To determine if behavioral symptoms in patients with primary progressive aphasia (PPA) were associated with degeneration of a ventral frontotemporal network.
We used diffusion tensor imaging ...tractography to quantify abnormalities of the uncinate fasciculus that connects the anterior temporal lobe and the ventrolateral frontal cortex. Two additional ventral tracts were studied: the inferior fronto-occipital fasciculus and the inferior longitudinal fasciculus. We also measured cortical thickness of anterior temporal and orbitofrontal regions interconnected by these tracts. Thirty-three patients with PPA and 26 healthy controls were recruited.
In keeping with the PPA diagnosis, behavioral symptoms were distinctly less prominent than the language deficits. Although all 3 tracts had structural pathology as determined by tractography, significant correlations with scores on the Frontal Behavioral Inventory were found only for the uncinate fasciculus. Cortical atrophy of the orbitofrontal and anterior temporal lobe cortex was also correlated with these scores.
Our findings indicate that damage to a frontotemporal network mediated by the uncinate fasciculus may underlie the emergence of behavioral symptoms in patients with PPA.
The purpose of this study was to report fetal cases of subaortic and retroesophageal anomalous courses of the left brachiocephalic vein (LBCV) evaluated by fetal cardiac magnetic resonance imaging ...(MRI). A retrospective review of 7282 fetal cardiac MRI from June 2006 to March 2017, nine cases of anomalous courses of the LBCV were correctly diagnosed by fetal cardiac MRI, one case of abnormal subaortic left brachiocephalic vein (ASLBV) missed by fetal MRI was identified postnatally during further imaging of the TOF. The diagnosis was confirmed postnatally by cardiac CT/MRI. An ASLBV was found in 8 cases, a retroesophageal LBCV was found in 2 additional cases with right aortic arch and aberrant left subclavian artery. 3 of 8 ASLBV cases were with a right aortic arch, 4 ASLBV cases had additional cardiovascular anomalies with one case isolated. 7 of 8 ASLBV and 2 retroesophageal LBCV were correctly diagnosed by fetal cardiac MRI; however fetal cardiac MRI missed 2 cases of associated pulmonary atresia (PA). Prenatal echocardiography (echo) correctly diagnosed five ASLBV and one retroesophageal LBCV as well as associated intracardiac anomalies. Fetal cardiac MRI can be a useful adjunct in the identification of subaortic and retroesophageal anomalous courses of the LBCV prenatally.
When extreme, anxiety-a state of distress and arousal prototypically evoked by uncertain danger-can be debilitating. Uncertain anticipation is a shared feature of situations that elicit signs and ...symptoms of anxiety across psychiatric disorders, species, and assays. Despite the profound significance of anxiety for human health and wellbeing, the neurobiology of uncertain-threat anticipation remains unsettled. Leveraging a paradigm adapted from animal research and optimized for fMRI signal decomposition, we examined the neural circuits engaged during the anticipation of temporally uncertain and certain threat in 99 men and women. Results revealed that the neural systems recruited by uncertain and certain threat anticipation are anatomically colocalized in frontocortical regions, extended amygdala, and periaqueductal gray. Comparison of the threat conditions demonstrated that this circuitry can be fractionated, with frontocortical regions showing relatively stronger engagement during the anticipation of uncertain threat, and the extended amygdala showing the reverse pattern. Although there is widespread agreement that the bed nucleus of the stria terminalis and dorsal amygdala-the two major subdivisions of the extended amygdala-play a critical role in orchestrating adaptive responses to potential danger, their precise contributions to human anxiety have remained contentious. Follow-up analyses demonstrated that these regions show statistically indistinguishable responses to temporally uncertain and certain threat anticipation. These observations provide a framework for conceptualizing anxiety and fear, for understanding the functional neuroanatomy of threat anticipation in humans, and for accelerating the development of more effective intervention strategies for pathological anxiety.
Anxiety-an emotion prototypically associated with the anticipation of uncertain harm-has profound significance for public health, yet the underlying neurobiology remains unclear. Leveraging a novel neuroimaging paradigm in a relatively large sample, we identify a core circuit responsive to both uncertain and certain threat anticipation, and show that this circuitry can be fractionated into subdivisions with a bias for one kind of threat or the other. The extended amygdala occupies center stage in neuropsychiatric models of anxiety, but its functional architecture has remained contentious. Here we demonstrate that its major subdivisions show statistically indistinguishable responses to temporally uncertain and certain threat. Collectively, these observations indicate the need to revise how we think about the neurobiology of anxiety and fear.
Purpose The purpose of this study was to investigate the relation of the Segond fracture with the anterolateral ligament (ALL) of the knee. Methods To identify the soft-tissue structure causative for ...the Segond fracture, a study was set up to compare anatomic details of the tibial insertion of the recently characterized ALL in cadaveric knees (n = 30) with radiologic data obtained from patients (n = 29) with a possible Segond fracture based on an imaging protocol search. The spatial relation of the ALL footprint with well-identifiable anatomic landmarks at the lateral aspect of the knee was determined, and this was repeated for the Segond fracture bed. Results In all of the included cadaveric knees, a well-defined ALL was found as a distinct ligamentous structure connecting the lateral femoral epicondyle with the anterolateral proximal tibia. The mean distance of the center of the tibial ALL footprint to the center of the Gerdy tubercle (GT-ALL distance) measured 22.0 ± 4.0 mm. The imaging database search identified 26 patients diagnosed with a Segond fracture. The mean GT-Segond distance measured 22.4 ± 2.6 mm. The observed difference of 0.4 mm (95% confidence interval, –1.5 to 2.2 mm) between the GT-ALL distance and GT-Segond distance was neither statistically significant ( P = .70) nor clinically relevant. Conclusions The results of this study confirmed the hypothesis that the ALL inserts in the region on the proximal tibia from where Segond fractures consistently avulse, thus suggesting that the Segond fracture is actually a bony avulsion of the ALL. Clinical Relevance Although the Segond fracture remains a useful radiographic clue for indirect detection of anterior cruciate ligament injuries, the Segond fracture should be considered a frank ligamentous avulsion itself.
To define a prostate fossa clinical target volume (PF-CTV) for Radiation Therapy Oncology Group (RTOG) trials using postoperative radiotherapy for prostate cancer.
An RTOG-sponsored meeting was held ...to define an appropriate PF-CTV after radical prostatectomy. Data were presented describing radiographic failure patterns after surgery. Target volumes used in previous trials were reviewed. Using contours independently submitted by 13 radiation oncologists, a statistical imputation method derived a preliminary "consensus" PF-CTV.
Starting from the model-derived CTV, consensus was reached for a CT image-based PF-CTV. The PF-CTV should extend superiorly from the level of the caudal vas deferens remnant to >8-12 mm inferior to vesicourethral anastomosis (VUA). Below the superior border of the pubic symphysis, the anterior border extends to the posterior aspect of the pubis and posteriorly to the rectum, where it may be concave at the level of the VUA. At this level, the lateral border extends to the levator ani. Above the pubic symphysis, the anterior border should encompass the posterior 1-2 cm of the bladder wall; posteriorly, it is bounded by the mesorectal fascia. At this level, the lateral border is the sacrorectogenitopubic fascia. Seminal vesicle remnants, if present, should be included in the CTV if there is pathologic evidence of their involvement.
Consensus on postoperative PF-CTV for RT after prostatectomy was reached and is available as a CT image atlas on the RTOG website. This will allow uniformity in defining PF-CTV for clinical trials that include postprostatectomy RT.
Lung cancer screening using low-dose CT scanning reduces lung-cancer-specific and overall mortality in high-risk patients. A significant limitation of lung cancer screening is the false-positive ...rate. The American College of Radiology Lung Imaging Reporting and Data System (Lung-RADS) was designed to standardize reporting of low-dose lung cancer screening results and to decrease the false-positive rate without significantly compromising sensitivity. Implementing Lung-RADS can also improve cost-effectiveness. However, Lung-RADS has never been studied in a prospective fashion. It also does not have a specific reporting category for patients with isolated hilar and mediastinal adenopathy or pleural effusion in the absence of lung nodules. We report four such cases from our lung cancer screening program. We believe that this is a significant limitation of Lung-RADS and should be revised in its new version.
Quantitative radiomics features, extracted from medical images, characterize tumour-phenotypes and have been shown to provide prognostic value in predicting clinical outcomes. Stability of radiomics ...features extracted from apparent diffusion coefficient (ADC)-maps is essential for reliable correlation with the underlying pathology and its clinical applications. Within a multicentre, multi-vendor trial we established a method to analyse radiomics features from ADC-maps of ovarian (n = 12), lung (n = 19), and colorectal liver metastasis (n = 30) cancer patients who underwent repeated (<7 days) diffusion-weighted imaging at 1.5 T and 3 T. From these ADC-maps, 1322 features describing tumour shape, texture and intensity were retrospectively extracted and stable features were selected using the concordance correlation coefficient (CCC > 0.85). Although some features were tissue- and/or respiratory motion-specific, 122 features were stable for all tumour-entities. A large proportion of features were stable across different vendors and field strengths. By extracting stable phenotypic features, fitting-dimensionality is reduced and reliable prognostic models can be created, paving the way for clinical implementation of ADC-based radiomics.
Traumatic ocular injuries are a significant cause of blindness and visual deficits. In the setting of acute orbital trauma, urgent ophthalmologic evaluation and intervention are critical in ...preserving vision. However, in the acute trauma setting, clinical evaluation of the globe may be difficult in the presence of surrounding periorbital soft-tissue swelling and other associated injuries, and patient cooperation may be limited because of unresponsiveness, altered mentation, or sedation. Often, rapid access to imaging is part of the initial diagnostic evaluation, and radiologists may be the first to identify traumatic injuries of the globe. Because of this, radiologists should be familiar with normal orbital and globe anatomy at various imaging modalities and have a thorough understanding of the various patterns of ocular injury and their imaging appearances. Radiologists should also be familiar with the various mimics of ocular injury, including congenital and acquired conditions that may alter the shape of the globe, various types of ocular calcifications, and the different types of material used to treat retinal detachment. Such knowledge may help radiologists make accurate diagnoses, which facilitates prompt and appropriate patient care.
Clinical differentiation of folliculitis types is challenging. Dermoscopy supports the recognition of folliculitis etiology, but its diagnostic accuracy is not known.
To assess the diagnostic ...accuracy of dermoscopy for folliculitis.
This observational study included patients (N = 240) with folliculitis determined on the basis of clinical and dermoscopic assessments. A dermoscopic image of the most representative lesion was acquired for each patient. Etiology was determined on the basis of cytologic examination, culture, histologic examination, or manual hair removal (when ingrowing hair was detected) by dermatologist A. Dermoscopic images were evaluated according to predefined diagnostic criteria by dermatologist B, who was blinded to the clinical findings. Dermoscopic and definitive diagnoses were compared by dermatologist C.
Of the 240 folliculitis lesions examined, 90% were infections and 10% were noninfectious. Infectious folliculitis was caused by parasites (n = 71), fungi (n = 81), bacteria (n = 57), or 7 viruses (n = 7). Noninfectious folliculitis included pseudofolliculitis (n = 14), folliculitis decalvans (n = 7), and eosinophilic folliculitis (n = 3). The overall accuracy of dermoscopy was 73.7%. Dermoscopy showed good diagnostic accuracy for Demodex (88.1%), scabietic (89.7%), and dermatophytic folliculitis (100%), as well as for pseudofolliculitis (92.8%).
The diagnostic value of dermoscopy was calculated only for common folliculitis. Diagnostic reliability could not be calculated.
Dermoscopy is a useful tool for assisting in the diagnosis of some forms of folliculitis.
Abstract
The sense of agency is defined as the subjective experience that “I” am the one who is causing the action. Theoretical studies postulate that this subjective experience is developed through ...multistep processes extending from the sensorimotor to the cognitive level. However, it remains unclear how the brain processes such different levels of information and constitutes the neural substrates for the sense of agency. To answer this question, we combined two strategies: an experimental paradigm, in which self-agency gradually evolves according to sensorimotor experience, and a multivoxel pattern analysis. The combined strategies revealed that the sensorimotor, posterior parietal, anterior insula, and higher visual cortices contained information on self-other attribution during movement. In addition, we investigated whether the found regions showed a preference for self-other attribution or for sensorimotor information. As a result, the right supramarginal gyrus, a portion of the inferior parietal lobe (IPL), was found to be the most sensitive to self-other attribution among the found regions, while the bilateral precentral gyri and left IPL dominantly reflected sensorimotor information. Our results demonstrate that multiple brain regions are involved in the development of the sense of agency and that these show specific preferences for different levels of information.
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