Korean J Radiol.  2003 Dec;4(4):234-238. 10.3348/kjr.2003.4.4.234.

Correlation of Patient Weight and Cross-Sectional Dimensions with Subjective Image Quality at Standard Dose Abdominal CT

• Kalra MK
• Maher MM
• Prasad SR
• Hayat MS
• Blake MA
• Varghese J
• Halpern EF
• Saini S

• KMID: 1111252
• DOI: http://doi.org/10.3348/kjr.2003.4.4.234

Abstract

OBJECTIVE
We evaluated the association between patients' weight and abdominal cross-sectional dimensions and CT image quality. MATERIALS AND METHODS: We prospectively evaluated 39 cancer patients aged more than 65 years with multislice CT scan of abdomen. All patients underwent equilibrium phase contrast-enhanced abdominal CT with 4 slices (from top of the right kidney) obtained at standard tube current (240 280 mA). All other scanning parameters were held constant. Patients' weight was measured just prior to the study. Cross-sectional abdominal dimensions such as circumference, area, average anterior abdominal wall fat thickness and, anteroposterior and transverse diameters were measured in all patients. Two subspecialty radiologists reviewed randomized images for overall image quality of abdominal structures using 5-point scale. Non-parametric correlation analysis was performed to determine the association of image quality with patients' weight and cross-sectional abdominal dimensions. RESULTS: A statistically significant negative linear correlation of 0.46, 0.47, 0.47, 0.58, 0.56, 0.54, and 0.56 between patient weight, anterior abdominal fat thickness, anteroposterior and transverse diameter, circumference, cross-sectional area and image quality at standard scanning parameters was found (p< 0.01). CONCLUSION: There is a significant association between image quality, patients' weight and cross-sectional abdominal dimensions. Maximum transverse diameter of the abdomen has the strongest association with subjective image quality.

Keyword

Computed tomography (CT)

MeSH Terms

Aged
Aged, 80 and over
Body Weight/*physiology
Body Weights and Measures/*statistics & numerical data
Contrast Media/administration & dosage
Female
Human
Male
Observer Variation
Prospective Studies
Radiation Dosage
Radiography, Abdominal/*methods
Statistics, Nonparametric
Tomography, X-Ray Computed/*methods

Figure

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  Fig. 1 Scatter graph depicting distribution of patients' weight.

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  Fig. 2 Scatter graph depicting distribution of patients' transverse diameter.

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