Understanding Breast Ultrasound: Applications, Procedure, and BI-RADS Reporting

Breast ultrasound is a non-invasive imaging modality widely used in the evaluation of breast tissue. It plays a crucial role in the early detection and diagnosis of breast abnormalities, particularly in women with dense breast tissue where mammography may be less sensitive. This article provides an in-depth look at breast ultrasound, its indications, how it is performed, and how to interpret and report findings using the BI-RADS system.

Breast Sonographer

What is Breast Ultrasound?

Breast ultrasound is an imaging technique that uses high-frequency sound waves to produce real-time images of breast tissue. It is a valuable diagnostic tool that aids in the characterization of breast lesions, differentiation of cystic from solid masses, and guidance for interventional procedures such as biopsies.

Indications for Breast Ultrasound

Breast ultrasound is recommended in various clinical scenarios, including:

• Evaluation of palpable breast lumps: When a patient notices a lump or abnormality in the breast, ultrasound is often used to determine if the lump is solid or fluid-filled (i.e., a cyst). This is crucial for distinguishing benign conditions from potentially malignant ones.

• Further assessment of abnormal mammography or MRI findings: To provide additional characterization. For women with dense breast tissue, mammography alone may not provide a clear image of the breast. Ultrasound can be used in such cases to offer additional information or supplement Mammography.

• Screening in high-risk patients: Particularly in women with dense breasts or a strong family history of breast cancer.

• Guidance for interventional procedures: Such as ultrasound-guided biopsies and cyst aspirations. Ultrasound is frequently used to guide the placement of a needle during breast biopsy procedures. This helps ensure accurate targeting of the area of concern for tissue sampling.

• Evaluation of breast implants: For women with breast implants, ultrasound can help assess the integrity of the implant and check for complications like rupture or leakage.

• Monitoring known benign lesions: To ensure stability over time. In patients diagnosed with breast cancer, ultrasound can be used to monitor the progression or response to treatment, especially when combined with other imaging techniques.

• Evaluation of Symptoms: Ultrasound may also be used to evaluate other breast symptoms such as pain, skin changes, or nipple discharge.

Medical Applications of Breast Ultrasound

Breast ultrasound offers several important medical applications, particularly in the diagnosis and management of breast conditions:

• Differentiation of Solid and Cystic Masses: Breast ultrasound is particularly effective in distinguishing between solid masses and fluid-filled cysts. Cysts are usually benign and do not require surgical intervention, while solid masses may warrant further investigation.

• Staging of Breast Cancer: Ultrasound helps assess the size of breast tumors, as well as their relationship to surrounding tissues, such as the chest wall or lymph nodes. This information is critical in staging breast cancer and planning treatment.

• Assessment of Axillary Lymph Nodes: Ultrasound is also used to examine axillary lymph nodes (under the arm) for signs of metastasis in patients with breast cancer.

• Evaluation of Inflammatory Conditions: Breast ultrasound is helpful in diagnosing inflammatory conditions like mastitis or abscesses, which often present with redness, pain, or swelling in the breast.

How to Perform a Breast Ultrasound

Performing a breast ultrasound requires expertise in sonographic techniques and a thorough understanding of breast anatomy.

The procedure involves:

1. Patient Preparation:

   • The patient is typically positioned in a supine or oblique position with the arm raised behind the head to optimize visualization.

   • A water-based gel is applied to the skin to facilitate sound wave transmission.

2. Scanning Technique:

   • A high-frequency (7–15 MHz) linear transducer is used.

   • The entire breast, including the axillary region, should be scanned systematically in radial or overlapping transverse/longitudinal planes.

   • Compression techniques may be used to differentiate real masses from artifacts.

3. Doppler Evaluation:

   • Color Doppler imaging can assess vascularity, aiding in distinguishing benign from malignant lesions.

4. Duration: The entire procedure typically takes between 15 and 30 minutes, depending on the complexity of the examination.

5. After the Exam: There is no downtime after a breast ultrasound, and patients can resume normal activities immediately.

BI-RADS Classification in Breast Ultrasound

The Breast Imaging-Reporting and Data System (BI-RADS) provides standardized reporting and categorization of breast imaging findings. This system helps in clinical decision-making and risk stratification.

BI-RADS Categories for Breast Ultrasound

• BI-RADS 0: Incomplete - Additional imaging or prior comparisons needed.

• BI-RADS 1: Negative - No abnormal findings.

• BI-RADS 2: Benign - Includes simple cysts, fibroadenomas, and other clearly non-malignant findings.

• BI-RADS 3: Probably benign - Lesions with <2% chance of malignancy; follow-up recommended.

• BI-RADS 4: Suspicious abnormality - Biopsy should be considered; further divided into:

  • 4A: Low suspicion (2–10% malignancy risk)

  • 4B: Moderate suspicion (10–50% malignancy risk)

  • 4C: High suspicion (50–95% malignancy risk)

• BI-RADS 5: Highly suggestive of malignancy - >95% chance of cancer; biopsy strongly recommended.

• BI-RADS 6: Known biopsy-proven malignancy - Used for confirmed cancer awaiting treatment.

Reporting a Normal or Abnormal Breast Ultrasound

A structured ultrasound report should include:

1. Patient and Examination Details:

   • Name, age, indication for the scan, and date of the study.

2. Description of Findings:

   • Breast composition (homogeneous, heterogeneous, dense tissue, etc.).

   • Any masses, their size, shape, orientation, margins, echogenicity, and vascularity.

   • Presence of cysts, calcifications, or architectural distortions.

3. BI-RADS Assessment Category:

   • Assign an appropriate BI-RADS category based on imaging features.

4. Recommendations:

   • Follow-up, biopsy, or referral for further evaluation if necessary.

How to Report a Normal or Abnormal Breast Ultrasound

The process of reporting breast ultrasound findings is essential for ensuring accurate diagnosis and treatment planning. A Breast Sonographer typically interprets the ultrasound images and provides a detailed report.

The report will include:

1. Normal Ultrasound:

   • No Masses or Abnormalities: A report for a normal ultrasound may indicate that the breast tissue appears homogeneous and there are no visible masses, cysts, or abnormal lymph nodes.

   • Benign Findings: If a small, benign cyst or fibrocystic changes are present, these findings will be described as non-cancerous, and the patient may be advised to undergo regular follow-up.

     
     

2. Abnormal Ultrasound:

   • Solid Masses: If a solid mass is identified, the radiologist will describe its size, shape, margins, and internal characteristics (e.g., whether the mass is hypoechoic, or darker on the ultrasound image, suggesting it may be solid and potentially cancerous).

   • Suspicious Features: Features such as irregular margins, increased vascularity, or a spiculated shape may raise concern for malignancy. The radiologist may recommend further diagnostic workup, such as biopsy or additional imaging.

   • Lymph Node Enlargement: If enlarged lymph nodes are detected, especially in the axilla, the radiologist will assess whether they appear abnormal, which may indicate metastatic spread in cases of breast cancer

Conclusion

Breast ultrasound is an indispensable tool for evaluating breast abnormalities, guiding interventions, and supplementing mammography. Proper technique and standardized reporting using the BI-RADS system enhance diagnostic accuracy and patient care. Understanding how to interpret and report ultrasound findings ensures timely and appropriate management of breast lesions.

Always consult with a healthcare provider to determine the most appropriate imaging strategy based on individual risk factors and concerns.