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Videos by Edgar Nathal
This video shows the case of a giant thrombosed middle cerebral artery aneurysm, treated through ... more This video shows the case of a giant thrombosed middle cerebral artery aneurysm, treated through proximal occlusion and STA-MCA bypass. The aneurysm presented as a mass effect causing cerebral right side symptoms. The giant aneurysm mass was removed and the symptoms disappeared. This technique protects the distal circulation and preserves the viability of the brain tissue.
1 views
This video describes the surgical technique to reconstruct the right A2 segment because the prese... more This video describes the surgical technique to reconstruct the right A2 segment because the presence of a partially thrombosed aneurysm.
1 views
This video shows the revascularization technique for treatment of Moyamoya disease using a by pas... more This video shows the revascularization technique for treatment of Moyamoya disease using a by pass from the superficial temporal artery (STA) to a branch of the middle cerebral artery (MCA), in a patient with recurrent transitory ischemic attacks (TIA´s). After the bypass, the ischemic events dissapeared. Revascularization is used as a treatment for Moyamoya disease that is characterized for a progressive occlusion of the internal carotid artery (ICA) and its terminal branches.
2 views
Papers by Edgar Nathal
Journal of Cerebrovascular and Endovascular Neurosurgery, Nov 23, 2023
Acta Neurochirurgica
Background Paraclinoid aneurysms represent a challenge for neurosurgeons due to the anatomical co... more Background Paraclinoid aneurysms represent a challenge for neurosurgeons due to the anatomical complexity of this region. Then, innovative techniques such as the extradural sphenoid ridge approach are suitable for a safe microsurgical clipping. Method A description of the surgical technique was made by the senior author, a vascular neurosurgeon experienced with the use of this approach in the management of paraclinoid aneurysms exemplified through a clinical case. Conclusion Microsurgical clipping through an extradural sphenoid ridge keyhole approach for small and midsize paraclinoid aneurysms is an excellent treatment modality with good clinical and surgical results.
Objective To investigate the strategy of direct surgical treatment for paraclinoid aneurysms. Met... more Objective To investigate the strategy of direct surgical treatment for paraclinoid aneurysms. Methods Clinical data of 21 cases of paraclinoid aneurysms having
Surgical Neurology, Nov 1, 2007
The arachnoid knife is a useful instrument when performing a variety of neurosurgical procedures,... more The arachnoid knife is a useful instrument when performing a variety of neurosurgical procedures, for example, while opening the sylvian fissure or basal arachnoid bridges in the pterional approach or during the peripheral delimitation and excision of a cortical AVM. At present, there exists a wide variety of arachnoid knives made from different materials (stainless steel, titanium, or diamond-tipped); however, most of these instruments are expensive and may become dull with continuous use or bad handling. In this article, we report the use and advantages of an arachnoid knife from a simple hypodermic needle. In the last 6 years, we have used this technique to open the arachnoid layer in more than 350 neurosurgical procedures. Furthermore, it can be used to perform sharp arteriotomies during bypass procedures or to open the dura mater over bone structures. To date, no complication arising from this simple technique has been documented. A standard hypodermic needle can be used in the operating room as a practical arachnoid knife. It has the characteristics of being effective, low-cost, and available worldwide.
Acta neurochirurgica, Sep 1, 1992
We reviewed the surgical outcome in 85 patients with ruptured anterior communicating artery (ACoA... more We reviewed the surgical outcome in 85 patients with ruptured anterior communicating artery (ACoA) aneurysms, who were operated on within 72 hours of onset via a basal interhemispheric (BIH) approach (Group 1, N = 48), or an anterior interhemispheric (AIH) approach (Group 2, N = 37). The age, sex ratio and pre-operative grade (Gr) were similar for both groups. The outcome at the time of discharge was as follows for group 1: excellent or good 88%; fair, 6%; vegetative state, 2% and death 4%. For group 2, it was: excellent or good 78%; fair, 16%; vegetative state, 3%; and death, 3%. A significant correlation between admission grade and outcome was found in both groups. The outcome in group I was better than in group 2 for patients with a Glasgow Outcome Scale (GOS) better than fair (p < 0.07). No patient in group 1 had postoperative anosmia, but nine patients in group 2 became anosmic. The total number of complications was also significantly less in group 1. Our overall mortality rate was 4%. In conclusion, the BIH approach was more beneficial for treating acute ACoA aneurysm.
World Neurosurgery, Mar 1, 2018
Brainstem cavernous malformations (BSCM) account for up to 15% of all intracranial cavernous malf... more Brainstem cavernous malformations (BSCM) account for up to 15% of all intracranial cavernous malformations. Due to their complex anatomical location, they represent a significant challenge for neurosurgeon. As such, the identification of risk factors associated with negative outcomes is of significant importance. We analyze a series of 50 cases of BSCMs treated surgically in order to identify risk factors for unfavorable outcomes. Methods: Patients who underwent surgical resection of BSCM at our institution between 2000 and 2015 were retrospectively reviewed. Univariate and multivariable logistic regression models were used to identify predictors of unfavorable outcomes, defined as those with a modified Rankin score (mRs) of greater than 2. Results: 50 Latin American patients, with a mean age of 35.85±13.06 years, consisting of 29 females (58%) and 21 males (42%) underwent surgical resection. Mean Modified Rankin Scale (mRs) score at admission was 2.6±1.05 and the mean BCSM size was 18.00±7.19 mm. The rate of gross total resection was 92%. Overall, 80% of patients showed improved or unchanged clinical status at the last follow-up period, however only 58% of patients had a favorable outcome with a mean mRs of 2.33±1.136. Multivariable logistic binary regression identified hemorrhagic recurrence (P=0.040), lower cranial nerve deficit (P=0.019), and BSCMs greater than 15 mm in diameter (P=0.006) as predictive factors for unfavorable surgical outcomes. Conclusion: BSCM size, compromise of lower cranial nerves, and hemorrhagic recurrence before surgery were identified as risk factors associated with unfavorable outcomes of surgically treated BSCMs in this cohort.
Journal of Neurosurgery, Apr 1, 1992
v" The intraoperative anatomical findings of the anterior communicating artery (ACoA) complex in ... more v" The intraoperative anatomical findings of the anterior communicating artery (ACoA) complex in 46 patients with anatomical variations were compared to those in an equal number of patients without variations in order to determine the visualization of the elements of the vascular complex. All patients underwent radical surgery for an ACoA aneurysm by one of three different surgical approaches: transsylvian, anterior interhemispheric, or basal interhemispheric. Visualization of the vascular elements was similar in patients with or without anatomical variations. The differences observed were dependent on the surgical approach selected and on the projection of the aneurysm. It was found that, even when the intraoperative anatomical field and the number of vascular elements visualized are different from those obtained in autopsy studies, the vascular microanatomical characteristics can be confirmed with each surgical approach to the extent necessary to ensure safe clipping ofaneurysms in patients both with and without anatomical variations.
ABSTRACT Effective treatment of cerebral vasospasm is still a matter of concern in clinical neuro... more ABSTRACT Effective treatment of cerebral vasospasm is still a matter of concern in clinical neurosurgery. In refractory cases, the use of intraarterial vasodilators as papaverin or even mechanical angioplasty has been recommended. Experience with intraarterial nimodipine has been seldom reported. From March to November 2004, 23 patients underwent what we define as “chemical angioplasty,” using repeated doses of intraarterial nimodipine for treating refractory vasospasm to other therapeutic modalities. A microcatheter was positioned in the internal carotid artery or the vertebrobasilar system as close as possible to the spastic area. A single 200 mg injection was completed each time until circulation improved or a 1200 mg dose perday was reached. All patients were evaluated using the modified 6-point Rankin scale after the procedure and during neurological follow up. The chemical angioplasty was repeated daily until the vasospasm period was surpassed or there was a failure of the technique and low-density areas (LDA) on the CT scan appeared. The response to this treatment was considered good in seventeen patients (symptomatic vasospasm disappeared with improvement on the Rankin scale), regular in three (symptomatic vasospasm without low-density areas on CT scan), and bad in three (appearance of lowdensity areas on CT scan). It was demonstrated that intraarterial nimodipine decreases the transit time in angiography and improves the cerebral blood volume in the MRI-perfusion sequence without a significant change in the mean transit time. “Chemical” angioplasty with nimodipine can be used repeatedly in some patients with severe vasospasm to prevent the appearance of lowdensity areas on CT scan before mechanical angioplasty is considered.
Neurologia Medico-chirurgica, 1992
A rare case of bilateral abducens nerve paralyses after rupture of an anterior communicating arte... more A rare case of bilateral abducens nerve paralyses after rupture of an anterior communicating artery (AcoA) aneurysm occurred in a 56-year-old female after sudden onset of severe headache. Bilateral ab ducens nerve paralyses were present without additional neuro-ophthalmological signs. Computed tomography revealed subarachnoid hemorrhage (SAH). Angiography showed an AcoA aneurysm (15 mm in diameter, directed anteroinferiorly) that was successfully clipped. Postoperatively, the bilateral abducens nerve paralyses gradually recovered and disappeared 3 months after onset. Bilateral ab ducens nerve paralyses may occur after SAH due to ruptured AcoA aneurysm, and neurosurgeons should be alert to this possibility.
Introduccion. Los aneurismas del tope de la arteria basilar representan cerca del 50% de los aneu... more Introduccion. Los aneurismas del tope de la arteria basilar representan cerca del 50% de los aneurismas de la circulacion posterior. En la actualidad a pesar de los avances en el tratamiento endovascular, los indices de recanalizacion permanecen altos, con mayor riesgo de resangrado a largo plazo. Material y Metodos. Se realizo un estudio retrospectivo de una base de datos llevada de forma prospectiva de todos los aneurismas de la bifurcacion basilar operados en el Instituto Nacional de Neurologia “Manuel Velasco Suarez” de la Ciudad de Mexico en el periodo de 1997-2019. Se analizo la informacion demogra- fica y los resultados quirurgicos. Ademas, se revisaron los aspectos anatomicos basicos y los principales abordajes empleados para tratar estos aneurismas. Resultados. Los aneurismas del tope de la basilar representaron el 1.73% de un total de 1670 aneurismas operados y el 47.5% de los aneurismas de la circulacion posterior (29 casos). Fueron mas frecuentes en el sexo femenino con una relacion 1.2:1. La edad promedio fue de 49.3 anos (rango 22-70 anos). Solo se operaron pacientes con grado neurologico 1-3 de Hunt y Kosnik. La mayor parte fueron aneurismas menores de 10 mm. El 75.8% (n=22) de los casos se originaron en una bifurcacion en posicion normal. Se observo una asociacion con aneurismas multiples en el 37.9% de los casos. La mayor parte (55.1%) presentaron un domo con direccion superior y el 20% fueronaneurismas grandes o gigantes. El abordaje mas utilizado fue el pterional pretemporal. El indice de oclusion total fue del 82.7%. En el seguimiento a 6 meses, 25 pacientes (86%) tuvieron una puntuacion de 0-2 en la escalamodificada de Rankin. La mortalidad global fue del 6.8%. Los resultados mas pobres se obtuvieron en pacientes con aneurismas gigantes y en aquellos que desarrollaron vasoespasmo sintomatico. Conclusiones. La microcirugia ofrece una opcion viable de tratamiento para aneurismas del tope de la basilar. Cuando se tratan en centros de referencia se obtienen resultados quirurgicos muy aceptables e indices de oclusion mayoral obtenido por terapia endovascular.
Stroke, Feb 1, 2016
Brainstem cavernous malformation (BCM) account for 8-22% of all intracranial cavernomas. Currentl... more Brainstem cavernous malformation (BCM) account for 8-22% of all intracranial cavernomas. Currently, they can be treated microsurgically or conservative but it is still difficult to choose the best treatment for each patient. The main objective of our series was to evaluate the long-term functional outcome and recurrence in patients with BCM treated with conservative or surgical treatments. Hypothesis: We assessed the hypothesis that surgical and conservative treatments are associated with different functional outcome and re-hemorrhage rate in long-term follow-up. Methods: In this non-randomized, clinical series, we compared the clinical and radiological findings of patients with their first hemorrhage secondary to confirmed BCM, treated in a tertiary neurological center, during a twenty five- year period. Treatment of each patient was selected by the attending physician and consisted of either conservative or surgical evacuation of BCM. The primary end-points were recurrent hemorrhage and functional outcome. Favorable prognosis was defined as modified Rankin scale (mRs) of 0 to 2. Results: From January of 1990 to July of 2015; 99 patients with BCM hemorrhage were treated (59 [59,6%] female; mean age 37± 13 years). 37 patients (37,4%) were surgically treated and 62 (62,6%) received conservative treatment. During the follow-up; 20 patients in the medical group (median time of recurrence: 34,5 months; IQR: 13,75-93) and 4 patients in the surgical group (median time of recurrence: 22 months; IQR: 9-46,5) had a recurrence (OR: 0,255; 95% IC: 0,079-0,817), with a cumulative incidence of 5,1 per 100 years-person and 3,96 per 100 years-person respectively. Because of rebleeding, 11 patients of the conservative group were taken to surgery and 3 of the surgical group were to required re-intervention. At the end of follow-up (median: 51 months; IQR: 19-104) 51 patients remained in the conservative group and 28 (54,9%) had a favorable mRs. 48 patients remained in the surgical group and 27 (56,2%) had a favorable mRs (OR:0,94 95% IC: 0,42-2,09). Conclusion: Despite a significant high recurrent hemorrhage rate was observed in conservative treated patients, we did not found difference in clinical outcome between both groups of patients with BCM.
PubMed, Mar 1, 1993
Ischemic cerebrovascular disease is an important cause of morbidity and mortality. One common fin... more Ischemic cerebrovascular disease is an important cause of morbidity and mortality. One common final pathway in neuronal ischemic damage is the uncontrolled influx of calcium into the cell, mediated by voltage dependent channels or activation of the NMDA (N-methyl D-aspartate) receptor. The therapeutic utility of a non-competitive NMDA blocker (MK-801, 2 mg/kg i.p.), to prevent the neuronal ischemic damage in an experimental middle cerebral artery occlusion model has been tested. The drug was administered 10 minutes before (group 3) and one hour after the arterial occlusion (group 4), and the results were compared with a group in which no medicament was utilized (group 2) and a control group (sham operation, group 1). MK-801 reduced significantly the area of infarction in relation to the control group (p < 0.05), mainly if the MK-801 was administered before the occlusion (group 3). These results suggest that MK-801 may be useful for the prevention of the neuronal ischemic damage caused by focal ischemia. However, before recommending its use in humans, all the possible collateral effects must be defined.
Archivos de neurociencias (México, D.F.), Mar 1, 2005
In this paper, is presented the case of a 32-year-old, righ-handed male patient, with a clinical ... more In this paper, is presented the case of a 32-year-old, righ-handed male patient, with a clinical picture characterized by facial pain and diplopia 12 months before admission. The patient was then a worker in the United States of America and received medical attention there. After performing a CT sean, no definite diagnosis could be established. The patient returned to Mexico
Archivos de neurociencias, 2006
This video shows the case of a giant thrombosed middle cerebral artery aneurysm, treated through ... more This video shows the case of a giant thrombosed middle cerebral artery aneurysm, treated through proximal occlusion and STA-MCA bypass. The aneurysm presented as a mass effect causing cerebral right side symptoms. The giant aneurysm mass was removed and the symptoms disappeared. This technique protects the distal circulation and preserves the viability of the brain tissue.
1 views
This video describes the surgical technique to reconstruct the right A2 segment because the prese... more This video describes the surgical technique to reconstruct the right A2 segment because the presence of a partially thrombosed aneurysm.
1 views
This video shows the revascularization technique for treatment of Moyamoya disease using a by pas... more This video shows the revascularization technique for treatment of Moyamoya disease using a by pass from the superficial temporal artery (STA) to a branch of the middle cerebral artery (MCA), in a patient with recurrent transitory ischemic attacks (TIA´s). After the bypass, the ischemic events dissapeared. Revascularization is used as a treatment for Moyamoya disease that is characterized for a progressive occlusion of the internal carotid artery (ICA) and its terminal branches.
2 views
Journal of Cerebrovascular and Endovascular Neurosurgery, Nov 23, 2023
Acta Neurochirurgica
Background Paraclinoid aneurysms represent a challenge for neurosurgeons due to the anatomical co... more Background Paraclinoid aneurysms represent a challenge for neurosurgeons due to the anatomical complexity of this region. Then, innovative techniques such as the extradural sphenoid ridge approach are suitable for a safe microsurgical clipping. Method A description of the surgical technique was made by the senior author, a vascular neurosurgeon experienced with the use of this approach in the management of paraclinoid aneurysms exemplified through a clinical case. Conclusion Microsurgical clipping through an extradural sphenoid ridge keyhole approach for small and midsize paraclinoid aneurysms is an excellent treatment modality with good clinical and surgical results.
Objective To investigate the strategy of direct surgical treatment for paraclinoid aneurysms. Met... more Objective To investigate the strategy of direct surgical treatment for paraclinoid aneurysms. Methods Clinical data of 21 cases of paraclinoid aneurysms having
Surgical Neurology, Nov 1, 2007
The arachnoid knife is a useful instrument when performing a variety of neurosurgical procedures,... more The arachnoid knife is a useful instrument when performing a variety of neurosurgical procedures, for example, while opening the sylvian fissure or basal arachnoid bridges in the pterional approach or during the peripheral delimitation and excision of a cortical AVM. At present, there exists a wide variety of arachnoid knives made from different materials (stainless steel, titanium, or diamond-tipped); however, most of these instruments are expensive and may become dull with continuous use or bad handling. In this article, we report the use and advantages of an arachnoid knife from a simple hypodermic needle. In the last 6 years, we have used this technique to open the arachnoid layer in more than 350 neurosurgical procedures. Furthermore, it can be used to perform sharp arteriotomies during bypass procedures or to open the dura mater over bone structures. To date, no complication arising from this simple technique has been documented. A standard hypodermic needle can be used in the operating room as a practical arachnoid knife. It has the characteristics of being effective, low-cost, and available worldwide.
Acta neurochirurgica, Sep 1, 1992
We reviewed the surgical outcome in 85 patients with ruptured anterior communicating artery (ACoA... more We reviewed the surgical outcome in 85 patients with ruptured anterior communicating artery (ACoA) aneurysms, who were operated on within 72 hours of onset via a basal interhemispheric (BIH) approach (Group 1, N = 48), or an anterior interhemispheric (AIH) approach (Group 2, N = 37). The age, sex ratio and pre-operative grade (Gr) were similar for both groups. The outcome at the time of discharge was as follows for group 1: excellent or good 88%; fair, 6%; vegetative state, 2% and death 4%. For group 2, it was: excellent or good 78%; fair, 16%; vegetative state, 3%; and death, 3%. A significant correlation between admission grade and outcome was found in both groups. The outcome in group I was better than in group 2 for patients with a Glasgow Outcome Scale (GOS) better than fair (p < 0.07). No patient in group 1 had postoperative anosmia, but nine patients in group 2 became anosmic. The total number of complications was also significantly less in group 1. Our overall mortality rate was 4%. In conclusion, the BIH approach was more beneficial for treating acute ACoA aneurysm.
World Neurosurgery, Mar 1, 2018
Brainstem cavernous malformations (BSCM) account for up to 15% of all intracranial cavernous malf... more Brainstem cavernous malformations (BSCM) account for up to 15% of all intracranial cavernous malformations. Due to their complex anatomical location, they represent a significant challenge for neurosurgeon. As such, the identification of risk factors associated with negative outcomes is of significant importance. We analyze a series of 50 cases of BSCMs treated surgically in order to identify risk factors for unfavorable outcomes. Methods: Patients who underwent surgical resection of BSCM at our institution between 2000 and 2015 were retrospectively reviewed. Univariate and multivariable logistic regression models were used to identify predictors of unfavorable outcomes, defined as those with a modified Rankin score (mRs) of greater than 2. Results: 50 Latin American patients, with a mean age of 35.85±13.06 years, consisting of 29 females (58%) and 21 males (42%) underwent surgical resection. Mean Modified Rankin Scale (mRs) score at admission was 2.6±1.05 and the mean BCSM size was 18.00±7.19 mm. The rate of gross total resection was 92%. Overall, 80% of patients showed improved or unchanged clinical status at the last follow-up period, however only 58% of patients had a favorable outcome with a mean mRs of 2.33±1.136. Multivariable logistic binary regression identified hemorrhagic recurrence (P=0.040), lower cranial nerve deficit (P=0.019), and BSCMs greater than 15 mm in diameter (P=0.006) as predictive factors for unfavorable surgical outcomes. Conclusion: BSCM size, compromise of lower cranial nerves, and hemorrhagic recurrence before surgery were identified as risk factors associated with unfavorable outcomes of surgically treated BSCMs in this cohort.
Journal of Neurosurgery, Apr 1, 1992
v" The intraoperative anatomical findings of the anterior communicating artery (ACoA) complex in ... more v" The intraoperative anatomical findings of the anterior communicating artery (ACoA) complex in 46 patients with anatomical variations were compared to those in an equal number of patients without variations in order to determine the visualization of the elements of the vascular complex. All patients underwent radical surgery for an ACoA aneurysm by one of three different surgical approaches: transsylvian, anterior interhemispheric, or basal interhemispheric. Visualization of the vascular elements was similar in patients with or without anatomical variations. The differences observed were dependent on the surgical approach selected and on the projection of the aneurysm. It was found that, even when the intraoperative anatomical field and the number of vascular elements visualized are different from those obtained in autopsy studies, the vascular microanatomical characteristics can be confirmed with each surgical approach to the extent necessary to ensure safe clipping ofaneurysms in patients both with and without anatomical variations.
ABSTRACT Effective treatment of cerebral vasospasm is still a matter of concern in clinical neuro... more ABSTRACT Effective treatment of cerebral vasospasm is still a matter of concern in clinical neurosurgery. In refractory cases, the use of intraarterial vasodilators as papaverin or even mechanical angioplasty has been recommended. Experience with intraarterial nimodipine has been seldom reported. From March to November 2004, 23 patients underwent what we define as “chemical angioplasty,” using repeated doses of intraarterial nimodipine for treating refractory vasospasm to other therapeutic modalities. A microcatheter was positioned in the internal carotid artery or the vertebrobasilar system as close as possible to the spastic area. A single 200 mg injection was completed each time until circulation improved or a 1200 mg dose perday was reached. All patients were evaluated using the modified 6-point Rankin scale after the procedure and during neurological follow up. The chemical angioplasty was repeated daily until the vasospasm period was surpassed or there was a failure of the technique and low-density areas (LDA) on the CT scan appeared. The response to this treatment was considered good in seventeen patients (symptomatic vasospasm disappeared with improvement on the Rankin scale), regular in three (symptomatic vasospasm without low-density areas on CT scan), and bad in three (appearance of lowdensity areas on CT scan). It was demonstrated that intraarterial nimodipine decreases the transit time in angiography and improves the cerebral blood volume in the MRI-perfusion sequence without a significant change in the mean transit time. “Chemical” angioplasty with nimodipine can be used repeatedly in some patients with severe vasospasm to prevent the appearance of lowdensity areas on CT scan before mechanical angioplasty is considered.
Neurologia Medico-chirurgica, 1992
A rare case of bilateral abducens nerve paralyses after rupture of an anterior communicating arte... more A rare case of bilateral abducens nerve paralyses after rupture of an anterior communicating artery (AcoA) aneurysm occurred in a 56-year-old female after sudden onset of severe headache. Bilateral ab ducens nerve paralyses were present without additional neuro-ophthalmological signs. Computed tomography revealed subarachnoid hemorrhage (SAH). Angiography showed an AcoA aneurysm (15 mm in diameter, directed anteroinferiorly) that was successfully clipped. Postoperatively, the bilateral abducens nerve paralyses gradually recovered and disappeared 3 months after onset. Bilateral ab ducens nerve paralyses may occur after SAH due to ruptured AcoA aneurysm, and neurosurgeons should be alert to this possibility.
Introduccion. Los aneurismas del tope de la arteria basilar representan cerca del 50% de los aneu... more Introduccion. Los aneurismas del tope de la arteria basilar representan cerca del 50% de los aneurismas de la circulacion posterior. En la actualidad a pesar de los avances en el tratamiento endovascular, los indices de recanalizacion permanecen altos, con mayor riesgo de resangrado a largo plazo. Material y Metodos. Se realizo un estudio retrospectivo de una base de datos llevada de forma prospectiva de todos los aneurismas de la bifurcacion basilar operados en el Instituto Nacional de Neurologia “Manuel Velasco Suarez” de la Ciudad de Mexico en el periodo de 1997-2019. Se analizo la informacion demogra- fica y los resultados quirurgicos. Ademas, se revisaron los aspectos anatomicos basicos y los principales abordajes empleados para tratar estos aneurismas. Resultados. Los aneurismas del tope de la basilar representaron el 1.73% de un total de 1670 aneurismas operados y el 47.5% de los aneurismas de la circulacion posterior (29 casos). Fueron mas frecuentes en el sexo femenino con una relacion 1.2:1. La edad promedio fue de 49.3 anos (rango 22-70 anos). Solo se operaron pacientes con grado neurologico 1-3 de Hunt y Kosnik. La mayor parte fueron aneurismas menores de 10 mm. El 75.8% (n=22) de los casos se originaron en una bifurcacion en posicion normal. Se observo una asociacion con aneurismas multiples en el 37.9% de los casos. La mayor parte (55.1%) presentaron un domo con direccion superior y el 20% fueronaneurismas grandes o gigantes. El abordaje mas utilizado fue el pterional pretemporal. El indice de oclusion total fue del 82.7%. En el seguimiento a 6 meses, 25 pacientes (86%) tuvieron una puntuacion de 0-2 en la escalamodificada de Rankin. La mortalidad global fue del 6.8%. Los resultados mas pobres se obtuvieron en pacientes con aneurismas gigantes y en aquellos que desarrollaron vasoespasmo sintomatico. Conclusiones. La microcirugia ofrece una opcion viable de tratamiento para aneurismas del tope de la basilar. Cuando se tratan en centros de referencia se obtienen resultados quirurgicos muy aceptables e indices de oclusion mayoral obtenido por terapia endovascular.
Stroke, Feb 1, 2016
Brainstem cavernous malformation (BCM) account for 8-22% of all intracranial cavernomas. Currentl... more Brainstem cavernous malformation (BCM) account for 8-22% of all intracranial cavernomas. Currently, they can be treated microsurgically or conservative but it is still difficult to choose the best treatment for each patient. The main objective of our series was to evaluate the long-term functional outcome and recurrence in patients with BCM treated with conservative or surgical treatments. Hypothesis: We assessed the hypothesis that surgical and conservative treatments are associated with different functional outcome and re-hemorrhage rate in long-term follow-up. Methods: In this non-randomized, clinical series, we compared the clinical and radiological findings of patients with their first hemorrhage secondary to confirmed BCM, treated in a tertiary neurological center, during a twenty five- year period. Treatment of each patient was selected by the attending physician and consisted of either conservative or surgical evacuation of BCM. The primary end-points were recurrent hemorrhage and functional outcome. Favorable prognosis was defined as modified Rankin scale (mRs) of 0 to 2. Results: From January of 1990 to July of 2015; 99 patients with BCM hemorrhage were treated (59 [59,6%] female; mean age 37± 13 years). 37 patients (37,4%) were surgically treated and 62 (62,6%) received conservative treatment. During the follow-up; 20 patients in the medical group (median time of recurrence: 34,5 months; IQR: 13,75-93) and 4 patients in the surgical group (median time of recurrence: 22 months; IQR: 9-46,5) had a recurrence (OR: 0,255; 95% IC: 0,079-0,817), with a cumulative incidence of 5,1 per 100 years-person and 3,96 per 100 years-person respectively. Because of rebleeding, 11 patients of the conservative group were taken to surgery and 3 of the surgical group were to required re-intervention. At the end of follow-up (median: 51 months; IQR: 19-104) 51 patients remained in the conservative group and 28 (54,9%) had a favorable mRs. 48 patients remained in the surgical group and 27 (56,2%) had a favorable mRs (OR:0,94 95% IC: 0,42-2,09). Conclusion: Despite a significant high recurrent hemorrhage rate was observed in conservative treated patients, we did not found difference in clinical outcome between both groups of patients with BCM.
PubMed, Mar 1, 1993
Ischemic cerebrovascular disease is an important cause of morbidity and mortality. One common fin... more Ischemic cerebrovascular disease is an important cause of morbidity and mortality. One common final pathway in neuronal ischemic damage is the uncontrolled influx of calcium into the cell, mediated by voltage dependent channels or activation of the NMDA (N-methyl D-aspartate) receptor. The therapeutic utility of a non-competitive NMDA blocker (MK-801, 2 mg/kg i.p.), to prevent the neuronal ischemic damage in an experimental middle cerebral artery occlusion model has been tested. The drug was administered 10 minutes before (group 3) and one hour after the arterial occlusion (group 4), and the results were compared with a group in which no medicament was utilized (group 2) and a control group (sham operation, group 1). MK-801 reduced significantly the area of infarction in relation to the control group (p < 0.05), mainly if the MK-801 was administered before the occlusion (group 3). These results suggest that MK-801 may be useful for the prevention of the neuronal ischemic damage caused by focal ischemia. However, before recommending its use in humans, all the possible collateral effects must be defined.
Archivos de neurociencias (México, D.F.), Mar 1, 2005
In this paper, is presented the case of a 32-year-old, righ-handed male patient, with a clinical ... more In this paper, is presented the case of a 32-year-old, righ-handed male patient, with a clinical picture characterized by facial pain and diplopia 12 months before admission. The patient was then a worker in the United States of America and received medical attention there. After performing a CT sean, no definite diagnosis could be established. The patient returned to Mexico
Archivos de neurociencias, 2006
Archivos de neurociencias (México, D.F.), Jan 4, 2005
In this paper, is presented the case of a 32-year-old, righ-handed male patient, with a clinical ... more In this paper, is presented the case of a 32-year-old, righ-handed male patient, with a clinical picture characterized by facial pain and diplopia 12 months before admission. The patient was then a worker in the United States of America and received medical attention there. After performing a CT sean, no definite diagnosis could be established. The patient returned to Mexico
Acta neurochirurgica, 2008
Background Even when there is a CT scan classification for the evaluation of subarachnoid haemorr... more Background Even when there is a CT scan classification for the evaluation of subarachnoid haemorrhage (SAH) and clinical outcome (Fisher’s scale), until now, there is not an angiographic scale currently in use that correlates the vasospasm extent with the clinical outcome.
Cureus, Jan 25, 2022
Association between cerebral aneurysms and sellar tumors has been previously reported. Rupture of... more Association between cerebral aneurysms and sellar tumors has been previously reported. Rupture of anterior circulation aneurysms during a transsphenoidal surgery causing massive subarachnoid hemorrhage (SAH) is uncommon, but rupture of a posterior circulation aneurysm is an infrequent event. We present three cases of SAH secondary to rupture of an undetected posterior circulation aneurysm during transsphenoidal surgery to treat a sellar tumor. The common factor in these cases was the adverse outcome despite treatment. The fatal outcome seen in all these cases questions whether to include a (magnetic resonance) MR angiography or (computed tomography) CT angiography during preoperative evaluation for sellar tumors in order to identify inadvertently associated aneurysms.
High Performance Computer Applications, 2016
The results described in this chapter are part of a larger project. The long term goal of this pr... more The results described in this chapter are part of a larger project. The long term goal of this project is to help physicians predict the hemodynamic changes, and associated risks, caused by different treatment options for brain arteriovenous malformations. First, we need to build a model of the vascular architecture of each specific patient, our approach to build these models is described in this chapter. Later we will use the model of the vascular architecture to simulate the velocity and pressure gradients of the blood flowing within the vessels, and the stresses on the blood vessel walls, before and after treatment. We are developing a program to describe each blood vessel as a parametric curve, where each point within this curve includes a normal vector that points in the opposite direction of the pressure gradient. The shape of the cross section of the vessel in each point is described as an ellipse. Our program is able to describe the geometry of a blood vessel using as an input a cloud of dots. The program allows us to model any blood vessel, and other tubular structures.