Τετάρτη 18 Απριλίου 2018

Construction of an Anthropomorphic Phantom for Use in Evaluating Pediatric Airway Digital Tomosynthesis Protocols

Interpretation of radiolucent foreign bodies (FBs) is a common task charged to pediatric radiologists. The use of a motion compensated technique to decrease breathing motion on images would greatly decrease overall exposure to ionizing radiation and increase access to treatment yielding a great impact on clinical care. This study reports on the methodology and materials used to construct an in-house anthropomorphic phantom for investigating image quality in digital tomosynthesis protocols for volumetric imaging of the pediatric airway. Availability and cost of possible substitute materials were considered and simplifying assumptions were made. Two different modular phantoms were assembled in coronal slab layers using materials designed to approximate a one- and three-year-old thorax at diagnostic photon energies for use with digital tomosynthesis protocols such as those offered on GE's VolumeRAD application. Exposures were made using both phantoms with inserted food particles inside an oscillating airway. The goal of the phantom is to help evaluate (1) whether the currently used protocol is sufficient to image the airway despite breathing motion and (2) whether it is not, to find the optimal protocol by testing various commercially available protocols using this phantom. The affordable construction of the pediatric sized phantom aimed at optimizing GE's VolumeRAD protocol for airway foreign body imaging is demonstrated in this study which can be used to test VolumeRAD's ability to image the airways with and without a low-density foreign body within the airways.

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Giant dentinogenic ghost cell tumor: a case report

Dentinogenic ghost cell tumor (DGCT) is a rare, aggressive and benign odontogenic tumor that causes bone destruction and cortical expansion. We report a case of DGCT in a 38-years-old male, presenting an enormous extra-oral protrusion, that radiographically was predominantly radiolucent with radiopaque areas. Microscopically, it was observed a solid ameloblastomatous proliferation with pseudoglandular structures associated with clusters of ghost cells. Abundant dentinoid material adjacent to the epithelial sheets containing entrapped epithelial tumor cells were also evident.

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Response to letter to editor regarding CFOJ study

Thank you for the opportunity to respond to the Letter To The Editor (LTE) regarding our recently published study of CFOJ. We offer the following observations. As a general comment we wish to assure the readers that we are not attempting "to resurrect an orofacial pain concept that has come and gone several times in the past 30-40 years." Rather we are presenting the clinicopathogic findings of 331 new cases of a specific condition which appears to respond to a specific therapy in a significant percentage of patients.

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Oral cancer early detection: what will it take?

The estimated annual incidence of oral cavity and pharynx cancer in men (37,160) and in women (14,380) in the United States (U.S.) has, in 2018, surpassed the number of new cases of cervical cancer in women (13,240).1 Many of these new oral and pharyngeal cancer cases are occurring in younger adults. Eleven million U.S. men and 3.2 million U.S. women now harbor human papilloma virus (HPV) in the oral cavity.2 With dramatically increasing numbers of new oral and pharyngeal cancers in the U.S., driven in part by the HPV infection epidemic, what will it take to turn this tide?

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Preoperative radiotherapy and local excision of rectal cancer: Long-term results of a randomised study

It is uncertain whether local control is acceptable after preoperative radiotherapy and local excision (LE). An optimal preoperative dose/fractionation schedule has not yet been established.

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Dose-response in choroidal melanoma

In choroidal melanoma the radiation threshold dose for local control remains largely unknown. The present study examined a group of patients that received a wide range of minimum tumor dose in order to investigate a dose-response relationship. A literature review is performed to compare our results with available evidence in brachytherapy and charged particle external beam radiotherapy.

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Subacute Infarct Volume With Edema Correction in Computed Tomography Is Equivalent to Final Infarct Volume After Ischemic Stroke: Improving the Comparability of Infarct Imaging Endpoints in Clinical Trials

Objectives Final infarct volume is regularly used as an end point of tissue outcome in stroke trials; however, the reported volumes are most commonly derived from early follow-up imaging. Those volumes are significantly impaired by ischemic edema, which causes an overestimation of the true final lesion volume. As net water uptake within ischemic brain can be quantified densitometrically in computed tomography (CT) as recently described, we hypothesized that the final lesion volume can be better estimated by correcting the lesion volume in early follow-up for the corresponding proportion of edema. Materials and Methods After retrospective consecutive screening of the local registry, 20 patients with acute middle cerebral artery large vessel occlusion met the inclusion criteria with early and late follow-up CT; the latter acquired at least 4 weeks after admission. In early follow-up imaging 24 hours after onset, the proportion of edema contributing to the infarct lesion was calculated by quantifying the total volume of ischemic net water uptake. Edema volume was then subtracted from the total lesion volume to obtain edema-corrected lesion volumes. Finally, these corrected lesion volumes were compared with the final lesion volume on late follow-up serving as ground truth. Results The median lesion volume in the early follow-up was 115.1 mL (range, 21.9–539.9 mL) and significantly exceeded the median final lesion volume in the late follow-up CT, which was 86.6 mL (range, 11.2–399.0 mL; p

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Cervical Spine Prospective Feasibility Study

Abstract

Purpose

Diffusion tensor imaging (DTI) in flexion-extension may serve as a diagnostic tool to improve the sensitivity for detection of myelopathy. In this study, the feasibility and reproducibility of dynamic DTI in the cervical spinal cord was assessed in healthy volunteers and patients.

Methods

All subjects were examined in maximum neck flexion-extension in a 3T magnetic resonance imaging (MRI) scanner. Range of motion, space available for the spinal cord, fractional anisotropy (FA) and apparent diffusion coefficient (ADC) were measured and compared between the neck positions.

Results

Volunteers showed no variation in ADC and FA. In patients, extension produced higher ADC in the diseased than in the control segments (p = 0.0045). The ADC of the affected segments was higher in extension than in the neutral position (p = 0.0030) or in flexion (p = 0.0002). The FA was significantly lower in extension in patients at both the control level C2/3 (p = 0.0154) and the affected segment (p = 0.0187).

Conclusions

Dynamic DTI of the cervical spine is feasible and ADC increased in the patient group in extension. This finding may open a previously unexplored avenue to attempt an earlier identification of myelopathy.



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Different pixel pitch and maximum luminance of medical grade displays may result in different evaluations of digital radiography images

Abstract

Aim

To evaluate the effects of display pixel pitch and maximum luminance on intra- and inter-observer reproducibility and observer performance when evaluating chest lesions and bone fractures.

Materials and methods

This was a multi-institutional study for a retrospective interpretation of selected digital radiography images. Overall, 82 images were selected by senior radiologists, including 50 cases of chest lesions and 32 cases of bone fractures. These images were displayed at two pixel pitches (0.212 and 0.165 mm size pixels) and two maximum luminance values (250 and 500 cd/m2) and reviewed twice by senior and junior radiologists. All the observers had to indicate the likelihood of the presence of the lesions and to rate the relative confidence of their assessment. Cohen Kappa statistic was computed to estimate the reproducibility in correctly identifying lesions; for multi-reader-multi-case (MRMC) analysis, weighted Jackknife Alternative Free-response Receiver Operating Characteristic (wJAFROC) statistical tools was applied.

Results

The intra-radiologist and inter-observer reproducibility values were the highest for the 0.165 mm size pixel at 500 cd/m2 display, for both chest lesions and bone fractures evaluations. As regards chest lesions, observer performances were significantly greater with 0.165 mm size pixel display at 500 cd/m2 than with lower maximum luminance and/or larger pixel pitch displays. Concerning bone fractures, the performance obtained with 0.212 mm size pixel display at 250 cd/m2 was statistically lower than that obtained with 0.165 mm sixe pixel display at 500 cd/m2.

Conclusion

Our results indicate that an increased maximum luminance level and a decreased pixel pitch of medical-grade display improve the accuracy of detecting both chest lesions and bone fractures.



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Correction to: Solitary fibrous tumours in the extracranial head and neck region: correlation of CT and MR features with pathologic findings

Solitary fibrous tumours (SFTs) are rare, mesenchymal neoplasms. The purpose of this study was to analyse the radiological and clinicopathological features of SFTs in the extracranial head and neck region.



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Low-dose radiation use in diagnostic imaging and cancer therapy settings

Abstract

Current methods of radiation safety are characterized by age-old hypotheses that claim low doses of radiation, such as those received in diagnostic imaging and cancer treatment, increase the risk of cancer. The linear no-threshold hypothesis dates back to 70 years and has not been scientifically validated, yet it remains the driving force behind current regulatory policies concerning radiation exposure. The linear no-threshold hypothesis has birthed the "as low as reasonably achievable" concept that is commonly practiced in medical professions to limit radiation exposure. Both perpetuate an unscientific radiophobia stigma, while undermining the more likely result of stimulation of protective responses from the low doses of radiation. This article serves to reemphasize the fallacies of carcinogenic risk and to highlight the possible benefits of low-dose exposure in hopes of invalidating the concerns of physicians, the diagnostic imaging technologists, and patient populations that are subject to diagnostic imaging and cancer radiation therapies.



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IDoR2018 : Cardiac Imaging

Cardiac imaging has been chosen as the main theme of the day, to highlight the essential role that imaging professionals play in the detection, diagnosis and management of cardiac diseases, increasing the quality of care and treatment of patients.

Image result for IDoR 2018
Famous Radiology Blog https://ift.tt/1MM2hKr TeleRad Providers at https://ift.tt/1NgppuI Mail us at sales@teleradproviders.com


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Neuroimaging of Meckel’s cave in normal and disease conditions

Abstract

Meckel's cave is a dural recess in the posteromedial portion of the middle cranial fossa that acts as a conduit for the trigeminal nerve between the prepontine cistern and the cavernous sinus, and houses the Gasserian ganglion and proximal rootlets of the trigeminal nerve. It serves as a major pathway in perineural spread of pathologies such as head and neck neoplasms, automatically upstaging tumours, and is a key structure to assess in cases of trigeminal neuralgia. The purpose of this pictorial review is threefold: (1) to review the normal anatomy of Meckel's cave; (2) to describe imaging findings that identify disease involving Meckel's cave; (3) to present case examples of trigeminal and non-trigeminal processes affecting Meckel's cave.

Teaching points

Meckel's cave contains the trigeminal nerve ganglion and rootlets between the prepontine cistern and cavernous sinus.

Assessment is essential for perineural spread of disease and trigeminal neuralgia.

Key imaging: neural enhancement, enlargement, perineural fat/CSF effacement and skull base foraminal changes.



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Tip of the Iceberg Findings: Subtle Radiographic Abnormalities Indicating Significant Pathology in the Knee

Abstract

Purpose of Review

Knee injuries are common and radiographs remain the first line of study in the majority of cases. In many instances, subtle or small radiographic findings actually represent significant underlying pathology that requires expeditious diagnosis and treatment.

Recent Findings

By using a mechanistic search strategy, one that applies a comprehensive search for avulsions at ligamentous/tendinous/connective tissue attachments and potential sites of impaction, one may maximize the diagnostic accuracy of radiographic interpretation.

Summary

This article will provide a review of important indicators of ligament, tendon, and osseous injuries with an emphasis on their mechanism of injury.



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Imaging of Acute Traumatic Aortic Injury

Abstract

Purpose of Review

This article aims to review the key aspects of the imaging evaluation of acute traumatic aortic injury (ATAI) with an emphasis on factors that affect management of these patients.

Recent Findings

In the setting of trauma, the chest radiograph typically serves as the initial imaging evaluation and can be useful in detecting signs of mediastinal hematoma. In the current era, definitive diagnosis of ATAI is made with computed tomography (CT), where indirect and direct findings of ATAI can enable a confident diagnosis. Knowledge of potential technical and anatomic CT imaging pitfalls can prevent misdiagnosis of ATAI.

Summary

Diagnosis of ATAI in the setting of blunt or penetrating trauma relies heavily on timely and accurate imaging interpretation. Once the diagnosis is made, a meaningful report including appropriate descriptors of the characteristics and location of ATAI should be generated by the radiologist to help direct management.



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Subacute Infarct Volume With Edema Correction in Computed Tomography Is Equivalent to Final Infarct Volume After Ischemic Stroke: Improving the Comparability of Infarct Imaging Endpoints in Clinical Trials

Objectives Final infarct volume is regularly used as an end point of tissue outcome in stroke trials; however, the reported volumes are most commonly derived from early follow-up imaging. Those volumes are significantly impaired by ischemic edema, which causes an overestimation of the true final lesion volume. As net water uptake within ischemic brain can be quantified densitometrically in computed tomography (CT) as recently described, we hypothesized that the final lesion volume can be better estimated by correcting the lesion volume in early follow-up for the corresponding proportion of edema. Materials and Methods After retrospective consecutive screening of the local registry, 20 patients with acute middle cerebral artery large vessel occlusion met the inclusion criteria with early and late follow-up CT; the latter acquired at least 4 weeks after admission. In early follow-up imaging 24 hours after onset, the proportion of edema contributing to the infarct lesion was calculated by quantifying the total volume of ischemic net water uptake. Edema volume was then subtracted from the total lesion volume to obtain edema-corrected lesion volumes. Finally, these corrected lesion volumes were compared with the final lesion volume on late follow-up serving as ground truth. Results The median lesion volume in the early follow-up was 115.1 mL (range, 21.9–539.9 mL) and significantly exceeded the median final lesion volume in the late follow-up CT, which was 86.6 mL (range, 11.2–399.0 mL; p

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Positive Surgical Margins in Favorable-Stage Differentiated Thyroid Cancer.

Related Articles

Positive Surgical Margins in Favorable-Stage Differentiated Thyroid Cancer.

Am J Clin Oncol. 2018 Apr 16;:

Authors: Mercado CE, Drew PA, Morris CG, Dziegielewski PT, Mendenhall WM, Amdur RJ

Abstract
OBJECTIVE: The significance of positive margin in favorable-stage well-differentiated thyroid cancer is controversial. We report outcomes of positive-margin patients with a matched-pair comparison to a negative-margin group.
MATERIALS AND METHODS: A total of 25 patients with classic-histology papillary or follicular carcinoma, total thyroidectomy +/- node dissection, stage T1-3N0-1bM0, positive surgical margin at primary site, adjuvant radioactive iodine (I-131), and age older than 18 years were treated between 2003 and 2013. Endpoints were clinical and biochemical (thyroglobulin-only) recurrence-free survival. Matched-pair analysis involved a 1:1 match with negative-margin cases matched for overall stage and I-131 dose.
RESULTS: Recurrence-free survival in positive-margin patients was 71% at 10 years. No patient was successfully salvaged with additional treatment. Only 1 patient died of thyroid cancer. Recurrence-free survival at 10 years was worse with a positive (71%) versus negative (90%) margin (P=0.140).
CONCLUSIONS: Cure with a microscopically positive margin was suboptimal (71%) despite patients having classic-histology papillary and follicular carcinoma, favorable stage, and moderate-dose I-131 therapy.

PMID: 29664794 [PubMed - as supplied by publisher]



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123I-Labeled oxLDL Is Widely Distributed Throughout the Whole Body in Mice.

Related Articles

123I-Labeled oxLDL Is Widely Distributed Throughout the Whole Body in Mice.

Nucl Med Mol Imaging. 2018 Apr;52(2):144-153

Authors: Nakano A, Kawashima H, Miyake Y, Zeniya T, Yamamoto A, Koshino K, Temma T, Fukuda T, Fujita Y, Kakino A, Kanaya S, Sawamura T, Iida H

Abstract
Purpose: Oxidized low-density lipoprotein (oxLDL) plays a key role in endothelial dysfunction, vascular inflammation, and atherogenesis. The aim of this study was to assess blood clearance and in vivo kinetics of radiolabeled oxLDL in mice.
Methods: We synthesized 123I-oxLDL by the iodine monochloride method, and performed an uptake study in CHO cells transfected with lectin-like oxLDL receptor-1 (LOX-1). In addition, we evaluated the consistency between the 123I-oxLDL autoradiogram and the fluorescence image of DiI-oxLDL after intravenous injection for both spleen and liver. Whole-body dynamic planar images were acquired 10 min post injection of 123I-oxLDL to generate regional time-activity curves (TACs) of the liver, heart, lungs, kidney, head, and abdomen. Regional radioactivity for those excised tissues as well as the bladder, stomach, gut, and thyroid were assessed using a gamma counter, yielding percent injected dose (%ID) and dose uptake ratio (DUR). The presence of 123I-oxLDL in serum was assessed by radio-HPLC.
Results: The cellular uptakes of 123I-oxLDL were identical to those of DiI-oxLDL, and autoradiograms and fluorescence images also exhibited consistent distributions. TACs after injection of 123I-oxLDL demonstrated extremely fast kinetics. The radioactivity uptake at 10 min post-injection was highest in the liver (40.8 ± 2.4% ID). Notably, radioactivity uptake was equivalent throughout the rest of the body (39.4 ± 2.7% ID). HPLC analysis revealed no remaining 123I-oxLDL or its metabolites in the blood.
Conclusion: 123I-OxLDL was widely distributed not only in the liver, but also throughout the whole body, providing insight into the pathophysiological effects of oxLDL.

PMID: 29662563 [PubMed]



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Robotic ultrasound-guided facet joint insertion

Abstract

Purpose

Facet joint insertion is a common treatment of chronic pain in the back and spine. This procedure is often performed under fluoroscopic guidance, where the staff's repetitive radiation exposure remains an unsolved problem. Robotic ultrasound (rUS) has the potential to reduce or even eliminate the use of radiation by using ultrasound with a robotic-guided needle insertion. This work presents first clinical data of rUS-based needle insertions extending previous work of our group.

Methods

Our system implements an automatic US acquisition protocol combined with a calibrated needle targeting system. This approach assists the physician by positioning the needle holder on a trajectory selected in a 3D US volume of the spine.

Results

By the time of submission, nine facets were treated with our approach as first data from an ongoing clinical study. The insertion success rate was shown to be comparable to current clinical practice. Furthermore, US imaging offers additional anatomical context for needle trajectory planning.

Conclusion

This work shows first clinical data for robotic ultrasound-assisted facet joint insertion as a promising solution that can easily be incorporated into the clinical workflow. Presented results show the clinical value of such a system.



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Automatic planning of needle placement for robot-assisted percutaneous procedures

Abstract

Purpose

Percutaneous procedures allow interventional radiologists to perform diagnoses or treatments guided by an imaging device, typically a computed tomography (CT) scanner with a high spatial resolution. To reduce exposure to radiations and improve accuracy, robotic assistance to needle insertion is considered in the case of X-ray guided procedures. We introduce a planning algorithm that computes a needle placement compatible with both the patient's anatomy and the accessibility of the robot within the scanner gantry.

Methods

Our preoperative planning approach is based on inverse kinematics, fast collision detection, and bidirectional rapidly exploring random trees coupled with an efficient strategy of node addition. The algorithm computes the allowed needle entry zones over the patient's skin (accessibility map) from 3D models of the patient's anatomy, the environment (CT, bed), and the robot. The result includes the admissible robot joint path to target the prescribed internal point, through the entry point. A retrospective study was performed on 16 patients datasets in different conditions: without robot (WR) and with the robot on the left or the right side of the bed (RL/RR).

Results

We provide an accessibility map ensuring a collision-free path of the robot and allowing for a needle placement compatible with the patient's anatomy. The result is obtained in an average time of about 1 min, even in difficult cases. The accessibility maps of RL and RR covered about a half of the surface of WR map in average, which offers a variety of options to insert the needle with the robot. We also measured the average distance between the needle and major obstacles such as the vessels and found that RL and RR produced needle placements almost as safe as WR.

Conclusion

The introduced planning method helped us prove that it is possible to use such a "general purpose" redundant manipulator equipped with a dedicated tool to perform percutaneous interventions in cluttered spaces like a CT gantry.



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Downgrading of Breast Masses Suspicious for Cancer by Using Optoacoustic Breast Imaging.

Downgrading of Breast Masses Suspicious for Cancer by Using Optoacoustic Breast Imaging.

Radiology. 2018 Apr 17;:170500

Authors: Menezes GLG, Pijnappel RM, Meeuwis C, Bisschops R, Veltman J, Lavin PT, van de Vijver MJ, Mann RM

Abstract
Purpose To assess the ability of optoacoustic (OA) ultrasonography (US) to help correctly downgrade benign masses classified as Breast Imaging Reporting and Data System (BI-RADS) 4a and 4b to BI-RADS 3 or 2. Materials and Methods OA/US technology uses laser light to detect relative amounts of oxygenated and deoxygenated hemoglobin in and around suspicious breast masses. In this prospective, multicenter study, results of 209 patients with 215 breast masses classified as BI-RADS 4a or 4b at US are reported. Patients were enrolled between 2015 and 2016. Masses were first evaluated with US with knowledge of previous clinical information and imaging results, and from this information a US imaging-based probability of malignancy (POM) and BI-RADS category were assigned to each mass. The same masses were then re-evaluated at OA/US. During the OA/US evaluation, radiologists scored five OA/US features, and then reassigned an OA/US-based POM and BI-RADS category for each mass. BI-RADS downgrade and upgrade percentages at OA/US were assessed by using a weighted sum of the five OA feature scores. Results At OA/US, 47.9% (57 of 119; 95% CI: 0.39, 0.57) of benign masses classified as BI-RADS 4a and 11.1% (three of 27; 95% CI: 0.03, 0.28) of masses classified as BI-RADS 4b were correctly downgraded to BI-RADS 3 or 2. Two of seven malignant masses classified as BI-RADS 4a at US were incorrectly downgraded, and one of 60 malignant masses classified as BI-RADS 4b at US was incorrectly downgraded for a total of 4.5% (three of 67; 95% CI: 0.01, 0.13) false-negative findings. Conclusion At OA/US, benign masses classified as BI-RADS 4a could be downgraded in BI-RADS category, which would potentially decrease biopsies negative for cancer and short-interval follow-up examinations, with the limitation that a few masses may be inappropriately downgraded.

PMID: 29664342 [PubMed - as supplied by publisher]



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Cervical Cord T1-weighted Hypointense Lesions at MR Imaging in Multiple Sclerosis: Relationship to Cord Atrophy and Disability.

Cervical Cord T1-weighted Hypointense Lesions at MR Imaging in Multiple Sclerosis: Relationship to Cord Atrophy and Disability.

Radiology. 2018 Apr 17;:172311

Authors: Valsasina P, Aboulwafa M, Preziosa P, Messina R, Falini A, Comi G, Filippi M, Rocca MA

Abstract
Purpose To characterize the spatial distribution of cervical cord T1-weighted hypointense lesions in patients with multiple sclerosis (MS) and analyze their association with cord atrophy and disability. Materials and Methods For this prospective study that took place between 2014 and 2016, 3.0-T high-resolution T1-weighted cervical cord magnetic resonance (MR) images and clinical evaluations were obtained from 82 patients with relapsing-remitting MS (RRMS), 33 patients with secondary progressive MS (SPMS), 25 patients with primary progressive MS (PPMS), and 35 sex-matched healthy control participants. Hypointense cord lesions on T1-weighted imaging were identified and corresponding lesion masks were produced. A semiautomatic method on the basis of active surfaces was used to perform voxel-wise assessment (by using statistical parametric mapping and full factorial models) of T1-weighted hypointense lesion distribution and cord atrophy. Results T1-weighted hypointense cervical cord lesions were detected in 122 of 140 (87.1%) patients with MS. Lesions were preferentially located in the posterior (P = .01) and upper (P < .001) cervical cord. Lesion extent at C1/C2 and C5 was higher in patient with SPMS versus RRMS, and patients with PPMS versus RRMS and SPMS (P value range, <.001 to .05). Cord atrophy at upper cervical levels was found in patients with MS compared with control participants, especially in progressive MS (P value range, <.001 to .04). Partial overlap (r = 0.66; P < .001) occurred between regions with T1-weighted hypointense cord lesions and atrophy. Cord atrophy (r value range, -0.24 to -0.48; P < .001) and T1-weighted hypointense cord lesion extent (r value range, 0.36-0.42; P < .001) were correlated with clinical disability. Conclusion Hypointense lesions at T1-weighted imaging were observed in the cervical spinal cord of the majority of patients with MS and more widespread in progressive than in relapsing MS phenotypes. Both T1-weighted hypointense cord lesions and atrophy correlated with patient clinical disability.

PMID: 29664341 [PubMed - as supplied by publisher]



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Pancreatic Ductal Adenocarcinoma: Rim Enhancement at MR Imaging Predicts Prognosis after Curative Resection.

Pancreatic Ductal Adenocarcinoma: Rim Enhancement at MR Imaging Predicts Prognosis after Curative Resection.

Radiology. 2018 Apr 17;:172331

Authors: Lee S, Kim SH, Park HK, Jang KT, Hwang JA, Kim S

Abstract
Purpose To identify features at preoperative magnetic resonance (MR) imaging that could predict favorable prognosis after curative resection of pancreatic ductal adenocarcinoma (PDAC). Materials and Methods From January 2009 to December 2014, this retrospective study included 143 patients with surgically resected (ie, R0) PDAC who underwent preoperative MR imaging within 1 month before surgery. Clinical-pathologic and MR imaging findings for predicting disease-free survival (DFS) and overall survival (OS) were identified by using a Cox proportional hazards model. Important MR imaging features were compared with clinical-pathologic findings. Results Tumor size at histopathologic analysis was associated with both DFS and OS (hazard ratio per centimeter, 1.37; 95% confidence interval: 1.15, 1.63; P < .001 and hazard ratio, 1.44; 95% confidence interval: 1.20, 1.73; P < .001, respectively). Rim enhancement at dynamic contrast material-enhanced MR imaging was associated with significantly worse DFS and OS (hazard ratio, 1.72; 95% confidence interval: 1.05, 2.82; P = .030 and hazard ratio, 2.27; 95% confidence interval: 1.39, 3.69; P = .001, respectively). Diffusion-weighted imaging parameters, including diffusion restriction and apparent diffusion coefficient value, did not predict DFS or OS after resection of PDAC (all P > .05). Rim-enhancing lesions had more aggressive histologic tumor grades, less frequent remaining acini, and more frequent necrosis within the tumor compared with non-rim-enhancing pancreatic lesions (P = .002, P = .008, and P < .001, respectively). Conclusion Greater tumor size and rim enhancement were associated with lower DFS and OS rates after attempted curative resection of PDAC.

PMID: 29664340 [PubMed - as supplied by publisher]



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General Practitioners Referring Adults to MR Imaging for Knee Pain: A Randomized Controlled Trial to Assess Cost-effectiveness.

General Practitioners Referring Adults to MR Imaging for Knee Pain: A Randomized Controlled Trial to Assess Cost-effectiveness.

Radiology. 2018 Apr 17;:171383

Authors: van Oudenaarde K, Swart NM, Bloem JL, Bierma-Zeinstra SMA, Algra PR, Bindels PJE, Koes BW, Nelissen RGHH, Verhaar JAN, Luijsterburg PAJ, Reijnierse M, van den Hout WB

Abstract
Purpose To determine the cost-effectiveness of early referral by the general practitioner for magnetic resonance (MR) imaging compared with usual care alone in patients aged 18-45 years with traumatic knee symptoms. Materials and Methods Cost-utility analysis was performed parallel to a prospective multicenter randomized controlled trial in Dutch general practice. A total of 356 patients with traumatic knee symptoms were included from November 2012 to December 2015 (mean age, 33 years ± 8 [standard deviation]; 222 men [62%]). Patients were randomly assigned to usual care (n = 177; MR imaging was not performed, but patients were referred to an orthopedic surgeon when conservative treatment was unsatisfactory) or MR imaging (n = 179) within 2 weeks after injury. Main outcome measures were quality-adjusted life years (QALYs) and costs from a healthcare and societal perspective. Multiple imputation was used for missing data. The Student t test was used to assess differences in mean QALYs, costs, and net benefits. Results Mean QALYs were 0.888 in the MR imaging group and 0.899 in the usual care group (P = .255). Healthcare costs per patient were higher in the MR imaging group (€1109) than in the usual care group (€837) (P = .050), mainly due to higher costs for MR imaging, with no reduction in the number of referrals to an orthopedic surgeon in the MR imaging group. Conclusion MR imaging referral by the general practitioner was not cost-effective in patients with traumatic knee symptoms; in fact, MR imaging led to more healthcare costs, without an improvement in health outcomes.

PMID: 29664339 [PubMed - as supplied by publisher]



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Impact of Clinical History on Maximum PI-RADS Version 2 Score: A Six-Reader 120-Case Sham History Retrospective Evaluation.

Impact of Clinical History on Maximum PI-RADS Version 2 Score: A Six-Reader 120-Case Sham History Retrospective Evaluation.

Radiology. 2018 Apr 17;:172619

Authors: Shankar PR, Kaza RK, Al-Hawary MM, Masch WR, Curci NE, Mendiratta-Lala M, Sakala MD, Johnson TD, Davenport MS

Abstract
Purpose To assess the impact of clinical history on the maximum Prostate Imaging Recording and Data System (PI-RADS) version 2 (v2) score assigned to multiparametric magnetic resonance (MR) imaging of the prostate. Materials and Methods This retrospective cohort study included 120 consecutively selected multiparametric prostate MR imaging studies performed between November 1, 2016, and December 31, 2016. Sham clinical data in four domains (digital rectal examination, prostate-specific antigen level, plan for biopsy, prior prostate cancer history) were randomly assigned to each case by using a balanced orthogonal design. Six fellowship-trained abdominal radiologists independently reviewed the sham data, actual patient age, and each examination while they were blinded to interreader scoring, true clinical data, and histologic findings. Readers were told the constant sham histories were true, believed the study to be primarily investigating interrater agreement, and were asked to assign a maximum PI-RADS v2 score to each case. Linear regression was performed to assess the association between clinical variables and maximum PI-RADS v2 score designation. Intraclass correlation coefficients (ICCs) were obtained to compare interreader scoring. Results Clinical information had no significant effect on maximum PI-RADS v2 scoring for any of the six readers (P = .09-.99, 42 reader-variable pairs). Distributions of maximum PI-RADS v2 scores in the research context were similar to the distribution of the scores assigned clinically and had fair-to-excellent pairwise interrater agreement (ICC range: 0.53-0.76). Overall interrater agreement was good (ICC: 0.64; 95% confidence interval: 0.57, 0.71). Conclusion Clinical history does not appear to be a substantial bias in maximum PI-RADS v2 score assignment. This is potentially important for clinical nomograms that plan to incorporate PI-RADS v2 score and clinical data into their algorithms (ie, PI-RADS v2 scoring is not confounded by clinical data).

PMID: 29664338 [PubMed - as supplied by publisher]



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Pancreatic Stiffness Quantified with MR Elastography: Relationship to Postoperative Pancreatic Fistula after Pancreaticoenteric Anastomosis.

Pancreatic Stiffness Quantified with MR Elastography: Relationship to Postoperative Pancreatic Fistula after Pancreaticoenteric Anastomosis.

Radiology. 2018 Apr 17;:170450

Authors: Shi Y, Liu Y, Gao F, Liu Y, Tao S, Li Y, Glaser KJ, Ehman RL, Guo Q

Abstract
Purpose To describe the relationship between conventional magnetic resonance (MR) imaging parameters and MR elastography of the pancreas in association with pancreatic histologic features and occurrence of postoperative pancreatic fistula (POPF). Materials and Methods Patients who underwent preoperative MR imaging (MR elastography and diffusion-, T1-, and T2-weighted imaging) followed by pancreatectomy with pancreaticoenteric anastomosis were included. The relationships between preoperative MR imaging parameters, demographic data, and intraoperative factors with POPF risk were analyzed with logistic regression analyses. The correlation of MR imaging parameters with histologic characteristics was evaluated with multivariate regression analysis. Results A total of 112 patients (64 men, 48 women; median age, 58 years) were evaluated. Forty-two patients (37.5%) developed POPF and 20 (17.9%) developed high-grade POPF (grades B and C). Lower pancreatic stiffness (≤1.43 kPa; odds ratio [OR], 9.196; 95% confidence interval [CI]: 1.92, 43.98), nondilated main pancreatic duct (MPD) diameter (<3 mm; OR, 7.298; 95% CI: 1.51, 35.34), and larger stump area (≥211 mm2; OR, 9.210; 95% CI: 1.53, 55.26) were risk factors for POPF. Lower pancreatic stiffness (≤1.27 kPa; OR, 8.389; 95% CI: 1.88, 37.41) was the only independent predictor of high-grade POPF. Log-transformed pancreatic stiffness was independently associated with fibrosis (β = 0.060; 95% CI: 0.052, 0.068), acinar atrophy (β = 0.015; 95% CI: 0.003, 0.028), and lipomatosis (β = -0.016; 95% CI: -0.026, -0.006). Conclusion Preoperative MR assessment of pancreatic stiffness, MPD diameter, and stump area are important predictors of POPF.

PMID: 29664337 [PubMed - as supplied by publisher]



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Left Ventricular Myocardial Deformation on Cine MR Images: Relationship to Severity of Disease and Prognosis in Amyloid Light-Chain Amyloidosis.

Left Ventricular Myocardial Deformation on Cine MR Images: Relationship to Severity of Disease and Prognosis in Amyloid Light-Chain Amyloidosis.

Radiology. 2018 Apr 17;:172435

Authors: Wan K, Sun J, Yang D, Liu H, Wang J, Cheng W, Zhang Q, Zeng Z, Zhang T, Greiser A, Jolly MP, Han Y, Chen Y

Abstract
Purpose To measure left ventricular (LV) myocardial strain with cine magnetic resonance (MR) imaging and a deformable registration algorithm (DRA) and to assess the prognostic value of myocardial strain in patients with light-chain (AL) amyloidosis. Materials and Methods In this prospective study, 78 consecutive patients with AL amyloidosis who underwent contrast material-enhanced cardiac MR imaging were enrolled at West China Hospital. LV myocardial strains and late gadolinium enhancement (LGE) were evaluated. Association between myocardial strain and all-cause mortality was analyzed with the stepwise Cox regression model. Results Global longitudinal strain (GLS) and global circumferential strain (GCS) were significantly lower in the no or nonspecific LGE group compared with the subendocardial LGE and transmural LGE groups (mean GLS, -10% ± 3 [standard deviation] vs -7% ± 3 vs -4% ± 1; P < .001) (mean GCS, -13% ± 3 vs -11% ± 3 vs -7% ± 2; P < .001). GLS and GCS were reduced in patients without clinical cardiac amyloidosis (mean GLS, -13% ± 3 vs -16% ± 2; P = .005) (mean GCS, -16% ± 1 vs -19% ± 2; P = .02). Circumferential and radial strains were impaired in basal segments in accordance with the distribution of LGE. Multivariate Cox analysis revealed that GCS (hazard ratio [HR] = 1.16 per 1% absolute decrease; 95% confidence interval [CI]: 1.03, 1.31; P = .02) and the presence of transmural LGE (HR = 1.75; 95% CI: 1.10, 2.80; P = .02) were independent predictors of all-cause mortality after adjustment for LV ejection fraction, right ventricular ejection fraction, LV mass index, GLS, and global radial strain. Conclusion Strain parameters derived with cine MR imaging-based DRA may be a new noninvasive imaging marker with which to evaluate the extent of cardiac amyloid infiltration and may offer independent prognostic information for all-cause mortality in patients with AL amyloidosis.

PMID: 29664336 [PubMed - as supplied by publisher]



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Anatomical feasibility study of flexor hallucis longus transfer in treatment of Achilles tendon and posteromedial portal of ankle arthroscopy.

Related Articles

Anatomical feasibility study of flexor hallucis longus transfer in treatment of Achilles tendon and posteromedial portal of ankle arthroscopy.

Surg Radiol Anat. 2018 Apr 16;:

Authors: Mao H, Wang L, Dong W, Liu Z, Yin W, Xu D, Wapner KL

Abstract
PURPOSE: The aim of this study was to evaluate the occurrence of anatomical variations of the musculotendinous junction of the flexor hallucis longus (FHL) muscle, the relationship between FHL tendon or muscle and the tibial neurovascular bundle at the level of the posterior ankle joint in human cadavers.
METHODS: Seventy embalmed feet from 20 male and 15 female cadavers, the cadavers' mean age was 65.4 (range from 14 to 82) years, were dissected and anatomically classified to observe FHL muscle morphology define the relationship between FHL tendon or muscle and the tibial neurovascular bundle. The distance between the musculotendinous junction and the relationship between FHL tendon or muscle and the tibial neurovascular bundle was determined.
RESULTS: Three morphology types of FHL muscle were identified: a long lateral and shorter medial muscle belly, which was observed in 63 specimens (90%); equal length medial and lateral muscle bellies, this variant was only observed in five specimens (7.1%); one lateral and no medial muscle belly, which was observed in two specimens (2.9%). No statistically significant difference was observed according to gender or side (p > 0.05). Two patterns were identified and described between FHL tendon or muscle and the tibial neurovascular bundle. Pattern 1, the distance between the neurovascular bundle and FHL tendon was 3.46 mm (range 2.34-8.84, SD = 2.12) which was observed in 66 specimens (94.3%); Pattern 2, there was no distance which was observed in four specimens (5.7%).
CONCLUSION: Knowing FHL muscle morphology, variations provide new important insights into secure planning and execution of a FHL transfer for Achilles tendon defect as well as for the interpretation of ultrasound and magnetic resonance images. With posterior arthroscopic for the treatment of various ankle pathologies, posteromedial portal may be introduced into the posterior aspect of the ankle without gross injury to the tibial neurovascular structures because of the gap between the neurovascular bundle and FHL tendon.

PMID: 29663091 [PubMed - as supplied by publisher]



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Diagnostic performance of 18 F-FDG PET/CT and whole-body MRI before and early after treatment of multiple myeloma: a prospective comparative study

Abstract

Objective

To determine the diagnostic accuracy of WB-MRI and 18F-FDG PET/CT in detecting infiltration pattern, disease activity, and response to treatment in patients with multiple myeloma (MM).

Materials and methods

Fifty-six patients with confirmed MM were included in the present study for pre-treatment evaluation. Among these individuals, 22 patients were available for the post-treatment evaluation of response to therapy. All patients were imaged with both WB-MRI and 18F-FDG PET/CT. All radiographic findings of infiltration pattern, disease activity, and response to therapy were compared. The diagnostic performance of both modalities was estimated using bone marrow aspirate and biopsy as the reference test.

Results

For detection of active myelomatous tissue at diagnosis, WB-MRI achieved higher sensitivity (94%) than 18F-FDG PET/CT (75%) (p = 0.0039), whereas both modalities achieved the same specificity (80%). For detection of residual myelomatous tissue after treatment, 18F-FDG PET/CT achieved higher specificity (86%) than WB-MRI (43%) (p = 0.0081), whereas both modalities achieved the same sensitivity (75%).

Conclusion

WB-MRI is more sensitive than 18F-FDG PET/CT in the diagnosis of MM before treatment; however, 18F-FDG PET/CT is more specific than WB-MRI in detecting residual involvement in treated patients.



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EUROPEAN SOCIETY OF NEURORADIOLOGY



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EUROPEAN SOCIETY OF NEURORADIOLOGY



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Intraosseous venous structures adjacent to the jugular tubercle associated with an anterior condylar dural arteriovenous fistula

Abstract

Purpose

Although involvement of the osseous component with an anterior condylar dural arteriovenous fistula (AC-DAVF) has been frequently described, osseous venous structures in which AC-DAVFs develop have not been fully elucidated. We investigated osseous venous structures adjacent to the hypoglossal canal in normal controls and patients with AC-DAVFs.

Methods

The study included 50 individuals with unruptured aneurysms as normal controls and seven patients with AC-DAVFs. Osseous venous structures adjacent to the hypoglossal canal in normal controls were analyzed using computed tomography (CT) digital subtraction venography. In patients with AC-DAVFs, the fistulous pouches, draining veins, and surrounding venous structures were examined using cone beam CT.

Results

In 46.0% of laterals in normal controls, osseous venous structures were visualized within the jugular tubercle superomedially to the hypoglossal canal. We named these structures the jugular tubercle venous complex (JTVC). The JTVC was always continuous with the anterior condylar vein and was sometimes connected to surrounding venous channels. We detected nine fistulous pouches in the seven patients with AC-DAVFs. The fistulous pouches were in the JTVC (33.3%), anterior condylar vein (33.3%), and other venous channels within the exoccipital region (33.3%).

Conclusion

Although the JTVC is a venous structure frequently found in normal people, it had not been investigated until now. The venous channel between the anterior condylar vein and JTVC is a common origin site for AC-DAVFs, and it was associated with 66.6% of the AC-DAVF cases in the current study.



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