Objective: To explore the effect of the aortic arch type on technical indicators in patients with carotid artery stent implantation.
Methods: We retrospectively analyzed 224 consecutive patients treated in Fu Wai hospital for unilateral carotid artery stent implantation from 2011-01 to 2012-12. We summarized the catheter category, type and the operating techniques including ① retracement, turn and insertion of the catheter, ② retracement, turn of catheter+the guidance of guide wire,③ retracement, turn of catheter+the guidance of guide wire+the supporting of another catheter, ④ using special graphic catheter+the guidance of guide wire+the supporting of another catheter. The procedural X-ray exposure time, dosage of contrast agent and operation related complications were recorded. According to Myla classiifcation, the aortic arches were divided into Myla I, Myla II and Myla III types.
Results: There were 7/224 (3.1%) patients with Myla I aortic arch, 113 (50.4%) with Myla II aortic arch and 104 (46.4%) with Myla III aortic arch. A total of 48/104 (46.2%) Myla III patients used special techniques (tech③, tech④), it was more than the patients with Myla I, (1/7,14.3%) and Myla II (17/113, 15.0%), P<0.01. The patients with Myla III aortic arch had the longer X-ray exposure time and used the higher dose of contrast agent, all P<0.01. The procedural success rate in patients with
Myla III was 96.2%, it was lower than those with Myla I (100%) and Myla II (100%), P=0.045. The procedural complication rate in patients with Myla III was 22.1%, it was higher than those with Myla I (0%) and Myla II (8.9%), P=0.007.
Conclusion: The aortic arch type is the important inlfuential factor for the techniques used in carotid stent implantation. There were more dififculties and complications for stent implantation in patients with Myla III aortic arch.

[Objective] To review the clinical information, imaging features, pathological manifestations and prognosis of low-grade oncocytic tumor (LOT), so as to improve the clinical understanding of the disease. [Methods] The imaging, clinicopathological and postoperative follow-up data of 3 LOT cases treated in Peking University Third Hospital during Feb.2020 and Sep.2022 were retrospectively collected. [Results] All patients were male, aged 51—70 years.All tumors were single, with the maximum diameter of 14—21 mm. None of the patients had any specific clinical manifestations.The mass showed a circular isodense shadow on CT.All patients underwent nephron-sparing tumor resection.Postoperative pathology showed that the incision surface of the tumors was brownish-yellow or brown, and the tumors were solid or partially cystic.HE staining showed that the cells were uniformly eosinophilic; the nucleus was round or oval, with slight local perinuclear halo.Immunohistochemistry showed positive CK7 but negative CD117.Genetic testing in case 2 showed 1 potentially clinically significant somatic mutation TSC2.During the follow-up of 12-23 months, no recurrence occurred. [Conclusion] There were no obvious clinical symptoms and imaging features of LOT, which morphologically showed heterozygous or borderline characteristics with renal eosinophilia and renal chromophobe cell carcinoma, and the biological behavior was indolent.Nephron-sparing tumor resection promised good prognosis.