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911.
Ryu JK Woo SM Hwang JH Jeong JB Yoon YB Park IA Han JK Kim YT 《Diagnostic cytopathology》2004,31(2):100-105
Pancreatic cystic neoplasms comprise a pathologically heterogeneous group with many shared clinical features. We assessed the reliability of cyst fluid analysis for the differential diagnosis of pancreatic cysts. Cyst fluid was obtained by fine-needle aspiration from 78 pancreatic cysts. The lesions studied consisted of 17 mucinous cystic tumors (MCTs), 13 serous cystadenomas (SCAs), 5 solid pseudopapillary tumors (SPTs), 8 intraductal papillary mucinous tumors (IPMTs), 6 ductal adenocarcinomas (ACAs) with cystic degeneration, and 29 pseudocysts (PCs). Epithelial cells were observed in 27 (81%) of 33 successful aspirates of cystic neoplasms. Cytologic diagnosis was possible in 5 (31%) out of 16 MCTs. Mucicarmine staining was positive in five out of nine MCTs, one out of one ACA, and one out of two IPMTs, but in none of the SCAs, SPTs, or PCs. Cyst fluid carcinoembryonic antigen (CEA) levels of more than 467 ng/mL had a 87% sensitivity and a 98% specificity for detecting MCTs, and amylase levels of more than 479 U/L had a 73% sensitivity and a 90% specificity for detecting PCs. In conclusion, cyst fluid analysis for cytology, mucin staining, CEA, and amylase levels are useful in the differential diagnosis of pancreatic cysts. 相似文献
912.
Shevell T Malone FD Weintraub J Thaker HM D'alton ME 《American journal of obstetrics and gynecology》2004,190(2):575-576
Radiofrequency ablation is a minimally invasive technique that has been used in selective reduction of acardiac twins. We report a case in which radiofrequency ablation was used to selectively reduce a monochorionic twin discordant for an abnormality. 相似文献
913.
Miller KA Elkind-Hirsch K Benson M Bergh P Drews M Scott RT 《Fertility and sterility》2004,81(1):191-193
OBJECTIVE: To compare the effectiveness and tolerability of two different 17-gauge follicle aspiration needles used in a large in vitro fertilization (IVF) program. DESIGN: Prospective, randomized single blinded study. SETTING: Private IVF center. PATIENT(S): Three hundred women undergoing IVF were randomly allocated at the time of oocyte retrieval to either the study needle (n = 151; follicle aspiration set [FAS] set) or the standard needle (n = 149; Echotip) used in the practice. Patients were blinded to the needle used.INTERVENTION(S): Transvaginal ultrasound-guided oocyte aspiration. MAIN OUTCOME MEASURE(S): Number of eggs retrieved/follicles visualized, retrieval time, mean amount of blood in the aspirate, egg damage, patient tolerance, physician acceptability, implantation, and pregnancy rate. RESULT(S): No differences were found in the number of eggs retrieved normalized to follicles visualized. Egg damage (4% vs. 4.2%), average blood in the aspirate (2.2 vs. 2.2), and retrieval time per egg (38 vs. 36 seconds) were similar with both needles. There were also no differences in pain or cramping scores (at 30 minutes and 24 hours after retrieval) or in the physicians' ratings of the two needles. The percentage of patients receiving an embryo transfer (ET), the implantation rate per embryo transfer, and the clinical pregnancy rate per embryo transfer were comparable for both needles. CONCLUSION(S): The FASs are equivalent. 相似文献
914.
Our purpose was to compare the effects of percutaneous radiofrequency ablation (RFA) combined with percutaneous ethanol injection (PEI) on the extent of ablation in in vivo rabbit liver tissue as compared with either therapy alone. Twenty-two New Zealand white rabbits were included in this study and allocated into three groups: group A: conventional RFA (n = 6); group B: PEI (n = 6); group C: combined RFA and PEI (n = 10). For combined RFA and PEI, under ultrasound guidance, 1 mL of absolute ethanol was injected into the target area of the liver parenchyma through a 21-gauge Chiba needle before performing RFA. RFA was performed using a 17- gauge internally cooled electrode with 1-cm active tip, and RF energy (30 W) was applied for 3 minutes, with or without ethanol injection. After RFA or PEI, contrast-enhanced computed tomography and CT-pathologic correlation were performed. The short- axis and long-axis diameters of thermal lesions of each group were compared. All procedures were technically successful and a total of 38 lesions were produced. The mean short-axis and long-axis diameter of the coagulation necrosis in rabbits of group C (combination of RFA and PEI), were significantly larger than those of other groups: group A: 10.3 ± 2 mm and 11.4 ± 2 mm; group B: 3.1 ± 1 mm and 4.3 ± 2 mm; group C: 12.8 ± 3 mm and 17.8 ± 6 mm (p < 0.05). On contrast-enhanced CT scan, the lesions of rabbits of the group C appeared to be more frequently irregular compared to those of group A (20% in group A vs. 67% in group C). There were three complications including two localized hematomas and one cardiopulmonary failure. Combined RFA and PEI could increase the dimension of coagulation necrosis without increasing complications and therefore, may be successfully used for treating larger lesions. 相似文献
915.
Veltri A De Fazio G Malfitana V Isolato G Fontana D Tizzani A Gandini G 《European radiology》2004,14(12):2303-2310
Minimally invasive treatment for small renal cell carcinoma (RCC) can be necessary in selected patients and, anyway, is desirable. In situ ablation techniques, including RFA, have been developed. The aim of this study is to evaluate the feasibility, safety and short-term local effectiveness of percutaneous US-guided RFA in a small series, as well as mid-term patient outcome. Thirteen patients with a total of 18 tumors (17 small lesions, 35 mm in size or less, and a larger one, 75 mm in size) underwent 19 RFA sessions. Seven patients had a solitary kidney, and three suffered from VHL disease, too. We treated four lesions in a patient with a bilateral tumor. In another patient, three lesions were ablated. Seventeen tumors were RCC; one was a metastasis from lung cancer. Eight lesions were parenchymal, six exophytic, two parenchymal/exophytic, one parenchymal/central and one central. A monopolar RF system with multitined expandable electrode needles was used. The 35-mm lesion underwent two sessions; the 75-mm lesion was treated with transcatheter arterial embolization before RFA. Tumors with complete loss of contrast enhancement at short-term CT (or MR) were considered successfully treated. Percutaneous US-guided RFA was always feasible without major complications. The success rate after a single treatment in tumors less than 35 mm in size was 88.2% (15/17) and rose to 94.1% (16/17) after the second treatment of the largest lesion. After a mean 14-month follow-up, no successfully treated lesions recurred locally. Only the patient with metastasis from lung cancer died from disease progression in a further location, while all other patients are alive, with renal function still sufficient to avoid dialysis. US guidance allows an easy and safe percutaneous approach for RFA of small non-parahilar RCC. The treatment is locally effective and can be proposed as a minimally invasive therapy for patients with contraindications to surgery or to those expressing an informed consent. Based on the results of this study and of the literature, mid-term results on the clinical usefulness are very encouraging.Presented at ECR 2003. 相似文献
916.
Laparoscopic staging and tumor ablation for hepatocellular carcinoma in Child C cirrhotics evaluated for orthotopic liver transplantation 总被引:1,自引:0,他引:1
Background: Surgical resection and liver transplantation remain the only treatments that offer cure for hepatoma, but are limited to those with early stage disease. Prelisting radiological staging is not always definitive. In this study, we sought to delineate the role of laparoscopy for clarification of staging in advanced cirrhotic patients when radiological assessment during evaluation for orthotopic liver transplants (OLTx) is equivocal. Methods: Over a 3-year period, 18 patients with advanced liver insufficiency being evaluated for OLTx listing underwent laparoscopic staging when the following criteria were met: (1) lesion(s) with indeterminate size/borders, (2) an indeterminate number of lesions, or (3) lesion(s) and alpha-fero protein (AFP) less than 100 ng/ml. Patients underwent exploratory laparoscopy and laparoscopic ultrasound with biopsy, with or without ablation of lesion(s). Results: Laparoscopic staging was initiated in 18 patients; four of the first six patients were converted to open procedures. Twelve patients were restaged as a result of the procedure: six down-staged and six up-staged. Stage changes were based on laparoscopic visualization of advanced disease in two, ultrasonographic clarification of tumor size/number in seven, and biopsy in three. Twelve of the 14 laparoscopic procedures included laparoscopic radiofrequency ablation while one received ethanol ablation. One patient required 2 units of red blood cells. One patient died on postoperative day 7 because of gastrointestinal bleeding. Four of the six down-staged patients underwent liver transplant, and pathological staging of the explants agreed with laparoscopic staging in all cases. Conclusion: Laparoscopic staging for HCC in advanced cirrhosis can clearly characterize tumor burden when preoperative radiological assessment is equivocal. 相似文献
917.
Percutaneous Imaging–Guided Radiofrequency Ablation in Patients With Colorectal Pulmonary Metastases: 1-Year Follow-Up 总被引:5,自引:2,他引:3
Steinke K Glenn D King J Clark W Zhao J Clingan P Morris DL 《Annals of surgical oncology》2004,11(2):207-212
Background: We assessed the safety and evidence of efficacy of radiofrequency ablation (RFA) for colorectal lung metastases with follow-up to 1 year.Methods: Twenty-three patients had percutaneous RFA for 52 colorectal pulmonary metastases under fluoro-computed tomography (CT). Patients received intravenous conscious sedation and local analgesia with routine hospitalization and monitoring for 24 hours after RFA. Patients had CT scanning at 1 month and then every 3 months, with serum carcinoembryonic antigen assessment monthly and every 3 months.Results: All ablations were technically successful. Tumor diameter ranged from .3 to 4.2 cm. Pneumothorax occurred in 43% (10 of 23) of patients. Six patients required intercostal chest drain placement. Six patients had a second RFA, four for new lesions and two for re-treatment of a previously treated lesion. The median admission was 2.0 days (range, 1–9 days). The median follow-up was 428 days (range, 173–829 days); data are reported to 1 year in this article. Five patients died at 5, 6, 8, 8, and 12 months after RFA from extrapulmonary (n = 1) or widespread (n = 4) disease. One patient developed a malignant pleural effusion at 6 months after RFA. Cavitation was seen in nine treated lesions (17%); all resolved with scar tissue contraction by 12 months. Eighteen patients with CT scan follow-up at 1 year have 40 lesions classified as disappeared (n = 17), decreased (n = 5), stable/same size (n = 4), or increased (n = 14).Conclusions: Percutaneous imaging–guided RFA of multiple colorectal pulmonary metastases is a minimally invasive treatment option with modest morbidity. A significant proportion of patients show good evidence of successful local control at 1 year. 相似文献
918.
Atypical glands on prostate needle biopsy with a negative 34betaE12 (cytokeratin 903; CK903) immunostain, indicating a lack of a basal cell layer, are typically diagnostic of prostate cancer. However, in certain cases a negative 34betaE12 immunostain in a small focus of atypical glands is still not convincing enough to make the diagnosis of cancer. This study is the first report to evaluate the incidence of prostate cancer on follow-up biopsy in individuals with this diagnosis. A total of 543 men who had prostate core biopsy specimens diagnosed as a small focus of atypical-appearing glands with a negative 34betaE12 immunostain between January 1, 1997 and December 31, 2000 were selected for study. Some 61% of these 543 individuals (n = 332) had undergone at least one follow-up biopsy procedure. Of these, 43% of repeat biopsy cases (n = 142) were diagnostic of prostate cancer. A total of 46 individuals had at least 2 follow-up biopsy procedures, with 48% of these (n = 22) being diagnosed as cancer. The Gleason grades of the detected carcinomas were broken down as follows: Gleason grade 3 + 2 = 5, 6%; grade 3 + 3 = 6, 86%; grade 3 + 4 = 7, 1%; grade 4 + 3 = 7, 4%; and grade 4 + 4 = 8, 3%. The median amount of time to the first follow-up biopsy was 79 days, with 52% of follow-up biopsies performed within 90 days. A negative 34betaE12 immunohistochemical stain in a small focus of atypical glands is not associated with an increased prediction of prostate cancer on follow-up biopsy (43%), compared with previously published data for "small focus of atypical glands" alone (approximately 45%). Because 48% of men with an initial negative biopsy and multiple follow-up biopsy procedures were found to have cancer, more than one repeat biopsy session or more extensive sampling on the first repeat biopsy procedure may be necessary to maximize the identification of cancer. This finding is similar to that found in men with atypical diagnoses in general, without a negative 34betaE12 immunohistochemical stain. Only half of all individuals with a diagnosis of 34betaE12-negative focus of atypical glands underwent repeat biopsy within 3 months. Urologists need to be educated as to the significance of an atypical diagnosis and the need for repeat biopsy. In a small focus of atypical glands on prostate biopsy, negative staining for 34betaE12 should not necessarily lead to a definitive malignant diagnosis in all cases, because almost half of these biopsies on follow-up sampling are benign. 相似文献
919.
Evaluation of needle exchange programs 总被引:1,自引:0,他引:1
Delgado C 《Public health nursing (Boston, Mass.)》2004,21(2):171-178
Needle exchange programs exist in every major population area in the United States and in many other countries. Some operate legally under emergency health decrees issued by local departments of health, with the stated intention of risk reduction through the removal of used injection equipment from use by injection drug users. It is theorized that this results in a reduced transmission of human immunodeficiency virus, hepatitis, and, possibly, other blood-borne diseases. Needle exchange programs also offer access to drug treatment programs for the participants. It is a difficult but necessary task to evaluate these programs. This article examines examples of evaluations attempted in the past and discusses the challenges of such evaluations. Experimental evaluations, economic program analysis, legal aspects, and risk-benefit assessment along with ethical aspects are considered. An outline of program evaluation is proposed. Needle exchange programs offer an opportunity to encourage risk reduction and to offer counseling and access to health care for individuals at high risk. It is essential that such programs demonstrate their effectiveness. Assumptions of efficacy are insufficient for health care in the twenty-first century. 相似文献
920.
目的研究经不同方法局部注射131I-碘化油后对瘤体的损伤效应.方法建立SMMC-7721肝癌皮下移植瘤大鼠模型,分别采用直形注射针线状退行注射(3条线)和弧形套针单点分段旋转扇形注射法,经皮向肿瘤内注射131I-碘化油(0.1×37 MBq/cm3),观察给药后一定时间段大鼠体重、肿瘤大小的变化和动物存活时间,同时以穿刺针和小剪刀取材按常规方法制备病理切片和超薄切片,观察并比较两种给药方法肿瘤组织的形态学变化. 结果直形针给药组大鼠在注射后2周多数表现为体重下降,肿瘤增大,最后都死于全身耗竭;而弧形针组大鼠体重相对稳定,肿瘤组织表现为均匀坏死,缓慢崩溃,动物存活期明显比前者长.直形针给药组肿瘤组织早期表现为大片的组织坏死,晚期表现为存活区域的增加,坏死区域与存活区域界限分明,两者间多有移行带;弧形针分段扇形注药者早期、晚期组织均表现为大片坏死,肿瘤间质内可见淋巴细胞浸润和纤维结缔组织增生;各时间段的检测标本中都可见一定数量的凋亡细胞,但比例远远小于坏死的肿瘤细胞. 结论弧形针分段扇形注射是较为理想的给药方式;"坏死"是治疗剂量131I-碘化油内放疗对瘤体的主要损伤效应. 相似文献