The tongue is a very vascularised tissue. Nevertheless, the ultrasonic partial glossectomy was a fast, easy and bloodless procedure. However, this lingual resection technique should be performed on small tissue layers (around 5 mm) in order to achieve the most efficient outcome possible and to insure an efficient hemostasis of the lingual vessels (Figure 1). This procedure allowed a fine removal of the tongue tumour.
In our series, no operative bleeding occurred, though a few cases of bleeding have been recorded in the medical literature [8, 9]. The reported cases were easily controlled. Therefore, even if the quality of the harmonic hemostasis had been shown, as for the blood vessels of less that 3 mm in diameter (which is the case for the lingual vessels, even at the base of the tongue), with a pressure inferior to 226 mmHg [10], this dissection can be complicated by bleedings requiring vessels ligature and/or additional monopolar or bipolar hemostasis.
Late postoperative bleeding was relatively frequent in our series (2 cases out of 18 partial glossectomies) that had not been previously found in literature. They all happened after the fifth postoperative day, at the time when the scar fell. These lingual bleedings, stemming from the lingual artery, were severe and they made it difficult to intubate the patient without the risk of blood inhalation at the time of the anaesthetic induction. For this reason, we had to carry out hemostasis without anaesthetic in 1 of the 2 cases. In both cases the bleeding arose on the cut of the tongue. The section-cauterization of the lingual artery was performed in a muscular, elastic, contractile and mobile structure that can put tension on the cut zone and therefore weaken it. Moreover, this cut zone is superficial, and it can come in contact with saliva and food, thus weakening the coagulum. These incidents of late postoperative lingual bleedings, like the palatine tonsillectomy bleedings incidents, are a classic complication at the moment when the scar fell. Thus, we recommend to ligate the lingual artery when it can be visualized during the tongue dissection and we encourage the hospitalization of patients for at least seven days after the partial glossectomy.
The ultrasonic partial glossectomy provoked only little pain and patients took simple analgesics (no morphine except in one case) to control the pain. The use of the harmonic scalpel is known to give little postoperative pain, much less than the hemostasis carried out with the help of monopolar or bipolar cauterization [11–13]. This reduced pain is due to the fact that ultrasonic hemostasis is carried out at a low temperature between 50 – 100°C compared to 150 – 400°C for the monopolar and bipolar electrocoagulation [12]. It thus results in a slight thermal diffusion of adjacent structures. This hemostasis is performed at a low energy and temperature leading to less postoperative pain and faster healing [11–14].
Because the tongue dissection was performed without bleeding, all the tumour removals have been carried out with an acceptable margin resection (which mean was 16 mm) and no recurrence appeared. The pathologist can hardly interpret the cut zone because of the necrosis induced by the hemostasis. The use of the harmonic scalpel reduced this zone to 0.8 mm on average (Figure 2). But this section did not prevent the surgeon from performing the re-cut on the border of the tumor. This measurement is in accordance with the data previously reported in the literature (0 to 2 mm). It is a very weak layer, especially compared to the layer burnt by the monopolar and the bipolar cauterization which provokes, at the level of the cut, a layer of necrosis of 6 to 8 mm [10]. Thus, the use of the harmonic scalpel facilitated the job of the pathologist in interpreting the margins of the resection.
The overall cost of the consumable materials (essentially represented by the price of a pair of harmonic scissors) was largely compensated for by the reduction of the operative time which leads to a reduction of costs for the rental of the surgical box and the surgical team [9]. The price for the generator was not counted in this study because it is a piece of technology used for several specialties in our hospital (visceral surgery, urology) and thus its price would be calculated in a large number of surgical interventions.