Interventional procedure overview of Balloon cryoablation for treating Barrett's oesophagus

The condition

The oesophagus is a muscular tube, connecting the mouth and stomach. In Barrett's oesophagus (BE) the cells lining the lower part of the oesophagus change, becoming more like the cells lining the intestines (intestinal metaplasia). The changed cells can become abnormal (dysplasia) over time. There is a small chance of the abnormal cells becoming cancer. Treatment may be offered to try and remove the affected tissue. This aims to lower the cancer risk.

Current practice

Current management may include lifestyle change, acid-suppressing medicines, endoscopic mucosal resection, endoscopic submucosal dissection, ablative therapies and surgery. Ablative therapies include radiofrequency ablation (RFA), photodynamic therapy, argon plasma coagulation, laser ablation, multipolar electrocoagulation and cryotherapy.

Those with BE whose cells are dysplastic should be offered treatment. However, treatment options depend on the grading of dysplasia. RFA is currently recommended as first-line treatment for BE with low-grade dysplasia (LGD). Endoscopic resection is recommended for high grade dysplasia (HGD) and oesophageal adenocarcinoma.

Unmet need

Current treatment options for BE may not always be feasible or suitable. RFA should be avoided in those with severe co-morbidities (such as cardiopulmonary disease) or those unable to discontinue anticoagulation therapy. It may also be unfeasible because of uneven BE surface, or oesophageal strictures (precluding passage of the RFA catheter). Endoscopic resection may be unsuitable for people with coagulation disorders, portal hypertension, and those unable to discontinue anticoagulation therapy. Endoscopic resection may also be difficult for longer BE segments, or in the absence of an endoscopically visible lesion.

Cryoballoon ablation (CBA) may cause less pain than other ablation techniques in some people. It may also be better tolerated or appropriate for some people with comorbidities.

The procedure

The aim of CBA is to destroy (or 'ablate') the abnormal cells lining the oesophagus. Sedation is usually used. A balloon catheter is inserted through an endoscope, aligned with the affected tissue and inflated. Nitrous oxide gas is sprayed through a radial diffuser head within the balloon aimed at the abnormal tissue. Cryogen is used to ablate (freeze) the unwanted tissue. The extreme cold destroys the tissue. The nitrous oxide gas remains fully contained within the balloon and exits outside the body through the proximal end of the catheter. The ablation sequence is repeated until all abnormal cells are destroyed. Multiple ablations can be done in one session without removing the balloon. Repeat endoscopy will be scheduled 8-12 weeks following the procedure to check if the unwanted tissue has been destroyed. If evidence of unwanted tissue is found, retreatment may be considered.