Is a hemorrhagic cyst the same as a simple cyst?

Hemorrhagic Cyst vs Simple Cyst: Key Differences

No, a hemorrhagic cyst is not the same as a simple cyst—they are distinct entities with different imaging characteristics, clinical implications, and management approaches. 1

Defining Characteristics

Simple Cysts

• Simple cysts are anechoic (completely fluid-filled), well-circumscribed, round or oval structures with imperceptible walls and posterior acoustic enhancement on ultrasound 1
• They contain clear fluid without internal debris, septations, or solid components 1
• Simple cysts in premenopausal women are typically functional and carry no increased risk of malignancy, regardless of size 1
• In premenopausal women, simple cysts <5 cm require no follow-up 1

Hemorrhagic Cysts

• Hemorrhagic cysts are classified as "complicated" non-simple cysts that contain blood products but lack solid components 1
• They display characteristic ultrasound findings including a reticular pattern (fine intersecting lines representing fibrin strands), retracting clot with angular margins, and peripheral vascularity without internal blood flow 2
• On MRI, hemorrhagic cysts show heterogeneous hyperintensity on both T1- and T2-weighted sequences, which distinguishes them from simple cysts 1
• The malignancy risk for hemorrhagic cysts is very low (<2%), similar to simple cysts 1

Clinical Significance

Pathophysiology

• Hemorrhagic cysts result from bleeding into a pre-existing functional cyst, typically from injury to fragile blood vessels in the cyst wall 1
• They occur most commonly in the second half of the menstrual cycle and are almost always benign luteal cysts 3
• Risk increases with larger cyst size (>8 cm) and anticoagulation therapy 1, 4

Symptom Presentation

• Simple cysts are typically asymptomatic 1
• Hemorrhagic cysts can cause sudden, severe pelvic pain (in 80% of cases) without hemodynamic instability 1
• Pain from hemorrhagic cysts typically resolves within days to weeks with conservative management 1

Management Differences

Simple Cysts

• Premenopausal women with simple cysts <5 cm: no follow-up needed 1
• Simple cysts >5 cm but <10 cm: follow-up ultrasound only if clinically indicated 1

Hemorrhagic Cysts

• For typical hemorrhagic cysts ≤5 cm in premenopausal women: no further management required 2
• For hemorrhagic cysts >5 cm but <10 cm: follow-up ultrasound in 8-12 weeks is recommended 2
• If the cyst persists or enlarges during follow-up, refer to gynecologist or obtain MRI 2
• Conservative management is preferred; avoid aspiration or surgical intervention during active hemorrhage 1, 2

Anticoagulation Considerations

• For patients on anticoagulation with hemorrhagic cyst bleeding, interrupt aspirin for 3 days following hemorrhage onset 2
• Consider restarting anticoagulants between 7-15 days after hemorrhage onset, balancing thromboembolism risk 1, 2
• For dual antiplatelet therapy, continue P2Y12 inhibitor while interrupting aspirin 2

Critical Pitfalls to Avoid

• Do not assume hemorrhagic cysts and simple cysts are interchangeable—they have different imaging appearances and may require different follow-up 1
• Never perform fine-needle aspiration of ovarian cysts, whether simple or hemorrhagic 2
• Avoid invasive procedures during active hemorrhage from a hemorrhagic cyst 1, 2
• In postmenopausal women, hemorrhagic cysts should not typically occur; when found, further evaluation is required 2
• Hemorrhagic cysts will decrease or resolve on follow-up imaging in 8-12 weeks, unlike persistent non-functional cysts 1