The relationship between splenic length in healthy children from the Eastern Anatolia Region and sex, age, body height and weight

The spleen has an average of 12 cm in length, 7 cm in width and 3–4 cm in thickness in adults. The spleen reaches its maximum size at the age of 13 years. Normally, splenic length (SL) should not exceed 15 cm. The increase in SL is rapid in the first year of life. These limits in children may vary from age to age^(1,2).

The normal limits of spleen size must be known in order for pathological changes to be recognized. It is impractical to calculate the volume of the spleen. For this reason, especially SL determination is more meaningful and important^(1,3–5).

The aim of this study has been to determine the normal range of spleen size in healthy children by ultrasonography, and to reveal its relation to sex, age, body height and weight.

Our retrospective study, approved by the Ethics Committee, designed to standardize the size of the spleen is limited to children in the Eastern Anatolia Region. This study included 310 children (150 girls and 160 boys; age 0–16). The children were divided into 11 different groups: 0–3 months, 3–6 months, 6–12 months, 1–2 years, 2–4 years, 4–6 years, 6–8 years, 8–10 years, 10–12 years, 12–14 years, and 14–16 years. Sex, age, body height, and weight were determined in each case.

Most of the children referred for US examination had various abdominopelvic problems such as nonspecific abdominal pain. Only the children who did not have a spleen pathology on ultrasonography were included in the study. The measured organs had a normal position, contour and echo structure. In the course of about 2 years, each measurement was performed by a radiologist.

For the measurement of SL, each child was placed in a supine and right lateral decubitus position. The measurements were made during deep inspiration wherever possible, with an ultrasound 3.5 MHz convex transducer. The greatest longitudinal distance of the spleen from the dome to the tip (splenic length) measured at the hilum in the coronal plane was obtained (Fig. 1).

Fig. 1

SL was statistically analyzed on a computer using the SPSS/PC version 15.0 package program for sex, body height and weight for each age group. Mean, standard deviation, median, minimum, maximum, 10^th and 90^th percentile values were calculated. The upper and lower limits of 95% confidence interval for mean were determined. The graph of SL average values of the spleen according to age groups was drawn. The „t-test” and the „Nonparametric Mann-Whitney U Test (n < 30)” were used to assess the differences between the two independent groups. Pearson’s correlation coefficients between SL and age, height, and weight were evaluated. Linear regression analysis was performed to determine the exact pattern of the relationship.

The splenic length of three hundred and ten children (150 girls and 160 boys in the age group from 0 to 16 years) was measured by ultrasonography.

There were no significant differences in SL with respect to sex. Also, no statistically significant differences were found between the two sexes in any age group for SL (t-test, p > 0.05). Therefore, all data were rearranged without being separated according to sex.

SL has been presented in a graphic form (Fig. 2). The descriptive analysis of SL (mean, median, minimum and maximum values, standard deviations, 10^th and 90^th percentile values, and lower and upper bounds of a 95% confidence interval) has been shown in Table 1.

Fig. 2

The correlation analysis has shown a positive and significant correlation between SL, age, body height, and weight, with high correlation coefficients (r > 0.80). Among the body parameters, height was the one best correlated with SL. SL relative to body height has been shown in Table 2. Correlation coefficients have been presented in Table 3.

We have built the following prediction models of SL, in millimeters, according to body height and weight as an alternative method for examiners: spleen, 24.934 + (body height [centimeters] x 0.498); 53.757 + (body weight [kilograms] x 1.046).

The results of regression analysis concerning the relationship between SL, body height and weight have been demonstrated in Table 4.

It is important to determine the pathologic changes in spleen sizes in the ultrasonographic evaluation of children^(6–8). The normal ranges should be known, so that pathological changes can be recognized. It should also be noted that the size of the spleen may vary according to the age group of the children. In adulthood, spleen size is bigger in men than in women⁽⁹⁾.

There are numerous studies in the literature related to spleen size in children. However, there has been no such retrospective study investigating splenic size in children from the Eastern Anatolia Region. Our aim was to determine the normal standards of spleen sizes in Turkish children living in the Eastern Anatolia Region.

Ultrasonography is the most widely used imaging method in routine practice that does not expose patients to ionizing radiation. Ultrasonographic examination can be performed in a supine and mild right lateral decubitus position. In our study, the greatest longitudinal distance of the spleen from the dome to the tip (splenic length), measured at the hilum in the coronal plane was obtained.

There is significant growth in the first 3–4 years of life in the spleen. The maximum size is reached at 13 years old^(1,2,9). Spleen size is different for each pediatric age group until they are adult⁽¹⁰⁾. We observed that the increase in SL is much more rapid during the first years of life.

It is impractical to calculate the volume of the spleen. It is also useless to associate it with body surface area, which is a somatometric parameter in daily practice. For that reason, SL is significant^(1,2,9–11).

We accepted the sizes between the 10^th and the 90^th percentile as within normal limits. In most other studies, the 5^th and the 95^th percentile were the accepted normal limits. We have shown the normal values, lower and upper bounds of a 95% confidence interval in Table 1.

There are no significant differences between the sexes in children. Sex certainly is not a determining factor for organ dimensions in the pediatric age group^(3,10,12,13). We did not find any significant difference in spleen sizes between the two sexes of any age group (t-test, p > 0.05). Therefore, all data were rearranged without being separated according to sex.

It has been found that SL correlates better with height in most studies^{(1,10,12,14–18)}. The results of our study are in accordance with the findings of those studies. On the other hand, in some studies weight or age correlate better with splenic length^{(3,13,19–22)}.

Our results provide a standard set of normal ranges of spleen size according to the age of the children, as determined by ultrasonography. We present our data both in tabular and graphic forms with the aim of enabling a more practical evaluation during a sonographic examination. The tables are practical for routine use in US examinations.

The normal limits of spleen size are important parameters during a sonographic examination. This study has revealed SL to show the best correlation with body height. Sex is not a determining factor for spleen size in the pediatric age group. We hope our research can be used as a background for further study of a larger population, and contributes to daily practice in radiology clinics.