Effect of food intake on liver and spleen volume: assessment with single photon emission computed tomography

Methods of Ultrasound Spleen Morphometry

This article presents a review of the methods of determining spleen size in sonography, computed tomography, and magnetic resonance imaging. The review aims to summarize the data on the methods of estimating the linear dimensions of the spleen and splenic volume and describe the physiological variability of spleen size depending on sex, age, and different physiological conditions. We systematized the methods used for measuring the spleen and presented them in the form of a table, analyzed the results of previous studies, and compared the accuracy of different methods of calculating the splenic volume using a variety of diagnostic methods.

Postprandial dynamics of splenic volume in healthy volunteers

Throughout the history of medicine, many functions have been attributed to the spleen and numerous researchers have focused on a postulated digestive function. Beginning in 1825, systematic animal studies showed evidence for a postprandial increase in splenic volume (SV) with a peak 30 min to five hours after food intake. Since the introduction of imaging techniques, two studies have been conducted on humans, revealing a decrease in SV 30 to 45 min postprandially. The aim of this study was to examine possible postprandial changes in SV over a period of seven hours. The ethics-approved, randomized crossover study included 10 healthy volunteers, who received a standardized meal (3,600 kJ) on one study day and fasted on the other. Sonographic measurements were obtained at six measurement points on each day. Thirty minutes after the meal, SV increased significantly by 38.2 ± 51.2 cm3 (17.3%; p = .04) compared to the baseline measurement and decreased gradually afterward. In males, SV 30 min after the meal was 70.2 ± 21.6 cm3 higher (p = .002) compared to the fasting condition and 60 min later it was still significantly increased. The apparent SV increase after food intake is discussed in relation to hemodynamic changes in the splanchnic region. It seems plausible that the spleen has a rhythmic and regulative function within the portal system, something which warrants further research and should be taken more into account in nutritional physiology.

Effect of Breath Holding on Spleen Volume Measured by Magnetic Resonance Imaging

Objective

Ultrasonographic studies have demonstrated transient reduction in spleen volume in relation to apnea diving. We measured spleen volume under various respiratory conditions by MR imaging to accurately determine the influence of ordinary breath holding on spleen volumetry.

Materials and Methods

Twelve healthy adult volunteers were examined. Contiguous MR images of the spleen were acquired during free breathing and during respiratory manipulations, including breath holding at the end of normal expiration, breath holding at deep inspiration, and the valsalva maneuver, and spleen volume was measured from each image set based on the sum-of-areas method. Acquisition during free breathing was performed with respiratory triggering. The duration of each respiratory manipulation was 30 s, and five sets of MR images were acquired serially during each manipulation.

Results

Baseline spleen volume before respiratory manipulation was 173.0 ± 79.7 mL, and the coefficient of variance for two baseline measures was 1.4% ± 1.6%, suggesting excellent repeatability. Spleen volume decreased significantly just after the commencement of respiratory manipulation, remained constant during the manipulation, and returned to the control value 2 min after the cessation of the manipulation, irrespective of manipulation type. The percentages of volume reduction were 10.2% ± 2.9%, 10.2% ± 3.5%, and 13.3% ± 5.7% during expiration breath holding, deep-inspiration breath holding, and the valsalva maneuver, respectively, and these values did not differ significantly.

Conclusions

Spleen volume is reduced during short breath-hold apnea in healthy adults. Physiological responses of the spleen to respiratory manipulations should be considered in the measurement and interpretation of spleen volume.

Variability of preoperatively determined hepatic volumes in potential living liver donors

RATIONALE AND OBJECTIVES

The aim of the study is to evaluate variability in hepatic volumes during the preoperative period in potential liver donors.

MATERIALS AND METHODS

Eight potential living liver donors underwent preoperative multirow-detector computed tomographic assessment of hepatic transplant volumes twice. Intraindividual delay between the two examinations range was 3-62 days (mean, 30.1 days). Liver volumes were determined in a blinded fashion by an experienced radiologist and a transplantation surgeon. Results were compared and correlated with time of data acquisition during the day.

RESULTS

Interobserver variability for assessments of liver volumes range was 6-32 mL (mean, 16 mL). Intraindividually, the difference between the two volume assessments ranged between -103 and +45 mL (mean, -19 mL), corresponding to percentages of alteration between -7.5% and +3.2%. There was no statistical correlation evident concerning volume alterations and specific time of data acquisition.

CONCLUSION

Neither time of data acquisition nor waiting period for the surgical procedure seems to affect the accuracy of liver volume calculation. Apparent volume variations likely are in the range of the method error of the applied technique.

Postprandial decrease in splenic volume demonstrated by magnetic resonance imaging and stereology

The aim of this study was to determine if the volume of the spleen changes after food intake. We applied an unbiased and efficient method for splenic volume estimation using magnetic resonance imaging (MRI) in combination with modern design stereology. MR images of the spleen were obtained for 10 healthy volunteers (five men and five women; mean age 28.9 years [range 23-35 years]) without a history of splenomegaly. The initial scans were performed in the morning after overnight fasting. Each volunteer then consumed a standard balanced meal weighing 500 g [2,460 kJ (627 kcal) energy] with 500 ml of still mineral water. Second identical MR scans were performed approximately 1 hr later. Postprandially, splenic volume decreased by an average of 6.6% (P = 0.005), probably due to increased splanchnic blood flow after food intake.