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1.
Rowan T. Chlebowski MD PhD Juhua Luo PhD Garnet L. Anderson PhD Wendy Barrington PhD Kerryn Reding PhD Michael S. Simon MD JoAnn E. Manson MD DrPh Thomas E. Rohan MBBS PhD Jean Wactawski-Wende PhD Dorothy Lane MD Howard Strickler MD Yasmin Mosaver-Rahmani PhD Jo L. Freudenheim PhD Nazmus Saquib MBBS PhD Marcia L. Stefanick PhD 《Cancer》2019,125(2):205-212
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Michael J. Klingler Stephen K. Babitz Alexander Kutikov Riccardo Campi Georgios Hatzichristodoulou Francesco Sanguedolce Sabine Brookman-May Bulent Akdogan Umberto Capitanio Marco Roscigno Alessandro Volpe Martin Marszalek Robert G. Uzzo Alessandro Antonelli Johan Langenhuijsen Marco Carini Andrea Minervini Brian R. Lane 《Urologic oncology》2019,37(1):33-39
Purpose
Partial nephrectomy (PN) is standard for small renal masses, improving renal function by preserving renal parenchyma compared with radical nephrectomy. Recent work demonstrated that postoperative surgeon assessment of volume preservation (SAVP) and 3D imaging measurements agree and correlate with postoperative function. We hypothesize preoperative assessment of volume preservation (PAVP) with PN based on preoperative imaging will reliably indicate postoperative renal function.Materials and Methods
Data were collected from 336 patients undergoing PN for suspected renal cancer by 40 surgeons at 12 centers in Europe and the United States within the Surface-Intermediate-Base International Consortium. Surgeons recorded PAVP and SAVP for individual patients; pre- and postoperative glomerular filtration rate (GFR) was estimated by Chronic Kidney Disease Epidemiology Collaboration equations. Correlations between PAVP, SAVP, and postoperative GFR were assessed with linear regression models. Bland–Altman analysis was used to assess agreement between PAVP and SAVP with a significant cutoff of 5%.Results
Median PAVP was 90% (interquartile range [IQR] 85%–100%) and SAVP was 90% (IQR: 80%–94%). PAVP and SAVP were moderately correlated (R2?=?0.67, P < 0.0001) and deemed “interchangeable” by Bland–Altman analysis at a 5% acceptable rate of difference (95% CI: ?5.4, ?3.1). Median postoperative GFR was 77.3 (IQR: 56.2, 92.0). Both PAVP (R2?=?0.82, P < 0.0001) and SAVP (R2?=?0.83, P < 0.0001) were correlated with postoperative GFR. Multivariable models utilizing volume-adjusted GFR based on PAVP or SAVP significantly and similarly predicted postoperative GFR (R2?=?0.72 for each).Conclusion
Renal function is closely linked to the amount of parenchymal volume preservation, whether estimated prior to surgery (PAVP) or afterward (SAVP). PAVP provides reasonably accurate information for decision-making in patients considering PN. 相似文献4.
BACKGROUND AND PURPOSE:Although multishot EPI (readout-segmented EPI) has been touted as a robust DWI sequence for cholesteatoma evaluation, its efficacy in disease detection compared with a non-EPI (eg, HASTE) technique is unknown. This study sought to compare the accuracy of readout-segmented EPI with that of HASTE DWI in cholesteatoma detection.MATERIALS AND METHODS:A retrospective review was completed of consecutive patients who underwent MR imaging for the evaluation of suspected primary or recurrent/residual cholesteatomas. Included patients had MR imaging examinations that included both HASTE and readout-segmented EPI sequences and confirmed cholesteatomas on a subsequent operation. Two neuroradiologist reviewers assessed all images, with discrepancies resolved by consensus. The ratio of signal intensity between the cerebellum and any observed lesion was noted.RESULTS:Of 23 included patients, 12 (52.2%) were women (average age, 47.8 [SD, 25.2] years). All patients had surgically confirmed cholesteatomas: Six (26.1%) were primary and 17 (73.9%) were recidivistic. HASTE images correctly identified cholesteatomas in 100.0% of patients. On readout-segmented EPI sequences, 16 (69.6%) were positive, 5 (21.7%) were equivocal, and 2 (8.7%) were falsely negative. Excellent interobserver agreement was noted between reviews on both HASTE (κ = 1.0) and readout-segmented EPI (κ = 0.9) sequences. The average signal intensity ratio was significantly higher on HASTE than in readout-segmented EPI, facilitating enhanced detection (mean difference 0.5; 95% CI, 0.3–0.8; P = .003).CONCLUSIONS:HASTE outperforms readout-segmented EPI in the detection of primary cholesteatoma and disease recidivism.Middle ear cholesteatomas are ectopic, keratinizing squamous epithelium, which may be acquired or, much less commonly, congenital.1,2 Although not considered a true neoplasm, cholesteatomas are locally destructive and have a high propensity for recurrence following surgical removal. As they gradually expand, cholesteatomas erode the osseous structures within and adjacent to the middle ear cavity, including the ossicles, labyrinth, fallopian canal, and middle fossa bone plate.3 Current mainstay therapy includes microsurgical extirpation, with the chief goal of complete disease removal and prevention of intratemporal and intracranial complications.4 The most common microsurgical approach for cholesteatoma is an canal wall up tympanomastoidectomy, in which the posterior bony ear canal is left intact and the tympanic membrane is reconstructed. Depending on the extent of disease at surgery, a planned second-look procedure may be performed approximately 1 year after the initial operation to evaluate residual disease and potentially reconstruct the ossicular chain when indicated. Nevertheless, residual and/or recurrent (ie, recidivism) disease occurs in up to 30% of cases. Imaging is crucial in cholesteatoma management; it aids in the initial diagnosis and may obviate the need for second-look surgery.5,6During the past decade, DWI has emerged as a powerful diagnostic tool for detection of both primary and residual or recurrent cholesteatomas.7-9 Cholesteatomas demonstrate marked hyperintensity on DWI , likely related to either T2 shinethrough or intralesional restricted diffusion related to keratin debris.10 Across the years, there have been many iterations of DWI optimization for cholesteatoma identification. The EPI trajectory used by conventional DWI makes such sequences prone to substantial susceptibility artifacts, and single-shot EPI sequences were found to be poor at identifying lesions of <4–5 mm.11-13 Consequently, non-EPI DWI techniques began to be favored; such algorithms minimize susceptibility artifacts and geometric distortion related to the skull base and are able to detect lesions as small as 2 mm.14,15 BLADE (Siemens) and other such PROPELLER sequences are subtypes of non-EPI techniques that minimize susceptibility artifacts and geometric distortions by sampling k-space in a rotating fashion.16,17More recently, HASTE DWI (Siemens) has emerged as a particularly effective sequence, which is relatively insensitive to motion and has been shown in prior studies to detect cholesteatomas with promising accuracy.18,19 Although traditional EPI techniques have been largely abandoned in the setting of cholesteatoma detection, readout-segmented EPI (RESOLVE; Siemens) DWI is a relatively new technique that has been promoted as a possible alternative diffusion sequence. RESOLVE is a multishot (MS) EPI sequence that is able to reduce geometric distortions at the expense of longer imaging time. Recent reports have indicated that RESOLVE may be a useful sequence in cases of suspected cholesteatoma.7,20Despite its proposed efficacy in cholesteatoma imaging, the diagnostic utility of RESOLVE sequences has yet to be robustly evaluated against non-EPI DWI, the current criterion standard. Thus, this study was conceived with the chief goal of assessing the accuracy of RESOLVE in the detection of cholesteatomas and comparing the ability of RESOLVE with that of HASTE sequences in this context. 相似文献
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Lane Thaut Wells Weymouth Branden Hunsaker Daniel Reschke 《The Journal of emergency medicine》2019,56(1):23-28
Background
Central vein catheter (CVC) placement using the modified Seldinger technique is a common procedure in the emergency department, but can be time consuming due to the multiple pieces of equipment included in central line kits and the number of steps in the procedure. Preassembled devices combine a needle, guidewire, dilator, and sheath into one unit and potentially simplify the process and reduce time required for CVC placement using the accelerated Seldinger technique.Objective
Our aim was to evaluate whether the use of combination central line devices and the accelerated Seldinger technique will reduce the time required to place a CVC and increase the ease of the procedure.Methods
This two-arm randomized crossover study comparing the accelerated Seldinger technique to the modified Seldinger technique was performed in a simulation setting. Subjects were selected from among emergency physicians, emergency medicine residents, interns, physician assistants, and medical students. Subjects were timed using the modified and accelerated Seldinger techniques. Ease of use and satisfaction data were collected after both procedures.Results
The use of the accelerated Seldinger technique with a combination CVC device was significantly faster compared to the modified Seldinger technique with a standard CVC kit. Procedure time was reduced by 35% (p = 0.001), and ease of use was increased by 7% (p = 0.046), without any increase in errors.Conclusions
In the simulated setting, the accelerated Seldinger technique using combination CVC devices is a faster and easier method for CVC placement compared to the modified Seldinger technique. 相似文献8.
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