Vascularization of the uncus - Anatomical study and clinical implications.

BACKGROUND: The objective of this paper was to describe the arterial supply of the uncus and quantify the branches directed to the anteromedial aspect of the human temporal cortex. METHODS: We studied 150 human cerebral hemispheres identifying main afferent arteries supplying the anteromedial temporal cortex with particular attention to the uncus, determining the territory supplied by each artery through either cortical or perforating branches. RESULTS: The uncus was supplied by 419 branches of the anterior choroidal artery (AChA), 210 branches of the internal carotid artery (ICA), 353 branches of the middle cerebral artery (MCA), and 122 branches of the posterior cerebral artery (PCA). The total of supplying vessels was 1104 among the 150 hemispheres studied, which corresponds to 7.36 arteries per uncus. The average of branches per hemisphere was as follows: 2.79 from AChA, 1.40 from ICA, 2.35 from MCA, and 0.81 from PCA. The relative contribution of each artery for the total of specimens studied was as follows: 38% from AChA, 19% from ICA, 32% from the MCA, and 11% from the PCA. We identified cortical anastomoses mostly between the MCA and PCA (27 cases). CONCLUSION: We described and quantified the uncus' vascularization, including anatomical variations. This updated, detailed description of the mesial temporal vascularization is paramount to improve the treatment of neurosurgical conditions.

Routine postoperative computed tomography scan after craniotomy: systematic review and evidence-based recommendations.

Over the last few years, the role of early postoperative computed tomography (EPOCT) after cranial surgery has been repeatedly questioned, but there is yet no consensus on the practice. We conducted a systematic review to address the usefulness of EPOCT in association with neurological examination after elective craniotomies compared to the neurological examination alone. Studies were eligible if they provided information about the number of patients scanned, how many were asymptomatic or presented neurological deterioration before the scan and how many of each of those groups had their management changed due to imaging findings. CTs had to be performed in the first 48 h following surgery to be considered early. Eight studies were included. The retrospective studies enrolled a total of 3639 patients, with 3737 imaging examinations. Out of the 3696 CT scans performed in asymptomatic patients, less than 0.8% prompted an intervention, while 100% of patients with neurological deterioration were submitted to emergency surgery. Positive predictive values of altered scans were 0.584 for symptomatic patients and 0.125 for the asymptomatic. The number of altered scans necessary to predict (NNP) one change in management for the asymptomatic patients was 8, while for the clinically evident cases, it was 1.71. The number of scans needed to diagnose one clinically silent alteration is 134.75, and postoperative imaging of neurologically intact patients is 132 times less likely to issue an emergency intervention than an altered neurological examination alone. EPOCT following elective craniotomy in neurologically preserved patients is not supported by current evidence, and CT scanning should be performed only in particular conditions. The authors have developed an algorithm to help the judgment of each patient by the surgeon in a resource-limited context.

Comparison of surgical and endovascular treatments for fusiform intracranial aneurysms: systematic review and individual patient data meta-analysis.

Fusiform intracranial aneurysms (FIA) are associated with significant morbidity and mortality. We carried out a systematic review and meta-analysis of individual participant data with propensity score adjustment to compare the functional and angiographic outcomes between surgical and endovascular approaches to FIA. We conducted a systematic review for articles on the treatment of FIA with individual patient-level detailing. Data from patients treated for FIA in our institution from 2010 to 2018 were also collected. The primary studied outcome was morbidity, and secondary outcomes were angiographic results and retreatment. Propensity score-adjusted mixed-effects logistic regression models evaluated treatment options, stratified by anatomical location. Compiling original and published data, there were 312 cases, of which 79 (25.3%) had open surgery, and 233 (74.5%) were treated with endovascular procedures. There were no differences between treatment groups, for neither cavernous ICA (OR 1.04, 95% CI 0.05-23.6) nor supraclinoid aneurysms (OR 7.82, 95% CI 0.65-94.4). Both size (OR 1.11, 95% CI 1.03-1.19) and initial mRS (OR 2.0, 95% CI 1.2-3.3) were risk factors for morbidity, independent of location. Neither age nor rupture status influenced the odds of posterior morbidity. Unfavorable angiographic outcomes were more common in the endovascular group for supraclinoid and vertebrobasilar aneurysms (χ2, P < 0.01). There were no differences between morbidity of surgical and endovascular treatments for FIA, regardless of aneurysm location. Size and initial mRS were correlated with functional outcomes, whereas age and rupture status were not. Microsurgery seems to yield better long-term angiographic results compared to endovascular procedures.

Multiple and mirror intracranial aneurysms: study of prevalence and associated risk factors.

OBJECTIVE: Multiple intracranial aneurysms (MIA) account for 30% of all intracranial aneurysms, while mirror aneurysms, a subgroup of MIA, are present in 5% of all patients with cerebral aneurysms. We investigated the risk factors associated with the presence of multiple and mirror intracranial aneurysms. METHODS: 1404 patients, 314 males (22.4%) and 1090 female (77.6%) were enrolled for this study. Diagnosis was performed with a digital subtraction angiography (DSA). Multiplicity was defined as the presence of two or more aneurysms and mirror aneurysms as one pair of aneurysms involving bilateral corresponding arteries. Patients were followed-up from September 2009 till August 2018. Individuals' characteristics such as sex, age, smoking, hypertension and use of contraceptives were evaluated. RESULTS: Five hundred and twelve patients (36.4%) were diagnosed with MIA, approximately 4%/year. We observed 203 pairs of mirror aneurysms, accounting for 406 aneurysms (13% of the population). There was an increased frequency of females with multiple (p < 0.001, OR = 1.883, 95% CI = 1.386-2.560) and mirror aneurysms (p < 0.001, OR = 2.828, 95% CI = 1.725-4.636). Smoking was associated with multiplicity (p< 0.001, OR = 1.458, 95% CI = 1.160-1.833), as well as advanced age (p < 0.001, OR = 1.938, 95% CI = 1.438-2.611), but there was no significant relation with presence of mirror aneurysms. We observed higher frequency of baby aneurysms (<3mm) in the group of patients with MIA, while giant aneurysms (>25 mm) were most found in patients with only one aneurysm (p < 0.001). No differences between patients who used contraceptives against patients who did not use were found (p = 0.600). CONCLUSIONS: Gender and smoking, known risk factors to the development of a single intracranial aneurysm, are proportionally increased in patients with MIA. Hypertension and oral contraceptives were not associated with multiplicity.

Cavernous carotid aneurysms do not influence the occurrence of upstream ipsilateral aneurysm.

OBJECTIVE: Cavernous carotid aneurysms (CCA) comprehend around 5% of all intracranial aneurysms. The main risk factors for an intracranial aneurysm seem not to influence the incidence of CCAs. The aim of this study was to investigate the association of CCAs and the presence of upstream aneurysms. METHODS: 1403 patients, admitted in Hospital das Clinicas de São Paulo, Brazil, from September 2009 to August 2018, enrolled this study. Diagnosis was performed with Digital Subtraction Angiography (DSA). Upstream aneurysm was defined as an intracranial aneurysm on anterior cerebral circulation, ipsilateral to the CCA (if present) or crossing the midline (e.g. anterior communicating artery). RESULTS: 177 individuals were diagnosed with CCA (12.6% of the population), totalizing 225 aneurysms (10% of the total number of aneurysms, 2253). No association was found between CCA and UA (p= .090, OR: 1.323, 95% CI: 0.957-1.828). Studying only patients with CCA, multivariable analysis showed smoking as the only factor associated with UA (p= .010, OR: 0.436, 95% CI: 0.232-0.821). CONCLUSIONS: Cavernous carotid aneurysms were present in 12% of our population, mostly in female. They seem to be independent of the modifiable risk factors already associated with intracranial aneurysms. A higher frequency of mirror aneurysms was seen in this location. CCA did not influence the presence of ipsilateral and anterior circulation aneurysms.

The current clinical picture of cerebral proliferative angiopathy: systematic review.

BACKGROUND: Cerebral proliferative angiopathy (CPA) is a rare subset of arteriovenous malformations (AVM). It has unique clinical presentation, angiographic characteristics, and pathophysiology which often brings challenges for the treatment. We aimed to define its epidemiology, pathophysiology are unknown, and best management strategies. METHODS: A systematic review was conducted according to the PRISMA guidelines. MEDLINE was searched for articles regarding CPA. Extracted data included epidemiological, clinical, and angiographical characteristics, treatment, and outcomes. Treatment was classified as conservative, radiosurgery, endovascular, decompression, and indirect vascularization. A meta-analytical approach was employed for description of the data as study-size adjusted percentages or weighted means, as appropriate. RESULTS: Thirty-three studies were analyzed, rendering a total 95 cases-half of which came from a single study. Patients were predominantly young (mean 23 years old) and female (60.0%) presenting with headaches (44.9%), seizures (37.1%), or transient ischemic attacks (33.7%). Hemorrhage was present in 18.0%, but rebleeding rates were as high as 67%. The majority of nidus were > 6 cm (52.5%) with hemispheric extension (73.0%). Capillary angioectatic appearance (85.7%), transdural supply (62.5%), and deep venous drainage (73.0%) were also frequent features. Most patients were treated conservatively (54.4%), followed by endovascular (34.2%). Indirect vascularization and radiosurgery were attempted in five and two patients, respectively. Mean follow-up was 110.8 patient-years. Neurological status improved in 50.7%, remained stable in 40.2%, and worsened in 9.0%. CONCLUSIONS: Conservative and endovascular treatments seem adequate interventions, despite limited evidence. Complementary techniques can be used in patients throughout disease history, according to symptom-based, individualized approach. More studies are required for choosing interventions based on reliable long-term results.

Papillary Tumor of the Pineal Region: Systematic Review and Analysis of Prognostic Factors.

BACKGROUND: Clinical outcomes and biological behavior of papillary tumors of the pineal region (PTPR) are still under investigation. The best therapeutic strategy has not been defined. OBJECTIVE: To perform a comprehensive patient-level analysis of all PTPR cases and identify their clinical features, treatment options, and prognostic factors. METHODS: A search of the medical databases for case series and reports on PTPRs from January 2003 to June 2017 was performed. Data addressing PTPR's clinical presentation, imaging, treatment, and histological features were. Variables associated with the primary outcome of 36-mo survival were identified through Cox regression models. RESULTS: The initial search yielded 1164 studies, of which 71 were included (60 case reports and 11 case series), containing 177 patients (mean age 33.0 ± 15.3 yr and 53.2% male). Intracranial hypertension and hydrocephalus prevailed as the clinical picture. Surgery was performed on 82.0% and gross total resection (GTR) was achieved on 71.4%. A total of 56.8% recurred after a median 29 mo (quartiles 10.5-45.5). The 36-mo survival rate was 83.5% (95% confidence interval [CI] 76.2-89.2%). Good functional outcomes (Glasgow Outcome Scale 4/5) were observed in 60.0%. The variables of interest were inconsistently reported and the multivariable analysis final sample was 133 patients. After adjustment for age, tumor size (each additional centimeter, hazard ratio [HR] 1.99, 95% CI 1.12-3.53, P = .019) and surgical treatment (HR 0.16, 95% CI 0.05-0.45, P = .001) were associated with 36-mo survival. CONCLUSION: Tumor size and surgery are associated with improvement in 36-mo survival. We did not observe any significant benefits from GTR or adjuvant treatments.

Epidemiological analysis of 1404 patients with intracranial aneurysm followed in a single Brazilian institution.

BACKGROUND: We sought to evaluate the epidemiology of intracranial aneurysms in relation to location, gender, age, presence of multiple aneurysms, and comorbidities in the Brazilian population. METHODS: We performed a prospective analysis of a cohort of 1404 patients diagnosed with intracranial aneurysm admitted to the Hospital das Clinicas of the University of Sao Paulo, a referral hospital for the treatment of cerebrovascular diseases in Brazil. Patients admitted between September 2009 and September 2018 with radiological diagnosis of intracranial aneurysm were included in the study. RESULTS: A total of 2251 aneurysms were diagnosed. Females accounted for 1090 aneurysms (77.6%) and the mean age at diagnosis was 54.9 years (ranging 15-88). The most common location was middle cerebral artery (MCA) with 593 aneurysms (26.3%) followed by anterior cerebral artery (ACA) with 417 aneurysms (18.5%) and internal carotid artery in the posterior communicating segment with 405 aneurysms (18.0%). Males had higher rates of ACA aneurysms (29.7%) while females had higher rates of MCA aneurysms (26.1%). Sorting by size, 492 aneurysms were <5 mm (21.8%), 1524 measured 5-10 mm (67.7%), 119 size 11-24 mm (5.3%), and 116 were >24 mm (5.2%). The occurrence of multiple aneurysms was associated with female gender (P < 0.001) and smoking (P < 0.001), but not with hypertension (P = 0.121). CONCLUSION: In this population, the occurrence of intracranial aneurysm is related to several factors, including gender, age, smoking, and hypertension. Our study brought to light important characteristics of a large number of Brazilian patients regarding epidemiology, location, size, and multiplicity of intracranial aneurysms.

Pterional, Pretemporal, and Orbitozygomatic Approaches: Anatomic and Comparative Study.

OBJECTIVE: Although pterional craniotomy and its variants are the most used approaches in neurosurgery, few studies have evaluated their precise indications. We evaluate the pterional (PT), pretemporal (PreT), and orbitozygomatic (OZ) approaches through quantitative measurements of area, linear, and angular exposures of the major intracranial vascular structures. METHODS: Eight fresh, adult cadavers were operated with the PT, followed by the PreT, and ending with the OZ approach. The working area, angular exposure of vascular structures and linear exposure of the basilar artery were measured. RESULTS: The OZ approach presented a wider area (1301.3 ± 215.9 mm2) with an increase of 456.7 mm2 compared with the PT and of 167.4 mm2 to the PreT (P = 0.011). The extension from PT to PreT and OZ increases linear exposure of the basilar artery. When comparing the PreT and OZ, we found an increase in the horizontal and vertical angle to the bifurcation of the ipsilateral middle cerebral artery (P = 0.005 and P = 0.032, respectively), horizontal angle to the basilar artery tip (P = 0.02), and horizontal angle to the contralateral ICA bifurcation (P = 0.048). CONCLUSIONS: The OZ approach offered notable surgical advantages compared with the traditional PT and PreT regarding to the area of exposure and linear exposure to basilar artery. Regarding angle of attack, the orbital rim and zygomatic arch removal provided quantitatively wider exposure and increased surgical freedom. A detailed anatomic study for each patient and surgeon experience must be considered for individualized surgical approach indication.