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ABSTRACT: MR elastography is a new imaging tool capable of non-invasively assessing the viscoelastic properties of tissues. The clinical application of MR elastography in the diagnosis of prostate cancer remains to be elucidated.
To investigate the feasibility of MR elastography in the diagnosis of prostate cancer at 3.0T, and to assess the elasticity and viscosity of prostate cancer and benign prostatic disease.
Eight patients (63 ± 7.25 years old) with 12 foci of prostate cancer and 10 patients (59 ± 3.25 years old) with 14 foci of prostatitis in the peripheral zone were evaluated by MRE. Ten healthy volunteers (41 ± 4.32 years old) with 18 ROIs in the peripheral zone of the prostate were also assessed with MR elastography as a control group. The results were confirmed by histopathological findings. All examinations were performed on a 3.0T Philips Achieva scanner. MRE was implemented by transmitting low-frequency longitudinal mechanical waves of 100Hz into the prostate with a transducer placed above the pubic bones. The phase images were reconstructed to acquire viscoelastic mapping. T-test was used to compare the mean elasticity and viscosity of prostate cancer and prostatitis. A comparison of prostate cancer and healthy prostate tissue in elasticity was also evaluated. The correlation of elasticity and Gleason scores between prostate cancer and prostatitis were retrospectively analyzed with Pearson Correlation.
The mean elasticity and viscosity were significantly higher in the lesions with prostate cancer (6.55 ± 0.47 kPa, 6.56 ± 0.99 Pa.s, respectively) than in regions with prostatitis (1.99 ± 0.66 kPa, 2.13 ± 0.21 Pa.s). The difference between prostate cancer and prostatitis was statistically significant (t = 19.392, p < 0.01; t = 16.372, p < 0.01). The elasticity and viscosity of the healthy peripheral zone of prostate were 2.26 ± 0.45 kPa, 2.38 ± 0.54 Pa.s, respectively. There also was significant difference in elasticity between prostate cancer and normal peripheral zone (t = 25.136, p < 0.01). In addition, we observed a positive correlation between Gleason scores and elasticity of the prostate cancer (r = 0.913, P < 0.01) in this study.
MR elastography can be used to visualize the difference in stiffness between prostate cancer and benign prostatic disease. It is a new imaging method with potential in the diagnosis of prostate cancer.
Acta Radiologica 04/2011; 52(3):354-8. · 1.33 Impact Factor
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ABSTRACT: BackgroundBecause of the limitation of technique, there are few researches on regulating function of central hypothalamus by metabolism, especially the researches on real-time function.ObjectiveTo evaluate the response of hypothalamus to oral glucose tolerance test (OGTT) in different body-weighted subjects by using functional magnetic resonance imaging (fMRI) so as to investigate the relationship between the sensitivity of hypothalamus in glycoregulation and disturbance of carbohydrate metabolism.DesignPaired design.SettingDepartment of Radiology and Beijing Geriatrics Institute, Beijing Hospital, National Public Health Bureau.ParticipantsA total of twenty healthy volunteers were selected from Beijing Geriatrics Institute, National Public Health Bureau, including 10 subjects with obesity (5 males and 5 females; body mass > 28.0 kg/m2) and 10 subjects with normal body mass (5 males and 5 females; body mass from 18.5 to 23.9 kg/m2). All subjects gave written informed consent before participating in the study.MethodsfMRI study was performed on GE 1.5 T Signa Twinspeed Infinity with Excite. Each volunteer was ingested of glucose during the fMRI scan. T2* images were acquired using a single-shot gradient echo (EPI) technique. The parameters of EPI included: TR 3 000 ms, TE 40 ms, Flip angle 90°, field of view (FOV) 24 cm × 24 cm, thickness 5 mm, gap 0 mm, matrix 64 × 64, number of excitation 1. All 10 subjects with normal body mass underwent a repeat fMRI scan after consuming an equivalent amount of water without glucose on a separate day. The procedure for the fMRI scan with water intake was the same as for glucose ingestion. fMRI data were processed with Intensity Averaging Method.Main outcome measuresThe central response of hypothalamus and feedback orientation during OGTT in different body-weighted subjects.ResultsAn acute transient decrease of fMRI intensity in posterior inferior and anterior inferior of hypothalamus was observed in all subjects within 2 minutes after oral glucose intake. This decrease was followed by a recovery to the baseline. However, obese subjects had a delayed intensity decrease [(1.96±1.06) minutes vs. (1.04±0.71) minutes, t =2.14, P < 0.05] and longer recovery time [(26.62±7.35) minutes vs. (16.29±6.42) minutes, t =3.67, P < 0.01] as compared with normal body-weight subjects. Furthermore, decreased fMRI intensity was significant different from baseline intensity [(5.7±2.5)% vs. (14.3±5.5)%, t =2.56, P < 0.05] in obese subjects, but not in normal body-weight subjects. The area of hypothalamus in normal body-weight volunteers demonstrated no significant signal change before and after oral water ingestion (P > 0.05).ConclusionHypothalamus response to glucose loading is different in normal body-weighted and obese subjects. This suggests that fMRI is a useful tool to evaluate the central regulation of glucose metabolism.
Neural Regeneration Research. 01/2007;
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ABSTRACT: Objective: To evaluate the clinical significance of clinical staging and magnetic resonance imaging (MRI) staging for prostate cancer before radical prostatectomy. Methods: Thirty-two patients with
organ confined prostate cancer were reviewed to assess the accuracy of clinical staging and MRI staging to
correlate with pathological staging results after radical prostatectomy. Results: 33.3% (10/30) prostate
cancer patients with staging C and 3.3% (1/30) prostate cancer patients with staging D were diagnosed
by pathology after radical prostatectomy in 30 patients with prostate cancer with clinical staging B, and
36.7% (11/30) under staging; Only one patient was over staging in clinical staging C. 19.1% (4/21) prostate
cancer patients with staging C were diagnosed in 21 patients with prostate cancer and under staging with
MRI staging B; 11.1% (1/9) was over staging with MRI staging C. The clinical staging and MRI staging
had more correlation with pathological staging results (P=0.002), and PPV of the organ confined prostate
cancer by clinical staging and MRI staging were 63.3% and 80.9% respectively, and NPV of nonorgan
confined prostate cancer by clinical staging and MRI staging were 50% and 88.9% respectively. MRI stag-
ing was more specificity and accuracy than that of clinical staging to predict pathological staging results
before radical prostatectomy (P=0.023). Conclusion: The MRI staging was more accuracy than that of
clinical staging to predict pathological staging results in organ confined and nonorgan confined prostate
cancer before radical prostatectomy.
The Chinese-German Journal of Clinical Oncology 08/2004; 3(3):175-178.