Lasers in gastroenterology

Figure 1 Advanced, obstructing carcinoma of the oesophagus: A, at presentation; B, during laser therapy; C, after two endoscopic laser treatments. The oesophageal lumen has been re-opened and the patient's dysphagia has been relieved.

Figure 2 Photodynamic therapy for dysplasia in Barrett's oesophagus: (A) prior to therapy, columnar lined mucosa is seen at endoscopy. Dysplasia is not visible, but has been confirmed histologically; (B) one day after treatment, there is widespread sloughing of the oesophageal mucosa; (C) one month later, the oesophagus has completely healed with some regeneration of squamous mucosa.

Figure 3 Photodynamic therapy for treatment of a small pancreatic cancer. Three days after photosensitisation with mTHPC, light is delivered to the tumour via fibres passed through needles positioned percutaneously under CT guidance. (Reproduced with permission from Bown SG, Br Med J, 1998; 316: 754-757)

Figure 4 CT scans (A) before and (B) one week after PDT for pancreatic cancer. The tumour surrounding the biliary stent seen in the first scan has been replaced by a low density area of necrosis.