The conquest of salivary glands by a new endoscopic approach

Professor M. Wolfensberger, reprint and translated from “Schweiz Med Forum No 51/52 17.12.2003”.
(Translation review by Patrick Bradley, M.D., Nottingham, GB)

Introduction

Sialendoscopy is one of the most fascinating innovations introduced in the last few years in the field of Oto-laryngology, head and neck surgery. Sialolithiasis and sialadenitis is one of the most frequently presenting disorders of the salivary glands. The diagnosis is most frequently confirmed by radiology. Treatment of sialolithiasis ranges from the use of surgery – intra-oral extraction or external lithotripsy, and the more frequent performance of external excision of the gland. Sialendoscopy uses minimal invasive surgical techniques which allows for optical exploration of the salivary ductal system and extraction of the stones by a basket under endoscopic view. This technique of sialendoscopy incorporates diagnostic with therapeutic procedures, as the clinical findings dictates.

Fig 1 : Semi-rigid Outer diameter 1.3 mm, with working and rinsing channel. From the article « all in one », Marchal Sialendoscope.

Diagnostic Sialendoscopy

In patients considered with sialolithiasis, involving the submandibular or parotid glands, the diagnosis of the condition may include the use of ultrasound, sialography or an MR-sialogram.

Ultrasound when used is a non-invasive and cheap diagnostic technique, which has limits on its diagnostic abilities, stones that are greater in size 3 mm. The technique is very user dependant and thus has additional limitations. Sialography, which has been considered the “gold-standard” for diagnosis of Sialolithiasis, is being used less frequently, because its interpretation and correlation with pathology does not have a good correlation to patient’s symptoms. The MR-sialography allows for reconstruction of the salivary ductal system without the use of the need for Contrast or dye injection. This technique has also got disadvantages and may not be performed on all suitable patients.

Sialendoscopy was described for the first time in the early 90’s. This technique has been introduced in Geneva in 1995 and since then sialendoscopy has improved by research, improved optics and instrumentation so that it is now become standard and routine for the investigation of all patients that present with symptoms of salivary gland diseases and disorders. The endoscope in current use by Dr F Marchal developed in collaboration with Karl Storz Company is a semi-rigid scope that contains two channels; a rinsing and a working channel, with an external diameter of 1.3 mm. Dr Marchal and his collaborators have described their experiences and their experiences have been published in major Oto-laryngological journals (1 – 3).

The Technique

Sialendoscopy is performed routinely and ambulatory, with patients seated or lying down supine. After the application of local anaesthetic to the duct papillae, it is dilated so that it can accommodate the endoscope without causing trauma to the duct or cause pain to the patient. The endoscopy is performed by the use of a rinsing anaesthetic solution. This technique allows for anaesthesia of the ductal system, the ability of fluid to clear of the stones or concretments identified within the ducts, and also for rinsing the scope. The ductal system can be explored from the primary ducts to the secondary and even tertiary ducts, and allows for the identification of stones and ductal stenosis. Other pathologies may be identified using this technique and include polyps, and stenoses which cannot be detected by the previously described diagnostic tests. According to F. Marchal and P. Dulguerov (3), sialendoscopy has been possible in 98% of cases performed on 450 cases studied. The procedure lasts between 12 – 40 minutes, and the difficulties are usually associated with small ductal systems or small angle ramifications. They report no significant complication such as perforation or excessive bleeding which required additional therapeutic interventions.

Interventional Sialendoscopy

At least 70% of submandibular gland excisions are indicated and performed for chronic inflammations associated with sialadenitis. This operation is not without significant patient risks, haemorrhage, or paralysis of neighbouring nerves – lingual, hypoglossal and the marginal branch of the facial nerve. During the 90’s the use of external Lithotripsy was developed, in an attempt to identify a more simple treatment for salivary stones. Unfortunately, this method does not allow for the removal of all stones that are encountered or present. With the use of sialendoscopy it is now possible to make the diagnosis of stone retained within the salivary ductal system but also to remove these stones when identified, using the same procedure.

Concerments up to 3 mm in the parotid and 4 mm in the submandibular gland can be extracted using endoscopic control with the use of a metallic wire basket procedure. The stones bigger in diameter (approx 10% in the last series) are destroyed or fragmented by the use of a laser, and then extracted (Fig 6). All of
these procedures or operations are performed using the same techniques at the same patients visit. In the series of F. Marchal and colleagues, the need for a general anaesthetic was necessary in 24% of cases. In more than 50% of cases there was identified more than one stone, within the salivary ductal system which was
causing patients symptoms.

Of 45 stones identified within the parotid ductal system, two patients had to be treated by conventional parotidectomy, and only five of 110 patients with stones in the submandibular glands required their gland to be removed as treatment. All of the other patients had their stones removed by the techniques of sialendoscopy, but more than 50% required more than one procedure to achieve all stones to be extracted.

Comment

The use of endoscopes in otology, laryngology and rhinology and the performance of microsurgical procedures are common place in ENT practice for decades, now with the introduce of endoscopy for salivary glands has allowed for clinicians to consider the possibly to increasing their ability to improve quality care for their patients who resent with salivary gland symptoms and disorders.

There is no doubt that diagnostic and interventional sialendoscopy of salivary glands will soon be included in the repertoire of all clinicians and be considered as a standard of practice within a short period of time.

Markus WOLFENSBERGER
President of the Swiss Society of ORL, Head and Neck Surgery
Head, Dept of Head and Neck Surgery, University Hospital Basel, Switzerland

References
1. Marchal F, Dulguerov P, Becker M, Barki G, Disant F, Lehmann W. Specificity of parotid sialendoscopy. Laryngoscope 2001; 111 : 264-71.

2. Marchal F, Dulguerov P, Becker M, Barki G, Disant F, Lehmann W. Submandibular diagnostic and interventional sialendoscopy : new procedure for ductal disorders. Ann Otol Rhinol Laryngol 2002; 111 : 27-35.

3. Marchal F, Dulguerov P. Sialolithiasis management : the state of the art. Arch Otolaryngol Head Neck Surg 2003; 129 : 951-6.