Adrenal and nephrogenic hypertension: an image quality study of low tube voltage, low-concentration contrast media combined with adaptive statistical iterative reconstruction

Int J Clin Pract. 2016 Sep:70 Suppl 9B:B29-36. doi: 10.1111/ijcp.12860.

Abstract

Purpose: The aim of this study was to investigate the effect of using low tube voltage, low-concentration contrast media and adaptive statistical iterative reconstruction (ASIR) for reducing the radiation and iodine contrast doses in adrenal and nephrogenic hypertension patients.

Methods and materials: A total of 148 hypertension patients who were suspected for adrenal lesions or renal artery stenoses were assigned to two groups and. Group A (n=74) underwent a low tube voltage, low molecular weight dextran enhanced multi-detector row spiral CT (MDCT) (80 kVp, 270 mg I/mL contrast agent), and the raw data were reconstructed with standard filtered back projection (FBP) and ASIR at four different levels of blending (20%, 40%, 60% and 80%, respectively). The control group (Group B, n=74) underwent conventional MDCT (120 kVp, 370 mg I/mL contrast agent), and the data were reconstructed with FBP. The CT values, standard deviation (SD), signal-noise-ratio (SNR) and contrast-noise-ratio (CNR) were measured in the renal vessels, normal adrenal tissue, adrenal neoplasms and subcutaneous fat. The volume CT dose index (CTDIvol ) and dose length product (DLP) were recorded, and an effective dose (ED) was obtained. Two-tailed independent t-tests, paired Chi-square tests and Kappa consistency tests were used for statistical analysis of the data.

Results: The CTDIvol , DLP and total iodine dose in group A were decreased by 47.8%, 49.0% and 26.07%, respectively, compared to group B (P<.001). In the qualitative quality analysis, the radiologists rated the 60% ASIR the highest. The mean value of noise (SD) was significantly lower in the 40%, 60% and 80% ASIR-A groups compared with FBP-B for all comparisons. Compared to FBP-B, CNR was significantly higher, with 40%, 60% and 80% ASIR in renal artery stems (P<.05). Compared with FBP-B, a significant increase in the SNR of 40%, 60%, or 80% ASIR was observed in all cases (P<.05).

Conclusions: Compared with conventional protocols, the use of low tube voltage, low-concentration contrast media and 60% ASIR provides similar enhancement and image quality with a reduced radiation dose and contrast iodine dose.

Publication types

  • Clinical Trial

MeSH terms

  • Adolescent
  • Adrenal Gland Diseases / complications
  • Adrenal Gland Diseases / diagnostic imaging*
  • Adult
  • Aged
  • Contrast Media / administration & dosage*
  • Female
  • Humans
  • Hypertension / diagnostic imaging*
  • Hypertension / etiology
  • Hypertension, Renovascular / diagnostic imaging*
  • Hypertension, Renovascular / etiology
  • Male
  • Middle Aged
  • Radiation Dosage
  • Renal Artery Obstruction / complications
  • Renal Artery Obstruction / diagnostic imaging
  • Signal-To-Noise Ratio
  • Tomography, Spiral Computed / methods
  • Tomography, X-Ray Computed / methods*
  • Young Adult

Substances

  • Contrast Media