What Is a Septated Cyst? Causes and What to Expect

A cyst is a sac that can form in various parts of the body, typically filled with fluid, air, or other material. Some cysts feature internal divisions or walls, known as septations, which create multiple compartments within the sac. This structural difference distinguishes them from simple cysts, which are usually smooth-walled and lack internal partitions.

Characteristics of Septated Cysts

Septations are internal walls or partitions that divide a cyst into multiple sections. These internal divisions can vary in appearance; some are thin and smooth, while others may be thicker or irregular. Unlike simple cysts, which typically appear as a single, smooth-walled space on imaging, septated cysts show internal lines or walls that segment the cyst.

The formation of septations within a cyst can arise from several factors. One reason is an inflammatory process, where the body’s response to irritation or injury leads to the development of internal scarring or adhesions that form these walls. Hemorrhage, or bleeding into a cyst, can also result in temporary septations as blood clots organize and create internal divisions. Certain growth patterns of cells within the cyst or the surrounding tissue can also contribute to these internal partitions.

Septations are common in certain types of cysts, such as benign cystadenomas, and can also be found in conditions like hemorrhagic cysts. Their appearance on imaging can provide clues about the cyst’s nature. For instance, hemorrhagic cysts may display thin, mobile septations on ultrasound, representing organized blood clots.

Identification of Septated Cysts

Many septated cysts are discovered incidentally during medical imaging performed for unrelated conditions, as they often do not cause any noticeable symptoms. However, if a septated cyst grows to a significant size or begins to exert pressure on nearby organs, it can lead to symptoms. These symptoms can include pain or a feeling of pressure in the affected area, which may vary in intensity depending on the cyst’s location and size.

Medical professionals use several imaging modalities to detect and characterize septated cysts. Ultrasound is frequently the initial imaging technique employed due to its ability to visualize fluid-filled structures and internal septations. On an ultrasound, septations appear as linear structures crossing the cystic space, and their thickness can be assessed. Ultrasound can also help determine if there is blood flow within the septations, which can be a relevant feature.

Computed Tomography (CT) scans offer cross-sectional views, providing additional information about the cyst’s structure and its relationship to surrounding tissues. While CT is effective for detecting calcifications and overall wall structures, it may be less sensitive than ultrasound for visualizing thin septations. Magnetic Resonance Imaging (MRI) provides detailed soft tissue contrast, making it particularly useful for characterizing complex cystic structures and their contents. MRI can reveal varying signal intensities within different compartments of a septated cyst, helping to distinguish between different types of fluid or other materials present.

Clinical Considerations and Management

The presence of septations often prompts closer evaluation compared to simple cysts. While most septated cysts are benign, certain features can indicate a need for further assessment. Medical professionals consider factors like septa thickness, presence of solid components, and vascularity (blood flow) within the septations or solid areas. Patient symptoms and the cyst’s growth pattern are also taken into account.

For septated cysts that appear benign and are not causing symptoms, watchful waiting with regular imaging follow-ups is a common management approach. This monitoring typically involves serial ultrasound examinations over several months to observe any changes in the cyst’s size or characteristics. For instance, asymptomatic premenopausal women with septated ovarian cysts smaller than 5 cm are often managed with follow-up ultrasound in 8-12 weeks. Many septated cysts, especially ovarian ones, can resolve on their own over time.

Intervention may be considered if the cyst causes persistent symptoms, shows rapid growth, or exhibits suspicious features on imaging that suggest a higher risk profile. Such suspicious features can include thick septations (e.g., greater than 3 mm), irregular walls, solid components, or increased blood flow within the cyst. Depending on the specific situation, interventions might involve percutaneous drainage of the cyst, where fluid is removed with a needle, or surgical removal of the cyst. Surgical options can range from laparoscopic cystectomy, which removes only the cyst while preserving the organ, to more extensive procedures if warranted. A septated cyst is not inherently malignant, but its characteristics guide the appropriate medical evaluation and management.