Infected bilomas and hepatic artery thrombosis in infant recipients of liver transplants. Interventional radiology and medical therapy as an alternative to retransplantation

Fifteen children less than 12 kg in weight underwent transplantation of the liver for biliary atresia; eight survived. Five of the eight survivors had thrombosis of the hepatic artery without portal vein thrombosis. Three of the five patients with hepatic artery thrombosis developed infected bilomas, which were drained percutaneously under ultrasonographic (US) or computed tomographic (CT) guidance. Concurrent therapy with antibiotics and hyperoxygenation resulted in resolution of these intrahepatic collections. Although it had been thought that thrombosis of the hepatic artery most often results in necrosis of the graft and requires retransplantation, the five patients in this study survived without retransplantation. Diagnosis of hepatic artery thrombosis was achieved with the use of Doppler US in four cases, CT in four cases, and angiography in two cases. Duplex Doppler US is the preferred imaging modality.     

Radiation enteritis

The frequent use of radiotherapy for abdominal and pelvic malignancies results in an increased risk of radiation enteritis. An increased understanding of the tissue response and the clinical features of radiation enteritis has led to advances in the prevention and management of this condition. Importantly, improvements in the delivery of radiotherapy, including techniques to reduce the amount of exposed small intestine in the radiation field, represent a critical strategy for prevention. Data indicate that radioprotectant agents have the potential to reduce intestinal mucosal injury and may be beneficial in reducing both acute and chronic side effects of radiotherapy.     

MR imaging of laser-tissue interactions

A new application of magnetic resonance (MR) imaging to map the spatial and temporal distribution of the effects of Nd:YAG lasers on tissues was studied. The temperature dependence of MR relaxation mechanisms and the high sensitivity of MR to changes in the mobility and distribution of tissue water make it particularly suitable for the demonstration and control of thermal energy deposition in tissues. In heterogeneous tissues, MR imaging does not follow changing temperatures directly because even in the case of reversible thermal interactions, there is a hysteresis in the dynamic relationship between MR signal intensity and temperature. Appropriate matching of the laser and MR pulse sequences can, however, optimize the detection of relatively small laser energy deposition, and reversible and irreversible tissue changes can be distinguished. There is a potential for the integration of MR imaging and lasers for three-dimensional control and monitoring of laser-tissue interactions.     

Three-dimensional reconstruction of the human central sulcus reveals a morphological correlate of the hand area

One way to improve our understanding of cortical anatomy is to visualize the three-dimensional (3D) shape of the cerebral sulci which is normally hidden. Here, we reconstructed the 3D morphology of the central sulcus (CS) in 17 normal subjects, using conventional magnetic resonance images and dedicated software. We found that the 3D morphology was remarkably consistent in all central sulci. Our analyses revealed three different regions (upper, middle and lower), which were easily identifiable by morphological criteria and sharply interconnected in the reconstructed CS. These morphological regions appear to have a strong functional significance, since the middle region corresponded precisely to the 'hand area', as verified by hand vibration positron emission tomography activation studies in eight cases. These data suggest that the 3D anatomy of the cerebral cortex may facilitate sulcal recognition, and sulcal subdivision into smaller morphological elements, bearing remarkable relationships with functional cortical maps.      

Clinical features of renal diseases in South-East Asia

Summary: The renal diseases in South-East Asia are similar to other parts of the world (i.e. glomerulonephritis, diabetes mellitus, HT, obstructive uropathy, adult-onset polycystic kidney disease, nephrolithiasis and tubulointerstitial diseases). IgA nephropathy with haematuria is most common in Singapore, while IgM nephropathy with nephrotic syndrome is common in Thailand. Lupus nephritis is the most common cause of secondary glomerulonephritis and a major cause of rapidly progressive glomerulonephritis. Acute renal failure from specific infection (malaria, leptospirosis, melioidosis), from toxin exposure (snake bite, wasp sting), from exertional heat stroke, and from drugs is frequently found. Nephrolithiasis, distal renal tubular acidosis and hypokalaemia are endemic in NE Thailand. In conclusion, the broad clinical features of renal diseases in South-East Asia are similar to other regions, with additional specific causes from infections, toxic, metabolic and environmental derangements associated with these tropical locations.