A highly angulated trajectory for a liver dome lesion on the capsule and adjacent to the diaphragm

A 76-year-old man with colorectal cancer and a history of both resection and ablation of liver metastasis presented with 2 CRLMs (Segment V, Segment VIII). Due to the highly challenging location (subcapsular, highly angulated trajectory, adjacent to the diaphragm) of one of the lesions, MWA using CAS-One IR was used to treat the patient. The planning module and the fixed arm of CAS-One IR enabled an effective treatment so close to a critical structure. 10mm margin was achieved on a follow up scan and no intraprocedural complications were reported. 

Planning scan in MPR view with vessel segmentation and planned trajectory on the more challenging lesion visible 

Name: Daniel Østergaard & Åsmund Avdem Fretland

Institution: Oslo University Hospital, Rikshospitalet 

Patient sex, age:  Male, 76 year old 

Initial condition:

• Patient diagnosed with colorectal cancer in 2019
• Patient previously underwent partial resection and ablation of liver metastasis
• On a recent CT scan, also confirmed by MRI, two new liver lesions discovered in segment V and VIII
• The liver dome lesion in segment VIII, directly on the capsule, presented a significant challenge due to the trajectory needed to reach it, and the proximity to the diaphragm
• It was decided to using CAS-One IR to effectively, confidently, and quickly reach this challenging lesion as well as the one in segment V

Treatment: 

• Two single trajectories were planned and executed 
• Planned ablation zone was manually moved in the CAS-One IR software to manage the proximity to the diaphragm
• The procedure was performed under general anesthesia
• During accuracy-critical phases, a apnea was performed to minimize the risk of movement 
• Needle verification scan showed minimal lateral error, but a need for depth adjustment 
• After adjusting the depth of the needle, ablation was performed with the Medtronic Emprint HP generator and a 15cm needle 

Result:

• The lesion was successfully treated with stereotactic microwave ablation with sufficient ablation margins 
• No intraprocedural complications were observed
• A 6-month follow up scan is planned