Percutaneous Lung Biopsy Using Cone Beam CT With Virtual Guidance: a Randomized Control Trial

Image-guided percutaneous lung biopsy is an essential procedure in lung cancer management, where it is integral to confirming the diagnosis and determining tumour histology. In this era of personalized medicine where knowledge of specific cellular pathways and molecular characterization relies on obtaining optimal tissue sampling, the critical question is how to obtain a high-quality biopsy tissue sample that could be processed for various pathological assessment from a single, minimally invasive percutaneous image-guided approach.

An ideal percutaneous lung biopsy also needs to have a short procedure time with accurate needle placement to minimize the inherent risk of the procedure, including the stochastic effect of radiation, and injuries to structures resulting in pneumothorax, pulmonary hemorrhage, and air embolism, which could all be potentially life threatening. Previous studies have also shown that post-biopsy haemorrhage or pneumothorax requiring chest tubes insertion had worse outcome, increased length of hospital stays, and respiratory failure.

Since the 1970s, conventional Multi-detector CT (MDCT) has been the modality of choice in percutaneous lung biopsy, which requires repeated scanning of the target lesion during the procedure and the interventional radiologist entering and leaving the CT suite after each needle adjustment. Recent research has proposed CT fluoroscopy and cone-beam CT (CBCT) as alternative methods.

Virtual guidance has been developed to improve target visibility and access for these complex cases. This involves image registration where the real-time imaging dataset is matched to a reference dataset, where the position of a device is displayed on the current imaging dataset in real time. Syngo iGuideTM is a novel navigational software which has the potential for accurate needle guidance in percutaneous biopsy. More specifically, it plans a potential computed 3D needle path before the procedure, using the CBCT images. An integrated laser crosshair is also projected onto the patient's skin to indicate the entry point and angle of the needle at no additional radiation dose to the patient and staff. This 3D path can be transposed onto real time fluoroscopic images to guide the biopsy, thus potentially improves patients' safety due to more accurate needle placement.

Inclusion criteria

• Solitary or multiple lung lesions (solid or subsolid nodule, pulmonary infiltrate) ≥1cm

Exclusion criteria

• Patient <18 years old
• Patient not able to give informed consent
• Uncooperative patient who is unable to hold still or hold their breath for safe biopsy
• Lesions <1cm
• Lesions within 1cm of vital thoracic structures such as the great vessels and the mediastinum
• Peripheral lesions accessible to biopsy with ultrasound guidance