CARE Dose 4D combined with sinogram-affirmed iterative reconstruction improved the image quality and reduced the radiation dose in low dose CT of the small intestine

Objective

Multislice computed tomography (MSCT) has been used for diagnosis of small intestinal diseases. However, the radiation dose is a big problem. This study was to investigate whether CARE Dose 4D combined with sinogram‐affirmed iterative reconstruction (SAFIRE) can provide better image quality at a lower dose for imaging small intestinal diseases compared to MSCT.

Methods

The noise reduction ability of SAFIRE was assessed by scanning the plain water mold using SOMATOM Definition Flash double‐source spiral CT. CT images at each stage of radiography for 239 patients were obtained. The patients were divided into groups A and B were based on different tube voltage and current or the image recombination methods. The images were restructured using with filtered back projection (FBP) and SAFIRE (S1–S5). The contrast noise ratio (CNR), CT Dose index (CTDI), subjective scoring, and objective scoring were compared to obtain the best image and reformation parameters at different stages of CT.

Results

Twenty‐six restructuring patterns of tube voltage and current were obtained by FBP and SAFIRE. The average radiation dose using CARE Dose 4D combined with SAFIRE (S4–S5) reduced approximately 74.85% compared to conditions where the tube voltage of 100 kV and tube current of 131 mAs for patients with MSCT small intestinal CT enterography at plain CT scan, arterial stage, small intestine, and portal venous phase. The objective and subjective scoring were all significantly different among groups A and B at each stage.

Conclusions

Combination of CARE Dose 4D and SAFIRE is shown to decrease the radiation dose while maintaining image quality.

Spectrum of malabsorption syndrome among adults & factors differentiating celiac disease & tropical malabsorption

BACKGROUND & OBJECTIVES

Aetiology of malabsorption syndrome (MAS) differs in tropical and temperate countries over time; clinical and laboratory parameters may differentiate between various causes. This study was undertaken to investigate the spectrum of MAS among Indian adults and to find out the features that may help to differentiate between TM and celiac disease.

METHODS

Causes of MAS, and factors differentiating tropical malabsorption (TM) from celiac disease (CD) were determined in 275 patients.

RESULTS

Using standard criteria, causes in 275 patients [age 37.5+13.2 yr, 170, (61.5%) male] were, TM 101 (37%), CD 53 (19%), small intestinal bacterial overgrowth 28 (10%), AIDS 15 (5.4%), giardiasis 13 (5%), hypogammaglobulinemia 12 (4%), intestinal tuberculosis 7 (2.5%), strongyloidiasis 6 (2%), immunoproliferative small intestinal disease 5 (2%), Crohn's disease 6 (2%), amyloidosis 4 (1.5%), intestinal lymphangiectasia 3 (1%) and unknown 22 (8%). On univariate analysis, patients with CD were younger than TM (30.6+12 vs. 39.3+12.6 yr, P<0.001), had lower body weight (41.3+11.8 vs. 49.9+11.2 kg, P<0.001), longer diarrhoea duration (median 36 inter-quartile range 17.8-120 vs. 24-months, 8-48, P<0.01), lower stool frequency (6/day, 5-8 vs. 8, 5-10, P<0.05), lower haemoglobin (9.4+3.2 vs. 10.4+2.7 g/dl, P<0.05), higher platelet count (2,58,000, range 1,35,500-3,23,500 vs. 1,60,000, 1,26,000-2,58,000/mm 3 , P<0.05), and more often had hepatomegaly (9/53, 17% vs. 4/101, 4%, P<0.01), and subtotal or partial villous atrophy (36/50, 72% vs. 28/87, 32%, P<0.001). Younger age (<35 yr), longer diarrhoea duration, higher platelet count and villous atrophy were significant on multivariate analysis.

INTERPRETATION & CONCLUSIONS

TM and CD are common causes of MAS among Indian adults. Younger age (<35 yr), longer diarrhoea duration, higher platelet count and villous atrophy were found to be associated with CD.