Prevalence of unruptured cerebral aneurysms in Chinese adults aged 35 to 75 years: a cross-sectional study.

BACKGROUND: The reported prevalence of unruptured cerebral aneurysms (UCAs) varies widely. OBJECTIVE: To measure the prevalence of UCAs by using 3-dimensional time-of-flight magnetic resonance angiography in adults aged 35 to 75 years. DESIGN: Cross-sectional study done between June 2007 and June 2011. SETTING: Two communities chosen at random from 2 districts (1 urban and 1 suburban) in Shanghai, China. PARTICIPANTS: 4813 adults aged 35 to 75 years. MEASUREMENTS: Three-dimensional time-of-flight magnetic resonance angiography, interpreted by 3 observers blinded to the participants' information, was used to identify the location and size of UCAs and to estimate the overall, age-specific, and sex-specific prevalence. RESULTS: 369 UCAs were found in 336 participants (130 men and 206 women); 4477 participants had no evidence of UCAs. The prevalence was 7.0% overall (95% CI, 6.3% to 7.7%), with 5.5% for men (CI, 4.6% to 6.4%) and 8.4% for women (CI, 7.3% to 9.5%). The overall prevalence of UCAs was higher in women than in men (P < 0.001) and peaked at ages 55 to 64 years in men and women. The UCAs were mostly located in the internal carotid artery (81%), and 90.2% had a maximum diameter less than 5 mm. Mean diameter was larger in women than in men (3.7 mm vs. 3.2 mm; P < 0.009). LIMITATION: Participants were from 2 communities selected from 2 districts in Shanghai, and adults older than 75 years were not studied. CONCLUSION: The overall prevalence of UCAs was 7.0% in Chinese adults aged 35 to 75 years, and most lesions had a diameter less than 5 mm. PRIMARY FUNDING SOURCE: National Natural Science Foundation of China.

Large-cohort comparison between three-dimensional time-of-flight magnetic resonance and rotational digital subtraction angiographies in intracranial aneurysm detection.

BACKGROUND AND PURPOSE: The value of MR angiography varies in diagnosis of intracranial aneurysms due to the difference of equipment and imaging technique. This study was to compare the effectiveness of 3-dimensional time-of-flight MR angiography at 3 T and rotational digital subtraction angiography, both with volume rendering (VR), in detecting intracranial aneurysms. METHODS: One hundred thirty-eight patients with suspected or known aneurysms and other cerebral vascular diseases detected by MR angiography underwent digital subtraction angiography examinations. Postprocessing techniques, including VR and the single artery highlighting method, were performed by a 3-dimensional specialist. The VR-digital subtraction angiography was obtained as the gold standard. RESULTS: The rotational digital subtraction angiography and VR-digital subtraction angiography revealed 146 aneurysms in 122 patients and no aneurysms in 16 patients. Of the 276 vessels examined, 136 vessels had 146 aneurysms and 140 vessels had none. Per vessel and per aneurysm sensitivities were 100%, whereas the per vessel accuracy ranged from 97.5% to 98.6% and the per aneurysm accuracy ranged from 95.1% to 97.0%. CONCLUSIONS: VR 3-dimensional time-of-flight MR angiography at 3 T has excellent sensitivity, accuracy, and correlation with VR-digital subtraction angiography and is comparable to catheter cerebral angiography for the evaluation of patients with intracranial aneurysms who tolerate MR angiography well.

Incidental findings of persistent primitive trigeminal artery on 3-dimensional time-of-flight magnetic resonance angiography at 3.0 T: an analysis of 25 cases.

BACKGROUND AND PURPOSE: Currently, the presence of persistent primitive trigeminal artery (PPTA) is detected by digital subtraction angiography (DSA); most publications on this cerebrovascular variation have been individual case reports. This study is to evaluate the efficacy of 3-dimensional time-of-flight magnetic resonance angiography (3D-TOF MRA) at 3.0 T for the detection and classification of PPTA based on a large case series. MATERIALS AND METHODS: Between June 2007 and October 2008, 4,650 patients underwent magnetic resonance angiography (MRA) examination at 3.0 T in our hospital. MRA was performed using 3D-TOF with volume rendering (VR) and maximum intensity projection (MIP) technique. The PPTA was classified according to the Saltzman classification system. The occurrence of cerebral vascular diseases accompanying PPTA was studied. RESULTS: Among the 4,650 patients with MRA examined, 25 were identified as having PPTA; the prevalence of PPTA was .54%. The Saltzman classification of PPTAs was as follows: type I, 24%; type II, 16%; type III, 60%. Sixteen percent of the cases with PPTA were accompanied with intracranial aneurysm. CONCLUSION: A 3D-TOF MRA at 3.0 T can be used for the detection of PPTA and making a classification of PPTA indirectly. The incidence of PPTA with type III was greater than that of other types of PPTA. Intracranial aneurysm appeared to be associated with PPTA.