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.
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.
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.
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.
Cerebral aneurysm; Craniotomy; Minimally invasive; Mini-pterional; Supraorbital; Surgical exposure
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.
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.
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.
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.
Extradural anterior clinoidectomy; Paraclinoid aneurysm; Clinical outcomes; Surgical complications
A fenestration of the supraclinoid internal carotid artery (ICA) is a rare congenital condition. We report an aneurysm arising from the proximal end of an ICA fenestration that was treated by endovascular coiling. Three-dimensional rotational angiography of preoperative cerebral angiography provided an understanding of the complex anatomy of the aneurysms associated with the fenestration and may facilitate the clinical decision regarding the treatment option. Endovascular coiling appears to be safe and effective for treating an aneurysm originating from a fenestration on the supraclinoid ICA, which is a difficult lesion to treat using a conventional surgical approach.
Internal carotid artery; Fenestration; Aneurysm; Coil embolization; Angiography
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.
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.
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).
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.
Anterior choroidal artery infarction; Clip; Intracranial aneurysm
The purpose of this study was to determine the outcomes of surgical clipping in patients with unruptured middle cerebral artery (MCA) aneurysms.
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.
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.
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.
Aneurysm; Middle cerebral artery; Surgical clip; Treatment outcome
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.
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.
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.
The lateral supraorbital approach for the clipping of unruptured intracranial aneurysm could be a good alternative to the classic pterional approach.
Supraorbital approach; Pterional approach; Aneurysm; Clipping
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.
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.
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.
The supraorbital keyhole approach reduced intra- and postoperative complications, including chewing discomfort and cosmetic disturbances, compared with the conventional pterional approach.
Pterional approach; Supraorbital approach; Aneurysm; Clipping; Cosmetic outcome
Abnormal contrast enhancement on brain computed tomography (CT) scan after diagnostic or interventional angiography is not rare, and has known to be induced by temporary blood-brain barrier (BBB) disruption from contrast media. Furthermore, it has been regarded as clinically subtle, but reported to have no symptom or mild transient symptoms. However, we recently experienced two cases of serious BBB disruption during the acute period after coiling of an unruptured intracranial aneurysm. One patient presented with an unruptured paraclinoid internal carotid artery (ICA) aneurysm on the right and the other with an unruptured right supraclinoid ICA aneurysm. Both patients showed similar findings on immediate postembolization CT scan and clinical courses after coiling. Typical radiological, clinical characteristics of BBB disruption were described. In addition, the role of immediate postembolization CT scan are also discussed.
Aneurysm; Blood-brain barrier; Coil; Embolization
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.
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).
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.
Surgical clipping of unruptured intracranial aneurysms in elderly group could get it as a favorable outcome in well selected cases.
Unruptured intracranial aneurysm; Surgical clipping; Elderly; Outcome
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.
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.
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.
Internal carotid artery; morphometry; cerebral aneurysm
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.
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).
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.
Sole stenting technique is relatively effective and safe as an alternative treatment for fusiform and very small aneurysms.
Sole stenting technique; Fusiform aneurysm; Very small aneurysm
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.
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
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.
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.
Aneurysm; Clip; Coil; Bypass
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.
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.
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.
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.
Internal carotid artery; Intracranial aneurysm; Giant cerebral aneurysm; Outcome; Quality of life
To compare the preoperative and postoperative health‐related quality of life (QOL) and psychological state of patients with asymptomatic unruptured intracranial aneurysms (ICAs) who underwent elective surgery.
Out of 67 patients who underwent neck clipping of ICAs, we assessed the QOL of 61 patients using Short Form‐36 (SF‐36); their psychological state was rated on the Hospital Anxiety and Depression Scale (HADS) before, 3 months, and 1 and 3 years after treatment.
The preoperative mean scores for each of the eight SF‐36 domains except bodily pain were significantly lower in the study population than in the reference population. 14 (20.9%) patients experienced surgical complications defined as neurological deterioration and/or abnormal CT findings within 30 days of the operation. Despite some complications, the QOL of all operated patients returned to the mean level of the reference population 3 years after treatment. At 3 months after surgery, the scores for psychosocial activities and general health perception were transiently below the preoperative levels. According to the HADS, the patients experienced mild anxiety before the operation; it disappeared by the third postoperative month.
Preoperatively, patients with unruptured ICAs reported a significantly decreased QOL. It further declined transiently after elective surgery, but it returned to the mean level recorded for the reference population within 3 years. Our findings suggest that these patients derived significant QOL benefits from their surgery. Hence subjective QOL issues should be considered in deciding whether treatment‐related risks and their natural history, such as their potential rupture, warrant surgery of asymptomatic unruptured ICAs.
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.
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.
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.
Revascularization technique is a pivotal armament in managing complex aneurysms and scrupulous prior planning is essential to successful outcomes.
Cerebral aneurysm; Extracranial-intracranial bypass; Outcomes
We report 7 patients with symptomatic giant aneurysms in the cavernous portion of the internal carotid artery (ICA) who were treated by trapping the ICA on either side of the aneurysmal orifice using detachable coils. In all 7 patients the ICA was sacrificed; 5 patients subsequently underwent bypass surgery (STA-MCA bypass, n = 4; high-flow bypass, n = 1), the other 2 patients did not. In 6 patients, there were no post-treatment embolic episodes; one patient who had been treated by proximal occlusion of the ICA developed transient ischemia due to an intra-aneurysmal thrombus. Cranial nerve palsies were markedly improved in all patients.
ICA trapping using detachable coils was a highly successful treatment method in these patients. We found the detachable coils effective and easy to use in the trapping methods applied in this series of 7 patients.
cavernous portion, embolism, giant aneurysm, interventional neurosurgery
Background and Objectives
Abdominal Aortic Aneurysm (AAA) and carotid disease have medical and social significance, considering their morbidity, disability, and economic consequences. The study objectives were to determine the prevalence of asymptomatic internal carotid artery (ICA) lesions ≥70% in patients with AAA, the correlation of AAA diameter with the degree of ICA stenosis and symptoms, and the importance of preventive ultrasound checkups.
Subjects and Methods
A prospective non-randomized controlled study including 740 patients, aged from 18-85 years, who were suitable for the inclusion and exclusion criteria and reported at the vascular laboratory of the Institute for Vascular and Endovascular Surgery, Clinical Center of Serbia from 1st of December 2011 to the 1st of November 2012.
The prevalence of asymptomatic ICA stenosis ≥70% in patients with AAA is 10.8%. Male representatives have more symptomatic ICA stenosis ≥70%. Patients with small aneurysms more often have asymptomatic ICA stenosis ≥70%. The occurrence of symptoms of carotid disease was more prevalent among patients with ICA stenosis ≥70% compared to the group with stenosis <70%. There was no correlation found between the grade of ICA stenosis with the size of AAA.
The prevalence of asymptomatic ICA stenosis ≥70% in patients with AAA is found to be 10.8%. Male patients with ICA stenosis ≥70% more often had symptoms of carotid disease. In the smaller aneurysms, ICA stenosis ≥70% occurs frequently, but without the symptoms of carotid disease, and there was no correlation between the size of AAA and the grade of ICA stenosis. Clinical implications of ICA imaging in patients with previously diagnosed AAA is necessary.
Prevalence; Signs and Symptoms; Internal carotid artery stenosis; Aortic aneurysm, abdominal
Several de novo intracranial aneurysms have been described related to changes in hemodynamics after therapeutic occlusion of internal carotid artery (ICA); however, de novo aneurysms related to a supraclinoid arteriosclerotic stenosis of the ICA have not been described yet. Authors consider that it is important to bear in mind the possibility of developing an aneurysm in these special conditions.
The evolution of a 62-year-old patient with subarachnoid hemorrhage, intraparenchymal frontal hematoma with some atypical circumstances that were presented together as well as the treatment he received are shown in this report. We can see this patient suffered a right thalamic hemorrhage at the age of 51 years; this condition was associated to a severe atherosclerotic stenosis of right supraclinoid ICAy. A long term had elapsed since the diagnosis of the stenosis and the discovery of a ruptured ipsilateral de novo supraclinoid internal carotid artery-posterior communicating artery (ICA-PcomA) aneurysm.
It seems like both conditions: the atherosclerotic supraclinoid ICA which tells of an Samano et at: Ruptured De Novo PcomA Aneurysm Associated with Arteriosclerotic Stenosis of Supraclinoid ICA. Altered vessel environment coupled to a long exposure time, hemodynamic changes, unbalance in the wall sheer stress could all of them lead to the development of the de novo aneurysm.
Aneurysm; atherosclerosis; de novo; intracranial carotid artery; stenosis; subarachnoid hemorrhage
The International Study of Unruptured Intracranial Aneurysms (ISUIA) reported that the 5-year cumulative rupture rate of small unruptured aneurysms less than 7 mm in diameter is very low depending on the aneurysm's location. However, we have seen a large number of ruptured aneurysms less than 7 mm in clinical practice. The purpose of this study was to review our experience and to measure the size and location at which aneurysms ruptured in our patient population.
We reviewed the characteristics of aneurysms, such as size and location, from the original angiograms of patients who were admitted to our hospital between January 2004 and December 2007. All aneurysms were treated surgically or through endovascular procedures.
Interventional or surgical treatment was given to a total of 889 patients, including 568 females and 321 males. At the time of our study, 627 cases were ruptured aneurysms and 262 cases were unruptured aneurysms. Of the ruptured cases, the mean diameter of the aneurysm was 6.28 mm. We found that 71.8% of ruptured aneurysms were smaller than 7 mm in diameter, and 87.9%, were smaller than 10 mm. Based on location, the data show that anterior communicating artery aneurysms most often presented with rupture sizes less than 7 mm (76.8%) and 10 mm (92.1%) in diameter. Most ruptured aneurysms were less than 7 mm in size, although recent studies have noted that small aneurysms are less likely to rupture.
Although the natural history of unruptured intracranial aneurysms remains controversial, the aneurysm size and location play a signigicant role in determining the risk of rupture. Larger sample sizes and a long term study are needed to reveal the natural history and the rupture risk of unruptured intracranial aneurysms because the size of most ruptured aneurysms was less than 7 mm in diameter in our series.
Size; Location; Age; Intracranial aneurysm; Rupture
To review the current knowledge of screening and treatment of asymptomatic unruptured intracranial aneurysms (AUIAs) using a case-based approach.
SOURCES OF INFORMATION
PubMed was searched from January 1995 to January 2008 using the phrase unruptured intracranial aneurysm. Scientific statements of the Stroke Council of the American Heart Association pertaining to intracranial aneurysms were also reviewed.
Most small AUIAs (≤ 5 mm) do not rupture, and the risks of treatment are substantial. Most small AUIAs can therefore be managed conservatively. Endovascular coiling or surgical clipping of larger aneurysms (> 5 mm) should be considered on a case-by-case basis.
There is currently a lack of sound scientific evidence to support treatment of unruptured intracranial aneurysms. A prospective randomized controlled trial—Trial on Endovascular Aneurysm Management—is now under way to address this issue. It is expected to conclude in 2021.
The present paper is concerned with the 55 aneurysms out of a total of 158 that caused isolated paralysis of the oculomotor nerve. The majority arose from the internal carotid artery after it had pierced the dura (supraclinoid). Rarely the aneurysm sprang from the basilar artery. In two-thirds of the cases there had been a subarachnoid hæmorrhage from leakage. Not more than 10% of patients had arteriosclerosis. Calcification of the sac is not a sign that the aneurysm has thrombosed. The only certain way of demonstrating the position and size of an intracranial aneurysm is by arteriography, which is a safe procedure.
The correct treatment is by carotid ligature. In about 8% of normals the circle of Willis is incomplete, therefore percutaneous compression must first be tried. The only fatalities from ligature were in persons in the acute stage of subarachnoid hæmorrhage, not from meningeal bleeding alone. In this type of case a clip applied to the neck of the sac is probably a better method. In the more usual cases where the hæmorrhage has been spontaneously arrested common carotid ligature in the neck is probably a little safer than intracranial clipping.
Endovascular packing of intracranial aneurysm with preservation of the parent vessel has become in many cases a valid alternative to surgical clipping. Regression of oculomotor disorders after clipping of internal carotid-posterior communicating artery (ICA-PCoA) aneurysms has been well assessed. This report focuses on the reversal of third nerve palsy after endovascular packing of ICA-PCoA aneurysms. To this end, clinical appearances, neuroradiological features, and endovascular interventional procedures of six treated patient are reported and discussed in the light of the very few previous case observations found in the literature. Results indicate that endovascular packing of ICA-PCoA aneurysms may produce effective recovery of correlated third nerve dysfunction.
internal carotid-posterior communicating artery aneurysm, third nerve palsy, endovascular packing, Guglielmi detachable coils
Cerebral aneurysms in Behçet's disease are very rare. The
role of vasculitis in the aetiology of these aneurysms has not been clarified. A 57 year old man with Behçet's disease is described, who
had a subarachnoid hemorrhage due to rupture of a peripheral middle
cerebral artery aneurysm. He underwent a successful aneurysmal clipping. Three years later he had seizures and was found to have a new
aneurysm on the contralateral peripheral middle cerebral artery as well
as some radiological features of vasculitis. After 3 months of steroid
therapy, the aneurysm disappeared. Although surgical treatment is the
first choice for ruptured aneurysms, steroid therapy may be effective
for unruptured small aneurysms in patients with Behçet's disease.
Unruptured non-traumatic dissecting aneurysm in the M4 segment of the middle cerebral artery (MCA) accompanied by complete occlusion of the ipsilateral internal cerebral artery (ICA) has never been reported. A 41-year-old man presented with an infarction manifesting as left-sided weakness and dysarthria. Magnetic resonance angiography revealed a subacute stage infarction in the right MCA territory and complete occlusion of the right ICA. Angiography demonstrated aneurysmal dilatation of the M4 segment of the right MCA. Surgery was performed to prevent hemorrhage from the aneurysm. The aneurysm was proximally clipped guided by Navigation-CT angiography and flow to the distal MCA was restored by superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis. We report this rare case with literature review.
Middle cerebral artery aneurysm; Navigation; Dissecting aneurysm
We report herein a case of a radiation-induced aneurysm. A 69-year-old woman presented with subarachnoid hemorrhage. Eight years previously, she had undergone cranial radiation therapy (total dose of 59.4 Gy) as adjuvant therapy after surgical resection for a chondrosarcoma that was destroying her sphenoid sinus. The patient underwent catheter angiography, which revealed an aneurysm of the anterior communicating artery and luminal narrowing and irregularity in the petrous and lacerum segments of the right internal carotid artery. We attempted surgical clipping of the aneurysm, but there was repeated bleeding. Finally the aneurysm was treated with endovascular trapping. Potentially fatal bleeding also occurred from her internal carotid artery, which had also been irradiated during the previous cranial radiation therapy. We stopped the bleeding with endovascular coil embolization. Because of diffuse vascular changes of the cerebral vessels within irradiated fields, special attention must be paid to their treatment.
Intracranial aneurysm; Subarachnoid hemorrhage; Radiotherapy