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1.
Hatakeyama T Kawai N Nishiyama Y Yamamoto Y Sasakawa Y Ichikawa T Tamiya T 《European journal of nuclear medicine and molecular imaging》2008,35(11):2009-2017
Purpose The purpose of this prospective study was to clarify the individual and combined role of l-methyl-11C-methionine-positron emission tomography (MET-PET) and 3′-deoxy-3′-[18F]fluorothymidine (FLT)-PET in tumor detection, noninvasive grading, and assessment of the cellular proliferation rate in
newly diagnosed histologically verified gliomas of different grades.
Materials and methods Forty-one patients with newly diagnosed gliomas were investigated with MET-PET before surgery. Eighteen patients were also
examined with FLT-PET. MET and FLT uptakes were assessed by standardized uptake value of the tumor showing the maximum uptake
(SUVmax), and the ratio to uptake in the normal brain parenchyma (T/N ratio). All tumors were graded by the WHO grading system using surgical specimens, and the proliferation activity of the
tumors were determined by measuring the Ki-67 index obtained by immunohistochemical staining.
Results On semiquantitative analysis, MET exhibited a slightly higher sensitivity (87.8%) in tumor detection than FLT (83.3%), and
both tracers were 100% sensitive for malignant gliomas. Low-grade gliomas that were false negative on MET-PET also were false
negative on FLT-PET. Although the difference of MET SUVmax and T/N ratio between grades II and IV gliomas was statistically significant (P < 0.001), there was a significant overlap of MET uptake in the tumors. The difference of MET SUVmax and T/N ratio between grades II and III gliomas was not statistically significant. Low-grade gliomas with oligodendroglial components
had relatively high MET uptake. The difference of FLT SUVmax and T/N ratio between grades III and IV gliomas was statistically significant (P < 0.01). Again, the difference of FLT SUVmax and T/N ratio between grades II and III gliomas was not statistically significant. Grade III gliomas with non-contrast enhancement
on MR images had very low FLT uptake. In 18 patients who underwent PET examination with both tracers, a significant but relatively
weak correlation was observed between the individual SUVmax of MET and FLT (r = 0.54, P < 0.05) and T/N ratio of MET and FLT (r = 0.56, P < 0.05). Total FLT uptake in the tumor had a higher correlation (r = 0.89, P < 0.001) with Ki-67 proliferation index than MET uptake (r = 0.49, P < 0.01).
Conclusions PET studies using MET and FLT are useful for tumor detection in newly diagnosed gliomas. However, there is no complimentary
information in tumor detection with simultaneous measurements of MET- and FLT-PET in low grade gliomas. FLT-PET seems to be
superior than MET-PET in noninvasive tumor grading and assessment of proliferation activity in gliomas of different grades. 相似文献
2.
FET PET for the evaluation of untreated gliomas: correlation of FET uptake and uptake kinetics with tumour grading 总被引:1,自引:0,他引:1
Pöpperl G Kreth FW Mehrkens JH Herms J Seelos K Koch W Gildehaus FJ Kretzschmar HA Tonn JC Tatsch K 《European journal of nuclear medicine and molecular imaging》2007,34(12):1933-1942
Purpose Treatment and prognosis of gliomas depend on their histological tumour grade. The aim of the study was to evaluate the potential
of [18F]fluoroethyltyrosine (FET) PET for non-invasive tumour grading in untreated patients.
Methods Dynamic FET PET studies were performed in 54 patients who, based on MRI, were estimated to have low grade (LG; n = 20), intermediate (WHO II–III; n = 4) or high grade (HG; n = 30) tumours. For standard evaluation, tumour SUVmax and the ratio to background (SUVmax/BG) were calculated (sum image: 20–40 min). For dynamic evaluation, mean SUV values within a 90% isocontour ROI (SUV90) and
the SUV90/BG ratios were determined for each time frame to evaluate the course of FET uptake. Results were correlated with
histopathological findings from PET-guided stereotactic biopsies.
Results Histology revealed gliomas in all patients. Using the standard method a statistically significant difference (p = 0.001) was found between LG (n = 20; SUVmax/BG: 2.16 ± 0.98) and HG (n = 34; SUVmax/BG: 3.29 ± 1.06) gliomas (opt. threshold 2.58: SN71%/SP85%/area under ROC curve [AUC]:0.798), however, with a marked overlap
between WHO II to IV tumours. Time activity curves showed slight increase in LG, whereas HG tumours presented with an early
peak (10–20 min) followed by a decrease. Dynamic evaluation successfully separated LG from HG gliomas with higher diagnostic
accuracy (SN94%/SP100%/AUC:0.967).
Conclusions Based on the ratio-based method, a statistically significant difference was found between LG and HG gliomas. Due to the interindividual
variability, however, no reliable individual grading was possible. In contrast, dynamic evaluation allowed LG and HG gliomas
to be differentiated with high diagnostic power and, thus, should supplement the conventional method. 相似文献
3.
Pöpperl G Götz C Rachinger W Gildehaus FJ Tonn JC Tatsch K 《European journal of nuclear medicine and molecular imaging》2004,31(11):1464-1470
Purpose The prognosis of patients with recurrent gliomas depends on reliable and early diagnosis of tumour recurrence after initial therapy. In this context, magnetic resonance imaging (MRI) and computed tomography (CT) often fail to differentiate between radiation- and tumour-induced contrast enhancement. Furthermore, absence of contrast enhancement, or even of 18F-fluorodeoxyglucose uptake in PET, does not exclude recurrence. The aim of this study was to establish the diagnostic value of O-(2-[18F]fluoroethyl)-l-tyrosine (FET) PET in recurrent gliomas.Methods Fifty-three patients with glioma (primary grading: 27=WHO grade IV, 16=grade III, 9=grade II, 1=grade I) and clinically suspected recurrence underwent FET PET scans 4–180 months after different treatment modalities. For semiquantitative evaluation, maximal SUV (SUVmax) and mean SUV within 80% and 70% isocontour thresholds (SUV80/SUV70) were evaluated and the respective ratios to the background (BG) were calculated. PET results were correlated with MRI/CT, clinical follow-up or biopsy findings.Results All patients presented with FET uptake, of varying intensity, in the area of the primary tumour after initial therapy. In the 42 patients with confirmed recurrence, there was additional distinct focal FET uptake with significantly higher values compared with those in the 11 patients without clinical signs of recurrence and showing only low and homogeneous FET uptake at the margins of the resection cavity. With respect to tumour grading, there was a slight but non-significant increase from WHO II (SUVmax/BG: 2.53±0.28) to WHO III (SUVmax/BG: 2.84±0.49) and WHO IV (SUVmax/BG: 3.55±1.07) recurrence.Conclusion FET PET reliably distinguishes between post-therapeutic benign lesions and tumour recurrence after initial treatment of low- and high-grade gliomas. 相似文献
4.
Ishida Y Kimura A Nosaka M Kuninaka Y Takayasu T Eisenmenger W Kondo T 《International journal of legal medicine》2012,126(3):435-440
Immunohistochemical study combined with morphometry was carried out to examine the expression of cyclooxygenase-2 (COX-2)
using 60 human skin wounds of different ages: group I, 0–4 h (n = 11); II, 8 h–2 days (n = 21); III, 3–9 days (n = 14); and IV, 12–21 days (n = 14). In wound specimens aged 2 h to 2 days, anti-myeloperoxidase-positive neutrophils observed at the wound site expressed
immunopositive reaction to COX-2. In wound specimens of more than 3 days, CD68-positive macrophages as well as neutrophils
were positively immunostained with anti-COX-2. In group II, all 21 wound samples had COX-2-positive ratios of >40 %, and 15
out of them showed >50 %. In group III, only three wound samples with the postinfliction intervals of 3 days showed positive
ratios of 40–50 % and the remaining 11 cases less than 40 %. In groups I and IV, all 25 wound specimens had COX-2-positive
ratio of <40 %. With regard to the practical applicability with forensic safety, these observations suggested that a COX-2-positive
ratio of >40 % indicated a wound age of 8 h to 3 days. Moreover, COX-2-positive ratios, considerably exceeding a ratio of
50 %, indicate a wound age of 8 h to 2 days. Collectively, COX-2 would be a useful marker for the determination of early wound
age. 相似文献
5.
Schmidt D Gottwald U Langen KJ Weber F Hertel A Floeth F Felsberg J Reifenberger G Coenen HH Müller-Gärtner HW 《European journal of nuclear medicine》2001,28(7):855-861
3-[123I]Iodo-alpha-methyl-L-tyrosine (IMT) is employed clinically as a tracer of amino acid transport in brain tumours using single-photon emission tomography (SPET). This study investigates the role of IMT SPET in the non-invasive histological grading and prognostic evaluation of cerebral gliomas. The files of patients investigated by IMT SPET in our clinic between 1988 and 1996 were evaluated retrospectively. Complete follow-up was available for 58 patients with cerebral gliomas investigated by IMT SPET shortly after tumour diagnosis. Seventeen patients had low-grade gliomas (WHO grade II), 14 had anaplastic gliomas (WHO grade III) and 27 had glioblastomas (WHO grade IV). Thirty-six cases were primary tumours and 22 cases, recurrences. Maximal and mean tumour-to-brain (T/B) ratios of IMT uptake at the first IMT SPET investigation were related to histological grading and survival time. Patients with low-grade gliomas showed significantly longer survival than patients with high-grade (grade III or IV) tumours. Gliomas without contrast enhancement on computed tomography or magnetic resonance imaging scans were associated with longer patient survival than tumours with contrast enhancement. The T/B ratios of IMT SPET showed no differences in relation to histological grading [WHO grade II: 1.73+/-0.59; WHO grade III: 1.74+/-0.38; WHO grade IV: 1.59+/-0.35, (mean+/-SD, T/B ratios of mean tumour uptake)]. The median survival time of patients with a high T/B ratio on IMT SPET was not significantly different from that of patients with a low T/B ratio (T/B ratio <1.6, 14.8 months; T/B ratio > or =1.6, 13.0 months). Thus, no evidence could be found for a relationship between IMT uptake in cerebral gliomas and either histological grading or survival time. Nevertheless, IMT SPET constitutes a useful method for the detection of primary and recurrent gliomas, determination of tumour extent and individual follow-up. 相似文献
6.
S. Newman V. M. Haughton Z. Yetkin R. Breger L. F. Czervionke A. L. Williams K. C. Ho R. A. Papke A. A. Rimm M. E. Fischer G. A. Meyer R. Asleson 《European radiology》1993,3(1):49-52
The possibility that cerebral tumours may be graded by measuring T1 or T2 with magnetic resonance (MR) imaging was studied. A consecutive series of patients with subsequently verified gliomas was enrolled, and studied with MR. Patients who had prior surgical, chemotherapeutic or steroid treatment were excluded. Single slice multiple saturation recovery and multiple spin echo techniques were used to measure T1, T2 and proton density in the tumour. In 33 patients with cerebral gliomas there were 5 grade I, 12 grade II, 7 grade III and 9 grade IV. T1 and T2 values tended to be smaller in grade I gliomas than in grades II, III and IV gliomas. Relaxation parameters overlapped considerably in tumours with different grades. Proton density values did not show much change between different grades of gliomas. Relaxation parameters cannot be used to determine tumour grade reliably.
Correspondence to: S. Newman 相似文献
7.
Hellwig D Romeike BF Ketter R Moringlane JR Kirsch CM Samnick S 《European journal of nuclear medicine and molecular imaging》2008,35(1):24-31
Objectives Radioactive amino-acids accumulate in gliomas even with an intact blood-brain-barrier. L-3-[123I]-iodo-α-methyl-tyrosine (IMT) is well established for SPECT imaging of gliomas. Recently, we introduced p-[123I]-iodo-L-phenylalanine (IPA) for the characterisation of brain lesions. This study compares both tracers in glioma patients.
Methods Eleven patients with gliomas (1 WHO grade 1, 5 grade 2, 1 grade 3, 2 grade 4 gliomas, 1 unconfirmed upgrading and 1 post-therapeutic
non-neoplastic lesion) underwent SPECT imaging with IPA (early and delayed acquisitions at 30 min and 3 h) and IMT (early
only). Maximum tumour-to-brain ratios (TBR) were calculated using region-of-interest analysis to assess uptake of IMT and
IPA. Imaging results were compared to histopathological findings.
Results Early TBRs of IMT and IPA were strongly correlated (r = 0.828, p = 0.002). TBRs were higher for IMT than IPA (1.95±0.50 versus
1.79±0.42; p < 0.05), but independent from tumour cell density (p > 0.1). Visual interpretation by different observers was
more concordant for IMT-SPECT than IPA-SPECT (kappa 1.0 versus 0.774). No differences in early TBRs were observed between
low-grade and high-grade gliomas for IMT (1.97±0.53 versus 2.21±0.44, p > 0.5) or IPA (1.70±0.23 versus 2.21±0.56, p = 0.167)
with a trend to higher TBRs in low-grade tumours for IMT (p = 0.093). In contrast to the known wash-out of IMT, we observed
persistent accumulation of IPA in gliomas.
Conclusions IPA shows lower TBRs than IMT, especially in low-grade tumours, so IMT should be preferred for the delineation of low-grade
gliomas by SPECT imaging. Due to its prolonged retention, however, IPA remains promising for therapeutic use in gliomas after
labelling with I-131.
This work was supported by a grant from the “Deutsche Krebshilfe” (70-3024-He 1). 相似文献
8.
Kaminogo M Ishimaru H Morikawa M Ochi M Ushijima R Tani M Matsuo Y Kawakubo J Shibata S 《Neuroradiology》2001,43(5):353-363
Accurate neuroimaging grading of gliomas is useful for management, but techniques such as MRI and CT are not sufficiently
reliable. Necrosis is a consistent, decisive prognostic factor and the key diagnostic criterion for glioblastoma multiforme.
MR spectroscopy (MRS) allows noninvasive measurement of metabolites in brain tumours and mobile lipids reflect necrosis. However,
short echo-time (TE) spectroscopy has been required for reliable assessment of lipids, since their relaxation times are very
short. Recent advances have made it possible to perform short-TE MRS. We attempted to evaluate the significance of short TE
spectroscopy as part of routine imaging for diagnosis and grading of gliomas. We performed TE 30 ms MRS in 25 patients with
gliomas (grade II six; grade III three; grade IV, 16) and in 19 areas of healthy white matter using proton brain examination/single
voxel (PROBE/SV) and point-resolved spatially localised spectroscopy (PRESS). With short-TE spectroscopy, lipid signals were
detected in all 16 tumours of grade IV, one grade II (P = 0.0002) and none of grade III (P = 0.001). TE 136 ms MRS, carried out in 20 of these cases, showed lipid signals in only four of 14 grade IV tumours and in
none of the other six. N-acetylaspartate/choline (NAA/Cho) ratios were always more than 1.0 in healthy tissues and less than
1.0 in all but one of the gliomas. The mean creatine (Cr)/Cho ratio in each tumour grade was significantly lower than in the
healthy tissues. The mean Cr/Cho ratio was also significantly lower in grade IV than in grade II tumours (P < .0005). Considerable overlap in Cr/Cho ratio was observed between grade II and grades III and IV gliomas at long but less
so at short-TE MRS. We conclude that short-TE MRS with PROBE/SV and PRESS is of value in grading gliomas.
Received: 25 June 2000 Accepted: 1 September 2000 相似文献
9.
L. Rizzo S. Greco Crasto P. Garcia Moruno P. Cassoni R. Rudà R. Boccaletti M. Brosio R. De Lucchi C. Fava 《La Radiologia medica》2009,114(4):645-659
Purpose This study was undertaken to correlate apparent diffusion coefficient (ADC) and relative regional cerebral blood volume (rrCBV)
to histological findings in a large series of patients with primary or secondary brain tumours to evaluate diffusion-weighted
(DWI) and perfusionweighted (PWI) imaging in the characterisation of cerebral tumors.
Materials and methods Ninety-eight patients with cerebral tumours, 46 of which were primary (seven grade 0-I, nine low-grade gliomas, two gliomatosis
cerebri, nine lymphomas and 19 high-grade gliomas) and 52 secondary, underwent conventional magnetic resonance (MR) imaging
completed with DWI and dynamic contrast susceptibility PWI. Both ADC and rrCBV were calculated on a workstation by using Functool
2 software. Student’s t test was used to determine any statistically significant differences in the ADC and rrCBV values.
Results Seventeen of 98 tumours were cystic or necrotic (12/17 hypointense and 5/17 hyperintense on DWI); the ADC value of hyperintense
cystic areas was 0.97±0.23×10−3 mm2/s. The ADC value of solid tumours varied between 0.64 and 3.5×10−3 mm2/s. The rrCBV value was 1.4 (σ 0.66) in low-grade gliomas; 1.22 (σ 0.25) in lymphomas; 4.5 (σ 0.85) in grade III gliomas;
3.18 (σ 1.26) in grade IV gliomas and 2.53 (σ 1.6) in metastases.
Conclusions DWI has an important role in the differential diagnosis of cystic cerebral masses but not in tumour characterisation. PWI
is helpful in differentiating high-from low-grade gliomas and lymphomas from high-grade gliomas.
相似文献
10.
Sonali S. De Silva Geoffrey S. Payne Veronica A. Morgan Thomas E. J. Ind John H. Shepherd Desmond P. J. Barton Nandita M. deSouza 《European radiology》2009,19(8):2041-2048
To investigate epithelial and stromal metabolite changes in cervical intraepithelial neoplasia (CIN) and cervical cancer in
vivo and correlate findings with MR spectroscopy of tissue samples. Forty-seven women (19 with CIN, 28 with cervical cancer)
underwent endovaginal MR at 1.5 T with T2-W and localised 2D MR spectroscopic imaging (PRESS, TR = 1,500 ms, TE = 135 ms).
tCho, 2 ppm and -CH2 lipid peaks were measured in epithelial (>50% epithelium, no tumour), stromal (>50% stroma, no tumour) and tumour (>30% tumour)
voxels. Unsuppressed water signal from the same voxel provided a concentration reference. 1H HR-MAS MR spectra were acquired from tissue in 37 patients (11.74 T, pulse-acquire and cpmg sequences, with water pre-saturation).
Analysable data from 17 CIN and 25 cancer patients showed significant increases in tCho (p = 0.03) and 2 ppm (p = 0.007) in
tumour compared with epithelial voxels from CIN patients, but not with epithelial voxels from cancer patients. No significant
differences were seen in stroma from cancer compared with CIN patients. Differences in -CH2 lipids were not significant between groups. There was no significant correlation between in vivo and ex vivo tCho or -CH2 lipids. Estimated in vivo concentrations of tCho and 2 ppm resonances increase in tumour and adjacent epithelium in progression
from CIN to cervical cancer.
This work was supported by Cancer Research UK (CUK) grant nos. C1353/A5408 and C1060/A808. 相似文献
11.
Max-Ludwig Schäfer Martin H. Maurer Michael Synowitz Joost Wüstefeld Tim Marnitz Florian Streitparth Edzard Wiener 《European radiology》2013,23(10):2846-2853
Objective
To evaluate the diagnostic potential of a multi-factor analysis of morphometric parameters and signal characteristics of brain tumours and peritumoural areas for distinguishing WHO-grade II and III gliomas at magnetic resonance imaging (MRI).Methods
MR examinations of 108 patients with histologically proven World Health Organization (WHO) grade II and III gliomas were included. Morphological criteria and MR signal characteristics were evaluated. The data were subjected to a multifactorial logistic regression analysis to differentiate between grade II and grade III gliomas. The discriminatory power was assessed by receiver operating characteristic (ROC).Results
Logistic regression analysis showed that WHO grade II and III can be distinguished based on contrast enhancement, cortical involvement, margin of the enhancing lesion and maximum diameter (width and length) of the peritumoural area (the so-called tumour infiltration zone). With the final model of logistic regression analysis and with the cut-off value?≥?0.377, WHO grade III glioma is predicted with a sensitivity of 71.0 % and a specificity of 80.4 %.Conclusion
Measurement of maximum diameter of peritumoural area, contrast enhancement as well as cortical involvement and the margin of the contrast-enhancing lesion can be used easily in clinical routine to adequately distinguish WHO grade II from grade III gliomas.Key Points
? MRI offers new information concerning WHO-grade II and III gliomas. ? The differentiation between such tumour grades is important for therapeutic decisions. ? We assessed differences in enhancement, cortical involvement, margins and peritumoural appearances. ? WHO grade III gliomas can be predicted with reasonable sensitivity and specificity. 相似文献12.
Jochen B. Bader Samuel Samnick Jean-Richard Moringlane Wolfgang Feiden Andrea Schaefer Stefanie Kremp Carl-Martin Kirsch 《European journal of nuclear medicine and molecular imaging》1999,26(2):144-151
. Based on the results of stereotactic biopsy, we evaluated in a prospective fashion the efficiency of l-3-[123I]iodo-α-methyltyrosine-single-photon emission tomography (SPET) and [18F]fluorodeoxyglucose (FDG) positron emission tomography (PET) in the detection and grading of recurrences in patients previously
treated for gliomas. The patient population comprised 30 individuals, nine with astrocytomas of grade II, ten with astrocytomas
of grade IV, three with oligoastrocytomas of grade II, six with oligodendrogliomas of grade II and two with anaplastic oligodendrogliomas
of grade III) suspected of recurrence and scheduled for further treatment. IMT SPET data were acquired using either by dual-or
a triple-headed SPET camera, Multispect 2/3. FDG uptake was measured with an ECAT ART PET camera. Two independent observers
classified PET and SPET images as positive or negative for tumour tissue. Uptake of FDG and IMT was evaluated visually and,
in the case of IMT, also quantitatively by calculating the ratios between tracer accumulation in the lesion and the unaffected
contralateral regions of reference using the region of interest (ROI) technique. The PET and SPET results were compared with
the histopathological findings obtained either by stereotactic biopsy or in one case by open surgery. Glucose metabolism and
amino acid uptake of recurrences of brain tumours as assessed by FDG-PET and IMT-SPET correlated highly with the histopathological
findings. Based on the histopathological data, FDG-PET and IMT-SPET findings confirmed recurrence in all cases of high-grade
gliomas (IV). A difference could be demonstrated in low-grade (II–III) tumour recurrences. True-positive IMT-SPET results
were found in 86% of grade III and 75% of grade II recurrences, whereas FDG-PET yielded a sensitivity of 71% in tumours of
grade III and 50% in those of grade II. With respect to the grade of malignancy of brain tumours at recurrence, IMT-SPET,
in contrast to FDG-PET, does not permit adequate in vivo grading of non-mixed brain tumours of astrocytic or oligodendroglial
origin. However, in this study FDG-PET did not permit discrimination between upgrading of low-grade oligoastrocytomas (II)
into anaplastic oligodendrogliomas (III) and upgrading into glioblastomas (IV) The results of this study indicate that FDG-PET
and IMT-SPET are equivalent to stereotactic biopsy in their ability to identify high-grade tumours at recurrence. IMT-SPET
proved to be superior to FDG-PET in confirming low-grade recurrences. In the case of suspected progression of the grade of
malignancy in ordinary gliomas, FDG-PET correlated significantly with the histopathological grading, whereas IMT-SPET did
not. However, tumour grading by FDG-PET has a limitation in mixed brain tumours in that it is not possible to discriminate
between progression of the oligo- versus the astrocytic tumour entity. In this case histopathological evaluation of the tumour
grade remains necessary.
Received 6 August and in revised form 2 November 1998 相似文献
13.
Fushimi Y Miki Y Urayama S Okada T Mori N Hanakawa T Fukuyama H Togashi K 《European radiology》2007,17(11):2921-2925
Discrepancies exist in the literature regarding contrast between gray and white matter on spin-echo (SE) T1-weighted MR imaging
at 3 T. The present study quantitatively assessed differences in gray matter-white matter contrast on both single- and multi-slice
SE T1-weighted imaging between 3 and 1.5 T. SE T1-weighted sequences with the same parameters at both 3 and 1.5 T were used.
Contrast-to-noise ratio (CNR) between gray and white matter (CNRGM-WM) was evaluated for both frontal lobes. To assess the effects of interslice gap, multi-slice images were obtained with both
0 and 25% interslice gap. Single-slice CNRGM-WM was higher at 3 T (17.66 ± 2.68) than at 1.5 T (13.09 ± 2.35; P < 0.001). No significant difference in CNRGM-WM of multi-slice images with 0% gap was noted between 3 and 1.5 T (3T, 8.61 ± 2.55; 1.5T, 7.43 ± 1.20; P > 0.05). Multi-slice CNRGM-WM with 25% gap was higher at 3T (12.47 ± 3.31) than at 1.5 T (9.73 ± 1.37; P < 0.001). CNRGM-WM reduction rate of multi-slice images with 0% gap compared with single-slice images was higher at 3T (0.47 ± 0.13) than at
1.5 T (0.38 ± 0.09; P = 0.02). CNRGM-WM on single-slice SE T1-weighted imaging and CNRGM-WM on multi-slice images with 25% interslice gap were better at 3 T than at 1.5 T. The influence of multi-slice imaging on CNRGM-WM was significantly larger at 3T than at 1.5 T.
This study was supported in part by a Health and Labour Sciences Research Grant of Japan
Yasutaka Fushimi and Yukio Miki equally contributed to the study. 相似文献
14.
Souvatzoglou M Grosu AL Röper B Krause BJ Beck R Reischl G Picchio M Machulla HJ Wester HJ Piert M 《European journal of nuclear medicine and molecular imaging》2007,34(10):1566-1575
Purpose Hypoxia is an important negative prognostic factor for radiation treatment of head and neck cancer. This study was performed
to evaluate the feasibility of use of 18F-labelled fluoroazomycin arabinoside ([18F]FAZA) for clinical PET imaging of tumour hypoxia.
Methods Eleven patients (age 59.6 ± 9 years) with untreated advanced head and neck cancer were included. After injection of approximately
300 MBq of [18F]FAZA, a dynamic sequence up to 60 min was acquired on an ECAT HR+ PET scanner. In addition, approximately 2 and 4 h p.i.,
static whole-body PET (n = 5) or PET/CT (n = 6) imaging was performed. PET data were reconstructed iteratively (OSEM) and fused with CT images (either an external CT
or the CT of integrated PET/CT). Standardised uptake values (SUVs) and tumour-to-muscle (T/M) ratios were calculated in tumour
and normal tissues. Also, the tumour volume displaying a T/M ratio >1.5 was determined.
Results Within the first 60 min of the dynamic sequence, the T/M ratio generally decreased, while generally increasing at later time
points. At 2 h p.i., the tumour SUVmax and SUVmean were found to be 2.3 ± 0.5 (range 1.5–3.4) and 1.4 ± 0.3 (range 1.0–2.1), respectively. The mean T/M ratio at 2 h p.i. was
2.0 ± 0.3 (range 1.6–2.4). The tumour volume displaying a T/M ratio above 1.5 was highly variable. At 2 h p.i., [18F]FAZA organ distribution was determined as follows: kidney > gallbladder > liver > tumour > muscle > bone > brain > lung.
Conclusion [18F]FAZA PET imaging appears feasible in head and neck cancer patients, and the achieved image quality is adequate for clinical
purposes. Based on our initial results, [18F]FAZA warrants further evaluation as a hypoxia PET tracer for imaging of cancer. 相似文献
15.
Introduction Despite the high grade of standardisation of study protocols, there is still room for variability among the centres in specific
treatment aspects. We evaluated the treatment risk in stent-protected angioplasty of the carotid versus endarterectomy (SPACE)
associated with the specific patient enrolment rates of the centres.
Materials and methods The analysed endpoints were ipsilateral stroke or death [primary outcome event (pOE)] and any stroke or death [secondary outcome
event (sOE)] until 30 days after treatment. A binary logistic regression analysis with random effects was performed separately
for each treatment arm. The centres were secondarily categorised in three classes: I) ≥25 patients enrolled, II) ten to 24
patients and III) <10 patients and a hierarchic log linear model was fitted to test the three-way interaction of treatment,
number of patients per class and outcome.
Results The random effects logistic regression analysis in the carotid artery stenting (CAS) arm proved a significant increase in
pOE with decreasing number of patients enrolled (−0.0190 ± 0.0085, p = 0.025, deviance 35.7 with 32 df), whereas no such effect was found in the carotid endartectomy (CEA) arm (−0.010 ± 0.008, p = 0.24, deviance 39.78 with 32 df). In the log linear model, there was a significant interaction between treatment, number of patients per centre and sOE (p = 0.023). The odds ratios for sOE in the enrolment classes (CAS vs. CEA) were 0.98 (95% CI 0.50–1.94, p = 0.95) for class I, 1.13 (95% CI 0.47–2.77, p = 0.77) for class II and 11.56 (95% CI 1.40–253.45, p = 0.01) for class III centres.
Conclusion Despite rigorous standardisation and quality requirements for operator qualification, there seemed to be a decrease in complication
rate with increasing patient enrolment numbers in the CAS arm while this signal could not be detected in the CEA arm of SPACE. 相似文献
16.
Nonoperative management of blunt splenic injury is the treatment of choice in hemodynamically stable patients. Detection of
vascular injury by multidetector CT (MDCT) is the most significant factor predicting the need for endovascular treatment.
This study evaluated the timing of the appearance of vascular lesions during angiography. Images from 20 patients embolized
for pseudoaneurysms (PSA) were evaluated. Angiograms were reviewed for phase and timing of PSA. Admission MDCT was reviewed
for injury grade and PSA. Initial MDCT evaluation indicated grade III and IV splenic injuries in 9 and 11 patients, respectively.
PSA was seen on MDCT in 14/20 (70%) patients. Time from opacification of the aorta to vascular injury was 1.32 s for arterial
phase injuries compared with 2.05 s for postcapillary injuries (P = 0.097). Angiography demonstrated 15 vascular injuries during the arterial and 5 in the venous phase. Of injuries seen during
arterial phase angiography, 10/15 (66%) were identified on MDCT. Of the five injuries that exhibited postcapillary-phase findings,
4/5 (80%) demonstrated PSA (P = 0.5). Vascular lesions are a better indicator of subsequent clinical deterioration than splenic injury grade. PSAs are
more frequently seen in postcapillary vascular injuries than arterial phase lesions with the current timing of MDCT. In a
subset of patients in whom splenic injury grades III and IV warrant angiography, PSAs are not initially demonstrated on MDCT.
Therefore, alteration of MDCT timing parameters to better correlate with arterial phase angiography may improve initial diagnosis
of vascular injury. 相似文献
17.
Cremonesi M Ferrari M Bartolomei M Orsi F Bonomo G Aricò D Mallia A De Cicco C Pedroli G Paganelli G 《European journal of nuclear medicine and molecular imaging》2008,35(11):2088-2096
Introduction Radioembolisation with 90Y-microspheres is a new locoregional treatment of hepatic lesions, usually applied as single cycle. Multi-cycle treatments
might be considered as a strategy to improve the risk-benefit balance. With the aim to derive suitable information for patient
tailored therapy, available patients’ dosimetric data were reviewed according to the linear–quadratic model and converted
into biological effective dose (BED) values. Single vs. multi-cycle approaches were compared through radiobiological perspective.
Materials and methods Twenty patients with metastatic lesions underwent radioembolisation. The 90Y-administered activity (AA) was established in order to respect a precautionary limit dose (40 Gy) for the non-tumoral liver
(NTL). BED was calculated setting α/β = 2.5 Gy (NTL), 10 Gy (tumours); T
1/2,eff = T
1/2,phys = 64.2 h; T
1/2,rep = 2.5 h (NTL), 1.5 h (tumours). The BED to NTL was considered as a constraint for multi-cycle approach. The AA for two cycles
and the percent variations of AA, tumour dose, BED were estimated.
Results In one-cycle, for a prescribed BED to NTL of 64 Gy (NTL dose = 40 Gy), AA was 1.7 (0.9–3.2) GBq, tumour dose was 130 (65–235)
Gy, and tumour BED was 170 (75–360) Gy. Considering two cycles, ∼15% increase was found for AA and dose to NTL, with unvaried
BED for NTL. Tumour dose increase was 20 (10–35) Gy; tumour BED increase was 10 (3–11) Gy. In different protocols allowing
80 Gy to NTL, the BED sparing estimated was ∼50 Gy (two cycles) and 65 Gy (three cycles).
Conclusions From a radiobiological perspective, multi-cycle treatments would allow administering higher activities with increased tumour
irradiation and preserved radiation effects on NTL. Trials comparing single vs. multiple cycles are suggested. 相似文献
18.
Yen TC See LC Lai CH Tsai CS Chao A Hsueh S Hong JH Chang TC Ng KK 《European journal of nuclear medicine and molecular imaging》2008,35(3):493-501
Purpose We sought to identify prognostic factors—including positron emission tomography (PET) parameters—in patients with previously
untreated squamous carcinoma of the uterine cervix and MRI- or CT-defined pelvic or para-aortic lymph node (PLN or PALN) metastasis.
Materials and methods Patients with untreated squamous cell cervical cancer and PLN or PALN metastasis detected by CT/MRI were enrolled. FDG-PET
scans were performed for primary staging. Prognostic variables were investigated by univariate and multivariate analyses.
Five-year recurrence-free and 5-year overall survivals (RFS and OS) were evaluated using the Kaplan–Meier method.
Results A total of 70 patients [54 patients with International Federation of Gynecology and Obstetrics (FIGO) stage I or II, and 16
patients with stage III or IV] were eligible. Follow-up ranged from 26.1 to 71.6 months. In multivariate analysis, FIGO stage
≥III (5-year RFS, p = 0.008; 5-year OS, p = 0.008) was a significant prognostic factor for both RFS and OS. In addition, SUVmax for PALN (dichotomized by 3.3) was significantly associated with OS (p = 0.012) and marginally with RFS (p = 0.078). The presence of SUVmax ≥ 3.3 at PALN or FIGO stage ≥III were significantly associated with both recurrence [5-year RFS; HR = 4.52, 95% confidence
interval (CI) = 1.73–11.80] and death (5-year OS; HR = 6.04, 95% CI = 1.97–18.57).
Conclusion SUVmax ≥ 3.3 for PALN and FIGO stage ≥III were significant adverse factors in patients with primary squamous cervical carcinoma
and PLN or PALN metastasis detected by CT/MRI.
This study was presented in part at the 42nd American Society of Clinical Oncology Annual Meeting, 2006, Atlanta, GA, USA. 相似文献
19.
Juan CJ Chen CY Jen YM Liu HS Liu YJ Hsueh CJ Wang CY Chou YC Chai YT Huang GS Chung HW 《European radiology》2009,19(1):94-102
We aimed to quantitatively investigate the alteration of parotid perfusion after irradiation using dynamic contrast-enhanced
magnetic resonance imaging (DCE-MRI) based on a two-compartment tracer kinetic model. This study enrolled 19 patients (53.2 ± 14.9 years)
treated by head and neck radiotherapy and 19 age-relevant and sex-matched subjects as a control group. Perfusion parameters
(K
el
, k
21 and A) of parotid glands were analyzed based on the Brix model from T1-weighted DCE-MRI. Suitability of the Brix model was evaluated
via Monte Carlo simulation for the goodness-of-fit. Analysis of nonlinear goodness-of-fit showed that the Brix model is appropriate
in evaluating the parotid perfusion (R2 = 0.938 ± 0.050). The irradiated parotid glands showed significantly lower K
el
(P < 0.0005) and k
21
(P < 0.05) and consequently significantly higher value of peak enhancement (P < 0.0005) and time-to-peak (P < 0.0005) compared with non-irradiated ones, suggestive of gradual and prolonged accumulation and delayed wash-out of contrast
agent due to increased extracellular extravascular space and decreased vascular permeability in the irradiated glands. Linear
regression analysis showed dose-dependent perfusion changes of the irradiated parotid glands. We conclude that quantitative
DCE-MRI is a potential tool in investigating parotid gland perfusion changes after radiotherapy. 相似文献
20.
Zhang N Zhang L Qiu B Meng L Wang X Hou BL 《Journal of magnetic resonance imaging : JMRI》2012,36(2):355-363