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! # Ola via Alexandros G.Sfakianakis on Inoreader

Πέμπτη, 26 Απριλίου 2018

Papillary thyroid microcarcinoma: characteristics at presentation, and evaluation of clinical and histological features associated with a worse prognosis in a Latin American cohort.

Papillary thyroid microcarcinoma: characteristics at presentation, and evaluation of clinical and histological features associated with a worse prognosis in a Latin American cohort.

Arch Endocrinol Metab. 2018 Feb;62(1):6-13

Authors: Domínguez JM, Nilo F, Martínez MT, Massardo JM, Muñoz S, Contreras T, Carmona R, Jerez J, González H, Droppelmann N, León A

Abstract
Objective We aimed to describe the presentation of papillary microcarcinoma (PTMC) and identify the clinical and histological features associated with persistence/recurrence in a Latin American cohort. Subjects and methods Retrospective study of PTMC patients who underwent total thyroidectomy, with or without radioactive iodine (RAI), and who were followed for at least 2 years. Risk of recurrence was estimated with ATA 2009 and 2015 classifications, and risk of mortality with 7th and 8th AJCC/TNM systems. Clinical data obtained during follow-up were used to detect structural and biochemical persistence/recurrence. Results We included 209 patients, predominantly female (90%), 44.5 ± 12.6 years old, 183 (88%) received RAI (90.4 ± 44.2 mCi), followed-up for a median of 4.4 years (range 2.0-7.8). The 7th and 8th AJCC/TNM system classified 89% and 95.2% of the patients as stage I, respectively. ATA 2009 and ATA 2015 classified 70.8% and 78.5% of the patients as low risk, respectively. Fifteen (7%) patients had persistence/recurrence during follow-up. In multivariate analysis, only lymph node metastasis was associated with persistence/recurrence (coefficient beta 4.0, p = 0.016; 95% CI 1.3-12.9). There were no PTMC related deaths. Conclusions Our series found no mortality and low rate of persistence/recurrence associated with PTMC. Lymph node metastasis was the only feature associated with recurrence in multivariate analysis. The updated ATA 2015 and 8th AJCC/TNM systems classified more PTMCs than previous classifications as low risk of recurrence and mortality, respectively.

PMID: 29694628 [PubMed - in process]



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Fast in situ gamma spectroscopy using hand-held spectrometer with NaI probe.

https:--linkinghub.elsevier.com-ihub-ima Related Articles

Fast in situ gamma spectroscopy using hand-held spectrometer with NaI probe.

J Environ Radioact. 2018 Aug;188:87-94

Authors: Guguła S, Kozak K, Mazur J, Grządziel D, Mroczek M

Abstract
In this work a hand-held spectrometer InSpector 1000 with NaI (Tl) 2″ x 2″ detector has been adapted to fast in situ gamma-ray spectroscopy. Two specially designed mounting stands with shielding have been built, allowing conducting measurements in different geometries. Three particular geometries (NW, IS50, IS00) have been chosen for efficiency calibration and further study. The first one (NW) is intended for small environmental samples (volume ca 140 cm3) collected on site. IS50 geometry is a typical in situ geometry meant for radioactivity measurements in soil with detector pointed towards the ground. In this geometry the probe is shielded and mounted 50 cm above the soil surface. The new proposed geometry IS00 is designed in the way that the detector is inserted directly into the soil in order to increase the counting efficiency. The methods of efficiency calibration involved using calibration standards (in NW geometry) and the results obtained in previous in situ measurements with InSpector 2000 portable spectrometer with HPGe detector and ISOCS™ Shield Systems, which is routinely used in environmental measurements. NW geometry turned out to be useful for natural radioisotopes concentrations (K-40, U-238 and Th-232), which significantly exceed typical values of those concentrations observed in Poland. Both IS50 and IS00 geometries are applicative for quick (2 h long measurement) evaluation of typical concentrations of K, U and Th in soils. The newly proposed geometry IS00 is superior as it showed lower detection limits and uncertainties as well as its handling was far easier than of IS50. Authors have proven that hand-held spectrometer InSpector 1000, together with mounting stands and shielding, can be successfully used for fast in situ gamma-spectroscopy. Its relatively small weight and good mobility are additional assets. Moreover, detailed procedures for measurements in each geometry have been developed to conduct such analyses properly.

PMID: 29021085 [PubMed - indexed for MEDLINE]



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11C-methionine positron emission tomography for target delineation of recurrent glioblastoma in re-irradiation planning

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Publication date: May–June 2018
Source:Reports of Practical Oncology & Radiotherapy, Volume 23, Issue 3
Author(s): Hidekazu Tanaka, Takahiro Yamaguchi, Kae Hachiya, Kazuhiro Miwa, Jun Shinoda, Masahide Hayashi, Shinichi Ogawa, Hironori Nishibori, Satoshi Goshima, Masayuki Matsuo
AimTo define the optimal margin on MRI scans in the re-radiation planning of recurrent glioblastoma using methionine positron emission tomography (MET-PET).BackgroundIt would be very useful if the optimal margin on MRI to cover the uptake area on MET-PET is known.Materials and MethodsCT, MRI, and MET-PET were performed separately over the course of 2 weeks. Among the MRI scans, we used the contrast-enhanced T1-weighted images (Gd-MRI) and T2-weighted images (T2-MRI). The Gd-MRI-based clinical target volume (CTV) (CTV-Gd) and the T2-MRI-based CTV (CTV-T2) were defined as the contrast-enhanced area on Gd-MRI and the high intensity area on T2-MRI, respectively. We defined CTV x mm (x=5, 10, 15, 20) as x mm outside the CTV. MET-PET-based CTV (CTV-MPET) was defined as the area of accumulation of MET-PET. We calculated the sensitivity and specificity of CTV-Gd and CTV-T2 following comparison with CTV-MPET, which served as the gold standard in this study.ResultsThe sensitivity of CTV-T2 5mm (98%) was significantly higher than CTV-T2 (87%), and there was no significant difference in the sensitivity between CTV-T2 5mm and CTV T2 10, 15, or 20mm. The sensitivity of CTV-Gd 20mm (97%) was lower than that of CTV-T2 5mm (98%).ConclusionsA margin of at least 5mm around the high intensity area on T2-MRI is necessary in the target volume delineation of recurrent glioblastoma for the coverage of MET-PET findings in re-radiation therapy planning.



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Quantitative analysis of the perimeniscal position of the inferior lateral genicular artery (ILGA): magnetic resonance imaging study.

Quantitative analysis of the perimeniscal position of the inferior lateral genicular artery (ILGA): magnetic resonance imaging study.

Surg Radiol Anat. 2018 Apr 24;:

Authors: Park J, Lee SS, Kim TW

Abstract
PURPOSE: The inferior lateral genicular artery (ILGA) passes around the lateral knee joint, adjacent to the lateral meniscus (LM). ILGA injuries in total knee arthroplasty or arthroscopic surgery can result in recurrent hemarthrosis or painful pseudoaneurysms. Detailed information about the perimeniscal position of the ILGA relative to the LM is necessary to avoid these complications.
METHODS: 3-T MR images of 100 knees (mean age 36.3 ± 11.2 years) were retrospectively reviewed. The perimeniscal area was divided into four regions: the anterior, middle, popliteal hiatus, and posterior zones. In each zone, the ILGA diameter, superoinferior position (assessed as the height of the ILGA from the LM base), and distance between the meniscocapsular junction and the ILGA were measured.
RESULTS: The distance between the ILGA and meniscocapsular junction was significantly smaller in the middle zone than in the other three zones (anterior 5.3 ± 0.8 mm, middle 1.4 ± 0.4 mm, popliteal hiatus 6.1 ± 1.0 mm, and posterior 5.6 ± 1.5 mm, p < 0.05). In the superoinferior position, the height of the ILGA was 3.4 ± 0.9 mm in the anterior zone, 0.4 ± 1.3 mm in the middle zone, - 1.9 ± 1.8 mm in the popliteal hiatus zone, and - 1.3 ± 4.3 mm in the posterior zone. When the LM bottom is the base, the ILGA was located superiorly in the anterior zone, close to the base in the middle zone, and inferiorly in the popliteal hiatus zone.
CONCLUSIONS: To avoid ILGA injury, close attention is necessary during surgical procedures involving the meniscocapsular junction of the LM, especially at the meniscal base in the middle zone.

PMID: 29694643 [PubMed - as supplied by publisher]



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Changes in the ADC of diffusion-weighted MRI with the oscillating gradient spin-echo (OGSE) sequence due to differences in substrate viscosities

Abstract

Purpose

Compared with the conventional pulsed gradient spin-echo (PGSE) sequence, diffusion-weighted imaging (DWI) with the oscillating gradient spin-echo (OGSE) sequence can shorten the diffusion time by changing the frequency. The purpose was to investigate whether n-alkanes are suitable as isotropic phantoms for estimating the diffusion coefficient with the OGSE sequence.

Materials and methods

We investigated changes in the apparent diffusion coefficient (ADC) due to differences in the viscosities of nine n-alkane phantoms with different numbers of carbon atoms from C8H18 to C16H34 using OGSE and PGSE sequences at 21 °C. Effective diffusion times of 4.3, 5.1, 6.5, 9.3, 20, 40, and 60 ms were used. The T2 relaxation times of each n-alkane phantom were measured using quantitative synthetic magnetic resonance imaging (MRI). Circular regions of interest were placed manually within the alkane phantoms on ADC and T2 maps.

Results

In each alkane phantom, changes in mean ADC values were almost constant with changes in diffusion times. Viscosities and ADC values showed inverse proportionality, as expected theoretically.

Conclusion

The ADC values of alkanes do not depend on diffusion times. The n-alkanes can be useful phantoms for assessing the accuracy of clinical protocols of DWI with the OGSE sequence.



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