What is a normal spleen size in adults?

Normal Spleen Size in Adults

The normal spleen size in adults is defined as a vertical length of 13 cm or less when measured in the coronal plane. 1

Standardized Measurement Technique

• Spleen size should be measured in the coronal plane as a vertical length 1
• Measurement can be performed using:
  • CT scan: measuring the vertical length in the coronal image 1
  • Ultrasound: measuring the greatest longitudinal diameter from dome to tip at the hilum in the coronal plane 2, 3
  • Alternative calculation: multiplying the number of spleen slices in transverse CT views by the thickness of each slice 1
  • PET/CT: measuring splenic coronal diameter on a PET maximum intensity projection image 1

Normal Size Parameters

• Length: ≤13 cm is considered normal 1
• Width: Normal values typically range from 7-8 cm 3, 4
• Thickness: Normal values typically range from 4-5 cm 3, 4
• Volume: Average normal volume ranges from 150-200 cm³ 2, 3

Variations in Normal Spleen Size

• Gender differences: Males tend to have larger spleens than females 2, 3

  • Male average length: 10.6-11.1 cm 2, 3
  • Female average length: 10.1-10.7 cm 2, 3

• Correlation with body parameters:

  • Spleen size correlates most strongly with height and weight 2
  • Weaker correlations exist with BMI and age 2
  • Spleen volume tends to decrease with age (negative correlation) 5

Clinical Significance

• A spleen measuring 11-13 cm in length is considered mild splenomegaly 6
• Splenomegaly >13 cm is considered clinically significant 1, 6
• In lymphoma staging and assessment, splenomegaly is defined as >13 cm in vertical length 1

Important Considerations

• Normal spleen size can vary based on race, body size, and height 1
• A spleen may be normal in size but still contain pathology (e.g., lymphoma) 1
• Enlargement may be due to non-pathological causes such as variations in blood volume or use of hematopoietic growth factors 1
• When evaluating spleen size in clinical practice, imaging is more reliable than physical examination 7

Pitfalls in Spleen Size Assessment

• Physical examination alone is unreliable for detecting mild to moderate splenomegaly 7
• A normal-sized spleen does not rule out splenic pathology 1
• Various medical conditions can affect spleen size without indicating primary splenic disease 1
• Different imaging modalities may yield slightly different measurements 2, 3