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Background: Magnetic resonance imaging (MRI) is an emerging tool to assess organ-specific iron load in patients with transfusion dependent anemia., Objective: We performed MRI T2 star (T2*) assessment in 44 transfusion dependent patients to study the prevalence of cardiac and liver iron overload and the relationship of T2* measurement with various clinical and biochemical parameters., Result: Mean age of the study subjects was 19.9 years (range 8.8-32.3) and the mean cardiac T2* was 23.4 +/- 13.8 msec. Fifty percent of the subjects had abnormal cardiac T2* (below 20 msec). Cardiac T2* was not found to have any correlation with serum ferritin or liver T2*. Liver T2* value was abnormal in 79% of the subjects and it correlated inversely with both current and 12 months average serum ferritin (r = -0.44, P = 0.003; r = -0.46, P = 0.002). Clinical parameters including age, duration of transfusion, age starting iron chelation therapy, and ratio between transfusion volume and desferrioxamine dosage were not correlated with cardiac and liver T2*., Conclusion: We conclude that iron overload in heart and liver is common in our transfusion dependent patients. Liver T2* has inverse correlation with serum ferritin. Cardiac T2* does not have any correlation with the various clinical and biochemical parameters.

We studied the utility of pancreatic magnetic resonance imaging (MRI) in 72 thalassemia major patients (21 diabetic, 51 normoglycemic). Diabetic patients were significantly older (p<0.0001) and had smaller pancreas volume (p<0.0001). The two groups were comparable for ferritin and MRI-T2* heart, liver and pancreas. Pancreatic T2* signals were abnormal in 80% of both groups, and correlated with heart T2*. In normoglycemic patients, cardiac T2* and log-pancreatic T2* values correlated with homeostatic model assessments HOMA-B (beta cell reserve), HOMA-IR (insulin resistance) and fasting insulin/C-peptide levels. This suggested that improved chelation may improve beta cell reserve and prevent pancreatic atrophy.

Background: To assess the usefulness of air-inflated magnetic resonance colonography (MRC) in patients with incomplete conventional colonoscopy (CC)., Methods: From September 2001 to December 2004, 51 patients (25 male and 26 female, age range 32 to 85 years) with incomplete colonoscopy were recruited to have MRC performed. Half-fourier single short turbo spin echo (HASTE) axial, coronal, and three dimensional fat suppressed gradient echo sequence (VIBE) coronal images in both the prone and supine positions were performed for each patient. MRC was reviewed by two radiologists for detection of synchronous colonic lesion. The location and size of lesions were recorded and were compared with the findings of CC. Patients were managed according to the clinical situation and intraoperative findings were compared with MRC findings. Follow-up colonoscopy was performed in 29 patients. The follow-up colonoscopy findings were then compared with the MRC findings., Results: Forty-four patients had incomplete colonoscopy because of an obstructing tumor. The other seven patients had incomplete colonoscopy because of excessive bowel looping. Apart from one patient suffering from chronic obstructive airway disease with resulting nondiagnostic MRC, all other patients had MRC successfully performed. Each colon was divided into six bowel segments for analysis. All 300 segments were of diagnostic quality and were assessed by the MRC. MRC correctly identified all 44 obstructing tumors demonstrated by initial CC. Synchronous tumors in proximal colonic segments were identified in two patients by MRC. In addition, MRC identified two colonic tumors located in bowel segments inaccessible by CC because of excessive looping., Conclusions: MRC is useful for detection of colonic pathology and assessment of proximal colon in patients with colonic cancer after incomplete colonoscopy.

Background and Purpose: Magnetic resonance imaging (MRI) has been widely applied in detecting intracranial large artery stenosis, but there have been few validation studies to compare with histopathology. The aim of the postmortem study is to assess the accuracy of MRI in identifying middle cerebral artery (MCA) stenosis., Methods: We recruited, consecutively, Chinese postmortem autopsies in our hospital during 19 months. MRI was performed in the postmortem brains to scan the cross-sections of MCAs with barium expanding the artery lumen. The MCAs were then removed for histopathologic studies. With histopathology as a reference standard, the accuracy of MRI was evaluated, and the correlation between MCA stenosis identified by MRI and radiologically or histopathologically evident brain infarcts was investigated., Results: Seventy-six consecutive autopsies were recruited. The sensitivity and specificity of MRI in detecting more than 30% MCA stenosis were 38.6% and 92.2%, with a positive predictive value of 87.2% and negative predictive value of 52.2%, and the corresponding values of MRI in identifying more than 50% MCA stenosis were 57.1%, 90.8%, 50%, and 83.0%, respectively. Both more than 30% and more than 50% MCA stenosis identified by MRI were found to be associated with infarctions in the corresponding MCA territory (P= 0.001, odds ratio = 4.365, 95% CI: 1.684-11.313; and P= 0.039, odds ratio = 2.694, 95% CI: 1.139-6.377)., Conclusions: Our study demonstrates the agreement between ex vivo MRI and histopathology in identifying MCA stenosis, and the correlation between the MCA stenosis identified by MRI and radiologically or histopathologically evident brain infarcts.

The article presents a case study of 83-year old Chinese woman suffering from atrial fibrillation and dementia who was hospitalized due to cardiac arrest. Her magnetic resonance imaging scan before removal of middle cerebral artery (MCA) and after removal was performed for histological comparisons. The results showed hyper intense signal in left MCA and confirmed intraplaque hemorrhage.