Chin Shang Li

R2* magnetic resonance imaging of the liver in patients with iron overload

R2* magnetic resonance imaging (R2*-MRI) can quantify hepatic iron content (HIC) by noninvasive means but is not fully investigated. Patients with iron overload completed 1.5T R2*-MRI examination and liver biopsy within 30 days. Forty-three patients (sickle cell anemia, n = 32; beta-thalassemia major, n = 6; and bone marrow failure, n = 5) were analyzed: median age, 14 years, median transfusion duration, 15 months, average (+/-SD) serum ferritin 2718 plus or minus 1994 ng/mL, and average HIC 10.9 plus or minus 6.8 mg Fe/g dry weight liver. Regions of interest were drawn and analyzed by 3 independent reviewers with excellent agreement of their measurements (intraclass correlation coefficient = 0.98). Ferritin and R2*-MRI were weakly but significantly associated (range of correlation coefficients among the 3 reviewers, 0.41-0.48; all P < .01). R2*-MRI was strongly associated with HIC for all 3 reviewers (correlation coefficients, 0.96-0.98; all P < .001). This high correlation confirms prior reports, calibrates R2*-MRI measurements, and suggests its clinical utility for predicting HIC using R2*-MRI. This study was registered at www.clinicaltrials.gov as #NCT00675038.

Evaluation of a comprehensive transcranial doppler screening program for children with sickle cell anemia.

Although transcranial Doppler ultrasonography (TCD) screening is effective in identifying children with sickle cell anemia (SCA) who are at high risk of stroke, not all children are screened. In 2003, we instituted a comprehensive TCD screening program designed to screen all at‐risk children treated at our sickle cell center.

Sickle cell hepatopathy: clinical presentation, treatment, and outcome in pediatric and adult patients.

Standard diagnostic criteria and therapy are lacking for sickle cell hepatopathy, an uncommon complication of sickle cell disease. Here we propose diagnostic and therapeutic guidelines based on our experience and on reported cases.

Preservation of spleen and brain function in children with sickle cell anemia treated with hydroxyurea

Chronic organ damage is an insidious process in patients with sickle cell anemia (SCA). Although hydroxyurea prevents acute vaso‐occlusive events, its effects on the preservation of organ function remain undefined.

Clinical and Diagnostic Imaging Findings Predict Anesthetic Complications in Children Presenting with Malignant Mediastinal Masses

Background:u2002 The presence of a mediastinal mass in a child poses significant anesthesia‐related risks including death. To optimize outcome clinicians must be able to predict which patients are at highest risk of anesthetic complications.

Therapy preference and decision-making among patients with severe sickle cell anemia and their families&

Patients with severe sickle cell anemia (SCA) may benefit from therapeutic intervention with hydroxyurea (HU), chronic red cell transfusion (CT), or stem cell transplantation (SCT). Determination of best treatment is complicated by the tradeoff between each treatments risks and benefits and the lack of data comparing them to determine efficacy. We explored factors that influenced making decisions regarding interventions and examined the relations between treatment preference and health‐related quality of life (HRQOL).

Chronic Transfusion Therapy for Children With Sickle Cell Disease and Recurrent Acute Chest Syndrome

The objective was to study the effects of chronic transfusion therapy (CTX) on the prevention of new episodes of acute chest syndrome (ACS) in children with sickle cell disease (SCD) and recurrent or unusually severe ACS. A retrospective chart review was performed of patients given CTX for recurrent or severe ACS. Frequency, median severity score, and median hospital stay for ACS episodes were determined. Differences in these values before and during CTX were analyzed. Twenty-seven patients were identified. Before treatment, the ACS incidence was 1.3 episodes per patient-year; during treatment, it decreased to 0.1 episodes per patient-year (P < 0.0001). The median severity score for ACS episodes was 0.8 (range 0-5) before CTX and 0.5 (0-3) during CTX (P = 0.84). The median hospital stay was 5 days (range 3-15 days) before CTX and 3 days (2-7 days) during CTX (P = 0.38). CTX significantly reduces the incidence of ACS events among patients with a history of recurrent or severe episodes but does not significantly decrease their severity. The effectiveness of CTX should be prospectively compared with that of hydroxyurea and stem cell transplantation.

Natural History of Thyroid Nodules in Survivors of Pediatric Hodgkin Lymphoma

Survivors of Hodgkin lymphoma and other patients who receive neck irradiation are at increased risk of thyroid cancer. Ultrasonography provides an inexpensive and non‐invasive method of thyroid screening, but the clinical significance of thyroid nodules detected by ultrasound screening is uncertain.

White Race As a Risk Factor for Hypothyroidism After Treatment for Pediatric Hodgkin's Lymphoma

PURPOSEnHypothyroidism frequently occurs after treatment for pediatric Hodgkins lymphoma, but race has not been investigated as a risk factor for this delayed toxicity. The aim of this study was to determine whether race is an independent risk factor for hypothyroidism in survivors of pediatric Hodgkins lymphoma.nnnPATIENTS AND METHODSnTo identify differences between black and white patients in the development of hypothyroidism after treatment for Hodgkins lymphoma, we conducted a retrospective study of consecutively treated pediatric patients with newly diagnosed Hodgkins lymphoma treated at St Jude Childrens Research Hospital (Memphis, TN) from January 1980 through December 2002. Clinical or biochemical hypothyroidism was defined by an above normal thyroxine-stimulating hormone concentration or by the need for thyroid hormone replacement therapy.nnnRESULTSnThe 461 patients (388 white patients, 73 black patients) where followed for a median of 11.3 years (range, 1.8 to 24.9 years). Hypothyroidism developed in 196 (43%) of 461 patients after a median of 2.9 years (range, 0.7 to 11.3 years) after diagnosis of Hodgkins lymphoma. Hypothyroidism developed in 47% of white patients but in only 21% of black patients (hazard ratio = 2.7; 95% CI, 1.6 to 4.6). After adjusting for other risk factors for hypothyroidism (thyroid radiation dose, sex, and nodular sclerosis histology), the risk of hypothyroidism in white patients was 2.5 times (95% CI, 1.5 to 4.3 times) the risk in black patients (P < .001).nnnCONCLUSIONnWhite patients have a higher risk of hypothyroidism after neck irradiation for pediatric Hodgkins lymphoma than black patients.

Comparison of whole liver and small region-of-interest measurements of MRI liver R2* in children with iron overload

BackgroundMeasurement of liver MRI T2* and R2* is emerging as a reliable alternative to liver biopsy for the quantitation of liver iron content. A systematic investigation of the influence of the region-of-interest size and placement has not been conducted.ObjectiveTo compare small and whole liver region-of-interest (ROI) MRI R2* values to each other and to biopsy liver iron content in patients with iron overload.Materials and methodsForty-one iron-overloaded patients, ages 7–35xa0years, underwent biopsy for liver iron content quantitation and MRI for liver R2* measurement within 30xa0days. Three reviewers independently used small and whole liver ROIs to measure R2*. Inter-reviewer agreement was assessed with the intra-class correlation coefficient (ICC). Associations between R2* and liver iron content were investigated using Spearman’s rank-order correlation and Monte Carlo estimated exact P values.ResultsBiopsy liver iron content and small and whole liver ROI R2* measurements were strongly associated for all reviewers (all Pu2009<u20090.0001). Although inter-reviewer agreement was excellent for both ROI methods (ICCu2009=u20090.98–0.99), the small ROI technique more frequently led to inter-reviewer differences larger than 75xa0Hz, slightly higher R2* values, larger standard errors and greater range in values.ConclusionSmall and whole liver ROI techniques are strongly associated with biopsy liver iron content. We found slightly greater inter-reviewer variability in R2* values using the small ROI technique. Because such variability could adversely impact patient management when R2* values are near a threshold of iron chelation therapy, we recommend using a whole liver ROI.