Objective To discuss the safety and curative effect of CT -guided percutaneous argon -helium cryoablation in treating leiomyosarcoma. Methods A total of 25 patients with leiomyosarcoma, who were treated at authors' hospital during the period from January 2012 to January 2016, were included in this study. CT-guided percutaneous argon-helium cryoablation was performed in all patients. The local changes of target lesions, the progression - free survival (PFS) and the survival rate were dynamically checked, and the complications were recorded. Results CT examination performed immediately after argon- helium cryoablation indicated that radical frozen ablation was achieved in 13 patients (52％), significant tumor -reductive frozen ablation in 11 patients (44％), effective tumor-reductive frozen ablation in one patient (4％), and invalid tumor-reductive frozen ablation in 0 patient. Follow - up CT examination performed at 3 months after argon - helium cryoablation showed that, based on solid tumor evaluation criteria, complete remission (CR) was obtained in 14 patients, partial remission (PR) in 8 patients and stable disease (SD) in one patient, the total remission rate (CR+PR) was 88％. The local PFS time was (9. 4±6. 2) months. The one-, 2-and 3-year survival rates were 64％, 48％ and 32％ respectively. In this group of cases, neither serious complications such as haemorrhage or tumor lysis syndrome nor procedure-related death occurred. Postoperative mild and moderate complications included fever, skin frostbite, immediate postoperative local pain exacerbation, nerve damage, etc., all of which disappeared or became relived after symptomatic treatment. Conclusion For the treatment of leiomyosarcoma, CT-guided percutaneous targeted argon-helium cryoablation has certain and definite short-term curative effect. CT-guided argon-helium cryoablation is a safe, reliable and minimally-invasive treatment, this technique is worth popularizing in clinical practice. (J Intervent Radiol, 2018, 27:228-232)

Objective:To evaluate the influence of age factors on dose-effect relationship of oxycodone inhibiting responses to tracheal intubation during induction of general anesthesia in pediatric patients.Methods:American Society of Anesthesiologists Physical Status classification Ⅰ or Ⅱ pediatric patients of both sexes, aged 6 months-6 yr, with body mass index of 12-22 kg/m 2, scheduled for elective surgery under general anesthesia with tracheal intubation, were divided into 3 groups: infant group (group I, 6-12 months), young children group (group Y, >1-3 yr) and preschooler group (group P, >3-6 yr). Oxycodone was slowly injected intravenously, 2 min later etomidate 0.3 mg/kg and cisatracurium 0.15 mg/kg were intravenously injected, and 3 min later endotracheal intubation was carried out with a visual laryngoscope in all the children. Mean arterial pressure(MAP) and heart rate (HR) immediately before intubation and peak MAP and HR within 3 min after intubation were recorded. The modified Dixon′s sequential method was used. The initial dose of oxycodone was 0.3 mg/kg in each group. If the response to tracheal intubation was positive, the dose of oxycodone was increased by 0.02 mg/kg in the next child; if the response to tracheal intubation was negative, the dose of oxycodone was decreased by 0.02 mg/kg in the next child. Positive response to tracheal intubation was defined as increase in MAP and/or HR and increase in the peak value exceeding 20% of the pre-intubation level within 3 min after tracheal intubation. The aforementioned process was repeated until 7 negative and positive reactions crossed, and then the test was stopped. The median effective dose (ED 50) and 95% confidence interval of oxycodone were calculated by Probit method. Results:The ED 50 (95% confidence interval) of oxycodone inhibiting responses to the tracheal intubation were 0.280 (0.247-0.301) mg/kg, 0.321 (0.304-0.342) mg/kg and 0.354 (0.342-0.368) mg/kg in I, Y and P groups, respectively. The ED 50 of oxycodone inhibiting responses to the tracheal intubation was gradually increased during induction of general anesthesia with increasing age ( P<0.05). Conclusions:For children aged 6 months to 6 yr, the potency of oxycodone in inhibiting responses to the tracheal intubation during general anesthesia induction gradually decreases with increasing age.

Objective: To evaluate the feasibility and short-term effect of CT guided cryoablation for malignant chest wall or pleural involvement. Methods: To follow up 22 patients with chest wall or pleural involvement of various malignancies who underwent cryoablation from January 2012 to January 2015 by conducting postoperative 1-, 3- and 6-month enhanced CT, MRI or PET-CT examinations, respectively, evaluate local curative effect, and observe their progression-free survival (PFS), postoperative pain remission and complications after the cryoablation. Results: A total of 22 patients with 27 lesions received 26 times of argon-helium cryoablation. According to the coverage situation of immediate postoperative ice balls on the lesions, they were divided into a complete coverage group (Group A with 18 patients) and a partial coverage group (Group B with 4 patients). 1 month later, 15 patients′ tumors were completely ablated, and 3 had residue and thus received the second cryoablation in Group A, while all patients′ tumors had residue in Group B. 3 months later, 17 patients′ tumors were completely ablated, and 1 had residue and thus received another cryoablation in Group A, while all patients′ residual tumors enlarged in different extent in group B. 6 months later, all lesions were ablated in group A while all patients′ residual tumors enlarged in group B. For the 22 patients, their preoperative, and postoperative 1-week, 1-month, 3-month, and 6-month VAS scores were 4.95±0.57, 1.45±0.35, 1.45±0.35, 1.64±1.71, and 2.00±2.35, respectively. The differences in the preoperative, postoperative 1-week, and postoperative 1-month scores are significant statistically (P<0.05), and the difference in the postoperative 1-month and 6-month scores is also with statistical significance (P=0.03). For all patients, their post-operative 1-week, 1-month, 3-monte and 6-month pain remission rates are 90.9%(20/22), 90.9%(20/22), 86.4% (19/22)and 81.8%(18/22), respectively. With a median follow-up of 13.5 months, the median PFS is 7 months. The adverse effect after argon-helium cryoablation involved transitory worsened pain (16 cases), pleural effusion (5 cases, including 3 underwent closed drainage), fever (5 cases), and hemoptysis (3 cases). Conclusion CT guided argon-helium cryoablation is a safe and effective method to treat malignant chest wall or pleural involvement.