Feasability of human endobronchial imaging with a linear-array ultrasound catheter

Abstract

Purpose: To explore the feasability of imaging lung masses with a novel endobronchial linear-array transducer.

Method: We used a linear-array transducer of 7 F (2.3 mm in diameter) operating at a center frequency of 10 MHz for endobronchial imaging. We used the probe in 20 subjects with suspected lung cancer to identify and measure the tumor; to asses the tumor's sonographic characteristics, bronchial wall invasion, and presence of lymph nodes; to guide a transbronchial needle aspiration (TBNA); and to evaluate potential side effects.

Results: In all patients, the tumor was identified and the relationship with the bronchial wall correctly evaluated through the depiction of a 3-layer wall pattern. Bronchial wall invasion was suspected in 5 patients, small adjacent lymph nodes were detected in 3 patients, and a small pleural effusion was observed close to the lung lesion in 2 patients. The linear-array probe allowed the guidance of successful TBNA with no complications.

Conclusion: This feasibility study shows that the prototype probe can be used to depict pulmonary lesions and to guide biopsy nodes. Larger series are needed to validate its usefulness in clinical work-ups and patients management.