Structural deterioration of prosthetic oesophageal tubes: an in vitro comparison of latex rubber and silicone rubber tubes

A case of neglected silicone tube in lacrimal duct for 20 years

Purpose

To report a case of prolonged placement of a lacrimal silicone tube for 20 years, with evaluation of the lacrimal duct using lacrimal micro-endoscopy and inspection of deformation of the lacrimal tube.

Observations

This study involved a case of dacryocystitis in which a silicone tube had been placed in the patient 20-years previous and that was treated conservatively. Although granulation tissue formation due to dacryocystitis in the lacrimal duct was observed under lacrimal micro-endoscopy, subjective and objective resolution of symptoms, including granulated tissue formation, was achieved after removal of the silicone tube and conservative medical treatment. Follow-up examinations performed over a 12-month period post treatment revealed no recurrence of epiphora or anatomical obstruction. Inspection of the lacrimal tube using the tension test revealed minimal changes in the tube in situ for 20 years.

Conclusions and Importance

The findings in this case suggest both the lacrimal system and the silicone tube are tolerant to prolonged intubation, as long as the tube had been placed properly with careful observation. Our findings may encourage physicians to consider prolonged intubation for select cases of nasolacrimal duct obstruction.

Artificial esophagus with peristaltic movement

In this study, we have developed an artificial esophagus simulating peristaltic movement with the use of a nickel-titanium shape memory alloy (NiTi-SMA) actuator. Serial pairs of NiTi-SMAs were placed around a Gore-Tex vascular graft in a helical position such that they obliterated the lumen of the vessel when they contracted. In an animal experiment using a goat, the cervical esophagus was resected over a length of approximately 20 cm. The artificial esophagus was anastomosed with the remaining cervical esophagus. When a direct current of 500 mA at 5 V was applied to the NiTi-SMAs, the first pair of the NiTi-SMA contracted. The following pairs of the NiTi-SMAs contracted consecutively. The entire contraction of the artificial esophagus was similar to the esophageal peristaltic movement observed by x-ray examination in humans. The results showed the possibility that the artificial esophagus could function as an artificial esophagus having peristaltic movement.

Palliative intubation of oesophagogastric neoplasms at fibreoptic endoscopy

Of one hundred and twenty-one patients with neoplastic obstruction of the oesophagus or cardia 118 underwent palliative intubation at fibreoptic endoscopy on a total of 135 occasions. Sixty had adenocarcinoma, 49 had squamous carcinoma, and in nine the oesophagus was involved by a growth arising elsewhere. Satisfactory swallowing ws restored in 112 patients. Thirteen patients died in hospital shortly after the procedure. Five fatal and 10 non-fatal perforations were sustained in 135 intubation procedures. Complications of tube function included food blockage on 26 occasions, tumour overgrowth on seven occasions, displacement on 16 occasions, disappearance of the tube in two patients, and late oesophageal perforation on nine occasions. Fifty-six patients survived for three months, 33 for six months, and 10 for a year after intubation. Comparison with series in the literature of patients who underwent surgical palliative intubation suggests that endoscopic palliation has lower mortality and morbidity, and an increased survival time, and is now the method of choice for palliation of oesophagogastric neoplasms.