Incidence of different causes of benign obstruction of the salivary glands: retrospective analysis of 493 cases using fluoroscopy and digital subtraction sialography

Success rate of sialendoscopy. A systematic review and meta-analysis

OBJECTIVE

To perform a systematic review and meta-analysis on the efficacy and safety of sialendoscopy in the treatment of obstructive diseases of the major salivary glands.

MATERIALS AND METHODS

We searched four databases for literature. The primary outcome assessed was the success rate. Secondary outcomes included the use of supportive devices, number of sialadenectomies and complications. Risk of bias was assessed. Meta-analyses with subgroup analysis were performed.

RESULTS

In total, 91 studies were included, comprising 8218 patients undergoing 9043 sialendoscopic procedures. The majority of studies had a medium or high risk of bias. The incidence of sialadenectomy varied from 0% to 14%. No major complications were reported. Meta-analysis revealed a weighted pooled success rate of 80.9%. Subgroup analyses showed the weighted pooled success rate in patients with sialoliths (89.6%), stenoses (56.3%), submandibular glands (88.3%), parotid glands (81.2%), patients treated by an endoscopic-assisted transoral removal of a sialolith (86.3%), patients treated by a combined approach of the parotid gland (78.2%), patients with JRP (67.0%) and with RAIS (45.8%).

CONCLUSION

The success rate of sialendoscopy did not considerably change in the last 9 years. Sialendoscopy is an efficient and safe procedure for the treatment of major salivary gland obstructive disease.

Confirmation of eosinophilic sialodochitis by terminal duct biopsy

OBJECTIVE

To analyse the histopathological features of eosinophilic sialodochitis by using terminal duct biopsy.

METHODS

Sixty-five patients with suspected eosinophilic sialodochitis and four with chronic obstructive sialadenitis were prospectively enrolled. Clinical features, laboratory tests and sialograms were comparatively analysed. Terminal duct biopsy of the parotid or submandibular glands was performed concomitantly with endoscopy-assisted duct dilatation to determine the histopathological features of eosinophilic sialodochitis.

RESULTS

Based on eosinophil quantification, the samples of suspected patients were scored as 'definite', 'highly suspected' and 'negative' in 26 (40%), 15 (23.1%) and 24 (36.9%) cases, respectively. Gland types and peripheral blood eosinophil counts were significantly different among these three groups. The proportions of itching glands, mucus plug exudations and elevated immunoglobulin E levels were higher in the 'definite' group than in the other two groups; however, the intergroup differences were insignificant. The primary pathological features of eosinophilic sialodochitis were abundant eosinophils and lymphocytes infiltrated around the duct, degranulation of eosinophils, extensive fibrosis and scattered mastocytes. Periductal eosinophils were not found in cases of chronic obstructive sialadenitis.

CONCLUSION

Our findings suggest that terminal duct biopsy is safe and valuable for the pathological confirmation of eosinophilic sialodochitis, and can be used simultaneously with endoscopy-assisted duct dilatation.

Stensen's Duct Stenosis Balloon Dilatation: Long-term Evaluation of Clinical Outcomes and Quality of Life Impacts

OBJECTIVE

To conduct a long-term retrospective evaluation of the safety and effectiveness of sialographic balloon dilatation in Stensen's duct stenosis (SDS).

STUDY DESIGN

Retrospective cohort.

SETTING

Single-institution academic tertiary referral center.

METHODS

All SDS balloon dilatations (SSBDs) performed from 2011 to 2017 were monitored. Pain relief was evaluated by a numeric rating scale at 3-year follow-up at least. Long-term glandular swelling frequency patterns, quality of life (QoL), and drug consumption were retrospectively assessed. Procedure-related complications were recorded.

RESULTS

Twenty-one SSBD procedures were recorded (mean ± SD age, 55 ± 12 years), all performed under local anesthesia. SSBD led to complete dilatation in 7 patients (33%), residual stenosis in 8 (38%), and no dilatation (failure) in 6 (29%). Retrospective analysis of clinical outcomes was possible for 17 patients, 71% of whom presented with long-term pain relief, at a mean relief of 3.2 points on the numeric rating scale (P < .001). Long after SSBD, patients presented with a mean decrease of 15.4 glandular swellings per month (P < .001). Medical consumption was reduced to 18% of patients taking some drugs because of SDS after SSBD vs 71% before. SSBD showed an impact on QoL in >80% of patients, with mean improvements of 26% and 25% in the percentage point reduction of physical and mental QoL, respectively (P < .001). No complications were noted except temporary discomfort due to the procedure.

CONCLUSION

Despite the advent of sialendoscopy-guided techniques, SSBD should be considered for SDS treatment, as it is a safe procedure and provides sustained pain relief.

Proteomic analysis of sialoliths from calcified, lipid and mixed groups as a source of potential biomarkers of deposit formation in the salivary glands

Salivary stones, also known as sialoliths, are formed in a pathological situation in the salivary glands. So far, neither the mechanism of their formation nor the factors predisposing to their formation are known despite several hypotheses. While they do not directly threaten human life, they significantly deteriorate the patient's quality of life. Although this is not a typical research material, attempts are made to apply various analytical tools to characterise sialoliths and search for the biomarkers in their proteomes. In this work, we used mass spectrometry and SWATH-MS qualitative and quantitative analysis to investigate the composition and select proteins that may contribute to solid deposits in the salivary glands. Twenty sialoliths, previously characterized spectroscopically and divided into the following groups: calcified (CAL), lipid (LIP) and mixed (MIX), were used for the study. Proteins unique for each of the groups were found, including: for the CAL group among them, e.g. proteins from the S100 group (S100 A8/A12 and P), mucin 7 (MUC7), keratins (KRT1/2/4/5/13), elastase (ELANE) or stomatin (STOM); proteins for the LIP group-transthyretin (TTR), lactotransferrin (LTF), matrix Gla protein (MPG), submandibular gland androgen-regulated protein 3 (SMR3A); mixed stones had the fewest unique proteins. Bacterial proteins present in sialoliths have also been identified. The analysis of the results indicates the possible role of bacterial infections, disturbances in calcium metabolism and neutrophil extracellular traps (NETs) in the formation of sialoliths.

An Updated Patient-Centered Sialadenitis Instrument: The Obstructive Salivary Problem Impact Test (SPIT)

OBJECTIVE

The Chronic Obstructive Sialadenitis Symptoms questionnaire (COSS) was created to assess chronic sialadenitis symptoms and treatment response, but its development lacked patient input and validation. We analyzed COSS responses and feedback from sialadenitis patients and physician experts to create the novel obstructive Salivary Problem Impact Test (SPIT), a new standardized measure of sialadenitis-associated symptoms.

METHODS

We analyzed COSS responses via exploratory factor analysis (EFA) to identify essential symptom domains and reduce overlap in questions. Sialadenitis patients evaluated the significance of index symptoms identified from the literature review. Expert physicians rated symptom relevance in clinical assessment. An updated questionnaire (SPIT) was piloted with both patient and expert interviews to optimize structure and readability. The SPIT was assessed for internal consistency, construct validity, and test-retest stability.

RESULTS

EFA of 310 COSS responses demonstrated 3 main symptom domains (functional impact, pain, swelling) that explained 58.4% of response variance. Results were not statistically different when collapsing from 11 to 5 question response options. Experts (n = 5) ranked gland swelling, mealtime pain, and foul taste as most clinically important, while patients (n = 12) ranked swelling, non-mealtime pain, and difficulty eating as most bothersome. Most patients experienced sialadenitis-related functional or psychosocial impairment. Following interviews for question refinement, a 25-question survey was finalized. SPIT responses from 50 sialadenitis patients demonstrated internal consistency (Cronbach's alpha = 0.96), 14-day stability (p < 0.001), and agreement with Oral Health Impact Profile-14 scores (p < 0.0001).

CONCLUSIONS

We developed the SPIT instrument to improve usability and content validity in chronic sialadenitis evaluation. The psychometric assessment demonstrated high construct validity and test-retest reliability. Further work will assess longitudinal changes with treatment.

LEVEL OF EVIDENCE

4 Laryngoscope, 133:539-546, 2023.

Intraductal Fragmentation in Sialolithiasis Using Pneumatic Lithotripsy: Initial Experience and Results

OBJECTIVE

To report initial experience in using a pneumatic lithotripter to treat salivary stones.

STUDY DESIGN

Level IV retrospective study.

SETTING

University hospital and tertiary referral center.

METHODS

A pneumatic lithotripter was used to treat salivary stones after these were diagnosed. Probes with diameters of 0.7 mm were used. Total fragmentation was intended in all stones. Stone fragments were removed using several instruments in serial sialendoscopies to achieve complete stone clearance.

RESULTS

A total of 62 patients with 77 stones were treated. Forty-three submandibular stones were treated in 34 patients, and 34 parotid stones were treated in 28 patients. An operating pressure of 2.5 bar and a single frequency mode were used. Complete fragmentation was achieved in all but one of the treated stones in both glands (98.7%). Among the patients, 90.32% became stone free and 100% symptom free. Multiple stones were treated in 24.19% of the patients, and multimodal therapy was also carried out in 24.19%. All of the glands were preserved.

CONCLUSIONS

The pneumatic lithotripter proved to be effective in the treatment of sialolithiasis. Stone size, location, and the gland involved were important clinical factors. The device was sufficient to achieve success without any increased risk for complications in the patients or damage to the sialendoscopes.

[Updated S2k AWMF guideline on obstructive sialadenitis]

The update of this guideline was an important step to define standards for the use of sialendoscopy and other emerging minimally invasive techniques for the therapy of sialolithiasis and other obstructive salivary gland diseases. The current actualization was necessary to adapt the diagnostic and therapeutic algorithms to the current scientific knowledge. In this article they are presented in a shortened version with a focus on conservative therapeutic measures which are especially relevant for daily practice.

Incorporating Sialendoscopy into the Otolaryngology Clinic

Simple sialendoscopy procedures may be performed in the outpatient clinic with few complications. This process spares patients the risks, increased cost, and time burdens of sialendoscopy under general anesthesia. Sialendoscopy procedures may be incorporated into the outpatient practice after gaining experience with these procedures in the operating room. Diagnostic sialendoscopy, dilation of stenosis, and endoscopic sialolithotomies of small, freely mobile stones are appropriate for in-office sialendoscopy in many instances.

Allergy-Related Sialodochitis: A Preliminary Cohort Study

OBJECTIVES/HYPOTHESIS

To explore the clinically feasible diagnosis criteria and treatment outcomes of allergy-related sialodochitis (ARS).

STUDY DESIGN

Prospective Cohort Study.

METHODS

Ninety-six consecutive patients were enrolled by the following criteria: 1) recurrent swelling of ≥2 large salivary glands that lasted for ≥3 months; 2) with mucus plug exudations; 3) with atopic diseases; 4) ductal stenosis and/or ectasia. Sixty-four patients with elevation of peripheral blood eosinophil (PBE) and/or serum IgE level comprised group A (highly-suspected ARS group), while the remaining 32 comprised group B (patients without confirmed evidence of ARS). These patients were treated with interventional endoscopy. A chronic obstructive sialadenitis symptom (COSS) questionnaire was used to quantify the treatment outcomes.

RESULTS

In group A, Serum IgE was elevated in 84.4% of patients and PBE was elevated in 34.4% of patients. Percentage of submandibular gland involvement was higher in group A than group B (48.4% vs. 18.8%). On sialograms, the snowflake changes of branch ducts were seen in higher percentage of group A compared with group B (59% vs. 35% for parotid glands, 27% vs. 8% for submandibular glands, respectively). Mucus plug smears showed abundant eosinophils in 14 group A patients. Biopsy of five group A patients revealed significant eosinophil infiltration around the main and interlobular ducts. During follow-up, the COSS scores were significantly decreased in both groups, and group B was improved better than group A.

CONCLUSION

PBE and serum IgE are important diagnostic indexes of ARS. Mucus plug smear or histopathology verifies the diagnosis. Interventional endoscopy is helpful for ARS cases.

LEVEL OF EVIDENCE

3 Laryngoscope, 131:2030-2035, 2021.

Neutrophil Extracellular Traps Promote the Development and Growth of Human Salivary Stones

Salivary gland stones, or sialoliths, are the most common cause of the obstruction of salivary glands. The mechanism behind the formation of sialoliths has been elusive. Symptomatic sialolithiasis has a prevalence of 0.45% in the general population, is characterized by recurrent painful periprandial swelling of the affected gland, and often results in sialadenitis with the need for surgical intervention. Here, we show by the use of immunohistochemistry, immunofluorescence, computed tomography (CT) scans and reconstructions, special dye techniques, bacterial genotyping, and enzyme activity analyses that neutrophil extracellular traps (NETs) initiate the formation and growth of sialoliths in humans. The deposition of neutrophil granulocyte extracellular DNA around small crystals results in the dense aggregation of the latter, and the subsequent mineralization creates alternating layers of dense mineral, which are predominantly calcium salt deposits and DNA. The further agglomeration and appositional growth of these structures promotes the development of macroscopic sialoliths that finally occlude the efferent ducts of the salivary glands, causing clinical symptoms and salivary gland dysfunction. These findings provide an entirely novel insight into the mechanism of sialolithogenesis, in which an immune system-mediated response essentially participates in the physicochemical process of concrement formation and growth.

Eosinophilic Sialodochitis: A Type of Chronic Obstructive Sialadenitis Related to Allergy

OBJECTIVES

To investigate the clinical, laboratory, radiological, histopathological, and immunohistochemical features, and the expression of allergy-related cytokines in eosinophilic sialodochitis (ES).

METHODS

Thirty-eight patients diagnosed with chronic obstructive sialadenitis (COS) who had undergone glandular excision or incisional biopsy were enrolled. Seventeen patients with comorbid atopic disease and increased ductal tissue eosinophils comprised the ES group, while 21 patients comprised the COS group. The clinicopathological features and allergy-related cytokine expression were compared between groups.

RESULTS

The ES group frequently involved multiple, bilateral major salivary glands, and the number of glands was significantly greater than the COS group (2.8 ± 1.1 vs. 1.2 ± 0.4, P < .001). Serum immunoglobulin (Ig) E was elevated in 91% of patients in ES group (419 ± 357 kU/L) and peripheral blood eosinophil was significantly greater compared with the COS group (7.6% ± 4.6% vs. 2.5% ± 1.4%, P < .001). Histologically, eosinophil infiltration in ES group was observed around the main and interlobular ducts (50 ± 39/high power field [HPF]). Follicular hyperplasia (76%), epithelial mucous metaplasia (82%), and mucus plugs with eosinophils (41%) were observed. IgE-positive cell count was 20.7 ± 18.3/HPF and tryptase-positive mast cell count was 23.5 ± 15.1/HPF, which was significantly greater than the respective cell counts in COS group, which mainly infiltrated around the ducts. The levels of interleukin-4, interleukin-13, and eotaxin in tissue were significantly greater in ES than the COS group.

CONCLUSIONS

The clinicopathological characteristics of ES are significantly different from COS and ES might have an allergy-related pathogenesis.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:E800-E806, 2021.

[Acute infectious disease of otolaryngology focus]

Infections are the most common cause of antibiotic prescription and one of the most frequent reasons for consultation in Primary Care. Among them, stand out acute media otitis and diffuse external otitis, acute pharyngitis and acute rhinosinusitis. Commonly they are viral and self-limited, so their complications are rare. Currently, the indiscriminate use of antibiotics have leaded to bacterial resistances; therefore antibiotic prescription should be more careful. Nowadays, several diagnostic strategies are available. In current updated etiological and pathophysiological factors of each infection, diagnostic and therapeutic strategy to be applied in Primary Care as well as the complications of each pathology and the referral indications to be assessed by specialists in the ENT area, will be reviewed.

Salivary duct stenosis: diagnosis and treatment

The management of stenoses of the major salivary glands had undergone a significant change during the last 15-20 years. Accurate diagnosis forms the basis of adapted minimal invasive therapy. Conventional sialography and MR-sialography are useful examination tools, and ultrasound seems to be a first-line investigational tool if salivary duct stenosis is suspected as cause of gland obstruction. Sialendoscopy is the best choice to establish final diagnosis and characterise the stenosis in order to plan accurate treatment. In all major salivary glands, inflammatory stenosis can be distinguished from fibrotic stenosis. In the parotid duct system, an additional stenosis associated with various abnormalities of the duct system has been reported. Conservative therapy is not sufficient in the majority of cases. The development of a minimally invasive treatment regime, in which sialendoscopy plays a major role, has made the preservation of the gland and its function possible in over 90% of cases. Ductal incision procedures are the most important measure in submandibular duct stenoses, but sialendoscopy becomes more important in the more centrally located stenoses. Sialendoscopic controlled opening and dilation is the dominating method in parotid duct stenoses. In 10-15% of cases, success can be achieved after a combined treatment regime had been applied. This review article aims to give an overview on the epidemiology, diagnostics and current state of the art of the treatment of salivary duct stenoses.

Radiocontrast Dye Extravasation During Sialography

Objective:

Evaluate the pathophysiology of contrast extravasation.

Methods:

Two hundred fifty-five sialograms at the University of Iowa from 2008 to 2016 were reviewed.

Results:

Twelve sialograms (4.7% of total) were identified with main ductal extravasation. In each case, ductal stenosis as a diagnosis was supported by clinical history and the finding of difficulty in advancing the cannula into the duct during sialography. In all but 1 case, extravasation occurred at the distal duct with no further imaging of the ductal system. Each of the 5 cases treated with sialendoscopy with or without gland resection confirmed stenosis. Ultrasound evaluation of 5 of the cases detected ductal dilation in 4 (80%). Six of 11 computed tomography scans done before the sialogram were interpreted as normal with indirect evidence for ductal stenosis (duct dilation) reported in only 1. All extravasations were associated with either stricture alone or stricture with stone (1 case).

Conclusion:

Radiocontrast extravasation from the main duct during sialography is highly associated with the presence of ductal stricture. In our experience, the inability to fill the ductal system with radiocontrast is a useful sialographic finding that correlated closely with anatomic abnormality rather than technical error. The frequent finding of extravasation of radiocontrast supports the use of water soluble contrast.

Is there a role for ultrasound-guided balloon sialoplasty technique in salivary gland structures

Ductal stricture is a common cause of obstructive salivary gland disease. Balloon dilatation of the parotid duct as a minimally invasive technique is currently carried out under fluoroscopic guidance or during sialendocopy. We present a case report of ultrasound-guided balloon dilatation. A 45-year-old female presented with a long history of obstructive symptoms affecting the right parotid gland. Ultrasound examination revealed a tortuous right main parotid duct with marked dilatation throughout its course and multiple sites of focal stricture formation. A sialogram was carried out to further characterize the ductal system, it showed significant dilatation of the main duct but due to overlapping of the elements of sialodochitis the visualization of the location and presence of strictures was very difficult. It was felt that ultrasound would be a better imaging modality to utilize in order to guide balloon dilatation of the strictures. Therefore, a balloon dilatation was carried out under ultrasound guidance. The main advantage of this technique is to preserve the physician and the patient from radiation exposure. In our knowledge this is the first case reported yet in the literature.