PMCC PMCC

Search tips
Search criteria

Advanced
Results 1-25 (642961)

Clipboard (0)
None

Related Articles

1.  Superciliary Keyhole Approach for Unruptured Anterior Circulation Aneurysms: Surgical Technique, Indications, and Contraindications 
Neurosurgeons have been trying to reduce surgical invasiveness by applying minimally invasive keyhole approaches. Therefore, this paper clarifies the detailed surgical technique, its limitations, proper indications, and contraindications for a superciliary keyhole approach as a minimally invasive modification of a pterional approach. Successful superciliary keyhole surgery for unruptured aneurysms requires an understanding of the limitations and the use of special surgical techniques. Essentially, this means the effective selection of surgical indications, usage of the appropriate surgical instruments with a tubular shaft, and refined surgical techniques, including straightforward access to the aneurysm, clean surgical dissection, and the application of clips with an appropriate configuration. A superciliary keyhole approach allows unruptured anterior circulation aneurysms to be clipped safely, rapidly, and less invasively on the basis of appropriate surgical indications.
doi:10.3340/jkns.2014.56.5.371
PMCID: PMC4272993  PMID: 25535512
Cerebral aneurysm; Contraindications; Minimally invasive surgical procedures; Surgical technique
2.  Coil Embolization for Intracranial Aneurysms 
Executive Summary
Objective
To determine the effectiveness and cost-effectiveness of coil embolization compared with surgical clipping to treat intracranial aneurysms.
The Technology
Endovascular coil embolization is a percutaneous approach to treat an intracranial aneurysm from within the blood vessel without the need of a craniotomy. In this procedure, a microcatheter is inserted into the femoral artery near the groin and navigated to the site of the aneurysm. Small helical platinum coils are deployed through the microcatheter to fill the aneurysm, and prevent it from further expansion and rupture. Health Canada has approved numerous types of coils and coil delivery systems to treat intracranial aneurysms. The most favoured are controlled detachable coils. Coil embolization may be used with other adjunct endovascular devices such as stents and balloons.
Background
Intracranial Aneurysms
Intracranial aneurysms are the dilation or ballooning of part of a blood vessel in the brain. Intracranial aneurysms range in size from small (<12 mm in diameter) to large (12–25 mm), and to giant (>25 mm). There are 3 main types of aneurysms. Fusiform aneurysms involve the entire circumference of the artery; saccular aneurysms have outpouchings; and dissecting aneurysms have tears in the arterial wall. Berry aneurysms are saccular aneurysms with well-defined necks.
Intracranial aneurysms may occur in any blood vessel of the brain; however, they are most commonly found at the branch points of large arteries that form the circle of Willis at the base of the brain. In 85% to 95% of patients, they are found in the anterior circulation. Aneurysms in the posterior circulation are less frequent, and are more difficult to treat surgically due to inaccessibility.
Most intracranial aneurysms are small and asymptomatic. Large aneurysms may have a mass effect, causing compression on the brain and cranial nerves and neurological deficits. When an intracranial aneurysm ruptures and bleeds, resulting in a subarachnoid hemorrhage (SAH), the mortality rate can be 40% to 50%, with severe morbidity of 10% to 20%. The reported overall risk of rupture is 1.9% per year and is higher for women, cigarette smokers, and cocaine users, and in aneurysms that are symptomatic, greater than 10 mm in diameter, or located in the posterior circulation. If left untreated, there is a considerable risk of repeat hemorrhage in a ruptured aneurysm that results in increased mortality.
In Ontario, intracranial aneurysms occur in about 1% to 4% of the population, and the annual incidence of SAH is about 10 cases per 100,000 people. In 2004-2005, about 660 intracranial aneurysm repairs were performed in Ontario.
Treatment of Intracranial Aneurysms
Treatment of an unruptured aneurysm attempts to prevent the aneurysm from rupturing. The treatment of a ruptured intracranial aneurysm aims to prevent further hemorrhage. There are 3 approaches to treating an intracranial aneurysm.
Small, asymptomatic aneurysms less than 10 mm in diameter may be monitored without any intervention other than treatment for underlying risk factors such as hypertension.
Open surgical clipping, involves craniotomy, brain retraction, and placement of a silver clip across the neck of the aneurysm while a patient is under general anesthesia. This procedure is associated with surgical risks and neurological deficits.
Endovascular coil embolization, introduced in the 1990s, is the health technology under review.
Literature Review
Methods
The Medical Advisory Secretariat searched the International Health Technology Assessment (INAHTA) Database and the Cochrane Database of Systematic Reviews to identify relevant systematic reviews. OVID Medline, Medline In-Process and Other Non-Indexed Citations, and Embase were searched for English-language journal articles that reported primary data on the effectiveness or cost-effectiveness of treatments for intracranial aneurysms, obtained in a clinical setting or analyses of primary data maintained in registers or institutional databases. Internet searches of Medscape and manufacturers’ databases were conducted to identify product information and recent reports on trials that were unpublished but that were presented at international conferences. Four systematic reviews, 3 reports on 2 randomized controlled trials comparing coil embolization with surgical clipping of ruptured aneurysms, 30 observational studies, and 3 economic analysis reports were included in this review.
Results
Safety and Effectiveness
Coil embolization appears to be a safe procedure. Complications associated with coil embolization ranged from 8.6% to 18.6% with a median of about 10.6%. Observational studies showed that coil embolization is associated with lower complication rates than surgical clipping (permanent complication 3-7% versus 10.9%; overall 23% versus 46% respectively, p=0.009). Common complications of coil embolization are thrombo-embolic events (2.5%–14.5%), perforation of aneurysm (2.3%–4.7%), parent artery obstruction (2%–3%), collapsed coils (8%), coil malposition (14.6%), and coil migration (0.5%–3%).
Randomized controlled trials showed that for ruptured intracranial aneurysms with SAH, suitable for both coil embolization and surgical clipping (mostly saccular aneurysms <10 mm in diameter located in the anterior circulation) in people with good clinical condition:Coil embolization resulted in a statistically significant 23.9% relative risk reduction and 7% absolute risk reduction in the composite rate of death and dependency compared to surgical clipping (modified Rankin score 3–6) at 1-year.
The advantage of coil embolization over surgical clipping varies widely with aneurysm location, but endovascular treatment seems beneficial for all sites.
There were less deaths in the first 7 years following coil embolization compared to surgical clipping (10.8% vs 13.7%). This survival benefit seemed to be consistent over time, and was statistically significant (log-rank p= 0.03).
Coil embolization is associated with less frequent MRI-detected superficial brain deficits and ischemic lesions at 1-year.
The 1- year rebleeding rate was 2.4% after coil embolization and 1% for surgical clipping. Confirmed rebleeding from the repaired aneurysm after the first year and up to year eight was low and not significantly different between coil embolization and surgical clipping (7 patients for coil embolization vs 2 patients for surgical clipping, log-rank p=0.22).
Observational studies showed that patients with SAH and good clinical grade had better 6-month outcomes and lower risk of symptomatic cerebral vasospasm after coil embolization compared to surgical clipping.
For unruptured intracranial aneurysms, there were no randomized controlled trials that compared coil embolization to surgical clipping. Large observational studies showed that:
The risk of rupture in unruptured aneurysms less than 10 mm in diameter is about 0.05% per year for patients with no pervious history of SAH from another aneurysm. The risk of rupture increases with history of SAH and as the diameter of the aneurysm reaches 10 mm or more.
Coil embolization reduced the composite rate of in hospital deaths and discharge to long-term or short-term care facilities compared to surgical clipping (Odds Ratio 2.2, 95% CI 1.6–3.1, p<0.001). The improvement in discharge disposition was highest in people older than 65 years.
In-hospital mortality rate following treatment of intracranial aneurysm ranged from 0.5% to 1.7% for coil embolization and from 2.1% to 3.5% for surgical clipping. The overall 1-year mortality rate was 3.1% for coil embolization and 2.3% for surgical clipping. One-year morbidity rate was 6.4% for coil embolization and 9.8% for surgical clipping. It is not clear whether these differences were statistically significant.
Coil embolization is associated with shorter hospital stay compared to surgical clipping.
For both ruptured and unruptured aneurysms, the outcome of coil embolization does not appear to be dependent on age, whereas surgical clipping has been shown to yield worse outcome for patients older than 64 years.
Angiographic Efficiency and Recurrences
The main drawback of coil embolization is its low angiographic efficiency. The percentage of complete aneurysm occlusion after coil embolization (27%–79%, median 55%) remains lower than that achieved with surgical clipping (82%–100%). However, about 90% of coiled aneurysms achieve near total occlusion or better. Incompletely coiled aneurysms have been shown to have higher aneurysm recurrence rates ranging from 7% to 39% for coil embolization compared to 2.9% for surgical clipping. Recurrence is defined as refilling of the neck, sac, or dome of a successfully treated aneurysm as shown on an angiogram. The long-term clinical significance of incomplete occlusion following coil embolization is unknown, but in one case series, 20% of patients had major recurrences, and 50% of these required further treatment.
Long-Term Outcomes
A large international randomized trial reported that the survival benefit from coil embolization was sustained for at least 7 years. The rebleeding rate between year 2 and year 8 following coil embolization was low and not significantly different from that of surgical clipping. However, high quality long-term angiographic evidence is lacking. Accordingly, there is uncertainty about long-term occlusion status, coil durability, and recurrence rates. While surgical clipping is associated with higher immediate procedural risks, its long-term effectiveness has been established.
Indications and Contraindications
Coil embolization offers treatment for people at increased risk for craniotomy, such as those over 65 years of age, with poor clinical status, or with comorbid conditions. The technology also makes it possible to treat surgical high-risk aneurysms.
Not all aneurysms are suitable for coil embolization. Suitability depends on the size, anatomy, and location of the aneurysm. Aneurysms more than 10 mm in diameter or with an aneurysm neck greater than or equal to 4 mm are less likely to achieve total occlusion. They are also more prone to aneurysm recurrences and to complications such as coil compaction or parent vessel occlusion. Aneurysms with a dome to neck ratio of less than 1 have been shown to have lower obliteration rates and poorer outcome following coil embolization. Furthermore, aneurysms in the middle cerebral artery bifurcation are less suitable for coil embolization. For some aneurysms, treatment may require the use of both coil embolization and surgical clipping or adjunctive technologies, such as stents and balloons, to obtain optimal results.
Diffusion
Information from 3 countries indicates that coil embolization is a rapidly diffusing technology. For example, it accounted for about 40% of aneurysm treatments in the United Kingdom.
In Ontario, coil embolization is an insured health service, with the same fee code and fee schedule as open surgical repair requiring craniotomy. Other costs associated with coil embolization are covered under hospitals’ global budgets. Utilization data showed that in 2004-2005, coil embolization accounted for about 38% (251 cases) of all intracranial aneurysm repairs in the province. With the 2005 publication of the positive long-term survival data from the International Subarachnoid Aneursym Trial, the pressure for diffusion will likely increase.
Economic Analysis
Recent economic studies show that treatment of unruptured intracranial aneurysms smaller than 10 mm in diameter in people with no previous history of SAH, either by coil embolization or surgical clipping, would not be effective or cost-effective. However, in patients with aneurysms that are greater than or equal to 10 mm or symptomatic, or in patients with a history of SAH, treatment appears to be cost-effective.
In Ontario, the average device cost of coil embolization per case was estimated to be about $7,500 higher than surgical clipping. Assuming that the total number of intracranial aneurysm repairs in Ontario increases to 750 in the fiscal year of 2007, and assuming that up to 60% (450 cases) of these will be repaired by coil embolization, the difference in device costs for the 450 cases (including a 15% recurrence rate) would be approximately $3.8 million. This figure does not include capital costs (e.g. $3 million for an angiosuite), additional human resources required, or costs of follow-up. The increase in expenditures associated with coil embolization may be offset partially, by shorter operating room times and hospitalization stays for endovascular repair of unruptured aneurysms; however, the impact of these cost savings is probably not likely to be greater than 25% of the total outlay since the majority of cases involve ruptured aneurysms. Furthermore, the recent growth in aneurysm repair has predominantly been in the area of coil embolization presumably for patients for whom surgical clipping would not be advised; therefore, no offset of surgical clipping costs could be applied in such cases. For ruptured aneurysms, downstream cost savings from endovascular repair are likely to be minimal even though the savings for individual cases may be substantial due to lower perioperative complications for endovascular aneurysm repair.
Guidelines
The two Guidance documents issued by the National Institute of Clinical Excellence (UK) in 2005 support the use of coil embolization for both unruptured and ruptured (SAH) intracranial aneurysms, provided that procedures are in place for informed consent, audit, and clinical governance, and that the procedure is performed in specialist units with expertise in the endovascular treatment of intracranial aneurysms.
Conclusion
For people in good clinical condition following subarachnoid hemorrhage from an acute ruptured intracranial aneurysm suitable for either surgical clipping or endovascular repair, coil embolization results in improved independent survival in the first year and improved survival for up to seven years compared to surgical clipping. The rebleeding rate is low and not significantly different between the two procedures after the first year. However, there is uncertainty regarding the long-term occlusion status, durability of the stent graft, and long-term complications.
For people with unruptured aneurysms, level 4 evidence suggests that coil embolization may be associated with comparable or less mortality and morbidity, shorter hospital stay, and less need for discharge to short-term rehabilitation facilities. The greatest benefit was observed in people over 65 years of age. In these patients, the decision regarding treatment needs to be based on the assessment of the risk of rupture against the risk of the procedure, as well as the morphology of the aneurysm.
In people who require treatment for intracranial aneurysm, but for whom surgical clipping is too risky or not feasible, coil embolization provides survival benefits over surgical clipping, even though the outcomes may not be as favourable as in people in good clinical condition and with small aneurysms. The procedure may be considered under the following circumstances provided that the aneurysm is suitable for coil embolization:
Patients in poor/unstable clinical or neurological state
Patients at high risk for surgical repair (e.g. people>age 65 or with comorbidity), or
Aneurysm(s) with poor accessibility or visibility for surgical treatment due to their location (e.g. ophthalmic or basilar tip aneurysms)
Compared to small aneurysms with a narrow neck in the anterior circulation, large aneurysms (> 10 mm in diameter), aneurysms with a wide neck (>4mm in diameter), and aneurysms in the posterior circulation have lower occlusion rates and higher rate of hemorrhage when treated with coil embolization.
The extent of aneurysm obliteration after coil embolization remains lower than that achieved with surgical clipping. Aneurysm recurrences after successful coiling may require repeat treatment with endovascular or surgical procedures. Experts caution that long-term angiographic outcomes of coil embolization are unknown at this time. Informed consent for and long-term follow-up after coil embolization are recommended.
The decision to treat an intracranial aneurysm with surgical clipping or coil embolization needs to be made jointly by the neurosurgeon and neuro-intervention specialist, based on the clinical status of the patient, the size and morphology of the aneurysm, and the preference of the patient.
The performance of endovascular coil embolization should take place in centres with expertise in both neurosurgery and endovascular neuro-interventions, with adequate treatment volumes to maintain good outcomes. Distribution of the technology should also take into account that patients with SAH should be treated as soon as possible with minimal disruption.
PMCID: PMC3379525  PMID: 23074479
3.  Analysis of Clip-induced Ischemic Complication of Anterior Choroidal Artery Aneurysms 
Objective
The surgical approach is typically similar to those used for other supraclinoid internal carotid artery (ICA) lesions. However, the surgical clipping of this aneurysm is complicated and as a result, can result in postoperative ischemic complications. We studied to clarify the clip-induced ischemic complication risk of AChA aneurysm and to get the benefits for helping decision making.
Methods
We retrospectively investigated 53 cases (4.0%) of AchA aneurysm treated surgically. We divided the AChA aneurysm to 3 subtype according to the origin of aneurysmal neck; A type originating from the AChA itself, J type from junction of AChA and ICA, and I type from the ICA itself. We evaluated brain CT about 1 week post-operative day to confirm the low density in AChA territory.
Results
Ruptured aneurysm was 26 cases and unruptured aneurysm 27 cases. The aneurysmal subtype of A, J, and I was 13, 17, and 23 cases. Of the 53 cases who performed surgical neck clipping, twelve (22.6%) had postoperative AChA distribution infarcts. Increased infarct after neck clipping had statistic significance in non-I subtype (p=0.005).
Conclusion
It is easy to classify as "easy" surgery. But surgery for AChA aneurysms carries with it a significant risk of postoperative stroke. Don't always stick to clipping only, especially in non-I type of incidental small aneurysm, which has high risk of post-clip ischemic complications.
doi:10.3340/jkns.2008.43.3.131
PMCID: PMC2588238  PMID: 19096619
Anterior choroidal artery infarction; Clip; Intracranial aneurysm
4.  The Avoidance of Microsurgical Complications in the Extradural Anterior Clinoidectomy to Paraclinoid Aneurysms 
Objective
Paraclinoid segment internal carotid artery (ICA) aneurysms have historically been a technical challenge for neurovascular surgeons. The development of microsurgical approach, advances in surgical techniques, and endovascular procedures have improved the outcome for paraclinoid aneurysms. However, many authors have reported high complication rates from microsurgical treatments. Therefore, the present study reviews the microsurgical complications of the extradural anterior clinoidectomy for treating paraclinoid aneurysms and investigates the prevention and management of observed complications.
Methods
Between January 2004 and April 2008, 22 patients with 24 paraclinoid aneurysms underwent microsurgical direct clipping by a cerebrovascular team at a regional neurosurgical center. Microsurgery was performed via an ipsilateral pterional approach with extradural anterior clinoidectomy. We retrospectively reviewed patients' medical charts, office records, radiographic studies, and operative records.
Results
In our series, the clinical outcomes after an ipsilateral pterional approach with extradural anterior clinoidectomy for paraclinoid aneurysms were excellent or good (Glasgows Outcome Scale : GOS 5 or 4) in 87.5% of cases. The microsurgical complications related directly to the extradural anterior clinoidectomy included transient cranial nerve palsy (6), cerebrospinal fluid leak (1), worsened change in vision (1), unplanned ICA occlusion (1), and epidural hematoma (1). Only one of the complications resulted in permanent morbidity (4.2%), and none resulted in death.
Conclusion
Although surgical complications are still reported to occur more frequently for the treatment of paraclinoid aneurysms, the permanent morbidity and mortality resulting from a extradural anterior clinoidectomy in our series were lower than previously reported. Precise anatomical knowledge combined with several microsurgical tactics can help to achieve good outcomes with minimal complications.
doi:10.3340/jkns.2010.48.3.199
PMCID: PMC2966719  PMID: 21082045
Extradural anterior clinoidectomy; Paraclinoid aneurysm; Clinical outcomes; Surgical complications
5.  Comparative Analysis of the Mini-pterional and Supraorbital Keyhole Craniotomies for Unruptured Aneurysms with Numeric Measurements of Their Geometric Configurations 
Objective
Keyhole craniotomy is a modification of pterional craniotomy that allows for use of a minimally invasive approach toward cerebral aneurysms. Currently, mini-pterional (MPKC) and supraorbital keyhole craniotomies (SOKC) are commonly used. In this study, we measured and compared the geometric configurations of surgical exposure provided by MPKC and SOKC.
Methods
Nine patients underwent MPKC and four underwent SOKC. Their postoperative contrast-enhanced brain computed tomographic scans were evaluated. The transverse and longitudinal diameters and areas of exposure were measured. The locations of the anterior communicating artery, bifurcation of the middle cerebral artery (MCAB), and the internal carotid artery (ICA) terminal were identified, and the working angles and depths for these targets were measured.
Results
No significant differences in the transverse diameters of exposure were observed between MPKC and SOKC. However, the longitudinal diameters and the areas were significantly larger, by 1.5 times in MPKC. MPKC provided larger operable working angles for the targets. The angles by MPKC, particularly for the MCAB, reached up to 1.9-fold of those by SOKC. Greater working depths were required in order to reach the targets by SOKC, and the differences were the greatest in the MCAB by 1.6-fold.
Conclusion
MPKC provides larger exposure than SOKC with a similar length of skin incision. MPKC allows for use of a direct transsylvian approach, and exposes the target in a wide working angle within a short distance. Despite some limitations in exposure, SOKC is suitable for a direct subfrontal approach, and provides a more anteromedial and basal view. MCAB and posteriorly directing ICA terminal aneurysms can be good candidates for MPKC.
doi:10.7461/jcen.2013.15.1.5
PMCID: PMC3625819  PMID: 23593599
Cerebral aneurysm; Craniotomy; Minimally invasive; Mini-pterional; Supraorbital; Surgical exposure
6.  Result of Extracranial-Intracranial Bypass Surgery in the Treatment of Complex Intracranial Aneurysms : Outcomes in 15 Cases 
Objective
The standard treatment strategy of intracranial aneurysms includes either endovascular coiling or microsurgical clipping. In certain situations such as in giant or dissecting aneurysms, bypass surgery followed by proximal occlusion or trapping of parent artery is required.
Methods
The authors assessed the result of extracranial-intracranial (EC-IC) bypass surgery in the treatment of complex intracranial aneurysms in one institute between 2003 and 2007 retrospectively to propose its role as treatment modality. The outcomes of 15 patients with complex aneurysms treated during the last 5 years were reviewed. Six male and 9 female patients, aged 14 to 76 years, presented with symptoms related to hemorrhage in 6 cases, transient ischemic attack (TIA) in 2 unruptured cases, and permanent infarction in one, and compressive symptoms in 3 cases. Aneurysms were mainly in the internal carotid artery (ICA) in 11 cases, middle cerebral artery (MCA) in 2, posterior cerebral artery (PCA) in one and posterior inferior cerebellar artery (PICA) in one case.
Results
The types of aneurysms were 8 cases of large to giant size aneurysms, 5 cases of ICA blood blister-like aneurysms, one dissecting aneurysm, and one pseudoaneurysm related to trauma. High-flow bypass surgery was done in 6 cases with radial artery graft (RAG) in five and saphenous vein graft (SVG) in one. Low-flow bypass was done in nine cases using superficial temporal artery (STA) in eight and occipital artery (OA) in one case. Parent artery occlusion was performed with clipping in 9 patients, with coiling in 4, and with balloon plus coil in 1. Direct aneurysm clip was done in one case. The follow up period ranged from 2 to 48 months (mean 15.0 months). There was no mortality case. The long-term clinical outcome measured by Glasgow outcome scale (GOS) showed good or excellent outcome in 13/15. The overall surgery related morbidity was 20% (3/15) including 2 emergency bypass surgeries due to unexpected parent artery occlusion during direct clipping procedure. The short-term postoperative bypass graft patency rates were 100% but the long-term bypass patency rates were 86.7% (13/15). Nonetheless, there was no bypass surgery related morbidity due to occlusion of the graft.
Conclusion
Revascularization technique is a pivotal armament in managing complex aneurysms and scrupulous prior planning is essential to successful outcomes.
doi:10.3340/jkns.2008.44.4.228
PMCID: PMC2588312  PMID: 19096682
Cerebral aneurysm; Extracranial-intracranial bypass; Outcomes
7.  Internal Carotid Artery Reconstruction Using Multiple Fenestrated Clips for Complete Occlusion of Large Paraclinoid Aneurysms 
Objective
Although surgical techniques for clipping paraclinoid aneurysms have evolved significantly in recent times, direct microsurgical clipping of large and giant paraclinoid aneurysms remains a formidable surgical challenge. We review here our surgical experiences in direct surgical clipping of large and giant paraclinoid aneurysms, especially in dealing with anterior clinoidectomy, distal dural ring resection, optic canal unroofing, clipping techniques, and surgical complications.
Methods
Between September 2001 and February 2012, we directly obliterated ten large and giant paraclinoid aneurysms. In all cases, tailored orbito-zygomatic craniotomies with extradural and/or intradural clinoidectomy were performed. The efficacy of surgical clipping was evaluated with postoperative digital subtraction angiography and computed tomographic angiography.
Results
Of the ten cases reported, five each were of ruptured and unruptured aneurysms. Five aneurysms occurred in the carotid cave, two in the superior hypophyseal artery, two in the intracavernous, and one in the posterior wall. The mean diameter of the aneurysms sac was 18.8 mm in the greatest dimension. All large and giant paraclinoid aneurysms were obliterated with direct neck clipping without bypass. With the exception of the one intracavenous aneurysm, all large and giant paraclinoid aneurysms were occluded completely.
Conclusion
The key features of successful surgical clipping of large and giant paraclinoid aneurysms include enhancing exposure of proximal neck of aneurysms, establishing proximal control, and completely obliterating aneurysms with minimal manipulation of the optic nerve. Our results suggest that internal carotid artery reconstruction using multiple fenestrated clips without bypass may potentially achieve complete occlusion of large paraclinoid aneurysms.
doi:10.3340/jkns.2013.54.6.477
PMCID: PMC3921274  PMID: 24527189
Clinoidectomy; Orbito-zygomatic craniotomy; Paraclinoid aneurysm; Large and giant; Microsurgical clipping
8.  Pterional-subolfactory Approach for Treatment of High Positioned Anterior Communicating Artery Aneurysms 
Objective
The purpose of this study is to compare the surgical outcomes of pterional-subolfactory approach for the high positioned anterior communicating artery (ACoA) aneurysm with the conventional pterional approach.
Methods
Between February 2005 and December 2012, 463 ACoA aneurysms were surgically treated in our institution. Forty eight high positioned ACoA aneurysms were treated with pterional-subolfactory or conventional pterional approach. High positioned ACoA aneurysms were defined as aneurysms located higher than 10 mm above the anterior clinoid process. Pterional-subolfactory approach is a procedure including dissection of olfactory tract and resection of the gyrus rectus inferior and medial to the olfactory tract. Thirty-four of the 48 cases were treated with pterional-subolfactory approach and 14 were treated conventionally.
Results
There were 2 postoperative cerebral infarction with the conventional pterional approach, but none with the pterional-subolfactory approach group (p = 0.026). Postoperative digital subtraction angiography revealed significant remnant aneurysm in the conventional pterional approach group. All patients with unruptured aneurysms had good clinical outcomes with Glasgow outcome score of 5. Among ruptured ACoA aneurysm patients, 2 patients with conventional pterional approach had postoperative cerebral infarctions but permanent neurologic deficit was found in only 1 patient. Three patients treated with the pterional-subolfactory approach, who had preoperative ruptured aneurysms had poor clinical outcomes. The mean operation time for the conventional pterional approach was 58 minutes longer than for the pterional-subolfactory approach (p = 0.001).
Conclusion
We concluded that pterional-subolfactory approach is highly preferable for cases of high positioned ACoA aneurysm, giving a wide and effective operation view.
doi:10.7461/jcen.2013.15.3.177
PMCID: PMC3804655  PMID: 24167797
Subolfactory; Anterior communicating aneurysm
9.  Surgical Results of Unruptured Intracranial Aneurysms in the Elderly : Single Center Experience in the Past Ten Years 
Objective
As medical advances have increased life expectancy, it has become imperative to develop specific treatment strategies for intracranial aneurysms in the elderly. We therefore analyzed the clinical characteristics and outcomes of the treatment of unruptured intracranial aneurysms in patients older than 70 years.
Methods
We retrospectively reviewed the medical records and results of neuroimaging modalities on 54 aneurysms of 48 consecutive patients with unruptured intracranial aneurysms. (mean±SD age, 72.11±1.96 years; range, 70-78 years) who underwent surgical clipping over 10 years (May 1999 to June 2010).
Results
Of the 54 aneurysms, 22 were located in the internal carotid artery, 19 in the middle cerebral artery, 12 in the anterior cerebral artery, and 1 in the superior cerebellar artery. Six patients had multiple aneurysms. Aneurysm size ranged from 3 mm to 17 mm (mean±SD, 6.82±3.07 mm). Fifty of the 54 aneurysms (92.6%) were completely clipped. Three-month outcomes were excellent in 50 (92.6%) aneurysms and good and poor in 2 each (3.7%), with 1 death (2.0%). Procedure-related complications occurred in 7 aneurysms (13.0%), with 2 (3.7%) resulting in permanent neurological deficits, including death. No postoperative subarachnoid hemorrhage occurred during follow-up. The cumulative rates of stroke- or death-free survival at 5 and 10 years were 100% and 78%, respectively.
Conclusion
Surgical clipping of unruptured intracranial aneurysms in elderly group could get it as a favorable outcome in well selected cases.
doi:10.3340/jkns.2011.49.6.329
PMCID: PMC3158474  PMID: 21887389
Unruptured intracranial aneurysm; Surgical clipping; Elderly; Outcome
10.  Surgical Treatment of Unruptured Intracranial Middle Cerebral Artery Aneurysms: Angiographic and Clinical Outcomes in 143 Aneurysms 
Objective
The purpose of this study was to determine the outcomes of surgical clipping in patients with unruptured middle cerebral artery (MCA) aneurysms.
Methods
A retrospective single-center database of 125 consecutive patients with 143 small MCA aneurysms (< 10 mm) who underwent surgical clipping was reviewed from January 2007 to December 2010. Clinical outcomes were assessed based on surgery-related complications and follow-up (mean: 17 months) using the modified Rankin scale (mRS). Angiographic outcomes were evaluated by conventional angiography (N = 96) or computed tomography angiography (N = 29) at postoperative weeks 1 and 6.
Results
There were no cases of mortality. There were three surgery-related complications (intracranial hemorrhage, meningitis and wound infection, respectively). The hemorrhagic event caused transient neurological deficits. All patients showed good clinical outcomes during follow-up (mRS 0-1). There was angiographic evidence of complete occlusion in 137 aneurysms (95.8%), a small residual neck in three aneurysms (2.2%) and partial for three aneurysms. In the three cases with partial clipping, the decision was made preoperatively to leave the residual sac to maintain distal flow, and muscular wrapping was performed.
Conclusion
Our study demonstrates that surgical clipping of unruptured small MCA aneurysms yields favorable clinical and angiographic outcomes. Aneurysmal clipping can be safely recommended for patients with small unruptured MCA aneurysms.
doi:10.7461/jcen.2012.14.4.289
PMCID: PMC3543914  PMID: 23346544
Aneurysm; Middle cerebral artery; Surgical clip; Treatment outcome
11.  Case Report: A Troublesome Ophthalmic Artery Aneurysm 
Objective and Importance When treating large unruptured ophthalmic artery (OA) aneurysms causing progressive blindness, surgical clipping is still the preferred method because aneurysm sac decompression may relieve optic nerve compression. However, endovascular treatment of OA aneurysms has made important progress with the introduction of stents. Although this development is welcomed, it also makes the choice of treatment strategy less straightforward than in the past, with the potential of missteps.
Clinical Presentation A 56-year-old woman presented with a long history of progressive unilateral visual loss and magnetic resonance imaging showing a 20-mm left-sided OA aneurysm.
Intervention Because of her long history of very poor visual acuity, we considered her left eye to be irredeemable and opted for endovascular therapy. The OA aneurysms was treated with stent and coils but continued to grow, threatening the contralateral eye. Because she failed internal carotid artery (ICA) balloon test occlusion, we performed a high-flow extracranial-intracranial bypass with proximal ICA occlusion in the neck. However, aneurysm growth continued due to persistent circulation through reversed blood flow in distal ICA down to the OA and the cavernous portion of the ICA. Due to progressive loss of her right eye vision, we surgically occluded the ICA proximal to the posterior communicating artery and excised the coiled, now giant, OA aneurysm. This improved her right eye vision, but her left eye was permanently blind.
Conclusion This case report illustrates complications of the endovascular and surgical treatment of a large unruptured OA aneurysm.
doi:10.1055/s-0034-1387187
PMCID: PMC4242818  PMID: 25485220
ophthalmic artery aneurysm; endovascular treatment; neurovascular surgery; complications
12.  Efficacy of Endovascular Surgery for Unruptured Internal Carotid Artery Aneurysms Presenting with Cranial Nerve Symptoms 
Interventional Neuroradiology  2007;13(Suppl 1):163-169.
Summary
Whether endovascular surgery is able to reduce the mass effects of unruptured aneurysms is still controversial, although some reports have suggested efficacy in cases of internal carotidartery aneurysms with cranial nerve palsy. Here we assessed outcome in a series of cases.
Between April 1992 and April 2005, 18 patients with unruptured internal carotid artery aneurysms presenting with cranial nerve palsy were treated by endovascular surgery. The patients were two males and 16 females aged from 19 to 84 (mean 59.6 years). Aneurysms were located in the cavernous portion in 14, at the origin of the ophthalmic artery in one and at the origin of P-com in three. The aneurysms were all embolized using Guglielmi detachable coils, Interlocking detachable coils, Cook's detachable coils or Trufill DSC and detachable Balloons were applied to occlude the proximal parent artery.We analyzed the efficacy of endovascular surgery for such aneurysms retrospectively.
The mean aneurysm size was 21.4 mm and the mean follow-up period was 57.7 months. Palsy of IInd cranial nerve was evident in three patients, of the IIIrd in eight, of the Vth and Vth in one each, and of the VIth in nine. Post embolization occlusion was complete in nine patients and neck remnant in the other seven.
Regarding complications of endovascular surgery, one case (5.6%) showed TIA after embolization. Overall 11 (46%) cranial nerve symptoms showed complete resolution, eight (33%) showed some improvement, and five (21%) were unchanged. In three cases (12.5%), the symptoms worsened after treatment. The shorter the duration of symptoms was a factor predisposing to resolution of symptoms. In complete resolution cases, the timing of treatment after symptoms appeared and the time of complete resolution were in proportion
These results showed that there is no difference in reduction of mass effects between surgical clipping and endovascular surgery for unruptured internal carotid artery aneurysms.With endovascular surgery, the rapidity of treatment after symptoms is the most important factor for successful results.
PMCID: PMC3345461  PMID: 20566096
internal carotid artery aneurysm, cranial nerve palsy, endovascular surgery
13.  Comparison between Lateral Supraorbital Approach and Pterional Approach in the Surgical Treatment of Unruptured Intracranial Aneurysms 
Objective
The lateral supraorbital (LSO) approach is a modified method of the classic pterional approach and it has advantages of short skin incision and small craniotomy compared with the pterional approach. This study was designed to compare the two approaches in the surgical treatment of unruptured intracranial aneurysms.
Methods
We retrospectively reviewed 122 patients with 137 unruptured intracranial aneurysms treated by clipping, from July 2009 to April 2011. Between August 2010 and April 2011, 61 patients were treated by clipping via the lateral supraorbital approach and the same number of patients treated by clipping via the pterional approach were retrospectively enrolled. We analyzed the two groups and compared demographic, radiologic and clinical variables.
Results
The mean age of patients in the two groups was 54.6 years (LSO group) and 55.7 years (Pterion group). The mean duration of hospitalization was shorter in the LSO group than in the Pterion group (7.9 days vs. 9.0 days, p=0.125) and the mean operation time was also significantly shorter in the LSO group (117.1 minutes vs. 164.3 minutes, p<0.001). Furthermore, the mean craniotomy area was much smaller in the LSO group (1275.4 mm2 vs. 2858.9 mm2, p<0.001). The two groups showed similar distributions of aneurysm location and postoperative complications.
Conclusion
The lateral supraorbital approach for the clipping of unruptured intracranial aneurysm could be a good alternative to the classic pterional approach.
doi:10.3340/jkns.2012.51.6.334
PMCID: PMC3424172  PMID: 22949961
Supraorbital approach; Pterional approach; Aneurysm; Clipping
14.  Life-threatening allergic vasculitis after clipping an unruptured aneurysm: Case report, weighing the risk of nickel allergy 
Surgical Neurology International  2014;5(Suppl 4):S161-S164.
Background:
This case report represents one of the estimated 17,000 aneurysms clipped annually in the United States, often with nickel-containing clips. The authors highlight the development of life-threatening allergic vasculitis in a 33-year-old woman after aneurysm clipping.
Case Description:
After suffering subarachnoid hemorrhage, the patient had coil embolization at another facility for rupture of a right internal carotid artery (ICA) aneurysm. An incidental finding, an unruptured left posterior communicating artery aneurysm unamenable to coiling, was then successfully clipped via a left pterional craniotomy. Arriving in our emergency department 11 days later, she progressively declined during the next weeks, facing deteriorating clinical status (i.e. seizures) and additional infarctions in the left frontal lobe, midline shift, and new infarctions in the bilateral frontal lobe, right sylvian, right insular regions, and posterior cerebral artery distribution. During decompressive surgery, biopsy findings raised the possibility of lymphocytic vasculitis; consultations with rheumatology, allergy, and immunology specialists identified that our patient had a nickel allergy. After reoperation to replace the nickel-containing clip with one of a titanium alloy, the patient had an uncomplicated postoperative course and was discharged 6 days later to a rehabilitation facility.
Conclusions:
Nickel-related allergies are more common than appreciated, affecting up to 10% of patients. Fortunately, severe reactions are rare; nevertheless, vascular neurosurgeons should be aware of this potential complication when using cobalt alloy aneurysms clips. The use of titanium alloy clips eliminates this risk.
doi:10.4103/2152-7806.134813
PMCID: PMC4109169  PMID: 25071940
Complication; nickel allergy; nickel sensitization
15.  Multimodal Treatment for Complex Intracranial Aneurysms: Clinical Research 
Objective
For patients with giant or dissecting aneurysm, multimodal treatment consisting extracranial-intracranial bypass surgery plus clip or coil for parent artery occlusion may be necessary. In this study, the safety and efficacy of multimodal treatment in 15 patients with complex aneurysms were evaluated retrospectively.
Methods
From January 1995 to June 2007, the authors treated 15 complex aneurysms that were unable to be clipped or coiled. Among them, nine patitents had unruptured aneurysms and 6 had ruptured aneurysms. Aneurysms were located in the internal cerebral artery (ICA) in 11 patients (4 in the dorsal wall, 4 in the terminal ICA, 1 in the paraclinoid, and 2 in the cavernous ICA), in the middle cerebral artery (MCA) in 2, and in the posterior circulation in two patients
Results
Fifteen patients with complex aneurysms were treated with bypass surgery previously. Thirteen patients were treated with external carotid middle cerebral artery (ECA-MCA) anastomosis, and one patient with superficial temporal to posterior cerebral artery (STA-PCA) and another patient with occipital artery to posterior inferior cerebellar artery (OA-PICA) anastomosis. Parent artery occlusion was then performed with a clip in 9 patients, with a coil in 4, with balloon plus coil in one patient. All 15 aneurysms were successfully treated with clip or coil combined with bypass surgery. Follow-up angiograms showed good patency of anastomotic site in 10 out of 11 patients, and perfusion study showed sufficient perfusion in 6 out of 9 patients.
Conclusion
These findings indicate that for patients with complex aneurysms, clip or coil for parent vessel occlusion with additive bypass surgery can successfully exclude the aneurysm from the neurovascular circulatory system.
doi:10.3340/jkns.2008.44.5.314
PMCID: PMC2612569  PMID: 19119468
Aneurysm; Clip; Coil; Bypass
16.  Early and long-term outcome of surgically treated giant internal carotid artery aneurysms—comparison with smaller aneurysms 
Acta Neurochirurgica  2011;153(8):1611-1619.
Background
Internal carotid artery (ICA) is predominant localization of giant intracranial aneurysms (GIAs). The rupture of GIA is supposed to be related to higher risk of poor clinical outcome. Although endovascular techniques are still being developed, they seem to be unsatisfactory in the mean of GIAs.
Methods
Included in the retrospective analysis were 78 giant and 250 smaller surgically treated ICA aneurysms. Exclusion criteria were multiple and blood blister-like aneurysms. Neurological deficit on admission, clinical and radiological presentation, gender, age, segment of ICA, surgical methods, accessory techniques and complications were analyzed. Death rate and short- and long-term outcome of giant aneurysms were compared with smaller aneurysms and risk factors for mortality, unfavorable short- and long-term outcome were determined.
Results
There was no difference in general and surgical complications between ICA aneurysm size groups, as well as in occurrence of newly diagnosed neurological deficit after the operation. There were similar mortality rates, proportion of unfavorable outcome, and low health related quality of life for giant and smaller aneurysms. A 12.2% death rate for all ICA aneurysms was achieved. Trapping method as well as Fisher grades 3 and 4 increased mortality risk in the smaller aneurysm group. No significant factors were related to an unfavorable outcome in the ruptured giant aneurysm group. Patients older than 65, Hunt-Hess grades 4 and 5, Fisher grade 4, and newly diagnosed deficit after operation were connected with unfavorable outcome in the ruptured smaller aneurysm group. Newly diagnosed neurological deficit was also an unfavorable outcome risk factor in both giant and smaller ICA unruptured aneurysms. No difference was noted in long-term health-related quality of life between the giant and smaller ICA groups. Higher age and presence of concomitant disease were independent factors affecting quality of life, although obtained data were incomplete.
Conclusions
The study breaks the stereotype of unfavorable giant ICA aneurysms treatment results. Mortality rate, short- and long-term outcome after the operation of giant and smaller ICA aneurysms are similar. Higher age, patients’ condition at admission, and the amount of extravasated blood and trapping method are poor prognostic factors in patients with smaller ICA aneurysm.
doi:10.1007/s00701-011-1021-6
PMCID: PMC3139865  PMID: 21573809
Internal carotid artery; Intracranial aneurysm; Giant cerebral aneurysm; Outcome; Quality of life
17.  Association between Internal Carotid Artery Morphometry and Posterior Communicating Artery Aneurysm 
Yonsei Medical Journal  2007;48(4):634-638.
Purpose
The goal of this study was to directly measure the association between the internal carotid artery (ICA) morphometry and the presence of ICA-posterior communicating artery (PCOM) aneurysm.
Materials and Methods
The authors intraoperatively measured the length of the supraclinoid ICA because it is impossible to radiologically determine the exact location of the anterior clinoid process. We used an image analyzer with a CT angiogram to measure the angle between the skull midline and the terminal segment of the ICA (ICA angle), as well as the diameter of the ICA. The lengths and diameters of the supraclinoid ICA and the ICA angle were compared among PCOM aneurysms, anterior communicating artery (ACOM) aneurysms, and middle cerebral artery (MCA) bifurcation aneurysms (n = 27 each). Additionally, the lengths and the diameters of M1 and A1 were compared for each aneurysm.
Results
The lengths of the supraclinoid ICA were 11.9 ± 2.3mm. The lengths of the supraclinoid ICA in patients with ICA-PCOM aneurysms (9.7 ± 2.8mm) were shorter than those of patients with ACOM aneurysms (13.8 ± 2.2mm, Student's t-test, p < 0.001) and with MCA bifurcation aneurysms (12.2 ± 1.9 mm, Student's t-test, p < 0.001). The diameters of the supraclinoid ICA and A1 in patients with ACOM aneurysms were larger than those in patients with MCA bifurcation aneurysms (Student's t-test, p < 0.05). There were no significant differences in the lengths of M1 and A1, ICA angle, or diameter of M1 for each aneurysm.
Conclusion
These results suggest that the relatively shorter length of the supraclinoid ICA may be a novel risk factor for the development of ICA-PCOM aneurysm with higher hemodynamic stress.
doi:10.3349/ymj.2007.48.4.634
PMCID: PMC2628055  PMID: 17722235
Internal carotid artery; morphometry; cerebral aneurysm
18.  Microsurgical Experience with Supraorbital Keyhole Operations on Anterior Circulation Aneurysms 
Objective
Conventional pterional approach is a commonly used neurosurgical technique for the treatment of cerebral aneurysms. However, this technique requires more extensive brain exposure than other key hole approaches and is sometimes associated with surgical traumatization or cosmetic problems. The aim of this study was to compare the postoperative outcome between pterional and supraorbital keyhole approaches in the patients with anterior circulation aneurysms.
Methods
The authors reviewed patients with anterior circulation aneurysms who underwent aneurysm clipping via pterional or supraorbital keyhole approach at a single institute over a period of 2 years. Ninety-eight patients harboring 108 aneurysms were included in this study. Various outcomes were recorded, which included clinical grade, cosmetic problems, patients' satisfaction and complications such as chewing discomfort, frontal muscle weakness, hyposmia, infection.
Results
The supraorbital approach exhibited a shorter operation time compared with the pterional approach. Complications such as chewing discomfort occurred less frequently in the supraorbital approach group. Moreover, the cosmetic outcome was significantly better in the supraorbital group than in the pterional group.
Conclusion
The supraorbital keyhole approach reduced intra- and postoperative complications, including chewing discomfort and cosmetic disturbances, compared with the conventional pterional approach.
doi:10.3340/jkns.2009.46.2.103
PMCID: PMC2744018  PMID: 19763211
Pterional approach; Supraorbital approach; Aneurysm; Clipping; Cosmetic outcome
19.  Awake craniotomy for trapping a giant fusiform aneurysm of the middle cerebral artery 
Background:
Giant fusiform aneurysms of the distal middle cerebral artery (MCA) are rare lesions that, because of the absence of an aneurysm neck and the presence of calcified walls and partial thrombosis, can be difficult to clip without sacrificing the parent vessel. Moreover, when the aneurysm is located in the dominant hemisphere, it is not possible to test language and cognitive functions during surgical intervention, making the closure of the parent vessel extremely dangerous.
Case Description:
A 46-year-old woman presented with a one-year history of frontal headache without neurological deficit. A magnetic resonance imaging and an angiography showed a giant fusiform aneurysm of the left M2 tract. Because of the location and the absence of a neck, the aneurysm was considered difficult to coil and not amenable to preoperative balloon occlusion; thus, the patient was a candidate for surgical treatment. After a preoperative psychological evaluation, patient underwent awake craniotomy with the asleep–awake–asleep technique. A standard left pterional approach was performed to expose the internal carotid artery, the MCA and the aneurysm originating from the frontal branch of the MCA. Neurological examination responses remained unchanged during temporary parent artery occlusion, and trapping was successfully performed.
Conclusions:
Awake craniotomy is a useful option in intracranial aneurysm surgery because it permits neurological testing before vessels are permanently clipped or sacrificed. With the asleep–awake–asleep technique, it is possible to perform a standard pterional craniotomy, which allows good exposure of the vascular structures without cerebral retraction.
doi:10.4103/2152-7806.109652
PMCID: PMC3622374  PMID: 23607061
Awake craniotomy; giant aneurysm; middle cerebral artery; pterional approach
20.  “Microbleeding” from intracranial aneurysms: Local hemosiderin deposition identified during microsurgical treatment of unruptured intracranial aneurysms 
Background:
During elective surgery for unruptured aneurysms, we have identified a group of patients with hemosiderin staining of the pial surface immediately adjacent to the aneurysm dome suggesting a remote and unrecognized history of microbleeding from the aneurysm. These cases form the basis for this report.
Methods:
Medical records of 421 unruptured cerebral aneurysm patients treated surgically between January 2003 and September 2010 were retrospectively reviewed. Patients with a history of prior subarachnoid hemorrhage, craniotomy, or significant closed head injury were excluded from review. Records were reviewed for intraoperative descriptions of hemosiderin deposition in the vicinity of the aneurysm as well as history of headaches, time to presentation, comorbidities, aneurysm characteristics, procedures, and radiologic imaging.
Results:
Local hemosiderin staining immediately adjacent to the aneurysm was identified intraoperatively in 13 cases. Each of these patients had a history of remote atypical headache prior to presentation. Eight of these patients (62%) had aneurysms described as particularly “thin-walled” at the time of surgery. Aneurysm locations included the internal carotid artery (ICA) (54%), middle cerebral artery (MCA) (23%), anterior communicating artery (ACOMMA) (15%), and the anterior cerebral artery (ACA) (8%). More than half (54%) of these patients had a history of smoking, while 31% had hypertension, and 23% had a history of alcohol abuse. Dyslipidemia and family history of aneurysms were present in 15% and hypercholesterolemia was noted in one patient (8%).
Conclusion:
We suggest this group of patients had suffered a “microbleed” resulting in local hemosiderin deposition next to the aneurysm. The origins and clinical implications of such microbleeds are unknown and warrant further investigation.
doi:10.4103/2152-7806.127967
PMCID: PMC3994698  PMID: 24778916
Hemosiderin; microbleed; unruptured aneurysms
21.  Treatment of Unruptured Intracranial Aneurysms in South Korea in 2006 : A Nationwide Multicenter Survey from the Korean Society of Cerebrovascular Surgery 
Objective
There have been no clinical studies regarding the epidemiology and treatment outcome for unruptured intracranial aneurysm (UIA) in South Korea yet. Thus, The Korean Society of Cerebrovascular Surgery (KSCVS) decided to evaluate the clinical and epidemiological characteristics, and outcome of the treatment of UIA in 2006, using the nationwide multicenter survey in South Korea.
Methods
A total of 1,696 cases were enrolled retrospectively over one year at 48 hospitals. The following data were obtained from all patients : age, sex, presence of symptoms, location and size of the aneurysm, treatment modality, presence of risk factors for stroke, and the postoperative 30-day morbidity and mortality.
Results
The demographic data showed female predominance and peak age of seventh and sixth decades. Supraclinoid internal carotid artery was the most common site of aneurysms with a mean size of 5.6 mm. Eight-hundred-forty-six patients (49.9%) were treated with clipping, 824 (48.6%) with coiling, and 26 with combined method. The choice of the treatment modalities was related to hospital (p = 0.000), age (p = 0.000), presence of symptom (p = 0.003), and location of aneurysm (p = 0.000). The overall 30-day morbidity and mortality were 7.4% and 0.3%, respectively. The 30-day mortality was 0.4% for clipping and 0.2% for coiling, and morbidity was 8.4% for clipping and 6.3% for coiling. Age (p = 0.010), presence of symptoms (p = 0.034), size (p = 0.000) of aneurysm, and diabetes mellitus (p = 0.000) were significant prognostic factors, while treatment modality was not.
Conclusion
This first nation-wide multicenter survey on UIAs demonstrates the epidemiological and clinical characteristics, outcome and the prognostic factors of the treatment of UIAs in South Korea. The 30-day postoperative outcome for UIAs seems to be reasonable morbidity and mortality in South Korea.
doi:10.3340/jkns.2010.47.2.112
PMCID: PMC2836445  PMID: 20224709
Aneurysm; Intracranial; Unruptured; National survey; Korea; Multicenter study; Treatment outcome
22.  Combination Treatment for Rapid Growth of a Saccular Aneurysm on the Internal Carotid Artery Dorsal Wall: Case Report 
Aneurysms arising from non-branching sites of the supraclinoid internal carotid artery (ICA) are considered rare, accounting for only 0.9-6.5% of all ICA aneurysms. They are thin-walled, broad-based, can easily rupture during surgery, and are referred to as dorsal, superior, anterior, or ventral wall ICA aneurysms, as well as blister-like aneurysms. Various treatment modalities are available for blister-like aneurysms, but with varying success. Here, we report on two cases of saccular shaped dorsal wall aneurysms. Both patients were transferred to the emergency department with subarachnoid hemorrhage because of an aneurysmal rupture. Computed tomography angiography and transfemoral cerebral angiography (TFCA) showed a dorsal wall aneurysm in the distal ICA. We performed clipping on the wrapping material (Lyodura®, temporal fascia). Follow-up TFCA showed rapid configuration changes of the right distal ICA. Coil embolization was also performed as a booster treatment to prevent aneurysm regrowth. Both patients were discharged without neurologic deficit. No evidence of aneurysm regrowth was observed on follow-up TFCA at two years. Dorsal wall ICA aneurysms can change in size over a short period; therefore, follow-up angiography should be performed within the short-term. In cases of regrowth, coil embolization should be considered as a booster treatment.
doi:10.7461/jcen.2014.16.3.303
PMCID: PMC4205260  PMID: 25340036
Dorsal wall aneurysm; Subarachnoid hemorrhage; Wrapping; Coiling
23.  Sole Stenting Technique for Treatment of Complex Aneurysms 
Objective
Complex aneurysms such as fusiform and very small aneurysms (< 3 mm) are challenging in neurovascular and endovascular surgery. Author reports follow-up results of 9 cases treated by sole stent technique with pertinent literature review.
Methods
A retrospective study was made of 9 patients who were treated by sole stenting technique for cerebral aneurysm between January 2003 and January 2009. Two of them had fusiform aneurysm, 5 had very small aneurysm, and 2 had small saccular aneurysm. Five patients had ruptured aneurysms and four had unruptured aneurysms. Seven aneurysms were located in the internal carotid artery (ICA), 1 in the middle cerebral artery (MCA) and 1 in the basilar artery. Follow-up cerebral angiography was performed at post-procedure 3 months, 6 months, and 12 months. Mean follow-up period is 30 months (ranged from 3 days to 30 months).
Results
Aneurysm size was decreased in 6 of 9 cases on follow-up images and was not changed in 3 cases. Although total occlusion was not seen, patients had stable neurological condition and angiographic result. The procedural complication occurred in 2 cases. One was coil migration and the other was suboptimal deployment of stent, and both were asymptomatic. Re-bleeding and thromboembolic complication had not been occurred.
Conclusion
Sole stenting technique is relatively effective and safe as an alternative treatment for fusiform and very small aneurysms.
doi:10.3340/jkns.2009.46.6.545
PMCID: PMC2803270  PMID: 20062570
Sole stenting technique; Fusiform aneurysm; Very small aneurysm
24.  Result of Neck Clipping and Coil Embolization as a Treatment for Unruptured Aneurysm 
Interventional Neuroradiology  2007;13(Suppl 1):151-156.
Summary
The report of the International Subarachnoid Aneurysm Trial (ISAT) study showed that coil embolization was superior to neck clipping as a treatment for subarachnoid hemorrhage (SAH)1. Recently, some results of treatments for unruptured aneurysm via coil embolization and neck clipping have been reported 2,3. We compared the results of coil embolization and neck clipping in our institute. Generally better outcomes were obtained by endovascular surgery than by neck clipping. Postoperative ischemic strokes occurred in one case (1.8%) as a major stroke and in three cases (5.6%) as a minor stroke among coil-treated cases, and in two cases(2.6%) as a major stroke, and in seven cases(9.0%) as a minor stroke among neck clipping cases.
Other complications after these treatments were six cases of subdural effusion/hematoma, four cases of infection, two cases of epidural hematoma, one abducens nerve palsy, one hydrocephalus, and one acute myocardial infarction among 78 neck clipping cases, and two subcutaneous hematoma, one pseudoaneurysm at the puncture points, one direct carotid-cavernous fistula among 54 coil-treated cases. Four coil-treated cases, in which introduction of microcatheters to the aneurysm was impossible, were treated completely by neck clipping after endovascular treatments. In terms of modified Rankin Scale(mRS) three months after treatments, while mRS 3 was noted in only one case in the endovascular treatment group, there were one case of mRS 3, two cases of mRS 4, and two cases of mRS 5 in the neck clipping group. Duration of hospitalization averaged 11.9 days in the endovascular group and 24.1 days in the neck clipping group. The results of endosaccular enbolizations as treatment of the unruptured aneurysm seems to be better than neck clipping. However, not all cases of unruptured aneurysms can be treated by coil embolization due to the width of aneurysmal neck and relation of the aneurysm to parent arteries. Therefore, surgeons should also be able to perform neck clipping as an alternative modality.
PMCID: PMC3345460  PMID: 20566094
unruptured aneurysm, coil embolization, neck clipping
25.  When Is Posterolateral Orbitotomy Useful in a Pterional Craniotomy? A Morphometric Study 
Skull Base  2011;21(3):147-152.
Adding posterolateral orbitotomy to pterional craniotomy allows greater exposure of the anterolateral skull base. However, there is a paucity of literature quantifying the relative benefit of adding posterolateral orbitotomy for various surgical targets. Our study is a step to address this issue. We performed dissections of five cadaveric heads (10 sides). The anterior communicating artery (A-Com) complex, posterior chiasm (anterior third ventricular region), ipsilateral optic canal, and ipsilateral supraclinoid internal carotid artery (ICA) bifurcation were chosen as targets. A pterional craniotomy was performed and the targets were morphometrically analyzed. Subsequently, posterolateral orbitotomy was done and analysis repeated. The field of view and measurements quantifying the angle of attack were compared. Addition of orbitotomy to pterional craniotomy increased the angle of exposure to ICA bifurcation, anterior third ventricular region, and A-Com complex by average of 15%, 29%, and 50%, respectively. Our study shows the addition of a posterolateral orbitotomy to the pterional craniotomy improves the angle of attack to the anterior third ventricular region and the A-Com complex, thus supporting the use of orbitopterional craniotomy for suprasellar lesions extending into anteroinferior third ventricle and A-Com aneurysms that point superiorly/posteriorly.
doi:10.1055/s-0031-1275242
PMCID: PMC3312105  PMID: 22451817
Pterional craniotomy; posterolateral orbitotomy; Morphometric; study

Results 1-25 (642961)