scholarly journals Restrictive lung disease in β-thalassemia major is associated with myocardial iron overload

2021 ◽  
Author(s):  
Kate Chan ◽  
Chun Ting Au ◽  
Alex Wing Kwan Leung ◽  
Albert Li ◽  
Chi-kong Li ◽  
...  
Keyword(s):  
Relaxation Time ◽  
Lung Function ◽  
Iron Overload ◽  
Myocardial Iron ◽  
Pulmonary Dysfunction ◽  
Thalassaemia Major ◽  
T2 Relaxation Time ◽  
T2 Relaxation ◽  
Restrictive Lung Disease

Background: Pulmonary dysfunction has been reported in patients with β-thalassaemia major but data are conflicting and the association with iron overload remains unclear. Objectives: To determine the pattern of pulmonary dysfunction in patients with β-thalassaemia major and their associations with iron overload. Methods: Subjects with β-thalassaemia major were recruited for lung function assessment. Serum ferritin and magnetic resonance imaging (MRI) measurements of iron status of the myocardium and the liver were used as surrogate indexes of body iron content. A subgroup of this cohort provided data on the longitudinal progress of their lung function. Results: One hundred and one patients were recruited with a mean age of 25.1 years (SD 7.9 years). Thirty-eight (38%) and five (5%) had restrictive and obstructive lung function deficits, respectively. There was a significant correlation between MRI myocardial T2* relaxation time and forced vital capacity (r=0.291, p=0.048). Higher MRI cardiac T2* relaxation time was associated with lower risk of having restrictive lung function deficit (Odds ratio (OR): 0.94; 95% CI: 0.89-0.99; p=0.023) after adjusting for age, gender and BMI. Twenty-three subjects underwent lung function reassessment with a mean follow-up duration of 13 years. Overall, they did not demonstrate significant changes in pulmonary function over time, 3 patients who had normal lung function at baseline developed restrictive abnormality at follow-up. Conclusions: Restrictive lung disease is prevalent in patients with β-thalassaemia major, and the severity correlates with myocardial iron overload. Monitoring of lung function in this group of patients is important, particularly for those with iron overload.

scholarly journals Early T2 changes predict onset of radiographic knee osteoarthritis: data from the osteoarthritis initiative

2014 ◽  
Vol 74 (7) ◽  
pp. 1353-1359 ◽  
Author(s):  
Hans Liebl ◽  
Gabby Joseph ◽  
Michael C Nevitt ◽  
Nathan Singh ◽  
Ursula Heilmeier ◽  
...  
Keyword(s):  
Relaxation Time ◽  
Knee Osteoarthritis ◽  
Case Control ◽  
T2 Relaxation Time ◽  
T2 Relaxation ◽  
Knee Oa ◽  
Osteoarthritis Initiative ◽  
Nested Case Control ◽  
Radiographic Knee Osteoarthritis

ObjectiveTo evaluate whether T2 relaxation time measurements obtained at 3 T MRI predict the onset of radiographic knee osteoarthritis (OA).Materials and methodsWe performed a nested case–control study of incident radiographic knee OA in the Osteoarthritis Initiative cohort. Cases were 50 knees with baseline Kellgren–Lawrence (KL) grade of 0 that developed KL grade of 2 or more over a 4-year period. Controls were 80 knees with KL grade of 0 after 4 years of follow-up. Baseline T2 relaxation time measurements and laminar analysis of T2 in deep and superficial layers were performed in all knee compartments. The association of T2 values with incident OA was assessed with logistic regression and differences in T2 values by case–control status with linear regression, adjusting for age, sex, body mass index (BMI) and other covariates.ResultsBaseline T2 values in all compartments except the medial tibia were significantly higher in knees that developed OA compared with controls and were particularly elevated in the superficial cartilage layers in all compartments. There was an increased likelihood of incident knee OA associated with higher baseline T2 values, particularly in the patella, adjusted OR per 1 SD increase in T2 (3.37 (95% CI 1.72 to 6.62)), but also in the medial femur (1.90 (1.07 to 3.39)), lateral femur (2.17 (1.11 to 4.25)) and lateral tibia (2.23 (1.16 to 4.31)).ConclusionsThese findings suggest that T2 values assessed when radiographic changes are not yet apparent may be useful in predicting the development of radiological tibiofemoral OA.

T2 relaxation time study of iron overload in b-thalassemia

1998 ◽  
Vol 6 (1) ◽  
pp. 7-12 ◽  
Author(s):  
S. I. Mavrogeni ◽  
E. D. Gotsis ◽  
V. Markussis ◽  
N. Tsekos ◽  
C. Politis ◽  
...  
Keyword(s):  
Relaxation Time ◽  
Iron Overload ◽  
Time Study ◽  
T2 Relaxation Time ◽  
T2 Relaxation

T2 relaxation time study of iron overload in b-thalassemia

1998 ◽  
Vol 6 (1) ◽  
pp. 7-12 ◽  
Author(s):  
S MAVROGENI ◽  
E GOTSIS ◽  
V MARKUSSIS ◽  
N TSEKOS ◽  
C POLITIS ◽  
...  
Keyword(s):  
Relaxation Time ◽  
Iron Overload ◽  
Time Study ◽  
T2 Relaxation Time ◽  
T2 Relaxation

scholarly journals T1 and T2∗ relaxation time in the parcellated myocardium of healthy Taiwanese participants: A single center study

2020 ◽  
Author(s):  
Chih-Chien Tsai ◽  
Shu-Hang Ng ◽  
Yao-Liang Chen ◽  
Yu-Hsiang Juan ◽  
Chao-Hung Wang ◽  
...  
Keyword(s):  
Relaxation Time ◽  
T2 Relaxation Time ◽  
Single Center ◽  
T2 Relaxation ◽  
Single Center Study ◽  
T1 And T2 ◽  
Center Study

scholarly journals T2 Relaxation Time of Cartilage at MR Imaging: Comparison with Severity of Knee Osteoarthritis

Radiology ◽  
2004 ◽  
Vol 232 (2) ◽  
pp. 592-598 ◽  
Author(s):  
Timothy C. Dunn ◽  
Ying Lu ◽  
Hua Jin ◽  
Michael D. Ries ◽  
Sharmila Majumdar
Keyword(s):  
Relaxation Time ◽  
Mr Imaging ◽  
Knee Osteoarthritis ◽  
T2 Relaxation Time ◽  
T2 Relaxation

Textural and pore size analysis of carbonates from integrated core and nuclear magnetic resonance logging: An Arbuckle study

2015 ◽  
Vol 3 (1) ◽  
pp. SA77-SA89 ◽  
Author(s):  
John Doveton ◽  
Lynn Watney
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Relaxation Time ◽  
Magnetic Resonance ◽  
Pore Size ◽  
Relaxation Times ◽  
T2 Relaxation Time ◽  
T2 Relaxation ◽  
Nmr Logging ◽  
The Core ◽  
Nuclear Magnetic

The T2 relaxation times recorded by nuclear magnetic resonance (NMR) logging are measures of the ratio of the internal surface area to volume of the formation pore system. Although standard porosity logs are restricted to estimating the volume, the NMR log partitions the pore space as a spectrum of pore sizes. These logs have great potential to elucidate carbonate sequences, which can have single, double, or triple porosity systems and whose pores have a wide variety of sizes and shapes. Continuous coring and NMR logging was made of the Cambro-Ordovician Arbuckle saline aquifer in a proposed CO2 injection well in southern Kansas. The large data set gave a rare opportunity to compare the core textural descriptions to NMR T2 relaxation time signatures over an extensive interval. Geochemical logs provided useful elemental information to assess the potential role of paramagnetic components that affect surface relaxivity. Principal component analysis of the T2 relaxation time subdivided the spectrum into five distinctive pore-size classes. When the T2 distribution was allocated between grainstones, packstones, and mudstones, the interparticle porosity component of the spectrum takes a bimodal form that marks a distinction between grain-supported and mud-supported texture. This discrimination was also reflected by the computed gamma-ray log, which recorded contributions from potassium and thorium and therefore assessed clay content reflected by fast relaxation times. A megaporosity class was equated with T2 relaxation times summed from 1024 to 2048 ms bins, and the volumetric curve compared favorably with variation over a range of vug sizes observed in the core. The complementary link between grain textures and pore textures was fruitful in the development of geomodels that integrates geologic core observations with petrophysical log measurements.

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