Down syndrome and aberrant right subclavian artery

Down syndrome (DS) may be associated with various organ system disorders. Feeding problems are frequent in children with DS and may be caused by associated defects, including congenital heart defects, gastrointestinal defects, or endocrine disorders. In the absence of these associated conditions, feeding problems are often attributed to general hypotonia. However, an aberrant right subclavian artery (ARSA), a rare vascular anomaly and an unusual cause of problems with the passage of solid food through the esophagus, has recently been suggested to occur more frequently in patients with DS. This knowledge is of importance when evaluating feeding difficulties in patients with DS. Additional investigation for identifying an ARSA may be indicated in selected patients. Diagnostic techniques, such as transthoracic echocardiography, barium contrast esophagram, angiography, or computed tomography–angiography (CT) can be used in a diagnostic flow chart. The presence of ARSA is not synonymous to the cause of feeding problems in patients with DS and corrective surgery of this vascular anomaly should be restricted to selected cases

Gastric Emphysema: An Etiologic Classification

I Gas within the wall of the stomach is a rare radiologic finding. The stomach has been the least often reported site of intramural gas in the hollow viscera. Based on etiology, gas in the wall of the stomach can be classified as either gastric emphysema or emphysematous gastritis. Gastric emphysema may be classified into traumatic, pulmonary or obstructive types depending upon the mechanism and pathogenesis. Three cases of gastric emphysema, each of different etiology, are presented to emphasize the subclassification of gastric emphysema. The clinical and prognostic significance of this classification is emphasized.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72543/1/j.1440-1673.1984.tb02363.x.pd

Noninvasive estimation of tumour viability in a xenograft model of human neuroblastoma with proton magnetic resonance spectroscopy (1H MRS)

The aim of the study was to evaluate proton magnetic resonance spectroscopy (1H MRS) for noninvasive biological characterisation of neuroblastoma xenografts in vivo. For designing the experiments, human neuroblastoma xenografts growing subcutaneously in nude rats were analysed in vivo with 1H MRS and magnetic resonance imaging at 4.7 T. The effects of spontaneous tumour growth and antiangiogenesis treatment, respectively, on spectral characteristics were evaluated. The spectroscopic findings were compared to tumour morphology, proliferation and viable tumour tissue fraction. The results showed that signals from choline (Cho)-containing compounds and mobile lipids (MLs) dominated the spectra. The individual ML/Cho ratios for both treated and untreated tumours were positively correlated with tumour volume (P<0.05). There was an inverse correlation between the ML/Cho ratio and the viable tumour fraction (r=−0.86, P<0.001). Higher ML/Cho ratios concomitant with pronounced histological changes were seen in spectra from tumours treated with the antiangiogenic drug TNP-470, compared to untreated control tumours (P<0.05). In conclusion, the ML/Cho ratio obtained in vivo by 1H MRS enabled accurate assessment of the viable tumour fraction in a human neuroblastoma xenograft model. 1H MRS also revealed early metabolic effects of antiangiogenesis treatment. 1H MRS could prove useful as a tool to monitor experimental therapy in preclinical models of neuroblastoma, and possibly also in children