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Young Bennetsen posted an update 2 days, 16 hours ago
ltaneous assessment of left and right ventricular volumes during continuous exercise. Intra- and inter-observer reproducibility were excellent. Inter-scan LV and RV ejection fraction were also highly reproducible.
Simultaneous magnetic resonance (MR) acoustic radiation force imaging (ARFI) and MR thermometry (MRT) (STARFI) based on coherent echo-shifted (cES) sequence was proposed and comprehensively compared to radiofrequency (RF)-spoiled gradient echo (spGRE) STARFI.
Through use of delicately designed gradients, a collection of echoes was delayed by one repetition time (TR) cycle. The crusher gradient after readout (RO) was used as the displacement encoding gradient (DEG). The sequence was intrinsically sensitive to temperature. High-intensity focused ultrasound (HIFU) pulses were interleaved ON/OFF in successive TRs to separate the phase changes induced by displacement due to acoustic radiation force (ARF) impulses and temperature. Bloch simulation was performed to study the phase sensitivity to displacement of the proposed cES STARFI and spGRE STARFI. The proposed cES sequence was evaluated and compared to spGRE STARFI in
porcine muscle and
porcine brain.
The minimally achievable TR of cES STARFI was shSTARFI sequence can provide simultaneous MR-ARFI and temperature measurements during pulsed HIFU applications. Though the exact displacement cannot be quantified directly, the sequence showed increased phase sensitivity compared with the spGRE sequence and provided efficient visualization of the focal spot. cES STARFI could therefore be a desirable alternative to spGRE STARFI in practical applications.
The cES STARFI sequence can provide simultaneous MR-ARFI and temperature measurements during pulsed HIFU applications. Though the exact displacement cannot be quantified directly, the sequence showed increased phase sensitivity compared with the spGRE sequence and provided efficient visualization of the focal spot. cES STARFI could therefore be a desirable alternative to spGRE STARFI in practical applications.
To evaluate the clinical utility of combined T2-weighted imaging and T2-mapping for the detection of prostate cancer.
Forty patients underwent multiparametric magnetic resonance imaging (mpMRI) and T2-mapping of the prostate. Three readers each reviewed two sets of images T2-weighted fast spin-echo (FSE) sequence (standard T2), and standard T2 in combination with T2-mapping. Each reader assigned probability scores for malignancy to each zone [peripheral zone (PZ) or transition zone (TZ)]. Inter-observer variability for standard T2 and combined standard T2 with T2-mapping were assessed. Diagnostic accuracy was compared between standard T2 and combined standard T2 with T2-mapping.
There was fair agreement between all three readers for standard T2 [intraclass correlation coefficient (ICC) =0.56] and combined standard T2 with T2-mapping (ICC =0.58). There was no significant difference in the area under the receiver operator characteristics curve for standard T2 compared to combined standard T2 with T2-mapping (0.89
0.82, P=0.31). Sensitivity (Sn) for combined standard T2 with T2-mapping was significantly higher compared to standard T2 alone (73.0%
49.2%, P=0.006). Specificity (Sp) for combined standard T2 with T2-mapping was borderline significantly lower compared to standard T2 alone (89.3%
94.9%, P=0.05). There was no significant differences between the negative predictive values (NPVs) and positive predictive values (PPVs) (P=0.07, P=0.45).
Combination of T2-weighted imaging and T2-mapping could potentially increase Sn for prostate malignancy compared to T2-weighted imaging alone.
Combination of T2-weighted imaging and T2-mapping could potentially increase Sn for prostate malignancy compared to T2-weighted imaging alone.
The method of locating pulmonary nodules before operation plays a crucial role in the surgery of pulmonary ground-glass nodules (GGNs). However, the methodologies surrounding intraoperative localization remains limited, with the majority procedures requiring specific additional equipment. We report a new approach in locating pulmonary GGNs by image-localized body surface marking intraoperative (IBMI) localization.
A retrospective review of the medical records of 76 patients with pulmonary GGNs was performed. All patients underwent IBMI localization between January 2018 and March 2019. Twenty-six patients underwent CT-guided hook wire localization before IBMI localization during surgery. IBMI localization was undertaken directly without pre-treatment in the remaining patients. The efficacy and complications of this approach were analyzed and compared with other pre- or intraoperative localization methods in the current literature.
The intraoperative localizations were performed successfully in 72 of all 76 patients pulmonary GGNs within a mean duration of 5.3±1.8 (range, 2.0 to 9.6) minutes. check details The GGNs in four cases were found to have a significant deviation (>1.5 cm) from the positioning points. All GGNs were successfully resected. Except for five cases of active chest wall bleeding (6.5%), no other intra- or postoperative complications occurred.
The IBMI localization approach is a safe and short-duration procedure with high success rates and fewer complications. We used it for the first time for intraoperative localization of peripheral GGNs with excellent results.
The IBMI localization approach is a safe and short-duration procedure with high success rates and fewer complications. We used it for the first time for intraoperative localization of peripheral GGNs with excellent results.
The traditional criterion for the diagnosis of implant loosening in total hip arthroplasty (THA) was once defined as a radiolucent line of >2 mm in width, based on plain radiography. Recent progress in imaging technology has allowed for the identification of complete radiolucent lines of ≤2 mm around the whole prosthesis as the basis for diagnosing component loosening in the absence of component migration. This study aimed to compare the sensitivity and specificity of digital tomosynthesis with metal artifact reduction with those of radiography and conventional computed tomography (CT) for detecting radiolucent lines of ≤2 mm surrounding cementless femoral stems of different widths.
The medullary canals of 4 cadaveric femurs were broached to 13 mm in diameter. Cylindrical cementless femoral stems with diameters of 9, 10, 11, 12, and 13 mm were sequentially inserted into each femur, creating 5 groups of radiolucent lines 2.0, 1.5-1.6, 1.1-1.2, 0.5-0.6, and 0 mm in diameter, respectively. Imaging by tomosynthesis, radiography, and CT was conducted for each radiolucent line model.