Application of magnetic resonance neuronavigation assistance in neurosurgical clipping of pericallosal aneurysms / 中国脑血管病杂志

Objective To investigate the safety and clinical efficacy of magnetic resonance neuronavigation assisted technique in neurosurgical clipping of pericallosal aneurysms. Methods From January 2010 to January 2017,40 consecutive patients with pericallosal aneurysm treated with neurosurgical clipping at the Department of Neurosurgery,the 175th Hospital of PLA were enrolled retrospectively. They were diagnosed by CT angiography (CTA),magnetic resonance angiography (MRA)or digital subtraction angiography (DSA)before operation. According to the different surgical methods,40 patients were divided into either a routine surgical group (n＝18)or a neuronavigation assistance group (n＝22). On the basis of the conventional longitudinal fissure approach,the neuronavigation assistance group was treated with the magnetic resonance neuronavigation technique. The aneurysms and upper drainage vein,design incision and surgical approaches were accurately located. The operation time,surgical complications (edema or infarction after drainage vein injury and secondary bleeding in the operated area)and proportion of good prognosis (the modified Rankin scale [mRS]score ＜3)were compared. Results (1)Under the microscope,40 patients underwent clipping of pericallosal aneurysms via longitudinal fissure approach. Postoperative CTA or DSA confirmed that they were all completed clipped. The operation time of the neuronavigation assistance group were shorter than that of the routine surgical group (2. 5 ± 0. 5 h vs. 3. 5 ± 0. 4 h,t＝1. 254),and the proportion of edema or venous infarction was less than that of the routine surgical group (4. 5%[1／22]vs. 6／18). The difference between the two groups was statistically significant (all P＜0. 05);there were no significant differences in the incidences of accidental rupture and secondary hemorrhage between the two groups (all P＞0. 05). (2)Both groups of patients completed the 6-month follow-up. There were 12 patients (12／18)with good prognosis in the routine surgery group and 20 (90. 9%)with good prognosis in the neuronavigation assistance group. There was no significant difference in the proportion of good prognosis between the two groups (χ2＝3. 545,P＞0. 05). Conclusions The use of magnetic resonance neuronavigation assisted technique helps the precise intraoperative positioning of the lesions and surgical approach optimization,thereby effectively implementing brain protection,reducing the risk of microsurgery, and improving the accuracy and safety of the surgery. It is an effective auxiliary means of neurosurgical clipping of pericallosal aneurysms.

Endovascular Treatment of Aneurysms Arising from the Proximal Segment of the Anterior Cerebral Artery

OBJECTIVE: Aneurysms arising from the proximal segment of the anterior cerebral artery (A1) are rare and challenging to treat. The aim of this study was to report our experience with endovascular treatment of A1 Aneurysms. METHODS: From August 2007 through May 2012, eleven A1 aneurysms in eleven patients were treated endovascularly. Six aneurysms were unruptured and 5 were ruptured. One patient with an unruptured A1 aneurysm presented with subarachnoid hemorrhage due to rupture of an anterior communicating artery aneurysm. Procedural data, clinical and angiographic results were reviewed retrospectively. RESULTS: All of the aneurysms were successfully treated with coil embolization. Six were treated with a simple technique while the remaining 5 required adjunctive technique : double catheters (n=2), balloon-assisted (n=2), and stent-assisted (n=1). The immediate angiographic control showed a complete occlusion in all cases. Procedure-related complication occurred in only one patient : parent artery occlusion, which was not clinically significant. All patients had excellent clinical outcomes but one patient was discharged with a slight disability. No neurologic deterioration or bleeding was seen during the follow-up period in this cohort of patients. Follow-up angiography (mean, 20 months) was available in ten patients and revealed stable occlusion in all cases. CONCLUSION: Endovascular treatment is a feasible and effective therapeutic modality for A1 aneurysms. Tailored microcatheter shaping and/or adjunctive techniques are necessary for successful aneurysm embolization because of the projection and location of A1 aneurysms.

Characteristics and Surgical Outcomes of Distal Anterior Cerebral Artery Aneurysms / 대한뇌혈관외과학회지

OBJECTIVE: Distal anterior cerebral artery (dACA) aneurysms are uncommon, and they require special treatment because of the narrow exposure in the interhemispheric fissures, the dense adhesions between the cingulate gyri and their association with multiple aneurysms or traumatic pseudoaneurysm. The aim of this study was to assess the characteristics and surgical outcomes of dACA aneurysms. METHODS: Among the 520 cases of cerebral aneurysms that were operated on from 1997 to April 2007, we experienced 31 cases of dACA aneurysms that developed in 30 patients. The medical records and radiological findings were retrospectively reviewed. RESULTS: The clinical characteristics of the patients with dACA aneurysms included the following. (1) The incidence of the dACA aneurysm was 5.9% of the total 520 cases, and the dACA aneurysms displayed a female predominance. (2) The most common location of the dACA aneurysms was the junction of the pericallosal and callosomarginal arteries. (3) Multiple aneurysms were found in 12 patients (40%), and the most concomitantly found aneurysm was MCA aneurysm. (4) The larger aneurysms more than 10 mm size all had thrombus in the sac, and their angiographic findings were underestimated compared with their findings on the operative fields. (5) dACA aneurysms shows frequent intracerebral hemorrhage (ICH) and subdural hemorrhage on the initial brain CT scan (28.5%). They also had a higher rate of intraoperative rupture (12.9%) than the rupture rate for the aneurysm at other locations (7.9%). (6) Traumatic pseudoaneurysms on the dACA were observed in two cases, and one of these cases showed massive ICH shortly after head trauma. (7) Twenty-six out of 30 patients (86.7%) showed a good outcome with a mortality rate of 3.3%. CONCLUSIONS: The dACA aneurysms are uncommon and they have unique characteristics compared to intracerebral aneurysms at other sites. Especially, a very careful surgical approach must be used for dACA aneurysms because they have a higher rate of intraoperative rupture. Yet the surgical outcome for dACA patients was good for the ruptured or unruptured aneurysm cases in our study. Therefore, dACA aneurysms have to be treated with considering their special characteristics.

Interhemispheric Approach for Intracranial Aneurysms / 대한뇌혈관학회지

The author describes the basic and standard operative method of interhemispheric(IH) approach for intracranial aneurysms especially aneurysm in anterior cerebral artery territory.Though most neurosurgeons prefer to pterional approach for anterior communicating artery aneurysm, some neurosurgeons select IH approach routinely for this aneurysm because of least brain retraction and excellent anatomical orientation with this approach. But IH approach should be chosen for distal anterior cerebral artery aneurysms and certain cases of anterior communicating artery aneurysms such as high positioned aneurysm or aneurysm with significant hematoma at frontal lobe. interhemispheric approach.

Surgical Treatment of Distal Anterior Cerebral Artery Aneurysms

The incidence of the distal anterior cerebral artery(DACA) aneurysm comprises about 2-6% of all intracerebral aneurysms. Because of the low incidence, unique anatomies of the distal anterior cerebral arteries and some technical difficulties in surgery, these aneurysms present such challenge to neurosurgeons. Presently, early surgery using interhemispheric approach is preferred. The auhtors experienced six patients with DACA aneurysms in 130 consecutive intracerebral aneurysms surgically treated between May. 1994 and Dec. 1997. The patients received operations within five days from the ictus, except one patient because of symptomatic vasospasm. The surgical approaches were all unilateral interhemispheric approaches. During the operations, infusion of large amount of mannitol and CSF volume removal were applied, although there were few difficulties in the interhemispheric dissections, the outcomes of the patients were excellent in three, good in three. The authors suggest that early operative interventions using unilateral interhemispheric approach without generous craniotomy can improve the outcomes of the patients with ruptured DACA aneurysm.

Four Cases of Surgically Managed Distal Anterior Cerebral Artery Aneurysm

A series of 4 patients with aneurysm of distal anterior cerebral artery(DACA), operated with microtechniques, is reviewed. Because the incidence of aneurysms in this location was only 2 to 4% of that of total aneurysm, little expericences on surgical management of this aneurysm have been reported. An aneurysm in this location is difficult to approach surgically because of their multiplicity, characteristically broad and sclerotic base, with small subarachnoid space in the interhemispheric fissure. We surgically treated DACA aneurysms of 4 cases through the interhemispheric approach via the unilateral frontal paramedian craniotomy on the nondominant side.

Microsurgical Treatment of Distal Anterior Cerebral Artery Aneurysm

Between Jan. 1983 and Dec. 1990, 17 Patients with distal anterior cerebral artery(DACA) aneurysms were admitted to our institute and underwent microsurgical neck clipping of their aneurysms. This group comprised 3.7% of the 437 aneurysms managed surgically during this period. There were 11 females and 6 males. The mean age was 48.5 years. Most of DACA aneurysms were located at the genu portion of the anterior cerebral artery. Three cases were at the proximal protion of A2 close to the anterior communicating artery. Two cases were at the dista pericallosal artery and distal callosomarginal artery. Eight patients had additional vascular anomalies documented by angiography such as multiple aneurysms, azygos DACA and duplication of DACA. Direct neck clipping was possible in all cases through the interhemispheric approach or the frontotemporal approach according to the location. For the interhemispheric apporach preoperative evaluation of the exact location and direction of the aneurysms on the angiogram was important for operative planning. The surgical outcome was good or excellent without any neurological deficits in 17 of the cases. Operative management, clinical features and incidence of vascular anomalies associated with DACA aneurysms are discussed.

Surgical Management of the Distal Anterior Cerebral Artery Aneurysms

The authors described different type of aneurysms in the distal anterior cerebral artery(DACA), which is difficult to approach surgically. there are anomalies of distal anterior cerebral artery in about one fourth and narrow space, which made more careful surgical dissection. We experienced 7 cases of DACA aneurysm, 6 cases of which were treated surgically through the interhemispheric approach via the unilateral frontal paramedian craniotomy on the non-dominant side. Surgical results were anatomical complexities, modern microsurgical technique aided by microscope make the approach more exactly and safely.

Subdural Hematoma Due to Ruptured Intracerebral Aneurysm

An intracerebral aneurysm usually bleeds into the subarachnoid space in addition it may also rupture into the subdural space or into the brain, and it is reported that approximately 2-8 percent of all ruptured aneurysm have an associated subdural hematoma. We had experienced 4 cases of subdural hematoma following ruptured intracerebral saccular aneurysm from 1983 to 1985. They were distal anterior cerebral artery aneurysm and middle cerebral artery aneurysm, and 2 cases of anterior communicating artery aneurysm. There were no relationship between the amount of subdural hematoma and clinical course. With a view to the clinical course, 3 cases were acute, and one was chronic.