Introduction
The widespread adoption of sialendoscopy is largely due to successful management of patient symptoms (~70–80%) and gland preservation (~95%) that avoids the potential serious complications of gland extirpation. This chapter focuses on complications of sialendoscopy for salivary stones (complications of stenosis [scar] are covered in Chapter 31 ).
Stone-Related Complications
The complications of sialendoscopy can be divided into disease-specific complications related to the underlying pathology (stones) and procedure complications.
Misdiagnosis
Glandular calcifications of any variety are often interpreted as stones by both referring practitioners and radiologists ( Fig. 26.1 ). This is due to the frequent occurrence of parenchymal soft tissue calcifications that result from chronic glandular inflammation. Factors that suggest glandular calcifications that are not stones include nonobstructive symptoms (i.e., swelling not predicated on eating); multigland involvement; multiple, small (1–2 mm) calcifications; and peripheral (intraglandular) location not within central ductal branching pattern. In most cases, patients with the above presentations have chronic inflammatory disorders (e.g., Sjögren; sarcoid; IgG4-related disorders; juvenile recurrent parotitis; idiopathic chronic sialadenitis). Although many of these patients may eventually benefit from sialendoscopy, the goal of the surgery would be to dilate the ducts, flush out inflammatory debris, infuse steroids, and potentially establish a diagnosis via open biopsy of the gland. In such cases, the procedure is expected to reduce symptoms with the recognition that the patient has an ongoing disorder, which will require additional follow-up.
Mistiming
Mistiming of intervention primarily arises from treatment of asymptomatic stones, i.e., the presence of a salivary stone on dental radiography. Gland-preserving salivary surgery exposes the patient to inherent risks and may make an asymptomatic patient symptomatic. In such cases, it is best to educate the patient about the signs and symptoms of glandular obstruction; the need to increase hydration; reduce caffeine; and avoid drying medications and tobacco products. Should symptoms develop, the patient can be offered surgery. Surgery should be postponed until the infection is cleared ( Fig. 26.2 ). Sialendoscopy during acute infection risks converting an acute sialadenitis to a deep neck infection, should a perforation occur.
Missed or Retained Stone
The surgeon should be confident that a given stone is amenable to gland-preserving approaches. Submandibular stones that are not palpable in the floor of the mouth, or located beyond the hilum within the gland below the mylohyoid line, often cannot be retrieved through the mouth and are better served by submandibular gland removal ( Fig. 26.3 ). Accurate determination of the number of stones and their location can be achieved with either a preoperative computed tomography (CT) scan or ultrasonography, although CT is more sensitive for visualizing stones ≤2 mm. Intraoperative ultrasonography is valuable to ensure that the stone(s) is still present and has not moved or spontaneously extruded since the preoperative evaluation. When performing endoscopy alone or with open approaches for stone removal, it is necessary to survey the ductal system before concluding the case, in order to flush out residual debris and check for stone fragments.
Mistaken Anatomy
Mistaken anatomy is the rare but potential pitfall of missing a stone or other pathology when the scope is passed into the wrong duct. Approximately 5–10% of the time, a large Bartholin’s duct from the sublingual gland enters close to the papilla of Wharton’s duct, thereby causing false cannulation of Bartholin’s duct ( Fig. 26.4 ). Indications of this include a short segment duct of small caliber with no visible hilar branching; a deep angle of trajectory into the floor of mouth; and failure to see the expected pathology. If this occurs, the surgeon can slowly withdraw the scope while applying pulse irrigation to identify the take-off of Wharton’s duct. If this take-off cannot be seen or cannulated, the surgeon can perform an open distal dochotomy of Wharton’s duct in order to provide appropriate scope access.
