It is easy to make anecdotal claims for the efficacy of new forms of treatment based on the short term results in a small number of patients. Many authors have done this for endoscopic laser therapy in the gastrointestinal tract. It is very much more difficult to carry out a comprehensive assessment of the short and long term effects of new techniques and to compare these with the results of alternative treatments for the same diseases. This book, from one of the world's leading departments of gastroenterology, describes and analyses the largest series of patients yet reported from one centre treated endoscopically with the NdYAG laser for gastrointestinal disease. The follow up extends over 8 years and the results are impressive. Some of the early claims for laser therapy have been validated, others have not, but the real value of the book is that we now have a large amount of well organised data on which to judge the merits of laser therapy. Medical laser techniques are in their infancy and the potential for future develop­ ment is enormous, but ideas on current applications have been consolidated and that is essential before the next concepts evolve. This book has taught us how to walk. The world is now ready to learn to run! S. G. Bown, Director National Medical Laser Centre London Contents INTRODUCTION 3 Introduction and purpose of the study 5 1 General aspects of laser 6 1. 1.

Inhalt

and purpose of the study.- 1 General aspects of laser.- 1.1. The properties of laser.- 1.1.1. Thermal action of laser.- 1.2. Types of laser.- 1.3. Clinical application of laser.- 1.3.1. Parameters of effective haemostasis.- 1.3.2. Endoscopic modalities and laser treatment for haemostasis.- 1.4. New developments in laser application.- 1.5. Conclusion.- 2 Application of laser energy in gastroenterology.- 2.1. Laser treatment in acute bleeding.- 2.2. Laser treatment of variceal bleeding.- 2.3. Laser treatment of non-variceal bleeding.- 2.3.1. Divergent selection criteria.- 2.3.2. Parameters for optimal haemostasis and optimal safety.- 2.4. Results of laser treatment.- 2.4.1. Haemostasis with the argon laser.- 2.4.2. Haemostasis with the Nd:YAG laser.- 2.4.3. Overall considerations.- 2.5. Comparison of laser with other endoscopic modalities in haemostasis.- 2.5.1. Experimental studies.- 2.5.2. Clinical studies.- 2.6. Conclusion and proposition for treatment of acute bleeding.- 3 Technical prerequisites, safety considerations and treatment settings in Amsterdam.- 3.1. Technical prerequisites.- 3.1.1. Laser equipment.- 3.1.2. Endoscopes.- 3.1.3. Auxilliary instruments.- 3.2. Safety considerations.- 3.3. Laser settings and treatment procedure.- 3.3.1. Mucosal vascular abnormalities as potentially bleeding lesions.- 3.3.2. Tumour treatment.- 3.4. Technical problems.- 3.5. Conclusion.- I: Haemostasis.- 4 Mucosal vascular abnormalities as potentially bleeding lesions in gastroenterology.- 4.1. Classification of vascular lesions.- 4.2. Mucosal vascular abnormalities.- 4.2.1. Pathology.- 4.2.2. Aetiology and pathogenesis.- 4.3. A ngiodysplasia.- 4.3.1. Symptomatology and associated diseases.- 4.3.2. Diagnosis.- 4.4. Telangiectasia.- 4.5. Treatment of mucosal vascular abnormalities.- 4.5.1. Surgery.- 4.5.2. Endoscopic treatment.- 4.5.3. Treatment in the presence of associated valvular heart disease.- 5. Laser treatment of mucosal vascular abnormalities as potentially bleeding lesions.- 5.1. Design of the study.- 5.1.1. Patients and methods.- 5.1.2. Treatment and technique.- 5.1.3. Evaluation of the results.- 5.2. Results of the study: descriptive part.- 5.2.1. Demographic data.- 5.2.2. Diagnostic and investigational data.- 5.3. Results of the study: laser treatment.- 5.3.1. Angiodysplasia.- 5.3.2. Telangiectasia.- 5.3.3. Haemangioma.- 5.4. Results of the study: outcome without laser intervention.- 5.5. Discussion.- 5.6. Conclusion.- II: Tumour Ablation.- 6 Laser treatment of colorectal adenomas.- 6.1. Introduction.- 6.1.1. Adenomas of the colon.- 6.1.2. Familial polyposis col.- 6.2. Prospective study of patients with colorectal adenomas and rectal stump polyps between 1979 and 1987.- 6.2.1. Preliminary results (1979-1984).- 6.2.2. Patients and methods (1979-1987).- 6.3. Results.- 6.3.1. Group 1, 150 patients with colorectal adenoma.- 6.3.2. Group 2, 30 patients with familial polyposis col.- 6.4. Follow-up observations.- 6.4.1. Effect of laser treatment after short and long exposure.- 6.4.2. Patients with malignant degeneration.- 6.5. Discussion.- 6.6. Conclusion.- 7. Palliation of gastro-oesophageal cancer.- 7.1. Introduction.- 7.2. Surgical treatment.- 7.2.1. Oesophageal cancer.- 7.2.2. Gastric cancer.- 7.3. Radiotherapy and chemotherapy.- 7.3.1. Oesophageal cancer.- 7.3.2. Gastric cancer.- 7.4. Endoscopic procedures.- 7.5. Conclusion.- 8 Laser photoablation in the palliation of gastro-oesophageal cancer.- 8.1. Design of the study.- 8.1.1. Patients and methods.- 8.1.2. Patient preparation and treatment.- 8.2. Evaluation of the results.- 8.3. Results.- 8.3.1. Demographic data.- 8.3.2. Treatment data.- 8.3.3. Adverse effects of laser treatment.- 8.4. Discussion.- 8.5 Conclusion.- 9. Treatment modalities in colorectal cancer.- 9.1. Introduction.- 9.2. Operative treatment: general surgery.- 9.2.1. Elective surgery.- 9.2.2. Emergency surgery.- 9.2.3. Palliative surgery.- 9.3. Operative treatment: local surgery.- 9.4. Radiotherapy.- 9.5. Chemotherapy.- 9.6. Laser photocoagulation.- 10. Laser photocoagulation in the palliation of colorectal cancer.- 10.1. Design of the study.- 10.1.1. Patients and methods.- 10.1.2. Patient preparation and treatment.- 10.2. Evaluation of results.- 10.3. Results.- 10.3.1. Demographic data.- 10.3.2. Treatment data.- 10.3.3. Adverse effects of laser treatment.- 10.4. Discussion.- 10.5. Conclusion.- 11. Laser photoablation of early gastrointestinal cancer.- 11.1. Introduction.- 11.2. Design of the study.- 11.3. Evaluation of the results.- 11.4. Results.- 11.4.1. Early gastric cancer.- 11.4.2. Early colonic cancer.- 11.5. Discussion.- 11.6. Conclusion.- 12. Laser photocoagulation in the small intestine.- 12.1. Design of the study.- 12.1.1. Patients, methods and technique.- 12.1.2. Evaluation of the results.- 12.2. Results.- 12.3. Discussion.- Appendix I.- Questionnaire on Nd:YAG laser treatment of mucosal vascular abnormalities.- Appendix II.- Questionnaire on Nd:YAG laser treatment of gastro-oesophageal cancer.- Appendix III.- Questionnaire on Nd:YAG laser treatment of colorectal cancer.- Appendix IV.- Data of patients unfit for laser treatment of angiodysplasia.- Summary.- Samenvatting.- References.