Age dependency of cartilage magnetic resonance imaging T2 relaxation times in asymptomatic women

2004 ◽  
Vol 50 (9) ◽  
pp. 2820-2828 ◽  
Author(s):  
Timothy J. Mosher ◽  
Yi Liu ◽  
Qing X. Yang ◽  
Jing Yao ◽  
Ryan Smith ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Relaxation Times ◽  
Age Dependency ◽  
Resonance Imaging ◽  
T2 Relaxation ◽  
Asymptomatic Women

Evaluation of Relaxation Time Measurements by Magnetic Resonance Imaging

1987 ◽  
Vol 28 (3) ◽  
pp. 345-351 ◽  
Author(s):  
L. Kjær ◽  
C. Thomsen ◽  
O. Henriksen ◽  
P. Ring ◽  
M. Stubgaard ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Relaxation Time ◽  
Magnetic Resonance ◽  
Diffusion Processes ◽  
Relaxation Times ◽  
Gradient Field ◽  
Maximum Deviation ◽  
Resonance Imaging ◽  
T2 Relaxation ◽  
T1 And T2

Several circumstances may explain the great variation in reported proton T1 and T2 relaxation times usually seen. This study was designed to evaluate the accuracy of relaxation time measurements by magnetic resonance imaging (MRI) operating at 1.5 tesla. Using a phantom of nine boxes with different concentrations of CuSO4 and correlating the calculated T1 and T2 values with reference values obtained by two spectrometers (corrected to MRI-proton frequency=64 MHz) we found a maximum deviation of about 10 per cent. Measurements performed on a large water phantom in order to evaluate the homogeneity in the imaging plane showed a variation of less than 10 per cent within 10 cm from the centre of the magnet in all three imaging planes. Changing the gradient field strength apparently had no influence on the T2 values recorded. Consequently diffusion processes seem without significance. It is concluded that proton T1 and T2 relaxation times covering the majority of the biologic range can be measured by MRI with an overall accuracy of 5 to 10 per cent. Quality control studies along the lines indicated in this study are recommended.

PRIMARY MALIGNANT MELANOMA OF THE CEREBELLOPONTINE ANGLE

Neurosurgery ◽  
2006 ◽  
Vol 59 (6) ◽  
pp. E1336-E1336 ◽  
Author(s):  
Chima O. Oluigbo ◽  
Stephen R. Cooke ◽  
Peter A. Flynn ◽  
Kishor A. Choudhari
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Malignant Melanoma ◽  
Cerebellopontine Angle ◽  
Clinical Presentation ◽  
Relaxation Times ◽  
Primary Malignant Melanoma ◽  
Resonance Imaging ◽  
T2 Relaxation ◽  
T1 And T2

Abstract OBJECTIVE To present a rare case of a primary malignant melanoma of the central nervous system presenting as a cerebellopontine angle (CPA) tumor and to delineate aspects of the clinical presentation and magnetic resonance imaging scan characteristics that may suggest this unusual condition. CLINICAL PRESENTATION The clinical presentation consisted of a short duration of right-sided sensorineural hearing loss, facial weakness, and ataxia in a previously healthy man. Brain magnetic resonance imaging scans showed a right-sided CPA tumor exhibiting shortening of T1 and T2 relaxation times, but overall neuroradiological features were not consistent with any commonly occurring CPA tumors. INTERVENTION Gross total excision of the lesion was accomplished via a right suboccipital craniectomy. Histological examination revealed a malignant melanoma. A detailed search excluded extracranial primary melanoma. CONCLUSION Correlation of clinical and imaging findings offer the most important clues in the diagnosis of such unusual primary malignant tumors of the CPA. A history of rapid onset of audiovestibular symptoms, presence of facial palsy, and shortening of T1 and T2 relaxation times on magnetic resonance imaging scans should arouse the clinician's suspicions.

scholarly journals Method for Imaging the States of Water by Nuclear Magnetic Resonance in Low-water-containing Apple Bud and Stem Tissues

1993 ◽  
Vol 118 (5) ◽  
pp. 628-631 ◽  
Author(s):  
Merle M. Millard ◽  
Dehua Liu ◽  
Michael J. Line ◽  
Miklos Faust
Keyword(s):  
Magnetic Resonance Imaging ◽  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Malus Domestica ◽  
Woody Plants ◽  
Relaxation Times ◽  
Tissue Type ◽  
Proton Density ◽  
Resonance Imaging ◽  
T2 Relaxation

Magnetic resonance imaging estimates unreasonably high T2 times when creating T2 images in woody plants when tissues contain a limited amount of water. We developed a system to correct such images. Tissue distribution of proton density and states of water were determined by creating images of proton density and T2 relaxation times in summerdormant (paradormant) apple (Malus domestica Borkh.) buds. These images reveal that the proton density and water states obviously are not distributed uniformly in the bud and stem; but, the distribution of water depends greatly on the tissue type (bark, xylem, or meristem of the stem), and there are differences in the states of water even within the same tissue. At low proton density T2, calculated relaxation times were unreasonably high in tissues, with the exception of meristem of the shoot. In buds that were induced to grow and in which proton density was higher, T2 times appeared as expected. Variance of T2 times in tissues containing little water was 50 times higher than in those with a higher water content. Data with such high variance were excluded from the images; thus, the image was “corrected.” Corrected images of T2 times fit the distribution of water indicated by the proton density images well.

T1 and T2 relaxation times in schizophrenia as measured with magnetic resonance imaging

1991 ◽  
Vol 5 (3) ◽  
pp. 223-232 ◽  
Author(s):  
Nancy C. Andreasen ◽  
J.C. Ehrhardt ◽  
Victor W. Swayze ◽  
Gary Tyrell ◽  
Gregg Cohen ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Relaxation Times ◽  
Resonance Imaging ◽  
T2 Relaxation ◽  
T1 And T2

Assessment of T2 Relaxation Times for Normal Canine Knee Articular Cartilage by T2 Mapping Using 1.5-T Magnetic Resonance Imaging

2017 ◽  
Vol 30 (06) ◽  
pp. 391-397 ◽  
Author(s):  
Asami Matsui ◽  
Miki Shimizu ◽  
Brian Beale ◽  
Fumitaka Takahashi ◽  
Sinya Yamaguchi
Keyword(s):  
Magnetic Resonance Imaging ◽  
Articular Cartilage ◽  
Magnetic Resonance ◽  
T2 Mapping ◽  
Relaxation Times ◽  
Cartilage Thickness ◽  
Resonance Imaging ◽  
T2 Relaxation ◽  
Stifle Joint

Abstract Objectives This study aims to assess and compare the T2 relaxation times for articular cartilage of normal canine stifle joints in four regions by T2 mapping using a 1.5-T magnetic resonance imaging (MRI). Methods In vivo prospective study: 20 hindlimbs (left and right) from 10 normal healthy beagle dogs (n = 20). The region of interest (ROI) was subdivided into medial and lateral condyles of femoral cartilage (MF and LF, respectively) and medial and lateral condyles of tibial cartilage (MT and LT, respectively). The T2 relaxation times were assessed in regions where the cartilage thickness was greater than 0.5 mm. Results The median maximum cartilage thickness (mm) of the four ROI were 0.7 (range: 0.9–0.6), 0.6 (range: 0.7–0.5), 0.7 (range: 0.9–0.5) and 0.6 (range: 0.8–0.5) at MF, LF, MT and LT, respectively. The errors in the measurement (%) of the four ROI were 64.3 (range: 50.0–75.0), 75.0 (range: 64.3–90.0), 64.3 (range: 20.0–90.0) and 75.0 (range: 56.3–90.0) at MF, LF, MT and LT, respectively. The median T2 relaxation times (ms) for the articular cartilage of the four ROI were 70.2 (range: 57.9–87.9), 57.5 (range: 46.8–66.9), 65.0 (range: 52.0–92.0) and 57.0 (range: 49.0–66.2) at MF, LF, MT and LT, respectively. The inter-observer correlation coefficient (ICC, 2.1) for the T2 relaxation times of MF was 0.644. Clinical Significance This study offers useful information on T2 relaxation times for articular cartilage of the stifle joint using a 1.5-T MRI in normal dogs.

scholarly journals P010 Measurement of colonic mucosal content of biologics with the use of magnetic resonance imaging (MRI): A pilot study in patients with ulcerative colitis

2020 ◽  
Vol 14 (Supplement_1) ◽  
pp. S134-S135
Author(s):  
R Filip ◽  
P Bar ◽  
D Bartusik-Aebisher ◽  
D Aebisher
Keyword(s):  
Magnetic Resonance Imaging ◽  
Ulcerative Colitis ◽  
Pilot Study ◽  
Magnetic Resonance ◽  
Relaxation Times ◽  
Target Tissue ◽  
Resonance Imaging ◽  
T2 Relaxation ◽  
Drug Concentrations ◽  
T1 And T2

Abstract Background Anti-tumour necrosis factor antagonists (infliximab) as well as other molecules with different modes of action, including anti-integrin agents (vedolizumab), are currently used in patients with ulcerative colitis (UC Numerous studies have demonstrated a positive correlation between serum biologic drug concentrations and favourable therapeutic outcomes, whereas low or undetectable drug concentrations can lead to treatment failure. However, despite immunological issues, lack of and or loss of response may also be attributed to drug pharmacokinetics, of which penetration to the target tissue (colon wall) may play a crucial role Methods We used MRI to perform biochemical analyses of infliximab, adalimumab and vedolizumab concentrations testing the hypothesis that MRI relaxation time can be used to track antibodies in both mucosal biopsy samples and serum. All MR scans were performed with an Optima MR360 from General Electric Healthcare. To determine spin–lattice (T1) and spin–spin (T2) relaxation times, the Fast Spin Echo (FSE) sequence was used. Results The measured values of T1 relaxation times for infliximab, adalimumab, and vedolizumab were 2227 ± 35 ms, 2000 ± 22 ms and 1288 ± 15 ms, respectively. The obtained T2 relaxation times were 130 ± 11 ms, 90 ± 5, and 75 ± 10 ms, respectively. A decrease of both T1 and T2 values of 15 ± 3% are observed in serum from patients with ulcerative colitis. The values of infliximab and adalimumab were similar; the values of vedolizumab measurements in serum were about 50% lower. We find primary evidence that in T1 and T2 decreased in serum samples with ulcerative colitis and increase with the administration of infliximab, adalimumab and vedolizumab drugs. Samples of healthy tissue have T1 and T2 in the range of 2700 ± 5 ms and 150 ms ± 5 ms, respectively. A 30% decrease in T1 and T2 are observed for samples with ulcerative colitis. In this pilot study, we observed that values of T1 and T2 for tissues and serum that contain infliximab and adalimumab are similar, but vedolizumab shows a difference of about 30% when compared with infliximab and adalimumab. Conclusion MRI is an excellent method for quantitative and qualitative measurements of drug content in tissues and biological fluids. This is an innovative use of magnetic resonance imaging to develop a methodology for imaging of drugs that act as contrast agents via interaction with water in serum and tissue.

Follow-up of regional myocardial T2 relaxation times in patients with myocardial infarction evaluated with magnetic resonance imaging

1990 ◽  
Vol 11 (2) ◽  
pp. 110-119 ◽  
Author(s):  
X. Hanno Krauss ◽  
Ernst E. van der Wall ◽  
Arnoud van der Laarse ◽  
Joost Doornbos ◽  
Albert de Roos ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Myocardial Infarction ◽  
Magnetic Resonance ◽  
Relaxation Times ◽  
Resonance Imaging ◽  
T2 Relaxation
Sign in / Sign up

Export Citation Format

Share Document