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61.
RATIONALE AND OBJECTIVES: To determine the incidence of radiology resident preliminary interpretation errors for plain film, body computed tomography, and neuroradiology (neuro)computed tomographic examinations read on call. MATERIALS AND METHODS: We retrospectively reviewed the data in a prospectively acquired resident quality assurance (QA) database dating between January 2000 and March 2007. The database comprises all imaging studies initially interpreted by an on-call resident and later reviewed by a board-certified attending radiologist who determined the level of discrepancy between the two interpretations according to a graded scale from 0 (no discrepancy) to 3 (major discrepancy). We reviewed the data with respect to resident training level, imaging modality, and variance level. Statistical analysis was performed with chi(2) test, alpha = 0.05. We compared our results with other published series studying resident and attending accuracy. RESULTS: A total of 141,381 cases were entered into the database during the review period. Of all examinations, 95.7% had zero variance, 3.3% minor variance, and 1.0% major variance. There was a slight, statistically significant increase in overall accuracy with increased resident year from 95.4% of examinations read by first-year residents (R1s) to 96.1% by fourth-year resident (R4s) (P < .0001). Overall percentages of exams with major discrepancies were 1.0% for R1s, 1.1% for second-year residents, 1.0% for third-year residents, and 0.98% for R4s. CONCLUSIONS: The majority of preliminary resident interpretations are highly accurate. The incidence of major discrepancies is extremely low and similar, even with R1s, to that of attending radiologists published in other studies. A slight, statistically significant decrease in the error rate is detectable as residents gain experience throughout the 4 years of residency.  相似文献   
62.
Gallbladder involvement in patients with renal cell carcinoma (RCC) is extremely rare. We present a report of a 61-year-old man with a synchronous RCC metastasis to the gallbladder presenting as an intraluminal polypoid mass simulating primary gallbladder carcinoma. Enhanced abdominal computed tomography demonstrated a well-enhanced polypoid lesion in the gallbladder. Intraoperative rapid pathological examination of the gallbladder tumor showed clear cell-type cancerous cells. Microscopically, tumor cells of both the resected kidney and gallbladder had round uniform nuclei, clear cytoplasm, and well-defined cytoplasmic borders, forming alveolar patterns. Immunohistochemically, the tumor cells were negative for cytokeratin 7 (CK7) and carcinoembryonic antigen (CEA), which is usually positive in primary clear cell carcinoma of the gallbladder. Therefore, the final diagnosis was RCC with a synchronous gallbladder metastasis.  相似文献   
63.
Bedside prediction of the central venous catheter insertion depth   总被引:1,自引:0,他引:1  
BACKGROUND: The carina level has been shown to be near the pericardial reflectionand can easily be identified as a landmark on a routine chestradiography. The purpose of this study was to reveal a simplemethod to predict the adequate central venous catheter (CVC)depth, hereby facilitating safe positioning of the CVC tip. METHODS: Central venous catheterization was performed via the right internaljugular vein (IJV) or the right subclavian vein (SCV). The CVCwas placed at a depth derived by adding the length between theneedle insertion point and the clavicular notch and the verticallength between the clavicular notch and the carina on the chestradiograph. The distance between the CVC tip and the carinawas measured on the postoperative chest radiograph. RESULTS: The tip position of 100 CVCs placed via the right IJV was 0.1(1.1) cm [mean (SD)] below the carina (95% CI: 0.3 cm belowcarina–0.2 cm above carina) and the tip positionof 153 CVCs placed via the right SCV was 0.0 (1.2) cm [mean(SD)] below the carina (95% CI: 0.2 cm below carina–0.2 cmabove carina). There were nine outliers (two in IJV group andseven in SCV group). CONCLUSIONS: When CVCs are inserted to a depth derived by adding the lengthbetween the needle insertion point and the clavicular notchand the vertical length between the clavicular notch and thecarina, the CVC tip can be reliably placed near the carina level.  相似文献   
64.
Background Endoscopic resection (ER) is an effective treatment for early gastric cancer (EGC) without lymph node metastasis. However, after ER additional surgery may be needed to manage the risks presented by residual cancer or lymph node metastasis. Methods ER was performed on 344 gastric adenocarcinomas between November 2001 and April 2006 at the Korean National Cancer Center under the strict pre-procedural indication. The authors performed operations in 43 patients due to: residual mucosal cancer, a mucosal cancer larger than 3 cm, or a submucosal cancer regardless of size or margin involvement. ER and surgical specimens were reviewed and analyzed for residual cancer and lymph node metastasis. Results Based on examinations of ER specimens, cancer was confined to the mucosal layer in 15 patients (34.9%) and invaded the submucosal layer in 28 patients (65.1%). Surgical specimens showed residual cancer in 17 patients (39.5%) and lymph node metastasis in four (9.3%). Neither residual cancer nor lymph node metastasis was found in patients with less than 500 μm submucosal invasion without margin involvement in ER specimens. In three of four patients with lymph node metastasis, the depth of submucosal invasion was 500 μm or more; the remaining patient had a 4-cm-sized differentiated mucosal cancer. Conclusions When a pathologic evaluation of an ER specimen reveals more than 500 μm of submucosal invasion or a mucosal cancer of larger than 3 cm, surgery should be considered due to the risk of lymph node metastasis.  相似文献   
65.
We evaluated erectile haemodynamics in mice and characterized the corpus cavernosum morphologically. Four-month-old male BALB/c mice and Sprague-Dawley rats were used. The following stimulation parameters were tested to achieve maximal erectile responses: voltage, 1-6 V; frequency, 6-24 Hz; pulse width, 1 msec; duration, 1 min (n = 7 per group). In a separate group of mice and rats (n = 10 per group), we measured systemic arterial pressure by use of either a 24-gauge angiocatheter or smaller calibre PE-10 tubing. Cavernous tissues from mice, rats or patients with psychogenic erectile dysfunction were stained for factor VIII, alpha-actin and Masson trichrome. Electrical stimulation of the cavernous nerve in mice produced voltage-dependent erectile responses of up to 5 V, with the highest response at a frequency of 12 Hz. The maximal intracavernous pressure recorded at this stimulation parameter was comparable with that in rats. A PE-10 catheter was more reliable for measuring systemic arterial pressure in mice than was a 24-gauge angiocatheter, and the values recorded were similar between mice and rats. The content of endothelial cells, smooth muscle cells and collagen was similar between mice and rats. However, the cavernous tissue of both animals contained lesser amounts of smooth muscle cells and greater amounts of collagen than that of humans (p < 0.01). These results suggest that the mouse is a useful and technically feasible model for the study of penile erection and has functional and structural properties similar to those of rats.  相似文献   
66.
Yoo TH  Li JJ  Kim JJ  Jung DS  Kwak SJ  Ryu DR  Choi HY  Kim JS  Kim HJ  Han SH  Lee JE  Han DS  Kang SW 《Kidney international》2007,71(10):1019-1027
The autocrine and paracrine activation of the renin-angiotensin system (RAS) within cells of the kidney plays a role in the overall pathophysiology of the renal disease due to diabetes. In this study, we focus on components of the RAS in the podocyte as these cells are important in the pathogenesis of glomerulosclerosis and proteinuria. Immortalized mouse podocytes were exposed to media containing normal glucose (NG) or high glucose (HG) for in vitro studies. In vivo studies utilized kidney tissue obtained from rats treated for 3 months with streptozotocin to induce diabetes. Angiotensinogen (AGT) and the angiotensin II (AII) type 1 receptor mRNA and protein were significantly increased in the podocytes cultured under the high glucose conditions. Both angiotensins I and II levels were significantly higher in cell lysates and the conditioned media of cells grown in high glucose. There were no differences in renin activity, angiotensin-converting enzyme level, or AII type 2 receptor level. Glomerular AGT and AII type 1 receptor assessed by means of immunohistochemistry were increased in diabetic rats compared with the control rats. Other measured components of the RAS within the glomeruli were not different. We suggest that increased AGT, an attendant increase in AII and increased AII type 1 receptor in podocytes experiencing diabetic conditions play an important role in the pathogenesis of diabetic nephropathy.  相似文献   
67.
68.
Quadricuspid aortic valve (QAV) is a rare congenital aortic valve anomaly. We present two cases of QAV diagnosed by using echocardiography including transesophageal echocardiography (TEE) and cardiac computed tomography (CT). The first case, QAV with four equal-sized cusps, was identified in a 58-year-old man. The second case, QAV with a small accessory cusp between the right coronary and non-coronary cusp, was identified in a 42-year-old man. TEE and cardiac CT could lead to accurate diagnosis of QAV. QAV in these two patients could be diagnosed before indication for surgery but it is necessary to continue careful follow-up.  相似文献   
69.
Upper extremity deep vein thrombosis (UEDVT) is an infrequent but dangerous vascular event, especially for patients undergoing thoracic surgery. However, there is no standard perioperative management to reduce the risk of pulmonary thromboembolism in such patients. We describe how we performed successful esophagectomy in a patient with UEDVT treated by placing a filter in the superior vena cava during surgery.  相似文献   
70.
The aim of this study was to elucidate whether fecoflowmetry (FFM) could evaluate more detailed evacuative function than anorectal manometry by comparing between FFM or anorectal manometric findings and the clinical questionnaires and the types of surgical procedure in the patients who received anal-preserving surgery. Fifty-three patients who underwent anal-preserving surgery for low rectal cancer were enrolled. The relationships between FFM or the manometric findings and the clinical questionnaires and the types of procedure of anal-preserving surgery were evaluated. There were significant differences between FFM markers and the clinical questionnaire and the types of the surgical procedure, whereas no significant relationship was observed between the manometric findings and the clinical questionnaire and the types of the surgical procedure. FFM might be feasible and useful for the objective assessment of evacuative function and may be superior to manometry for patients undergoing anal-preserving surgery.Key words: Anorectal manometry, Anal-preserving surgery, Fecoflowmetry, Incontinence, Rectal cancerSphincter preservation has been one of the key issues of rectal cancer surgery. Low anterior resection (LAR)1 and internal and external sphincter resection (ISR and ESR) are anal-preserving surgeries.2,3 The aim of these procedures is to restore the normal process of defecation, along with its function, and to improve the quality of life of patients by avoiding permanent colostomy. However, anal-preserving surgery is often associated with evacuative dysfunction and various degrees of incontinence.47Most studies that have assessed the evacuation function have used clinical questionnaires, which are subjective and may vary according to the patient perception.7 There are many factors that can affect the evacuative function, such as the stool consistency, rectal capacity, anal sphincters, pelvic floor muscles, and intra-abdominal pressure. Although manometry with or without the clinical score has also commonly been used, fecoflowmetry (FFM) has been reported to be more accurate and useful for assessing the postoperative anorectal motor function.813 FFM was first introduced by Shafik and is a dynamic method for examining the anorectal motor activity that simulates the natural act of defecation.14 Some studies have shown its usefulness in postoperative patients with anorectal disease,811 but only a few studies have been performed to examine the evacuative function following anal-preserving surgery.12,13 The aim of this study was to evaluate the evacuative function in the postoperative period following anal-preserving surgery in patients with low rectal cancer using FFM, and to compare the results with the Wexner score and anorectal manometry.15  相似文献   
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