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Objective For breast US interpretation, to assess impact of computer-aided diagnosis (CADx) in original mode or with improved sensitivity or specificity. Methods In this IRB approved protocol, orthogonal-paired US images of 319 lesions identified on screening, including 88 (27.6%) cancers (median 7 mm, range 1–34 mm), were reviewed by 9 breast imaging radiologists. Each observer provided BI-RADS assessments (2, 3, 4A, 4B, 4C, 5) before and after CADx in a mode-balanced design: mode 1, original CADx (outputs benign, probably benign, suspicious, or malignant); mode 2, artificially-high-sensitivity CADx (benign or malignant); and mode 3, artificially-high-specificity CADx (benign or malignant). Area under the receiver operating characteristic curve (AUC) was estimated under each modality and for standalone CADx outputs. Multi-reader analysis accounted for inter-reader variability and correlation between same-lesion assessments. Results AUC of standalone CADx was 0.77 (95% CI: 0.72–0.83). For mode 1, average reader AUC was 0.82 (range 0.76–0.84) without CADx and not significantly changed with CADx. In high-sensitivity mode, all observers’ AUCs increased: average AUC 0.83 (range 0.78–0.86) before CADx increased to 0.88 (range 0.84–0.90), P < 0.001. In high-specificity mode, all observers’ AUCs increased: average AUC 0.82 (range 0.76–0.84) before CADx increased to 0.89 (range 0.87–0.92), P < 0.0001. Radiologists responded more frequently to malignant CADx cues in high-specificity mode (42.7% vs 23.2% mode 1, and 27.0% mode 2, P = 0.008). Conclusion Original CADx did not substantially impact radiologists’ interpretations. Radiologists showed improved performance and were more responsive when CADx produced fewer false-positive malignant cues.

Giant encephalocele is an uncommon congenital anomaly with very few published reports available in the English literature. Tetralogy of Fallot associated with situs inversus is also infrequently reported. To our knowledge there are no published reports of an association between giant encephalocele and Tetralogy of Fallot. The additional finding of situs inversus results in a rare pathologic triad, not heretofore described.

Vestibular influences on outflow from the spinal cord are largely mediated via spinal interneurons, although few studies have recorded interneuronal activity during labyrinthine stimulation. The present study determined the responses of upper thoracic interneurons of decerebrate cats to electrical stimulation of the vestibular nerve or natural stimulation of otolith organs and the anterior and posterior semicircular canals using rotations in vertical planes. A majority of thoracic interneurons (74/102) responded to vestibular nerve stimulation at median latencies of 6.5 ms (minimum of approximately 3 ms), suggesting that labyrinthine inputs were relayed to these neurons through trisynaptic and longer pathways. Thoracic interneuronal responses to vertical rotations were similar to those of graviceptors such as otolith organs, and a wide array of tilt directions preferentially activated different cells. Such responses were distinct from those of cells in the cervical and lumbar enlargements, which are mainly elicited by ear-down tilts and are synchronous with stimulus position when low rotational frequencies are delivered, but tend to be in phase with stimulus velocity when high frequencies are employed. The dynamic properties of thoracic interneuronal responses to tilts were instead similar to those of thoracic motoneurons and sympathetic preganglionic neurons. However, the preferred tilt directions of the interneurons were more heterogeneous than thoracic spinal outputs, showing that the outputs do not simply reflect an addition of local interneuronal activity.

Purpose To compare measures of clinical success, such as the need for subsequent intervention and mortality, in patients with left ventricular assist devices (LVADs) undergoing mesenteric angiography for gastrointestinal (GI) bleeding with respect to a control group. Materials and Methods A retrospective study was conducted on 48 consecutive patients undergoing anticoagulation whose GI bleeding was assessed with angiography between August 2007 and June 2014: 24 patients with LVADs and 24 control patients without LVADs. The χ2 and t tests were used for statistical analysis. Results Mean ages were 62.1 years ± 9.6 and 74.5 years ± 11.3 in the LVAD and control groups, respectively. No significant difference was observed in hemodynamic instability, presenting hemoglobin level and International Normalized Ratio, or hemoglobin nadir. Two patients with LVADs (8.3%) and 8 control patients (33.3%) had bleeding detected on angiograms ( P = .032). Six embolizations were performed in patients with LVADs and 8 were performed in control patients. Clinical success was achieved in 2 of 6 patients with LVADs (33.3%) and 7 of 8 control patients (87.5%; P = .036). Seven patients with LVADs (29.2%) and 1 control patient (4.5%) underwent repeat angiography within 14 days ( P = .020). Seven patients with LVADs (29.2%) and 4 control patients (18.2%) required postprocedural endoscopic or operative intervention as definitive therapy ( P = .302). All-cause in-hospital mortality rates were 16.7% in the LVAD group and 4.2% in the control group ( P = .032), and the respective all-cause 1-year mortality rates were 33.3% and 9.1% ( P = .080). Conclusions A higher rate of clinical failure is observed in patients with LVADs presenting with GI bleeding compared with those without LVADs, with a more frequent need for subsequent endoscopic or surgical intervention.

There are several artifacts unique to PET/CT imaging, with CT-based attenuation correction (AC) artifacts being among the most commonly reported. AC artifacts from calcified lymph nodes represent clinically significant and easily misinterpreted PET/CT artifacts that have received little attention in the literature. In this case series, we report three cases of calcified lymph nodes causing an AC artifact and one case of a highly calcified lymph node without an AC artifact. All three cases of calcified lymph nodes causing an AC artifact would have resulted in a change in patient staging, and likely management, if the nodes had been misinterpreted as malignant nodes. In PET/CT imaging, this artifact needs to be considered as a potential cause of apparent FDG activity when calcified lymph nodes are present on the CT portion of a PET/CT study in order to avoid misinterpretation and potential patient mismanagement.

This article educates the reader on idiopathic retroperitoneal fibrosis and emphasizes the importance of considering conditions that mimic this disease on PET/CT through an illustrative case of a 58 year-old man presenting with intermittent abdominal, back, and scrotal pain undergoing successive PET/CT scans, both for diagnosis and following treatment.

There are several artifacts encountered in positron emission tomography/computed tomographic (PET/CT) imaging, including attenuation correction (AC) artifacts associated with using CT for AC. Several artifacts can mimic a 2-deoxy-2-[18F] fluoro-d-glucose (FDG) avid malignant lesions and therefore recognition of these artifacts is clinically relevant. Our goal was to identify and characterize these artifacts and also discuss some protocol variables that may affect image quality in PET/CT.