Usually experiments done on isolated working heart preparation must be completed within 1 h, because of declining of cardiac functions after going beyond that limit reported by many authors. Our experiments on guinea pig showed that the viability time lasted at least 2 h. All measured indices of cardiac performance, namely LVP, dP/dtmax, MASP, HR, CF, AF, CO, LVPW, MVO2 and. working efficiency, remained stable within that period of time, .when PcO2 and PO2 of perfusing solution were adjusted at 4.7~7.3 kPa and over 67 kPa respectively, resulting in stability of pH value in 7.4 or so. Modification of the Krebs solution by devoid of phosphate and addition of pyruvate and EDTA may also be responsible for prolongation of the viability time. After such improvement, the preparation will give sufficient time to study the effect of drugs. Its use will be greatly widened.1 -10 mg/L cobra cardiotoxin increased CO, AF, LVEDP, MASP, LVP, dP/dtmax, decreased CF, and unchanged HR.MVO2 and working efficiency were insignificantly increased. These results obtained from this preparation were in accordance with that from other isolated cardiac preparations.

Objective To evaluate the efficacy of percutaneous CT-guided puncture and steroid injection for the treatment of lumbar intraspinal synovial cysts (LISCs).Methods A patient with clinical symptom of LISCs was undergone percutaneous CT-guided lumbar synovial cyst puncture. After aspiration of the content and steroid injection were accomplished, visual analogue scale was used to evaluate the pain of the patient before and after the treatment.Results Excellent pain relief after aspiration and steroid injection was obtained with the symptom disappearing 4 days after the treatment.Conclusions Aspiration and steroid injection can reduce the pain of the patient with lumbar intraspinal synovial cysts,and it should be the frist choice of non-surgical treatment.

Objective To identify the short and long-term therapeutic benefits of CT-guided transforaminal epidural steroid injections in lumbar spinal stenosis. Methods Thirty six patients with lumbar spinal stenosis shown by CT underwent CT-guided transforaminal epidural steroid injections because of irresponsible to conservative treatment. Patients were evaluated by visual analogue scale (VAS) before the initial injection, at 2 weeks and 1 year after the injection.Results All patients were followed up for 2 weeks and 1 year. 19 ( 52.8%) patients had successful short-term outcome, and 15 ( 41.6%) had long-term outcome. 15 ( 41.6%) patients satisfied with the short-term result and 12 (33.3%) were satisfactory with the long-term result.Conclusions CT-guided transforaminal epidural steroid injection may reduce the pain and improve the quality of life in some patients with lumbar spinal stenosis.

Implantation of radioactive seeds is an effective therapeutic option for the treatment of malignant tumors. With the development of imaging technique and the use of treatment planning system (TPS) it has been more and more employed in clinical settings. The technique has been widely practiced in various malignant tumors, such as prostate cancer, lung caner, pancreatic cancer, hepatocarcinoma, etc. In order to standardize the clinical application of this technology, the authors propose some suggestions concerning the management of radioactive seeds, the indications and contraindications as well as the method of operation as a technical guidance.

Objective to explore the safety and clinical efficacy of CT-guided radioactive seed implantation in treating recurrent rectum carcinoma. Methods CT-guided ~(125)I radioactive seed implantation was carried out in 20 patients with recurrent rectal carcinoma. Treatment planning system was used preoperatively to reconstruct three dimensional image of the tumor and to calculate the estimated seed number and distribution. The tumor matched peripheral dose (MPD) of the radioactive seeds was 80-130 Gy. The radioactivity of the seeds was 0.5-0.8 mCi/seed and the median implanted seeds was 48 (range 25-95) in number. CT scan was made immediately after the implantation to check the quality of the seeds. Change of pain score, tumor size and complications were recorded during the follow-up period. Results Twenty cases composed of 12 males and 8 females, aged 38 to 78 years (median age of 62 years). The follow-up period lasted 2-28 months. On an average, 3 to 7 days after the procedure patients experienced significant pain relief. CT scan performed 2 months after the procedure revealed that complete relief (CR) of the tumor was seen in 2 cases, partial relief (PR) in 13 cases, no change (NC) in 3 cases and progression (PD) in 2 cases. The total effective rate (CR + PR) was 75%. The median survival time was 18.8 months. The survival rate of 1 and 2 years was 75% and 25% respectively. Two cases died of tumor deterioration and 3 cases died of extensive metastases. No complications such as frequent micturation, pain on urination and hematuria occurred during the follow-up period. Conclusion CT-guided ~(125)I radioactive seed implantation is a safe and effective interventional treatment for recurrent rectal carcinoma with reliable short-term efficacy and excellent anti-pain effect.

Objective To investigate the safety and clinical efficacy of CT-guided radioactive ~(125)I seed implantation treatment for advanced lung cancer. Methods The clinical data of thirty cases with lung cancer, which was proved by puncture biopsy, histology or cytology, were retrospectively analyzed. The pathologic diagnoses included squamous cell carcinoma (n= 13), adenocarcinoma (n= 8) and metastatic lung cancer (n= 9). Using treatment planning system (TPS) 3D images of the tumor were reconstructed, the number and the dose rate distribution of ~(125)I seeds were calculated. The matched peripheral dose (MPD) of ~(125)I seed implantation was 80-130 Gy. The median amount of implanted ~(125)I seeds was 35 (8-83) in number. Results Follow-up observation was made at 1, 3, 6 and 12 months after the treatment in all patients. The median survival time was 12 months (7-18 months). The cumulative survival rate at 6, 9 and 12 months was 100.0%, 80.0% and 23.3%, respectively. Follow-up CT images 12 months after the therapy showed that complete relief (CR) was seen in 9 cases, partial relief (PR) in 14 cases, no change (NC) in 4 cases and progression (PD) in 3 cases. The overall effective rate (CR + PR) of 1-month, 3-month, 6-month and 12-month was 83%, 80%, 80% and 77%, respectively. During following-up period, pneumothorax occurred in 3 cases and bloody sputum occurred in 7 cases. Conclusion CT-guided radioactive ~(125)I seed implantation treatment is a safe, effective and minimally-invasive treatment for lung cancer.

Objective To discuss the clinical efficacy of CT-guided radioactive ~(125)I seed implantation treatment for unresectable pancreatic cancer. Methods Forty patients with inoperable pancreatic cancer were enrolled in this study, including 25 males and 15 females with an median age of 69 years (38-89 years). Treatment planning system (TPS) was used to reconstruct 3-dimensional images of pancreatic tumor and to define the quantity and distribution of ~(125)I seeds. The radioactivity of ~(125)I seeds was 0.5-0.8 mCi/seed. The seeds were implanted into pancreatic tumor under CT guidance at intervals of 1 cm and were kept away from vessels, pancreatic duct and other adjacent important organs. The tumor matched peripheral dose (MPD) was 60-140 Gy. The median amount of implanted ~(125)I seeds was 36 (18-68) in number. CT scan was performed immediately after the procedure to check the quality of the seeds. In addition, 10 patients received concurrent chemotherapy with arterial infusion of gemcitabin and 5-fluororacil (5-Fu) for 3 to 4 therapeutic courses. Results The median diameter of the tumors was 4.9 cm. The follow-up period was 2 to 28 months. After the treatment the refractory pain was significantly relieved (P < 0.05), and Karnofsky score was dramatically increased (P < 0.05). Most patients experienced relief of pain within 2-5 days after implantation. Two months after treatment, on CT scans the tumors showed completed relief (CR) in 3 cases, partial relief (PR) in 20 cases, no change (NC) in 14 cases and progression (PD) in 3 cases. The overall effective rate (CR+PR) was 57.5%. The median survival time for all patients was 10.2 months, while it was 14.7 months, 10.9 months and 7.1 months for patients in stage Ⅱ, stage Ⅲ and stage IV respectively. For patients in stage Ⅱ, stage Ⅲ and stage Ⅳ, the 6-month cumulative survival rate was 100%, 88% and 62% respectively, while the 12-month cumulative survival rate was 70% , 41% and 0% respectively. After the therapy, liver metastasis occurred in 5 cases and chemoembolization was employed. In three patients, immigration of four radioactive seeds to the liver was found. No serious complications, such as upper GI bleeding, pancreatitis, pancreatic fistula formation and radiation colitis, occurred during the follow-up period. Conclusion CT-guided radioactive ~(125)I seed implantation is a safe, effective and minimally-invasive brachytherapy for unresectable pancreatic cancer with reliable short-term efficacy. It has an excellent anti-pain effect. The curative results can be further improved when chemotherapy is employed together. However, its long-term efficacy needs to be observed.

Objective To evaluate the effects of misregistration with different directions and magnitudes between SPECT and CT on image quality and semi-quantification of MPI.Methods The data of 19 healthy volunteers (11 males,8 females ; mean age:(65.3 ± 9.6) years) were retrospectively analyzed.They all had a low pretest likelihood of coronary artery disease according to exercise and rest 99Tcm-MIBI MPI.The CT attenuation correction (CTAC) was performed on a SPECT/CT system.The CT images were manually shifted by 0.5,1.0,1.5,2.0,2.5,3.0,3.5,4.0,4.5 cm distance along the up/down,left/ right,and anterior/posterior axes respectively by using the system built-in software.The counts of the left ventricle were measured using myocardial Bull's eye generated from the reconstructed CTAC images.The image quality and semi-quantification of the CTAC images reconstructed from the raw data with and without shifting were compared and analyzed.Paired t test was used to analyze the data.Results There was no visible artifact with 0.5 cm shifting.The image quality was deteriorated significantly and the counting difference was significant with shifting distance greater than or equal to 1.0 cm.The image artifact of apex wall was mainly due to the upward shift,anterior and apex wall due to the downward shift,septal wall due to the leftward shift,anterior,apex and lateral wall due to the rightward shift,lateral and infero-posterior wall due to the forward shift,anterior,apex and septal wall due to backward shift.The counting difference caused by the downward shift was significantly more severe than that caused by the upward shift ((-9.68±8.06) ％ and (-2.04±1.83)％,t=6.573,P＜0.01) ; and the rightward shift was more severe than the leftward shift ((-9.02± 8.47) ％ and (-4.38±3.67) ％ ; t =1.987,P＜0.05).The image artifacts in anterior,apex and lateral walls were more severe than those in the infero-posterior and septal walls.Conclusions CTAC image artifacts in myocardial perfusion SPECT/CT studies could be caused by misregistration ≥ 1.0 cm.Different directions and magnitudes of shift could result in different degrees of attenuation artifacts at different locations on the original images.

Objective To explore the value of right lateral decubitus position MPI for differentiating myocardial perfusion defect from cardiac anterior wall attenuation artificial defect,caused by breast of woman.Methods Forty-nine patients(average age (61.5±8.4) years) who had low likelihood of coronary artery disease and had perfusion defect in the anterior wall after exercise stress 99Tcm-MIBI MPI were included.All underwent supine and right lateral decubitus position during resting SPECT images.The myocardial perfusion SPECT images at left ventricle were reconstructed and were measured by Bull's-eye,based on the counts.Results from both supine position imaging and right lateral decubitus position imaging were compared.Paired t test was used to statistically analyse the data by SPSS 13.0.Results Compared with supine position,the counts of the anterior,inferior,apex and lateral wall in right lateral decubitus position were significantly higher:(71.30±3.53) ％ vs (66.50±3.85) ％,(70.06±4.45) ％ vs (65.44±4.16) ％,(77.90±3.00)％ vs (75.81±4.08)％,(79.30±2.26)％ vs (72.60±3.87)％ (t=6.731,5.286,3.555,10.885,all P＜0.01).The counts of septal wall were significantly lower ((66.60±3.98)％ vs (70.06±4.51)％,t=-4.625,P＜0.01) in right lateral decubitus position than that in supine position.Among the different regions of anterior wall,the counts of the anterior-middle ((76.40 ± 3.80) ％ vs (68.60 ± 4.76) ％) and anterior-apex region ((77.10±3.24) ％ vs (69.00±3.54) ％) were significantly higher (t =9.916,8.870,both P＜0.01) in right lateral decubitus position than those in supine position,but there was insignificance ((56.94±6.06)％ vs (58.50±4.98) ％,t =-1.493,P＞0.05) at anterior-basal region.The artificial defect of different degrees in anterior wall was observed in all patients in supine position,23 cases (46.9％,23/49) showed artificial defect in the anterior-middle region and 16 cases (32.7％,16/49) in the anterior-apex region.All artificial defect showed radioactive filling in right lateral position imaging,12 cases(24.5％,12/49) filled markedly and 32 cases(65.3％,32/49) filled completely.Conclusions The artificial defects caused by breast of woman mainly present in anterior-middle region and in anterior-apex region of the anterior wall in supine position imaging.The right lateral decubitus position imaging can markedly improve these artificial defects.

Objective The study the multislice spiral computed tomography (MSCT) characteristics of gastric glomus tumor. Methods The clinical data of 8 patients with gastric glomus tumor were retrospectively analyzed, and the MSCT characteristics were observed. Results Among 8 patients, 3 cases were male and 5 cases were female, and the age was 25-67 years. The diameter of lesions were 1.3-3.5 cm, and lesions situated in the antrum of the stomach. Gastric glomus tumor showed strong enhancement in the arterial phase, and prolonged enhancement during multiphasic scans. Conclusions Gastric glomus tumor has some characteristics in MSCT. The prolonged enhancement during multiphasic scans of the subepithelial lesion should be suspected of the gastric glomus tumor.