What is the next best step in managing a patient with a history of endometriosis, increased abdominal pain, and complex ovarian cysts on CT?

Management of Complex Ovarian Cysts in a Patient with Endometriosis

The next best step for this patient with endometriosis, increased abdominal pain, and complex ovarian cysts is to obtain a pelvic ultrasound (transvaginal and transabdominal) to further characterize the cysts and determine appropriate management. 1

Rationale for Pelvic Ultrasound

Ultrasound is the preferred initial imaging modality for further evaluation of ovarian cysts for several important reasons:

• It allows for detailed characterization using the O-RADS (Ovarian-Adnexal Reporting and Data System) risk stratification system to determine malignancy risk
• It can better differentiate between endometriomas and infected/complicated cysts
• It provides real-time assessment without radiation exposure
• It can evaluate for signs of torsion or rupture that may require urgent intervention

Analysis of CT Findings

The CT findings show:

• Two complex right ovarian cysts (2.6 cm and 2 cm)
• Mild peripheral enhancement
• Mild adjacent edema

While CT is useful for initial detection, it has limitations in characterizing adnexal masses. The peripheral enhancement and edema raise concern for potential infection of existing endometriomas, which requires further evaluation.

Risk Stratification Using O-RADS

Based on the O-RADS US risk stratification system 1:

1. Typical endometriomas <10 cm are classified as O-RADS 2 (almost certainly benign, <1% risk of malignancy)
2. However, if there are concerning features (enhancement, edema suggesting infection), further evaluation is needed
3. The presence of pain with these imaging findings warrants additional characterization

Management Algorithm

1. Immediate step: Pelvic ultrasound (transvaginal and transabdominal)

   • Evaluate for classic endometrioma features (ground glass/homogeneous low-level echoes)
   • Assess for signs of infection (increased vascularity, complex internal echoes)
   • Look for signs of torsion (absent blood flow)

2. If ultrasound confirms infected endometriomas:

   • Gynecology consultation
   • Antibiotic therapy
   • Possible surgical intervention

3. If ultrasound shows typical endometriomas without infection:

   • Pain management
   • Follow-up imaging in 8-12 weeks

4. If ultrasound shows higher O-RADS classification (3 or above):

   • Gynecologic oncology referral may be warranted

Important Considerations

• While endometriomas are typically benign, superimposed infection can occur and requires prompt treatment 1
• CT has limitations in characterizing adnexal masses compared to ultrasound or MRI 1
• The patient's history of endometriosis increases the likelihood these are endometriomas, but does not exclude other pathologies
• The presence of pain with complex cysts warrants thorough evaluation to rule out complications

Common Pitfalls to Avoid

1. Assuming all cysts in patients with endometriosis are endometriomas - Other pathologies can coexist
2. Delaying evaluation of potentially infected cysts - This can lead to abscess formation or sepsis
3. Overreliance on CT findings alone - Ultrasound provides better characterization of adnexal masses
4. Failure to consider surgical intervention - Large (>4 cm) or symptomatic endometriomas may benefit from surgical management 2

Ultrasound will provide the most definitive next step in characterizing these cysts and guiding appropriate management, whether conservative or surgical, based on a more complete assessment of the cysts' nature and potential complications.