Πέμπτη, 15 Μαρτίου 2018

Once-weekly versus every-other-day stereotactic body radiotherapy in patients with prostate cancer (PATRIOT): A phase 2 randomized trial

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Publication date: Available online 15 March 2018
Source:Radiotherapy and Oncology
Author(s): Harvey C. Quon, Aldrich Ong, Patrick Cheung, William Chu, Hans T. Chung, Danny Vesprini, Amit Chowdhury, Dilip Panjwani, Geordi Pang, Renee Korol, Melanie Davidson, Ananth Ravi, Boyd McCurdy, Liying Zhang, Alexandre Mamedov, Andrea Deabreu, Andrew Loblaw
Background and purposeProstate stereotactic body radiotherapy (SBRT) regimens differ in time, dose, and fractionation. We completed a multicentre, randomized phase II study to investigate the impact of overall treatment time on quality of life (QOL).Material and methodsMen with low and intermediate-risk prostate cancer were randomly assigned to 40 Gy in 5 fractions delivered once per week (QW) vs. every other day (EOD). QOL was assessed using the Expanded Prostate Cancer Index Composite. The primary endpoint was the proportion with a minimum clinically important change (MCIC) in bowel QOL during the acute (≤12 week) period, and analysis was by intention-to-treat. ClinicalTrials.gov NCT01423474.Results152 men from 3 centres were randomized with median follow-up of 47 months. Patients treated QW had superior acute bowel QOL with 47/69 (68%) reporting a MCIC compared to 63/70 (90%) treated EOD (p = 0.002). Fewer patients treated QW reported moderate–severe problems with bowel QOL during the acute period compared with EOD (14/70 [20%] vs. 40/70 [57%], p < 0.001). Acute urinary QOL was also better in the QW arm, with 52/67 (78%) vs 65/69 (94%) experiencing a MCIC (p = 0.006). There were no significant differences in late urinary or bowel QOL at 2 years or last follow-up.ConclusionProstate SBRT delivered QW improved acute bowel and urinary QOL compared to EOD. Patients should be counselled regarding the potential for reduced short-term toxicity and improved QOL with QW prostate SBRT.



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Interaction Should Guide Management Decisions [LETTERS]



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Reply: [LETTERS]



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Anatomic Malformations of the Middle and Inner Ear in 22q11.2 Deletion Syndrome: Case Series and Literature Review [HEAD & NECK]

BACKGROUND AND PURPOSE:

The 22q11.2 deletion syndrome is characterized by a heterogenic phenotype, including hearing loss. The underlying cause of hearing loss, especially sensorineural hearing loss, is not yet clear. Therefore, our objective was to describe anatomic malformations in the middle and inner ear in patients with 22q11.2 deletion syndrome.

MATERIALS AND METHODS:

A retrospective case series was conducted in 2 tertiary referral centers. All patients with 22q11.2 deletion syndrome who had undergone CT or MR imaging of the temporal bones were included. Radiologic images were evaluated on predetermined parameters, including abnormalities of the ossicular chain, cochlea, semicircular canals, and vestibule.

RESULTS:

There were 26 patients (52 ears) with a CT or MR imaging scan available. A dense stapes superstructure was found in 18 ears (36%), an incomplete partition type II was suspected in 12 cochleas (23%), the lateral semicircular canal was malformed with a small bony island in 17 ears (33%), and the lateral semicircular canal and vestibule were fused to a single cavity in 15 ears (29%).

CONCLUSIONS:

Middle and inner ear abnormalities were frequently encountered in our cohort, including malformations of the lateral semicircular canal.



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Brain Diffusion Abnormalities in Children with Tension-Type and Migraine-Type Headaches [PEDIATRICS]

BACKGROUND AND PURPOSE:

Tension-type and migraine-type headaches are the most common chronic paroxysmal disorders of childhood. The goal of this study was to compare regional cerebral volumes and diffusion in tension-type and migraine-type headaches against published controls.

MATERIALS AND METHODS:

Patients evaluated for tension-type or migraine-type headache without aura from May 2014 to July 2016 in a single center were retrospectively reviewed. Thirty-two patients with tension-type headache and 23 with migraine-type headache at an average of 4 months after diagnosis were enrolled. All patients underwent DWI at 3T before the start of pharmacotherapy. Using atlas-based DWI analysis, we determined regional volumetric and diffusion properties in the cerebral cortex, thalamus, caudate, putamen, globus pallidus, hippocampus, amygdala, nucleus accumbens, brain stem, and cerebral white matter. Multivariate analysis of covariance was used to test for differences between controls and patients with tension-type and migraine-type headaches.

RESULTS:

There were no significant differences in regional brain volumes between the groups. Patients with tension-type and migraine-type headaches showed significantly increased ADC in the hippocampus and brain stem compared with controls. Additionally, only patients with migraine-type headache showed significantly increased ADC in the thalamus and a trend toward increased ADC in the amygdala compared with controls.

CONCLUSIONS:

This study identifies early cerebral diffusion changes in patients with tension-type and migraine-type headaches compared with controls. The hypothesized mechanisms of nociception in migraine-type and tension-type headaches may explain the findings as a precursor to structural changes seen in adult patients with chronic headache.



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Randomized Assessment of the Safety and Efficacy of Intra-Arterial Infusion of Autologous Stem Cells in Subacute Ischemic Stroke [INTERVENTIONAL]

BACKGROUND AND PURPOSE:

Stroke is a debilitating illness for which treatment window is limited. Most patients present to the healthcare facility beyond that window. Autologous stem cells have shown some promise for this group of patients. This study was performed to evaluate the safety and the efficacy of intra-arterial infusion of bone marrow–derived mononuclear cells in patients with middle cerebral artery ischemic stroke.

MATERIALS AND METHODS:

A prospective, randomized, open-label, blinded–end point study was performed from July 2015 to June 2016. Of 229 patients with acute stroke who presented to the hospital during this period, 20 patients who satisfied the inclusion/exclusion criteria were included and randomized into the control and intervention groups. Intra-arterial stem cell infusion into the ipsilateral MCA was performed in the patients in the intervention group at 8–15 days post-stroke ictus. Final analysis at 6 months was performed for primary (safety) and secondary outcomes (efficacy).

RESULTS:

When we compared the primary end point of the study, no procedure-related mortality, complication, new infarct, or symptomatic intracranial hemorrhage was seen in the intervention group. When we compared the secondary end point of good clinical outcome, 8 (80%) patients in the intervention group showed good clinical outcome (modified Rankin Scale score < 2) with 4 (40%) patients in the control group achieving this (95% confidence interval for good outcome in patients with stem cell infusion, 49.03–94.3, and without stem cell infusion, 16.82–68.73; P = .068).

CONCLUSIONS:

Intra-arterial infusion of stem cells can be carried out safely in the subacute stage of ischemic stroke. Improved clinical outcomes were observed with intra-arterial stem cell therapy; however, studies with larger cohorts are needed to validate the results.



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Endovascular Treatment of Very Large and Giant Intracranial Aneurysms: Comparison between Reconstructive and Deconstructive Techniques--A Meta-Analysis [INTERVENTIONAL]

BACKGROUND:

The safety and efficacy of reconstructive and deconstructive endovascular treatments of very large/giant intracranial aneurysms are not completely clear.

PURPOSE:

Our aim was to compare treatment-related outcomes between these 2 techniques.

DATA SOURCES:

A systematic search of 3 data bases was performed for studies published from 1990 to 2017.

STUDY SELECTION:

We selected series of reconstructive and deconstructive treatments with >10 patients.

DATA ANALYSIS:

Random-effects meta-analysis was used to analyze occlusion rates, complications, and neurologic outcomes.

DATA SYNTHESIS:

Thirty-nine studies evaluating 894 very large/giant aneurysms were included. Long-term occlusion of unruptured aneurysms was 71% and 93% after reconstructive and deconstructive treatments, respectively (P = .003). Among unruptured aneurysms, complications were lower after parent artery occlusion (16% versus 30%, P = .05), whereas among ruptured lesions, complications were lower after reconstructive techniques (34% versus 38%). Parent artery occlusion in the posterior circulation had higher complications compared with in the anterior circulation (36% versus 15%, P = .001). Overall, coiling yielded lower complication and occlusion rates compared with flow diverters and stent-assisted coiling. Complication rates of flow diversion were lower in the anterior circulation (17% versus 41%, P < .01). Among unruptured lesions, early aneurysm rupture (within 30 days) was slightly higher after reconstructive treatment (5% versus 0%, P = .08) and after flow diversion alone compared with flow diversion plus coiling (7% versus 0%).

LIMITATIONS:

Limitations were selection and publication biases.

CONCLUSIONS:

Parent artery occlusion allowed high rates of occlusion with an acceptable rate of complications for unruptured, anterior circulation aneurysms. Coiling should be preferred for posterior circulation and ruptured lesions, whereas flow diversion is relatively safe and effective for unruptured anterior circulation aneurysms.



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Evaluation of the Normal Cochlear Second Interscalar Ridge Angle and Depth on 3D T2-Weighted Images: A Tool for the Diagnosis of Scala Communis and Incomplete Partition Type II [HEAD & NECK]

BACKGROUND AND PURPOSE:

Cochlear malformations may be be subtle on imaging studies. The purpose of this study was to evaluate the angle and depth of the lateral second interscalar ridge or notch in ears without sensorineural hearing loss (normal ears) and compare them with ears that have a documented incomplete type II partition malformation.

MATERIALS AND METHODS:

The second interscalar ridge notch angle and depth were measured on MR imaging in normal ears by a single experienced neuroradiologist. The images of normal and incomplete partition II malformation ears were then randomly mixed for 2 novice evaluators to measure both the second interscalar ridge notch angle and depth in a blinded manner. For the mixed group, interobserver agreement was calculated, normal and abnormal ear measurements were compared, and receiver operating characteristic curves were generated.

RESULTS:

The 94 normal ears had a mean second interscalar ridge angle of 80.86° ± 11.4° and depth of 0.54 ± 0.14 mm with the 98th percentile for an angle of 101° and a depth of 0.3 mm. In the mixed group, agreement between the 2 readers was excellent, with significant differences for angle and depth found between normal and incomplete partition type II ears for angle and depth on average (P < .001). Receiver operating characteristic cutoffs for delineating normal from abnormal ears were similar for both readers (depth, 0.31/0.34 mm; angle, 114°/104°).

CONCLUSIONS:

A measured angle of >114° and a depth of the second interscalar ridge notch of ≤0.31 mm suggest the diagnosis of incomplete partition type II malformation and scala communis. These measurements can be accurately made by novice readers.



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European Multicenter Study for the Evaluation of a Dual-Layer Flow-Diverting Stent for Treatment of Wide-Neck Intracranial Aneurysms: The European Flow-Redirection Intraluminal Device Study [INTERVENTIONAL]

BACKGROUND AND PURPOSE:

Endoluminal reconstruction with flow-diverting stents represents a widely accepted technique for the treatment of complex intracranial aneurysms. This European registry study analyzed the initial experience of 15 neurovascular centers with the Flow-Redirection Intraluminal Device (FRED) system.

MATERIALS AND METHODS:

Consecutive patients with intracranial aneurysms treated with the FRED between February 2012 and March 2015 were retrospectively reviewed. Complications and adverse events, transient and permanent morbidity, mortality, and occlusion rates were evaluated.

RESULTS:

During the defined study period, 579 aneurysms in 531 patients (median age, 54 years; range, 13–86 years) were treated with the FRED. Seven percent of patients were treated in the acute phase (≤3 days) of aneurysm rupture. The median aneurysm size was 7.6 mm (range, 1–36.6 mm), and the median neck size 4.5 mm (range, 1–30 mm). Angiographic follow-up of >3 months was available for 516 (89.1%) aneurysms. There was progressive occlusion witnessed with time, with complete occlusion in 18 (20%) aneurysms followed for up to 90 ± 14 days, 141 (82.5%) for 180 ± 20 days, 116 (91.3%) for 1 year ± 24 days, and 122 (95.3%) aneurysms followed for >1 year. Transient and permanent morbidity occurred in 3.2% and 0.8% of procedures, respectively. The overall mortality rate was 1.5%.

CONCLUSIONS:

This retrospective study in real-world patients demonstrated the safety and efficacy of the FRED for the treatment of intracranial aneurysms. In most cases, treatment with a single FRED resulted in complete angiographic occlusion at 1 year.



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The Importance of Flexion MRI in Hirayama Disease with Special Reference to Laminodural Space Measurements [SPINE]

BACKGROUND AND PURPOSE:

Hirayama disease is a benign focal amyotrophy of the distal upper limbs involving C7, C8, and T1 segmental myotomes with sparing of the brachioradialis and proximal muscles of the upper limb innervated by C5–6 myotomes. The objective of the present study was to study the utility of MR imaging in young patients presenting with weakness and wasting of the distal upper extremity and to evaluate the importance of the laminodural space during flexion cervical MR imaging.

MATERIALS AND METHODS:

This was a prospective cross-sectional study conducted from January 2014 to July 2017 in a tertiary care center from Northeast India. Forty-five patients with clinically definite Hirayama disease underwent electrophysiologic evaluation followed by MR imaging of the cervical spine.

RESULTS:

The mean age at recruitment was 22.8 ± 5.5 years. Forty patients (88.9%) had unilateral and 5 (11.1%) had bilateral upper extremity involvement. Cervical cord T2-weighted hyperintensities were demonstrated in 16 patients (35.6%), of which 15 (33.3%) had anterior horn cell hyperintensities. Flexion MR imaging showed loss of the posterior dural attachment, forward shifting of the posterior dural sac with postcontrast enhancement, and prominent posterior epidural venous plexus in all patients. The laminodural space at maximum forward shifting of the posterior dural sac ranged from 3 to 9.8 mm, with a mean distance of 5.99 mm (95% confidence interval, 5.42–6.57 mm).

CONCLUSIONS:

Flexion cervical MR imaging is a very useful investigation in diagnosing Hirayama disease. The increase in the laminodural space and the presence of cervical cord flattening during flexion are essential for diagnosis.



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Localized Marked Elongation of the Distal Internal Carotid Artery with or without PHACE Syndrome: Segmental Dolichoectasia of the Distal Internal Carotid Artery [ADULT BRAIN]

BACKGROUND AND PURPOSE:

Segmental intracranial dolichoectasia of the distal ICA is a feature of PHACE syndrome or a sporadic phenomenon. We evaluated the relationship between intracranial dolichoectasia of the distal ICA and PHACE syndrome and illustrated the characteristic radiologic findings of the lesions.

MATERIALS AND METHODS:

Intracranial dolichoectasia of the distal ICA was identified in 20 patients at our institution from 2005 to 2016 through a review of diagnostic cerebral angiography results. All radiologic images were reviewed to determine the vascular morphologic dispositions around the distal ICA, including dysplasia, mural calcification, vessel wall enhancement, lumen narrowing, and aneurysm formation. Medical records were reviewed to determine the symptoms of PHACE syndrome. Subsequently, the correlation between radiologic findings and PHACE syndrome was assessed.

RESULTS:

In this cohort, which had a strong female predominance (male/female ratio= 2:18), intracranial dolichoectasia had a more ipsilateral vascular morphologic disposition. Mural calcification was detected more frequently in elderly patients, whereas vessel wall enhancement was detected more frequently in younger patients. Follow-up images showed a slow progression of the lesions. However, no significant differences in the vascular morphologic disposition and brain structural changes were observed between patients with (n = 11) and without (n = 9) PHACE syndrome.

CONCLUSIONS:

The striking elongation and tortuosity of the distal ICA generally appeared to be a type of congenital lesion occurring early in embryogenesis as either a sporadic phenomenon or an arterial change associated with PHACE syndrome. Imaging findings revealed various mural abnormalities with a benign clinical course.



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Arterial Spin-Labeling Improves Detection of Intracranial Dural Arteriovenous Fistulas with MRI [ADULT BRAIN]

BACKGROUND AND PURPOSE:

Intracranial dural arteriovenous fistulas carry a risk of substantial neurologic complications but can be difficult to detect on structural MR imaging and TOF-MRA. The purpose of this study was to assess the accuracy and added value of 3D pseudocontinuous arterial spin-labeling MR imaging for the detection of these lesions.

MATERIALS AND METHODS:

This retrospective study included 39 patients with a dural arteriovenous fistula and 117 controls who had undergone both DSA and MR imaging with pseudocontinuous arterial spin-labeling. Two neuroradiologists blinded to the DSA results independently assessed MR imaging with and without pseudocontinuous arterial spin-labeling. They recorded specific signs, including venous arterial spin-labeling signal, and the likelihood of a dural arteriovenous fistula using a 5-point Likert scale. Logistic regression and receiver operating characteristic analyses were performed to determine the accuracy of specific signs and the added value of pseudocontinuous arterial spin-labeling. Interobserver agreement was determined by using statistics.

RESULTS:

Identification of the venous arterial spin-labeling signal had a high sensitivity (94%) and specificity (88%) for the presence a dural arteriovenous fistula. Receiver operating characteristic analysis showed significant improvement in diagnostic performance with the addition of pseudocontinuous arterial spin-labeling in comparison with structural MR imaging (area under the receiver operating characteristic curve = 0.179) and a trend toward significant improvement in comparison with structural MR imaging with time-of-flight MRA (area under the receiver operating characteristic curve = 0.043). Interobserver agreement for the presence of a dural arteriovenous fistula improved substantially and was almost perfect with the addition of pseudocontinuous arterial spin-labeling ( = 0.92).

CONCLUSIONS:

Venous arterial spin-labeling signal has high sensitivity and specificity for the presence of a dural arteriovenous fistula, and the addition of pseudocontinuous arterial spin-labeling increases confidence in the diagnosis of this entity on MR imaging.



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MRI Characteristics of Primary Tumors and Metastatic Lesions in Molecular Subgroups of Pediatric Medulloblastoma: A Single-Center Study [PEDIATRICS]

BACKGROUND AND PURPOSE:

Molecular grouping of medulloblastoma correlates with prognosis and supports the therapeutic strategy. We provide our experience with the imaging features of primary and metastatic disease in relation to the molecular groups.

MATERIALS AND METHODS:

One hundred nineteen consecutive patients (mean age, 7.3 ± 3.8 years at diagnosis; male, 79 [66.4%]) with a confirmed diagnosis of medulloblastoma and interpretable pretreatment MRIs were retrieved from our data base from January 2000 to December 2016. Each patient was assigned to wingless, sonic hedgehog, group 3, or group 4 molecular groups. Then, we determined the imaging features of both primary and metastatic/recurrent disease predictive of molecular groups.

RESULTS:

In addition to recently reported predictors based on primary tumor, including cerebellar peripheral location for sonic hedgehog (adjusted odds ratio = 9, P < .0001), minimal enhancement of primary group 4 tumor (adjusted odds ratio = 5.2, P < .0001), and cerebellopontine angle location for wingless (adjusted odds ratio = 1.4, P = .03), ependymal metastasis with diffusion restriction and minimal postcontrast enhancement ("mismatching pattern") (adjusted odds ratio = 2.8, P = .001) for group 4 and spinal metastasis for group 3 (adjusted odds ratio = 1.9, P = .01) also emerged as independent predictors of medulloblastoma molecular groups. Specifically, the presence of a metastasis in the third ventricular infundibular recess showing a mismatching pattern was significantly associated with group 4 (P = .02).

CONCLUSIONS:

In addition to imaging features of primary tumors, some imaging patterns of metastatic dissemination in medulloblastoma seem characteristic, perhaps even specific to certain groups. This finding could further help in differentiating molecular groups, specifically groups 3 and 4, when the characteristics of the primary tumor overlap.



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Once-weekly versus every-other-day stereotactic body radiotherapy in patients with prostate cancer (PATRIOT): A phase 2 randomized trial

Prostate stereotactic body radiotherapy (SBRT) regimens differ in time, dose, and fractionation. We completed a multicentre, randomized phase II study to investigate the impact of overall treatment time on quality of life (QOL).

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Roles of the apparent diffusion coefficient and tumor volume in predicting tumor grade in patients with choroid plexus tumors

Abstract

Purpose

To explore the utility of the apparent diffusion coefficient (ADC) and tumor volume to predict histological grade and prognosis in patients with choroid plexus tumors.

Methods

ADC and tumor volumes were retrospectively evaluated in 25 patients with choroid plexus papilloma (CPP; WHO grade 1 [n = 13]), atypical CPP (aCPP; grade 2 [n = 8]), or choroid plexus carcinoma (grade 3 [n = 4]) The prognostic roles of ADC and tumor volume were assessed.

Results

There were significant differences in mean and minimum ADC values, and tumor volume among the WHO grades (p = 0.033, p = 0.044, and p = 0.014, respectively). Receiver-operating characteristic analysis revealed a mean cutoff ADC value ≤ 1.397 × 10−3 mm2/s for aCPP (sensitivity = 0.667, specificity = 0.923). Multiple linear regression analysis demonstrated that both mean ADC (β = − 0.455, p = 0.005) and tumor volume (β = 0.513, p = 0.002) were correlated with WHO grade (adjusted R2 = 0.520, p = 0.005). Kaplan-Meier curve analysis identified poorer survival in patients with WHO grade 2 and 3 tumors than in those with WHO grade 1 disease (p = 0.049 and p = 0.012, respectively). A mean ADC ≤ 1.397 × 10−3 mm2/s (p = 0.001) and tumor volume 21.05 ml (p = 0.031) predicted significantly poorer survival.

Conclusion

Mean ADC and tumor volume were correlated with WHO grade of choroid plexus tumors. A lower ADC value and a larger tumor volume predicted a poorer prognosis.



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Roles of the apparent diffusion coefficient and tumor volume in predicting tumor grade in patients with choroid plexus tumors

Abstract

Purpose

To explore the utility of the apparent diffusion coefficient (ADC) and tumor volume to predict histological grade and prognosis in patients with choroid plexus tumors.

Methods

ADC and tumor volumes were retrospectively evaluated in 25 patients with choroid plexus papilloma (CPP; WHO grade 1 [n = 13]), atypical CPP (aCPP; grade 2 [n = 8]), or choroid plexus carcinoma (grade 3 [n = 4]) The prognostic roles of ADC and tumor volume were assessed.

Results

There were significant differences in mean and minimum ADC values, and tumor volume among the WHO grades (p = 0.033, p = 0.044, and p = 0.014, respectively). Receiver-operating characteristic analysis revealed a mean cutoff ADC value ≤ 1.397 × 10−3 mm2/s for aCPP (sensitivity = 0.667, specificity = 0.923). Multiple linear regression analysis demonstrated that both mean ADC (β = − 0.455, p = 0.005) and tumor volume (β = 0.513, p = 0.002) were correlated with WHO grade (adjusted R2 = 0.520, p = 0.005). Kaplan-Meier curve analysis identified poorer survival in patients with WHO grade 2 and 3 tumors than in those with WHO grade 1 disease (p = 0.049 and p = 0.012, respectively). A mean ADC ≤ 1.397 × 10−3 mm2/s (p = 0.001) and tumor volume 21.05 ml (p = 0.031) predicted significantly poorer survival.

Conclusion

Mean ADC and tumor volume were correlated with WHO grade of choroid plexus tumors. A lower ADC value and a larger tumor volume predicted a poorer prognosis.



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The future of Radiology augmented with Artificial Intelligence: a strategy for success

Publication date: Available online 14 March 2018
Source:European Journal of Radiology
Author(s): Charlene Liew
The rapid development of artificial intelligence/deep learning technology and its implementation into routine clinical imaging will cause a major transformation to the practice of radiology. Strategic positioning will ensure the successful transition of radiologists into their new roles as augmented clinicians. This paper describes an overall vision on how to achieve a smooth transition through the practice of augmented radiology where radiologists-in-the-loop ensure the safe implementation of artificial intelligence systems.



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Vascular CT and MRI: a practical guide to imaging protocols

Abstract

Non-invasive cross-sectional imaging techniques play a crucial role in the assessment of the varied manifestations of vascular disease. Vascular imaging encompasses a wide variety of pathology. Designing vascular imaging protocols can be challenging owing to the non-uniform velocity of blood in the aorta, differences in cardiac output between patients, and the effect of different disease states on blood flow. In this review, we provide the rationale behind—and a practical guide to—designing and implementing straightforward vascular computed tomography (CT) and magnetic resonance imaging (MRI) protocols.

Teaching Points

• There is a wide range of vascular pathologies requiring bespoke imaging protocols.

• Variations in cardiac output and non-uniform blood velocity complicate vascular imaging.

• Contrast media dose, injection rate and duration affect arterial enhancement in CTA.

• Iterative CT reconstruction can improve image quality and reduce radiation dose.

• MRA is of particular value when imaging small arteries and venous studies.



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Paradigm shift in theranostics of neuroendocrine tumors: conceptual horizons of nanotechnology in nuclear medicine

Abstract

We present a comprehensive review of Neuroendocrine Tumors (NET) and the current and developing imaging and therapeutic modalities for NET with emphasis on Nuclear Medicine modalities. Subsequently, nanotechnology and its emerging role in cancer management, especially NET, are discussed. The article is both educative and informative. The objective is to provide an insight into the developments made in nuclear medicine and nanotechnology towards management of NET, individually as well as combined together.



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Relationship between collateral circulation and myocardial viability of 18 F-FDG PET/CT subtended by chronic total occluded coronary arteries

Abstract

Objective

To analyze the relationship between the collateral flow of coronary chronic total occlusion (CTO) and myocardial viability detected by 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) imaging.

Methods

A prospective analysis of 104 patients diagnosed by coronary angiography. All patients underwent resting myocardial perfusion imaging and PET/CT within 1 week. The collateral circulation was graded with Rentrop classification as no or poor collateral circulation in 16 CTO vessels, moderate collateral circulation in 34 CTO vessels, and good collateral circulation in 69 CTO vessels. Myocardial viability was determined with myocardial perfusion imaging and PET. The patterns were interpreted as mismatch, match and normal perfusion and 18F-FDG uptake.

Results

There was no significant correlation between the severity and extent of perfusion defect, myocardial viability and collateral circulation grade. The myocardial viability was normal in mild and moderate hypokinetic regions and decreased in severe hypokinetic and akinesis–dyskinesis regions. The presence of collateral circulation was a sensitive (89%) but not a specific (31%) sign of myocardial viability.

Conclusions

In patients with CTO, collateral circulation does not seem to be an effective way for predicting myocardial viability. Further analysis of PET patterns of viable myocardium is needed to guide further revascularization and predict functional improvement and survival benefit.



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Automated segmentation and detection of increased uptake regions in bone scintigraphy using SPECT/CT images

Abstract

Purpose

To develop a method for automated detection of highly integrated sites in SPECT images using bone information obtained from CT images in bone scintigraphy.

Methods

Bone regions on CT images were first extracted, and bones were identified by segmenting multiple regions. Next, regions corresponding to the bone regions on SPECT images were extracted based on the bone regions on CT images. Subsequently, increased uptake regions were extracted from the SPECT image using thresholding and three-dimensional labeling. Last, the ratio of increased uptake regions to all bone regions was calculated and expressed as a quantitative index. To verify the efficacy of this method, a basic assessment was performed using phantom and clinical data.

Results

The results of this analytical method using phantoms created by changing the radioactive concentrations indicated that regions of increased uptake were detected regardless of the radioactive concentration. Assessments using clinical data indicated that detection sensitivity for increased uptake regions was 71% and that the correlation between manual measurements and automated measurements was significant (correlation coefficient 0.868).

Conclusion

These results suggested that automated detection of increased uptake regions on SPECT images using bone information obtained from CT images would be possible.



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Improvement in the measurement error of the specific binding ratio in dopamine transporter SPECT imaging due to exclusion of the cerebrospinal fluid fraction using the threshold of voxel RI count

Abstract

Objective

In Japan, the Southampton method for dopamine transporter (DAT) SPECT is widely used to quantitatively evaluate striatal radioactivity. The specific binding ratio (SBR) is the ratio of specific to non-specific binding observed after placing pentagonal striatal voxels of interest (VOIs) as references. Although the method can reduce the partial volume effect, the SBR may fluctuate due to the presence of low-count areas of cerebrospinal fluid (CSF), caused by brain atrophy, in the striatal VOIs. We examined the effect of the exclusion of low-count VOIs on SBR measurement.

Methods

We retrospectively reviewed DAT imaging of 36 patients with parkinsonian syndromes performed after injection of 123I-FP-CIT. SPECT data were reconstructed using three conditions. We defined the CSF area in each SPECT image after segmenting the brain tissues. A merged image of gray and white matter images was constructed from each patient's magnetic resonance imaging (MRI) to create an idealized brain image that excluded the CSF fraction (MRI-mask method). We calculated the SBR and asymmetric index (AI) in the MRI-mask method for each reconstruction condition. We then calculated the mean and standard deviation (SD) of voxel RI counts in the reference VOI without the striatal VOIs in each image, and determined the SBR by excluding the low-count pixels (threshold method) using five thresholds: mean-0.0SD, mean-0.5SD, mean-1.0SD, mean-1.5SD, and mean-2.0SD. We also calculated the AIs from the SBRs measured using the threshold method. We examined the correlation among the SBRs of the threshold method, between the uncorrected SBRs and the SBRs of the MRI-mask method, and between the uncorrected AIs and the AIs of the MRI-mask method.

Results

The intraclass correlation coefficient indicated an extremely high correlation among the SBRs and among the AIs of the MRI-mask and threshold methods at thresholds between mean-2.0D and mean-1.0SD, regardless of the reconstruction correction. The differences among the SBRs and the AIs of the two methods were smallest at thresholds between man-2.0SD and mean-1.0SD.

Conclusion

The SBR calculated using the threshold method was highly correlated with the MRI–SBR. These results suggest that the CSF correction of the threshold method is effective for the calculation of idealized SBR and AI values.



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Coefficient of variation on Gd-EOB MR imaging: Correlation with the presence of early-stage hepatocellular carcinoma in patients with chronic hepatitis B

Publication date: May 2018
Source:European Journal of Radiology, Volume 102
Author(s): Jung Hun Lee, Youe Ree Kim, Guy Mok Lee, Jong Hyun Ryu, Eun Young Cho, Young Hwan Lee, Kwon-Ha Yoon
PurposeTo study whether the measurement of hepatic fibrosis on gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA) magnetic resonance (MR) imaging using the coefficient of variation (CV) might be correlated with the presence of hepatocellular carcinoma (HCC) in patients with chronic hepatitis B (CHB).Materials and methodsThis study included 104 patients with and without CHB, who were divided into 4 groups: control group, CHB without liver cirrhosis (LC; Group I), CHB with LC (Group II), and CHB with LC and HCC (Group III). MR images were analyzed to measure the inhomogeneity of signal intensities calculated using the CV map of the liver parenchyma. Intergroup comparisons of CV values were performed using ANOVA. The diagnostic performance of the CV map and alpha-fetoprotein (AFP) for diagnosing HCC was evaluated using the receiver operating characteristic (ROC) curve.ResultsOn the hepatobiliary phase of Gd-EOB-DTPA-enhanced T1-weighted imaging, the mean CV values of the control group and Groups I, II, and III were 3.9 ± 0.99, 3.97 ± 1.09, 5.58 ± 2.05, and 6.80 ± 2.34, respectively (P = 0.000). On ROC analysis of the CV value for predicting HCC, the value of the area under the curve (AUC) on Gd-EOB-DTPA MR imaging was 0.788 (95% CI: 0.697-0.862). The sensitivity and specificity were 84.2% and 63.6%, respectively, at a CV cutoff value >4.75. The value of AUC determined using AFP was 0.766.ConclusionThe CV value for hepatic fibrosis on Gd-EOB-DTPA MR imaging may be correlated with the presence of HCC in patients with CHB, and shows comparable diagnostic performance to AFP analysis.



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IMAGING OF ADULT OBSTRUCTIVE SLEEP APNOEA

Publication date: Available online 13 March 2018
Source:European Journal of Radiology
Author(s): Andy Whytec, Daren Gibson
Obstructive sleep apnoea (OSA) is characterised by recurrent upper airway collapse during sleep resulting in chronic and repetitive hypoxia, hypercapnia, subsequent arousal and fragmented sleep. Symptoms are insidious and diagnosis is usually delayed. Moderate to severe OSA has serious health implications with significant increase in all causes of mortality in patients with the condition as compared with unaffected individuals. The prevalence of OSA in the 30–70 year age group is estimated at 27% of males and 11% of females and it increases with age. 80% of affected individuals are obese and as obesity rates rise, so has the prevalence of OSA. An overnight polysomnogram (PSG) is required for a definitive diagnosis of OSA. Imaging has played a fundamental role in the evaluation of the anatomical factors associated with recurrent upper airway collapse and the pathogenesis of OSA. The upper airway is frequently imaged by radiologists, providing an opportunity to detect features that are strongly associated with unsuspected OSA and to raise the possibility of this diagnosis. The gold standard of treatment is continuous positive airway pressure (CPAP) which acts as a pneumatic splint for the upper airway. However, efficacy is frequently limited by poor tolerance; clinicians and patients are increasingly opting for one of a range of surgical procedures. Dedicated imaging protocols can be performed for evaluation of the upper airway to aid surgical planning.



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Rapid switching kVp dual energy CT: Value of reconstructed dual energy CT images and organ dose assessment in multiphasic liver CT exams

Publication date: May 2018
Source:European Journal of Radiology, Volume 102
Author(s): Usman Mahmood, Natally Horvat, Joao Vicente Horvat, Davinia Ryan, Yiming Gao, Gabriella Carollo, Rommel DeOcampo, Richard K. Do, Seth Katz, Scott Gerst, C. Ross Schmidtlein, Lawrence Dauer, Yusuf Erdi, Lorenzo Mannelli
PurposeClinical applications of dual energy computed tomography (DECT) have been widely reported; however, the importance of the different image reconstructions and radiation organ dose remains a relevant area of investigation, particularly considering the different commercially available DECT equipment. Therefore, the purpose of this study was to assess the image reliability and compare the information content between several image reconstructions in a rapid-switching DECT (rsDECT), and assess radiation organ dose between rsDECT and conventional single-energy computed tomography (SECT) exams.Materials and methodsThis Institutional Review Board-approved retrospective study included 98 consecutive patients who had a history of liver cancer and underwent multiphasic liver CT exams with rsDECT applied during the late arterial phase between June 2015 and December 2015. Virtual monochromatic 70 keV, material density images (MDI) iodine (-water) and virtual unenhanced (VUE) images were generated. Radiation dose analysis was performed in a subset of 44 patients who had also undergone a multiphasic SECT examination within 6 months of the rsDECT. Four board-certified abdominal radiologists reviewed 24–25 patients each, and a fifth radiologist re-evaluated all the scans to reach a consensus. The following imaging aspects were assessed by the radiologists: (a) attenuation measurements were made in the liver and spleen in VUE and true unenhanced (TUE) images; (b) subjective evaluation for lesion detection and conspicuity on MDI iodine (-water)/VUE images compared with the virtual monochromatic images/TUE images; and (c) overall image quality using a five-point Likert scale. The radiation dose analyses were evaluated in the subset of 44 patients regarding the following parameters: CTDIvol, dose length product, patient's effective diameter and organ dose using a Monte Carlo-based software, VirtualDose™ (Virtual Phantoms, Inc.) to 21 organs.ResultsOn average, image noise on the TUE images was 49% higher within the liver (p < 0.0001) and 48% higher within the spleen (p < 0.0001). CT numbers for the spleen were significantly higher on VUE images (p < 0.0001). Twenty-eight lesions in 24/98 (24.5%) patients were not observed on the VUE images. The conspicuity of vascular anatomy was considered better on MDI iodine (-water) Images 26.5% of patients. Using the Likert scale, the rsDECT image quality was considered to be satisfactory. Considering the subset of 44 patients with recent SECT, the organ dose was, on average, 37.4% less with rsDECT. As the patient's effective diameter decreased, the differences in dose between the rsDECT and SECT increased, with the total average organ dose being less by 65.1% when rsDECT was used.ConclusionVUE images in the population had lower image noise than TUE images; however, a few small and hyperdense findings were not characterized on VUE images. Delineation of vascular anatomy was considered better in around a quarter of patients on MDI iodine (-water) images. Finally, radiation dose, particularly organ dose, was found to be lower with rsDECT, especially in smaller patients.



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Survival of patients with non-resectable, chemotherapy-resistant colorectal cancer liver metastases undergoing conventional lipiodol-based transarterial chemoembolization (cTACE) palliatively versus neoadjuvantly prior to percutaneous thermal ablation

Publication date: Available online 14 March 2018
Source:European Journal of Radiology
Author(s): Thomas J. Vogl, Maximilian Lahrsow, Moritz H. Albrecht, Renate Hammerstingl, Zachary M. Thompson, Tatjana Gruber-Rouh
PurposeTo determine overall (OS) and progression-free survival (PFS) for cTACE alone and in combination with percutaneous thermal ablation in patients with non-resectable, chemotherapy-resistant colorectal cancer liver metastases (CRLM).Material and methodsThe study included 452 patients undergoing 2654 repetitive cTACE treatments of CRLM. 233 patients were treated palliatively using only cTACE, whereas 219 patients were treated with cTACE in a neoadjuvant intend with subsequent thermal ablation (either microwave ablation or laser-induced thermotherapy). The chemotherapeutics agents used, in either single-, double-, or triple-combinations, included MitomycinC, Gemcitabine, Irinotecan, and Cisplatin. Several factors were analysed to determine their prognostic value in terms of OS and PFS.ResultsPalliative use of cTACE resulted in a median OS and PFS of 12.6 and 5.9 months, whereas the neoadjuvant use of cTACE showed a median OS and PFS of 25.8 and 10.8 months. The differences in OS and PFS between the two groups were statistically significant (p < 0.001).Extrahepatic metastases were a significant prognostic factor in the OS and PFS analysis of the palliative and neoadjuvant group. In addition, number, location, and mean size of metastases were significant prognostic factors for OS and PFS in the neoadjuvant group. Sex, primary tumor location, T- and N-parameters of the TNM staging system, time of liver metastases appearance, ablation method, and patient age did not significantly impact OS and PFS in either patient group. The most distinct response to cTACE was observed in metastases that were treated with a triple-combination of chemotherapeutics (p = 0.021).ConclusioncTACE is an effective treatment option in advanced non-resectable CRLM. Chemoembolization followed by ablation further increases survival rates. A triple combination of chemotherapeutics improves response to cTACE.



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A Subjective and Objective Comparison of Tissue Contrast and Imaging Artifacts Present in Routine Spin Echoes and in Iterative Decomposition of Asymmetric Spin Echoes for Soft Tissue Neck MRI

Publication date: Available online 14 March 2018
Source:European Journal of Radiology
Author(s): Subhendra N. Sarkar, David B. Hackney, Robert L. Greenman, Behroze A. Vachha, Emelia A. Johnson, Sue Nagle, Gul Moonis
ObjectiveFSE sequences play key roles in neck MRI despite the susceptibility issues in neck region. Iterative decomposition of asymmetric echoes (IDEAL, GE) is a promising method that separates fat and water images resulting in high SNR and improved fat suppression. We tested how neck tissue contrasts, image artifacts and fat separation as opposed to fat suppression in terms of image quality compare between routine and IDEAL FSE.MethodsIDEAL based and routine T1 and T2-weighted FSE sequences were applied for neck MRI at 1.5T and 3T. Overall image quality including fat suppression, tissue contrast, image artifacts and lesion conspicuity were subjectively assessed for 20 patients clinically indicated for neck MRI. Quantitative tissue contrast estimates from parotid area were compared between IDEAL and routine FSE for 7 patients. Four patients with oncocytoma were also reviewed to assess benefits of separately reconstructed fat specific image sets.ResultsSubjective tissue contrast and overall image quality including image sharpness, fat suppression and image artifacts were superior for IDEAL sequences. For oncocytoma fat specific IDEAL images provided additional information.ObjectiveCNR estimates from a central slice were equivalent for IDEAL and routine FSE at both field strengths.ConclusionsWe demonstrated that high SNR inherent in IDEAL FSE consistently translates into high tissue contrast with image quality advantages in neck anatomy where large susceptibility variation and physiological motions reduce image quality for conventional FSE T1 and T2. However, the objective contrast estimates for parotid gland at isocenter were statistically equivalent for IDEAL and conventional FSE perhaps because at or near isocenter routine FSE works well. Additionally, fat specific IDEAL image sets add to diagnostic specificity for fat deficient lesions.



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Survey Result of the Counting Efficiency of Gamma Counter by Certified Reference Materials

Abstract

Purpose

In radioimmunoassay (RIA), the gamma counter is the important instrument for the accurate measurement. To manage quality assurance of RIA, the counting efficiency of gamma counter is one of the important parameters. The aim of this study was to evaluate the counting efficiency of gamma counters in multiple institutes on the base of traceability by using the certified reference materials (CRMs).

Methods

Twenty-three institutes that perform RIA were enrolled in this study. I-125 CRMs that were certified by National Institute of Standards and Technology (NIST) were used. Each institute was asked to count the activity of I-125 CRMs at most twice on all gamma counters in use. The counting efficiency of each well of counter was calculated on the base of NIST-certified information, corrected for I-125 decay for date of testing.

Results

From 23 institutes, 44 gamma counters were evaluated. The average counting efficiency of all wells was 85.9% and the standard deviation was 13.5%. As a mean value of each gamma counter, three gamma counters showed poor counting efficiency (less than 70%). The poorest counting efficiency was 7%. The counting efficiency of seven gamma counters was between 70 and 75%. Eight counters had the counting efficiency between 75 and 90%. More than half of counter (26 gamma counters) showed excellent counting efficiency (more than 90%). The standard deviation variation range of inter-well efficiency was from 0 to 11.2.

Conclusion

The first survey on the counting efficiency of gamma counter was performed in South Korea. Most of the RIA laboratories have well managed the quality assurance of gamma counter.



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Retrieval and registration of long-range overlapping frames for scalable mosaicking of in vivo fetoscopy

Abstract

Purpose

The standard clinical treatment of Twin-to-Twin transfusion syndrome consists in the photo-coagulation of undesired anastomoses located on the placenta which are responsible to a blood transfer between the two twins. While being the standard of care procedure, fetoscopy suffers from a limited field-of-view of the placenta resulting in missed anastomoses. To facilitate the task of the clinician, building a global map of the placenta providing a larger overview of the vascular network is highly desired.

Methods

To overcome the challenging visual conditions inherent to in vivo sequences (low contrast, obstructions or presence of artifacts, among others), we propose the following contributions: (1) robust pairwise registration is achieved by aligning the orientation of the image gradients, and (2) difficulties regarding long-range consistency (e.g. due to the presence of outliers) is tackled via a bag-of-word strategy, which identifies overlapping frames of the sequence to be registered regardless of their respective location in time.

Results

In addition to visual difficulties, in vivo sequences are characterised by the intrinsic absence of gold standard. We present mosaics motivating qualitatively our methodological choices and demonstrating their promising aspect. We also demonstrate semi-quantitatively, via visual inspection of registration results, the efficacy of our registration approach in comparison with two standard baselines.

Conclusion

This paper proposes the first approach for the construction of mosaics of placenta in in vivo fetoscopy sequences. Robustness to visual challenges during registration and long-range temporal consistency are proposed, offering first positive results on in vivo data for which standard mosaicking techniques are not applicable.



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Trackerless panoramic optoacoustic imaging: a first feasibility evaluation

Abstract

Purpose

Optoacoustic imaging provides high spatial resolution and the possibility to image specific functional parameters in real-time, therefore positioning itself as a promising modality for various applications. However, despite these advantages, the applicability of real-time optoacoustic imaging is generally limited due to a relatively small field of view.

Methods

With this work, we aim at presenting a path towards panoramic optoacoustic tomographic imaging without requiring additional sensors or position trackers. We propose a two-step seamless stitching method for the compounding of multiple datasets acquired with a real-time 3D optoacoustic imaging system within a panoramic scan. The employed workflow is specifically tailored to the image properties and respective challenges.

Results

A comparison of the presented alignment on in-vivo data shows a mean error of \(628 \pm 512\,\upmu \hbox {m}\) compared to ground truth tracking data. The presented compounding scheme integrates the physical resolution of optoacoustic data and hence can provide improved contrast in comparison with other compounding approaches based on addition or averaging.

Conclusion

The proposed method can produce optoacoustic volumes with an enlarged field of view and improved quality compared to current methods in optoacoustic imaging. However, our study also shows challenges for panoramic scans. In this view, we discuss relevant properties, challenges, and opportunities and present an evaluation of the performance of the presented approach with different input data.



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Fully automatic detection of renal cysts in abdominal CT scans

Abstract

Purpose

Simple renal cysts are a common benign finding in abdominal CT scans. However, since they may evolve in time, simple cysts need to be reported. With an ever-growing number of slices per CT scan, cysts are easily overlooked by the overloaded radiologist. In this paper, we address the detection of simple renal cysts as an incidental finding in a real clinical setting.

Methods

We propose a fully automatic framework for renal cyst detection, supported by a robust segmentation of the kidneys performed by a fully convolutional neural network. A combined 3D distance map of the kidneys and surrounding fluids provides initial candidates for cysts. Eventually, a second convolutional neural network classifies the candidates as cysts or non-cyst objects.

Results

Performance was evaluated on 52 abdominal CT scans selected at random in a real radiological workflow and containing over 70 cysts annotated by an experienced radiologist. Setting the minimal cyst diameter to 10 mm, the algorithm detected 59/70 cysts (true-positive rate = 84.3%) while producing an average of 1.6 false-positive per case.

Conclusions

The obtained results suggest the proposed framework is a promising approach for the automatic detection of renal cysts as incidental findings of abdominal CT scans.



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Evaluation of cone-beam computed tomography diagnostic image quality using cluster signal-to-noise analysis

Abstract

Objectives

(1) We sought to assess correlation among four representative parameters from a cluster signal-to-noise curve (true-positive rate [TPR] corresponding to background noise, accuracy corresponding to background noise, maximum TPR, and maximum accuracy) and the diagnostic accuracy of the identification of the mandibular canal using data from observers in a previous study, under the same exposure conditions. (2) We sought to clarify the relationship between the hole depths of a phantom and diagnostic accuracy.

Methods

CBCT images of a Teflon plate phantom with holes of decreasing depths from 0.7 to 0.1 mm were analyzed using the FindFoci plugin of ImageJ. Subsequently, we constructed cluster signal-to-noise curves by plotting TPRs against false-positive rates. The four parameters were assessed by comparing with the diagnostic accuracy calculated from the observers. To analyze image contrast ranges related to detection of mandibular canals, we determined five ranges of hole depths, to represent different contrast ranges—0.1–0.7, 0.1–0.5, 0.2–0.6, 0.2–0.7 and 0.3–0.7 mm—and compared them with observers' diagnostic accuracy.

Results

Among the four representative parameters, accuracy corresponding to background noise had the highest correlation with the observers' diagnostic accuracy. Hole depths of 0.3–0.7 and 0.1–0.7 mm had the highest correlation with observers' diagnostic accuracy in mandibles with distinct and indistinct mandibular canals, respectively.

Conclusions

The accuracy corresponding to background noise obtained from the cluster signal-to-noise curve can be used to evaluate the effects of exposure conditions on diagnostic accuracy.



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Educational Assumptions

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Publication date: Available online 14 March 2018
Source:Academic Radiology
Author(s): Richard B. Gunderman




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Viewing the Value of Radiology Through Patient Web Portals

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Publication date: Available online 15 March 2018
Source:Academic Radiology
Author(s): Geraldine J. Liao, Christoph I. Lee
With widespread adoption of web portals and unfettered patient access to online radiology reports, these previous end products are quickly becoming springboards for direct radiologist-patient interactions, further increasing the value proposition for radiologists in an era of patient-centered care. Here, we provide a real-world scenario demonstrating a teachable moment on how imaging examination reporting in the digital era is expanding the radiologist's role in patient consultation.



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Typology of intravesical prostatic protrusions, or so-called median lobes, in middle-aged and older men.

Typology of intravesical prostatic protrusions, or so-called median lobes, in middle-aged and older men.

Surg Radiol Anat. 2018 Mar 13;:

Authors: Audouin M, Girshovich A, Cussenot O, Renard-Penna R

Abstract
PURPOSE: Changes related to prostatic ageing include an increase of prostate volume and morphologic distortions of the prostatic edges in middle-aged and older men. These changes of the prostate exhibit a certain level of heterogeneity, which is clinically obvious for surgeons, radiologists, and anatomists, and which can be explained by the complex nature of the embryologic/anatomic development of the prostate. While the etiology of the median lobe has typically been attributed to a growth and protrusion of the prostatic area at the top of the utricle, we argue that this is not necessarily the case as intravesical protrusions of the prostate have also been observed laterally and anteriorly to the bladder neck, suggesting the involvement of other prostatic zones, thereby highlighting the need to refine the concept of the median lobe.
MATERIAL: The current study examined a large series of 478 prostate magnetic resonance imaging scans (MRIs). Intravesical prostatic protrusions were classified, based on their topography: anterior (A), posterolateral (P), and dual (D). Data were analyzed using MedCalc®11.6.1.1.0 software. Pearson's correlations with coefficients (r) and P values were calculated for the patient's age, prostate volume, and IVPP size.
RESULTS: An intravesical prostatic protrusion was observed in 27% of cases, with type A occurring in 18% (3% isolated), type P in 96% (81% isolated), and type D in 15%.
CONCLUSION: The new insights regarding the variability in prostate anatomy will contribute to the improved management of prostate hypertrophy by radiologists and surgeons.

PMID: 29536129 [PubMed - as supplied by publisher]



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Low-Dose Radioactive Iodine Ablation Is Sufficient in Patients With Small Papillary Thyroid Cancer Having Minor Extrathyroidal Extension and Central Lymph Node Metastasis (T3 N1a): Reply.

Low-Dose Radioactive Iodine Ablation Is Sufficient in Patients With Small Papillary Thyroid Cancer Having Minor Extrathyroidal Extension and Central Lymph Node Metastasis (T3 N1a): Reply.

Clin Nucl Med. 2018 Mar 13;:

Authors: Seo M, Kim YS, Lee JC, Han MW, Kim ES, Kim KB, Park SH

PMID: 29538034 [PubMed - as supplied by publisher]



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Evolution of indeterminate hepatocellular nodules at Gd-EOB-DPTA-enhanced MRI in cirrhotic patients

Abstract

Purpose

To retrospectively analyze the evolution of indeterminate hepatocellular nodules in cirrhotic patients on serial Gd-EOB-DPTA-enhanced MRI, and to identify predictors of HCC development.

Materials and methods

This IRB approved study included 33 cirrhotic patients with 69 indeterminate hepatocellular nodules (mean diameter 1.1 cm) at baseline Gd-EOB-DPTA-enhanced MRI and a Gd-EOB-DPTA-enhanced-MRI follow-up of at least 2 years. Two radiologists evaluated size and signal intensity of each nodule at baseline and follow-up. Age, cirrhosis etiology, and HCC history were recorded. Data were compared between nodules that became HCCs at follow-up (HCC) and those that did not (no-HCC).

Results

On follow-up, 5/69 nodules became HCCs and 64/69 showed indeterminate characteristics. HCC history was more frequently found in HCCs than in no-HCCs. Age, sex, and cirrhosis etiology were not significantly different between HCCs and no-HCCs. HCCs had a significantly greater baseline diameter and increase in size than no-HCCs. Hepatobiliary phase hypointensity was significantly more common in HCCs than in no-HCCs. Multivariate regression analysis showed that increase in size (OR 10.48; sensitivity, 100%; specificity, 81.2%; p < 0.001) and hepatobiliary phase hypointensity (OR 1.02; sensitivity, 100%; specificity, 78.1%; p < 0.001) was associated with HCC development.

Conclusion

Indeterminate hepatocellular nodules at Gd-EOB-DPTA-enhanced MRI in cirrhotic patients rarely became HCCs. Hepatobiliary phase hypointensity had a weak association with HCC development.



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