Surgical Treatment of Middle Cerebral Artery Aneurysms

Safety and efficacy of the flow diverter device for treating middle cerebral artery aneurysms of the proximal (M1) segment related to the lenticulostriate arteries: A single-center experience

BACKGROUND

Experience using flow diverter devices (FDDs) to treat proximal (M1) middle cerebral artery aneurysms associated with the lenticulostriate artery (M1A-LA) remains limited. This study aimed to examine the efficacy and safety of an FDD to manage M1A-LA.

METHOD

Patients with M1A-LA who received FDD treatment at a single center were included in the analysis. Data on the baseline characteristics, postoperative conditions, and follow-up results of the participants were recorded and analyzed. The aneurysms were categorized into three subtypes based on morphology and location. Aneurysms confined to the M1 segment were categorized as subtype A. Those extending to the M2 segment were classified as subtype B. Aneurysms designated as subtype C were confined to the M1 segment but with another independent aneurysm in the distal artery and the presence of healthy vessels between the two. Subgroup analyses were conducted on these subtypes and aneurysm sizes. To assess the consistency of follow-up results, Cronbach's kappa/alpha was used to calculate inter-rater variability. Somers's D coefficient was used to assess the correlation between each subgroup and the imaging outcomes; Fisher's exact test was used to compare the variability among the subgroups.

RESULT

The cohort comprised 11 patients. Their Modified Rankin Scale scores between the perioperative and follow-up periods did not differ. During the follow-up period, four patients had completely occluded aneurysms, and five patients had partial occlusions. The remaining patients did not present with changes in their aneurysms. The kappa coefficient was 0.864 (p < 0.001). M1A-LA was divided into subtypes A, B, and C. Subtype A (defined as an aneurysm completely located in the M1 segment) had a higher complete occlusion rate than that of subtypes B and C, Somers's D R/C correlation coefficient was 0.553, with a 95% confidence interval of 0.1229-0.9823 (p = 0.009). The radiographic follow-up findings were not significantly correlated with the size of the aneurysm (p = 0.121) or the use of coiling (p = 0.903). No significant differences in subtypes (p = 0.264), aneurysm size (p = 0.657), or coiling use (p > 0.999) were observed.

CONCLUSION

FDDs were safe and possibly effective against M1A-LA. However, they were not as effective as for intracranial aneurysms in other locations. FDDs are a satisfactory treatment option for M1A-LA, particularly for subtype A aneurysms.

Feasibility, Safety, and efficacy of endovascular treatment for M1 hilltop Aneurysms: A retrospective study

OBJECTIVE

This retrospective study aimed to evaluate the feasibility, safety, and efficacy of endovascular treatment (EVT) for M1 hilltop aneurysms, a specific M1 segment subtype located at the highest point of the middle cerebral artery (MCA).

METHODS

The study included 54 patients with M1 hilltop aneurysms who underwent EVT between December 2017 and [end date]. Treatment decisions were based on angiographic findings and patient characteristics. Clinical and radiological data were reviewed, and outcomes were assessed using the Raymond-Roy classification (RRC) and modified Rankin Scale (mRS). Follow-up radiological examinations were conducted at specific intervals.

RESULTS

EVT was successful in all 54 cases. Immediate postprocedural angiograms showed favorable occlusion (RRC I or II) in 59.3% and aneurysm remnants (RRC III) in 40.7%. Procedure-related complications occurred in 7.4% of patients, including thromboembolism and ICA dissection, with no permanent neurological impairment. During a mean 18.2-month follow-up, no neurological deterioration or aneurysmal rupture occurred. Most patients showed stable/improved occlusion on follow-up imaging, with a 14% recurrence rate. Retreatment was required in 2% of cases.

CONCLUSIONS

EVT appears feasible, safe, and effective for treating M1 hilltop aneurysms. It resulted in favorable occlusion and low recurrence/retreatment rates. Neck diameter and stent usage influenced immediate outcomes and recurrence. Larger studies with longer follow-ups are needed to validate these findings further.

Proximal Middle Cerebral Artery Aneurysms: Microsurgical Management and Therapeutic Results

BACKGROUND

Management of proximal (M1) middle cerebral artery (MCA) aneurysms can be challenging. Because of the diversity of aneurysm morphology and location of M1 aneurysms, the surgical strategy should be tailored to each individual case, especially for complex cases. We assessed the safety and efficacy of an algorithmic strategy for the management of M1 aneurysms.

METHODS

A prospective single-center study of M1 aneurysms treated with microsurgery was performed. Our algorithmic strategy was determined by the location and complexity (e.g., size, shape) of the aneurysms. The surgical modalities included neck clipping, aneurysm resection and/or trapping, and proximal occlusion with revascularization. The clinical and radiographic data were analyzed.

RESULTS

From January 2007 to March 2017, 92 proximal MCA aneurysms in 92 patients were treated microsurgically. Aneurysm treatment techniques included clipping in 55, proximal occlusion in 21, aneurysm resection in 11, and trapping in 4. Bypass techniques included 2 anterior temporal artery reconstructions, 5 middle cerebral bifurcation reconstructions, 4 parent artery reanastomoses, 2 interpositional bypasses, 25 high-flow bypasses, and 7 medium-flow bypasses. Overall, good outcomes (modified Rankin scale score, 0-2) were seen in 49 of 92 patients (53.3%) at discharge and in 79 of 91 (86.8%) at the last follow-up visit. On the latest angiogram, 78 of 90 aneurysms (86.7%) had been completely occluded without a remnant. Bypass patency was confirmed in 38 of 43 bypass procedures.

CONCLUSIONS

Our present treating strategy might provide a benefit for patients with proximal MCA aneurysms.

Minimally Invasive Transpalpebral ‘‘Eyelid’’ Approach to Unruptured Middle Cerebral Artery Aneurysms

BACKGROUND: Although recent technological advances have led to successful endovascular treatment, middle cerebral artery (MCA) aneurysms are still prone to surgery. Because minimally invasive options are limited and possess several functional and cosmetic drawbacks, a transpalpebral approach is proposed as a new alternative.

OBJECTIVES: To describe and assess surgical results of the minimally invasive transpalpebral approach in patients with MCA aneurysms.

METHODS: The data of 25 patients with unruptured MCA aneurysms from 2013 to 2016 were included in a cohort prospective database. We describe modifications of the approach and technique for MCA aneurysm clipping, in a step-by-step manner. The outcome was based on complications, procedural morbidity and mortality, and clinical and angiographic outcomes.

RESULTS: All procedures were successfully performed in a standardized way, and no major complications related to the new approach were observed. Twenty-two patients were discharged the day after surgery (88%). The majority of aneurysms were 5 to 6 mm in diameter (mean, 7 mm; range 4-21 mm). All patients underwent postoperative angiographic control, which showed no significant residual neck. A 3-mo follow-up was sufficient to show no visible scars with excellent cosmetic results. The mean duration of follow-up was 16 mo.

CONCLUSION: The transpalpebral approach comes as a minimally invasive, safe, definitive, and cosmetically adequate solution for MCA aneurysms at the present time.

Various techniques of stent-assisted coil embolization of wide-necked or fusiform middle cerebral artery aneurysms : initial and mid-term results

Objective

To evaluate the feasibility and clinical and angiographic outcomes of stent-assisted embolization for complex middle cerebral artery (MCA) aneurysms.

Methods

The records of 23 consecutive patients with 24 MCA aneurysms, who underwent stent-assisted embolization of the aneurysm, were retrospectively evaluated.

Results

Fifteen aneurysms were treated with one stent and 8 were treated using more than two stents (5 a stent-within-a-stent, 1 triple stents, and two Y-stent). Angiographically, complete or near complete occlusion was achieved in 15 aneurysms (65.2%), residual neck in five (21.7%), and residual aneurysm in three (13.1%). Five aneurysms demonstrated thrombosis within the stent during the procedure and hospitalization, and were resolved by intraarterial and intravenous Tirofiban injection. Symptomatic thromboembolic complications were developed in five patients and permanent deficits demonstrated in two patients with modified Rankin Scale 1 and 2, respectively. Treatment-related permanent morbidity and mortality rates were 8.3% and 0% with relatively high complication rate. Angiographic follow-up was available in 17 aneurysms at 6-31 months (mean, 13.2 months) and showed stable or improved in 15 (88.2%) and major and minor recurrence in one, respectively.

Conclusion

Complex MCA aneurysms could be treated by stent-assisted coiling and showed lower recanalization rate during mid-term follow-up by effective flow diversion due to various stent-assisted techniques. Our results warrant further study with a longer follow-up period in a larger sample.

Middle cerebral artery aneurysms: a single-center series comparing endovascular and surgical treatment

OBJECTIVE

The optimal treatment for middle cerebral artery (MCA) aneurysms is controversial. MCA aneurysms have been considered more conducive to surgical treatment. Recent technology has led to successful endovascular treatment of MCA aneurysms. The objective of this study was to analyze the outcomes of endovascular and surgical treatment of MCA aneurysms as experienced by a single tertiary center.

METHODS

We retrospectively reviewed 90 MCA aneurysms in 84 patients treated from 2005 to 2010. They were separated into 2 groups: endovascular coiling, with 50 (59.5%) patients, and surgical clipping, with 34 (40.5%) patients. Outcome was based on complications, procedural morbidity and mortality, clinical and angiographic outcomes, and retreatment rates. Patients were further separated into ruptured and unruptured aneurysm groups.

RESULTS

Ruptured aneurysms were 10 of 50 (20%) and 9 of 34 (26.5%) patients in the endovascular and surgical groups, respectively. Procedure-related complications were 16% and 0% for the endovascular and surgical groups (P = .01), respectively. Overall rate of complete or near-complete occlusion at angiographic follow-up was 86% and 95% for the endovascular and surgical groups (P = .16), respectively. Proportion of patients with modified Rankin scale of 3 to 6 at 6 months follow-up was 10% and 5.9% for the endovascular and surgical groups (P = .5), respectively. The mean angiographic follow-up was 9.02 months (range 0 to 5.2 years). Retreatment rates were 14% and 0% for the endovascular and surgical groups, respectively (P = .01).

CONCLUSIONS

In this nonrandomized sample of 90 MCA aneurysms treated with endovascular coiling or neurosurgical clipping, we observed a similar clinical outcome based on the modified Rankin scale and angiographic occlusion. Complication and retreatment rates were higher but not significant for the endovascular group. Both treatment modalities are good alternatives and should be individualized based on aneurysm angioarchitecture and the patient's general conditions.

Stent-assisted coiling of complex middle cerebral artery aneurysms: initial and midterm results

BACKGROUND AND PURPOSE

Clinical outcome and initial and midterm angiographic results of EVT of complex MCA aneurysms by using the stent-assisted coiling technique were retrospectively evaluated in our center where EVT of intracranial aneurysms is the first treatment option.

MATERIALS AND METHODS

From November 2003 to October 2009, 49 patients (27 men, 22 women; mean age, 52 ± 12 years) harboring 52 complex unruptured MCA aneurysms (11 ruptured previously and coiled but recanalized and 41 unruptured) were treated by EVT by using self-expandable intracranial stents. Procedural complications, clinical outcome, and initial and midterm angiographic results were evaluated. Initial treatment status and aneurysm sac size were tested as potential risk factors for recurrence.

RESULTS

After successful stent deployment, coiling was performed in 50 aneurysms (96.2%) in 47 patients; however, 2 failures (3.8%) occurred in 2 patients. Ten intrastent clot formations (20%) observed on final control angiography induced 2 permanent moderate disabilities (GOS score = 2). Mortality and permanent neurologic morbidity were 0% and 4.3%, respectively. At a mean period of 14 ± 9 months, among 48 aneurysms in 45 patients eligible for follow-up, 34 complete (71%) and 14 partial treatments (29%) were observed, 7 recurrences (14.6%) occurred, and 5 patients (10.4%) needed retreatment. No aneurysm bleeding or symptomatic intrastent stenosis was observed. Aneurysm sac size ≥7 mm and incomplete initial treatment were associated with more recurrences without a statistically significant difference.

CONCLUSIONS

For complex unruptured MCA aneurysms, EVT by using a self-expandable intracranial stent was feasible, safe, and durable and could be considered as the first-option treatment.

Endovascular treatment of 174 middle cerebral artery aneurysms: clinical outcome and radiologic results at long-term follow-up

PURPOSE

To retrospectively evaluate the immediate safety and efficacy as well as the clinical outcome and long-term angiographic results of endovascular treatment (EVT) of middle cerebral artery (MCA) aneurysms.

MATERIALS AND METHODS

This is a retrospective review of patients in whom coiling of MCA aneurysms was attempted over a 7-year period. Institutional review board approval and informed written consent were obtained. This study included 153 patients (90 women, 63 men; mean age, 49.5 years +/- 11.7 [standard deviation]) with 174 MCA aneurysms (71 unruptured, 103 ruptured). Complications of EVT, clinical outcome, and the results of either cerebral digital subtraction angiography (DSA) or magnetic resonance (MR) angiography were analyzed at initial, intermediate (6-18 months), and late (2-7 years) follow-up.

RESULTS

Coiling was performed in 160 (92%) aneurysms in 141 patients. Periprocedural complications were observed in 31 (19.4%) procedures, including aneurysm perforations (n = 7, 4.4%) and thromboembolic events (n = 24, 15.0%). EVT induced permanent morbidity in eight (5.7%) patients, with severe neurologic impairment in three (2.1%) and two deaths (1.4%). Of 114 MCA aneurysms controlled by using DSA (n = 50) or MR angiography (n = 64) at 50 months +/- 14, 73 (64%) remained completely occluded, 31 (27.2%) recurred, and 12 (10.5%) major recurrences were retreated. A balloon remodeling technique allowed treatment of complex aneurysms (n = 63) but was associated with more recurrences in the long term (42.6%) than aneurysms treated without balloon assistance (16.4%; P = .016).

CONCLUSION

EVT of MCA aneurysms was safe and long-term monitoring of patients showed a low rate of recurrence requiring retreatment. However, complex anatomy and long-term recurrences have to be addressed when considering EVT for MCA aneurysms.

Endovascular treatment of middle cerebral artery aneurysms with detachable coils: angiographic and clinical outcomes in 115 consecutive patients

OBJECTIVE

Because of their anatomic configuration, middle cerebral artery (MCA) aneurysms are most often treated with surgical clipping. However, endovascular coil embolization of these aneurysms is an increasingly used alternative. We retrospectively reviewed the anatomic and clinical outcomes of patients with MCA aneurysms who underwent endovascular treatment at our institution.

METHODS

One hundred fifteen MCA aneurysms in 115 patients (mean age, 55.1 years) were treated by an endovascular technique from April 1990 to March 2007. Forty-eight patients (42%) presented with acute subarachnoid hemorrhage, and 67 patients (58%) had unruptured aneurysms. Fifty-three aneurysms (46%) were small with a small neck, 28 (24%) were small with a wide neck, 22 (19%) were large, and 12 (11%) were giant.

RESULTS

Angiographic results immediately after embolization showed complete occlusion in 53 aneurysms (46%), a neck remnant in 51 (44%), and incomplete occlusion in 3 (3%). Because of anatomic difficulties, we could not embolize 8 aneurysms (7%). Thirteen patients underwent combined treatment that included endovascular and extracranial-intracranial bypass surgery. Morbidity and mortality rates were 6.9% (8 patients) and 3% (3 patients), respectively. Procedure-related complications were encountered in 10 patients (9%). Seventy patients had long-term follow- up angiograms. Seven aneurysms (10%) were recanalized; all were large or giant. One partially embolized large aneurysm ruptured 13 months after embolization.

CONCLUSION

In this series, endovascular coil embolization of MCA aneurysms has morbidity and mortality rates comparable to those of conventional surgical clipping. Combined treatment of endovascular and bypass surgery can successfully treat large or giant complex fusiform MCA aneurysms.

Characteristics and management of ruptured distal middle cerebral artery aneurysms

OBJECTIVE

Distal middle cerebral artery (dMCA) aneurysms are very rare with a reported frequency of 2-6%. Typically, patients with ruptured distal MCA aneurysms have poor clinical outcomes because often there is both a subarachnoid haemorrhage (SAH) and an intracerebral haematoma (ICH). The goals of this study were to identify the characteristics of the distal MCA aneurysms and evaluate the optimal treatment for a good outcome.

METHODS

The clinical, neuroradiological and operative records of 8 patients with a ruptured distal MCA aneurysm who underwent surgical management were reviewed retrospectively. The outcomes were presented according to the Glasgow Outcome Scale (GOS).

RESULTS

The clinical characteristics of the patients with ruptured dMCA aneurysms included the following: (1) a fusiform appearance in five out of eight (63%) patients. (2) Mean aneurysm size of 9.4 mm (range 2-35 mm). (3) The location being M2 (insular segment) in three, M2-3 junction in three, and M3 (opercular segment) in two patients. (4) Brain CT images revealed both SAH and an ICH in six of eight (75%) patients with the mean size of the ICH being 10 cc (range 5-25 cc). (5) Re-bleeding occurred in four out of eight (50%) of patients. All patients underwent early surgical treatment and the procedures used for surgical repair were, clipping in five patients, trapping in two, and trapping with end-to-end bypass surgery in one patient. Clinical outcomes were poor in two patients (death) due to severe brain swelling.

CONCLUSIONS

In this study, dMCA aneurysms had a fusiform shape and a high re-bleeding rate; if ruptured, there was generally ICH and SAH. A good clinical outcome was associated with adequate control of brain swelling and early surgery to prevent re-bleeding.

Endovascular treatment with coils of 149 middle cerebral artery berry aneurysms

PURPOSE

To retrospectively evaluate the immediate and long-term clinical results, as well as the angiographic results, of occlusion of middle cerebral artery (MCA) berry aneurysms with coils.

MATERIALS AND METHODS

This retrospective study had institutional review board approval, and informed consent was obtained. One hundred fifty-four MCA aneurysms in 142 patients were intended to be treated. Complications, patient clinical outcomes, and immediate postprocedural and follow-up angiography results were retrospectively evaluated.

RESULTS

One hundred forty-nine (96.8%) of 154 MCA aneurysms (72 ruptured, 77 unruptured) were occluded with coils in 137 patients (99 women and 38 men; age range, 28-76 years; mean, 48 years). Thromboembolic events occurred in 20 (13.4%) and aneurysm perforation occurred in seven (4.7%) of 149 procedures. Endovascular treatment (EVT) was performed without complications for 121 (81.2%) of the treated aneurysms. For ruptured aneurysms, the treatment-related mortality rate was 6% (four of 72 aneurysms) and the treatment-induced permanent morbidity rate was 1% (one aneurysm). For unruptured aneurysms, the treatment-induced mortality rate was 1% (one of 77 aneurysms) and the procedure-related permanent morbidity rate was 3% (two aneurysms). One hundred five (70.5%) of the 149 aneurysms were examined with follow-up angiography at least once. Recurrences were found for 21 (20%) of the 105 aneurysms that were followed up for a cumulative period of 1564 months (mean, 15 months). Of these 21 recurrent aneurysms, 10 increased in size in the interval between follow-up angiography examinations and 11 remained stable. A second treatment was required for 12 aneurysms, and a third treatment was required for one. After repeat EVT, total aneurysm occlusion was attained for nine aneurysms, and a residual neck was seen in two aneurysms. One recurrent aneurysm was surgically clipped. The nine other aneurysms with small recurrences were not candidates for additional treatment.

CONCLUSION

EVT of MCA aneurysms with coils can be successfully performed without inducing neurologic deficits in most patients with ruptured or unruptured aneurysms.

Nuances of middle cerebral artery aneurysm microsurgery

Middle cerebral artery aneurysms, a common source of subarachnoid hemorrhage, occur predominantly at the main bifurcation of the middle cerebral artery. Microsurgical clipping is the most effective treatment of these aneurysms because of their peripheral location, wide necks, and straightforward surgical anatomy. Despite the moderate technical requirements of this type of surgery, patients with ruptured aneurysms often have poor outcomes because of the high incidence of intracerebral hematomas. Although several different surgical approaches can be used, we favor a lateral-to-medial transsylvian approach for most aneurysms. This description of our surgical technique stresses minimizing retraction to avoid injury to the brain and preparing broad-based middle cerebral artery aneurysms for clipping. Management of outcomes when using these techniques also is presented.