Salivary Stones - Nonoperative Removal of Sialoliths and Sialodochoplasy of Salivary Duct Strictures

Objective- To describe the nonsurgical removal of sialoliths and treatment of salivary duct strictures. Design- Case series. Setting- Two 200-bed general community hospitals. Patients- Twelve consecutive patients from April 1985 to November 1994 - 8 with calculi, 3 with salivary duct strictures, and 1 with calculi and strictures. Results- Successful nonoperative removal of calculi in 7 of 9 patients. All four sialodochoplasties were successful. All 10 patients with successful procedures had no recurrent symptoms. Seven patients have been symptom-free for 10 months to ten years. Communication with 3 patients has been impossible recently, although these patients were symptom-free for at least 3 years. To date we have successfully treated twenty-five of twenty-eight patients for salivary duct calculi removal and dilatation of strictures. Conclusions- These methods of nonsurgical sialolith removal and sialodochoplasty were highly successful and should be used as the initial therapies for patients with these conditions.

SIALOLITHIASIS and salivary duct strictures are common pathological conditions of the salivary glands and their ducts. They produce similar symptoms of swelling, pain, and infection as a result of duct obstruction. Swelling and pain usually occur during meals, when salivary secretion is stimulated.Until recently, surgery has been the standard therapy for these conditions. This approach is invasive with important unavoidable risks and complications. Potential risk of damage to the facial nerve is high during parotid gland surgery.Recently, extracorporeal shock wave lithotripsy has been introduced as an alternative treatment of sialolithiasis. Miniature lithotriptors have been developed and show some promise. However, these units are not generally available and their success rates have been variable.The mechanical removal of sialoliths and sialodochoplasty for duct stricture have been our initial approach for these diseases. These minimally invasive procedures are highly effective and avoid the known complications of surgery and anesthesia. Combining these methods with extracorporeal shock wave lithotripsy promises to further increase success rates.

Results:

From April 1985 to November 1994, the mechanical removal of sialoliths was successful in 7 patients with sialolithiasis: 5 with submandibular duct calculi (See Figure 1 below) and 2 with parotid duct calculi (See Figure 2 below). Four patients underwent successful sialodochoplasties, 2 for parotid ducts and 2 for submandibular ducts. One patient had sialoliths and a stricture, so the total number of successful procedures was 11.

In 1 patient, the calculus was located close to the papilla, making retrieval especially difficult because of impaction. A grasping forceps was successfully used and a wide papillotomy was unnecessary.

In 2 patients, calculus retrieval failed: 1 each from the Stensen and Wharton ducts. These were technical failures caused by large impacted calculi and by strictures in the distal segment of the ducts, which made mechanical manipulation impossible. There were no sialodochoplasty failures.

The long-term outcomes following the procedures were excellent. No patient returned with recurrent symptoms. Seven patients remained symptom-free after clinical follow-up from 10 months to 10 years, and 3 patients were symptom-free for 3 to 5 years and then were unavailable for follow-up.

Materials and Methods:

Before the examination, the details of the procedure and its benefits and complications were explained to the patient. Informed consent was obtained for the sialography and for the mechanical removal of the calculi, sialodocholoplasty, or both.

As an initial diagnostic examination, sialography was performed to confirm the location of the strictures and calculi. The papillae were locally anesthetized by direct injection of 1% lidocaine hydrochloride. The papillotomy was accomplished by an incision toward the duct. No sedation or general anesthesia was given.

For the removal of the calculi, a 3.5F 4-wire Dormia basket (Porges, Paliseau Cedex, Salat, France), 3F Segura basket (Microvasive Co [Boston Scientific Corp.], Watertown Mass), and 3F Coaxial Sheath Grasping Forceps (Cook Urological Co, Spencer, Ind) were used. For the sialodochoplasty, 3.8F 3-mm diameter Balloon catheters (Meditech, Watertown, Mass) were used.

After the papillotomy was accomplished, the papilla and adjacent salivary ducts were dilated by 3F and 4F dilators or stiff catheters of the same size. A 0.45-mm guide wire was introduced routinely to guide the balloon catheter. If there was a stricture, balloon dilatation was performed several times until full dilatation was achieved.

For the calculi, a basket was placed beyond or at the calculi site and the basket was manipulated to achieve extraction. When several calculi are present, several attempts may be required.

Comment:

The symptoms of sialoliths and salivary duct stricture are similar: intermittent swelling, tenderness, and pain usually brought on by eating. Infection and sialadenitis are common complications. For a definitive diagnosis, sialography is imperative, especially to diagnose the presence of several calculi or to detect all strictures.

A few cases of balloon-catheter sialodochoplasty and wire-basket removal of caculi have been reported, mainly in foreign journals (ref. 1-3). Also, calculus was removed by an angioplasty balloon catheter (ref. 4).

The most likely surgical management of intraglandular parotid calculi would involve parotidectomy. There does not seem to be a consensus on managing calculi located between the gland hilus and anterior to the masseter muscle. Extraoral parotid sialolithotomy for calculus extraction has been performed under sialographic and ultrasonographic guidance (ref. 5).

The surgical approach to submandibular calculi is influenced by the location of the stone. Palpable stones anterior to the posterior border of the mylohyoid muscle usually are extracted using a transoral incision. When the stone is posterior to the mylohyoid muscle, removal of the entire gland is recommended (ref. 6,7). The complication rate for these procedures and associated anesthesia is not negligible (ref. 8).

In our independent small series during the last 10 years, we have achieved a high success rate. Contrary to other authors' (ref. 5) experience, we did not have difficulty removing parotid calculi located more than 1.5 cm from the papilla, although removal of calculi from the Wharton duct is generally easier than from the Stensen duct. The course and small size of the Stensen duct often makes instrument manipulation difficult. In our 2 cases of failure, the calculi were larger than the ducts and impacted. These ducts had long strictures in their distal segments, which made instrument approach to the calculi and manipulation impossible. A successful removal of this type of calculus was reported with a vascular snare (ref. 9).

Endoscopic laser lithotripsy is unavailable at our institution. Endoscopically controlled laser lithotripsy for removal of a stone in the Stensen duct (ref. 10) and submandibular lithiasis (ref. 11) has been reported. Our 2 cases of failure could have benefited from this method. A success rate of 36% to 53% has been reported for extracorporeal shock wave lithotripsy (ref. 12).

Wehrmann et a1 (ref. 13) developed a miniaturized lithotriptor, and a significantly higher percentage of patients were free of calculi (stone-free rate, 67%) after treatment. The authors did not report whether any case in this series required supplemental mechanical retrieval of calculi.

In conclusion, mechanical removal of calculi and sialodochoplasty by balloon catheter are excellent alternatives to surgery. These procedures are more cost-effective, with reduced risk of morbidity when compared with the surgical alternatives. The long-term outcome following the procedure is excellent. If the mechanical retrieval of calculi fails, laser lithotripsy, extracorporal lithotripsy, or both will improve the success rate.

Dr. Robert B. H. Kim MD is Board Certified in Radiology and Nuclear Medicine with over 37 years of professional experience. To contact Dr. Kim or for more information visit http://www.SalivaryStone.com.