Stefan Bertram

The diagnostic value of ultrasonography to determine the temporomandibular joint disk position

OBJECTIVE Temporomandibular joint (TMJ) arthrography and magnetic resonance imaging are the imaging techniques of choice in patients presenting with signs and symptoms of TMJ disorders suggesting soft tissue pathosis. With the disadvantage of arthrography as an invasive procedure and magnetic resonance imaging posing a problem in clinical availability and cost, the purpose of this study was to determine whether ultrasonography could be used to assess the presence or absence of disk displacement in patients with TMJ disorders. STUDY DESIGN In 17 patients, 100 TMJ positions were investigated by static and dynamic ultrasonography to analyze the disk-condyle relationship. To compare the respective findings with those of a diagnostic method offering high accuracy, coronal and sagittal magnetic resonance imaging was carried out immediately afterwards. RESULTS With static ultrasonography showing a sensitivity of 0.41 and a specificity of 0.70 and dynamic ultrasonography a sensitivity of 0.31 and a specificity of 0.95, the data revealed that static and dynamic ultrasonography are marginal in detecting the presence of disk displacement, but dynamic ultrasonography is sensitive in detecting the absence of disk displacement. However, with a positive predictive value of 0.61 and a negative predictive value of 0.51 for static ultrasonography, and a positive predictive value of 0.88 and a negative predictive value of 0.55 for the dynamic technique, the results indicate that both modalities are insufficient in establishing a correct diagnosis for the presence or absence of disk displacement. CONCLUSION In view of the fact that dynamic ultrasonography proved to be a reliable diagnostic aid for the detection of normal disk position, the results of this study should be of further interest and encourage research in its potential uses and diagnostic capabilities.

Clinically important difference thresholds of the visual analog scale: A conceptual model for identifying meaningful intraindividual changes for pain intensity

Summary A range of clinically important difference values is provided according to the patients’ baseline pain severity and duration of pain. Abstract The aim of this study was to estimate a range of clinically important difference (CID) values of the visual analog scale for pain intensity (VAS‐PI), and to assess the effect of patient baseline characteristics on VAS change scores. Data from a prospective cohort study with 678 patients with subacute and chronic temporomandibular disorder pain were analyzed. Patients were divided into 9 cohorts on the basis of the baseline VAS score and the duration of pain. The CID was estimated over a 12‐week period, and 2 different methods were used: (1) mean change scores, and (2) optimal cutoff point in receiver operator characteristic curves. The patients global impression of change was used as an external criterion. The general linear model univariate analysis was applied to assess the effect of baseline pain level and duration of pain on the raw VAS change scores, while adjusting for age and sex. The CID mean change ranged from 20.9 to 57.5 mm (64.1–76.3%), and the CID optimal cutoff point from 11.5 to 28.5 mm (29.9–47.7%). For the VAS change scores, the main effect of the variable baseline pain level was significant (F = 107.09, P < .001). However, there was no significant baseline pain level by duration of pain interaction effect (F = 1.13, P = .340). On the basis of the results, we advocate the choice of a single CID value according to the context of the patients baseline level of pain.

Ultrasonographic cross-sectional characteristics of muscles of the head and neck

OBJECTIVE Computed tomography and magnetic resonance imaging are the common techniques for evaluating cross-sectional areas and volumes of human jaw muscles. Because computed tomography has the disadvantage of showing cumulative biological effects and because MRI poses a problem in terms of clinical availability and cost, the purpose of this study was to determine whether ultrasonography could be used to measure local linear cross-sectional dimensions of muscles of the head and neck. STUDY DESIGN In 46 patients with signs and symptoms of temporomandibular disorders, the anterior temporalis, anterior masseter, deep masseter, anterior digastric, posterior digastric, and sternocleidomastoid muscles were measured bilaterally by ultrasonography to assess linear local cross-sectional dimensions. Measurements were made in 2 sessions with a time interval of at least 5 minutes. Data were analyzed for reliability and variability through use of the intraclass correlation coefficient (ICC) and the repeatability coefficient (RC). To assess local muscle asymmetry patterns, the absolute asymmetry index was used, with the mean maximum muscle diameters of the respective right and left sides calculated from 3 consecutive measurements. RESULTS Satisfactory visualization of muscles was obtained in 93.8% of 1104 imaging procedures. For the ultrasound measurements there was a significant difference in local cross-sectional dimensions between the first and second sessions for the anterior temporalis muscle only (P < .01). Acceptable intrarater reliabilities were obtained for the deep masseter (ICC = 0.92), anterior digastric (ICC = 0.91), and sternocleidomastoid (ICC = 0.86) muscles, whereas evaluation of the posterior digastric (ICC = 0.74), anterior masseter (ICC = 0.72), and anterior temporalis (ICC = 0.70) muscles was associated with moderate reliability. Variability of repeated measurements was found to be acceptable for the anterior temporalis (RC = 0.32 mm) and posterior digastric (RC = 0.48 mm) muscles. Analysis of muscle site-related local cross-sectional dimensions showed a significant difference between the right and left sides for the deep masseter muscle only (P < .05). The study population investigated revealed mean asymmetry indices ranging from 5.3% for the anterior digastric muscle to 8.7% for the deep masseter muscle. CONCLUSIONS Ultrasonography may prove to be a reliable diagnostic technique for the evaluation of cross-sectional dimensions and areas of muscles of the head and neck.

Ultrasonographic anatomy of the anterior neck: implications for tracheostomy.

PURPOSE Tracheostomy is the preferred intervention for surgical establishment of an upper airway in the treatment of certain elective maxillofacial procedures. Complication rates associated with surgical tracheostomy are largely related to the restricted possibilities in diagnosis of anatomic variations. Therefore, endoscopic-guided tracheostomy is increasingly being used to enhance precision and safety. The purpose of this study was to assess the ultrasonographic anatomy of the anterior neck with regard to the performance of tracheostomy. PATIENTS AND METHODS Fifty patients underwent ultrasonographic investigation to analyze the relationship of anatomic structures lying in the immediate vicinity of the tracheostomy site. RESULTS The data presented demonstrate the feasibility and advantage of preoperative ultrasonography to visualize the structures of the infrahyoid region. CONCLUSION Preoperative ultrasonography may be of great importance in diagnosing individual anatomic variations at the site of tracheostomy and in avoiding complications.

Structural Characteristics of Bilateral Temporomandibular Joint Disc Displacement Without Reduction and Osteoarthrosis Are Important Determinants of Horizontal Mandibular and Vertical Ramus Deficiency: A Magnetic Resonance Imaging Study

PURPOSE To estimate in patients with temporomandibular joint (TMJ) arthralgia whether magnetic resonance (MR) imaging findings of bilateral TMJ disc displacement without reduction (DDwoR) and/or osteoarthrosis (OA) are determinants of horizontal mandibular and vertical ramus deficiencies. PATIENTS AND METHODS Bilateral MR imaging of the TMJ was performed in 68 consecutive patients with TMJ arthralgia to identify those with bilateral TMJ DDwoR and/or OA. Linear and angular cephalometric measurements were performed to apply selected criteria of horizontal mandibular (gonion-menton [Go-Me] <73 mm and articulare-pogonion [Ar-Pog] <105 mm) and vertical ramus (articulare-gonion [Ar-Go] <45 mm) deficiencies. Logistic regression analysis was used to estimate the association between selected MR imaging and cephalometric parameters. RESULTS In the age- and gender-adjusted analysis, significant increases in the risk of horizontal mandibular (odds ratio, 7.5:1; P = .031) and vertical ramus (odds ratio, 9.5:1; P = .003) deficiencies occurred with bilateral DDwoR and OA. CONCLUSION In patients with TMJ arthralgia, the MR imaging parameters of DDwoR and OA seem important determinants of horizontal mandibular and vertical ramus deficiencies.

The ultrasonic value of local muscle hypertrophy in patients with temporomandibular joint disorders

Muscle pain and tenderness on palpation are two common symptoms in patients with temporomandibular joint disorders. Examination of the masticatory muscles is largely restricted to the use of electromyography. The technique of ultrasonography in the diagnosis of muscle hypertrophy in patients with temporomandibular joint disorders was investigated. The results of the study indicate that ultrasonography may be beneficial to locate affected muscles that do not exhibit symptoms of tenderness on palpation and thereby give hints for treatment planning.

Topographic variations in anatomical structures of the anterior neck of childrenAn ultrasonographic study

OBJECTIVE Tracheostomies in children are frequently used for temporary airway support during surgical procedures. In pediatric patients with congenital craniofacial malformations, preoperative assessment of the delicate anatomy of the airway is necessary. The purpose of this study was to assess the ultrasonographic anatomy of the anterior neck with regard to the performance of tracheostomy. STUDY DESIGN Ultrasonographic investigation was done in 50 pediatric patients (age range, 6 to 15 years) to analyze the relationships among the anatomical structures that are of practical interest with respect to tracheostomy. RESULTS The data reveal that information concerning variations in anatomical structures lying in the immediate vicinity of the tracheostomy site was readily obtainable with the techniques used. CONCLUSIONS In pediatric patients requiring tracheostomy for surgical treatment of severe congenital craniofacial malformations, preoperative ultrasonography may be used to diagnose individual anatomical variations at the tracheostomy site.

Assessment of Location of the Mandibular Canal: Correlation Between Panoramic and Cone Beam Computed Tomography Measurements

PURPOSE To compare panoramic and cone beam computed tomography (CBCT) determinations of implant-to-mandibular canal (MC) dimensions in mandibular regions posterior to the mental foramen and to investigate whether factors such as gender, age, region, and vertical dimension influence correlation between the two techniques. MATERIALS AND METHODS A retrospective analysis was carried out in 64 consecutive adult patients (42 females, 22 males; average age 57.1 ± 13.3 years) in whom 126 implants were positioned in the posterior segment of the mandible. Implant sites (first premolar, second premolar, first molar, and second molar) were assessed on each panoramic and CBCT radiograph by measuring the distance from the inferior border of the implant to the superior border of the MC. Binary logistic regression analysis was used to compute the odds ratios (ORs) of each implant site for underestimation vs nonunderestimation. Linear regression analysis was performed with CBCT dimension as the dependent variable and panoramic dimension, gender, and age as the independent variables. RESULTS The mean implant-to-MC dimension was 2.50 ± 1.31 mm in panoramic radiography and 2.91 ± 1.62 mm in CBCT. The OR that an implant at the second molar region belonged to the underestimation group was strong (15.1:1) and highly significant (P = .011). If a predictive value of .95 was demanded, the implant-to-MC dimensions had to be overestimated by 2 mm compared to the predicted CBCT dimension. CONCLUSION This study provides evidence of an underestimation of available vertical bone dimensions for implants in the posterior regions of the mandible when assessed by panoramic radiography. Use of CBCT is therefore recommended for all implant size estimations in this region.