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H Strobl

Publications and source records attributed to H Strobl.

At least 19 recordsLinked to original sources

Diagnostic quality of dynamic high-resolution ultrasonography of the TMJ--a pilot study.

The aim of this study was to compare sensitivity, specificity, accuracy and positive and negative predictive value for high-resolution ultrasonography (HR-US) in diagnosing degenerative changes, effusion and disk displacement using magnetic resonance imaging (MRI) as a reference. Over a period of 6 months, 100 patients with TMJ disorders (200 TMJs) were investigated by an experienced radiologist with HR-US and magnetic resonance imaging (MRI). The MRI investigation showed degenerative changes in 190 joints (95%), while an effusion was found in 59 (29.5%) joints. At closed-mouth position a disc dislocation was found in 138 joints (69%) and in maximum-mouth-opening position disc dislocation was diagnosed in 76 joints (38%). In the determination of degenerative changes HR-US showed a sensitivity of 94%, a specificity of 100% and an accuracy of 94%. In the detection of effusion HR-US yielded a sensitivity of 81%, a specificity of 100% and an accuracy of 95%. In the determination of disk displacement at closed-mouth position HR-US showed a sensitivity, specificity and an accuracy of 92% each. At maximum-mouth-opening position HR-US reached a sensitivity of 86%, a specificity of 91% and an accuracy of 90%. The results of the current study imply that HR-US is a valuable diagnostic imaging method of the TMJ which can be used as an alternative method to a MRI-investigation, but is yet not able to replace it. Further studies have to be done to reduce false-negative results.

False Negative Reactions↗

Effect of luxation type on pulpal blood flow measurements: a long-term follow-up of luxated permanent maxillary incisors.

Laser Doppler flowmetry (LDF) is a non-invasive method to assess pulpal blood-flow (PBF). Dental injury has been associated with significant PBF reduction. The purpose of this study was to assess whether (i) the type of luxation trauma may affect PBF measurements and (ii) whether luxation type-related measurements may show short- and long-term changes of PBF values. In 41 trauma patients, 69 maxillary incisor treated by repositioning and splinting, and the respective contralateral homologous tooth were investigated by LDF to assess local PBF values. Perfusion units were recorded in four sessions, on the day of splint removal, and 12, 24 and 36 weeks after splint removal. Statistical analysis consisted of univariate analysis of variance for repeated measurements. For the LDF measurements, the main effect of the variable 'session' was not significant (P = 0.119). However, there was a significant 'session'/'luxation type' interaction (P = 0.000). Analysis of simple session-within-luxation type effects revealed intrusive luxations to be associated with a significant decrease in PBF values (P = 0.000), while subluxations (P = 0.568), lateral luxations (P = 0.980), extrusive luxations (P = 0.910), and avulsions (P = 0.996) showed no significant difference between session-related values. The PBF measurements did not change over time for the contralateral incisors (P = 0.996). The LDF may become useful in the detection of pulpal ischaemic episodes in luxated maxillary incisors after repositioning and splinting. Further studies are warranted to assess the validity of the diagnosis of post-traumatic 'ischaemic episodes' by comparing it with histological tooth pulp changes, and by determining how well it may predict course and response to treatments in clinical trials.

Adolescent↗

[Interobserver variation of the sonographic diagnosis of orbital floor fractures and fractures of the infraorbital margin].

PURPOSE: The aim of the study was to evaluate the interobserver variation of the ultrasound diagnosis of orbital floor fractures and fractures of the infraorbital rim. MATERIAL AND METHODS: A total of 25 patients with a clinical diagnosis of an orbital trauma were investigated prospectively by computed tomography (CT) and ultrasonography (US). Inter-observer variation was calculated using the lambda coefficient (lambda). The US images were reassessed by two inexperienced investigators. RESULTS: The lambda value for the US investigation of the orbital floor showed poor reliability comparing the US findings with the results of the re-investigators. The comparison between the two re-investigators showed a good reliability for the US evaluation of the orbital floor. The lambda for the US investigation of the infraorbital margin showed a good reliability comparing the US findings with the results of the both re-investigators. The comparison of the two re-investigators showed a good reliability as well. CONCLUSION: Ultrasound is not yet an alternative method for the evaluation of orbital floor fractures and fractures of the infraorbital margin. To replace CT which is accepted as the current gold standard, further studies have to be done to reach a better diagnostic quality of the method and to achieve a better calibration of the investigations.

Adolescent↗

Laser Doppler flow investigation of fractured permanent maxillary incisors.

Laser Doppler flowmetry (LDF) is a non-invasive method to assess pulpal blood-flow (PBF). Dental injury has been associated with losses of pulpal sensibility. The purpose of this study was to assess the outcome of splint therapy on tooth fracture type-related PBF values. In 15 trauma patients, a single maxillary incisor treated by repositioning and splinting was investigated by LDF to assess local PBF values. Perfusion units were taken in four sessions, on the day of splint removel, and 12, 24 and 36 weeks after splint removal. Analysis of the tooth fracture type-related PBF measurements revealed root fractures to be associated with a significant decrease (P < 0.05) and uncomplicated crown fractures to be associated with a significant increase in PBF values (P < 0.05), while complicated crown fractures showed no significant difference between the session-related values (P > 0.05). The main findings of this study suggest splint therapy of root fractures of the central maxillary incisor to be associated with a short- and long-term decrease in PBF values. The LDF may become useful in the detection of transient ischaemic episodes and the identification of teeth at risk for adverse sequelae such as avascular necrosis and tissue loss.

Adolescent↗

The diagnostic value of ultrasonography in the detection of orbital floor fractures with a curved array transducer.

The aim of the study was to investigate the diagnostic value of ultrasonography (US) in orbital floor fractures and orbital rim fractures with a curved array scanner. Over a period of 10 months, 60 patients with an orbital trauma have been investigated. Orbital trauma was defined by clinical and ophthalmologic investigation. Computed tomography (CT) was used as the reference method to evaluate the diagnostic value of US in the determination of an orbital floor fracture and was performed by a well-experienced radiologist. Coronal and sagittal images were made. The US investigation was performed with a 7.5 MHz curved array transducer.The US investigation of the infraorbital rim showed a sensitivity of 94% and a specificity of 92% with a diagnostic accuracy of 92%. The positive predictive value (PPV) reached 91% and the negative predictive value (NPV) reached 92%, while the US investigation of the orbital floor showed a sensitivity of 95% and a specificity of 100% with a diagnostic accuracy of 98%. PPV reached 100% and NPV reached 77%. Ultrasonography is a cost-effective and widely available method without disadvantages such as radiation exposure. The results in the current study imply that ultrasonography can be used as an alternative method in the investigation of orbital floor fractures.

Adolescent↗

Laser Doppler flow measurements of pulpal blood flow and severity of dental injury.

AIM: To evaluate laser Doppler flowmetry (LDF) measurements of pulpal blood flow (PBF) and severity of dental injury. METHODOLOGY: The relationship between adverse outcomes and PBF measurements was analysed in 94 permanent maxillary incisors of 71 consecutive dental trauma patients. The diagnostic adverse outcome group was comprised of 72 incisors in 52 patients with a type I (loss of sensitivity), type II (loss of sensitivity and periapical radiolucency), or type III (loss of sensitivity, periapical radiolucency and grey discoloration of crown) diagnosis. The nonadverse outcome group consisted of 22 incisors in 19 patients with the finding of an absence of an adverse outcome. At each session, when an injured permanent maxillary incisor was recorded, a contralateral homologous tooth was used as a control. An ordinal stepwise regression was completed to assess the degree of association between PBF measurements and adverse outcomes RESULTS: Using chi-square analysis for pairwise comparison, a significant relationship between PBF measurements and types of adverse outcomes (chi(2) =119.635, d.f. = 12, P = 0.000) was observed. PBF measurements that were significantly associated with more severe outcome were PBF levels of </=3 perfusion units (PU) (119.1 odds ratio) (P = 0.000), and those of >3 PU and </=6 PU (12.7 odds ratio) (P = 0.000). CONCLUSIONS: PBF measurements were related to the severity of adverse outcomes. Further studies are required to evaluate whether PBF measurements can predict dental injuries that progress to adverse treatment outcomes.

Adolescent↗

Laser Doppler flowmetry of luxated permanent incisors: a receiver operator characteristic analysis.

Laser Doppler flowmetry (LDF) is a non-invasive method to assess pulpal blood-flow (PBF). Dental luxation injuries have been associated with significant PBF reduction. The purpose of this study was to describe diagnostic characteristics for different session-related threshold PBF values for detection of specific adverse outcomes. In 61 trauma patients, a single maxillary incisor treated by repositioning and splinting, and the respective contralateral homologous control tooth were investigated by LDF to assess local PBF values. Perfusion units (PU) were taken 12 weeks (session I) and 24 weeks (session II) after splint removal. The ability of session I-related PBF measurements at 2.8, 6.4 and 10.1 PU levels, and of session II-related ameasurements at 2.4, 6.3 and 10.2 PU levels to identify adverse outcomes occurring 36 weeks after splint removal was investigated. Adverse outcomes were classified as type I (periapical radiolucency), type II (grey discoloration), and type III (periapical radiolucency and grey discoloration of crown). Receiver operator characteristic curves were used to evaluate the sensitivity and specificity of PBF assessments. There was no significant difference in PBF values between session I and session II (P > 0.05) for teeth without an adverse outcome, and those with a type I, II or III outcome (P > 0.05). The PBF measurements did not change over time for the contralateral incisors (P > 0.05). A type I, II and III outcome occurred in 36, 21 and 12% of the incisors, respectively. The best likelihood ratio was found for the PBF 6.4 PU level at session I and incisors associated with a type I (20.8) and type II outcome (15.2). The PBV of 6.4 PU demonstrated a sensitivity of 96% and a specificity of 59% for type I outcomes, and a sensitivity of 100% and a specificity of 50% for type II outcomes. The data suggest the LDF test to be a valuable diagnostic adjunct for luxated teeth showing signs of adverse outcomes.

Adolescent↗

Diagnostic characteristics of pulpal blood flow levels associated with adverse outcomes of luxated permanent maxillary incisors.

Laser Doppler flowmetry (LDF) is a non-invasive method to assess pulpal blood flow (PBF). Dental injury has been associated with significant PBF reduction. The purpose of this study was (i) to describe PBF characteristics of teeth with specific clinical outcomes, and (ii) to demonstrate diagnostic characteristics for different threshold PBF values for detection of specific multiple adverse outcomes. In 80 trauma patients, a single maxillary incisor treated by repositioning and splinting, and the respective contralateral homologous control tooth were investigated by LDF to assess local PBF values. Perfusion units (PU) were taken in two sessions, on the day of splint removal (session I), and 12 weeks after splint removal (session II). The ability of session II-related PBF measurements at 2.9, 6.4 and 9.9 PU levels to identify adverse outcomes occurring 36 weeks after splint removal was investigated. Adverse outcomes were classified as type I (loss of sensitivity), type II (periapical radiolucency), type III (grey discolouration), type IV (loss of sensitivity and periapical radiolucency), and type V (loss of sensitivity, periapical radiolucency and grey discolouration of crown). Receiver-operator characteristic (ROC) curves were used to evaluate the sensitivity and specificity of PBF assessments. There was a significant increase in PBF values from session I to session II (P=0.0001) for teeth without an adverse outcome, while teeth affected by a type II-V outcome showed a significant decrease in PBF values (P <0.05). PBF measurements did not change over time for the contralateral incisors (P >0.05). A type IV and V outcome occurred in 21 and 24% of the instances, respectively. The PBF of 2.9 PU demonstrated a sensitivity of 70% and a specificity of 93% for type V outcomes. The best likelihood ratio was found for the PBF 2.9 PU level and incisors associated with a type V outcome. The data suggest that the LDF test to be a valuable diagnostic adjunct for luxated teeth showing signs of adverse outcomes including grey discolouration or a combination of other signs. However, it may also become necessary to apply clinical decision-making methods in order to correctly evaluate the value of information gathered. The clinical implication is that LDF may become useful in the prediction of adverse outcomes at a much earlier time period than may be accomplished by standard sensitivity tests.

Adolescent↗

[Temporomandibular disorders in juvenile patients with rheumatic diseases].

PURPOSE: The aim of the study was to investigate the incidence of temporomandibular disorders (TMD) in juvenile patients with rheumatic diseases. Furthermore, correlations between the degree of the rheumatic disease and the clinical symptoms were evaluated. MATERIAL AND METHODS: In a prospective investigation the temporomandibular joints of 48 children with rheumatic diseases were evaluated clinically regarding clicking, crepitation, pain, duration of the rheumatic disease, and the number of affected peripheral joints. The degree of rheumatic disease was assessed with Steinbrocker's classification. RESULTS: 26 patients (54.17%) showed clinical symptoms of TMD. No significant correlation was found between the degree of the rheumatic disease and the awareness of TMD. A high number of affected peripheral joints does not lead to a significant increase of TMD. A significant correlation between the duration of the rheumatic disease and TMD could be detected. A significant correlation between the duration of the rheumatic disease and clicking or crepitation was found ( p=0.011). CONCLUSION: Rheumatic diseases lead to a higher incidence of TMD in juvenile patients. A longer duration of rheumatic diseases leads to a higher incidence of TMD.

Adolescent↗

[Imaging diagnosis of medial and lateral orbital wall fractures. Sonography versus computed tomography].

PURPOSE: The purpose of the study was to evaluate the diagnostic value of a curved array scanner in the diagnosis of medial and lateral orbital wall fractures. MATERIAL AND METHODS: Fifty-three patients with the clinical diagnosis of an orbital trauma were investigated prospectively within a period of 16 months by CT and ultrasonography. The intraoperative findings were used as a reference. RESULTS: CT reached a sensitivity of 100% and a specificity of 96% in the diagnosis of medial orbital wall fractures, while ultrasound yielded a sensitivity of 80% and a specificity of 96%. There was no significant difference found between CT and ultrasonography ( p=0.402). In the investigation of lateral orbital wall fractures, CT reached a sensitivity of 88% and a specificity of 87%, while ultrasonography yielded a sensitivity of 97% and a specificity of 95%. Ultrasonography achieved significantly better results than CT ( p=0.008). CONCLUSION: The ultrasound investigation with a curved array scanner could be used as an additional method in the diagnosis of medial and lateral orbital wall fractures. Further technical improvements of the transducers need to be developed to increase the sensitivity of ultrasound in the diagnosis of medial orbital wall fractures.

Adolescent↗

The diagnostic value of ultrasonography to detect occult lymph node involvement at different levels in patients with squamous cell carcinoma in the maxillofacial region.

The purpose of this study was to evaluate ultrasonography (US) and computed tomography (CT) in detecting lymphnodes of the neck affected with squamous cell carcinoma. From 1987 to 1999 the data from 203 untreated patients with a diagnosis of cancer in the maxillofacial have been investigated. Of these, 115 had a primary squamous-cell carcinoma. US diagnosis was made by an oral- and maxillofacial surgeon experienced in US of the head and neck. CT diagnosis was made by a well-experienced radiologist. The following lymph node levels were assesed: level I (submental and submandibular lymphnodes), level II (lymphnodes distal to level I and confined to the region above the skin crease at or just below the level of the thyroid notch), level III (lymphnodes distal to level II and confined to the anterior cervical triangle including those deep to the sternocleidomastoid muscle), and level IV (lymphnodes distal to level III and confined to the posterior cervical triangle). For all levels US yielded a sensitivity of 71%, and a specificity of 87%, while CT showed a sensitivity of 32% and a specificity of 96%. The sensitivity of US decreased from level I to level IV, whereas the specificity increased from level I to level IV. For lymphnode levels I and II US may be useful for the detection of local metastases while for the other levels the application of advanced techniques of US may have to be investigated.

Carcinoma, Squamous Cell↗

[Post-traumatic ocular motility in orbital floor fractures].

PURPOSE: The aim of this study was to evaluate post-traumatic ocular motility in orbital floor fractures in relation to the severity of the fracture and concomitant injuries. MATERIAL AND METHODS: Over a period of 6 years, data from 435 patients with orbital floor fractures were re-evaluated. Ocular motility was divided into abduction, adduction, upgaze and downgaze movements. RESULTS: In 54.3% of the cases, there was a reduction in ocular motility. A reduced motility with a movement >20 degrees was found in most of the cases. Concomitant injuries to the eye resulted in a significant increase in the reduction of motility. This reduction depended on the severity of the orbital floor fracture. A reduced upgaze movement was the most common complication in all types of fractures. CONCLUSION: Ocular motility can act as an indication of the severity of the orbital fracture. Concomitant injuries to the eye resulted in a higher incidence of reduced ocular motility.

Adult↗

[Long-term outcome of dentoalveolar trauma in relation to post-traumatic instability].

PURPOSE: The aim of this retrospective study was to investigate the long-term outcomes of dental injuries. Subluxated and laterally luxated teeth were evaluated according to the findings of CO2 sensitivity, obliteration, pulpal sclerosis, and the duration of post-traumatic fixation of the injured teeth. MATERIAL AND METHODS: The data of 725 patients were analyzed retrospectively over a period of 14 years. Of these, 108 patients could be investigated for a long-term follow-up. Dental trauma was classified according to the degree of luxation (I-III). RESULTS: There was a significant correlation between the degree of luxation and the post-traumatic findings of CO2 sensitivity. There was no significant correlation between the degree of luxation and the post-traumatic findings of apical inflammation, pulpal sclerosis, and/or obliteration. Long-term fixation of injured teeth had no effect on the short- and long-term occurrence of pathologic processes at the root such as root resorption. CONCLUSION: The post-traumatic finding of CO2 sensitivity was related to the degree of luxation of the injured teeth. Apical inflammation, pulpal sclerosis, and obliteration were not related to the degree of luxation. The results suggest that long-term fixation of injured teeth has no negative effects on the long-term outcomes of subluxated and laterally luxated teeth.

Dental Pulp↗

Ligation of E-cadherin on in vitro-generated immature Langerhans-type dendritic cells inhibits their maturation.

Epithelial tissues of various organs contain immature Langerhans cell (LC)-type dendritic cells, which play key roles in immunity. LCs reside for long time periods at an immature stage in epithelia before migrating to T-cell-rich areas of regional lymph nodes to become mature interdigitating dendritic cells (DCs). LCs express the epithelial adhesion molecule E-cadherin and undergo homophilic E-cadherin adhesion with surrounding epithelial cells. Using a defined serum-free differentiation model of human CD34(+) hematopoietic progenitor cells, it was demonstrated that LCs generated in vitro in the presence of transforming growth factor beta1 (TGF-beta1) express high levels of E-cadherin and form large homotypic cell clusters. Homotypic LC clustering can be inhibited by the addition of anti-E- cadherin monoclonal antibodies (mAbs). Loss of E-cadherin adhesion of LCs by mechanical cluster disaggregation correlates with the rapid up-regulation of CD86, neo-expression of CD83, and diminished CD1a cell surface expression by LCs-specific phenotypic features of mature DCs. Antibody ligation of E-cadherin on the surfaces of immature LCs after mechanical cluster disruption strongly reduces the percentages of mature DCs. The addition of mAbs to the adhesion molecules LFA-1 or CD31 to parallel cultures similarly inhibits homotypic LC cluster formation, but, in contrast to anti-E-cadherin, these mAbs fail to inhibit DC maturation. Thus, E-cadherin engagement on immature LCs specifically inhibits the acquisition of mature DC features. E-cadherin-mediated LC maturation suppression may represent a constitutive active epithelial mechanism that prevents the uncontrolled maturation of immature LCs. (Blood. 2000;96:4276-4284)

Animals↗

Functional involvement of E-cadherin in TGF-beta 1-induced cell cluster formation of in vitro developing human Langerhans-type dendritic cells.

Epithelial Langerhans cells (LC) represent immature dendritic cells that require TGF-beta 1 stimulation for their development. Little is known about the mechanisms regulating LC generation from their precursor cells. We demonstrate here that LC development from human CD34+ hemopoietic progenitor cells in response to TGF-beta 1 costimulation (basic cytokine combination GM-CSF plus TNF-alpha, stem cell factor, and Flt3 ligand) is associated with pronounced cell cluster formation of developing LC precursor cells. This cell-clustering phenomenon requires hemopoietic progenitor cell differentiation, since it is first seen on day 4 after culture initiation of CD34+ cells. Cell cluster formation morphologically indicates progenitor cell development along the LC pathway, because parallel cultures set up in the absence of exogenous TGF-beta 1 fail to form cell clusters and predominantly give rise to monocyte, but not LC, development (CD1a-, lysozyme+, CD14+). TGF-beta 1 costimulation of CD34+ cells induces neoexpression of the homophilic adhesion molecule E-cadherin in the absence of the E-cadherin heteroligand CD103. Addition of anti-E-cadherin mAb or mAbs to any of the constitutively expressed adhesion molecule (CD99, CD31, LFA-1, or CD18) to TGF-beta 1-supplemented progenitor cell cultures inhibits LC precursor cell cluster formation, and this effect is, with the exception of anti-E-cadherin mAb, associated with inhibition of LC generation. Addition of anti-E-cadherin mAb to the culture allows cell cluster-independent generation of LC from CD34+ cells. Thus, functional E-cadherin expression and homotypic cell cluster formation represent a regular response of LC precursor cells to TGF-beta 1 stimulation, and cytoadhesive interactions may modulate LC differentiation from hemopoietic progenitor cells.

12E7 Antigen↗

Hematopoietic recovery after IEV chemotherapy for malignant lymphoma followed by different cytokines can be monitored by analysis of Galpha 16 and CD34.

The hematopoiesis-specific G protein alpha subunit Galpha16 is a specific element in the signal transduction of the early hematopoietic cytokine network. As Galpha16 mRNA can be detected in early hematopoietic progenitor cells, RT-PCR for Galpha16 can be used as a sensitive marker of hematopoietic activity. The aim of this study was to test the possible use of Galpha16 determinations for monitoring cytokine effects on hematopoietic recovery after chemotherapy in patients. We correlated presence of Galpha16 mRNA and CD34 surface antigen with hematopoietic recovery in six lymphoma patients undergoing salvage therapy with different cytokine support (IEV followed by G-CSF, IL-3, or placebo). Regardless of different cytokine schedules with different time courses, hematopoietic recovery was always preceded by transcription of Galpha16. Monitoring the expression of Galpha16 mRNA by RT-PCR is a highly sensitive diagnostic tool for analyzing hematopoietic recovery after chemotherapy and for characterizing the effects of cytokines on hematopoiesis.

Adult↗

Effect of temporomandibular joint arthrocentesis on synovial fluid mediator level of tumor necrosis factor-alpha: implications for treatment outcome.

Temporomandibular joint (TMJ) pain is a predominant sign and symptom in patients with temporomandibular disorder, and a common cause of chronic orofacial pain. Arthrocentesis of the upper joint space proved to be effective in reducing TMJ-related pain and reestablishing normal mandibular range of movement in patients diagnosed for a 'closed lock'. Using the therapeutic approach of arthrocentesis in TMJ-related instances of capsulitis/ synovitis (C/S) with a recency of first pain onset of < or =6 months, the purpose of the present study was to evaluate whether the TMJ-related variable synovial fluid (SF) level of TNF-alpha may be linked to the cessation of related signs and symptoms associated with the performance of arthrocentesis and hydraulic distension. In 23 patients with a specific temporomandibular disorder diagnosis of unilateral C/S with a recency of first pain onset of < or =6 months, TMJ SF aspirates were obtained from the pain and contralateral non-pain sides immediately before and after arthrocentesis. Visual analog scales were used for pre- and postoperative self-assessment of TMJ-related pain during function, while enzyme-linked immunosorbent assays were applied for measurement of the tumor necrosis factor-alpha (TNF-alpha) concentration. With a mean SF TNF-alpha level of 13.91 ng/ml associated with the pain side, and a mean SF TNF-alpha level of 7.73 ng/ml associated with the non-pain side, a statistically significant difference was found between the sample groups (P=0.001). Arthrocentesis led to a significant intraoperative decrease of the respective preoperative SF TNF-alpha levels, namely 61.64% (P=0.000) on the pain side and 89.50% (P=0.000) on the non-pain side, while reduction of TMJ-related pain during function was 73.17%, (P=0.000). Clinical evaluation showed a significant reduction in the prevalence of TMJ-related diagnoses of C/S (P<0.001). There was no change in the prevalence of associated TMJ-related diagnoses of internal derangement. In view of the fact that the described technique of TMJ SF analysis may be suggested as a valuable diagnostic method for the detection of biochemical SF events, the results of this study should encourage research in its potential uses so that it can become established as a reliable diagnostic approach. Further, the findings may support the concept of bilateral arthrocentesis to be effective in the treatment of patients with a unilateral specific TMD diagnosis of non-chronic C/S.

Adolescent↗

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.

Adolescent↗