Preliminary Study on Application of Combined Monitoring of Neuroelectrophysiology-Intracranial Pressure-Cerebral Perfusion Pressure in Craniotomy for Intracranial Aneurysm Clipping: An Anatomical and Clinical Study

SUMMARY: Intracranial aneurysm is a common cerebrovascular disease with high mortality. Neurosurgical clipping for the treatment of intracranial aneurysms can easily lead to serious postoperative complications. Studies have shown that intraoperative monitoring of the degree of cerebral ischemia is extremely important to ensure the safety of operation and improve the prognosis of patients. Aim of this study was to probe the application value of combined monitoring of intraoperative neurophysiological monitoring (IONM)-intracranial pressure (ICP)-cerebral perfusion pressure (CPP) in craniotomy clipping of intracranial aneurysms. From January 2020 to December 2022, 126 patients in our hospital with intracranial aneurysms who underwent neurosurgical clipping were randomly divided into two groups. One group received IONM monitoring during neurosurgical clipping (control group, n=63), and the other group received IONM-ICP-CPP monitoring during neurosurgical clipping (monitoring group, n=63). The aneurysm clipping and new neurological deficits at 1 day after operation were compared between the two groups. Glasgow coma scale (GCS) score and national institutes of health stroke scale (NIHSS) score were compared before operation, at 1 day and 3 months after operation. Glasgow outcome scale (GOS) and modified Rankin scale (mRS) were compared at 3 months after operation. All aneurysms were clipped completely. Rate of new neurological deficit at 1 day after operation in monitoring group was 3.17 % (2/63), which was markedly lower than that in control group of 11.11 % (7/30) (P0.05). Combined monitoring of IONM-ICP-CPP can monitor the cerebral blood flow of patients in real time during neurosurgical clipping, according to the monitoring results, timely intervention measures can improve the consciousness state of patients in early postoperative period and reduce the occurrence of early postoperative neurological deficits.

El aneurisma intracraneal es una enfermedad cerebrovascular común con alta mortalidad. El clipaje neuroquirúrgico para el tratamiento de aneurismas intracraneales puede provocar complicaciones posoperatorias graves. Los estudios han demostrado que la monitorización intraoperatoria del grado de isquemia cerebral es extremadamente importante para garantizar la seguridad de la operación y mejorar el pronóstico de los pacientes. El objetivo de este estudio fue probar el valor de la aplicación de la monitorización combinada de la monitorización neurofisiológica intraoperatoria (IONM), la presión intracraneal (PIC) y la presión de perfusión cerebral (CPP) en el clipaje de craneotomía de aneurismas intracraneales. Desde enero de 2020 hasta diciembre de 2022, 126 pacientes de nuestro hospital con aneurismas intracraneales que se sometieron a clipaje neuroquirúrgico se dividieron aleatoriamente en dos grupos. Un grupo recibió monitorización IONM durante el clipaje neuroquirúrgico (grupo de control, n=63) y el otro grupo recibió monitorización IONM-ICP-CPP durante el clipaje neuroquirúrgico (grupo de monitorización, n=63). Se compararon entre los dos grupos el recorte del aneurisma y los nuevos déficits neurológicos un día después de la operación. La puntuación de la escala de coma de Glasgow (GCS) y la puntuación de la escala de accidentes cerebrovasculares de los institutos nacionales de salud (NIHSS) se compararon antes de la operación, 1 día y 3 meses después de la operación. La escala de resultados de Glasgow (GOS) y la escala de Rankin modificada (mRS) se compararon 3 meses después de la operación. Todos los aneurismas fueron cortados por completo. La tasa de nuevo déficit neurológico 1 día después de la operación en el grupo de seguimiento fue del 3,17 % (2/63), que fue notablemente inferior a la del grupo de control del 11,11 % (7/30) (P 0,05). La monitorización combinada de IONM-ICP-CPP puede controlar el flujo sanguíneo cerebral de los pacientes en tiempo real durante el corte neuroquirúrgico; de acuerdo con los resultados de la monitorización, las medidas de intervención oportunas pueden mejorar el estado de conciencia de los pacientes en el período postoperatorio temprano y reducir la aparición de problemas postoperatorios tempranos y déficits neurológicos.

Fisher Grading Scale and Cognitive Deficits ­ Literature Review

Subarachnoid hemorrhage (SAH) accounts for 5 to 10% of all types of stroke, with rupture of brain aneurysms being related to deficits in memory, executive functions, and language. Changes in brain functions appear to be related to the presence of blood in the subarachnoid space, and the Fisher Scale (FS) correlates the amount of blood identified on computed tomography (CT). This paper presents a literature review of the association of FS with cognitive deficits secondary to aneurysmal subarachnoid hemorrhage (aSAH), using PubMed. The attempt to correlate the amount of blood identified in the CT with the development of cognitive alterations presents conflicting data. It was evidenced that some of the studies did not perform cognitive tests, or did not show differences between the scores of FS due to sample difficulty. The FS, even with its limitations and imperfections, seems to be a safe and easily reproducible way to predict neurological, cognitive or neuropsychological deficits, in view of its routine use when analyzing patients with aSAH.

Bleeding risk of small intracranial aneurysms in a population treated in a reference center / Risco de sangramento de aneurismas intracranianos pequenos em uma população tratada em um centro de referência

ABSTRACT Large multicenter studies have shown that small intracranial aneurysms are associated with a minimal risk of bleeding. Nevertheless, other large series have shown that most ruptured aneurysms are, in fact, the smaller ones. In the present study, we questioned whether small aneurysms are indeed not dangerous. Methods: We enrolled 290 patients with newly-diagnosed aneurysms at our institution over a six-year period (43.7% ruptured). We performed multivariate analyses addressing epidemiological issues, cardiovascular diseases, and three angiographic parameters (largest aneurysm diameter, neck diameter and diameter of the nutrition vessel). Risk estimates were calculated using a logistic regression model. Aneurysm size parameters were stratified according to receiver operating characteristic (ROC) curves. Finally, we calculated odds ratios for rupture based on the ROC analysis. Results: The mean largest diameter for the ruptured versus unruptured groups was 13.3 ± 1.7 mm versus 22.2 ± 2.2 mm (p < 0.001). Multivariate analysis revealed a positive correlation between rupture and arterial hypertension (p < 0.001) and an inverse correlation with all three angiographic measurements (all p < 0.01). Aneurysms from the anterior cerebral artery bled more often (p < 0.05). According to the ROC curves, at the largest diameter of 15 mm, the sensitivity and specificity to predict rupture were 83% and 36%, respectively. Based on this stratification, we calculated the chance of rupture for aneurysms smaller than 15 mm as 46%, which dropped to 25% for larger aneurysms. Conclusion: In the population studied at our institution, small aneurysms were more prone to bleeding. Therefore, the need for intervention for small aneurysms should not be overlooked.

RESUMO Grandes estudos multicêntricos demostram que aneurismas intracranianos pequenos são associados a risco de sangramento mínimo. Outras grandes séries têm evidenciado que aneurismas rotos são em sua maioria os pequenos. Neste estudo questionamos até que ponto os aneurismas pequenos não são perigosos. Métodos: Avaliamos 290 novos casos de aneurismas tratados em nossa instituição durante 6 anos (43,7% rotos). Realizamos análises multivariadas com aspectos epidemiológicos dos pacientes, doenças cardiovasculares e três parâmetros angiográficos: maior diâmetro, diâmetro do colo e diâmetro do vaso nutridor do aneurisma. Estimativas de risco foram calculadas utilizando-se modelo de regressão logística. Parâmetros do tamanho aneurismático foram estratificados de acordo com curvas ROC. Também calculamos a razão de chances (odds ratios) de ruptura baseadas nas análises das curvas ROC. Resultados: O maior diâmetro médio para os grupos de aneurismas rotos e não-rotos foi 13.3 ± 1.7mm e 22.2 ± 2.2 (p < 0.001). Análises multivariadas revelaram uma correlação positiva entre ruptura aneurismática e hipertensão arterial (p < 0.001) e uma correlação inversa entre ruptura e as três medidas angiográficas (p < 0.01). Aneurismas da artéria cerebral anterior foram os que mais sangraram (p < 0.05). Análises das curvas ROC demonstram que no maior diâmetro de 15mm, a sensibilidade e especificidade para se predizer ruptura são de 83% e 36%. Baseando-se nessas estratificações, calculamos uma chance de ruptura para aneurismas menores de 15mm de 46% e de 25% para aneurismas maiores. Conclusão: Na população estudada, aneurismas pequenos são mais propensos a romper. Desta forma, a necessidade de intervenção para aneurismas pequenos não deve ser relevada.

Morphological distinguish of rupture status between sidewall and bifurcation cerebral aneurysms / Caracterización morfológica del estado de ruptura entre aneurismas cerebrales en paredes laterales y bifurcaciones

We suspect that morphological change of two types of aneurysms in ruptured and unruptured aneurysms are distinguishing because of different location and haemodynamics. So it is necessary to discuss sidewall and bifurcation type aneurysms in ruptured and unruptured state respectively. We used 209 consecutive aneurysms (144 ruptured, 65 bifurcation type) to assess the following parameters in 3D: maximum diameter (Dmax), maximum height (Hmax), aspect ratio (AR), size ratio (SR), height/width ratio (HW), bottleneck factor (BNF, width/neck) and inflow angle (IR). These aneurysms were divided into four groups by whether ruptured and sidewall or bifurcation. 4 groups were pairwise compared by univariate analysis and some parameters with significant variation were analyzed by multinomial logistic. Hmax (P=0.014) and HW (P=0.001) were different significantly between ruptured bifurcation and sidewall by multinomial logistic. There was no difference between unruptured bifurcation and sidewall (P>0.05) except for SR (P=0.002) by multinomial logistic. All data of ruptured aneurysms are different significantly from unruptured aneurysms (P<0.05) except for sidewall HW (P=0.414) by univariate analysis. But only SR (P < 0.001) and IR (P=0.006) of sidewall and SR (P=0.011) and HW (P=0.001) of bifurcation was significantly different by multinomial logistic. Volume of sidewall aneurysms are larger than bifurcation aneurysms and stretch characteristic of bifurcation is more obvious in ruptured aneurysms. Flow angle is the important criteria to predict fracture not in bifurcation aneurysms but in sidewall aneurysms. Size ratio is always a very important parameter to predict rupture of aneurysm no matter in bifurcation and sidewall type.

Sospechamos que el cambio morfológico de dos tipos de aneurismas, con y sin ruptura, son distinguibles por diferencias en su hemodinamia y ubicación. Por esto, es necesario discutir sobre el estado de ruptura en los aneurismas ubicados en una pared lateral o bifurcación, respectivamente. Utilizamos 209 aneurismas consecutivos (144 con ruptura y 65 de bifurcación) para evaluar los siguientes parámetros en tres dimensiones: diámetro máximo (Dmax), altura máxima (Amax), relación de aspecto (RA), relación de tamaño (RT), relación de altura/ancho (AA), factor de cuello de botella (FCB, ancho/cuello) y ángulo de entrada (AE). Los aneurismas se dividieron en cuatro grupos por su estado de ruptura (rotos y no rotos) y ubicación (pared lateral y bifurcación). Los grupos se compararon por pares mediante análisis univariado y quienes presentaran variación significativa fueron analizados por logística multinomial. La Amax (P=0,014) y AA (P=0,001) mostraron diferencias significativas entre aneurismas con ruptura en bifurcación y pared lateral, según la logística multinomial. No hubo diferencias entre los aneurismas sin ruptura en bifurcación y pared lateral (P>0,05), excepto para RT (P=0,002) por logística multinomial. Todos los datos de aneurismas con ruptura mostraron diferencias significativas con los sin ruptura (P<0,05), excepto para la AA en la pared lateral (P=0,414) según el análisis univariado. Sólo las RT (P<0,001) y AE (P=0,006) de la pared lateral, y RT (P=0,011) y AA (P=0,001) en bifurcación tuvieron diferencias significativas mediante logística multinomial. El volúmen de los aneurismas de pared lateral fue mayor que los de bifurcación, así como la ruptura fue más evidente en el tramo característico de la bifurcación. El AE es un criterio importante para predecir la rotura en los aneurismas de pared lateral. La RT siempre es un parámetro importante para predecir la rotura de un aneurisma, tanto para los que ocurren en bifurcación y en la pared lateral.

The Stent-Assisted Coil-Jailing Technique Facilitates Efficient Embolization of Tiny Cerebral Aneurysms

OBJECTIVE: Tiny cerebral aneurysms are difficult to embolize because the aneurysm's sac is too small for a single small coil, and coils within the aneurysm may escape from the confinement of a stent. This study was performed to introduce the stent-assisted coil-jailing technique and to investigate its effect on the coil embolization of tiny intracranial aneurysms. MATERIALS AND METHODS: Sixteen patients with tiny intracranial aneurysms treated with the stent-assisted coil-jailing technique between January 2011 and December 2013 were retrospectively reviewed and followed-up. RESULTS: All aneurysms were successfully treated with the coil-jailing technique, and at the end of embolization, complete occlusion of the aneurysm was achieved in 9 cases (56.3%), incomplete occlusion in 6 (37.5%), and partial occlusion in 1 (6.3%). Intraprocedural complications included acute thrombosis in one case (6.3%) and re-rupture in another (6.3%). Both complications were managed appropriately with no sequela. Follow-up was performed in all patients for 3-24 months (mean, 7.7 months) after embolization. Complete occlusion was sustained in the 9 aneurysms with initial complete occlusion, progressive thrombosis to complete occlusion occurred in the 6 aneurysms with initial near-complete occlusion, and one aneurysm resulted in progressive thrombosis to complete occlusion after initial partial occlusion. No migration of stents or coils occurred at follow-up as compared with their positions immediately after embolization. At follow-up, all patients had recovered with no sequela. CONCLUSION: The stent-assisted coil-jailing technique can be an efficient approach for tiny intracranial aneurysms, even though no definite conclusion regarding its safety can be drawn from the current data.

Number of coils necessary to treat cerebral aneurysms according to each size group: a study based on a series of 952 embolized aneurysms / Quantidade de molas necessárias para o tratamento endovascular dos aneurismas cerebrais de acordo com seu tamanho: estudo baseado em uma série de 952 aneurismas embolizados

OBJECTIVE: The Brazilian public health system determines a quantity of coils allowed to treat a cerebral aneurysm. The goal of this paper was to determine the number of coils necessary to treat an aneurysm based on size. METHODS: All patients harboring an aneurysm treated by endovascular approach between 1999 and 2003 were reviewed. RESULTS: There were 952 aneurysms included. Mean diameter sac was 8.2 mm with 7.9 coils per aneurysm. Out of 462 small aneurysms, mean size was 4.8 mm, with 4.6 coils/aneurysm used. A total of 315 medium aneurysms were treated, mean size was 8.6 mm, with 8.2 coils. Out of 135 large, mean size was 17 mm, with 16.1 coils. Forty giant aneurysms were treated with a mean size of 32 mm and 28.7 coils. CONCLUSIONS: We propose size as a reference to predict the number of coils necessary to treat each aneurysm: one coil for each millimeter of diameter.

OBJETIVO: O sistema público brasileiro determina uma quantidade limitada de molas permitida para o tratamento endovascular dos aneurismas cerebrais. O objetivo deste trabalho foi determinar a quantidade de molas necessária para tratar um aneurisma usando tamanho como referência. MÉTODO: Foram revisados todos os pacientes com aneurismas embolizados entre 1999 e 2003. RESULTADOS: No total, 952 aneurismas foram analisados. O diâmetro médio foi de 8,2 mm, com 7,9 molas usadas por aneurisma. Do total, 462 aneurismas eram pequenos, com tamanho médio de 4,8 mm e 4,6 molas/aneurisma. Foram tratados 315 aneurismas médios, com tamanho médio de 8,6 mm e 8,2 molas/aneurisma. Dentre os 135 aneurismas grandes, o tamanho foi de 17 mm, com 16,1 molas/aneurisma. Foram tratados 40 aneurismas gigantes, com média de 32 mm e 28,7 molas/aneurisma. CONCLUSÃO: Propomos que se utilize o tamanho do aneurisma como referência para prever o número de molas necessário para embolização: uma mola para cada milímetro de tamanho do saco aneurismático.

Artificial Luminal Narrowing on Contrast-Enhanced Magnetic Resonance Angiograms on an Occasion of Stent-Assisted Coiling of Intracranial Aneurysm: In Vitro Comparison Using Two Different Stents with Variable Imaging Parameters

OBJECTIVE: Intracranial stenting for stent-assisted coiling of aneurysms requires adequate follow-up imaging. The aim of this in vitro study was to compare in-stent artificial luminal narrowing on contrast-enhanced MR angiograms (CE-MRA) when applying Neuroform(R) and Enterprise(R) stents for stent-assisted coiling. MATERIALS AND METHODS: Two intracranial nitinol stents (Enterprise(R) and Neuroform(R)) were placed in silicon tubes and then imaged at 3 T and 1.5 T by the use of a T1-weighted three-dimensional spoiled gradient-echo sequence with minimal TR and TE. CE-MRAs were obtained by using different imaging planes, voxel sizes, and bandwidths, and with or without parallel imaging. Artificial lumen narrowing (ALN) was calculated and the results were compared. RESULTS: Lower magnetic field strength, axial plane perpendicular to axis of stent, and wider bandwidth resulted in a lower ALN on CE-MRA for both stents. Larger voxel size resulted in lower ALN for Neuroform(R) stent. The parallel imaging acceleration factor did not affect ALN. The mean ALN was lower for Neuroform(R), but it was not significant by a paired t test. CONCLUSION: CE-MRA of the stented lumen of vascular phantom was partially impaired with ALN. Consequently, image plane orientation, magnetic field strength, bandwidth, and voxel size should be adjusted appropriately to reduce ALN.

Aneurismas intracranianos gigantes: aspectos morfológicos, clínicos e operatórios / Intracranial aneurysms: morphological, clinical and operative aspects

Aneurismas intracranianos gigantes são definidos como aqueles em que o seu maior diâmetro ultrapassa 25 mm, sendo considerados entidade clínico-patológica que difere dos aneurismas de diâmetro menor quanto a incidência de ruptura, apresentação clínica e dificuldade de terapêutica. O tratamento do aneurisma gigante pode ser conservador, endovascular ou neurocirúrgico, e essa decisão depende de fatores como localização anatômica e características do aneurisma, condição médica, idade do doente, habilidades cirúrgicas e possibilidade de tratamento endovascular ou bypass. Apesar de o avanço no conhecimento da patogenia, hemodinâmica, morfologia, de a melhoria nos métodos de diagnóstico por imagem e de o desenvolvimento de técnicas endovasculares e microcirúrgicas terem possibilitado melhor resultado de tratamento, aneurismas gigantes apresentam prognóstico ruim e continuam desafiando os limites de técnicas neurocirúrgicas.

Intracranial giant aneurysms are defined as those larger than 2.5 cm in diameter. These aneurysms represent a clinicopathological entity that differs of ones smaller diameter regarding incidence of rupture, clinical presentation and therapeutic difficulties. The treatment of giant aneurysm can be conservative, endovascular or neurosurgical. This decision depends on factors such as anatomical localization and aneurysm characteristics, patient medical condition, age, surgical skills and possibility of endovascular tr eatment or bypas s. Be side s advancement of knowledge about pathogeny, hemodynamics, morphology, improvement of diagnostic imaging methods and development of endovascular and microsurgical techniques have improved the treatment outcome, giant aneurysms present bad prognosis and remain challenging the limits of neurosurgical techniques.

Ultra-Early Surgery for Poor-Grade Intracranial Aneurysmal Subarachnoid Hemorrhage: A Preliminary Study

PURPOSE: To describe the therapeutic effect and possibility of the ultra-early surgery for poor-grade aneurysmal subarachnoid hemorrhage (Hunt-Hess grades IV - V). MATERIALS AND METHODS: Nine cases with intracranial aneurysms, demonstrated by computed tomographic angiography (CTA), were treated by ultra-early surgery under general anesthesia within 24 hours from subarachnoid hemorrhage (SAH), 5 cases were treated within 6 hours and 4 cases in 6 - 24 hours. Preoperative Hunt-Hess grade: 6 cases were IV and 3 cases were V. The clinical outcome was evaluated by Glasgow Outcome Scores (GOS). RESULTS: In operation, difficult dissection occurred in 5 cases (55.6%), and rupture of aneurysm occurred and temporary obstructions were performed in 4 cases (44.4%). After clipping of aneurysm, 2 cases underwent V-P shunt because of hydrocephalus, pulmonary infection occurred in 3 cases, hypothalamus reaction accompanied with upper gastrointestinal hemorrhage in 2 cases. The clinical outcome were favorable (GOS 4 - 5) in 4 cases (44.4%), dissatisfied (GOS 2 - 3) in 3 cases (33.3%), and dead (GOS 1) in 2 cases (22.2%) when patients departed from our hospital. CONCLUSION: The ultra-early surgery can avoid early rebleeding of intracranial aneurysm, therefore, should be considered in the treatment of Hunt-Hess grade IV-V intracranial aneurysms. The appliance of CTA can make it possible to use of ultra-early surgery and improve the therapeutic effect.

Anomalies, aneurysm and histology of the middle cerebral artery in Nigerian Africans

The histology of the middle cerebral artery (MCA) in Nigerian Africans has not been previously studied. One hundred MCAs obtained at autopsy from fifty adult Nigerians were studied. The vessels were processed and stained with Ehrlich's haematoxylin and eosin, elastic Van Gieson and Masson's trichrome stains. Early branches were given off before the perforators in two middle cerebral arteries, and there was one accessory MCA, making an incidence of anomalies of 3 percent. No aneurysm was observed in any of the cases. The internal elastic laminas were well developed but the external elastic laminas of the vessels were poorly developed. Close to the bifurcations the tunica media tapered gradually and at the bifurcations, the tunica media was completely deficient being replaced by the tunica adventitia (Forbus raphé). The tunica adventitia was thicker at the bifurcations (0.21mm) compared to other sites of the vessel. The average thickness of the MCA tunica media at its origin was 0.12mm while that of the tunica adventitia was O.lOmm. These results are similar to what has been described in the literature for Caucasians. It buttresses the assertion that anatomical anomalies of the MCA are rare. The seemingly low frequency of MCA aneurysms in Nigerian Africans is not due to its anomalies or histology.

La histología de la arteria cerebral media (ACM) de los africanos de Nigeria no ha sido previamente estudiada. Fueron examinadas 100 ACM, obtenidas en autopsias de 50 individuos nigerianos adultos. Las arterias fueron procesadas y teñidas con hematoxilina y eosina de Ehrlich, Van Gieson para fibras elásticas y tricrómico de Masson. Ramas proximales se originan antes de la división en dos arterias cerebrales medias, y había una ACM accesoria, constituyendo una incidencia de anomalías del 3 por ciento. No se observó aneurisma en ninguno de los casos. La lámina elástica interna estaba bien desarrollada, pero la lámina elástica externa de los vasos estaba pobremente desarrollada. Cerca de la bifurcación la túnica media es gradualmente cónica, la túnica media es totalmente deficiente siendo sustituida por la túnica adventicia (Forbus raphé). La túnica adventicia es más gruesa en las bifurcaciones (0.21mm) en comparación con otros lugares del buque. El grosor medio de la túnica media de ACM en su origen fue 0.12mm mientras que el de la túnica adventicia de O.lOmm. Estos resultados son similares a los que han sido descritos en la literatura para Caucásicos. Es importante la afirmación que las anomalías anatómicas de la ACM son raras. La aparentemente baja frecuencia de los aneurismas de ACM en nigerianos africanos no es debido a sus anomalías o a la histología.

Etiopatogenia de los aneurismas cerebrales / Cerebral aneurysms etiopathogeny

En éste trabajo se hace una revisión de los conceptos más actuales y aceptados en relación a la formación, crecimiento, ruptura y reparación de los aneurismas cerebrales saculares, referidos frecuentemente en la literatura anglosajona como “berry aneurysms”, es decir, con forma de fresa o baya. Se revisan las hipótesis que explican el mecanismo de desarrollo de éstos aneurismas, debiendo existir un daño o defecto en la pared arterial, ya sea congénito, ligado a bases genéticas, o adquirido , relacionado con enfermedades desencadenantes de éste daño, o bien un defecto mixto congénito- adquirido, uniendo a lo anterior el factor de tensión hemodinámica que se ejerce sobre el citado defecto de la pared arterial. Se presentan las bases y explicaciones anatómicas de la etiopatogenia, y se reseñan las enfermedades con base genética que se relacionan con mayor frecuencia con la presencia de aneurismas cerebrales, así como también, se consideran las enfermedades que pudieran desencadenar un daño adquirido en la pared arterial, o producir alteraciones hemodinámicas que repercuten o impactan sobre la pared arterial dañada. Se reseña el mecanismo por el cual se puede llegar a la ruptura de la pared aneurismática, y las posibilidades comprobadas de reparación espontánea.

Spontaneous Dissecting Aneurysm of the Intracranial Vertebral Artery: Management Strategies

PURPOSE: Pathogenesis and treatment of spontaneous dissecting aneurysm of the intracranial vertebral artery (VA) remain controversial. This study was designed to provide management strategies and to improve management outcome in patients with these aneurysms. MATERIALA AND METHODS: Among a total of 1,990 patients treated for intracranial aneurysms from February 1992 to June 2005, 28 patients (1.4%) were treated either by surgery (8 patients) or neurointervention (20 patients) for spontaneous dissecting aneurysms of the intracranial VA. Twenty-two patients had ruptured aneurysms. We analyzed indications of surgery or neurointervention for each case, and assessed the management outcome at a 6-month follow-up. RESULTS: For selection of therapeutic options, patients were initially evaluated as possible candidates for neurointervention using the following criteria: 1) poor clinical grade; 2) advanced age; 3) medical illness; 4) unruptured aneurysm; 5) equal or larger opposite VA; 6) anticipated surgical difficulty due to a deep location of the VA-posterior inferior cerebellar artery (PICA) junction. Surgery was considered for patients with: 1) high-risk aneurysms (large or irregular shaped); 2) smaller opposite VA; 3) failed neurointervention; or 4) dissection involving the PICA. Management outcomes were favorable in 25 patients (89.3%). Causes of unfavorable outcome in the remaining 3 patients were the initial insult in 2 patients, and medical complications in one patient. CONCLUSION: Ruptured aneurysms must be treated to prevent rebleeding. For unruptured aneurysms, follow-up angiography would be necessary to detect growth of the aneurysm. Treatment modality should be selected according to the clinical characteristics of each patient and close collaboration between neurosurgeons and neurointerventionists is essential.

Experiencia con el tratamiento endovascular de los aneurismas del tope de la arteria basilar / Experience with the endovascular treatment of vasilar tip aneurysms

Objetivo. Describir los resultados inmediatos obtenidos en una serie de pacientes con aneurismas del tope de la arteria basilar tratados por vía endovascular en relación con el tamaño del cuello y saco del aneurisma, la presencia o no de ruptura aneurísmática y la gravedad clínica. Método. Se realizó un estudio descriptivo en una cohorte retrospectiva de 37 pacientes adultos de ambos sexos con aneurismas del tope de la arteria basilar tratados por vía endovascular (período 1993-2006). Los pacientes fueron clasificados con la escala de Hunt-Hess. Los aneurismas fueron clasificados según su tamaño y ancho del cuello. El grado de oclusión se clasificó en 4 categorías: A(100), B(>95), C(>90), D(<90). Resultados. En el 68 se logró una oclusión grado A y en el 1 se logró una oclusión grado B. La morbilidad fue del 7 en el subgrupo sin HSA y del 28 en el subgrupo con HSA. Se encontró una morbilidad del 9 en el grado HH 0; 12,5 en el grado HH 1-2; 58 en el grado HH 3 y 50 en el grado HH 4-5. La oclusión fue grado A en el 75 de los aneurismas con saco pequeño y cuello angosto y en el 55 de los aneurismas con saco grande y cuello ancho. La morbilidad global fue del 24 y la mortalidad global fue del 5,4. Conclusión. En base a los resultados descriptos la vía endovascular fue una buena alternativa para el tratamiento en agudo de los aneurismas rotos e incidentales del tope de la basilar, sobre todo cuando tenían un saco pequeño y cuello angosto y presentaban una menor gravedad clínica. Palabras clave: aneurisma cerebral, tope de basilar, tratamiento endovascular.

Objective. We describe the early results obtained in a series of cases with basilar tip aneurysms treated by endovascular surgery with detachable coils. The results are compared according to the size of the neck and the sac of the aneurysms, the history of aneurysms rupture and neurological state. Method: A retrospective descriptive study was made in a cohort of 37 adults patients of both sexes with basilar tip aneurysms treated by endovascular surgery (period 1993-2006). Hunt-Hess scale was usedfor patients classification. The aneurysms were classified according to their size and the wide of the neck. The occlusion grade was classified in 4 categories: A(100), B(>95), C(>90), D(<90). Results: Occlusion grade A was obtained un 68 of patients and occlusion grade B was obtained in 18 of patients. The morbidity was 7 in the non-SHA group and 28 in the SAH group. Morbidity was 9 in HH 0, 12,5 in grade HH 1-2, 58 in grade HH 3 and 50 in grade HH 4-5. Occlusion was grade A in 75 of the aneurysms with small sac and narrow neck and in 55 fo the aneurysms with a huge sac an broad neck. Global morbidity was 24 and global mortality was 5.4. Conclusion: According with our results, endovascular surgery was a good alternative for acute ruptured basilar tip aneurysms and incidental ones too, mainly when they had smaller sacs, narrower necks and a better neurological state. Key words: basilar tip aneurysm - cerebral aneurysm - endovascular treatment.

Ruptura de aneurisma intracraniano gigante em gestante tratado por embolização endovascular: relato de caso / Giant intracranial aneurysm rupture in pregnant woman treated by endovascular embolization: a case report

A ruptura de aneurismas intracranianos é causa rara de morbimortalidade na gravidez, havendo poucos relatos de tratamento endovascular na literatura. Documenta-se, neste relato, um caso de uma paciente de 37 anos de idade, no oitavo mês de amenorréia gestacional, apresentando quadro clínico e tomográfico compatível com hemorragia subaracnóidea (Hunt Hess III) por ruptura de aneurisma do segmento oftálmico da artéria carótida interna.

Intracranial aneurysm rupture is a rare cause of morbidity and mortality in pregnancy, with a few endovascular treatment cases reported in the literature. In this study we report a case of a 37-year-old woman in the eighth gestational month presenting tomographic findings and clinical manifestations compatible with subarachnoid hemorrhage (Hunt Hess III) due to rupture of an ophthalmic segment aneurysm in the internal carotid artery.

Aneurysm growth after brain tumor removal: case report

Um caso raro, em que ocorreu rápido aumento de volume de um aneurisma após a remoção de meningioma de fossa posterior em uma senhora de 69 anos de idade é relatado. Angiografias seriadas, tomografia computadorizada cerebral e ressonância magnética cerebral são apresentados. A paciente apresentava fatores de risco tanto para a formação como para o crescimento, de aneurismas cerebrais como hipertensão arterial, tabagismo, sexo feminino, aliados à redução da pressão intracraniana. É apresentada a evolução pós-operatória de um ano após a primeira cirurgia.

Aneurisma paraclinóideo: técnica cirúrgica e resultados em 51 pacientes / Paraclinoid aneurysms: surgical technique and results in 51 patients

Analisam-se 51 pacientes portadores de 55 aneurismas paraclinóideos (APC) submetidos a tratamento cirúrgico. Em decorrência de tratar-se de procedimento de alta complexidade, descrevemos em pormenor os seus aspectos técnicos. O processo clinóideo anterior foi removido por via extradural após secção da duplicação dural da tenda da fissura orbitária superior e/ou por via intradural. Conseguiu-se exclusão do APC nos 51 pacientes. Em dois casos a clipagem foi parcial e, em três, ocorreu oclusão da ACI. Em 42 (82 por cento) pacientes ocorreu bom resultado; em 5 (10 por cento), incapacidade moderada; em 1 (2 por cento), incapacidade grave e três (6 por cento) faleceram por infarto cerebral. Sete (13,7 por cento) pacientes tiveram lesão adicional do nervo óptico, sendo parcial em 4 (7,7 por cento) e total em 3 (6 por cento).

Bilobulated aneurysms at the origin of the posterior communicating artery

OBJECTIVE: The purpose of this paper is to describe the occurrence of bilobulated aneurysms at the origin of the posterior communicating artery. BACKGROUND: Bilobulated aneurysms at the origin of the posterior communicating artery from the internal carotid artery are rarely reported in the literature. A review of the literature showed only one report in which this type of aneurysm was addressed. METHODS: A consecutive series of 85 aneurysms operated by a single surgeon in 75 patients during an eight-year period (March 1995-February 2003) at the University Hospital was reviewed retrospectively. The incidence, radiological findings, intraoperative findings, surgical treatment and outcome of patients with bilobulated aneurysms at the origin of the posterior communicating artery were analyzed. The pathophysiologic mechanism for the formation of the bilobulated aneurysm was analyzed for each case. RESULTS: Thirty-two aneurysms (37.6%) located at the origin of the posterior communicating artery were operated. Four patients who had angiographic evidence of a bilobulated aneurysm at the origin of the posterior communicating artery were identified and operated. Among those four patients, only three had a bilobulated aneurysm. In one patient, microsurgical exploration revealed the presence of two consecutive aneurysms originating from the posterior communicating artery. The incidence of bilobulated aneurysms at the origin of the posterior communicating artery was 9.4%. One patient died during the postoperative period for a 25% mortality rate. CONCLUSIONS: The incidence of this type of aneurysm is low; therefore, they represent a technical challenge to the neurosurgeon.

Giant vertebrobasilar junction aneurysms: unusual cases.

Giant vertebrobasilar (VB) junction aneurysms are uncommon aneurysms, especially those associated with multiple aneurysms of the posterior circulation. We report two cases, one with a small and a giant aneurysm of the VB junction which were surgically clipped; and the other with a small left anterior inferior cerebellar artery (AICA) aneurysm which resolved spontaneously. The patient, however, developed a de-novo giant VB junction aneurysm, which was detected on a follow-up angiogram. This aneurysm was treated by surgical clipping. The clinical features, angiographic considerations and surgical treatment of such rare conditions are discussed and the relevant literature reviewed.

Distal calcarine fusiform aneurysm: a case report and review of literature.

A 50 year old female who was operated for atrial septal defect 8 years back, presented with clinical features suggestive of subarachnoid haemorrhage (grade I, Hunt and Hess). CT scan of brain revealed haemorrhage in all the supratentorial basal cisterns, sylvian cistern and small haematoma in the left occipital lobe. Conventional CT and MR angiography revealed aneurysm in relation to distal part of the calcarine branch of the left posterior cerebral artery (PCA). Left occipital craniotomy in prone position followed by deep dissection in the occipital lobe showed fusiform aneurysm of the distal part of the calcarine branch. PCA aneurysms constitute only 0.2 to 1% of all intracranial aneurysms and among them distal PCA aneurysms are most rare, constituting only 1.3%. They too are mostly seen at the bifurcation of the PCA. The present case however, is unique in the sense that it has developed as a fusiform aneurysm in the distal part of the calcarine branch. To the best of our knowledge this is rare among the rarest.