Radiographic and microsurgical characteristics of proximal (A1) segment aneurysms of the anterior cerebral artery.

BACKGROUND: Proximal A1 segment aneurysms of the anterior cerebral artery (ACA) radiologically resemble internal carotid artery bifurcation (ICBIF) aneurysms because of their anatomical proximity. However, proximal A1 aneurysms exhibit distinguishing features, relative to ICBIF aneurysms. We report our experience of managing proximal A1 aneurysms, then compare them to ICBIF aneurysms. METHODS: Among 2191 aneurysms treated between 2000 and 2016 in a single institution, we retrospectively reviewed 100 cases categorized as ICBIF or A1 aneurysms. We included aneurysms originating from the ICBIF and ACA, proximal to the anterior communicating artery (A1 segment) and divided them into two groups: proximal A1 (n = 32) and ICBIF (n = 50). If any portion of the aneurysm involved the ICBIF, it was classified as ICBIF. Aneurysms wholly located in the A1 segment were classified as proximal A1. Patient factors and angiographic factors were evaluated and compared. RESULTS: The proximal A1 group exhibited differences in aneurysm size (p = 0.013), posterior aneurysm direction (p = 0.001), and A1 perforators as incorporating vessels (p = 0.001). The proximal A1 group tended to rupture more frequently when the aneurysm was smaller (p = 0.046). One case of morbidity occurred in the proximal A1 group. CONCLUSION: Compared to ICBIF aneurysms, proximal A1 aneurysms were smaller and directed posteriorly, with incorporating perforators. Because of these characteristics, it may be difficult to perform clipping with 360° view in microsurgical field. Therefore, when planning to treat proximal A1 aneurysms, different treatment strategies may be necessary, relative to those used for ICBIF aneurysms.

A Protocol-Based Decision for Choosing a Proper Surgical Treatment Option for Carotid Artery Stenosis.

OBJECTIVE: There are two established surgical treatment options for carotid artery stenosis. Carotid endarterectomy (CEA) has been accepted as a gold standard for surgical treatment while carotid artery stenting (CAS) has recently become an alternative option. Each treatment option has advantages and disadvantages for the treatment outcomes. We propose a protocol for selection of a proper surgical treatment option for carotid artery stenosis. MATERIALS AND METHODS: A total of 192 published articles on management of carotid artery stenosis were reviewed. Preoperatively considerable factors which had been repeatedly noted in those articles for the risk/benefits of CEA or CAS were selected. According to those factors, a protocol with four categories was established. RESULTS: CEA or CAS is indicated when the patient has a symptomatic stenosis ≥ 50%, or when the patient has an asymptomatic stenosis ≥ 80%. Each treatment option has absolute indications and favorable indications. Each absolute indication is scored with three points, and each favorable indication, one point. Based on the highest scores, a proper treatment option (CEA or CAS) is selected. CONCLUSION: We have been treating patients according to this protocol and evaluating the outcomes of our protocol-based decision because this protocol might be helpful in assessment of risk/benefit for selection of a proper surgical treatment option in patients with carotid artery stenosis.

Clinical Risk Factors Affecting Procedure-Related Major Neurological Complications in Unruptured Intracranial Aneurysms.

PURPOSE: The operative risk and natural history rupture risk for the treatment of unruptured intracranial aneurysms (UIAs) should be evaluated. The purpose of this study was to report our experience with treating UIAs and to outline clinical risk factors associated with procedure-related major neurological complications. MATERIALS AND METHODS: We treated 1158 UIAs in 998 patients over the last 14 years. All patients underwent operation performed by a single microvascular surgeon and two interventionists at a single institution. Patient factors, aneurysm factors, and clinical outcomes were analyzed in relation to procedure-related complications. RESULTS: The total complication rate was 22 (2.2%) out of 998 patients. Among them, complications developed in 14 (2.3%) out of 612 patients who underwent microsurgery and in 8 (2.1%) out of 386 patients who underwent endovascular procedures. One patient died due to intraoperative rupture during an endovascular procedure. The procedure-related complication was highly correlated with age (p=0.004), hypertension (p=0.002), and history of ischemic stroke (p<0.001) in univariate analysis. The multivariate analysis revealed previous history of ischemic stroke (p=0.001) to be strongly correlated with procedure-related complications. CONCLUSION: A history of ischemic stroke was strongly correlated with procedure-related major neurological complications when treating UIAs. Accordingly, patients with UIAs who have a previous history of ischemic stroke might be at risk of procedure-related major neurological complications.

Clinico-radiological Characteristics of Spontaneous Basal Ganglia Hemorrhage, According to Regional Classification.

OBJECTIVE: The clinico-radiologic features of the spontaneous basal ganglia hemorrhage (BGH) may often differ one from another, according to its regional location. Therefore, we attempted to classify the BGH into regional subgroups, and to extrapolate the distinct characteristics of each group of BGH. MATERIALS AND METHODS: A total of 103 BGHs were analyzed by retrospective review of medical records. BGH was classified according to four subgroups; anterior BGH; posterior BGH; lateral BGH; massive BGH. RESULTS: The most common BGH was the posterior BGH (56, 54.4%), followed by the lateral BGH (26, 25.2%), the massive BGH (12, 11.7%), and the anterior BGH (9, 8.7%). The shape of hemorrhage tended to be round in anterior, irregular in posterior, and ovoid in lateral BGH. A layered density of hematoma on initial computed tomography showed correlation with hematoma expansion (p = 0.016), which was observed more often in the postero-lateral group of BGH than in the anterior BGH group. Relatively better recovery from the initial insult was observed in the lateral BGH group than in the other regional BGH groups. The proportion of poor outcome (modified Rankin scale 4, 5, 6) was 100% in the massive, 41.1% in the posterior, 34.6% in the lateral, and 0% in the anterior BGH group. CONCLUSION: We observed that BGH can be grouped according to its regional location and each group may have distinct characteristics. Thus, a more sophisticated clinical strategy tailored to each group of BGHs can be implemented.

Benefits of surgical treatment for unruptured intracranial aneurysms in elderly patients.

OBJECTIVE: Due to longer life spans, patients newly diagnosed with unruptured intracranial aneurysms (UIAs) are increasing in number. This study aimed to evaluate how management of UIAs in patients age 65 years and older affects the clinical outcomes and post-procedural morbidity rates in these patients. METHODS: We retrospectively reviewed 109 patients harboring 136 aneurysms across 12 years, between 1997 and 2009, at our institute. We obtained the following data from all patients : age, sex, location and size of the aneurysm(s), presence of symptoms, risk factors for stroke, treatment modality, and postoperative 1-year morbidity and mortality. We classified these patients into three groups : Group A (surgical clipping), Group B (coil embolization), and Group C (observation only). RESULTS: Among the 109 patients, 56 (51.4%) underwent clipping treatment, 25 (23%) patients were treated with coiling, and 28 observation only. The overall morbidity and mortality rates were 2.46% and 0%, respectively. The morbidity rate was 1.78% for clipping and 4% for coiling. Factors such as hypertension, diabetes mellitus, hypercholesterolemia, smoking, and family history of stroke were correlated with unfavorable outcomes. Two in the observation group refused follow-up and died of intracranial ruptured aneurysms. The observation group had a 7% mortality rate. CONCLUSION: Our results show acceptable favorable outcome of treatment-related morbidity comparing with the natural history of unruptured cerebral aneurysm. Surgical clipping did not lead to inferior outcomes in our study, although coil embolization is generally more popular for treating elderly patients. In the treatment of patients more than 65 years old, age is not the limiting factor.