Sialendoscope-assisted transoral removal of hilo-parenchymal sub-mandibular stones: surgical results and subjective scores

Intraoral Microscopic Versus Robot-Assisted Sialolithotomy and Sialendoscopy for Submandibular Stones

OBJECTIVE

Sialendoscopy has remained the standard of treatment for sialolithiasis; however, large stones impacted in the submandibular gland hilum often require an intra-oral combined approach.

METHODS

Patients treated for submandibular hilar sialolithiasis from 2015 to 2021 at two tertiary centers were stratified into two groups based on the surgical technique: Intraoral Microscopic-Assisted Sialolithotomy (IMAS) versus Robot-Assisted Sialolithotomy and Sialendoscopy (RASS). We compared the characteristics of retrieved stones, surgical success rate, operative time, and post-operative complications in both techniques. True surgical success was defined as successful stone extraction without reoccurrence within 12 months.

RESULTS

The RASS technique was attempted in 60 patients and successful in 56 (93.3%) cases whereas the IMAS technique was performed in 52 patients and successful in 48 (92.3%) cases. The longest dimension of the predominant retrieved calculi was 9.6 ± 3.1 mm (range, 5-18 mm) for the robotic technique and 10 ± 4.8 mm (range, 5-30 mm) for the microscopic technique. The operative time for the robotic technique excluding robot setup time was 70.6 ± 24.8 min compared to 61.9 ± 42.4 min for microscopic technique (p = 0.018). No major adverse outcomes were reported; however, temporary lingual paresthesia was found in ten robotic (16.7%) and five microscopic (9.6%) cases.

CONCLUSION

The two techniques were comparable in terms of efficacy and safety for large stones. The robot has the advantage of intraoral high dynamic maneuverability and improved surgeon posture while the microscopic technique has the advantage of intraoral tactile feedback. The procedure was significantly shorter in duration with the microscope.

LEVEL OF EVIDENCE

3 Laryngoscope, 134:2170-2176, 2024.

Removal of intraglandular calculi in Wharton's duct: clinical outcome and treatment algorithm

The aim of this study was to propose a treatment strategy for intraglandular submandibular calculi based on calculus site. Seventy-three consecutive patients with impalpable intraglandular submandibular calculi were enrolled retrospectively. The calculi were classified as either post-hilar type, central type, or superficial type. Treatment approaches included transoral duct slitting (TDS), interventional basket retrieval (IBR), intraductal laser lithotripsy (ILL), and transcervical lithotomy (TCL). Complete calculus removal with gland preservation was achieved in 64 patients (87.7%). The success rate for post-hilar, central, and superficial calculi was 86.4% (51/59), 90.9% (10/11), and 100% (3/3), respectively. The treatment approach applied in patients with treatment success was TDS in 32 cases, IBR in 20, ILL in nine, and TCL in three. During follow-up (median 17.3 months), one patient experienced gland atrophy and three had ductal stenosis; the remaining 60 patients (93.8%, 60/64) had good clinical outcomes. In the eight failure cases operated by TDS, the deeply situated calculi could not be detached despite the parenchymal incision in five cases, while the procedure was ceased due to the patient's inability to cooperate in the other three cases. In the remaining failure case, the submandibular gland was sacrificed after calculus extraction via TCL. Application of the proposed treatment algorithm might help preserve gland function in patients with intraglandular submandibular calculi.

[Recent progress in the treatment of intractable sialolithiasis]

Sialolithiasis occurs in approximately 0.45% to 1.20% of the general population. The typical clinical symptom manifests as a painful swelling of the affected glands after a meal or upon salivary stimulation, which extremely affects the life quality of the patients. With the development of sialendoscopy and lithotripsy, most sialoliths can be successfully removed with preservation of the gland. However, sialoliths in the deep hilar-parenchymal submandibular ducts and impacted parotid stones located in the proximal ducts continue to pose great challenges. Our research center for salivary gland diseases (in Peking University School and Hospital of Stomatology) has used sialendoscopy for 17 years and treated >2 000 patients with salivary gland calculi. The success rate was approximately 92% for submandibular gland calculi and 95% for parotid calculi. A variety of minimally invasive surgical techniques have been applied and developed, which add substantial improvements in the treatment of refractory sialolithiasis. Further, the radiographic positioning criteria and treatment strategy are proposed for these intractable stones. Most of the hilar-parenchymal submandibular stones are successfully removed by a transoral approach, including transoral duct slitting and intraductal basket grasping, while a small portion of superficial stones can be removed by a mini-incision in submandibular area. Impacted stones located in the distal third of parotid gland ducts are removed via "peri-ostium incision", which is applied to avoid a cicatricial stenosis from a direct ostium incision. Impacted parotid stones located in the middle and proximal third of the Stensen's duct are removed via a direct mini-incision or a peri-auricular flap. A direct transcutaneous mini-incision is commonly performed under local anesthesia with an imperceptible scar, and is indicated for most of impacted stones located in the middle third, hilum and intraglandular ducts. By contrast, a peri-auricular flap is performed under general anesthesia with relatively larger operational injury of the gland parenchyma, and should be best reserved for deeper intraglandular stones. Laser lithotripsy has been applied in the treatment of sialolithiasis in the past decade, and holmium ∶YAG laser is reported to have the best therapeutic effects. During the past 3 years, our research group has performed laser lithotripsy for a few cases with intractable salivary stones. From our experiences, withdrawal of the endoscopic tip 0.5-1.0 cm away from the extremity of the laser fiber, consistent saline irrigation, and careful monitoring of gland swelling are of vital importance for avoidance of injuries of the ductal wall and the vulnerable endoscope lens during lithotripsy. Larger calculi require multiple treatment procedures. The risk of ductal stenosis can be alleviated by endoscopic dilation. In summary, appropriate use of various endoscopy-assisted lithotomy helps preserve the gland function in most of the patients with refractory sialolithiasis. Further studies are needed in the following aspects: Transcervical removal of intraglandular submandibular stones, intraductal laser lithotripsy of impacted parotid stones and deep submandibular stones, evaluation of long-term postoperative function of the affected gland, et al.

Transoral submandibulotomy plus duct marsupialization; an appropriate approach for the treatment of proximal submandibular sialolithiasis; a long-term follow-up study

BACKGROUND

Sialolithiasis is the most common salivary gland-related disease worldwide, leading to sialadenitis. Although there is no serious problem with surgical removal of stones at the middle and distal parts of the Wharton's duct, the approach for treating proximal stones located near to hilum and its adjacent parenchyma is a challenge. The current study has aimed to evaluate the outcome of transoral submandibulotomy for submandibular gland stone treatment.

METHODS

This study was conducted on 63 patients with proximal (or deep hilar) submandibular sialolithiasis treated with transoral submandibulotomy and duct marsupialization from January 2011 to April 2019 in Pars hospital. Complications of the old fashion surgery (transcervical submandibulectomy) were assessed in this method (number and size of the stone(s), relapse of sialolithiasis-related obstructive symptoms, partial or complete removal of the stone(s), sialolithiasis recurrence, postoperative surgical or nonsurgical intervention, foreign body sensation, and taste sensation quality).

RESULTS

The stone(s) was located at the proximal of the duct in 68% of the cases, while 32% of the stones were located at the deep hilar region. The mean size of the stones was 1.28±0.51 cm. Postoperative inflammation, postoperative pain, sialolithiasis recurrence, obstructive symptoms, postoperative nonsurgical intervention, postoperative surgical intervention, reduced taste sensation, and foreign body sensation were presented in 24%, 29%, 29%, 44%, 14%, 6%, 11%, and 10% respectively. Eighty-nine percent of recurrences were healed spontaneously.

CONCLUSION

Considering the cosmetic advantage due to the lack of cervical surgery scar (which is mandatory in old fashion transcervical method), long-term follow-up of transoral submandibulotomy showed successful outcomes regarding neurological impairment, postoperative pain and inflammation and incredibly complete stone removal that was found in all of the patients. In addition, submandibular duct marsupialization is recommended based on our study.

Contemporary Review of Submandibular Gland Sialolithiasis and Surgical Management Options

One of the most common disorders of the salivary glands is obstructive sialolithiasis. Salivary gland obstruction is important to address, as it can significantly impact patient quality of life and can progress to extensive cellulitis and abscess formation if left untreated. For small and accessible stones, conservative therapies often produce satisfactory outcomes. Operative management should be considered when stones are inaccessible or larger in size, and options include sialendoscopy, laser lithotripsy, extracorporeal shockwave lithotripsy, transoral surgery, and submandibular gland adenectomy. Robotic approaches are also becoming increasingly used for submandibular stone management. The purpose of this review is to summarize the modern-day management of submandibular gland obstructive sialolithiasis with an emphasis on operative treatment modalities. A total of 77 articles were reviewed from PubMed and Embase databases, specifically looking at the pathophysiology, clinical presentation, diagnosis, and management of submandibular sialolithiasis.

Transoral removal of a hilo-parenchymal submandibular sialolith

In sialolithiasis, the lithiasis is often large and located at the junction of the middle and posterior third of the duct, in the hilum region. In such cases, transoral approach for submandibular lithiases (TASL) is a useful treatment of choice in patients with large submandibular stones that can be palpated bimanually.

[Studies on newly recognized chronic sialadenitis]

Some kinds of chronic sialadenitis were recognized during the recent years. They have specific pathogenesis, clinical and histopathologic appearances, and require specific treatment. IgG4-related sialadenitis (IgG4-RS) is one of the immune-mediated diseases, characterized by tumefactive lesions. The incidence of IgG4-RS obviously increased during the past 30 years. The study on the potential relationship between occupational exposure to chemical substances and the incidence of IgG4-RS showed that subjects with occupational exposure to agents known to cause IgG4-RD had an increased risk for IgG4-RS. Surgical excision of involved SMG could not control the disease progression, which is not recommended for treatment of IgG4-RS. The combination of glucocorticoid and steroid-sparing agents is effective for treating IgG4-RS, and restores salivary gland function. Radioiodine induced sialadenitis (RAIS) is one of the common complications of postoperative adjuvant treatment of differentiated thyroid cancer by ¹³¹I. The incidence of the disease is related to radiation dosage. Clinically, the patients suffered from swelling and tenderness in the buccal or submandibular regions, especially during the mealtime. Imaging appearances are similar to those of chronic obstructive sialadenitis. Conservative managements, such as gland massage, sialagogues, are the mainstream methods in the treatment of RAIS. Sialendoscopy is feasible for RAIS, but not as effective as conventional obstructive sialadenitis (COS). Therefore the prevention of RAIS is crucial. Eosinophilic sialodochitis (ES) is a new type of chronic inflammatory disease of the salivary gland related to allergy. It has characteristics of swelling of multiple major salivary glands, strip-like gelatinous plugs discharged from the duct orifice of the gland, elevated level of serum IgE and eosinophils in peripheral blood, infiltration of eosinophils and IgE positive plasma cells in the tissues, allergic history, increased expression of allergy-related cytokines, such as IL-4, IL-5, IL-13, and eotaxin, which suggest allergic reactions as a potential pathogenesis of the disease. The clinical, laboratory, histological, and immunohistochemical characteristics of ES are significantly different from conventional obstructive sialadenitis (COS). Therefore, it is suitable to separate ES from COS. Conservative managements, such as self-maintenance therapy and anti- allergic modality are the choices of treatment for ES. Based on the results of our comprehensive studies a new classification of chronic sialadenitis is suggested.

[Studies on newly recognized chronic sialadenitis]

Some kinds of chronic sialadenitis were recognized during the recent years. They have specific pathogenesis, clinical and histopathologic appearances, and require specific treatment. IgG4-related sialadenitis (IgG4-RS) is one of the immune-mediated diseases, characterized by tumefactive lesions. The incidence of IgG4-RS obviously increased during the past 30 years. The study on the potential relationship between occupational exposure to chemical substances and the incidence of IgG4-RS showed that subjects with occupational exposure to agents known to cause IgG4-RD had an increased risk for IgG4-RS. Surgical excision of involved SMG could not control the disease progression, which is not recommended for treatment of IgG4-RS. The combination of glucocorticoid and steroid-sparing agents is effective for treating IgG4-RS, and restores salivary gland function. Radioiodine induced sialadenitis (RAIS) is one of the common complications of postoperative adjuvant treatment of differentiated thyroid cancer by 131I. The incidence of the disease is related to radiation dosage. Clinically, the patients suffered from swelling and tenderness in the buccal or submandibular regions, especially during the mealtime. Imaging appearances are similar to those of chronic obstructive sialadenitis. Conservative managements, such as gland massage, sialagogues, are the mainstream methods in the treatment of RAIS. Sialendoscopy is feasible for RAIS, but not as effective as conventional obstructive sialadenitis (COS). Therefore the prevention of RAIS is crucial. Eosinophilic sialodochitis (ES) is a new type of chronic inflammatory disease of the salivary gland related to allergy. It has characteristics of swelling of multiple major salivary glands, strip-like gelatinous plugs discharged from the duct orifice of the gland, elevated level of serum IgE and eosinophils in peripheral blood, infiltration of eosinophils and IgE positive plasma cells in the tissues, allergic history, increased expression of allergy-related cytokines, such as IL-4, IL-5, IL-13, and eotaxin, which suggest allergic reactions as a potential pathogenesis of the disease. The clinical, laboratory, histological, and immunohistochemical characteristics of ES are significantly different from conventional obstructive sialadenitis (COS). Therefore, it is suitable to separate ES from COS. Conservative managements, such as self-maintenance therapy and anti- allergic modality are the choices of treatment for ES. Based on the results of our comprehensive studies a new classification of chronic sialadenitis is suggested.

Quality of life after sialendoscopy: prospective non-randomized study

BACKGROUND

The symptomatic (swelling and pain) salivary gland obstructions are caused by sialolithiasis and salivary duct stenosis, negatively affecting quality of life (QOL), with almost all candidates for clinical measures and minimally invasive sialendoscopy. The impact of sialendoscopy treatment on the QOL has been little addressed nowadays. The objective is to prospectively evaluate the impact of sialendoscopy on the quality of life of patients undergoing sialendoscopy due to benign salivary obstructive diseases, measured through QOL questionnaires of xerostomia degree, the oral health impact profile and post sialendoscopy satisfaction questionnaires.

RESULT

37 sialendoscopies were included, most young female; there were 64.5% sialolithiasis and 35.4% post-radioiodine; with 4.5 times/week painful swelling symptoms and 23.5 months symptom duration. The pre- and post-sialendoscopy VAS values were: 7.42 to 1.29 (p < 0.001); 86.5% and 89.2% were subjected to sialendoscopy alone and endoscopic dilatation respectively; 80.6% reported improved symptoms after sialendoscopy in the sialolithiasis clinic (p < 0.001). The physical pain and psychological discomfort domain scores were mostly impacted where sialendoscopy provided relief and improvement (p < 0.001). We found a positive correlation between sialendoscopy and obstructive stone disease (p < 0.001) and no correlation in sialendoscopy satisfaction in xerostomia patients (p = 0.009).

CONCLUSIONS

We found improved symptoms with overall good satisfaction after sialendoscopy correlated with stones; and a negative correlation between xerostomia. Our findings support the evident indication of sialendoscopy for obstructive sialolithiasis with a positive impact on QOL and probably a relative time-dependent indication for stenosis/other xerostomia causes that little improved QOL satisfaction.

LEVEL OF EVIDENCE

2b-Prospective non-randomized study.

TRIAL REGISTRATION

WHO Universal Trial Number (UTN): U1111-1247-7028; Brazilian Clinical Trials Registry (ReBeC): RBR-6p8zfs.

Treatment of Sialolithiasis: What Has Changed? An Update of the Treatment Algorithms and a Review of the Literature

Treatment for sialolithiasis has undergone significant changes since the 1990s. Following the development of new minimally invasive and gland-preserving treatment modalities, a 40-50% rate of gland resection was reduced to less than 5%. Extracorporeal shock-wave lithotripsy (ESWL), refinement and extension of methods of transoral duct surgery (TDS), and in particular diagnostic and interventional sialendoscopy (intSE) are substantial parts of the new treatment regimen. It has also become evident that combining the different treatment modalities further increases the effectiveness of therapy, as has been especially evident with the combined endoscopic-transcutaneous approach. In the wake of these remarkable developments, a treatment algorithm was published in 2009 including all the known relevant therapeutic tools. However, new developments have also taken place during the last 10 years. Intraductal shock-wave lithotripsy (ISWL) has led to remarkable improvements thanks to the introduction of new devices, instruments, materials, and techniques, after earlier applications had not been sufficiently effective. Techniques involving combined approaches have been refined and modified. TDS methods have been modified through the introduction of sialendoscopy-assisted TDS in submandibular stones and a retropapillary approach for distal parotid sialolithiasis. Recent trends have revealed a potential for significant changes in therapeutic strategies for both major salivary glands. For the submandibular gland, ISWL has replaced ESWL and TDS to some extent. For parotid stones, ISWL and modifications of TDS have led to reduced use of ESWL and the combined transcutaneous-sialendoscopic approach. To illustrate these changes, we are here providing an updated treatment algorithm, including tried and tested techniques as well as promising new treatment modalities. Prognostic factors (e.g., the size or location of the stones), which are well recognized as having a strong impact on the prognosis, are taken into account and supplemented by additional factors associated with the new applications (e.g., the visibility or accessibility of the stones relative to the anatomy of the duct system).

Transoral robotic submandibular sialadenectomy: how and when

Traditional removal of the submandibular gland is done through a transcervical approach; new proposals have come into the scientific limelight such as endoscopy-assisted transcervical sialadenectomy or (robot-assisted) submandibular sialadenectomy through a postauricular facelift transcervical approach. Transoral submandibular sialadenectomy has been described in the past, but with the advent of transoral robotic surgery, the proposal of removing the submandibular gland from the oral floor is gaining strength. A transoral robotic submandibular sialadenectomy by the Si Da Vinci Surgical Robot was performed in a 68-years-old female patient under general anaesthesia. The transoral robotic procedure was successful with no major postoperative complications. A mild tingling of the tip of the tongue was described by the patient 3 months after. The surgical time took 110 minutes. No residual gland was observed at ultrasonography. The transoral robotic submandibular sialadenectomy seems to be, with selective indication based on clinical and radiological assessment, a viable and safe alternative to traditional management in patients who refuse a cervical scar and the risk of paralysis of the facial nerve.

3D video-assisted trans-oral removal of deep hilo-parenchymal sub-mandibular stones

The aim of this paper is to describe the intra-operative findings and surgical results of the first application of 3D high-definition (HD) endoscopic support to the trans-oral surgical treatment of five patients with deep hilo-parenchymal sub-mandibular stones who underwent clinical and ultrasonographic (US) follow-up examinations at one month after the procedure. Five patients undergoing 2D-HD video-assisted transoral surgery for the same condition were used as controls. The results were classified as successful (US - demonstrated complete clearance) or unsuccessful (US - demonstrated total or partial persistence). Visual analogue scales (VAS) were used post-surgically to evaluate the sharpness and brightness of the 2D and 3D images on the screen and stereoscopic depth perception (SDP) of the 3D-HD endoscope. Successful stone removal and significant subjective improvement (lack of obstructive symptoms) was obtained in all but one of the patients in the 3D group, in whom the one-month US evaluation revealed a residual 3 mm asymptomatic hilo-parenchymal stone that was successfully treated by sialendoscopy-assisted intra-corporeal laser lithotripsy. Wharton’s duct and the lingual nerve were identified and preserved in all cases. The mean 3D-HD VAS results were brightness 7 (range 6-8), sharpness 7.8 (range 7-9) and SDP 8.2 (range 8-9); the mean 2D-HD results were brightness 7.8 (range 7-9) and sharpness 7 (range 7-8). Our findings confirm the safety and efficacy of conservative transoral surgical treatment of hilo-parenchymal sub-mandibular stones. From a surgeon’s perspective, 3D-HD guided exploration of the oral floor seems to provide a better view of Wharton’s duct and the lingual nerve, especially near the sub-mandibular parenchyma. The 3D-HD video-assisted transoral removal of deep hilo-parenchymal sub-mandibular stones can therefore be considered a useful new means of preserving the function of an obstructed salivary gland.

Intraductal Pneumatic Lithotripsy after Extended Transoral Duct Surgery in Submandibular Sialolithiasis

Objective

Persistent, residual, or recurrent stones after transoral duct surgery are always associated with hilar to intraparenchymal and/or multiple sialolithiasis, causing difficulties in the treatment. This study was performed to assess the value of intraductal lithotripsy in the treatment of persistent, residual, or recurrent sialolithiasis after extended duct surgery in the submandibular gland.

Study Design

Retrospective study covering February 2015 to June 2018.

Study Setting

Tertiary referral center for salivary gland diseases.

Subjects and Methods

After extended ductal surgery, 39 patients presenting with persistent, residual, or recurrent stones were treated. Four patients had persistent stones; 16 had residual stones; and 19 presented with recurrent stones. Among these patients, 50 stones were treated with intraductal pneumatic lithotripsy. Fragmentation rate, stone-free rate, and symptom-free rate after treatment with intraductal lithotripsy were outcome measures.

Results

Of the 39 patients, 97.4% became stone-free, and all were symptom-free. Ninety-eight percent of the stones were completely fragmented. For 23.1% of the patients, >1 stone was treated with intraductal lithotripsy. All patients with persistent stones, 93.7% of those with residual stones, and all with recurrent stones became stone-free and symptom-free. No severe complications developed.

Conclusions

This study shows that patients presenting with difficult and/or multiple sialolithiasis after extended transoral submandibular duct surgery can be treated with success rates >97%. For multiple sialolithiasis in particular, a multimodal treatment approach with interventional sialendoscopy and intraductal lithotripsy as a central element is a prerequisite for success, as this enables the most difficult part to be performed with high success rates.