Imaging Uganda/Africa

Introduction

There are no absolute criteria for the spleen size on ultrasound. When normal, its a little larger than the left kidney. The length should not exceed 15cm in the major axis (from pole to pole). A chronically enlarged spleen may often distort and displace the left kidney, narrowing it in the antero-posterior diameter and width

Clinical presentation

Patients with splenomegaly can present with a variety of symptoms and signs, depending on the underlying cause. The clinical presentation can range from asymptomatic (discovered incidentally) to symptomatic with complications such as Hypersplenism or splenic infarction

Common symptoms

• Left upper quadrant pain or fullness
• Early satiety or abdominal distension. Due to compression of the stomach by the enlarged spleen
• Systemic Symptoms (if due to underlying disease). These include; Fever, Fatigue, recurrent infections and bleeding or bruisng
• Symptoms of complication. Eg Hypersplenism and splenic rapture

Ultrasound features

General Features

• Rounded contour (loss of normal wedge shape)
• Extension below the left costal margin
• Medial displacement of the left kidney
• Compression of adjacent structures (stomach, pancreas)

Doppler Evaluation

• Splenic vein dilation (>10 mm) suggests portal hypertension.
• Increased arterial flow may indicate infection or malignancy.

Homogenous splenomegaly

This may be due to:

1. Tropical splenomegaly, which includes idiopathic splenomegaly, malaria, trypanosomiasis, leishmaniasis and schistosomiasis
2. Sicke cell disease (unless infarcted)
3. Portal hypertension
4. Leukaemia
5. Metabolic disease
6. Lymphoma (may contain hyperechoic masses).
7. Infections such as rubella and mononucleosis

Homogeneous splenomegaly

Note the runded borders of the spleen

Homogeneous splenomegaly

Enlarged spleen compressing the left kidney

Non-homogenous splenomegaly

This is due to focal abnormalities:

1. Splenic cysts; Anechoic, thin-walled, posterior enhancement
   • Congenital cysts
   • Pseudocysts
   • Hydatid cysts
2. Hemangioma; Hyperechoic, well-defined
3. Abscess; Hypoechoic, thick-walled, debris
4. Lymphoma; Hypoechoic, round masses
5. Metastases; Variable (melanoma often hyperechoic)

Splenic cyst

• Well-defined hypoechoic intrasplenic cyst
• Low level homogenous echoes (due to deposition of cholesterol crystals)

Splenic abscess

Hypoechoic, thick-walled cystic splenic mass with debris in a patient with Fever and sepsis

Lymphoma

Multiple hypoechoic, round masses

Splenic metastasis

Hyperechoic splenic masses (arrows) in a patient with breast cancer consistent with splenic metastasis

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