Can the proportions of obtained maximal dilatation with the different types of bougies be evaluated?
F. Vicari (Nancy)
No or at least so far as we know and this is especially true if we only consider the stenoses due to gastroesophageal reflux ( GER).
A prospective study could be done, but would be more interesting in the view of comparing bougies and balloons rather than comparing different bougies.
Indeed, through-the-scope balloons being easier to use, supplant the bougies more and more. Nevertheless, in some cases, the stricture is such that only a fine and rigid bougie can progress on the guide wire when a flat balloon meets resistance at the beginning of the strictured segment. In this particular case, dilatation may be completed either with bougies only or alternately with the balloon.
In fact, the choice of the type of bougies or balloons used is guided by the habits (the "craft") of the operator: his ability for one or the other technique as well as the degree of the stenosis and for how long it has been present.
Aware of this notion, Aste et al.  prefer to use the balloon for these advanced stages because it is more progressive and easier to control. For Ekberg , the balloon virtually does not present any risk of esophageal rupture which is not the case with the bougies (0 to 9% of accidents).
Whatever the method used, it is certain that a sufficient dilatation of 15 mm can be obtained. This result is generally achieved with Hurst and Maloney bougies as well as Eder-Puestow metal olives, but these techniques have now been abandoned due their risk of complication.
Because of this risk, Mainguet , in 1978, recommended a method of dilatation by means of laminaria which is a safe, low costing and efficient method with a dilation generally over 13 mm.
The advent of Savary-Gilliard bougies made of polyvynil chloride allowed a widespread use of the dilatation technique on guide wire. In 1985, Monnier et al. reported an experience of 239 dilatations of benign stenoses (113 patients) with no perforation nor severe hemorrhage rendering all previous techniques obsolete and only preserving as alternatives the laminaria technique described by Mainguet, Lemarchal and the Owman-Lunderqvist balloons.
Eventhough no report in the literature have been found concerning the proportions of maximal dilatation obtained with the different types of bougies, many publications exist comparing bougies and balloons, the more recent being Graham's study .
At the initial visit, the degree of dysphagia was assessed: 6 stages from 0 (total dysphagia) to 5 (normal swallowing). Other clinical factors (reflux, pyrosis) or endoscopic factors (size of the stenosis, stage of the associated esophagitis, hiatal hernia) were also mentioned. Then, during the dilatation process, patient's discomfort was graded (from 0 to 3).
A comparison was made between the Savary-Gilliard bougies and Rigiflex balloons from Microvasive/Boston Scientific Corp. The defined end-point was the passage of a 45 F dilator, i.e. 15 mm.
Then all patients were given the standard anti-reflux instructions measures and/or an anti-H2 treatment. The follow-up and evaluation of the results were carried out for 24 months which makes this work particularly interesting with visits at 8 days, 1 month, 3 months and 24 months.
On the 8th-day visit, all patients underwent an X-ray test consisting of swallowing barium pills of increasing diameter (from 8 to 12 mm).
On the following visits, patients were asked to report about their ability to swallow graded according to the 6-point dysphagia scale. If needed, a redilatation was done according to the same procedure.
On 36 selected patients, 34 were enrolled in the study: 17 in each group. In all cases, a 15 mm dilatation was achieved. With the Savary bougies, 1,7 ± 0.2 sessions were needed as only 1.1 ± 0.1 sessions were sufficient with Microvasive balloons (p < 0.5).
A life-table analysis showed that the recurrence rate of the strictures was identical in both groups during the first year but significantly lower in the group dilated with balloons.
Apart from this advantage, the authors also reported a better comfort for the patients dilated with balloons.
In conclusion, this study shows a good demonstration of the superiority of balloons compared with Savary bougies especially if long-term evaluation is considered. Now it would be interesting to determine which category of patients has a risk of recurrence and the best way to prevent it. Saeed seems to identify patients who needed more dilatation sessions at the beginning but larger series may be necessary to support such a statement.
1. Jeyasingham K. What is the histology of an esophageal stricture before and after dilatation? In: Giuli R, Tytgat GNJ, DeMeester TR, Galmiche JP, eds. The esophageal mucosa. Amsterdam: Elsevier, 1994:335-339.
3. Aste H, Conio M, Picasso M. Are there histological characteristics that might help in selecting the dilating equipment or dilatation techniques? In: Giuli R, Tytgat GNJ, DeMeester TR, Galmiche JP, eds. The esophageal mucosa. Amsterdam: Elsevier, 1994:339-342.
7. Zahid A, Saeed MD, Carolyn B, Winchester BSN, Ferro PS, Michaletz PA, Schwartz JT, Graham DY. Prospective randomized comparison of polyvinil bougies and through-the-scope balloons for dilatation of peptic strictures of the esophagus. Gastrointest Endosc 1995;41,3:189-195.