Operative Techniques With Diagnostic Sialendoscopy

Introduction

Diagnostic sialendoscopy is fundamental in the assessment and the treatment of salivary gland ductal pathology. Because of this diagnostic modality, the main duct, secondary, and tertiary branches can practically all be explored and evaluated. Diagnostic sialendoscopy can either be done as a single procedure or it can be incorporated in a more complex surgery involving combined or purely endoscopic approaches.

Diagnostic sialendoscopy must not be viewed as a minor part of a surgery performed only at the beginning of these combined or purely endoscopic procedures. It is a dynamic tool during the different parts of the surgery. For example, after removing a submandibular hilar stone transorally, it is paramount to proceed with a proximal endoscopy to evaluate for residual stones or stenosis that need to be addressed.

The purpose of this chapter is to: (1) help distinguish the gross and subtle differences between inflammatory salivary gland disorders evaluated with diagnostic sialendoscopy; (2) offer technical maneuvers to improve the chances of correct diagnosis; and (3) assess and predict the chances of success of interventional sialendoscopy.

Choosing the Appropriate Endoscope for Diagnostic Sialendoscopy

All sialendoscopes can adequately perform diagnostic sialendoscopy. It is important to understand the advantages and disadvantages of each endoscope. Endoscopes are roughly divided into two categories: the all-in-one system (Marchal and Erlangen sets, Karl Storz, Tuttlingen, Germany) and the modular system (Marchal Modular set, Karl Storz). The former has integrated rinsing and operating channels (the operating channel is absent in the endoscopes that have a diameter <1 mm). The latter consists of a nude optic fiber (0.75 or 1 mm in diameter), which is inserted into an examination or operating sheaths. The examination sheath only has a rinsing channel, whereas the operating sheaths have an additional operating channel.

For purely diagnostic sialendoscopy, surgeons prefer to start with the smallest endoscopes. The obvious advantage of smaller endoscopes is that they can easily be inserted inside the duct once the papilla has been dilated. In addition, they can navigate through smaller ductal branches and stenosis with more ease. There are basically seven endoscopes that can be used at the start of a case: the 0.8 mm and 1.1 mm (Erlangen all-in-one set), the 0.89 mm, 1.1 mm and 1.3 mm (Marchal all-in-one set) and the 0.75 mm and 1 mm modular endoscopes with their corresponding examination sheaths. The 0.75 mm and 1 mm modular endoscopes are traditionally used in the parotid and submandibular glands, respectively. The main advantage of the 1.1 mm and 1.3 mm endoscopes is that a guidewire can be inserted through the operating channel. The guidewire can only be inserted through the operating channel of the operative sheaths of the modular endoscope. The choice of the endoscope ultimately depends on the preference and experience of the surgeon.

Diagnostic Evaluation of the Salivary Gland Ductal System

The purpose of diagnostic sialendoscopy is to characterize, as much as possible, the cause of the ductal obstruction. The endoscopic findings can be divided in three categories: sialolithiasis, stenosis, and inflammatory. The first two are causal obstructive factors, and the third one, an epiphenomenon. One should keep in mind that the endoscopic findings during diagnostic sialendoscopy are important clues that lead the surgeon to decide what is the best surgical approach.