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101.
El-Ghar ME Shokeir AA El-Diasty TA Refaie HF Gad HM El-Dein AB 《The Journal of urology》2004,172(3):985-988
PURPOSE: We evaluated contrast enhanced spiral computerized tomography (CT) as a single session for the anatomical and functional assessment of patients with chronic obstructive uropathy and normal serum creatinine. MATERIALS AND METHODS: The study included 65 patients with unilateral or bilateral chronic renal obstruction and normal serum creatinine. Five patients had bilateral obstruction and the remaining 60 had unilateral obstruction and a normal contralateral kidney. Therefore, the total number of renal units was 130, that is 70 obstructed and 60 normal. All patients underwent contrast enhanced spiral CT together with excretory urography (IVP) and Tc-mercaptoacetyltriglycine renal scan. CT was used to identify the cause of obstruction and selectively determine the glomerular filtration rate (GFR) of the 2 kidneys. The diagnostic accuracy of CT for identifying the cause of hydronephrosis was compared with that of IVP. Moreover, a correlation was made between CT GFR and isotope GFR. RESULTS: Obstruction was caused by ureteropelvic junction narrowing in 25 cases, ureteral stones in 21, ureteral stricture in 20 and extrinsic ureteral obstruction in 4. Contrast enhanced spiral CT identified the cause of hydronephrosis in all obstructed kidneys (100% sensitivity), while IVP identified the cause in 52 (74% sensitivity), which was a significant difference (p <0.05). CT and IVP excluded obstruction in all normal kidneys (100% specificity). A comparison between the isotope GFR of obstructed kidneys with the corresponding CT GFR showed a perfect correlation (r = 0.78, p <0.0001). Moreover, a similar comparison between isotope GFR and CT GFR of normal kidneys showed an excellent correlation (r = 0.73, p <0.0001). In obstructed and normal kidneys mean isotope clearance was not significantly different from that of mean CT clearance. CONCLUSIONS: Contrast enhanced spiral CT is more sensitive than IVP for identifying the cause of chronic obstructive uropathy. Moreover, it is as accurate as radioisotope renal scan for calculating the total and separate kidney function. We recommend spiral CT with contrast medium as a single radiological diagnostic modality for the assessment of patients with chronic renal obstruction and normal serum creatinine. 相似文献
102.
Mekhail TM Kawanishi-Tabata R Tubbs R Novick A Elson P Ganapathi R Ganapathi M Bukowski R 《Urologic oncology》2003,21(6):424-430
Limited information is available on the correlation of telomerase activity and the clinical and pathological characteristics, in patients with renal cell carcinoma (RCC). Telomerase repeat amplification protocol (TRAP) was used to measure telomerase activity in frozen RCC specimens from partial/radical nephrectomies performed between 1987 and 1991. Presence of tumor tissue was verified by a pathologist using hematoxylin and eosin stained sections. RNA was measured to ensure the presence of intact protein necessary for telomerase expression. Data on demographics, tumor type, and stage at presentation, local recurrence, distant metastasis, disease-free survival (DFS), and overall survival (OS) was collected, and telomerase activity was correlated with each of these variables. Forty-nine of 67 patients (73%) were telomerase positive (+ve). Gender and stage were the only variables that appeared to be associated with telomerase positivity. Tumors were telomerase +ve in 12/21 females (57 %) vs. 37/46 males (80%) (P = 0.07). Tumors were telomerase +ve in 85% of Stage IV, 76% of Stage III, and 70% of Stage I/II patients (P = 0.12). Five-year survival was 0% for Stage IV, 57% for Stage III, and 77% for Stage I/II patients (P < 0.001), DFS 54% for stage III and 84% for Stage I/II patients (P = 0.05). Telomerase activity, however, was not related to survival in either univariate or multivariate analysis. In patients with telomerase +ve tumors 5-year survival was 55%, and with telomerase −ve tumors 58% (P = 0.56). Stage was the only variable associated with OS or DFS in clear cell RCC patients. In patients with advanced disease, there is a high incidence of telomerase positivity was found, within this limited sample, however, no correlation with survival was found. 相似文献
103.
Tarek Alhamad Michelle Lubetzky Krista L. Lentine Emmanuel Edusei Ronald Parsons Martha Pavlakis Kenneth J. Woodside Deborah Adey Christopher D. Blosser Beatrice P. Concepcion John Friedewald Alexander Wiseman Neeraj Singh Su-Hsin Chang Gaurav Gupta Miklos Z. Molnar Arpita Basu Edward Kraus Song Ong Arman Faravardeh Ekamol Tantisattamo Leonardo Riella Jim Rice Darshana M. Dadhania 《American journal of transplantation》2021,21(9):3034-3042
Kidney allograft failure and return to dialysis carry a high risk of morbidity. A practice survey was developed by the AST Kidney Pancreas Community of Practice workgroup and distributed electronically to the AST members. There were 104 respondents who represented 92 kidney transplant centers. Most survey respondents were transplant nephrologists at academic centers. The most common approach to immunosuppression management was to withdraw the antimetabolite first (73%), while only 12% responded they would withdraw calcineurin inhibitor (CNI) first. More than 60% reported that the availability of a living donor is the most important factor in their decision to taper immunosuppression, followed by risk of infection, risk of sensitization, frailty, and side effects of medications. More than half of respondents reported that embolization was either not available or offered to less than 10% as an option for surgical intervention. Majority reported that ≤50% of failed allograft patients were re-listed before dialysis, and less than a quarter of transplant nephrologists performed frequent visits with their patients with failed kidney allograft after they return to dialysis. This survey demonstrates heterogeneity in the care of patients with a failing allograft and the need for more evidence to guide improvements in clinical practice related to transition of care. 相似文献
104.
105.
Mohamed Abdel Wahab Ahmed Shehta Mohamed Elshoubary Tarek Salah Omar Fathy Ahmed Sultan Ahmed Nabieh Elghawalby Mahmoud Ali Amr Mohamed Yassen Mohamed Elmorshedi Mohamed Eldesoky Ahmed Monier Rami Said 《Journal of gastrointestinal surgery》2018,22(12):2055-2063
Background
Portal vein thrombosis (PVT) is a common complication for patients with end-stage liver disease. The presence of PVT used to be a contraindication to living donor liver transplantation (LDLT). The aim of this study is to evaluate the influence of preoperative PVT on perioperative and long-term outcomes of the recipients after LDLT.Methods
We reviewed the data of patients who underwent LDLT during the period between 2004 till 2017.Results
During the study period, 500 cases underwent LDLT. Patients were divided into three groups. Group I included non-PVT, 446 patients (89.2%); group II included attenuated PV, 26 patients (5.2%); and group III included PVT, 28 patients (5.6%). Higher incidence of hematemesis and encephalopathy was detected in PVT (p?=?0.001). Longer anhepatic phase was found in PVT (p?=?0.013). There were no significant differences between regarding operation time, blood loss, transfusion requirements, ICU, and hospital stay. The 1-, 3-, and 5-year overall survival (OS) rates of non-PVT were 80.5%, 77.7%, and 75%, and for attenuated PV were 84.6%, 79.6%, and 73.5%, and for PVT were 88.3%, 64.4%, and 64.4%, respectively. There was no significant difference between the groups regarding OS rates (logrank 0.793).Conclusion
Preoperative PVT increases the complexity of LDLT operation, but it does not reduce the OS rates of such patients.106.
107.
Ahmed Hafez Afifi Tarek Abdel Samie Abdel Maksoud Khaled Ibrahim EL-noueam Mohamed A. Ataa Dina Mohamad Abdallah 《The Egyptian Journal of Radiology and Nuclear Medicine》2017,48(2):493-507
Objectives
To evaluate role of multiparametric-MRI as comprehensive technique for determining local staging of UB cancer and predicting histological grading of lymphadenopathy.Materials and methods
Fifty patients diagnosed as cancer bladder prospectively included and mp-MRI data were interpreted. Multiparametric techniques included added role of high resolution T2 weighted images (HR T2WI), diffusion weighted MRI (DW-MRI) and dynamic contrast enhanced MRI (DCE-MRI). Accuracy of these techniques separately and in conjunction were evaluated using histopathological findings as reference gold standard. Diagnosis of bladder cancer was performed either clinically, through urine cytology or using other radiologic investigations including ultrasonography or computed tomography.Results
Histopathological confirmation for local T staging done in 40 patients (80%) using cystoscopy/biopsy or from transurethral resection of bladder tumors (TURT) and in 10 patients (20%) from radical cystectomy. Metastatic lymphadenopathy was histopatholgically proved after radical cystectomy in 5 patients (10%), of them 3 were stage N1 and 2 were stage N2. Diagnostic accuracy of mp-MRI (88%) was superior to DW-MRI (82%), DCE-MRI (74%) and high resolution T2W-MRI (52%) in differentiating non-muscle invasive from muscle invasive and in differentiating organ-confined from non organ-confined tumors respectively. The agreement between the mp-MRI and histopathological staging were greater than DW-MRI (κ = 0.679), DCE-MRI (κ = 0.566) and high resolution T2W-MRI (κ = 0.274). Over staging decreased from (48%) using high resolution T2W or (26%) using DCE-MRI, or (18%) using DW to (12%) using multiparametric-MRI. Low ADC values and time-intensity curve were compared with histological grades and showed significant correlation. Size criteria of the lymph nodes, their restriction and low ADC values in DW-MRI suggest their metastatic nature.Conclusion
Mp-MRI is comprehensive & effective tool for determining local T stages, and the histological grades of urinary bladder cancers. Also, it predicts nature & stages of local lymph nodes, exhibiting high diagnostic performance with excellent objectivity. 相似文献108.
109.
Paolo Preziosa Maria A. Rocca Elisabetta Pagani Maria Laura Stromillo Christian Enzinger Antonio Gallo Hanneke E. Hulst Matteo Atzori Deborah Pareto Gianna C. Riccitelli Massimiliano Copetti Nicola De Stefano Franz Fazekas Alvino Bisecco Frederik Barkhof Tarek A. Yousry Maria J. Arévalo Massimo Filippi and the MAGNIMS Study Group 《Human brain mapping》2016,37(4):1627-1644
In a multicenter setting, we applied voxel‐based methods to different structural MR imaging modalities to define the relative contributions of focal lesions, normal‐appearing white matter (NAWM), and gray matter (GM) damage and their regional distribution to cognitive deficits as well as impairment of specific cognitive domains in multiple sclerosis (MS) patients. Approval of the institutional review boards was obtained, together with written informed consent from all participants. Standardized neuropsychological assessment and conventional, diffusion tensor and volumetric brain MRI sequences were collected from 61 relapsing‐remitting MS patients and 61 healthy controls (HC) from seven centers. Patients with ≥2 abnormal tests were considered cognitively impaired (CI). The distribution of focal lesions, GM and WM atrophy, and microstructural WM damage were assessed using voxel‐wise approaches. A random forest analysis identified the best imaging predictors of global cognitive impairment and deficits of specific cognitive domains. Twenty‐three (38%) MS patients were CI. Compared with cognitively preserved (CP), CI MS patients had GM atrophy of the left thalamus, right hippocampus and parietal regions. They also showed atrophy of several WM tracts, mainly located in posterior brain regions and widespread WM diffusivity abnormalities. WM diffusivity abnormalities in cognitive‐relevant WM tracts followed by atrophy of cognitive‐relevant GM regions explained global cognitive impairment. Variable patterns of NAWM and GM damage were associated with deficits in selected cognitive domains. Structural, multiparametric, voxel‐wise MRI approaches are feasible in a multicenter setting. The combination of different imaging modalities is needed to assess and monitor cognitive impairment in MS. Hum Brain Mapp 37:1627‐1644, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
110.
Sarah Finlayson MBChB DPhil Jasper M. Morrow FRACP Pedro M. Rodriguez Cruz MD MSc Christopher D.J. Sinclair PhD Arne Fischmann PD DrMed John S. Thornton PhD Steve Knight BSc Ray Norbury PhD Mel White BSc Michal Al‐hajjar MD Nicola Carboni MD PhD Sandeep Jayawant MD FRCPCh Stephanie A. Robb MD Tarek A. Yousry DrMed Habil FRCR David Beeson PhD Jacqueline Palace DM 《Muscle & nerve》2016,54(2):211-219