Shockwave lithotripsy of salivary duct stones

Intraoral microscopic-assisted sialolithotomy for management of medium-large submandibular sialolithiasis: A refined technique

Objectives

Sialendoscopy has become the standard treatment for sialolithiasis; however, larger submandibular calculi may require an incisional technique. This study describes and evaluates an intraoral microscopic-assisted sialolithotomy (IMAS) as a refined submandibular stone extraction technique.

Methods

Retrospective case series of 64 submandibular IMAS procedures operated at a tertiary university center and private hospital from 2015 to 2021 were evaluated. Preoperative radiological assessment included noncontrast computed tomography scan ± magnetic resonance sialography. Stone characteristics (side, number, size, and location), operative findings, complications, and postoperative follow-up were reviewed. Success was defined as successful intraoral stone extraction with no symptoms or stone recurrence for at least 12 months postoperatively.

Results

The study included 43 males and 19 females, mean age 38 ± 12 years. Two patients had bilateral stones. All but one operated gland had stones extracted (98.4%), however the true success was 93.8% (60/64) as three patients had recurrent/residual stones within a year. Biggest stone longest diameter was 9.8 ± 4.6 mm (range, 5-30 mm). Hilar and intraglandular stone locations were 73.4% and 6.3%, respectively. Median operative time was 55 min. Adjunctive sialendoscopy was performed in 42.2%. Its use is significantly correlated with having ˃3 stones (mean 3.4 vs. 1.2 stones) [P < 0.001, 95% confidence interval: -3.19 to -1.25]. Minor complications included temporary lingual paresthesia (7.8%) and postoperative ranula (1.6%).

Conclusions

Submandibular IMAS is a highly effective safe technique for stones (≥5 mm). The improved microscopic visualization, illumination and magnification allows addressing all stone locations including intraglandular calculi and enables better lingual nerve identification and preservation.

Factors Precipitating Overnight Admission After Sialolithectomy

OBJECTIVE

To determine factors predicting overnight admission after sialolithectomy.

STUDY DESIGN

Quality outcome database research.

SETTING

The National Surgical Quality Improvement Program American College of Surgeons Participant User Files.

METHODS

Current Procedural Terminology (CPT) codes 42330, 42335, and 42340 between 2007, and 2020 resulted 916 cases. Correlations between perioperative factors and overnight admission (ie, length of stay >0 days) were tested. Cases were stratified into endoscopic (ES) and nonendoscopic (NES) procedures using concurrent CPT codes 42660, 42669, and 42650.

RESULTS

After sialolithectomy, 13.7% (126 cases) were admitted at least overnight. Upon multivariate analysis, wound Class 4 (odds ratio [OR]: 2.15, 95% confidence interval: 1.05, 4.40), American Society of Anesthesiologists (ASA) 3 classification (OR: 2.17, 1.06-4.46, P = .035), and the operative time (OR: 1.01 [1.01-1.01], P < .001) correlated with overnight stay; while Class 2 wounds had a lower risk of overnight admission (OR: 0.31 [0.12-1.63], P < .001). The ES cohort had longer operative times (56.1 vs 73.6 minutes). In the NES cohort's multivariate analysis, ASA III (OR: 2.459 [1.13, 5.34], P < .001) and operative time (OR: 1.01 [1.01, 1.02], P < .001) correlated with overnight stay while Class 2 wound classifications protected against overnight stay (OR: 0.28 [0.15, 0.52], P < .001).

CONCLUSION

This study highlights the correlation between intraoperative complexity, as operative time, wound classification and ASA Class 3, and the need for admission after a typically ambulatory sialolithectomy. The significantly longer operative time with evidence of a shorter length of stay in ES cases suggests a valuable trade off, within the limits of indication.

[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.

Coupling between Osseointegration and Mechanotransduction to Maintain Foreign Body Equilibrium in the Long-Term: A Comprehensive Overview

The permanent interaction between bone tissue and the immune system shows us the complex biology of the tissue in which we insert oral implants. At the same time, new knowledge in relation to the interaction of materials and the host, reveals to us the true nature of osseointegration. So, to achieve clinical success or perhaps most importantly, to understand why we sometimes fail, the study of oral implantology should consider the following advice equally important: a correct clinical protocol, the study of the immunomodulatory capacity of the device and the osteoimmunobiology of the host. Although osseointegration may seem adequate from the clinical point of view, a deeper vision shows us that a Foreign Body Equilibrium could be susceptible to environmental conditions. This is why maintaining this cellular balance should become our therapeutic target and, more specifically, the understanding of the main cell involved, the macrophage. The advent of new information, the development of new implant surfaces and the introduction of new therapeutic proposals such as therapeutic mechanotransduction, will allow us to maintain a healthy host-implant relationship long-term.

Lack of evidence that nephrolithiasis increases the risk of sialolithiasis: A longitudinal follow-up study using a national sample cohort

Objective

The objective of this study was to evaluate the risk of sialolithiasis in nephrolithiasis patients.

Methods

Using data from the national cohort study from the Korean Health Insurance Review and Assessment Service, we selected 24,038 patients with nephrolithiasis. The control group consisted of 96,152 participants without nephrolithiasis who were matched 1:4 by age, sex, income, region of residence, diabetes, hypertension, and dyslipidemia. The incidence of sialolithiasis in the two groups was compared, with a follow-up period of up to 12 years. The crude and adjusted hazard ratio (HR) of nephrolithiasis to sialolithiasis was analyzed with a Cox-proportional hazard regression model.

Results

The rates of sialolithiasis in the nephrolithiasis group and the control group were not significantly different (0.08% vs. 0.1%, P = 0.447). The crude and adjusted hazard ratios of nephrolithiasis to sialolithiasis were not statistically significant (crude HR = 0.82, 95% confidence interval [CI] = 0.50–1.35, P = 0.448; adjusted HR = 0.81, 95% CI = 0.49–1.33, P = 0.399). Subgroup analyses according to age and sex also failed to reveal statistical significance.

Conclusion

There is no evidence of an increased risk of sialolithiasis associated with nephrolithiasis. We suggest that routine evaluation for sialolithiasis in all patients with nephrolithiasis is not necessary.

Extracorporeal lithotripsy of salivary gland stone: A 55 patients study

Sialolithiasis are the most frequent salivary gland disease, mainly affecting the submandibular gland. With the advent of minimally invasive techniques, total salivary gland removal should not be considered as the first-line treatment anymore. Extracorporeal Shock Wave Lithotripsy (ESWL) is an alternative to surgery preserving the gland. The objective of our retrospective study was to evaluate the efficiency of ESWL on pain and obstructive syndrome in patients suffering from sialolithiasis. The global result felt by the patients was also considered. All patients treated between October 2009 and July 2016 for sialolithiasis by ESWL in our department were included. They were divided into two groups according to the concerned gland: a parotid gland (PG) and a submandibular gland (SMG) group. Our retrospective telephone questionnaire consisted in 4 questions about their symptomatology before and after ESWL, including pain self-evaluation before and after treatment. They were finally asked to evaluate the global result of the ESWL treatment: excellent, good, mean, or poor. In total, 55 patients were included in this study, 38 patients in PG group and 17 patients in SMG group. We observed a decrease of pain and obstructive syndrom after ESWL procedure in both groups. Better results were found on the obstructive syndrome in the PG group. Very few side-effects were reported by patients. Given that it has very few side effects, ESWL can easily be considered as first line treatment for sialolithiasis to avoid heavier treatments such as surgery. It should be the first-line treatment for symptomatic parotid sialolithiases. The treatment of symptomatic submandibular sialolithiases depends on the topography of the lithiasis.

Giant Submandibular Calculus Eroding Oral Cavity Mucosa

Sialolithiasis is the formation of calculi or sialoliths in the salivary gland. It is the most common benign condition of the salivary gland. Sialolithiasis can occur in all salivary glands. The submandibular gland is most commonly affected followed by the parotid gland. Calculi commonly measure less than 10 mm. Calculi of more than 15 mm are termed giant salivary gland calculi and are infrequently reported in the literature. Here, we report a case of unusually large submandibular gland calculus of 5 cm in greatest dimension which caused erosion of the oral cavity.

Salivary lithotripsy in the era of sialendoscopy

The traditional management of obstructive salivary disorders has been replaced by minimally-invasive gland-preserving techniques including shock-wave lithotripsy, sialendoscopy, interventional radiology and endoscopically video-assisted trans-oral and cervical stone retrieval, of which sialendoscopy is considered to be the method of first choice. Primary endoscopically controlled stone extraction without prior fragmentation is only possible in 15-20% of cases; in more than 80%, fragmentation is necessary because of the size, impactation and location of the stone, or an alternative treatment such as transoral duct surgery or combined approaches are required. Moreover, about 10-20% of all stones cannot be adequately accessed by means of a sialendoscope or any alternative surgical method and, in such cases, extra-corporeal shock wave lithotripsy (ESWL) is the treatment of choice. However, in endoscopically accessible stones, ESWL is being gradually replaced by endoscopically assisted intra-corporeal techniques, including endoscopically guided laser and pneumatic intracorporeal lithotripsy. We describe the currently most widely used techniques for salivary lithotripsy, including ESWL, and endoscopically guided laser, electrohydraulic, electrokinetic and pneumatic intra-corporeal lithotripsy, and discuss their indications given the widespread use of advanced rehabilitative sialendoscopy and combined therapeutic approaches.

Intracorporeal electrokinetic lithotripsy: an advancement in minimally invasive management of parotid duct calculus

Background:

Symptomatic salivary stones in the middle or proximal parotid duct have previously been treated by gland excision, which is associated with a 3–7 per cent risk to the facial nerve. Minimally invasive approaches to the management of salivary duct calculi have been devised over the past decade. Fluoroscopically guided basket retrieval, lithotripsy and intra-oral stone removal under general anaesthesia have found favour with most surgeons. Endoscopically controlled intracorporeal shock wave lithotripsy using the pneumoblastic lithotripter has been replaced by electrohydraulic lithotripsy (used in sialolith treatment).

Method:

The electrokinetic lithotripter is normally used for the treatment of lower ureteric stones, and has the benefit of minimal concomitant tissue damage. We have extended its use to the treatment of parotid duct calculi. We present initial results for its use in the treatment of a proximal parotid duct stone.

Result:

Application of the shock wave to the stone under direct vision avoided injury to the duct or to any local structure. The patient made an uneventful recovery and was asymptomatic after 18 months' follow up.

Conclusion:

Continuous, endoscopically monitored electrokinetic lithotripsy with good irrigation gives a well illuminated field and absolute delivery of energy to the target. It avoids the side effects caused by impact of the shock wave on the parotid duct and adjacent anatomical structures, thereby making it a safer procedure.

Transoral submandibulotomy for deep hilar submandibular gland sialolithiasis

OBJECTIVES/HYPOTHESIS

To assess the long-term results after transoral submandibulotomy for stones located in the deep hilar and intraparenchymal submandibular region.

STUDY DESIGN

Retrospective cohort analysis.

METHODS

Retrospective evaluation including all patients treated with transoral submandibulotomy for sialolithiasis at a tertiary referral center.

RESULTS

Complete stone removal at the first transoral surgical treatment was achieved in 185 of 234 patients (79.1%). One hundred seventy-five of the 234 patients were followed up for a mean of 31.2 ( ± 20.5) months. During the follow-up period, 140 of the 175 patients (80.0%) became symptom free after one operation. In patients with residual symptoms, no further treatment was needed in 12 patients (6.9%) due to the mildness of the symptoms; 23 patients (13.1%) received further therapy, which was successful in 15 cases. Submandibulectomy only had to be performed in 3.4% of the patients with follow-up (6/175). In a questionnaire survey, 91.4% of the patients stated that they would be prepared to have the same operation again.

CONCLUSIONS

These findings show that transoral removal of submandibular sialoliths located in the deep hilum or adjacent intraglandular parenchyma is an effective treatment that can be assisted by additional measures. The techniques described show high success rates, good long-term results, low complication rates, and they avoided the need for submandibulectomy in >95% of cases.

LEVEL OF EVIDENCE

4. Laryngoscope, 127:2038-2044, 2017.

Sonographic Evaluation of Sialolithiasis

Salivary gland diseases are relatively common disorders. One of these is salivary calculi (sialoliths), which occurs in the submandibular and parotid glands of middle-aged adults. These are relatively common and often give rise to inflammation and infection of the gland. Radiologic methods used to evaluate these stones include computed tomography, magnetic resonance imaging, and sialography. With improvements in diagnostic ultrasound equipment and, very recently, amplitude power mapping, the diagnosis of sialolithiasis and sialodochitis was made non-invasively. This is the first report of sialodochitis diagnosed using amplitude power mapping.

Histopathology of Submandibular Glands Removed for Sialolithiasis

We reviewed the clinical history of 48 consecutive patients who underwent submandibular gland removal for radiologically proven sialolithiasis. The specimens were examined by a pathologist blinded to the clinical data. A histopathologic classification into 1 of 3 grades was established by evaluating the degrees of atrophy, fibrosis, and inflammation. A correlation between the clinical and pathological variables was sought in order to define clinical variables that would predict abnormal submandibular glands that required extirpation. A significant percentage of the submandibular glands exhibited normal histologic findings. The patients with normal submandibular glands had a clinical evolution similar to that of other patients with severely damaged glands. The only clinical variable that correlated with increased histopathologic alteration was the patient's age. In view of the newly available diagnostic and therapeutic techniques for sialolithiasis, a conservative attitude to submandibular gland resection appears justified.

Extracorporeal Shock Wave Lithotripsy of Submandibular Stones: Evaluation after 10 Years

The use of extracorporeal shock waves in the treatment of submandibular stones is a minimally invasive approach for the treatment of this disease. Its clinical significance has been determined in a long-term retrospective study, performed as follow-up to the short-term results. From 1989 to 1994, 197 patients (88 female, 109 male; age range, 8 to 83 years) with symptomatic, sonographically detectable concretions of the submandibular gland were treated with extracorporeal shock wave lithotripsy. The review analysis was completed retrospectively in 2002 and included 191 patients with complete data. The period under review ranged from 8 to 13 years, with an average of 10.5 years. Altogether, 67 of the 191 patients (35%) either were free of stones or had no more symptoms from the residual sialoliths. Another 15% had a significant improvement in their symptoms and required no further therapy. The remaining 95 patients (50%) had residual stones; they had no symptoms in the short review period, but have had symptoms since. The therapeutic success was not influenced by the stone size, but rather by the stone location within the gland. After therapy, no severe side effects were identified. Extracorporeal shock wave lithotripsy is a possible treatment for stones in the submandibular gland. In combination with other gland-preserving methods, it now forms part of a multitherapeutic approach that renders submandibulectomy unnecessary in the majority of cases.

Sialolithiasis. Proposal for a new minimally invasive procedure: Piezoelectric surgery

Sialolithiasis is the presence of stones in the ducts of the salivary glands. Most episodes are unique, and 60-80% are located exclusively in the main excretory duct. The main clinical manifestations are swelling and pain typically before, during or after meals that decreases if the obstruction is not complete. The highest prevalence of lithiasis is in the submandibular gland -87%-, whose secretion is more viscous, followed by the parotid gland -10%- and finally the sublingual gland -3%-. The most significant consequences are caused by the prolonged blockage of the duct by a stone, which can produce a persistent ductal dilatation with a swelling that does not subside, and could lead to the complete degeneration of the parenchyma, becoming a hot spot where secondary infections may occur, leading to acute bacterial sialadenitis or glandular abscesses. Treatment options range from a single probing extraction, extraction with sialographic control using the sialoendoscope, LASER intraductal lithotripsy, lithotripsy extracorporeal shock wave (ESWL), to the surgical techniques combining open duct with endoscopic or glandular removal. We propose, with regard to a case, the use of a simple piezoelectric device which, tunnelling through the glandular channel by the ostium, allows stone fragmentation, without damaging the surrounding soft tissue. Stone removal by this less invasive method reduces the need for more complex and expensive techniques. The postoperative course without retraction of the ostium, and the regaining of functionality is favourable.

Key words:Calculus, lithotripsy, minimally invasive therapy, piezoelectric surgery, salivary glands, soft tissues.

Giant sialoliths of submandibular gland duct: Report of two cases with unusual shape

Giant sialoliths are classified as those exceeding 15 mm in any one dimension. Although, large sialoliths have been described in the body of salivary glands, they are rarely found in the salivary ducts, particularly when the patients have no painful symptoms. Sialolithiasis is one of the most common diseases of the salivary glands in middle-aged patients and approximately 80% of all reported cases of sialoliths occur in the submandibular gland. Here, we report two cases of giant sialolith of submandibular gland duct. Interestingly, sialolith found in one of our cases had an unusual similarity with the canine tooth and mimicking it in both size and shape. In both cases the calculus was removed surgically via intraoral approach. No recurrence was seen in any of the cases on follow-up.

Ho:Yag Laser for Sialolithiasis of Wharton’s Duct

Objective

To assess the feasibility of intracorporeal lithotripsy with holmium YAG laser under sialoendoscopic guidance for sialolithiasis of Wharton’s duct.

Study Design

Case series with planned data collection.

Setting

Tertiary referral university hospital.

Methods

This study was conducted on 16 patients with sialolithiasis of Wharton’s duct. Diagnosis was confirmed at ultrasound examination. Patients with stones ranging from 5 to 8 mm in diameter were enrolled in the study. The selected patients underwent intracorporeal lithotripsy with holmium Yag laser under endoscopic control. Debris was removed using sialoendoscopic forceps or a wire basket during the same procedure. After a 3-month follow-up, radiological tests were rerun.

Results

Stone fragmentation was possible in all cases. All patients experienced a regular postoperative course. Postoperative ultrasound examinations revealed residual stones in 3 patients, 1 of whom was asymptomatic. Three patients complained of residual symptoms after 3 months of follow-up. These patients were treated successfully during a second sialoendoscopic procedure.

Conclusions

In our experience, endoscopic laser lithotripsy was proved to be a feasible technique for Wharton’s duct lithiasis in clinical practice.

Sialolithiasis in the duct of submandibular gland: a case report in patient with epidermolysis bullosa

AIM

To describe the options of treatment to remove a sialolith associated with the submandibular gland duct in a patient with epidermolysis bullosa (EB).

BACKGROUND

Treatment of patients with EB is very complex and involves a multidisciplinary team. This condition is characterized by a spectrum of blistering and mechanical fragility of the skin. One main feature of this disease is the esophageal constriction and possible constriction to the submandibular duct. This alteration may induce the formation of calculi in this duct, which is called sialolith. Once the sialolith obliterates the trajectory of the duct this will lead to a sialolithiasis. The calculi have to be removed.

CASE REPORT

Seventeen years old female patient with dystrophic EB developed a sialolith at the submandibular duct. She has a limited mouth opening and her tongue was collapsed with mouth floor. The first choice of treatment was the lithotripsy, once this procedure is less invasive and a surgical remove could worse the collapsed tongue. She was with acute pain and with a great augmentation in the submandibular area. Once the patient was debilitated and has difficult to swallow she invariably needed to be hospitalized in order to receive intravenous medication. During the hospitalization the sialolith could be seen through the opening of the duct and the calculi was removed with local anesthesia.

CONCLUSION

The treatment of sialolithiasis usually does not present major challenges, nevertheless if the sialolithiasis is associated with EB, the treatment became an extremely challenge. In this particular case the option of treatment was the less invasive.

CLINICAL RELEVANCE

This case report has an enormous clinical relevance once there is no protocol to treat patients with EB and buccal diseases.

Effects of shock waves on oxidative stress in parotid gland of rat

This study was designed to investigate whether extracorporeal shock wave lithotripsy (ESWL) exposure to parotid gland produces an oxidative stress in parotid glands of rats. Twelve male Wistar-albino rats, 6 months of age with an average body weight of 250-300 g, were divided randomly into two groups, each consisting of six rats. The animals in the first group did not receive any treatment and served as control. The left parotid glands of animals in group 2 (ESWL treated) received a thousand 18 kV shock waves after anesthetizing the rats with 50 mg/kg of ketamine. The animals in both groups were killed 72 hours after the ESWL treatment, and the parotid glands were harvested for the determination of lipid peroxidation product malondialdehyde (MDA), antioxidant glutathione (GSH) levels and the activities of antioxidant enzymes such as superoxide dismutase (SOD), GSH-Px and catalase (CAT). It was found that MDA level increased in parotid glands of rats after the ESWL treatment. The SOD, GSH-Px and CAT enzyme activities, and the level of antioxidant GSH decreased in parotid gland of rats after the ESWL treatment. It was concluded that short-term ESWL treatment caused an increase in the free radical production and a decrease in the antioxidant enzyme activity in parotid glands of ESWL-treated rats.

A Large Sialolith Perforating the Wharton's Duct: Review of Literature and a Case Report

Sialolithiasis accounts for the most common cause of diseases of salivary glands. The majority of sialoliths occur in the submandibular gland or the Wharton's duct. This article discusses review of literature, predisposing factors, signs and symptoms, diagnostic methods and various modalities available for the management of sialolithiasis. This case report presents a case of sialolith of a large size in the left Wharton's duct, which was explored and removed via an intra-oral approach.

Mechanisms of primary blast-induced traumatic brain injury: insights from shock-wave research

Traumatic brain injury caused by explosive or blast events is traditionally divided into four phases: primary, secondary, tertiary, and quaternary blast injury. These phases of blast-induced traumatic brain injury (bTBI) are biomechanically distinct and can be modeled in both in vivo and in vitro systems. The primary bTBI injury phase represents the response of brain tissue to the initial blast wave. Among the four phases of bTBI, there is a remarkable paucity of information about the cause of primary bTBI. On the other hand, 30 years of research on the medical application of shockwaves (SW) has given us insight into the mechanisms of tissue and cellular damage in bTBI, including both air-mediated and underwater SW sources. From a basic physics perspective, the typical blast wave consists of a lead SW followed by supersonic flow. The resultant tissue injury includes several features observed in bTBI, such as hemorrhage, edema, pseudoaneurysm formation, vasoconstriction, and induction of apoptosis. These are well-described pathological findings within the SW literature. Acoustic impedance mismatch, penetration of tissue by shock/bubble interaction, geometry of the skull, shear stress, tensile stress, and subsequent cavitation formation, are all important factors in determining the extent of SW-induced tissue and cellular injury. Herein we describe the requirements for the adequate experimental set-up when investigating blast-induced tissue and cellular injury; review SW physics, research, and the importance of engineering validation (visualization/pressure measurement/numerical simulation); and, based upon our findings of SW-induced injury, discuss the potential underlying mechanisms of primary bTBI.

[Modern concepts for the diagnosis and therapy of sialolithiasis]

Sialoliths are the underlying cause of salivary gland obstructive disease in 60%-70% of cases. Modern minimally invasive techniques have enabled accurate diagnosis and findings-specific therapy with the aim of full gland-function preservation. This article provides an overview of the current diagnostic measures for and therapy of sialolithaisis. Ultrasound is the investigation of first choice and is able to recognize stones in well over 90% of cases. Sialendoscopy is a directly visualizing technique which is superior to all other diagnostic measures for the assessment of pathologic changes in the salivary duct system and the detection of stones. Treatment was significantly improved with the introduction of extracorporal shock wave lithotripsy (ESWL), sialographic-controlled techniques, surgical procedures of the duct system and in particular by interventional sialendoscopy. Interventional sialendoscopy, especially when combined with other treatment modalities, has a success rate of 85%-95%. Cases which respond poorly to therapy can be treated successfully with the endoscopic transcutaneous approach in about 90% of cases. When sialendoscopy is performed in combination with other minimally invasive treatment options the gland can be preserved in 95%-98% of all cases.

Extracorporeal lithotripsy techniques for salivary stones

Over the past 20 years, development of minimally invasive therapies has led to the use of extracorporeal shock wave lithotripsy (ESWL) to treat salivary stones. The two main energy sources are piezoelectric and electromagnetic extracorporeal lithotripsy. Both have the aim of fragmenting the stones. ESWL is considered the treatment of choice for all parotid calculi and submandibular perihilar or intraparenchymal stones of less than 7 mm. Continuous ultrasonographic monitoring during the procedure reduces the number of untoward effects. The main limitations are the need for multiple sessions and residual stone fragments inside the duct system.

Combined Endoscopic and Transcutaneous Approach for Parotid Gland Sialolithiasis: Indications, Technique, and Results

OBJECTIVE: Despite all the advances of minimally invasive surgery, refractory stones remain in 10 to 20 percent of all cases of parotid gland sialolithiasis, and persistence of the symptoms makes removal of the gland inevitable. In some of these cases, however, it may be possible to conserve the gland using a combination of endoscopic and transcutaneous procedures.

STUDY DESIGN: Case series with chart review.

SETTING: Tertiary referral center.

SUBJECTS AND METHODS: Nine patients treated with a combined endoscopic transcutaneous operation were evaluated. During this procedure, the stone is removed through a skin incision under endoscopic guidance. Indications were sialolithiasis refractory to treatment (n = 5), sialolithiasis with complications (n = 2), contraindications to primary minimally invasive surgery (n = 1), and primary treatment (n = 1). In seven cases, the stones were extracted. Simultaneous resection of a sialocele was carried out in one case, and simultaneous resection of a saliva-cutaneous fistula was carried out in another. A stent was inserted in 66.7 percent of the cases.

RESULTS: Treatment was successful in 88.9 percent of the patients. All of these patients were free of stones and symptoms, and glandular function was maintained both clinically and on ultrasound assessment. Complete parotidectomy had to be carried out in one case because it was not possible to reconstruct the duct system.

CONCLUSION: The combined operation offers a further option for gland-conserving treatment in cases with obstructive salivary gland disease, especially sialolithiasis. At present, it is indicated for cases that are resistant to treatment after sialendoscopy or extracorporeal shock wave lithotripsy. The gland resection rate can thus be further reduced.

Effects of Low-energy Shock Waves on Oral Bacteria

We have recently demonstrated that extracorporeal shock-wave therapy (ESWT) is effective in promoting the healing of dermal wounds and in regenerating alveolar bone lost through periodontal disease. The objective of the present study was to determine any antibacterial effect of ESWT on oral bacteria. Monoculture suspensions of 6 bacterial species were treated with 100 to 500 pulses of ESWT at energy flux densities (EFD) of 0.12 mJ/mm2, 0.22 mJ/mm2, and 0.3 mJ/mm2. Following treatment, aliquots were plated for viability determination and compared with untreated controls. ESWT showed a significant microbicidal effect for Streptococcus mutans and an unencapsulated strain of Porphyromonas gingivalis following as few as 100 pulses at 0.3 mJ/mm2 (p ≤ 0.001). In addition, a significant disruption of bacterial aggregates was observed at lower EFDs. No significant reduction in viability was observed for all other bacteria at EFDs and pulses tested (p > 0.05). These findings suggest that low-energy ESWT may be bactericidal for selected oral bacteria.

Extracorporeal shock wave therapy for management of chronic ulcers in the lower extremities

Management of chronic ulcers in the lower extremities is still a challenge for patients and health providers. Recent studies showed extracorporeal shock waves (ESW) as effective in stimulating growth factors, inducing angiogenesis and healing of fractures and injuries. This study was planned to investigate the opportunity of introducing the ESW in the treatment of chronic wounds. Thirty consecutive patients with chronic posttraumatic, venous and diabetic ulcers, unresponsive to conservative or advanced dressing treatments, were counseled about the use of ESW as alternative treatment for their wounds. Thirty-two wounds were treated and 16 wounds healed completely within six sessions of ESW. In all of the nonhealed wounds, decrease of the amount of exudates, increased percentage of granulation tissue compared with fibrin/necrotic tissue and decrease of wounds' size were statistically significant after four to six sessions of ESW (p < 0.01). Significant decrease of pain was reported (p < 0.001). Comparison with a control group of 10 patients with chronic ulcer treated on the basis of regular dressings confirmed the statistical significant improvement in the healing process (p < 0.01). ESW therapy seems to be a safe, feasible and cost-effective treatment for chronic ulcers in the lower extremities. Further research and clinical trials are necessary to evaluate dose and time intervals of sessions to standardize a protocol of treatment in the management of chronic wounds.

Giant Sialolith of the Submandibular Salivary Gland

We report the case of a 48-year-old man who had an unusually large submandibular gland sialolith (2.6 cm in greatest dimension), which led to sialadenitis and subsequent abscess formation. We describe the management of this patient and review the literature with emphasis on the various modalities available for diagnostic imaging.

Pressure-dependent effect of shock waves on rat brain: induction of neuronal apoptosis mediated by a caspase-dependent pathway

OBJECT

Shock waves have been experimentally applied to various neurosurgical treatments including fragmentation of cerebral emboli, perforation of cyst walls or tissue, and delivery of drugs into cells. Nevertheless, the application of shock waves to clinical neurosurgery remains challenging because the threshold for shock wave-induced brain injury has not been determined. The authors investigated the pressure-dependent effect of shock waves on histological changes of rat brain, focusing especially on apoptosis.

METHODS

Adult male rats were exposed to a single shot of shock waves (produced by silver azide explosion) at overpressures of 1 or 10 MPa after craniotomy. Histological changes were evaluated sequentially by H & E staining and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling (TUNEL). The expression of active caspase-3 and the effect of the nonselective caspase inhibitor N-benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (Z-VAD-FMK) were examined to evaluate the contribution of a caspase-dependent pathway to shock wave-induced brain injury. High-overpressure (> 10 MPa) shock wave exposure resulted in contusional hemorrhage associated with a significant increase in TUNEL-positive neurons exhibiting chromatin condensation, nuclear segmentation, and apoptotic bodies. The maximum increase was seen at 24 hours after shock wave application. Low-overpressure (1 MPa) shock wave exposure resulted in spindle-shaped changes in neurons and elongation of nuclei without marked neuronal injury. The administration of Z-VAD-FMK significantly reduced the number of TUNEL-positive cells observed 24 hours after high-overpressure shock wave exposure (p < 0.01). A significant increase in the cytosolic expression of active caspase-3 was evident 24 hours after high-overpressure shock wave application; this increase was prevented by Z-VAD-FMK administration. Double immunofluorescence staining showed that TUNEL-positive cells were exclusively neurons.

CONCLUSIONS

The threshold for shock wave-induced brain injury is speculated to be under 1 MPa, a level that is lower than the threshold for other organs. High-overpressure shock wave exposure results in brain injury, including neuronal apoptosis mediated by a caspase-dependent pathway. This is the first report in which the pressure-dependent effect of shock wave on the histological characteristics of brain tissue is demonstrated.

Long-term evaluation of extracorporeal shock wave lithotripsy in the treatment of salivary stones

Extracorporeal shock wave lithotripsy is a rather new therapeutical method in the treatment of sialolithiasis. The objective was to evaluate retrospectively the results of the extracorporeal shock wave lithotripsy therapy performed with a Minilith SL 1 lithotripter on 167 out-patients with symptomatic stones (average size 5.94 mm) of the salivary glands over an observation period of seven years. A successful treatment with total stone disintegration was achieved in 51 (31 per cent) patients. In 92 (55 per cent) patients treatment was partially successful, with disappearance of the symptoms but a sonographically still identifiable stone. Treatment failure occurred in 24 (14 per cent) patients who then underwent surgery. The mean follow-up period was 35.6 months (minimum three, maximum 83), after which 83.2 per cent of the initially successfully treated patients were still free of symptoms.Therefore, extracorporeal shock wave lithotripsy, as a non-invasive treatment alternative with few side effects, is an efficient technique for the therapy of sialolithiasis in selected patients.

Unusual Asymptomatic Giant Sialolith of the Submandibular Gland

This report presents an unusual case of asymptomatic sialolith of the submandibular gland. A 61-year-old man was referred to our department for multiple extractions. An ortopantomographic exam revealed the existence of a large radiopacity in the right premolar mandibular region. The patient was completely asymptomatic and no episodes of pain and swelling had occurred in the previous years. Ultrasonography and clinical examination confirmed the diagnosis of sialolithiasis of the submandibular duct. The calculus was removed trans-orally in local anaesthesia. The sialolith measured 22 mm and it was mainly constituted by phosphate, calcium and smaller amounts of magnesium. The bacteriological exam revealed the presence of Streptococcus Mitis, Streptococcus Salivarius and non-pathogenic Neisserie. Postoperative course was uneventful. Even a sialolith of significant dimensions may not be symptomatic. Nevertheless, the likelihood of future complications may constitute an indication for surgical removal of abnormal asymptomatic sialoliths.

Possible etiology of calculi formation in salivary glands: biophysical analysis of calculus

Sialolithiasis is one of the common diseases of the salivary glands. It was speculated that, in the process of calculi formation, degenerative substances are emitted by saliva and calcification then occurs around these substances, and finally calculi are formed. However, the exact mechanism of the formation of calculi is still unclear. In this study, we identify some possible etiologies of calculi formation in salivary glands through biophysical analysis. Calculi from 13 patients with submandibular sialolithiasis were investigated by transmission electron microscopy, scanning electron microscopy, X-ray microanalyzer, and electron diffraction. Transmission electron microscopic observation of calculi was performed in the submandibular gland (n = 13). In 3 of the 13 cases, a number of mitochondria-like structures and lysosomes were found near calcified materials. Scanning electron microscopic examination of these materials revealed that there were lamellar and concentric structures and that the degree of calcification was different among the calculi. X-ray microanalysis disclosed the component elements in the calculi to be Ca, P, S, Na, etc., and the main constituents were Ca and P. The calcium-to-phosphorus ratio was 1.60-1.89. Analysis of the area including mitochondria-like structures, lysosomes, and the fibrous structures by electron diffraction revealed the presence of hydroxyapatite and calcified materials. It is speculated that mitochondria and lysosomal bodies from the ductal system of the submandibular gland are an etiological source for calcification in the salivary gland.

Ultrasound guided lithotripsy of salivary calculi using an electromagnetic lithotriptor

Sialolithiasis is a common disease of the major salivary glands. A supplement to the traditional therapies is extracorporeal shock wave lithotripsy of the calculus. This method has been adopted from the therapy of renal or bladder calculi. Patients with a solitary calculus of parotid or submandibular gland were treated with a specially designed lithotriptor. In a retrospective study the results of this therapy were analysed. The success rate was far better for parotid gland calculi than for submandibular calculi. We could not find better results than those published in literature with other devices. In our therapeutic concept, sialolithotripsy is the therapy of first choice for single parotid gland calculi. For submandibular gland calculus this method is advisable in selected cases only.

Endoscopie des canaux salivaires : toujours plus petit, toujours plus loin ?

Sialendoscopy is a new minimally invasive technique allowing exploration of the submandibular and parotid ducts with treatment for sialolithiasis and stenosis. Used for diagnostic purposes, sialendoscopy may be an alternative to classical radiological methods. As an interventional technique, it allows a significant reduction in the number of indications for submandibular and parotid resections.

Speichelsteine der Glandula submandibularis

BACKGROUND

Sialolithiasis as a cause of sialadenitis within Wharton's duct accounts for more than 80% of all cases. In the past extirpation of the gland was carried out in nearly all cases. Gland-preserving therapies such as transoral removal have so far been seldom examined.

PATIENTS AND METHODS

In 683 patients suffering from submandibular lithiasis with a mean age of 45 years (8-87 years) transoral removal of the stones were carried out. The follow-up period was 1-7 years. The stone location was distal to the edge of the mylohyoid muscle in 283 cases and more proximal to the gland within the hilum in 296 patients (single concrements). Fifty-nine patients had two separate stones, one within the area of the hilum and other smaller ones proximal within the gland.

RESULTS

All patients with distal stone location, 89% of patients with single stones of the perihilar region, and 63% of the patients with two separate stones in the hilum and parenchyma were free of stones. Another 8 and 23%, respectively, had small residual concrements without any complaints. Recurrence of lithiasis or damage of the lingual nerve remained below 1%.

CONCLUSION

Transoral removal in palpable sialoliths should be considered as the treatment of choice in patients suffering from submandibular stones located within the floor of the mouth or within the perihilar region of the gland. Ultrasound imaging is important for exact location of the stones.

Antibacterial effects of extracorporeal shock waves

Despite considerable knowledge about effects of extracorporeal shock-wave therapy (ESWT) on eukaryotic tissues, only little data are available concerning their effect on prokaryotic microorganisms. The objective of the present study was to determine the bactericidal activity as a function of energy flux density and shock-wave impulse number. Standardised suspensions of Staphylococcus aureus ATCC 25923 were exposed to different impulse numbers of shock waves with an energy flux density (ED) up to 0.96 mJ mm(-2) (2 Hz). Subsequently, viable bacteria were quantified by culture and compared with an untreated control. After applying 4000 impulses, a significant bactericidal effect was observed with a threshold ED of 0.59 mJ mm(-2) (p < 0.05). A threshold impulse number of more than 1000 impulses was necessary to reduce bacterial growth (p < 0.05). Further elevation of energy and impulse number exponentially increased bacterial killing. ESWT proved to exert significant antibacterial effect in an energy-dependent manner. Certain types of difficult-to-treat infections could offer new applications for ESWT.

Application of shock waves as a treatment modality in the vicinity of the brain and skull

OBJECT

Shock waves have not previously been used as a treatment modality for lesions in the brain and skull because of the lack of a suitable shock wave source and concerns about safety. Therefore, the authors have performed experiments aimed at developing both a new, compact shock wave generator with a holmium:yttrium-aluminum-garnet (Ho:YAG) laser and a safe method for exposing the surface of the brain to these shock waves.

METHODS

Twenty male Sprague-Dawley rats were used in this study. In 10 rats, a single shock wave was delivered directly to the brain, whereas the protective effect of inserting a 0.7-mm-thick expanded polytetrafluoroethylene (ePTFE) dural substitute between the dura mater and skull before applying the shock wave was investigated in the other 10 rats. Visualizations on shadowgraphy along with pressure measurements were obtained to confirm that the shock wave generator was capable of conveying waves in a limited volume without harmful effects to the target. The attenuation rates of shock waves administered through a 0.7-mm-thick ePTFE dural substitute and a surgical cottonoid were measured to determine which of these materials was suitable for avoiding propagation of the shock wave beyond the target.

CONCLUSIONS

Using the shock wave generator with the Ho:YAG laser, a localized shock wave (with a maximum overpressure of 50 bar) can be generated from a small device (external diameter 15 mm, weight 20 g). The placement of a 0.7-mm-thick ePTFE dural substitute over the dura mater reduces the overpressure of the shock wave by 96% and eliminates damage to surrounding tissue in the rat brain. These findings indicate possibilities for applying shock waves in various neurosurgical treatments such as cranioplasty, local drug delivery, embolysis, and pain management.

Sialolithiasis: an unusually large submandibular salivary stone

Salivary gland calculi account for the most common disease of the salivary glands. The majority of sialoliths occur in the submandibular gland or its duct and are a common cause of acute and chronic infections. This case report describes a patient presenting with an unusually large submandibular gland sialolith, the subsequent patient management, the aetiology, diagnosis and various treatment modalities available for management of salivary gland calculi depending on their site and size.

Effects of electrohydraulic extracorporeal shock wave lithotripsy on submandibular gland in the rat: electron microscopic evaluation

OBJECTIVES

Extracorporeal shockwave lithotripsy (ESWL) has been applied in sialolithiasis as a new treatment modality. The aim of this experimental study is to investigate the local effects of electrohydraulic ESWL applied to the right submandibular gland of the rats.

METHODS

This prospective study was conveyed in four groups; groups I, II, III and IV; each group consisting of 20, 20, 18 and 9 rats, respectively, with a randomized distribution. Groups I, II, III and IV received 250, 500, 1000 and 2000 shock waves at 14-16 kV (average 15.1 kV), respectively, to the right submandibular glands on the 0th day. In groups I, II, III, right submandibular glands of the rats were removed on the 0th, 1st, 7th and 15th days; in group IV, this procedure could be managed only on the 0th and 7th days. Light and electron microscopic evaluation were assessed. Using the light microscopic changes, severity of damage score of the glands (SDS) was found. Statistical analysis was done using SDSs.

RESULTS

Light and electron microscopic observations have shown that the damage produced by the shock waves were confined to focal areas in the acinar cells (AC), granulated convoluted tubule (GCT) cells and blood vessels at all doses applied. Vacuolization in the cytoplasms of the AC and GCT cells, disintegration of membranes, alteration in the cytoplasmic organization, swelling of the mitochondria and loss of the features were observed on electron microscopy. Increase in the secretion rate; stasis and dilatation in the blood vessels; blebbing and loss of features in the cytoplasm of the endothelial cells were observed. According to the result of the statistical analysis using SDSs; at 250 shock wave dose, a statistically significant difference between the SDSs of the days (0th, 1st, 7th and 15th) was found (P<0.05). The SDS on the 0th day was found to have the lowest value among the other days. And also a statistically significant difference was found on the 0th day between the SDSs at doses of 250, 500, 1000 and 2000 shock waves (P<0.05). The SDS at 250 and 500 shock waves was found to have the lower value than the SDS at the 2000 shock wave. It was observed that produced damage was less prominent by small doses (250, 500 doses) initially (0th day). Electrohydraulic ESWL caused a "patchy type" generalized pathology on submandibular glands of the rats and damaged focal areas were widespread all through the gland from the 1st day on.

CONCLUSION

Formation of the damage was concluded to be related to the direct effect of the shock waves rather than the dose used. Electrohydraulic lithotripters are not suitable for sialolithiasis because of the focus problems, local tissue damage and the risk of the damage to the adjacent structures.