5 años.

BACKGROUND: Preoperative embolization of hypervascular tumours such as meningiomas has proven to be a favorable factor for resection of the latter because it diminishes intraoperative bleeding and the need for blood transfusions. OBJECTIVES: Evaluation of surgical outcomes of preoperative embolization with microspheres of giant supratentorial meningiomas. METHODS: We retrospectively analyzed patient records from 2007 to 2012 with the diagnosis of giant supratentorial meningiomas (> 5 cm) (n= 27) and obtained two samples: those with preoperative embolization (n= 14) and patients without any properative embolization (n= 13). We evaluated and compared statistically significant surgical bleeding, surgical time and resection grade (via Simpson scale). Additionally, we evaluated internal/external vascularization rate and the histopathologic diagnosis. RESULTS: According to the Simpson scale, the mean resection grade was 1.21 for embolized meningiomas, whereas for non-embolized meningiomas it was 1.92 . No differences were found in surgical bleeding and operative time. We used microspheres whose diameters were 40-120 µm, and these were easily observed with common microscopy techniques. In all cases we observed predominance in extracranial vascularization. No morbidity and mortality were recorded with the endovascular procedure. CONCLUSIONS: Embolization with microspheres improves resection rate evaluated by the Simpson scale in patients with giant supratentorial meningiomas.

ANTECEDENTES: la embolización preoperatoria de tumores hipervascularizados, como los meningiomas, ha demostrado ser un factor favorable para su resección quirúrgica en términos de menor sangrado transquirúrgico y transfusiones sanguíneas. OBJETIVOS: evaluar el beneficio quirúrgico de la embolización preoperatoria con microesferas en meningiomas gigantes supratentoriales. MATERIAL Y MÉTODOS: estudio retrospectivo de los expedientes de pacientes postoperados entre 2007 y 2012 con diagnóstico de meningiomas gigantes supratentoriales (>5 cm) (n= 27). La muestra se dividió en dos grupos: pacientes embolizados antes de la intervención (n= 14), y pacientes a quienes no se realizó embolización (n= 13). Se comparó la cantidad de sangrado transoperatorio, el tiempo quirúrgico, y el grado de resección evaluado por la escala de Simpson. Además, se evaluó el tamaño tumoral, la tasa de vascularización de la carótida interna y externa y el diagnóstico histopatológico. RESULTADOS: el promedio de resección de acuerdo con la escala de Simpson para meningiomas embolizados fue de 1.21, mientras que para meningiomas no embolizados fue de 1.92 (t de Student, p= < 0.014). No encontramos diferencias significativas en tiempo quirúrgico o en el sangrado transoperatorio. En más de la mitad de los casos utilizamos microesferas de 40-120 µm de diámetro. Las microesferas se observaron fácilmente con los métodos usuales de microscopia y tinción, su existencia se correlacionó con áreas focales de necrosis. En todos los casos se encontró predominio de vascularización extracraneal, sin que el procedimiento endovascular se asociara con mortalidad. CONCLUSIONES: la embolización de meningiomas gigantes supratentoriales con microesferas mejora el grado de resección quirúrgica evaluada por la escala de Simpson.