Ruptured Middle Cerebral Artery Aneurysms Research Articles

Surgical management of middle cerebral artery aneurysms

Background. The middle cerebral artery (MCA) harbors approximately 14% to 30% of all ruptured cerebral aneurysms. They can occur at multiple sites throughout the course of the middle cerebral artery, but most often are found at the bifurcation of the first segment (M1).
 Methods. A retrospective review of 116 consecutive patients with an MCA aneurysm treated by surgical clipping, by two senior neurosurgeons, was performed. The data of all our consecutive patients were searched to obtain patient characteristics, details of the aneurysm size and orientation, treatment details, complications and follow up. At admission, the clinical condition of all patients was classified according to the Hunt and Hess scale. Clinical outcome was graded according to the modified Rankin scale. The follow-up period varied widely from 2 to 72 months (mean 30 months).
 Results. Surgical clipping was performed for 113 ruptured MCA aneurysms; only in 3 cases the aneurysm was unruptured. Fourteen patients presented with significant hematoma which required the evacuation of the clot. Post-operative control angiography was performed in 32 patients (27.5%), from which we reported a full occlusion of the aneurysm in 32 patients (93.75%). Perioperative mortality was 5.2% (6 patients), due to neurological (4 patients) or systemic causes (2 patients). The outcome was graded mRankin 0–2 in 72.5% of the cases (84 patients) at the end of the first postoperative months, and 78.5% (91 patients) at six months follow-up. The most important improvement was recorded for patients graded mRankin 1-2 at the first month follow-up. All 3 patients with a surgically treated asymptomatic MCA aneurysm had an excellent outcome (mRS 0) at both follow-up, 1 months and respectively 6 months.
 Conclusions. For the experienced neurovascular team, MCA aneurysms currently make microsurgical treatment the preferred treatment modality for most MCA aneurysms.

Decreased wall shear stress at high-pressure areas predicts the rupture point in ruptured intracranial aneurysms.

Degenerative cerebral aneurysm walls are associated with aneurysm rupture and subarachnoid hemorrhage. Thin-walled regions (TWRs) represent fragile areas that may eventually lead to aneurysm rupture. Previous computational fluid dynamics (CFD) studies reported the correlation of maximum pressure (Pmax) areas and TWRs; however, the correlation with aneurysm rupture has not been established. This study aims to investigate this hemodynamic correlation. The aneurysmal wall surface at the Pmax areas was intraoperatively evaluated using a fluid flow formula under pulsatile blood flow conditions in 23 patients with 23 saccular middle cerebral artery (MCA) bifurcation aneurysms (16 unruptured and 7 ruptured). The pressure difference (Pd) at the Pmax areas was calculated by subtracting the average pressure (Pave) from the Pmax and normalized by dividing this by the dynamic pressure at the aneurysm inlet side. The wall shear stress (WSS) was also calculated at the Pmax areas, aneurysm dome, and parent artery. These hemodynamic parameters were used to validate the correlation with TWRs in unruptured MCA aneurysms. The characteristic hemodynamic parameters at the rupture points in ruptured MCA aneurysms were then determined. In 13 of 16 unruptured aneurysms (81.2%), Pmax areas were identified that corresponded to TWRs. In 5 of the 7 ruptured cerebral aneurysms, the Pmax areas coincided with the rupture point. At these areas, the Pd values were not higher than those of the TWRs in unruptured cerebral aneurysms; however, minimum WSS, time-averaged WSS, and normalized WSS at the rupture point were significantly lower than those of the TWRs in unruptured aneurysms (p < 0.01). At the Pmax area of TWRs, decreased WSS appears to be the crucial hemodynamic parameter that indicates the risk of aneurysm rupture.

Long-term results of middle cerebral artery aneurysm clipping in the Barrow Ruptured Aneurysm Trial.

A direct comparison of endovascular versus microsurgical treatment of ruptured middle cerebral artery (MCA) aneurysms in randomized trials is lacking. As endovascular treatment strategies continue to evolve, the number of reports of endovascular treatment of these lesions is increasing. Herein, the authors report a detailed post hoc analysis of ruptured MCA aneurysms treated by microsurgical clipping from the Barrow Ruptured Aneurysm Trial (BRAT). The cases of patients enrolled in the BRAT who underwent microsurgical clipping for a ruptured MCA aneurysm were reviewed. Characteristics of patients and their clinical outcomes and long-term angiographic results were analyzed. Fifty patients underwent microsurgical clipping of a ruptured MCA aneurysm in the BRAT, including 21 who crossed over from the endovascular treatment arm. Four patients with nonsaccular (e.g., dissecting, fusiform, or blister) aneurysms were excluded, leaving 46 patients for analysis. Most (n = 32; 70%) patients presented with a Hunt and Hess grade II or III subarachnoid hemorrhage, with a high prevalence of intraparenchymal blood (n = 23; 50%), intraventricular blood (n = 21; 46%), or both. At the last follow-up (up to 6 years after treatment), clinical outcomes were good (modified Rankin Scale score 0–2) in 70% (n = 19) of 27 Hunt and Hess grades I–III patients and in 36% (n = 4) of 11 Hunt and Hess grade IV or V patients. There were no instances of rebleeding after the surgical clipping of aneurysms in this series at the time of last clinical follow-up. Microsurgical clipping of ruptured MCA aneurysms has several advantages over endovascular treatment, including durability over time. The authors report detailed outcome data of patients with ruptured MCA aneurysms who underwent microsurgical clipping as part of a prospective, randomized trial. These results should be used for comparison with future endovascular and surgical series to ensure that the best results are being achieved for patients with ruptured MCA aneurysms.

Ruptured Middle Cerebral Artery Aneurysms: A Single-Center Series Evaluating Microsurgical and Endovascular Treatment

AbstractBackground: Middle cerebral artery (MCA) represents 20% and is the 3rd most common location of intracranial aneurysms (IAs). MCA aneurysms are close to brain surface; this made surgical clipping the standard treatment for them. New advances in endovascular techniques and devices in-creased feasibility and safety of coiling of MCA aneurysms.Aim of the Study: The aim of this study is to evaluate and compare feasibility, safety and outcome of surgical versus endovascular treatment of ruptured MCA aneurysms.Patients and Methods: A retrospective study was done on 38 patients with ruptured MCA aneurysms who were treated between October 2013 and May 2017 at the Neurosurgery Department of Tanta University hospitals. They were divided into 2 groups: Surgical clipping (20 patients) and endovascular coiling (18 patients). Feasibility, complications and outcome were recorded and analyzed.Results: The study included 38 patients with MCA aneu-rysms, 23 females and 15 males. The mean age was 53.5 years (20-67 years). Our microsurgical cases included 20 patients presenting with SAH and good clinical condition, Hunt & Hess score 1 and 2 in 60%. At discharge, 16 (80%) had good GOS and 4 (20%) patients had poor GOS. After endovascular management of MCA aneurysms, all the 18 cases had favorable outcome (GOS grade 5&4) which remained the same at the last follow-up. The rate of total MCA aneurysm occlusion in control angiogram performed after microvascular management was 100 % and at the last follow-up was the same. The rate of total MCA aneurysm occlusion in control angiogram at the end of the endovascular procedure was 72%, subtotal occlusion was achieved in 3 patients (17%) and incomplete occlusion in another 2 patients (11%).Conclusion: Clipping and coiling for ruptured MCA aneurysms have comparable outcome. Microsurgery has less cost, good feasibility and more stability. Coiling has higher cost, better feasibility and less stability. However, patient selection is extremely important to optimize the outcomes.

Selection Strategy for Optimal Keyhole Approaches for Middle Cerebral Artery Aneurysms: Lateral Supraorbital Versus Minipterional Craniotomy

The lateral supraorbital (LS) and minipterional (MP) approaches have been reported for treating intracranial aneurysms as alternative to the pterional approach. We describe our decision making for selecting the minicraniotomy, LS versus MP, for managing noncomplex aneurysms of the middle cerebral artery (MCA), based on the depth of the aneurysm within the Sylvian fissure. We report on a consecutive case series of 50 patients who underwent clipping of 54 ruptured/unruptured MCA aneurysms by means of LS or MP craniotomies. The distance between the MCA (M1) origin and the aneurysmal neck is key to selection of the approach: LS was used for MCA aneurysms <15 mm from the M1 origin and MP for MCA aneurysms ≥15 mm from the M1 origin. 11 of 50 patients presented with subarachnoid hemorrhage (10 ruptured MCA aneurysms). Overall, 59 aneurysms were successfully clipped (54 of the MCA). The mean distance between the M1 origin and the aneurysmal neck was 10.1 mm (range, 4-17 mm) for patients treated by LS and 20 mm (range, 15-30 mm) for those treated by MP. All but 1 MCA aneurysms were successfully treated. At last follow-up (mean, 14 months), no reperfusion of the clipped aneurysms was observed. Our strategy for selecting the keyhole approach based on the depth of the aneurysm within the Sylvian fissure is efficient and safe. We suggest the use of the LS approach when the aneurysm is <15 mm from the M1 origin and the MP approach when the aneurysm is ≥15 mm from the M1 origin.

Remote Primary Intraventricular Haemorrhage in Case of a Ruptur ed MCA Aneurysm

This is the first documented case report of a simultaneous middle cerebral artery (MCA) aneurysmal subarachnoid hemorrhage (aSAH) and remote third ventricular clot. The occurrence of simultaneous subarachnoid hemorrhage and remote hypertensive intracerebral hemorrhage (ICH) is a rare occurrence and has only been reported three previous times in the literature. Intraventricular hemorrhage (IVH) post aneurysmal subarachnoid hemorrhage is common, where peri-ventricular intracerebral clot has ruptured the ependymal lining. However primary intraventricular hemorrhage (PIVH) without associated parenchymal clot is rare. Migration of blood via outlet foramina of the fourth ventricle through CSF pulsation and flow is thought to be the mechanism for this occurrence and would account for small volumes in the subacute setting. Here, we present a case of a 52-year-old woman with a CT demonstrated spontaneous middle cerebral artery (MCA) bifurcation aneurysmal subarachnoid hemorrhage and a large acute third ventricular clot spanning the foramen Monroe.

Importance of Hematoma Removal Ratio in Ruptured Middle Cerebral Artery Aneurysm Surgery with Intrasylvian Hematoma.

ObjectiveRuptured middle cerebral artery (MCA) aneurysm with intrasylvian hematoma usually accompanied by progressive cerebral swelling with poorer outcomes. The authors present characteristics and importance of intrasylvian hematoma removal in the aneurysm surgery.Materials and MethodsFrom 2012 February to 2014 March, 24 aneurysm surgeries for ruptured MCA aneurysms with intrasylvian hematoma were performed in the authors' clinic. The patients were classified according to three groups. Group A included patients who underwent decompressive craniectomy within a few days after aneurysm surgery due to progressive cerebral swelling, group B included patients for whom decompression was not necessary, and group C included patients who showed severe cerebral swelling on admission and decompressive craniectomy and aneurysm surgery in one stage.ResultsThe mean hematoma volume on admission was 28.56 mL, 24.96 mL, and 66.78 mL for groups A, B and C, respectively. Removal of a larger amount of hematoma was observed on postoperative computerized tomography scan in groups B and C (63.2% and 59.0%) compared with group A (33.4%). Although no statistical difference was found between group A and group B (p = 0.115), it tends to show the lesser amount of hematoma removed, the more likely cerebral swelling will progress.ConclusionThe lesser amount of hematoma in ruptured MCA aneurysm with intrasylvian hematoma tends to show benign clinical course than larger amounts. But, even if the hematoma is not easily removed in the operation, we suggest the other procedures such as continuous external catheter drainage of hematoma to avoid unnecessary coagulation or brain retraction.

Emergency microsurgery for ruptured middle cerebral artery aneurysms with intracerebral hematoma

Objective To investigate the experience and prognosis of emergency microsurgery for the treatment of ruptured middle cerebral artery(MCA)aneurysms with intracerebral hematoma. Methods The case data and follow-up results of 23 patients with ruptured MCA aneurysms with intracerebral hematoma treated with emergency operation at the Department of Neurosurgery, Henan Provincial People's Hospital from January 2009 to May 2014 were analyzed retrospectively. Results All 23 patients underwent emergency microsurgery for hematoma evacuation and aneurysm clipping within 24 hours after symptom onset, and 16 were treated with decompressive craniectomy. One patient had serious cerebral edema at day 3 after procedure, and he was treated with decompressive craniectomy once more. CTA revealed that 1 week after procedure, no residual aneurysm was observed. Five patients complicated with cerebral infarction. Two patients were treated with ventriculoperitoneal shunt after procedure because of having communicating hydrocephalus. The patients were followed up for 2-25 months after procedure. The Glasgow outcome scale(GOS)showed that 6 patients had good recovery, 9 could take care of themselves, 4 had severe disability, 2 were in a persistent vegetative state, and 2 died. The good prognosis rate was 65.2%(15/23)and the mortality rate was 8.7%(2/23). Conclusion Emergency microsurgery for the treatment of ruptured MCA aneurysms with intracerebral hematoma can achieve satisfactory prognosis. Key words: Intracranial aneurysm; Middle cerebral artery; Microsurgery; Intracerebral hematoma

Intraoperative premature rupture of middle cerebral artery aneurysms: risk factors and sphenoid ridge proximation sign

OBJECTIVE This study was an investigation of surgical cases of a ruptured middle cerebral artery (MCA) aneurysm that was conducted to identify the risk factors of an intraoperative premature rupture. METHODS Among 927 patients with a ruptured intracranial aneurysm who were treated over an 8-year period, the medical records of 182 consecutive patients with a ruptured MCA aneurysm were examined for cases of a premature rupture, and the risk factors were then investigated. The risk factors considered for an intraoperative premature rupture of an MCA aneurysm included the following: patient age; sex; World Federation of Neurosurgical Societies clinical grade; modified Fisher grade; presence of an intracerebral hemorrhage (ICH); location of the ICH (frontal or temporal); volume of the ICH; maximum diameter of the ruptured MCA aneurysm; length of the preaneurysmal M1 segment between the carotid bifurcation and the MCA aneurysm; and a sign of sphenoid ridge proximation. The sphenoid ridge proximation sign was defined as a spatial proximation < 4 mm between the sphenoid ridge and the rupture point of the MCA aneurysm, such as a daughter sac, irregularity, or dome of the aneurysm, based on the axial source images of the brain CT angiography sequences. RESULTS A total of 11 patients (6.0%) suffered a premature rupture of the MCA aneurysm during surgery. The premature rupture occurrences were classified according to the stage of the surgery, as follows: 1) craniotomy and dural opening (n = 1); 2) aspiration or removal of the ICH (n = 1); 3) retraction of the frontal lobe (n = 1); 4) dissection of the sphenoid segment of the sylvian fissure to access the proximal vessel (n = 4); and 5) perianeurysmal dissection (n = 4). The multivariate analysis with a binary logistic regression revealed that presence of a sphenoid ridge proximation sign (p < 0.001), presence of a frontal ICH associated with the ruptured MCA aneurysm (p = 0.019), and a short preaneurysmal M1 segment (p = 0.043) were all statistically significant risk factors for a premature rupture. Plus, a receiver operating characteristic curve analysis revealed that a preaneurysmal M1 segment length ≤ 13.3 mm was the best cutoff value for predicting the occurrence of a premature rupture (area under curve 0.747; sensitivity 63.64%; specificity 81.66%). CONCLUSIONS Patients exhibiting a sphenoid ridge proximation sign, the presence of a frontal ICH, and/or a short preaneurysmal M1 segment are at high risk for an intraoperative premature rupture of a MCA aneurysm. Such high-risk MCA aneurysms have a superficial location close to the arachnoid in the sphenoidal compartment of the sylvian fissure and have a rupture point directed anteriorly.

Abstract WP90: Intraoperative Premature Rupture of Middle Cerebral Artery Aneurysms: Risk Factors and Sphenoid Ridge Proximation Sign

Object: The investigation of surgical cases of a ruptured middle cerebral artery (MCA) aneurysm to identify the risk factors of an intraoperative premature rupture. Methods: Based on an 8-year period and among 927 patients with a ruptured intracranial aneurysm, the medical records of 182 consecutive patients with a ruptured MCA aneurysm were examined for cases of a premature rupture, and the risk factors were then investigated. The considered risk factors included: the patient age, gender, WFNS clinical grade, modified Fisher grade, presence of an ICH, frontal ICH, temporal ICH, volume of the ICH, maximum diameter of the ruptured MCA aneurysm, length of the pre-aneurysmal M1 segment between the carotid bifurcation and the MCA aneurysm, and the presence of a sphenoid ridge proximation sign. The use of axial source images and a three-dimensional reconstruction of the brain CTA revealed a sphenoid ridge proximation sign based on the spatial proximation between a potential rupture point of the MCA aneurysm and the cortical arachnoid of the sphenoidal sylvian fissure, adjacent superficial sylvian veins, and the sphenoid ridge. Results: A total of 11 patients (6.0%) suffered a premature rupture of the MCA aneurysm during surgery. The premature rupture occurrences were classified according to the stage of the surgery as follows: 1) craniotomy and dural opening (n = 1), 2) aspiration or removal of the ICH (n = 1), 3) retraction of the frontal lobe (n = 1), 4) dissection of the sphenoid segment of the sylvian fissure to access the proximal vessel (n = 4), and 5) peri-aneurysmal dissection (n = 4). Univariate and multivariate analyses revealed that the presence of a sphenoid ridge proximation sign, a frontal ICH associated with the ruptured MCA aneurysm, and the length of the pre-aneurysmal M1 segment were all statistically significant risk factors for a premature rupture of a MCA aneurysm. Conclusions: Patients exhibiting a sphenoid ridge proximation sign, the presence of a frontal ICH, and/or a short pre-aneurysmal M1 segment are high-risk patients for an intraoperative premature rupture of a MCA aneurysm. Such high-risk MCA aneurysms have a superficial location close to the arachnoid in the sphenoidal compartment of the sylvian fissure and have a rupture point directing anteriorly.

Evaluation of surgical technique on outcomes from ruptured aneurysms of the middle cerebral artery

Objective: To determine the effect of surgical technique on outcomes from ruptured middle cerebral artery aneurysms (RMCAA).Methods: A retrospective review was performed of patients with RMCAA, who were treated at the authors’ institutions. The study compares the clipping efficacy, the postoperative CT findings as well as the clinical outcome in 87 acute operated patients. Forty patients who underwent a surgical adapted technique to the preoperative radiological findings in the last 2 ½ years were included in Group 1, and 47 previously operated cases who underwent a standardized pterional approach with aneurysm preparation from proximal to distal were included in Group 2.Results: Angiographically assessed clip efficacy confirmed aneurysm occlusion in 87.5% of the patients in Group 1 and in 70.2% for Group 2 (p < 0.05). In 13 cases (32.2%) of Group 1 versus 27 cases (57.4%) of Group 2, postoperative CT scan showed hypodense brain areas (p < 0.05). In 2 cases of Group 1 versus 8 cases of Group 2, a residual haematoma was found. Three months after bleeding, 25 cases in Group 1 showed a good recovery, 10 a moderate disability, and 5 severe disability or death. In Group 2, 26 patients showed a good recovery, 9 a moderate disability, and 12 severe disability or death. There was a difference for patients with severe disability/death between both groups (p < 0.001).Conclusion: Individually adapted surgical technique in patients with RMCAA improves the efficacy of aneurysm clipping and clot removal, reduces postoperative hypodense brain areas and improves the patients’ outcome.

Surgical management of ruptured middle cerebral artery aneurysms with large intraparenchymal or sylvian fissure hematomas.

Craniotomy for hematoma evacuation and aneurysm clipping is the treatment modality of choice for ruptured middle cerebral artery (MCA) aneurysms with intracranial hematomas. Recent literature suggests that endovascular coil embolization followed by hematoma evacuation can be an acceptable alternative. To determine neurological outcomes in patients with ruptured MCA aneurysms and intraparenchymal or sylvian fissure hematomas. The records of 49 patients with ruptured MCA aneurysms with large intracranial hematomas treated with hematoma evacuation and aneurysm clipping between January 2000 and December 2013 were retrospectively reviewed. Within this cohort, 35 patients (71.4%) were Hunt and Hess grade IV or V on presentation. The mean hematoma volume was 100.4 ± 77.2 mL. Craniectomy was performed in 40 patients (81.6%). Angiographic vasospasm developed in 15 patients (30.6%). The in-hospital mortality rate was 28.6% (14 patients). At a mean of 25.3 ± 34.0 months follow-up, a good outcome (modified Rankin Scale [mRS] score 0-3) was observed in 18 patients (36.7%). Significant factors associated with poor outcome or death (mRS scores of 4-6) included increasing age (P < .01), increasing Hunt and Hess grade (P = .03), increasing modified Fisher grade (P = .01), presence of intraventricular hemorrhage (P < .01), decreasing percentage of hematoma evacuation (P < .05), need for craniectomy (P <. 01), need for external ventricular drainage (P = .04), and angiographic vasospasm (P = .02). MCA aneurysm rupture with concomitant large intraparenchymal or sylvian fissure hematoma formation carries a grave prognosis. Simultaneous hematoma evacuation and aneurysm clipping with or without craniectomy can be an effective treatment modality.

Stent Placement for Complex Middle Cerebral Artery Aneurysms

To evaluate the safety and effectiveness of stent placement for ruptured or unruptured middle cerebral artery (MCA) aneurysms in a larger number. Between October 2003 and December 2012, data for 70 patients with 72 complex MCA aneurysms treated with stents at our institution were retrospectively collected and analyzed. Eighty-five stents were successfully deployed in this series. However, failure of followed coiling was encountered in 2 (2.8%) tiny aneurysms of them. Of the 63 aneurysms treated with stent-assisted coiling, complete occlusion was achieved in 22 (34.9%), neck remnant in 15 (23.8%), and residual sac in 26 (36.5%). Of the 9 aneurysms treated with stent alone, the results were contrast stasis in 3 aneurysms and no change in 6. Procedure-related complications occurred in 9 (12.5%) procedures, including 7 of 27 (25.9%) with ruptured aneurysms and 2 of 45 (4.4%) with unruptured aneurysms, which resulted in 1 death and 5 disabilities. Univariate and multivariate analyses show that ruptured aneurysm is an independent factor for the outcome of these patients (odds ratio, 7.35; 95% confidence interval, 1.35-40.0). Angiographic follow-up results (mean, 10.5±8.8 months) showed that 72.1% (44 of 61) were completely occluded, 4.9% (3 of 61) recurred, and others were stable or had improved. Intrastent stenosis was observed in 1 (1.6%) patient, which was managed conservatively. During a clinical follow-up period ranging from 7 to 113 months (mean, 33.0±22.4 months), 1 disabled patient died from severe pneumonia, whereas the clinical status of the others had improved or was stable. Procedure-related morbidity/mortality during the follow-up for the ruptured and unruptured groups were 3.7%/3.7% and 0/0, respectively. Our study shows that stent placement for the treatment of certain wide-neck MCA aneurysms is feasible, safe, and effective. However, stent placement for acutely ruptured MCA aneurysms harbors a much higher complication rate.

Effect of Insular Injury on Autonomic Functions in Patients With Ruptured Middle Cerebral Artery Aneurysms

Insular injuries are known to cause autonomic derangements. Patients with ruptured middle cerebral artery aneurysms frequently develop temporal hematomas (THs) in addition to subarachnoid hemorrhages, and those with TH may sustain autonomic derangements more frequently than those without TH. Hemispheric lateralization in autonomic derangements has been reported in patients with insular ischemic stroke, and this study was conducted to clarify whether such lateralization was also observed in patients with TH resulting from middle cerebral artery aneurysm rupture. A retrospective analysis on the medical records of 79 patients with ruptured middle cerebral artery aneurysms was performed on the basis of lateralization and presence of TH. They were quadrichotomized as left TH+ (LTH+; n=17), right TH+ (n=25), left TH- (n=15), and right TH- (n=22). Comparisons, mainly between LTH+ and right TH+, were made on demographic variables, autonomic/cardiac parameters, plasma catecholamine and glucose levels, and outcomes. There were no significant differences in demographic or cardiac parameters between the 2 groups. Systolic blood pressures were lower in LTH+ (139±34 versus 174±47 mm Hg; P=0.05). The LTH+ group also tended to be more bradycardiac (80±19 versus 101±22 bpm; P=0.13). The LTH+ group exhibited significantly lower plasma norepinephrine (1008±975 versus 2549±2133 pg/mL; P=0.03) and glucose levels (9.3±1.8 versus 12.2±4.5 mmol/L; P=0.04). However, in-hospital mortality did not differ significantly (41% versus 44%; P=1.00). Lateralization of autonomic derangements observed might not have had a significant effect on the outcomes. Nevertheless, autonomic derangements associated with insular injury should be considered in the management of subarachnoid hemorrhage patients with TH.

A Novel Craniotomy Simulator Provides a Validated Method to Enhance Education in the Management of Traumatic Brain Injury

Abstract BACKGROUND: The middle cerebral artery (MCA) is the most frequent location for unruptured intracranial aneurysms. Controversy remains as to which unruptured MCA aneurysms should be treated prophylactically. OBJECTIVE: To identify independent topographical and morphological variables that could predict increased rupture risk of MCA aneurysms. METHODS: A retrospective analysis of computed tomography angiography data of 1009 consecutive patients with 1309 MCA aneurysms, referred between 2000 and 2009 to Helsinki University Hospital, was carried out. Morphological and topographical parameters examined for MCA aneurysms comprised aneurysm wall regularity, size, neck width, aspect ratio, bottleneck factor, height-width ratio, location along the MCA, side, distance from the internal carotid artery bifurcation, and dome projection in axial and coronal computed tomography angiography views. Univariate and multivariate logistic regression analyses were performed to determine independent risk factors for rupture. RESULTS: Of the 1309 MCA aneurysms, 69% were unruptured and 31% were ruptured. Most unruptured MCA aneurysms were smaller than 7 mm (78%), with a smooth wall (80%) and a height-width ratio of 1 (47%) and were located at the main bifurcation (57%). Ruptured MCA aneurysms, mostly 7 to 14 mm in size (55%), had an irregular wall (78%) and a height-width ratio greater than 1 (72%) and were located at the main bifurcation (77%). Thirty-eight percent of MCA bifurcation aneurysms, 74% of large aneurysms, 64% of aneurysms with an irregular wall, and 49% of aneurysms with a height-width ratio greater than 1 were ruptured. CONCLUSION: Location at the main MCA bifurcation, wall irregularity, and less spherical geometry were independently associated with rupture of MCA aneurysms with a correlation with aneurysm size.

A New, More Accurate Classification of Middle Cerebral Artery Aneurysms

Classification of middle cerebral artery (MCA) aneurysms is sometimes difficult because the identification of the main MCA bifurcation, the key for accurate classification of MCA aneurysms, is inconsistent and somewhat subjective. To use the meeting point of the M1 and M2 trunks as an objective, generally accepted, and angiographically evident hallmark for identification of MCA bifurcation and more accurate classification of MCA aneurysms. We reviewed the computed tomographic angiography data of 1009 consecutive patients with 1309 MCA aneurysms. The M2 trunks were followed proximally until their meeting with the M1 trunk at the main MCA bifurcation. The aneurysms were classified according to their relative location: proximal, at, or distal to the MCA bifurcation. The M1 aneurysms were further subgrouped into M1 early cortical branch aneurysms and M1 lenticulostriate artery aneurysms, extending the classic 3-group classification of MCA aneurysms into a 4-group classification. The main MCA bifurcation was the most common location for MCA aneurysms, harboring 829 aneurysms (63%). The 406 M1 aneurysms comprised 242 M1 early cortical branch aneurysms (60%) and 164 M1 lenticulostriate artery aneurysms (40%). We found 106 MCA aneurysms (8%) at the origin of large early frontal branches simulating M2 trunks liable to be misclassified as MCA bifurcation aneurysms. Even though 51% of the 407 ruptured MCA aneurysms were associated with an intracerebral hematoma, this did not affect the classification. Studying MCA angioarchitecture and applying the 4-group classification of MCA aneurysms is practical and facilitates the accurate classification of MCA aneurysms, helping to improve surgical outcome.

Comparative Results of the Patients with Intracerebral and Intra-sylvian Hematoma in Ruptured Middle Cerebral Artery Aneurysms

ObjectiveTo clarify the prognosis of the patients with intra-sylvian hematoma (ISH) and intracerebral hematoma (ICH) in ruptured middle cerebral artery (MCA) aneurysms.MethodsWe categorized hematoma into ISH and ICH by the presence of intra-hematomal contrast enhancing vessel (IHCEV) on computed tomography angiography (CTA). Forty-four ruptured MCA aneurysm patients with ICH or ISH were grouped by the grading system proposed by the authors in our previous study. We investigated the relevance of the following factors: patient's age, gender, Hunt-Hess grade, Glasgow outcome scale (GOS) and changes in Glasgow coma scale (GCS) between pre-operation and 7 days after operation.ResultsThere were no significant differences statistically in age, gender, Hunt-Hess grade, and GOS between the ISH and ICH groups. In their peri-operative GCS change, the ICH group showed greater improvement compared to the ISH group (p = 0.0391). The hematoma grade had a significant relevance with the patients' GOS.ConclusionAlthough there were no significant statistic differences in the GOS of the 2 hematoma groups, there were prominent improvements of post-operative GCS in the ICH group. Unlike in the ISH group, effective removal of hematoma was possible in most patients of the ICH group. Thus although there is no difference in the prognosis of the 2 groups, early surgical evacuation of hematoma seems to be effective in improving the short-term GCS score in peri-operative period.

Differences in simple morphological variables in ruptured and unruptured middle cerebral artery aneurysms

Management of unruptured intracranial aneurysms remains controversial in neurosurgery. The contribution of morphological parameters has not been included in the treatment paradigm in a systematic manner or for any particular aneurysm location. The authors present a large sample of middle cerebral artery (MCA) aneurysms that were assessed using morphological variables to determine the parameters associated with aneurysm rupture. Preoperative CT angiography (CTA) studies were evaluated using Slicer software to generate 3D models of the aneurysms and their surrounding vascular architecture. Morphological parameters examined in each model included 5 variables already defined in the literature (aneurysm size, aspect ratio, aneurysm angle, vessel angle, and size ratio) and 3 novel variables (flow angle, distance to the genu, and parent-daughter angle). Univariate and multivariate statistical analyses were performed to determine statistical significance. Between 2005 and 2008, 132 MCA aneurysms were treated at a single institution, and CTA studies of 79 aneurysms (40 ruptured and 39 unruptured) were analyzed. Fifty-three aneurysms were excluded because of reoperation (4), associated AVM (2), or lack of preoperative CTA studies (47). Ruptured aneurysms were associated with larger size, greater aspect ratio, larger aneurysm and flow angles, and smaller parent-daughter angle. Multivariate logistic regression revealed that aspect ratio, flow angle, and parent-daughter angle were the strongest factors associated with ruptured aneurysms. Aspect ratio, flow angle, and parent-daughter angle are more strongly associated with ruptured MCA aneurysms than size. The association of parameters independent of aneurysm morphology with ruptured aneurysms suggests that these parameters may be associated with an increased risk of aneurysm rupture. These factors are readily applied in clinical practice and should be considered in addition to aneurysm size when assessing the risk of aneurysm rupture specific to the MCA location.

Iatrogenic dural arteriovenous fistula and aneurysmal subarachnoid hemorrhage

The authors present the case of a patient who presented acutely with aneurysmal subarachnoid hemorrhage (SAH) and a contralateral iatrogenic dural arteriovenous fistula (DAVF). Diagnostic angiography was performed, revealing a right-sided middle cerebral artery (MCA) aneurysm and a left-sided DAVF immediately adjacent to the entry of the ventriculostomy and bur hole site. A craniotomy was performed for clipping of the ruptured MCA aneurysm, and the patient subsequently underwent endovascular obliteration of the DAVF 3 days later. The authors present their treatment of an iatrogenic DAVF in a patient with an aneurysmal SAH, considerations in management options, and a literature review on the development of iatrogenic DAVFs.

The meaning of the prognostic factors in ruptured middle cerebral artery aneurysm with intracerebral hemorrhage.

ObjectiveThis study analyzed the relationship between prognosis and multiple clinical factors of ruptured middle cerebral artery (MCA) aneurysm with intracerebral hemorrhage (ICH), to aid in predicting the results of surgical treatment.MethodsEnrolled subjects were 41 patients with ruptured MCA aneurysm with ICH who were treated with surgical clipping. Clinical factors such as gender, age, and initial Glasgow coma scale were assessed while radiological factors such as the volume and location of hematoma, the degree of a midline shift, and aneurysm size were considered retrospectively. Prognosis was evaluated postoperatively by Glasgow outcome scale.ResultsAge and prognosis were correlated only in the groups with ICH over 31 mL or ICH at the frontal lobe or sylvian fissure. When initial mental status was good, only patients with ICH on the temporal lobe had a better prognosis. If the midline shift was less than 4.5 mm, the probability of better prognosis was 95.5% (21 of 22). If the midline shift was more than 4.5 mm, the probability of poor prognosis was 42.1% (8 of 19). Patients with ICH less than 31 mL had higher survival rates, whereas if the ICH was more than 31 mL, 41.2% (7 of 17) had a poor clinical pathway.ConclusionEven if the initial clinical condition of the patient was not promising, by carefully examining and taking into account all factors, neurosurgeons can confidently recommend surgical treatment for these patients.