Computed tomographic findings in two dogs with chronic unilateral parotid duct ectasia

Abstract

Two dogs were evaluated because of a recurrent left‐sided facial swelling. In Case 1, computed tomography (CT) demonstrated a tubular fluid‐filled mass associated with the left parotid salivary gland and extending to the oral region. On oral examination, no parotid duct papilla was identified, raising the suspicion of an obstruction at the level of the papilla itself, causing secondary ectasia of the duct. Marsupialisation of the duct was performed, but the swelling did not completely reduce. In Case 2, CT revealed a spherical fluid‐filled mass, intimately associated with the left parotid gland and extending cranially. On oral examination, an extension from the mass could be followed rostrally to the level of the oral mucosa, caudal to the maxillary fourth premolar, but the papilla was not visible. No surgery was performed. According to our review of literature, this report represents the first description of CT findings for parotid duct ectasia.

Clinical findings, surgical treatment and outcome in dogs with parotid duct ectasia: 14 cases (2010‐2023)

“…Examination of the parotid papilla was helpful in diagnosing parotid duct ectasia as the majority of the dogs reported in this study had an abnormal parotid papilla. Previous literature reports similar findings (Ladlow & Gregory, 2003; Strøm et al ., 2016); however, in one case report the parotid papilla was not identified (Mestrinho et al ., 2014) or not reported (Tirillini et al ., 2022; Trumpatori et al ., 2007).…”

“…Abnormalities of the parotid salivary gland are uncommon in small animals, when compared with the sublingual and mandibular salivary glands. Parotid gland pathology usually affects the gland itself rather than the duct (Han et al ., 2020; Ladlow & Gregory, 2003; Tirillini et al ., 2022). In a study investigating salivary gland biopsies with pathological changes, the parotid gland represented only 6% of the cases (Lieske & Rissi, 2020).…”

“…In dogs, parotid duct ectasia has been reported secondary to traumatic injuries, sialolith or inflammation (Jeffreys et al ., 1996; Ladlow & Gregory, 2003; Trumpatori et al ., 2007). Other less common causes include parotid duct stenosis after the removal of parotid sialoliths (Han et al ., 2020; Tirillini et al ., 2022), transposed parotid duct ligation (Guinan et al ., 2007), foreign body (Bell, 1978; Goldsworthy et al ., 2013), secondary to maxillectomy surgery (Mestrinho et al ., 2014; Muir & Rosin, 1995), fourth premolar abscess (Harvey, 1969) or obstruction of unknown origin (Tirillini et al ., 2022).…”

“…Human patients affected by parotid duct ectasia present with aesthetic concerns due to a tubular‐shaped swelling in the cheek, inflammatory episodes with mild pain or a purulent fluid present in the oral cavity (Le Roux et al ., 2019). Similarly, the veterinary literature reports dogs presented for a lateralised fluctuant asymptomatic facial swelling over the parotid gland‐duct (Baurmash, 2007; Bell, 1978; Goldsworthy et al ., 2013; Guinan et al ., 2007; Han et al ., 2020; Jeffreys et al ., 1996; Ladlow & Gregory, 2003; Mestrinho et al ., 2014; Muir & Rosin, 1995; Tirillini et al ., 2022; Trumpatori et al ., 2007).…”

“…Minimally invasive techniques including intraductal injections of botulinum toxin A (BTX‐A), balloon dilation and endoscopic sialodochoplasty have also been described (Drage et al ., 2002; Le Roux et al ., 2019; Nahlieli et al ., 2006). In veterinary medicine, similar treatment options have been described including parotidectomy, parotid duct ligation, parotid duct reimplantation, surgical exploration and duct incision and intraoral marsupialisation (Guinan et al ., 2007; Han et al ., 2020; Ladlow & Gregory, 2003; Tirillini et al ., 2022; Yoon et al ., 2017). No information for more conservative options in dogs are currently available.…”