Objective To studying the MR findings and pathology of peripheral small intrahepatic cholangiocarcinoma and improving the understanding of peripheral small cholangiocarcinoma with no-bile duct dilatation. Methods A retrospective analysis of 12 patients with intrahepatic peripheral cholangiocarcinoma which were confirmed by surgery and pathology, all patients were examined by abdominal MRI without and with contrast. Correlation was made with gross pathology and surgical pathological specimen. Results On T1WI, there were 4 cases of complex low signal intensity and 8 cases of low signal intensity. On T2WI, there were 8 cases of high signal intensity and 4 cases of complex high signal intensity. Enhanced MRI showed: marked nidus enhancement on arterial phase in 1 case, and the pathological diagnosis was poorly differentiated adenocarcinoma. Inhomogeneous enhancement or annular enhancement were seen in 10 cases on arterial phase, 3 of these cases showed thin annular enhancement on arterial phase, low signalintensity on portal venous phase and isointensity on delayed phase. One case showed delayed enhancement. Thick circular enhancement correlated with pathological changes of survival of tumor cells, center areas correlated with fibrous connective tissue, and a small amount of necrotic tissue. Island-like enhancement or inhomogeneous enhancement were seen in 3 cases. Corresponding pathological changes consisted of tumor tissue and a small amount of fibrous connective tissue, as well as somenecrotic tissue. In 1 case, no enhancement was seen on all three phases and pathological changes showed cystic changes, hemorrhage, necrosis, with survival tumor cells seen between cyst and normal liver tissue. Conclusions MRI scanning of peripheral small cholangiocarcinoma lacked characteristic features, but dynamic contrast-enhanced MR had certain specific findings. Due to different pathology, the fibrous tissue, necrotic tissue and survival tumor tissue components were exhibited different imaging findings.

Objective:To study the strategy of endovascular treatment for patients with the risks of internal carotid artery (ICA) rupture and bleeding during the treatment of nasopharyngeal carcinoma (NPC) based on American Society of Intervention and Therapeutic Neuroradiology/Society of Interventional Radiology (ASITN/SIR) grade of collateral circulation.Methods:A total of 56 patients (45 males and 11 females, aged from 28 to 76 years old) diagnosed with nasopharyngeal carcinoma and admitted to the Department of Neurosurgery, the Third Affiliated Hospital of Southern Medical University from July 2018 to January 2020 were retrospectively analyzed. There were 15 cases of ASITN/SIR grade 4, 24 cases of ASITN/SIR grade 3, 5 cases of ASITN/SIR grade 2, 5 cases of ASITN/SIR grade 1, and 7 cases of ASITN/SIR grade 0. The events of stroke and death were analyzed statistically.Results:ALL patients with ASITN/SIR grade 4 or 3 and some of patients with ASITN/SIR grades 2-0 passed balloon occlusion test and electrophysiological monitoring. ICA pseudoaneurysm was found in 35 patients, and one-stage ICA embolization was performed in 29 patients after evaluation. Among them, 8 cases of ASITN/SIR grade 4 and 10 cases of ASITN/SIR grade 3 with obvious posterior circulation compensation obtained successful one-stage ICA embolization without cerebral ischemia; cerebral ischemic events occurred in 5 (55.6%) of 9 patients with ASITN/SIR grade 3 and in 1(50.0%) of 2 patients with ASITN/SIR grade 2. The total incidence of ischemic events was 20.7% (6/29) and 1 case was disabled (1/29, 3.4%). Among patients with ASITN/SIR 3, there were statistically significant differences in stroke event rate between patients with obvious posterior circulation compensation and patients with slight or without posterior circulation compensation (0/10 vs. 5/9, χ 2=4.95, P=0.026). Follow-up time was 10.1±7.8 months, and 46 patients were survival (46/56, 82.1%) and 10 patients died (10/56, 17.9%) with a mean survival time of 2.6±1.4 months. Conclusions:For NPC patients with ICA invasion, ASITN/SIR based on DSA can simplify the assessment process of cerebral blood flow compensation. ICA can be embolized directly in patients with ASITN/SIR 4 or 3 with obvious posterior communicating compensation.