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91.
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PURPOSE: The incidence of kidney stones in adults has increased in the last 30 years. This retrospective, single site review was done to test the hypotheses that the incidence of urolithiasis in pediatric patients increased from 1994 to 2005, and that metabolic abnormalities were more common in patients with renal stones in the final 3 years of the study period. MATERIALS AND METHODS: Charts from 2 time periods were reviewed, 1994 to 1996 (period 1) and 2003 to 2005 (period 2). Clinical and laboratory data, including demographics, presenting complaints, laboratory assessment, treatment and outcome, were tabulated in patients with confirmed urolithiasis. RESULTS: The number of patients with urolithiasis increased from 7 in period 1 to 61 in period 2. When expressed as cases per 100 new patients the incidence increased 4.6 times (p = 0.014). Focusing on period 2, 28% of patients were younger than 10 years. While blood tests were generally normal, 76% of patients had at least 1 abnormality in the 24-hour urine collection. Hypocitraturia, which was the most common metabolic abnormality, was noted in 52% of patients. The small number of patients in period 1 precluded determination as to whether metabolic abnormalities were more common in period 2. Surgery and/or lithotripsy was required in 12 children. Stone disease recurred in 39% of the patients. CONCLUSIONS: The incidence of urolithiasis in the pediatric population increased nearly 5-fold at our institution during the last decade. We recommend that the primary diagnostic test be a 24-hour urine collection. The most common metabolic abnormality was hypocitraturia, followed by hypercalciuria. Recurrence of stones is common (approximately 40% rate) and followup is advised.  相似文献   
93.
Huang Y  Gloviczki P  Duncan AA  Kalra M  Hoskin TL  Oderich GS  McKusick MA  Bower TC 《Journal of vascular surgery》2008,47(6):1203-1210; discussion 1210-1
OBJECTIVES: To assess expansion rate of common iliac artery aneurysms (CIAAs) and define outcomes after open repair (OR) and endovascular repair (EVAR). METHODS: Clinical data of 438 patients with 715 CIAAs treated between 1986 and 2005 were retrospectively reviewed. Size, presentations, treatments, and outcomes were recorded. Kaplan-Meier method with log-rank tests and chi2 test were used for analysis. RESULTS: Interventions for 715 CIAAs (median, 4 cm; range, 2-13 cm) were done in 512 men (94%) and 26 women (6%); 152 (35%) had unilateral and 286 (65%) had bilateral CIAAs. Group 1 comprised 377 patients (633 CIAAs) with current or previously repaired abdominal aortic aneurysm (AAA). Group 2 comprised 15 patients (24 CIAAs) with associated internal iliac artery aneurysm (IIAA). Group 3 comprised 46 patients (58 isolated CIAAs). Median expansion rate of 104 CIAAs with at least two imaging studies was 0.29 cm/y; hypertension predicted faster expansion (0.32 vs 0.14 cm/y, P = .01). A total of 175 patients (29%) were symptomatic. The CIAA ruptured in 22 patients (5%, median, 6 cm; range, 3.8-8.5 cm), and the associated AAA ruptured in 20 (4%). Six (27%) ilioiliac or iliocaval fistulas developed. Repairs were elective in 396 patients (90%) and emergencies in 42 (10%). OR was performed in 394 patients (90%) and EVAR in 44 (10%). The groups had similar 30-day mortality: 1% for elective, 27% for emergency repairs (P < .001); 4% after OR (elective, 1%; emergency, 26%), and 0% after EVAR. No deaths occurred after OR of arteriovenous fistula. Complications were more frequent and hospitalization was longer after OR than EVAR (P < .05). Mean follow-up was 3.7 years (range, 1 month-17.5 years). The groups had similar 5-year primary (95%) and secondary patency rates (99.6%). At 3 years, secondary patency was 99.6% for OR and 100% for EVAR (P = .66); freedom from reintervention was similar after OR and EVAR (83% vs 69%, P = .17), as were survival rates (76% vs 77%, P = .70). CONCLUSIONS: The expansion rate of CIAAs is 0.29 cm/y, and hypertension predicts faster expansion. Because no rupture of a CIAA <3.8 cm was observed, elective repair of asymptomatic patients with CIAA >or=3.5 cm seems justified. Although buttock claudication after EVAR remains a concern, results at 3 years support EVAR as a first-line treatment for most anatomically suitable patients who require CIAA repair. Patients with compressive symptoms or those with AVF should preferentially be treated with OR.  相似文献   
94.
Between 1986 and 2005, 22 patients (mean age, 14.7 years; range, 3-21) with renal hypertension underwent renal artery revascularization for 28 lesions, 23 with open repair (OR) and 5 with percutaneous transluminal renal angioplasty (PTRA). Thirty-day morbidity was 17% (4/23). Hypertension was cured in 13 (57%), improved in 8 (38%), and unchanged in 1 (5%). Renal function worsened in 1. At a mean follow-up of 4.9 years, 1-year patency rate was 94% and maintained for 5 years. Hypertension at 1 year was cured in 6 of 14 patients (43%; OR, 4; PTRA, 2) and improved in 8 (57%; OR, 7; PTRA, 1); hypertension at 5 years was cured in 50% and improved in 50%. Renal function remained unchanged in all patients who were followed. The authors conclude that both OR and PTRA benefit pediatric patients. PTRA for selected patients may be promising as a first line treatment or as a bridge to definitive OR in children with small arteries.  相似文献   
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Gill  Tania S.  Varghese  Bino A.  Hwang  Darryl H.  Cen  Steven Y.  Aron  Manju  Aron  Monish  Duddalwar  Vinay A. 《Abdominal imaging》2019,44(4):1470-1480
Purpose

The purpose of the study was to evaluate the feasibility of using contrast-enhanced computed tomography (CECT)-based texture analysis (CTTA) metrics to differentiate between juxtatumoral perinephric fat (JPF) surrounding low-grade (ISUP 1–2) versus high-grade (ISUP 3–4) clear cell renal cell carcinoma (ccRCC).

Methods

In this IRB-approved study, we retrospectively queried the surgical database between June 2009 and April 2016 and identified 83 patients with pathologically confirmed ccRCC (low grade: n = 54, mean age = 61.5 years, 18F/35M; high grade n = 30, mean age = 61.7 years, 8F/22M) who also had pre-operative multiphase CT acquisitions. CT images were transferred to a 3D workstation, and nephrographic phase JPF regions were manually segmented. Using an in-house developed Matlab program, a CTTA panel comprising of texture metrics extracted using six different methods, histogram, 2D- and 3D-Gray-level co-occurrence matrix (GLCM) and Gray-level difference matrix (GLDM), and 2D-Fast Fourier Transform (FFT) analyses, was applied to the segmented images to assess JPF textural heterogeneity in low- versus high-grade ccRCC. Univariate analysis and receiver-operator characteristics (ROC) analysis were used to assess interclass differences in texture metrics and their prediction accuracy, respectively.

Results

All methods except GLCM consistently revealed increased heterogeneity in the JPF surrounding high- versus low-grade ccRCC. FFT showed increased complexity index (p < 0.01). Histogram analysis showed increased kurtosis and positive skewness in (p < 0.03), and GLDM analysis showed decreased measure of correlation coefficient (MCC) (p < 0.04). Several of the GLCM metrics showed statistically significant (p < 0.04) textural differences between the two groups, but with no consistent trend. ROC analysis showed that MCC in GLCM analysis had an area under the curve of 0.75.

Conclusions

Our study suggests that CTTA of ccRCC shows statistically significant textural differences in JPF surrounding high- versus low-grade ccRCC.

  相似文献   
98.
Globally, there is increasing emphasis on value-based cancer care. Rising healthcare costs and reduced health care spending and budgets, especially in low- and middle-income countries (LMICs), call for patients, providers, and healthcare systems to apply the Choose Wisely (CW) approach. This approach seeks to advance a dialogue on avoiding unnecessary medical tests, treatments, and procedures. Several factors have been described as barriers and facilitators to the implementation of the Choosing Wisely recommendations in high-income countries but none for LMICs. In this review, we attempt to classify potential barriers to the Choose Wisely implementation relative to the sources of behavior and potential intervention functions that can be implemented in order to reduce these barriers.  相似文献   
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