INTRODUCTION
Salivary duct stenosis is the second most common (15 to 50%) cause of
chronic obstructive sialadenitis following
sialolithiasis.1 It is associated with chronic
inflammatory changes induced by allergy, stones, post-retrieval of
stones, trauma, autoimmune, and radioiodine
therapy.2,3 These conditions often lead to reduced
salivary flow, ascending duct infection, and formation of mucous or
fibrous plaques and stricture in salivary gland
ducts.4 Patients with salivary duct stenosis typically
present with recurrent swelling, pain, or discomfort of the affected
glands that is frequently aggravated during or between
meals.5
Salivary duct stenosis commonly involves the parotid glands (67 to
75%).6 Sialendoscopy allows direct examination of the
tissue characteristics of stenotic lesions in the parotid ducts. Kochet al . described three types of stenosis as follows: inflammatory
(type 1), web-like or circular (type 2), and fibrotic or diffuse (type
3) luminal narrowing.7,8 Type 1 appears to be a
precursor of type 3 stenosis, showing a progressive diffuse narrowing in
the segmental or entire duct.7 In contrast, type 2
stenosis typically tends to form a focal stricture accompanied by a
megaduct with a thin wall due to dilation secondary to mechanical
obstruction. Patients with type 2 stenosis often feel their cheek
swelling while eating, owing to the pooling of saliva in the
reservoir-like megaduct. The stenotic duct can also be classified into
grade 1 (swollen but minimal narrowing), grade 2 (luminal narrowing
< 50%), and grade 3 (luminal narrowing ≥ 50%) according to
the luminal narrowing severity based on sialendoscopic
visualization.9 The stenotic lesions of type 2
stenosis accompanied by a megaduct commonly show higher grades of
narrowing, while types 1 and 3 exhibit varying grades of
stenosis.7,10
Dilation of the stenotic duct is the primary treatment goal for
relieving patients from obstructive symptoms, although conservative care
with sialagogue and gland massage sometimes benefit patients with
chronic obstructive sialadenitis caused by autoimmune or radioiodine
therapy.11,12 The sialendoscopic approach is safe and
effective for treating patients with salivary duct stenosis, with
satisfactory clinical outcomes for relieving
symptoms.4,13,14 However, resolving the stenotic ducts
remains a surgical challenge when sialendoscopy fails to dilate the
stenotic lesions mechanically. The so-called transoral (pull-through)
sialodochoplasty, a surgical technique to remove the stenotic portion of
an involved duct and connect the remaining duct to the buccal mucosa,
has been described in several reports.15-17 However,
the efficacy of transoral sialodochoplasty has not yet been
investigated. This study aimed to analyze the surgical outcomes of
sialendoscopy combined with transoral sialodochoplasty through the
evaluation of changes in obstructive symptoms, characteristics in the
stenotic lesion with a megaduct, and excretory salivary flow of patients
with type 2 stenosis in parotid glands.