Editorial Board

Publication date: July 2018
Source:Journal of Environmental Radioactivity, Volume 187





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Deposition of artificial radionuclides in sediments of Loch Etive, Scotland

Publication date: July 2018
Source:Journal of Environmental Radioactivity, Volume 187
Author(s): Hamza Al-Qasmi, Gareth T.W. Law, L. Keith Fifield, John A. Howe, Tim Brand, Gregory L. Cowie, Kathleen A. Law, Francis R. Livens
The nuclear fuel reprocessing plants on the Sellafield site (UK) have released low-level effluents into the Irish Sea under authorisation since 1952. This has led to the labelling of nearby offshore sediments with a range of artificial radionuclides. In turn, these sediments act as a long-term secondary source of both soluble and particle-associated radionuclides to coastal areas. These radionuclides are of interest both in assessing possible environmental impacts and as tracers for marine processes. Here we present results from a study of the geochemistry of natural (^{234, 238}U) and artificial (¹³⁷Cs, ²⁴¹Am, ²³⁸Pu, ^239+240Pu, and ²³⁶U) radionuclides and their accumulation in sediments from Loch Etive, Scotland. The data are interpreted in the context of the historical radioactive discharges to the Irish Sea and biogeochemical processes in marine sediments. Loch Etive is divided into two basins; a lower, seaward basin where the sedimentation rate (∼0.6 cm/yr) is about twice that of the more isolated upper basin (∼0.3 cm/yr). These accumulation rates are consistent with the broad distribution of ¹³⁷Cs in the sediment profiles which can be related to the maximum Sellafield discharges of ¹³⁷Cs in the mid-1970s and suggest that ¹³⁷Cs was mainly transported in solution to Loch Etive during that period. Enrichments of Mn, Fe, and Mo in sediment and porewater from both Loch Etive basins result from contemporary biogeochemical redox processes. Enrichments of ²³⁸U and ²³⁴U in the lower basin may be a result of the cycling of natural U. By contrast, the Sellafield-derived artificial isotope ²³⁶U does not seem to be affected by the redox-driven reactions in the lower basin. The ²³⁸Pu/^239,240Pu ratios suggest contributions from both historical Sellafield discharges and global fallout Pu. The uniform sediment distributions of Pu and Am, which do not reflect Sellafield historical discharges, suggest the existence of a homogenous secondary source. This could be the offshore 'mud patch' in the vicinity of Sellafield from which the supply of radionuclides reflects time-integrated Sellafield discharges. This source could also account for the continuing supply of Cs to Loch Etive, even after substantial reductions in discharge from the Sellafield site.



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Radiocesium migration in the litter layer of different forest types in Fukushima, Japan

Publication date: July 2018
Source:Journal of Environmental Radioactivity, Volume 187
Author(s): Momo Kurihara, Yuichi Onda, Hiroaki Kato, Nicolas Loffredo, Tetsuo Yasutaka, Frederic Coppin
Cesium-137 (¹³⁷Cs) migration in the litter layer consists of various processes, such as input via throughfall, output via litter decomposition, and input from deeper layers via soil organism activity. We conducted litter bag experiments over 2 years (December 2014–November 2016) to quantify the inputs and outputs of ¹³⁷Cs in the litter layer in a Japanese cedar plantation (Cryptomeria japonica) and a mixed broadleaf forest dominated by Quercus serrata located 40 km northwest of the Fukushima Dai-ichi Nuclear Power Plant. The experiments included four conditions, combining contaminated and non-contaminated litter and deeper layer material, and the inputs and outputs were estimated from the combination of ¹³⁷Cs increases and decreases in the litter layer under each condition. The ¹³⁷Cs dynamics differed between the two forests. In the C. japonica forest, some ¹³⁷Cs input via throughfall remained in the litter layer, and downward ¹³⁷Cs flux passed through the litter layer was 0.42 (/year).Upward flux of ¹³⁷Cs from the deeper layer was very restricted, < 0.017 (/year). In the broadleaf forest, migration of ¹³⁷Cs in throughfall into deeper layers was restricted, downward ¹³⁷Cs flux was less than 0.003 (/year).Upward input of ¹³⁷Cs from the deeper layer was prominent, 0.037 (/year). ¹³⁷Cs output via litter decomposition was observed in both forests. The flux in the C. japonica forest was slower than that in the broadleaf forest, 0.12 and 0.15 (/year), respectively.



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Updated database on natural radioactivity in building materials in Europe

Publication date: July 2018
Source:Journal of Environmental Radioactivity, Volume 187
Author(s): R. Trevisi, F. Leonardi, S. Risica, C. Nuccetelli
The paper presents the latest collection of activity concentration data of natural radionuclides (²²⁶Ra, ²³²Th and ⁴ K) in building materials. This database contains about 24200 samples of both bulk materials and their constituents (bricks, concrete, cement, aggregates) and superficial materials used in most European Union Member States and some European countries. This collection also includes radiological information about some NORM residues and by-products (by-product gypsum, metallurgical slags, fly and bottom ashes and red mud) which can be of radiological concern if recycled in building materials as secondary raw materials. Moreover, radon emanation and radon exhalation rate data are reported for bricks and concrete.



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Mixtures of tritiated water, zinc and dissolved organic carbon: Assessing interactive bioaccumulation and genotoxic effects in marine mussels, Mytilus galloprovincialis

Publication date: July 2018
Source:Journal of Environmental Radioactivity, Volume 187
Author(s): Holly B.C. Pearson, Lorna J. Dallas, Sean D.W. Comber, Charlotte B. Braungardt, Paul J. Worsfold, Awadhesh N. Jha
Release of tritium (³H) in the marine environment is of concern with respect to its potential bioaccumulation and detrimental impact on the biota. Previous studies have investigated the uptake and toxicity of this radionuclide in marine mussels, and the interaction of ³H with dissolved organic ligands and elevated temperature. However, despite the well-established view that toxicity is partly governed by chemical speciation, and that toxic effects of mixture of contaminants are not always additive, there have been no studies linking the prevailing chemistry of exposure waters with observed biological effects and tissue specific accumulation of ³H in combination with other constituents commonly found in natural waters. This study exposed the marine mussel Mytilus galloprovincialis for 14 days to mixtures of ³H (as tritiated water, HTO) and zinc (Zn) at 5 Mbq L⁻¹, and 383, 1913 and 3825 nM Zn, respectively, to investigate (a) ³H and Zn partitioning in soft tissues of mussels, and (b) DNA damage in haemocytes, determined using the single cell gel electrophoresis or the comet assay. Additionally, the extent of association of ³H with dissolved organic carbon (DOC, added as humic acid) over the exposure period was investigated in order to aid the interpretation of biological uptake and effects. Results concluded a clear antagonistic effect of Zn on ³H-induced DNA damage at all Zn concentrations used, likely explained by the importance of Zn in DNA repair enzymes. The interaction of DOC with ³H was variable, with strong ³H-DOC associations observed in the first 3 d of the experiment. The secretion of ³H-binding ligands by the mussels is suggested as a possible mechanism for early biological control of ³H toxicity. The results suggest risk assessments for radionuclides in the environment require consideration of potential mixture effects.



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AMS assessment of U-contamination of structural materials of the Garigliano NPP under decommissioning

Publication date: July 2018
Source:Journal of Environmental Radioactivity, Volume 187
Author(s): F. Terrasi, R. Buompane, A. D'Onofrio, A. Esposito, L. Gialanella, F. Marzaioli, A. Petraglia, G. Porzio, C. Sabbarese, F. Scolamacchia, C. Sirignano
The assessment of the radiological impact of decommissioning activities at a Nuclear Power Plant requires a detailed mapping of the distribution of radionuclides both in the environment surrounding the NPP and in its structural material. The detection of long-lived actinide isotopes and possibly the identification of their origin is particularly interesting and valuable if ultrasensitive measurement of the relative abundance of U isotopes is performed via Accelerator Mass Spectrometry (AMS). In this paper we present an investigation carried out on the structural materials of the Garigliano NPP aiming to determine the abundance of ^235,236,238U in the various compartments of the plant buildings under decommissioning. Since the expected values both for isotopic ratios and total U concentrations range over different orders of magnitude, we have developed a novel methodology for the measurement of ^234,235U/²³⁸U isotopic ratios in low U concentration samples. This allowed a systematic investigation of the distribution of all U isotopes in concrete and metal matrices of the NPP. The behavior of ^235,236U/²³⁸U isotopic ratios in the different compartments of the NPP is discussed. The correlation of these ratios with ⁶⁰Co and ¹³⁷Cs specific activities is also studied to show a different behavior for concrete and metal samples. These data represent a very valuable information to direct the decommissioning procedures under course.



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Congenital Aqueductal Stenosis: Findings at Fetal MRI That Accurately Predict a Postnatal Diagnosis [PEDIATRICS]

BACKGROUND AND PURPOSE:

Congenital aqueductal stenosis is a common cause of prenatal ventriculomegaly. An accurate diagnosis provides prognostic information and may guide obstetric management. The purpose of this study was to identify specific anatomic findings on prenatal MR imaging that can be used as predictors of congenital aqueductal stenosis.

MATERIALS AND METHODS:

Prenatal and postnatal MRIs of fetuses referred to our institution for ventriculomegaly between June 2008 and August 2015 were reviewed. Imaging findings in postnatally confirmed congenital aqueductal stenosis (disease group) were compared with those of ventriculomegaly cases from other causes (control group). Univariate analysis was performed using the Fisher exact test and the Wilcoxon rank test, and multivariate analysis, via the random forest method.

RESULTS:

Forty-three cases of ventriculomegaly had a confirmed postnatal diagnosis of congenital aqueductal stenosis. Thirty-two ventriculomegaly cases negative for congenital aqueductal stenosis were included in the control group. Dominant findings associated with an accurate prenatal diagnosis of congenital aqueductal stenosis on multivariate analysis included the following: enlarged inferior third ventricular recesses, enlargement of the lateral ventricles and third ventricle, and an abnormal corpus callosum. Findings that significantly increase the probability of congenital aqueductal stenosis (high positive predictive value) included the following: enlarged third ventricular recesses, aqueduct funneling, hemorrhage in the cerebral aqueduct, ventricular diverticulum, rhombencephalosynapsis, and dystroglycanopathy-related cerebellar dysplasia.

CONCLUSIONS:

Our study identified specific characteristics on fetal MR imaging that can be used as predictors of the diagnosis of congenital aqueductal stenosis. Most of these findings are secondary to the obstructive nature of the resulting hydrocephalus. Common associated malformations such as rhombencephalosynapsis and dystroglycanopathies should also increase the suspicion of congenital aqueductal stenosis when present with ventriculomegaly.

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Prenatal Brain MR Imaging: Reference Linear Biometric Centiles between 20 and 24 Gestational Weeks [PEDIATRICS]

BACKGROUND AND PURPOSE:

Evaluation of biometry is a fundamental step in prenatal brain MR imaging. While different studies have reported reference centiles for MR imaging biometric data of fetuses in the late second and third trimesters of gestation, no one has reported them in fetuses in the early second trimester. We report centiles of normal MR imaging linear biometric data of a large cohort of fetal brains within 24 weeks of gestation.

MATERIALS AND METHODS:

From the data bases of 2 referral centers of fetal medicine, accounting for 3850 examinations, we retrospectively collected 169 prenatal brain MR imaging examinations of singleton pregnancies, between 20 and 24 weeks of gestational age, with normal brain anatomy at MR imaging and normal postnatal neurologic development. To trace the reference centiles, we used the CG-LMS method.

RESULTS:

Reference biometric centiles for the developing structures of the cerebrum, cerebellum, brain stem, and theca were obtained. The overall interassessor agreement was adequate for all measurements.

CONCLUSIONS:

Reference biometric centiles of the brain structures in fetuses between 20 and 24 weeks of gestational age may be a reliable tool in assessing fetal brain development.

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Fast and Robust Unsupervised Identification of MS Lesion Change Using the Statistical Detection of Changes Algorithm [ADULT BRAIN]

SUMMARY:

We developed a robust automated algorithm called statistical detection of changes for detecting morphologic changes of multiple sclerosis lesions between 2 T2-weighted FLAIR brain images. Results from 30 patients showed that statistical detection of changes achieved significantly higher sensitivity and specificity (0.964, 95% CI, 0.823–0.994; 0.691, 95% CI, 0.612–0.761) than with the lesion-prediction algorithm (0.614, 95% CI, 0.410–0.784; 0.281, 95% CI, 0.228–0.314), while resulting in a 49% reduction in human review time (P = .007).

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Long-Term Outcomes of Patients with Stent Tips Embedded into Internal Carotid Artery Branches during Aneurysm Coiling [INTERVENTIONAL]

BACKGROUND AND PURPOSE:

During stent-assisted coiling of ICA aneurysms, stent tips are sometimes unintentionally embedded into ICA branches. Stent tips can be visualized because they have radiopaque markers. Concerns regarding stent tip misplacement include risks of artery perforation and occlusion. The aim of this study was to evaluate the long-term outcomes of ICA branches with embedded stent tips.

MATERIALS AND METHODS:

ICA branches with embedded stent tips were identified among 35 patients with unruptured ICA aneurysms treated with stent-assisted coiling between November 2003 and November 2014. Patient clinical and angiographic outcomes associated with the embedded stent tip were analyzed.

RESULTS:

Most of the 35 studied aneurysms were paraclinoid ICA aneurysms (n = 30). The most commonly involved ICA branch was the posterior communicating artery (26 patients, 74.3%), followed by the anterior choroidal artery (8 patients, 22.9%) and ophthalmic artery (1 patient, 2.9%). During the follow-up period (38.6 ± 17.9 months), no new neurologic deficits developed. Neither hemorrhagic nor thromboembolic events occurred. Angiography was performed during the final follow-up evaluation at a mean of 32.7 ± 18.0 months, and all ICA branches with embedded stent tips showed patent blood flow without severe luminal narrowing.

CONCLUSIONS:

In our experience, placement of a stent tip into ICA branches during stent-assisted coiling was not associated with any major adverse events.

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MRI Features Can Predict 1p/19q Status in Intracranial Gliomas [ADULT BRAIN]

BACKGROUND AND PURPOSE:

The 2016 revision of the World Health Organization Classification of Tumors of the Central Nervous System mandates codeletion of chromosomes 1p and 19q for the diagnosis of oligodendroglioma. We studied whether conventional MR imaging features could predict 1p/19q status.

MATERIALS AND METHODS:

Patients with previous 1p/19q testing were identified through pathology department records, typically performed on the basis of an oligodendroglial component on routine histology; 69 patients met the inclusion criteria. Preoperative imaging of patients with grade II or III gliomas was retrospectively assessed by 2 neuroradiologists, blinded to the 1p/19q status. Thirteen MR imaging features were first assessed in a small initial cohort (n = 10), after which the criteria were narrowed for the remaining patients as a validation cohort.

RESULTS:

There was 85% agreement between radiologists for the overall prediction of 1p/19q status in the validation cohort, with an accuracy of 84%. The presence of >50% T2-FLAIR mismatch and calcification was found to be the most useful for predicting 1p/19q status. The >50% T2-FLAIR mismatch variable was demonstrated in 14 tumors and had 100% specificity for identifying a noncodeleted tumor (P = .001), with 97% interobserver correlation. Calcification was visualized in 7 tumors, 6 of which were 1p/19q codeleted (specificity, 97%; P = .006), with 100% interobserver correlation.

CONCLUSIONS:

The presence of >50% T2-FLAIR mismatch is highly predictive of a noncodeleted tumor, while calcifications suggest a 1p/19q codeleted tumor. If formal 1p/19q testing is not possible, a combined MR imaging–histologic assessment may improve the diagnostic accuracy over histology alone.

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Quantitative Phase-Contrast MR Angiography to Measure Hemodynamic Changes in Idiopathic Intracranial Hypertension [ADULT BRAIN]

BACKGROUND AND PURPOSE:

Idiopathic intracranial hypertension is a syndrome of raised intracranial pressure of unknown etiology. Few MR imaging–based studies have investigated arterial and venous blood flow in these patients. Results are inconclusive, and to our knowledge, no comparison of the hemodynamic parameters before and after CSF pressure reduction has been published. The aim of this study was to assess the short-term effects of normalizing CSF pressure on intracranial flow to better understand the pathophysiology of idiopathic intracranial hypertension.

MATERIALS AND METHODS:

In this study, we performed quantitative MR imaging–derived flow measurements of brain-supplying arteries and draining veins/dural sinuses to visualize hemodynamic changes in patients with idiopathic intracranial hypertension before and after therapy by lumbar puncture in comparison with a healthy control group.

RESULTS:

We found differences in patients before and after lumbar puncture in the calculated resistance and pulsatility indices in the superior sagittal sinus. Venous pulsatility showed a negative correlation with CSF pressure in untreated patients. Additionally, there was a trend toward lower flow in the superior sagittal sinus in patients compared with healthy controls. Flow in the internal jugular veins was significantly reduced by lumbar puncture, and the resistance and pulsatility indices differed in patients and controls. The arterial flow was not influenced by pressure normalization.

CONCLUSIONS:

The results of the present study indicate that venous but not arterial blood flow differs in patients compared with controls and that calculating resistance and pulsatility indices may contribute to assessing short-term hemodynamic changes in patients with diagnosed idiopathic intracranial hypertension before and after CSF diversion.

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Whole-Tumor Histogram and Texture Analyses of DTI for Evaluation of IDH1-Mutation and 1p/19q-Codeletion Status in World Health Organization Grade II Gliomas [ADULT BRAIN]

BACKGROUND AND PURPOSE:

Prediction of the isocitrate dehydrogenase 1 (IDH1)-mutation and 1p/19q-codeletion status of World Health Organization grade ll gliomas preoperatively may assist in predicting prognosis and planning treatment strategies. Our aim was to characterize the histogram and texture analyses of apparent diffusion coefficient and fractional anisotropy maps to determine IDH1-mutation and 1p/19q-codeletion status in World Health Organization grade II gliomas.

MATERIALS AND METHODS:

Ninety-three patients with World Health Organization grade II gliomas with known IDH1-mutation and 1p/19q-codeletion status (18 IDH1 wild-type, 45 IDH1 mutant and no 1p/19q codeletion, 30 IDH1-mutant and 1p/19q codeleted tumors) underwent DTI. ROIs were drawn on every section of the T2-weighted images and transferred to the ADC and the fractional anisotropy maps to derive volume-based data of the entire tumor. Histogram and texture analyses were correlated with the IDH1-mutation and 1p/19q-codeletion status. The predictive powers of imaging features for IDH1 wild-type tumors and 1p/19q-codeletion status in IDH1-mutant subgroups were evaluated using the least absolute shrinkage and selection operator.

RESULTS:

Various histogram and texture parameters differed significantly according to IDH1-mutation and 1p/19q-codeletion status. The skewness and energy of ADC, 10th and 25th percentiles, and correlation of fractional anisotropy were independent predictors of an IDH1 wild-type in the least absolute shrinkage and selection operator. The area under the receiver operating curve for the prediction model was 0.853. The skewness and cluster shade of ADC, energy, and correlation of fractional anisotropy were independent predictors of a 1p/19q codeletion in IDH1-mutant tumors in the least absolute shrinkage and selection operator. The area under the receiver operating curve was 0.807.

CONCLUSIONS:

Whole-tumor histogram and texture features of the ADC and fractional anisotropy maps are useful for predicting the IDH1-mutation and 1p/19q-codeletion status in World Health Organization grade II gliomas.

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Targeting the Clot in Acute Stroke [LETTERS]

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Intensity modulated radiotherapy in locally advanced thyroid cancer: Outcomes of a sequential phase I dose-escalation study

Publication date: Available online 7 March 2018
Source:Radiotherapy and Oncology
Author(s): K.P. Rooney, A.B. Miah, S.A. Bhide, M.T. Guerrero-Urbano, M.T. Sharabiani, K.L. Newbold, L. Grove, K.J. Harrington, C.M. Nutting
Background and purposeTo determine the safety and tolerability of dose-escalation using modestly accelerated IMRT in high-risk locally advanced thyroid cancer requiring post-operative radiotherapy, and to report preliminary data on efficacy.Materials and methodsA sequential Phase I dose-escalation design was used. Dose level one (DL1) received 58.8 Gy/28F to the post-operative bed and 50 Gy/28F to elective nodes. DL2 received 66.6 Gy/30F to the thyroid bed, 60 Gy/30F to post-operative nodal levels and 54 Gy/30F to elective nodal levels. Acute (NCICTCv.2.0) and late toxicities (RTOG and modified LENTSOM) were recorded. The primary endpoint was the number of patients with ≥Grade 3 (G3) toxicity at 12 months post-treatment.ResultsFifteen patients were recruited to DL1 and twenty-nine to DL2. At 12 months ≥G3 toxicities were 8.3% in both DL1 and DL2. At 60 months, ≥G3 toxicity was reported in 3 (33%) patients in DL1 and 1 (7%) in DL2. One patient in DL2 died at 24 months from radiation-induced toxicity. Time to relapse and overall survival rates were higher in DL2, but this was not statistically significant.Dose-escalation using this accelerated regimen can be safely performed with a toxicity profile similar to reported series using conventional doses.



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Fast and robust adaptation of organs-at-risk delineations from planning scans to match daily anatomy in pre-treatment scans for online-adaptive radiotherapy of abdominal tumors

Publication date: Available online 8 March 2018
Source:Radiotherapy and Oncology
Author(s): Vikas Gupta, Yibing Wang, Alejandra Méndez Romero, Andriy Myronenko, Petr Jordan, Calvin Maurer, Ben Heijmen, Mischa Hoogeman
PurposeTo validate a novel deformable image registration (DIR) method for online adaptation of planning organ-at-risk (OAR) delineations to match daily anatomy during hypo-fractionated RT of abdominal tumors.Materials and methodsFor 20 liver cancer patients, planning OAR delineations were adapted to daily anatomy using the DIR on corresponding repeat CTs. The DIR's accuracy was evaluated for the entire cohort by comparing adapted and expert-drawn OAR delineations using geometric (Dice Similarity Coefficient (DSC), Modified Hausdorff Distance (MHD) and Mean Surface Error (MSE)) and dosimetric (Dmax and Dmean) measures.ResultsFor all OARs, DIR achieved average DSC, MHD and MSE of 86%, 2.1 mm, and 1.7 mm, respectively, within 20 s for each repeat CT. Compared to the baseline (translations), the average improvements ranged from 2% (in heart) to 24% (in spinal cord) in DSC, and 25% (in heart) to 44% (in right kidney) in MHD and MSE. Furthermore, differences in dose statistics (Dmax, Dmean and D2%) using delineations from an expert and the proposed DIR were found to be statistically insignificant (p > 0.01).ConclusionThe validated DIR showed potential for online-adaptive radiotherapy of abdominal tumors as it achieved considerably high geometric and dosimetric correspondences with the expert-drawn OAR delineations, albeit in a fraction of time required by experts.



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Contents

Publication date: February 2018
Source:Radiotherapy and Oncology, Volume 126, Issue 2





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Editorial Board

Publication date: February 2018
Source:Radiotherapy and Oncology, Volume 126, Issue 2





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Improving the quality of radiation oncology: 10years’ experience of QUATRO audits in the IAEA Europe Region

Publication date: February 2018
Source:Radiotherapy and Oncology, Volume 126, Issue 2
Author(s): Joanna Izewska, Mary Coffey, Pierre Scalliet, Eduardo Zubizarreta, Tania Santos, Ioannis Vouldis, Peter Dunscombe
Background and purposeThe IAEA has developed a methodology for comprehensive quality audits of radiotherapy practices called Quality Assurance Team for Radiation Oncology (QUATRO). This study explores the factors that impacted quality of care among QUATRO audited centres in the IAEA Europe Region.Materials and methodsThe 31 QUATRO reports collected over 10years include extensive data describing the quality of radiotherapy at the audited centres. A coding key was developed to aggregate and review these data in terms of recommendations for improvement and positive findings (commendations).ResultsOverall 759 recommendations and 600 commendations were given. Eight centres recognized as centres of competence differed from other centres mostly because they operated complete quality management systems and were adequately staffed. Other centres had excessive staff workloads and many gaps in the process of care. Insufficient equipment levels were prevalent. Patient centredness, communication, dosimetry, quality control and radiation protection were frequently commended by QUATRO.ConclusionsThis analysis points to barriers to quality care such as insufficient staffing, education/training, equipment and lack of quality management. It highlights the correlation between the human resources availability and quality of care. It has also identified common action items for enhancing quality of radiotherapy programmes in the Region.



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Remembering Professor Stanley Dische (1927–2017)

Prof Stanley Dische, one of the great pioneers of modern radiotherapy, sadly died on 2nd November 2017 at the age of 90 years. Stanley Dische was born in London on 27th March 1927 and qualified in medicine from the Middlesex Hospital Medical School, London, in 1950. He worked initially as an Assistant Pathologist in the Bland Sutton Institute of Pathology at the Middlesex Hospital and subsequently as Pathologist to the Royal Air Force Institute of Pathology and Tropical Medicine. During this time he completed his research for his MD thesis entitled 'The investigation of symptomless glycosuria'.

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Editorial Board

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Contents

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Application of 19F quantitative NMR to pharmaceutical analysis

Abstract

The presence of fluorine in an active pharmaceutical ingredient (API) can impart important pharmacological attributes with regards to metabolism, stability, and selectivity. As such, nearly one-third of newly approved small molecule drugs contain at least one fluorine atom. ¹⁹F is 100% naturally abundant lending to virtually unimpeded detection of fluorine-containing molecules, even in complex mixtures. Despite these promising characteristics, the thorough evaluation of a method for ¹⁹F qNMR (quantitative NMR) has been lacking. Herein we present experimental methodology and optimized parameters for uniform quantitative sampling of fluorine-containing drugs and we compare results obtained using both gravimetric and absolute concentration methods for data reduction.

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Fast and robust adaptation of organs-at-risk delineations from planning scans to match daily anatomy in pre-treatment scans for online-adaptive radiotherapy of abdominal tumors

To validate a novel deformable image registration (DIR) method for online adaptation of planning organ-at-risk (OAR) delineations to match daily anatomy during hypo-fractionated RT of abdominal tumors.

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Quantitative evaluation of facial hypoplasia and airway obstruction in infants with syndromic craniosynostosis: relationship with skull base and splanchnocranium sutural pattern

Abstract

Purpose

Craniosynostostic syndromes are due to multisuture synostoses and affect the entire craniofacial skeleton. This study analyzed the facial complex and airways to quantify the relationship between insufficient facial growth, airways obstruction, and the sutural pattern of the splanchnocranium and cranial fossae.

Methods

Preoperative high-resolution CT images in 19 infants with syndromic craniosynostosis were quantitatively analyzed. Because all children showed involvement of minor sutures/synchondroses coursing in the posterior cranial fossa, they were divided into three groups according to the synostotic involvement of "minor" sutures/synchondroses coursing in anterior (ACF) and middle (MCF) cranial fossae: group 1 (ACF), group 2 (MCF), and group 3 (ACF-MCF). Analysis of the facial complex and airway was performed. Each group was compared with age-matched healthy subjects.

Results

Premature closure of skull base synchondroses of ACF and MCF was found only in groups MCF and ACF-MCF. Group MCF showed synostosis in the posterior branch of the coronal ring and reduced anterior hemifossae lengths while group ACF-MCF showed synostosis in the anterior branch of the coronal ring and reduced middle hemifossae lengths. No group showed reduced maxillary or mandibular volumes but group MCF showed synostosis of the zygomaticomaxillary sutures and maxillary retrusion. All groups showed reduced airway volume but group 2 had a higher degree of airway hypoplasia.

Conclusion

The skull base synostotic process drives the changes in facial complex growth and airway obstruction. Premature closure of synchondroses/sutures in the posterior branch of the coronal ring causes insufficient facial growth, maxillary retrusion, and more severe airway reduction.

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Postoperative in-stent protrusion is an important predictor of perioperative ischemic complications after carotid artery stenting

Publication date: Available online 7 March 2018
Source:Journal of Neuroradiology
Author(s): Mikiya Beppu, Yohei Mineharu, Hirotoshi Imamura, Hidemitsu Adachi, Chiaki Sakai, Shoichi Tani, Koichi Arimura, So Tokunaga, Nobuyuki Sakai
Background And PurposeAlthough in-stent protrusion is a potential risk factor of thromboembolism following carotid artery stenting, the correlation between in-stent protrusion and postoperative ipsilateral stroke has not been well examined.Materials And MethodsWe retrospectively reviewed 342 consecutive carotid artery lesions in 319 patients who underwent carotid artery stenting between April 2008 and April 2015. After excluding cases with carotid artery dissection and acute occlusion, 301 lesions in total of 277 patients were included in the analysis. We examined the association between in-stent protrusion, which was detected by intravascular ultrasound, and postoperative ipsilateral stroke within 30 days.ResultsIn-stent protrusion was observed in 47 (15.6%) lesions, of which postoperative ipsilateral stroke within 30 days occurred with 4 (8.5%) lesions. All these events occurred within 10 days after treatment. On the other hand, only 1 (0.39%) of the 256 lesions without in-stent protrusion showed this symptom, and the event occurred at 30 days after treatment. Thus, lesions with in-stent protrusion had higher cumulative risk of ipsilateral stroke than those without in-stent protrusion (8.5% vs 0.4% at 30days, log-rank p < 0.001). In-stent protrusion, which was more often seen in symptomatic lesions, was associated with a vulnerable plaque assessed by MRI. After adjustment for postoperative stroke risks such as symptomatic lesions, plaque vulnerability, age or sex, in-stent protrusion was still significantly associated with postoperative ipsilateral stroke within 30 days (OR = 27.03, p = 0.001).ConclusionsPostoperative ipsilateral stroke was observed more frequently in patients with demonstrated ISP following CAS.



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CT angiography for one-year follow-up of intracranial aneurysms treated with the WEB device: Utility in evaluating aneurysm occlusion and WEB compression at one year

Publication date: Available online 7 March 2018
Source:Journal of Neuroradiology
Author(s): Hélène Raoult, François Eugène, Anthony Le Bras, Géraldine Mineur, Béatrice Carsin-Nicol, Jean-Christophe Ferré, Jean-Yves Gauvrit
Background and purposeThe WEB is an innovative flow disruption device for cerebral aneurysm embolization with rapidly expanding indications. Our purpose was to evaluate the diagnostic performance of CTA at 1-year follow-up of aneurysms treated with the WEB.Materials and methodsBetween April 2014 and May 2016, the study prospectively included patients treated with the WEB at our institution, and followed up within 24hours by CTA and at 1 year by CTA, TOF MRA and DSA. The diagnostic quality of imaging data was assessed based on the confidence index, artifacts, and WEB shape depiction. The imaging diagnostic performance was assessed using 3 criteria at 1 year: aneurysm occlusion status and worsening, and WEB shape compression. Interobserver and intermodality agreement was determined by calculating κ values.ResultsThe study ultimately included 16 patients (9 women, mean age 53 ± 7.6 years). CTA quality confidence was scored as 2/2, artifacts 0.4/2 and WEB shape depiction 1.9/2, superior to TOF MRA for the latter two criteria. Aneurysm occlusion was adequate in 93.7% of patients, with CTA showing excellent interobserver reproducibility and agreement with DSA on a 4-grade scale (κ = 1.00), while TOF MRA yielded good reproducibility (κ = 0.76) and agreement with DSA (κ = 0.69). CTA also identify aneurysm occlusion worsening (43.7%) and WEB compression (81.2%) in excellent agreement with DSA (κ = 0.85 and 1.00).ConclusionsCTA is a reproducible and reliable technique for the follow-up of aneurysms treated with the WEB device.



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Objective evaluation of cerebrovascular reactivity for acetazolamide predicts cerebral hyperperfusion after carotid artery stenting: Comparison with region of interest methods

Publication date: Available online 7 March 2018
Source:Journal of Neuroradiology
Author(s): Kouichi Misaki, Naoyuki Uchiyama, Anri Inaki, Seigo Kinuya, Iku Nambu, Tomoya Kamide, Masanao Mohri, Yasuhiko Hayashi, Mitsutoshi Nakada
Background And PurposeHemodynamic impairments are considered risk factors of cerebral hyperperfusion after carotid artery stenting (CAS); measurement by SPECT using a subjective ROI method lacks consistency and reproducibility.Materials And MethodsThe present study compared objective perfusion analysis (stereotactic extraction estimation [SEE] method) with the ROI method for preoperative SPECT to predict the hyperperfusion phenomenon (HPP) after CAS. Preoperative resting asymmetry index (CBF ratio from the affected to unaffected hemisphere) and cerebrovascular reactivity (CVR) to acetazolamide were measured by N-isopropyl-p-[¹²³I]-iodoamphetamine SPECT using the SEE and ROI method in 84 patients. CBF was also measured the day after CAS. Perfusion data with the highest area under the curve (AUC) by receiver-operating characteristic (ROC) analysis was considered a perfusion risk factor of HPP. Multivariate analyses for clinical characteristics and perfusion risk factors were performed to determine predictors of HPP.Resultsthe HPP was observed in 10 patients (11.9%). Female sex, contralateral stenosis, and degree of stenosis were significantly associated with HPP development on univariate analysis, and symptomatic stenosis was not found to be a significant factor. On SPECT analysis, CVR in the MCA area by SEE method had the highest AUC (0.981). Multivariate analysis showed that CVR in the MCA area was a significant predictor of HPP (p=0.041). To predict hyperperfusion, the ROC curve of the CVR showed a cutoff value of -0.60%, sensitivity of 94.6%, and specificity of 100% (p<0.001).Conclusionsobjective SEE method had better a predictive capability than ROI method to identify risk of hyperperfusion after CAS.



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Surgery first/early orthognathic approach may yield poorer postsurgical stability than conventional orthodontics first approach: a systematic review and meta-analysis

Publication date: Available online 7 March 2018
Source:Oral Surgery, Oral Medicine, Oral Pathology and Oral Radiology
Author(s): Hongpu Wei, Zhixu Liu, Jiajie Zang, Xudong Wang
ObjectiveThere are conflicting views on the postsurgical stability of surgery first and surgery early approach in orthognathic surgery. We systematically reviewed the literature to compare the difference of postsurgical stability between surgery first/early approach(SFEA) and conventional ortho-first approach(COA).Study DesignPubMed, Embase, and Cochrane Library were searched for studies related to the postsurgical stability of SFEA. The primary outcome was the horizontal relapse at the pogonion. Weighted Mean Difference(WMD) with 95% CIs were pooled using a random-effects model.ResultsWe analyzed 12 studies (total of 498 participants). The pooled estimate suggested that the SFEA group manifest less postsurgical stability than COA group (WMD,1.50; P<0.00001), with moderate heterogeneity (I² = 53%). The result of subgroup analysis yielded no subgroup difference. Sensitivity analysis by omitting one study at a time further validated the robustness of the result.ConclusionsBased on the meta-analysis, the mandible tends to rotate counterclockwise more in the SFEA group, which indicate a poorer postsurgical stability than COA group. Patient screening and treatment plan should be reviewed carefully to compensate for possible postoperative relapse when adopting SFEA.



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Computer-assisted resection and reconstruction of bilateral osteoradionecrosis of the mandible using two separate flaps prepared from a single fibula

Publication date: Available online 7 March 2018
Source:Oral Surgery, Oral Medicine, Oral Pathology and Oral Radiology
Author(s): Rui Chen, Han-qing Zhang, Zi-xian Huang, Shi-hao Li, Da-ming Zhang, Zhi-quan Huang
Objectives: Osteoradionecrosis of the mandible is a late radiation-induced complication that becomes a major concern of head and neck cancer survivors. Study Design: In this study, we present a case of a nasopharyngeal carcinoma (NPC) patient who developed extensive bilateral osteoradionecrosis of the ascending ramus of the mandible. Preoperative virtual surgical planning was performed, the obtained data was then utilized to fabricate patient-specific cutting templates. The bilateral mandibular defects were reconstructed using two separate flaps prepared from a single fibula. Results: Both of the defects were successfully reconstructed, and aesthetic and functional results were achieved. Conclusion: Bilateral mandibular osteoradionecrosis can be managed with virtual surgical planning and reconstructed using two separate flaps prepared from a single fibula.



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Warthin's Tumour :RadioPath Integrated Discussion

Warthin tumours, also known as lymphomatous papillary cystadenomas, are benign, sharply demarcated tumours of the salivary gland. They are of lymphoid origin and most commonly arise from parotid gland tail. 

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Investigation of fMRI Analysis Method to Visualize the Difference in the Brain Activation Timing

Publication date: Available online 7 March 2018
Source:Academic Radiology
Author(s): Sumito Maruyama, Kenzo Muroi, Yoshiyuki Hosokai
Rationale and ObjectivesIn general functional magnetic resonance imaging (fMRI) analysis, the task onset time of the statistical model is typically set according to the timing of stimulation. In this study, using a high temporal resolution fMRI data, we examined the way of dynamically visualizing the difference in the activation timing between the brain activation areas by analyzing the task onset time of the statistical model shifted from the actual stimulation timing.Materials and MethodsfMRI data with high temporal resolution was acquired using 3 T magnetic resonance imaging for 10 right-handed healthy volunteers. While being scanned, the volunteers completed a task that comprised two sets of a rest and right hand grip movement task. Statistical Parametric Mapping 12 (SPM12) software was used to analyze fMRI data. After preprocessing, statistical analyses were performed by shifting the task onset time on the statistical model by about 1 second forward or backward from the actual stimulation timing. Activation maps of multiple time phases were then created.ResultsActivity was observed to the left of the primary motor area and the supplementary motor area and to the right of the cerebellum (familywise error rate, P < .05). In the right hand grip movement, the primary motor area and the supplementary motor area were activated from 1.12 to 4.48 seconds earlier than the cerebellum.ConclusionsUsing this analysis method, we visualized the differences in activation timings of different areas of the brain.



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Magnetic Resonance Imaging Parameters in Predicting the Treatment Outcome of High-intensity Focused Ultrasound Ablation of Uterine Fibroids With an Immediate Nonperfused Volume Ratio of at Least 90%

Publication date: Available online 7 March 2018
Source:Academic Radiology
Author(s): Bilgin Keserci, Nguyen Minh Duc
Rationale and ObjectivesWe aimed to investigate the role of magnetic resonance imaging parameters in predicting the treatment outcome of high-intensity focused ultrasound (HIFU) ablation of uterine fibroids with a nonperfused volume (NPV) ratio of at least 90%.Material and MethodsA total of 120 women who underwent HIFU treatment were divided into groups 1 (n = 72) and 2 (n = 48), comprising patients with an NPV ratio of at least 90% and less than 90%, respectively. Multivariate logistic regression analyses were carried out to investigate the potential predictors of the NPV ratio of at least 90%. The NPV ratios immediately post-treatment, therapeutic efficacy at 6 months' follow-up, and safety in terms of adverse effects and changes in anti-Mullerian hormone level were assessed.ResultsBy introducing multiple predictors obtained from multivariate analyses into a generalized estimating equation model, the results showed that the thickness of the subcutaneous fat layer in the anterior abdominal wall, peak enhancement of fibroid, time to peak of fibroid, and the ratio of area under the curve of fibroid to myometrium were statistically significant, except T2 signal intensity ratio of fibroid to myometrium, hence predicting an NPV ratio of at least 90%. No serious adverse effects and no significant difference between the anti-Mullerian hormone levels before or 6 months post-treatment were reported.ConclusionsThe findings in this study suggest that the achievement of NPV ratio of at least 90% in magnetic resonance imaging-guided HIFU treatment of uterine fibroids based on prediction model appears clinically possible without compromising the safety of patients.



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Techniques of cadaver perfusion for surgical training: a systematic review.

Techniques of cadaver perfusion for surgical training: a systematic review.

Surg Radiol Anat. 2018 Mar 06;:

Authors: Bellier A, Chanet A, Belingheri P, Chaffanjon P

Abstract
PURPOSE: The objective of this study was to identify the most appropriate cadaver perfusion techniques for surgical training through a systematic review with a description of the protocols used.
METHODS: The search strategy included PubMed and reference tracking. Studies were identified by searching the electronic Medline databases. The search concepts included perfusion, cadavers and simulation training, and the protocol used is reported. This resulted in a qualitative review of 12 articles out of 250 articles consulted. We collected all the important data from these 12 articles.
RESULTS: Regarding the characteristics of the studies and the declotting or perfusion techniques, the results were heterogeneous. Indeed, in several studies, a good deal of information was unclear or insufficiently precise, making it unfeasible to summarize the data. The methods used were not sufficiently explicit and detailed. However, a majority of the fresh cadavers used tap water for declotting. Perfusion, type of fluid, number of pumps, pressure, pulsatility, and arterial or venous approaches differed greatly. Only two studies fulfilled five of our six realism criteria for surgical simulation.
CONCLUSIONS: This systematic review provided an overview of all the different cadaver perfusion techniques. It could be used to establish a reference method of a simulation model.

PMID: 29511810 [PubMed - as supplied by publisher]

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Reducing the Number of Measurements in Liver Point Shear-Wave Elastography: Factors that Influence the Number and Reliability of Measurements in Assessment of Liver Fibrosis in Clinical Practice.

Reducing the Number of Measurements in Liver Point Shear-Wave Elastography: Factors that Influence the Number and Reliability of Measurements in Assessment of Liver Fibrosis in Clinical Practice.

Radiology. 2018 Mar 06;:172104

Authors: Fang C, Jaffer OS, Yusuf GT, Konstantatou E, Quinlan DJ, Agarwal K, Quaglia A, Sidhu PS

Abstract
Purpose To identify the minimum number of measurements required for the noninvasive assessment of liver fibrosis by using point shear-wave elastography (pSWE) and determine whether the use of a reliability indicator such as interquartile range [IQR]-to-median ratio will affect diagnostic performance. Materials and Methods Ten liver shear-wave velocity (SWV) measurements by pSWE were obtained in 232 participants. Interclass correlation coefficients (ICC) between the median of the first two through the first nine measurements and all 10 measurements were calculated; the minimum number of measurements with ICC greater than 0.95 versus all 10 measurements was determined. The diagnostic performance of the minimum number of measurements and 10 measurements in identifying significant (Ishak stage, ≥3) and severe fibrosis or cirrhosis (Ishak stage, ≥5) was compared by using areas under the receiver operating characteristic curve. These were compared between measurements that demonstrated higher or lower reliability (IQR-to-median ratio of ≤ 30% and IQR-to-median ratio of > 30%, respectively). Results Compared with 10 measurements, a minimum of six SWV measurements was required. The overall area under the curve for diagnosing significant (areas under the receiver operating characteristic curve, 0.828 vs 0.839; P = .487) and severe fibrosis or cirrhosis (0.953 vs 0.969, respectively; P = .145) did not differ according to number of measurements (six vs 10); a median of six measurements resulted in only limited disagreement (nine of 232 [3.9%]) versus histologic evaluation. When using 10 measurements, higher reliability measurements showed a lower percentage of discordance between pSWE and significant fibrosis and severe fibrosis or cirrhosis (22 [14.7%] and three [2.0%] of 150 cases, respectively) compared with lower reliability measurements (26 [31.7%] and eight [9.8%] of 82 cases, respectively). Significant fibrosis was an independent predictor for lower reliability (hazard ratio, 2.22; P < .020). Conclusion A limited number of SWV measurements (median six vs median 10) were required for the assessment of liver fibrosis by using pSWE. The number of measurements had less influence on the diagnostic accuracy compared with lower reliability measurements. © RSNA, 2018 Online supplemental material is available for this article.

PMID: 29514018 [PubMed - as supplied by publisher]

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MR Imaging of Rectal Cancer: Radiomics Analysis to Assess Treatment Response after Neoadjuvant Therapy.

MR Imaging of Rectal Cancer: Radiomics Analysis to Assess Treatment Response after Neoadjuvant Therapy.

Radiology. 2018 Mar 07;:172300

Authors: Horvat N, Veeraraghavan H, Khan M, Blazic I, Zheng J, Capanu M, Sala E, Garcia-Aguilar J, Gollub MJ, Petkovska I

Abstract
Purpose To investigate the value of T2-weighted-based radiomics compared with qualitative assessment at T2-weighted imaging and diffusion-weighted (DW) imaging for diagnosis of clinical complete response in patients with rectal cancer after neoadjuvant chemotherapy-radiation therapy (CRT). Materials and Methods This retrospective study included 114 patients with rectal cancer who underwent magnetic resonance (MR) imaging after CRT between March 2012 and February 2016. Median age among women (47 of 114, 41%) was 55.9 years (interquartile range, 45.4-66.7 years) and median age among men (67 of 114, 59%) was 55 years (interquartile range, 48-67 years). Surgical histopathologic analysis was the reference standard for pathologic complete response (pCR). For qualitative assessment, two radiologists reached a consensus. For radiomics, one radiologist segmented the volume of interest on high-spatial-resolution T2-weighted images. A random forest classifier was trained to separate the patients by their outcomes after balancing the number of patients in each response category by using the synthetic minority oversampling technique. Statistical analysis was performed by using the Wilcoxon rank-sum test, McNemar test, and Benjamini-Hochberg method. Results Twenty-one of 114 patients (18%) achieved pCR. The radiomic classifier demonstrated an area under the curve of 0.93 (95% confidence interval [CI]: 0.87, 0.96), sensitivity of 100% (95% CI: 0.84, 1), specificity of 91% (95% CI: 0.84, 0.96), positive predictive value of 72% (95% CI: 0.53, 0.87), and negative predictive value of 100% (95% CI: 0.96, 1). The diagnostic performance of radiomics was significantly higher than was qualitative assessment at T2-weighted imaging or DW imaging alone (P < .02). The specificity and positive predictive values were significantly higher in radiomics than were at combined T2-weighted and DW imaging (P < .0001). Conclusion T2-weighted-based radiomics showed better classification performance compared with qualitative assessment at T2-weighted and DW imaging for diagnosing pCR in patients with locally advanced rectal cancer after CRT. © RSNA, 2018 Online supplemental material is available for this article.

PMID: 29514017 [PubMed - as supplied by publisher]

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Functional Connectivity of the Corticobasal Ganglia-Thalamocortical Network in Parkinson Disease: A Systematic Review and Meta-Analysis with Cross-Validation.

Functional Connectivity of the Corticobasal Ganglia-Thalamocortical Network in Parkinson Disease: A Systematic Review and Meta-Analysis with Cross-Validation.

Radiology. 2018 Mar 07;:172183

Authors: Ji GJ, Hu P, Liu TT, Li Y, Chen X, Zhu C, Tian Y, Chen X, Wang K

Abstract
Purpose To quantitatively summarize the functional connectivity (FC) feature of the corticobasal ganglia-thalamocortical (CBTC) network in patients with Parkinson disease (PD) by means of a meta-analysis with cross-validation. Materials and Methods For this prospective study, a systematic literature search in the PubMed and EMBASE databases was performed for resting-state functional magnetic resonance (MR) imaging studies of PD published between January 2000 and May 2017. Then, a coordinate-based meta-analysis was conducted by Effect Size-Signed Differential Mapping. A cross-validation analysis was performed by using an independent resting-state functional MR imaging data set that contained 25 patients with PD and 19 age-, sex-, and education-matched healthy control participants. Two-sample t test was performed on FC maps between PD and control groups. Results Thirty studies with 854 patients with PD and 831 control participants were included in this meta-analysis. The main meta-analysis found increased FC in the left pre- and postcentral gyrus in patients with PD compared with healthy control participants (z = 2.6; P < .001). The abnormality of the postcentral gyrus was further confirmed by subgroup meta-analyses on medication-naive (n = 25; z = 2.2; P < .001) and medication-off (n = 11; z = 1.5; P < .001) experiments, which suggested that the finding was unaffected by medication. The abnormality of the postcentral gyrus was cross-validated by the independent data set (t = 5.0; P < .05), which suggested a high reproducibility and generalizability. Conclusion This meta-analysis emphasizes the left postcentral gyrus as a critical region in PD, which may become a potential target for clinical intervention. © RSNA, 2018 Online supplemental material is available for this article.

PMID: 29514016 [PubMed - as supplied by publisher]

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The ERICA Score: An MR Imaging-based Visual Scoring System for the Assessment of Entorhinal Cortex Atrophy in Alzheimer Disease.

The ERICA Score: An MR Imaging-based Visual Scoring System for the Assessment of Entorhinal Cortex Atrophy in Alzheimer Disease.

Radiology. 2018 Mar 07;:171888

Authors: Enkirch SJ, Traschütz A, Müller A, Widmann CN, Gielen GH, Heneka MT, Jurcoane A, Schild HH, Hattingen E

Abstract
Purpose To establish and evaluate a visual score focused on entorhinal cortex atrophy (ERICA), as the entorhinal cortex is one of the first brain structures affected in Alzheimer disease (AD). Materials and Methods In this retrospective study, ERICA was visually evaluated with magnetic resonance imaging (2009-2016). First, a four-point ERICA score was developed by using data in 48 consecutive subjects (20 patients with AD and 28 control subjects). Then, in the main analysis, ERICA and the standard medial temporal lobe atrophy (MTA) scores were determined in an independent cohort of 60 patients suspected of having AD (mean age, 69.4 years; range, 46-86 years) and in 60 age-matched patients with subjective cognitive decline (SCD) (mean age, 72.4 years; range 50-87 years). Score performances were evaluated with κ statistics, receiver operating characteristic analysis, t tests, and analysis of variance according to the Standards for Reporting of Diagnostic Accuracy Studies. Results Patients with AD had higher MTA scores (mean, 2.13) and ERICA scores (mean, 2.05) than patients with SCD (P < .001). An ERICA score of 2 or greater achieved a higher diagnostic accuracy (91%) than the MTA score (74%), with a sensitivity of 83% versus 57% and a specificity of 98% versus 92% in discriminating dementia caused by AD from SCD (P < .001). The ERICA score was correlated with amyloid β 42/40 ratio (ρ = -0.54, P < .001) and with cerebrospinal fluid tau (ρ = 0.35, P = .001) and p-tau (ρ = 0.31, P = .004). In multivariable linear regression analysis, ERICA was associated with verbal learning and recall (β = -.40 and -.41), nonverbal recall (β = -.28), and cued recall (β = -.41, P ≤ .002 for all). Conclusion An ERICA score of 2 or greater indicates probable AD with high diagnostic accuracy. © RSNA, 2018 Online supplemental material is available for this article.

PMID: 29514015 [PubMed - as supplied by publisher]

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Adaptive immune cells are necessary for the enhanced therapeutic effect of sorafenib-loaded nanoparticles.

Adaptive immune cells are necessary for the enhanced therapeutic effect of sorafenib-loaded nanoparticles.

Biomater Sci. 2018 Mar 07;:

Authors: Zhao ZB, Long J, Zhao YY, Yang JB, Jiang W, Liu QZ, Yan K, Li L, Wang YC, Lian ZX

Abstract
Sorafenib is a kinase inhibitor approved for the treatment of primary kidney cancer, advanced primary liver cancer, and radioactive iodine resistant advanced thyroid carcinoma. However, sorafenib usually causes serious side effects, which limit its antitumor effect. Nanoparticle based drug delivery systems have been widely used to enhance the therapeutic effects and reduce the side effects of this drug by the enhanced permeability and retention (EPR) effect. Herein, to improve the therapeutic effect of sorafenib, we developed poly(ethylene glycol)-b-poly(lactic acid-co-glycolic acid) (PEG-PLGA) based nanoparticles by a dialysis method for sorafenib encapsulation. After intravenous injection of the sorafenib loaded nanoparticles (NPsorafenib), the tumor growth of mice bearing B16-F10, MC38 and LLC tumor was significantly inhibited. Meanwhile, the dose of sorafenib was reduced to one ninth and the side effects on the hematopoietic system and immune system were abrogated. More importantly, the tumor growth inhibition effect of NPsorafenib was dramatically reduced in B16-F10 bearing Rag1-/- mice which are adaptive immune cell defective, indicating that the antitumor effects of NPsorafenib are dependent on the adaptive immune cells. These results emphasize the indispensable role of the adaptive immune system in nano-drug mediated antitumor effects and the adaptive immune system should be considered as an important factor for clinical applications.

PMID: 29512660 [PubMed - as supplied by publisher]

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Major Reduction in Axillary Lymph Node Dissections After Neoadjuvant Systemic Therapy for Node-Positive Breast Cancer by combining PET/CT and the MARI Procedure.

Major Reduction in Axillary Lymph Node Dissections After Neoadjuvant Systemic Therapy for Node-Positive Breast Cancer by combining PET/CT and the MARI Procedure.

Ann Surg Oncol. 2018 Mar 06;:

Authors: van der Noordaa MEM, van Duijnhoven FH, Straver ME, Groen EJ, Stokkel M, Loo CE, Elkhuizen PHM, Russell NS, Vrancken Peeters MTFD

Abstract
BACKGROUND: Axillary lymph node dissection (ALND) is frequently performed for node-positive (cN+) breast cancer patients. Combining positron emission tomography/computed tomography (PET/CT) before-NST and the MARI (marking axillary lymph nodes with radioactive iodine seeds) procedure after neoadjuvant systemic therapy (NST) has the potential for avoiding unnecessary ALNDs. This report presents the results from implementation of this strategy.
METHODS: All breast cancer patients treated with NST at the Netherlands Cancer Institute who underwent a PET/CT and the MARI procedure from July 2014 to July 2017 were included in the study. All the patients underwent tailored axillary treatment according to a protocol based on the combined results of PET/CT before NST and the MARI procedure after NST. With this protocol, patients showing one to three FDG-avid axillary lymph nodes (ALNs) on PET/CT (cN<4) and a tumor-negative MARI node receive no further axillary treatment. All cN (<4) patients with a tumor-positive MARI node receive locoregional radiotherapy, as well as patients with four or more FDG-avid ALNs [cN(4+)] and a tumor-negative MARI node after NST. An ALND is performed only for cN(4+) patients with a tumor-positive MARI node.
RESULTS: The data of 159 patients who received a PET/CT before NST and a MARI procedure after NST were analyzed. Of these patients, 110 had one to three FDG-avid ALNs and 49 patients showed four or more FDG-avid ALNs on PET/CT before NST. For 130 patients (82%), ALND was omitted. Locoregional radiotherapy was administered to 91 patients (57%), and 39 patients (25%) received no further axillary treatment.
CONCLUSION: Combining pre-NST axillary staging with PET/CT and post-NST staging with the MARI procedure resulted in an 82% reduction of ALNDs for cN + breast cancer patients.

PMID: 29511992 [PubMed - as supplied by publisher]

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False-positive radioiodine accumulation in a huge pelvic mass after thyroidectomy for papillary carcinoma, a case report from Syria.

False-positive radioiodine accumulation in a huge pelvic mass after thyroidectomy for papillary carcinoma, a case report from Syria.

J Surg Case Rep. 2018 Feb;2018(2):rjy028

Authors: Almohamad FA, Ahmad T, Ahmad B, Hussain K, Hadid L, Zein M, Ahmad M

Abstract
Iodine has always been connected to thyroid gland, and the fact that thyroid tissue traps, organificates and stores iodine more than other tissues is well known, hence the use of radioiodine as a diagnostic and therapeutic tool for thyroid disorders. However, false-positive cases do occur. We present a case of a 34-year-old patient who underwent total thyroidectomy for papillary carcinoma. Results of follow up TSH, thyroglobulin and thyroglobulin antibody tests after surgery lead to two rounds of radioactive iodine. After that, a radioiodine whole-body scan showed high uptake in the pelvis above bladder. Computed tomography scan showed a pelvic heterogeneous mass with some calcifications. Surgical removal and subsequent pathology confirmed the absence of metastasis. The final pathological diagnosis was serous cystadenoma, endometriosis cyst and leiomyoma. As the real cause behind false-positive iodine uptake by these tissues has yet to be determined, careful assessment should be considered in any suspicious case.

PMID: 29511526 [PubMed]

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Hemodynamic vascular biomarkers for initiation of paraclinoid internal carotid artery aneurysms using patient-specific computational fluid dynamic simulation based on magnetic resonance imaging

Abstract

Purpose

We performed computational fluid dynamics (CFD) for patients with and without paraclinoid internal carotid artery (ICA) aneurysms to evaluate the distribution of vascular biomarkers at the aneurysm initiation sites of the paraclinoid ICA.

Methods

This study included 35 patients who were followed up for aneurysms using 3D time of flight (TOF) magnetic resonance angiography (MRA) and 3D cine phase-contrast MR imaging. Fifteen affected ICAs were included in group A with the 15 unaffected contralateral ICAs in group B. Thirty-three out of 40 paraclinoid ICAs free of aneurysms and arteriosclerotic lesions were included in group C. We deleted the aneurysms in group A based on the 3D TOF MRA dataset. We performed CFD based on MR data set and obtained wall shear stress (WSS), its derivatives, and streamlines. We qualitatively evaluated their distributions at and near the intracranial aneurysm initiation site among three groups. We also calculated and compared the normalized highest (nh-) WSS and nh-spatial WSS gradient (SWSSG) around the paraclinoid ICA among three groups.

Results

High WSS and SWSSG distribution were observed at and near the aneurysm initiation site in group A. High WSS and SWSSG were also observed at similar locations in group B and group C. However, nh-WSS and nh-SWSSG were significantly higher in group A than in group C, and nh-SWSSG was significantly higher in group A than in group B.

Conclusion

Our findings indicated that nh-WSS and nh-SWSSG were good biomarkers for aneurysm initiation in the paraclinoid ICA.

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Structural connectome with high angular resolution diffusion imaging MRI: assessing the impact of diffusion weighting and sampling on graph-theoretic measures

Abstract

Purpose

Advances in computational network analysis have enabled the characterization of topological properties of human brain networks (connectomics) from high angular resolution diffusion imaging (HARDI) MRI structural measurements. In this study, the effect of changing the diffusion weighting (b value) and sampling (number of gradient directions) was investigated in ten healthy volunteers, with specific focus on graph theoretical network metrics used to characterize the human connectome.

Methods

Probabilistic tractography based on the Q-ball reconstruction of HARDI MRI measurements was performed and structural connections between all pairs of regions from the automated anatomical labeling (AAL) atlas were estimated, to compare two HARDI schemes: low b value (b = 1000) and low direction number (n = 32) (LBLD); high b value (b = 3000) and high number (n = 54) of directions (HBHD).

Results

LBLD and HBHD data sets produced connectome images with highly overlapping hub structure. Overall, the HBHD scheme yielded significantly higher connection probabilities between cortical and subcortical sites and allowed detecting more connections. Small worldness and modularity were reduced in HBHD data. The clustering coefficient was significantly higher in HBHD data indicating a higher level of segregation in the resulting connectome for the HBHD scheme.

Conclusion

Our results demonstrate that the HARDI scheme as an impact on structural connectome measures which is not automatically implied by the tractography outcome. As the number of gradient directions and b values applied may introduce a bias in the assessment of network properties, the choice of a given HARDI protocol must be carefully considered when comparing results across connectomic studies.

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XXIst Symposium Neuroradiologicum

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