The use of a dura mater patch to cover oesophageal defects of different sizes: An experimental study in chickens

Objective: To find out the optimal size of full thickness oesophageal defec ts that can be repaired with patches of Tutoplast(R) Dura (solvent dehydrat ed human dura mater in the form of absorbable collagen). Design: Experimental study. Setting: Teaching hospital, Greece. Material: 96 female Hubbard chickens in four groups of 24. Interventions: In the three experimental groups longitudinal defects were m ade in the cervical oesophagus 30 x 5, 10, or 15 mm and covered with Tutopl ast(R). Subgroups of 6 chickens were weighed, had a barium swallow examinat ion, and were then killed at 2, 4, 6, and 8 weeks. The oesophagus was remov ed and examined histopathologically. Main outcome measures: Weight, extent of healing macroscopically and micros copically. Results: All chickens that had had defects 30 x 15 mm in size died between days 5 and 10, and the oesophagus in all cases was obstructed by food. Ther e were no deaths or complications in the other three groups, and no evidenc e of dysphagia on barium swallow. In chickens with defects of 30 x 5 and 30 x 10 mm the prosthetic material gradually disappeared, and they healed wel l. Conclusions: Defects in the chicken's cervical oesophagus larger than 30 x 10 mm cannot be repaired with a Tutoplast(R) patch, but smaller defects can . Further studies are needed to clarify the mechanisms of healing.