Spleen volume calculator (CT/MRI)

Note: while the calculator can be used to estimate organ volume and weight in the adult and pediatric population, the recommendations shown only apply to adult patients.

Notes

Measurements

• L is defined as the cranio-caudal distance between the first and last slices in the axial plane where the spleen is depicted
• D is the largest measureable long axis diameter in the axial plane
• T is the largest perpendicular dimension to D in the axial plane

Splenic index

• The formula:
  • Splenic index = L x D x T
• The normal range of the index is 120-480
  • ^{Strijk SP, Wagener DJ, Bogman MJ, de Pauw BE, Wobbes T. The spleen in Hodgkin disease: diagnostic value of CT. Radiology. 1985 Mar;154(3):753-7. doi: 10.1148/radiology.154.3.3969481. PMID: 3969481.}

Spleen volume

• Organ volume is calculated using the following formula:
  • Spleen volume (cm³) = 30 + 0.58 x L x D x T

• The normal range of the estimated volume in healthy individuals with this formula is: 107.2 – 314.5 cm³ (mean: 214.6 cm³)
  • ^{Prassopoulos P, Daskalogiannaki M, Raissaki M, Hatjidakis A, Gourtsoyiannis N. Determination of normal splenic volume on computed tomography in relation to age, gender and body habitus. Eur Radiol. 1997;7(2):246-8. doi: 10.1007/s003300050145. PMID: 9038125.}
• In a later study using volumetry 236.89±77.58 cm³ was found to be the average normal spleen size, whilst thresholds of 314.47 and 430.84 cm³ were determined for mild and massive splenomegaly respectively
  • ^{Linguraru MG, Sandberg JK, Jones EC, Summers RM. Assessing splenomegaly: automated volumetric analysis of the spleen. Acad Radiol. 2013 Jun;20(6):675-84. doi: 10.1016/j.acra.2013.01.011. Epub 2013 Mar 25. PMID: 23535191; PMCID: PMC3945039}
• In comparison, a study done by Japanese researchers showed much lower values for average spleen volume (112 cm³) and normal range (32-209 cm³)
  • ^{Kaneko J, Sugawara Y, Matsui Y, Ohkubo T, Makuuchi M. Normal splenic volume in adults by computed tomography. Hepatogastroenterology. 2002 Nov-Dec;49(48):1726-7. PMID: 12397778.}

• Body height and gender are also known to influence normal splenic volume, with men and taller individuals on average having larger organ volume
• This chart shows the range of normal spleen volume relative to body height and sex, and can be used to better correlate the estimated splenic volume with the expected normal volume of in different patient cohorts
  • ^{Chow KU, Luxembourg B, Seifried E, Bonig H. Spleen Size Is Significantly Influenced by Body Height and Sex: Establishment of Normal Values for Spleen Size at US with a Cohort of 1200 Healthy Individuals. Radiology. 2016 Apr;279(1):306-13. doi: 10.1148/radiol.2015150887. Epub 2015 Oct 28. PMID: 26509293.}

• Important caveat: the range of reported normal spleen volumes is variable across the literature, and also heavily dependent on patient population, gender, body height, and potentially age
• These should be therefore always factored into the assessment of splenic volume

Spleen weight

• Estimated weight is calculated using the following formula:
  • Spleen weight (grams) = splenic volume x 1.05
  • where 1.05 g/cm³ is the estimated specific gravity of the spleen

• The following normal range values were established in autopsic studies of healthy, adults(!):
  • men: 28-226 g
  • women: <230 g
    • ^{Molina DK, DiMaio VJ. Normal organ weights in men: part II-the brain, lungs, liver, spleen, and kidneys. Am J Forensic Med Pathol. 2012 Dec;33(4):368-72. doi: 10.1097/PAF.0b013e31823d29ad. PMID: 22182984.}
    • ^{Molina DK, DiMaio VJ. Normal Organ Weights in Women: Part II-The Brain, Lungs, Liver, Spleen, and Kidneys. Am J Forensic Med Pathol. 2015 Sep;36(3):182-7. doi: 10.1097/PAF.0000000000000175. PMID: 26108038.}
• It should be noted that that the in vivo and ex vivo weight of the spleen can significantly differ due to changes in blood content, and can be as much as 25-50% higher in vivo
• Therefore, this calculator uses the following imaging-based normal range recommended by Prassopoulos et al.:
  • 112 – 359 g

• Again it has to be emphasized that similarly to splenic volume, organ weight is also dependent on patient demographics

Last updated: 2021-11-21