NUMBERS & MEASUREMENTS

Quick reference for diagnostic thresholds, normal values, and measurement criteria

Spleen

Adults - Ultrasound

Women: 12-13 cm upper limit[1]
Men: 13-14 cm upper limit[1]
Height-adjusted algorithms available[1]
26% of men exceed 12 cm cutoff[1]

Children - Ultrasound

Increases nonlinearly with age/height[2,3]
Minimal sex differences[2]
Use 95th percentile for age[2]

Children - CT

Volume: 28-480 mL (0-18 years)[4]
Predictors: Weight (β=2.4), Age (β=0.3)[4]
>12 cm: Splenomegaly threshold[5]

Liver

Adults - MRI Volume

Mean: 1505 ± 385 cm³[6]
Healthy: 1360 ± 273 cm³[6]
Influenced by age, sex, BMI[6]

Adults - CT

Mean volume: 1533 ± 375 mL[7]
Hepatomegaly: >14.0×weight(kg)+979 mL[7]
Craniocaudal: <19 cm[7]
Max 3D: <24 cm[7]

Adults - MRI Diameters

Craniocaudal: 17.2 ± 2.0 cm[8]
Anterior-posterior: 15.8 ± 1.9 cm[8]
Medial-lateral: 19.7 ± 2.3 cm[8]

Children - Ultrasound

1-2 cm larger in Central Europeans[9]
Larger in boys (significant)[9]
Use ethnically appropriate charts[9]

Children - CT

Volume: 340-2,002 mL (0-18 years)[4]
Weight (β=12.5), Age (β=1.7)[4]
Female (β=-35.3)[4]

Prostate

Adults - MRI Zones

Whole prostate: Increases with age[10]
Central gland: Increases with age[10]
Peripheral zone: No age correlation[10]
Growth rate: 2.5%/year median[13]

Adults - TRUS by Age

40-49 years: ~25 mL[12]
50-59 years: ~30 mL[12]
60-70 years: ~35 mL[12]
TZ grows faster than total volume[12]

Children/Young Adults - MRI

2-5 years: 0.00 cm³[15]
6-10 years: 0.05 cm³[15]
11-15 years: 2.83 cm³[15]
16-20 years: 8.32 cm³[15]
21-25 years: 11.56 cm³[15]

Uterus

Premenopausal - Ultrasound

Peak length: 72 mm at age 40[16]
Length/width ratio: 1.618 (golden)[16]
Nulliparous < Parous[17]
Peak volume: 41-50 years[18]

Postmenopausal - Ultrasound

Volume: -20% at 1 year[19]
Volume: -35% at 2 years[19]
Corpus-cervix ratio decreases[17]

Children/Adolescents

Mean: 25.5 ± 27.0 cm³ (0-20 years)[20]
84% variation due to age[21]
Progressive rise through adolescence[21]

Ovary

Premenopausal - Ultrasound

Mean: 4.9 ± 0.03 cm³[22]
Upper limit: 20 cm³[22,23]
Peak: 7.7 mL at age 20[24]
<30 years: 6.6 cm³[22]
40-49 years: 4.8 cm³[22]

Postmenopausal - Ultrasound

Mean: 2.2 ± 0.01 cm³[22]
Upper limit: 10 cm³[22,23]
At menopause: ~2.8 mL[24]
Left: -45% at 2 years post[25]
Right: -20% at 2 years post[25]

Children - Ultrasound

Age 2: 0.7 mL (0.4-1.1)[24]
Pre-pubertal: 1.67 mL (1.02-2.32)[26]
Menopause cutoff: <4 cm³ + age ≥48[27]

Endometrium

Premenopausal - Ultrasound

Day 4: ≤4 mm[17]
Day 8: ≤8 mm[17]
Follicular: Increases significantly[28]
Luteal: Plateau maintained[28]
Mean: 4.5 ± 3.7 mm (0-20 years)[20]

Postmenopausal - Ultrasound

Upper limit: 5 mm[17]
Mean: 3.6 mm[17]
-9% at 1 year post[19]
-18% at 2 years post[19]

MRI - Reproductive Age

Thinnest: Menstrual phase[29]
Thickest: Late secretory phase[29]
Peak: 41-50 years[18]

MSK (Musculoskeletal)

Femoroacetabular Impingement (FAI)

Center Edge Angle:

<20°: Acetabular dysplasia
20-25°: Borderline acetabular dysplasia
25-40°: Normal
>40°: Pincer type morphology

Vascular

Aorta

Ascending Aorta:

4.0-4.4 cm: Dilated
>4.5 cm: Aneurysm

Ascending Aorta — Size for Intervention:

≥4.5 cm: Loeys-Dietz, ACTA2 (4.2 cm if high risk)
≥5.0 cm: BAV / Marfan at aortic center of excellence
≥5.5 cm: BAV / Marfan

Infrarenal Aorta:

>3 cm (outer wall to outer wall): Aneurysm

Main Pulmonary Artery

<2.9 cm: Normal

Gastrointestinal

Organ Size Thresholds

Hepatomegaly: >18 cm craniocaudal
Splenomegaly: >13 cm craniocaudal

Genitourinary

Uterine Measurements

Thickened junctional zone: >12 mm

Cardiac

Aortic Stenosis Severity

Mild: <2 cm²
Severe: <1 cm²
Critical: <0.8 cm²

Ultrasound

Doppler & Flow

Portal Vein Flow: <15 cm/s

Endometrium

<5 mm: Likely atrophy
4-5 mm: Requires biopsy

Bladder

Postvoid Volume: <100 mL

Amniotic Fluid

Amniotic Fluid Index (AFI):

<5 cm: Oligohydramnios
>25 cm: Polyhydramnios

Deepest Vertical Pocket:

<2 cm: Oligohydramnios
>8 cm: Polyhydramnios

Pediatrics

Catheter Positioning

Umbilical Artery Catheter: T5-T9

Pyloric Stenosis

Pyloric wall thickness: >3 mm
Pyloric channel length: >15 mm

Other Pediatric Measurements

Intussusception diameter: >2.5 cm
ECMO catheter tip: Right atrium

References

[1]Chow KU, et al. Spleen Size Is Significantly Influenced by Body Height and Sex. Radiology. 2016.
[2]Pelizzo G, et al. Spleen Size Evaluation in Children. PloS One. 2018.
[3]Nemati M, et al. Normal Values of Spleen Length and Volume: An Ultrasonographic Study in Children. Ultrasound Med Biol. 2016.
[4]de Padua V Alves V, et al. CT-Based Measurements of Normative Liver and Spleen Volumes in Children. Pediatr Radiol. 2023.
[5]Polverelli N, et al. Splenomegaly in Patients With Primary or Secondary Myelofibrosis. Lancet Haematol. 2022.
[6]Kromrey ML, et al. Reference Values of Liver Volume in Caucasian Population. Eur J Radiol. 2018.
[7]Perez AA, et al. Deep Learning CT-based Quantitative Visualization Tool for Liver Volume Estimation. Radiology. 2022.
[8]Seppelt D, et al. Simple Diameter Measurement as Predictor of Liver Volume. Sci Rep. 2022.
[9]Waelti S, et al. Normal Sonographic Liver and Spleen Dimensions in Central European Pediatric Population. BMC Pediatr. 2021.
[10]Turkbey B, et al. Age-Related Changes in Prostate Zonal Volumes. BJU Int. 2012.
[11]Laschkar S, et al. Zonal Anatomy of the Prostate Using MRI. Br J Radiol. 2022.
[12]Zhang SJ, et al. Relationship Between Age and Prostate Size. Asian J Androl. 2012.
[13]Loeb S, et al. Prostate Volume Changes Over Time. J Urol. 2009.
[14]Sharkey C, et al. Zonal Growth Pattern of the Prostate. J Urol. 2022.
[15]Ren J, et al. MRI to Predict Prostate Growth in Children. Eur Radiol. 2015.
[16]Verguts J, et al. Normative Data for Uterine Size According to Age. Ultrasound Obstet Gynecol. 2013.
[17]Merz E, et al. Sonographic Size of Uterus and Ovaries. Ultrasound Obstet Gynecol. 1995.
[18]Hauth EA, et al. MR Imaging of Uterus and Cervix in Healthy Women. Eur Radiol. 2007.
[19]Li J, et al. Changes in Uterine Morphology During Ovarian Aging. Menopause. 2020.
[20]Gilligan LA, et al. Normative Values for Female Pelvic Organs. Pediatr Radiol. 2019.
[21]Kelsey TW, et al. Validated Normative Model for Human Uterine Volume. PloS One. 2016.
[22]Pavlik EJ, et al. Ovarian Volume Related to Age. Gynecol Oncol. 2000.
[23]Clarke-Pearson DL. Screening for Ovarian Cancer. N Engl J Med. 2009.
[24]Kelsey TW, et al. Ovarian Volume Throughout Life. PloS One. 2013.
[25]Sokalska A, Valentin L. Changes in Uterus and Ovaries During Menopausal Transition. Ultrasound Obstet Gynecol. 2008.
[26]Moro F, et al. Physiological Sonographic Features of Ovary. J Endocrinol Invest. 2023.
[27]Giacobbe M, et al. Ovarian Volume, Age, and Menopausal Status. Menopause. 2004.
[28]Raine-Fenning NJ, et al. Defining Endometrial Growth During Menstrual Cycle. BJOG. 2004.
[29]Liubing C, et al. MRI Thicknesses of Endometrium and Junction Zone. Acta Radiol. 2023.
[30]Putukian M, et al. Mononucleosis and Athletic Participation. Clin J Sport Med. 2023.