Bhatt, Asha A.

AbstractClinically, acute mastitis presents as a red, swollen, and painful breast. Targeted ultrasound can be performed to evaluate the extent of infection and for an underlying abscess. Noncomplicated mastitis or a small fluid collection may respond to oral antibiotics without further intervention, but a larger or more complex abscess may require single or serial percutaneous aspiration. Breast infections, particularly those complicated by an abscess, can have a prolonged clinical course, and close follow-up is required. Since the clinical presentation and imaging features of acute infectious mastitis can overlap with other etiologies, such as inflammatory breast cancer and idiopathic granulomatous mastitis, a percutaneous biopsy may be indicated to accurately diagnose patients.

Ultrasound‐guided breast biopsies can be challenging to perform, especially when the target is adjacent to the nipple, skin, or implant or when the target is small and in very posterior, dense fibroglandular tissue. Oftentimes, a slightly modified approach can result in a diagnostic biopsy specimen with minimal complications. After a brief review of basic techniques for ultrasound‐guided breast biopsies that includes a review of conventional breast biopsy devices, a presentation of procedural modifications and techniques to consider for more challenging cases is described. In particular, novel open‐trough and tandem‐needle techniques are detailed. Several cases using these techniques are then presented.

When a breast lesion is seen on only magnetic resonance imaging (MRI) and needs to be excised, pre-operative MRI-guided radioactive seed localization (RSL) is preferred. However, MRI safety and radiation safety issues associated with the inability to recover a potentially lost seed in the MRI scanner room (Zone IV) have precluded this in the past. This manuscript provides a protocol for MRI-guided RSLs that meets MRI safety and radiation safety criteria established by the American College of Radiology and the Nuclear Regulatory Commission. To the authors’ best knowledge, this has never been published in the literature. The complete protocol is provided.

Objective: The purpose of this study is to assess the outcomes of symptomatic and asymptomatic solitary dilated ducts detected on mammography, ultrasound, and MRI. Methods: All cases of isolated solitary dilated ducts between January 1, 2009 and December 31, 2016 in non-lactating females were reviewed. Clinical data, including patient’s age, breast cancer history, and pathology results were collected. Imaging was reviewed, and indication for the exam, breast density, maximum diameter of the dilated duct on ultrasound, presence of an intraductal mass, presence of intraductal vascularity, presence of intraductal echogenicity, and subareolar or peripheral location of the dilated duct were recorded. Results: 87 cases of solitary dilated ducts were assessed in this study, of which 3 were malignant, resulting in a positive predictive value of 3.5% (3/87). No malignancy was identified in asymptomatic screening patients. The three malignant cases were seen in patients presenting with a palpable lump (n = 1) or bloody nipple discharge (n = 2). There was a statistically significant association observed between the dilated duct diameter (p = 0.049) and presence of intraductal vascularity (p = 0.0005) with presence of malignancy. Conclusion: Rate of malignancy is low in solitary dilated ducts, especially among asymptomatic patients. Patient’s presenting with clinical symptoms, larger dilated duct diameters, and/or intraductal vascularity may require additional evaluation including biopsy to exclude malignancy. Advances in knowledge: Clinical and imaging factors can assist in better identifying patients with solitary dilated ducts who should undergo biopsy.

Pseudoaneurysm (PSA) formation is a potential complication of breast biopsies. Ultrasound is the most common imaging modality used for evaluation and treatment of a PSA. Color Doppler images show a cystic structure with swirling flow inside in a “to‐and‐fro” pattern. Treatment options for PSA include observation, ultrasound‐guided focused compression, thrombin injection, open surgical repair, and percutaneous embolization. The risks and benefits of these treatment options will be discussed in the following cases.

Objective: The purpose of this study is to evaluate diffusion weighted magnetic rsonance imaging (MRI) acquisitions in delineating posterior extent of breast tumors and in predicting chest wall invasion prior to treatment. To our knowledge, there has not been any literature specifically evaluating the utility of diffusion-weighted acquisitions in chest wall invasion of breast tumors. Materials and Methods: A retrospective review of our breast imaging database for keywords “chest wall invasion” and “breast MRI” was performed over the last 14 years. Diffusion sequences, T1 sequences (pre and post contrast), and T2 sequences were evaluated. Apparent diffusion coefficient (ADC) values in tumor and chest wall were assessed. Imaging findings were correlated with surgical pathology. Results: 23 patients met inclusion criteria. All 23 had loss of fat plane on T2 sequences. 22/23 had loss of fat plane on postcontrast T1 sequences. Pectoralis muscle enhancement was present in 19/23 (83%) tumors and chest wall enhancement was present 9/23 (39%) tumors. Qualitative restricted diffusion within the pectoralis muscle was present in 18/23 (71%) tumors and in the chest wall was present in 8/23 (35%) tumors. Mean ADC values were 1.15 s/mm2 in the tumor and 1.29 s/mm2 in the chest wall. Sensitivity, specificity, positive predictive value and negative predictive value were 100%, 36%, 63%, and 100% for chest wall enhancement respectively and 69%, 36%, 61%, and 80% for chest wall diffusion-weighted imaging restriction respectively. Conclusion: Diffusion weighted sequences can be helpful in characterizing chest wall invasion of breast tumors.

Preoperative localization of breast malignancies using traditional ultrasound and digital techniques can be challenging, particularly after neoadjuvant chemotherapy when the target is not conspicuous. The purpose of this paper is to pictorially present nontraditional techniques that have been helpful in preoperative localization before surgery. We will discuss techniques for breast lesion localization using computed tomography (CT) and magnetic resonance imaging (MRI) as well as axillary lymph node localization using tomosynthesis, CT, and MRI.