Cone beam computed tomography (CBCT) sialography--an adjunct to salivary gland ultrasonography in the evaluation of recurrent salivary gland swelling

Ultrasound-based jawbone surface quality evaluation after alveolar ridge preservation

BACKGROUND

Bone readiness for implant placement is typically evaluated by bone quality/density on 2-dimensional radiographs and cone beam computed tomography at an arbitrary time between 3 and 6 months after tooth extraction and alveolar ridge preservation (ARP). The aim of this study is to investigate if high-frequency ultrasound (US) can classify bone readiness in humans, using micro-CT as a reference standard to obtain bone mineral density (BMD) and bone volume fraction (BVTV) of healed sockets receiving ARP in humans.

METHODS

A total of 27 bone cores were harvested during the implant surgery from 24 patients who received prior extraction with ARP. US images were taken immediately before the implant surgery at a site co-registered with the tissue biopsy collection location, made possible with a specially designed guide, and then classified into 3 tiers using B-mode image criteria (1) favorable, (2) questionable, and (3) unfavorable. Bone mineral density (hydroxyapatite) and BVTV were obtained from micro-CT as the gold standard.

RESULTS

Hydroxyapatite and BVTV were evaluated within the projected US slice plane and thresholded to favorable (>2200 mg/cm3; >0.45 mm3/mm3), questionable (1500-2200 mg/cm3; 0.4-0.45 mm3/mm3), and unfavorable (<1500 mg/cm3; <0.4 mm3/mm3). The present US B-mode classification inversely scales with BMD. Regression analysis showed a significant relation between US classification and BMD as well as BVTV. T-test analysis demonstrated a significant correlation between US reader scores and the gold standard. When comparing Tier 1 with the combination of Tier 2 and 3, US achieved a significant group differentiation relative to mean BMD (p = 0.004, true positive 66.7%, false positive 0%, true negative 100%, false negative 33.3%, specificity 100%, sensitivity 66.7%, receiver operating characteristics area under the curve 0.86). Similar results were found between US-derived tiers and BVTV.

CONCLUSION

Preliminary data suggest US could classify jawbone surface quality that correlates with BMD/BVTV and serve as the basis for future development of US-based socket healing evaluation after ARP.

Overview of Ultrasound in Dentistry for Advancing Research Methodology and Patient Care Quality with Emphasis on Periodontal/Peri-implant Applications

BACKGROUND

Ultrasound is a non-invasive, cross-sectional imaging technique emerging in dentistry. It is an adjunct tool for diagnosing pathologies in the oral cavity that overcomes some limitations of current methodologies, including direct clinical examination, 2D radiographs, and cone beam computerized tomography. Increasing demand for soft tissue imaging has led to continuous improvements on transducer miniaturization and spatial resolution. The aims of this study are (1) to create a comprehensive overview of the current literature of ultrasonic imaging relating to dentistry, and (2) to provide a view onto investigations with immediate, intermediate, and long-term impact in periodontology and implantology.

METHODS

A rapid literature review was performed using two broad searches conducted in the PubMed database, yielding 576 and 757 citations, respectively. A rating was established within a citation software (EndNote) using a 5-star classification. The broad search with 757 citations allowed for high sensitivity whereas the subsequent rating added specificity.

RESULTS

A critical review of the clinical applications of ultrasound in dentistry was provided with a focus on applications in periodontology and implantology. The role of ultrasound as a developing dental diagnostic tool was reviewed. Specific uses such as soft and hard tissue imaging, longitudinal monitoring, as well as anatomic and physiological evaluation were discussed.

CONCLUSIONS

Future efforts should be directed towards the transition of ultrasonography from a research tool to a clinical tool. Moreover, a dedicated effort is needed to introduce ultrasonic imaging to dental education and the dental community to ultimately improve the quality of patient care.

A comparative study of three-dimensional cone beam computed tomographic sialography and ultrasonography in the detection of non-tumoral salivary duct diseases

OBJECTIVES

To compare the overall diagnostic outcomes of 3D-CBCT sialography and ultrasonography (US) in the detection of sialolithiasis, ductal dilatation, and ductal stenosis.

METHODS

This retrospective monocentric study compared the two imaging modalities carried out in the same patients referred for salivary symptoms of the parotid and submandibular glands. The primary endpoint was the capacity of the imaging procedure to diagnose a lesion. The secondary objectives were the detection rates according to the type of lesion, analysis of the causes of failure, and the parameters of radiation exposure and safety (for 3D-CBCT sialography).

RESULTS

Of the 236 patients who received a 3D-CBCT sialography in our institution, 157 were ultimately included in the per-protocol analysis. 3D-CBCT sialography allowed detection of ductal lesions in 113 patients versus 86 with US. The two imaging modalities yielded congruent interpretations in 104 out of 157 subjects (66.2%). Higher sensitivity and negative predictive value were observed with 3D-CBCT sialography compared with US, irrespective of the lesions studied: 0.85 vs 0.65 and 0.70 vs 0.44, respectively. Regarding the sialolithiasis, both 3D-CBCT sialography and US allowed identification of lesions with high sensitivity and negative predictive value (0.80 vs 0.75 and 0.88 vs 0.78, respectively).

CONCLUSIONS

US remains the first-line examination for exploration of the salivary lesions. 3D-CBCT sialography is an alternative in case of inconclusive US, and prior to any endoscopic procedure.

Radiographic Interpretation in Oral Medicine and Hospital Dental Practice

Oral medicine practice includes the diagnosis and nonsurgical treatment of oral and orofacial diseases and oral manifestations of systemic conditions. Oral medicine specialists in medical and dental settings often require imaging in assessment and treatment of these conditions. This article reviews imaging that may be used in practice, particularly as relevant for facial pain, bone conditions, and salivary gland disease. It reviews imaging that may be considered in a hospital setting for assessment of admitted patients, patient evaluation before surgical procedures, and provision of dentistry in a hospital setting for patients who cannot submit to treatment in an outpatient setting.

Three-dimensional cone-beam computed tomographic sialography in the diagnosis and management of primary Sjögren syndrome: Report of 3 cases

Sjögren syndrome is a chronic autoimmune inflammatory disease characterized by lymphocytic infiltration of exocrine glands, predominantly the parotid and lacrimal glands, thereby resulting in oral and ocular dryness. It has been reported to occur most frequently in women between 40 and 50 years of age. Sjögren syndrome has an insidious onset, is slowly progressive, and presents a wide range of clinical manifestations, leading to delays or challenges in the diagnosis. Early diagnosis of this condition is essential to prevent the associated complications that affect patients' quality of life. This report presents 3 cases of Sjögren syndrome in female patients aged between 40 and 75 years who presented with complaints of persistent dry mouth and burning sensation. The cases highlight the diagnostic value of 3-dimensional cone-beam computed tomographic sialography in the detection of salivary gland pathologies at an early stage.

Ultrasound in the diagnosis of parotid duct obstruction not caused by sialolithiasis: diagnostic value in reference to direct visualization with sialendoscopy

OBJECTIVES

The aim of this study was to evaluate the diagnostic value of ultrasound in the obstructive pathology of the parotic gland not caused by sialolithiasis using sialendoscopy as reference standard.

METHODS

Retrospective analysis of all patients who presented with suspected diagnosis of obstructive ductal pathology of the parotid gland other than sialolithiasis between January 2011 and December 2017. 538 patients, for a total of 691 parotid glands were included in the study. Ultrasound was performed, followed by sialendoscopy in all cases. Duct diameter and parenchyma echogenicity were assessed. Direct sialendoscopic examination of the parotid duct was regarded as the reference standard.

RESULTS

Parotid glands with normal sialendoscopic findings (21.6%, n = 149) had a duct diameter of 0.3 mm (0-2.7 mm) and homogeneous hyperechoic parenchyma on ultrasound in 98.7%. Ductal inflammation/sialodochitis (32.9%, n = 227) on sialendoscopy had significantly larger ductal diameter of 0.7 mm (0-4.3 mm, p = 0.001) and hypoechoic parenchyma in 78.0% (p < 0.001). Parotid glands with stenosis (45.6%, n = 315) had hypoechoic parenchyma in 52.6% and a ductal diameter of 4.1 mm (0-19.0 mm; p = 0.001). The ductal diameter was ≥2.7 mm in 95.6% of the stenosis (AUC 0.886, p = 0.001). Using 5.1 mm as benchmark ductal diameter, stenosis with ductal anomaly (68/315) were identifiable with a sensitivity of 92.6% and a specificity of 96.8% (AUC 0.986, p = 0.001).

CONCLUSION

Ultrasound parameters can be used to distinguish different types of obstructive ductal pathology of the parotid gland, supporting the use of this imaging modality as diagnostic tool of first choice.

Ultrasound in the Assessment of Parotid Duct Stenosis

OBJECTIVES

Parotid duct stenosis may occur with or without accompanying ductal anomalies, with associated differences in their pathogenesis and management. By identifying the characteristics of a stenosis, ultrasound (US) can assist in tailored management of parotid duct stenosis. The objective of this study was therefore to describe the US characteristics of parotid duct stenoses and to evaluate criteria for whether and in what ways these can be distinguished from each other by using US.

METHODS

A total of 108 patients who presented with parotid duct stenoses (130 parotid glands) were examined with high-resolution US between 2014 and 2017. The stenoses were assessed for duct dilatation, location, signs of ductal anomalies (circular encroachments/webs, duct bending/kinking, and presence of a megaduct) and the echogenicity of the gland parenchyma.

RESULTS

Ultrasound was able to distinguish between stenoses associated with ductal anomalies and those without anomalies. Webs (82.5% versus 7.8%; P < .001), kinking (75.0% versus 3.3%; P < .001), and a megaduct (87.50% versus 15.63%; P < .001) and a tendency toward normal echogenicity in the gland parenchyma (77.5% versus 25.6%; P < .001) were significantly associated with ductal anomalies. Stenoses associated with ductal anomalies also had significantly larger duct diameters in comparison with those without anomalies (mean ± SD, 9.19 ± 3.65 versus 3.27 ± 2.17 mm; P < .001).

CONCLUSIONS

This study describes US parameters that allow more detailed characterization of parotid stenoses with or without accompanying ductal anomalies. Differentiating between these at an early stage may be helpful for decision making on the further management in these patients.

Transoral Ultrasound in the Diagnosis of Obstructive Salivary Gland Pathologies

Transcutaneous ultrasound (TCUS) is an accepted diagnostic method in salivary gland diseases. However, sparse data are available on the use of transoral ultrasound (TOUS) in sialadenopathies. One hundred five patients presenting with various obstructive sialadenopathies were examined using TOUS and TCUS. Ultrasound findings were validated by direct visualization in subsequent sialendoscopy examinations. By TOUS, but not by TCUS, all patients with sialolithiasis (70/105) could be identified and virtually all concrements, even very small ones, were detected and distinguished from artifacts. Ductal stenoses (16/105) could be correctly differentiated from sialoliths, and exceptional insights into the delicate anatomy of parotid duct stenoses were gained. TOUS provided detailed information on other space-occupying lesions (14/105) and circumvented the method-related diagnostic weaknesses of TCUS. As a valuable tool in the diagnosis of obstructive sialadenopathies, TOUS seems superior to TCUS in pathologies involving the distal parotid duct, the submandibular duct system and the floor of the mouth.

Modern management of paediatric obstructive salivary disorders: long-term clinical experience

Recent technological improvements in head and neck field have changed diagnostic and therapeutic strategies for salivary disorders. Diagnosis is now based on colour Doppler ultrasonography (US), magnetic resonance (MR) sialography and cone beam 3D computed tomography (CT), and extra- and intracorporeal lithotripsy, interventional sialendscopy and sialendoscopy-assisted surgery are used as minimally invasive, conservative procedures for functional preservation of the affected gland. We evaluated the results of our long-term experience in the management of paediatric obstructive salivary disorders. The study involved a consecutive series of 66 children (38 females) whose obstructive salivary symptoms caused by juvenile recurrent parotitis (JRP) (n = 32), stones (n = 20), ranula (n = 9) and ductal stenosis (n = 5). 45 patients underwent interventional sialendoscopy for JRP, stones and stenoses, 12 a cycle of extracorporeal shockwave lithotripsy (ESWL), three sialendoscopy-assisted transoral surgery, one drainage, six marsupialisation, and two suturing of a ranula. Three children underwent combined ESWL and interventional sialendoscopy, and seven a secondary procedure. An overall successful result was obtained in 90.9% of cases. None of the patients underwent traditional invasive sialadenectomy notwithstanding persistence of mild obstructive symptoms in six patients. No major complications were observed. Using a diagnostic work-up based on colour Doppler US, MR sialography and cone beam 3D TC, children with obstructive salivary disorders can be effectively treated in a modern minimally-invasive manner by extracorporeal and intracorporeal lithotripsy, interventional sialendoscopy and sialendoscopy-assisted transoral surgery; this approach guarantees a successful result in most patients, thus avoiding the need for invasive sialadenectomy while functionally preserving the gland.

Value of Sonography in the Diagnosis of Sialolithiasis: Comparison With the Reference Standard of Direct Stone Identification

OBJECTIVES

The aim of this study was to assess the effectiveness of sonography for diagnosing sialolithiasis in comparison with the existing reference standard of direct identification of a stone.

METHODS

A total of 659 glands with signs of obstructive sialadenopathy were evaluated retrospectively. Sonographic examinations of the large head salivary glands had been performed initially in all cases. Direct depiction of a stone during sialoendoscopy or transoral ductal surgery or observation of stone fragmentation with discharge of concrements after extracorporeal shock wave lithotripsy, was regarded as definitive evidence and as the reference standard for the presence of sialolithiasis. The sonographic results were compared with those for direct identification of stones.

RESULTS

The sensitivity of sonography was 94.7%, with specificity of 97.4%, a positive predictive value of 99.4%, and a negative predictive value of 79.6%. Stones that were not diagnosed correctly on sonography were most often located in the distal area of the duct.

CONCLUSIONS

These results show that sialolithiasis can be diagnosed by sonography with a high degree of certainty. Sonography thus appears to be highly appropriate as the examination method of choice.

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

It has been suggested that a conservative trans-oral approach to proximal and hilo-parenchymal submandibular stones (HPSMS) is a valid alternative to the more frequently used sialadenectomy. The aim of this study was to evaluate the surgical, ultrasonographic and patients' subjective outcomes of results of the trans-oral removal of HPSMS. Between January 2003 and September 2015, sialendoscope-assisted trans-oral surgery was used to remove symptomatic, large (> 7 mm), fixed and palpable HPSMS from 479 patients under general anaesthesia. All patients were followed clinically and ultrasonographically to investigate symptom relief and recurrence of stones, and were telephonically interviewed to assess saliva-related subjective outcomes with a questionnaire. Stones were successfully removed from 472 patients (98.5%); the seven failures (1.5%) concerned pure parenchymal stones. One year after the procedure, 408 patients (85.1%) were symptom free, 59 (12.3%) had recurrent obstructive symptoms and 12 (2.6%) had recurrent infections. Of the 54 patients who developed a recurrent stone (11.2%), 52 underwent a second procedure: 29 interventional sialendoscopies, two sialendoscope-assisted intra-corporeal pneumatic lithotripsy, eight secondary transoral surgery to remove residual stones, six a cycle of extra-corporeal lithotripsy and seven submandibular sialadenectomy. Most patients (75.2%) reported mild surgery-related pain. The symptoms of 454 patients (94.8%) improved after adjunctive treatment and, at the end of follow-up, the affected gland was preserved in 98.5% of patients. A sialendoscope-assisted trans-oral removal of large HPSMS is a safe, effective, conservative surgical procedure, and functional preservation of the main duct and parenchyma of the obstructed gland allows sialendoscopic access through the natural ostium in case of recurrence. Combining a trans-oral approach with other minimally invasive, conservative procedures ensures symptomatic relief and salivary duct system clearance in the majority of patients.

Three-dimensional cone-beam CT sialography in non tumour salivary pathologies: procedure and results

OBJECTIVES

Non-tumour salivary diseases are common. Imaging studies are essential for their diagnosis and before undergoing an endoscopic or surgical treatment. In this study, we aimed at presenting our procedure and results obtained with three-dimensional CBCT (3D-CBCT) sialography for non-tumour salivary gland diseases.

METHODS

Patients with parotid or submandibular salivary symptoms were examined by 3D-CBCT sialography. They received an intraductal injection of 0.5 mL of water-soluble contrast medium maintained in the gland, followed by examination in a NewTom wide-field CBCT device. Images were processed with multiplanar and 3D reconstructions.

RESULTS

A ductal exploration could be performed until the fourth divisions. The main lesions found were stones, stenosis, dilatations and "dead tree" appearance of the ductal system. No side effects of the catheterization or the iodine contrast were reported, nor tissue damages related to the contrast keeping technique.

CONCLUSIONS

3D-CBCT sialography seems to represent a reliable non-invasive diagnostic tool for ductal salivary diseases. More studies are needed to assess the value of 3D-CBCT sialography compared with conventional imaging.