American Board of Internal Medicine (ABIM) Certification Practice Exam

What is an alternative to mediastinoscopy that has a sensitivity of 75%?

1. Endobronchial ultrasound

2. Percutaneous transthoracic CT-guided needle biopsy

3. Transesophageal echocardiography

4. Thoracotomy

The correct answer is: Percutaneous transthoracic CT-guided needle biopsy

The choice of a percutaneous transthoracic CT-guided needle biopsy as an alternative to mediastinoscopy with a sensitivity of around 75% is based on its effectiveness in diagnosing mediastinal lesions. This procedure allows for direct access to lung lesions through the skin and is guided by CT imaging, which enhances the precision of the needle placement. This method is particularly useful in patients who may have lesions that are accessible without the need for surgical interventions or in cases where the risks associated with surgical procedures are not justified. The sensitivity rate indicates that while it may not capture all cases, it can still provide valuable diagnostic information in a significant number of instances. In contrast, other options like endobronchial ultrasound usually have higher sensitivity rates, making them less comparable for this specific purpose. Transesophageal echocardiography is primarily used for cardiac visualization and has limited role in tissue diagnosis in the mediastinum. Thoracotomy is a surgical approach that is more invasive and typically reserved for cases requiring more comprehensive interventions, rather than diagnostic purposes alone. Thus, the percutaneous transthoracic CT-guided needle biopsy stands out as a viable alternative with a relevant sensitivity rate.