MRI for the determination of pituitary iron overload in children and young adults with beta-thalassaemia major.

Hypogonadism, resulting from iron-induced pituitary dysfunction, is the most frequently reported complication in patients with beta-thalassaemia major. The aim of this study was to evaluate pituitary Magnetic Resonance Imaging (MRI) signal intensity reduction, on T2*-weighted images, as a marker of pituitary iron overload. Thirty patients (13 females and 17 males, mean age: 16.6+/-4.1) with beta-thalassaemia major on conventional treatment and 13 healthy volunteers (7 females and 6 males, mean age: 11+/-4.51 years) were studied with T2*-weighted images of the anterior pituitary using a 1.5T unit. Four thalassaemic patients (2 females and 2 males) had clinical hypogonadism and required hormonal replacement treatment. Results revealed a statistically significant reduction of pituitary signal intensity in the thalassaemia group compared to controls (p<0.001). Moreover, hypogonadal patients had significantly decreased MRI values compared to thalassaemic patients without hypogonadism (p=0.017). Relatively decreased adeno-hypophyseal MRI signal intensity was recorded in pubertal thalassaemic patients. A significant negative correlation was observed between pituitary MRI values and age (r=-0.67, r(2)=0.443, p=0.001), whereas ferritin levels and pituitary MRI values were moderately correlated (r=-0.56, r(2)=0.32, p=0.08) in adult thalassaemic patients. In conclusion, pituitary MRI indices as measured on T2*-weighted images seem to reflect pituitary iron overload and could, therefore, be used for a preclinical detection of patients who are in greater danger of developing hypogonadism.

Four-year evaluation of myocardial and liver iron assessed prospectively with serial MRI scans in young patients with beta-thalassaemia major: comparison between different chelation regimens.

This study was conducted in order to assess myocardial and liver iron concentrations (LICs) using serial magnetic resonance imaging (MRI) scans in patients with beta-thalassaemia major, over a 4-yr period, and consequently to compare the effectiveness of different chelation regimens. Fifty children and young adults with beta-thalassaemia major (27 boys and 23 girls) were recruited (mean age: 14.74 +/- 3.67 yr). All patients underwent detailed clinical examination, electrocardiography, echocardiography, myocardial and liver MRI at the beginning of the study, 2 and 4 yr after. Additionally, serum ferritin levels were regularly measured and data regarding LICs assessed by percutaneous liver biopsy were available in 26 patients. Both myocardial and liver MRI values showed a moderate inverse correlation with age (r = -0.379, P < 0.001 and r = -0.376, P < 0.001, respectively). Liver MRI was better correlated with serum ferritin concentrations (r = -0.342, P < 0.001) than myocardial MRI (r = -0.186, P = 0.011). Liver MRI values were highly correlated with LICs derived from percutaneous liver biopsy (r = -0.863, P < 0.001), whereas myocardial MRI values did not correlate at all with measurements derived from echocardiography. Regarding iron chelation treatment, patients receiving combined therapy with deferiprone and deferoxamine (DFO) significantly reduced myocardial iron overload during the 4-yr study period, whilst patients in monotherapy with DFO showed a significant increase in LIC.

Correlative study of iron accumulation in liver, myocardium, and pituitary assessed with MRI in young thalassemic patients.

Clinical complications resulting from unevenly iron accumulation in individual organs of patients with beta-thalassemia major can affect both expectancy and quality of life. Magnetic resonance imaging (MRI) offers a quantitative, noninvasive, accurate method for estimating iron levels in various tissues, not easily accessible with other techniques. The aim of this study was to evaluate and correlate the level of iron accumulation in different organs (anterior pituitary, myocardium, and liver) assessed with MRI, in children and young adults with beta-thalassemia major. Thirty children and young adults (13 female and 17 male patients) with homozygous beta-thalassemia, treated conventionally, were studied with hepatic, myocardial, and hypophyseal MRI. For liver and myocardium, we calculated the natural logarithm of the signal-to-air ratio in flash 2-dimensional sequences with electrocardiogram gating, whereas for anterior pituitary, the signal intensity was measured in sagittal T2 sequences. All scans were performed within 3 months. In 13 patients, data regarding liver iron concentrations (LIC) assessed by percutaneous liver biopsy were available. The mean of serum ferritin concentrations for 1 year before scans was calculated for each patient. MRI values in myocardium and liver showed a significant negative correlation to age (r=-0.73 and -0.69, respectively). For pituitary MRI, a linear regression with age was recorded in patients over 14 years of age (r=-0.67), whereas a relatively increased signal intensity reduction was recorded in pubertal subjects. Mean serum ferritin concentrations ranged from 252 to 5872 mug/L with an average of 1525+/-1047 mug/L. No statistical significant correlation was noted between mean ferritin levels versus liver, pituitary, and cardiac MRI values (r=-0.49, -0.28, and -0.1, respectively). Mean LIC values assessed by percutaneous biopsy were 13.76+/-11.6 mg/g of dry tissue. A statistically significant negative correlation was observed between liver MRI readings and LIC determined by biopsy (r=-0.89). None of the 3 organs studied with MRI were significantly correlated to each other. Pituitary to liver MRI values and liver to myocardial MRI values were moderately correlated (r=0.34 and 0.42, respectively). Pituitary MRI was not correlated at all to myocardial MRI (r=-0.001). In conclusion, iron accumulation in thalassemic patients is a procedure progressing with age, which seems to act independently in different organs. MRI represents a reliable, noninvasive method for assessing iron overload in various tissues, non-easily accessible with other techniques. Regular scanning, to recognize preclinically excessive iron deposits and intensified chelation therapy, can prevent serious and fatal complications.

Primary intramural fibroma of the left ventricle with a late apparent symptomatology.

We report a case of a 13-year-old girl who was admitted to the emergency department with syncope. She had been diagnosed in infancy with a large intramural fibroma of the left ventricle, but had been free of any clinical symptoms during the last decade. The patient underwent a thorough and detailed clinical and imaging study. We discuss the contribution of new non-invasive imaging modalities to the diagnosis of primary cardiac tumours and focus on the dilemmas of the paediatrician concerning the management of cardiac fibromas.