Biomedical subjects

E Ariji

Publications and source records attributed to E Ariji.

At least 19 recordsLinked to original sources

PubMed2003

Computed tomography of odontogenic myxoma.

OBJECTIVES: The purpose of this study was to clarify the CT features of odontogenic myxoma. METHODS: CT appearances were analysed in 17 patients with histologically verified odontogenic myxoma collected from five dental hospitals in Japan. RESULTS: On the CT images, tumour borders were generally well defined with a smooth margin both for bony and soft tissue structures in all patients. Cortical status was clearly evaluated using CT and the continuity was interrupted in nine patients. Intralesional trabeculations were observed in 13 patients. Of these 13, 6 patients showed the characteristic appearance of angular or straight trabeculations within the tumour. The trabeculations were frequently observed at the peripheral portion of the tumour. In three maxillary tumours, soft tissue margins were observed beyond the cortical margin and/or intralesional trabeculations. In 10 of the 13 lesions evaluated, the majority of the whole tumour area showed relatively lower density compared with surrounding muscles. CONCLUSION: CT clearly demonstrated characteristic features of odontogenic myxoma. CT analysis may contribute to establishing a consensus regarding the interpretation of conventional radiographic appearances in odontogenic myxoma.

Adolescent↗

PubMed2002

Denervation atrophy of the masticatory muscles in a patient with nasopharyngeal cancer: MR examinations before and after radiotherapy.

We report on a patient with denervation atrophy of the masticatory muscles due to nasopharyngeal cancer who received therapeutic irradiation. Magnetic resonance imaging has significantly contributed to aid diagnosis of this pathology. Masticatory muscle atrophy should be a definitive finding of perineural invasion caused by head and neck tumors. Radiologists should be familiar with this appearance to avoid confusion with tumor invasion of the muscle.

Carcinoma, Squamous Cell↗

PubMed2002

Odontogenic infection pathway to the submandibular space: imaging assessment.

The aims of this study were to determine the pathways of odontogenic infection spread into the submandibular space and their relationship to the clinical symptoms. Computerized tomography (CT) and magnetic resonance (MR) images of 33 patients with submandibular involvement were analyzed. The spread of infection was evaluated by lateral asymmetry of the shape and density of the fascial spaces and tissues, and by obliteration of the interfascial fat spaces. Imaging findings were classified into three types: in 19 patients (57.6%), infection spread through the mylohyoid muscle or sublingual space (type I). In five patients (15.2%), infection spread through the bony structures of the mandible with periosteal reaction or perforation of the cortical plate (type II) and was associated with relatively mild symptoms. In four patients (12.1%), infection spread from the masticatory space (type III). Seven of 11 patients with dysphagia or fever showed submandibular involvement spreading into the parapharyngeal space. CT and MR imaging clearly demonstrated different pathways of the spread of odontogenic infection into the submandibular space, which influenced the manifestation of clinical symptoms.

Adipose Tissue↗

PubMed2002

Chronic dental infections mimicking temporomandibular disorders.

BACKGROUND: Trismus and jaw pain are not only caused by temporomandibular disorders (TMD), but also by various pathologies, namely infection, trauma, or neoplasms. TMD-like symptoms, as a result of the pathologies, may be confusing to a clinician. This paper reports two cases of chronic dental infection mimicking TMD. METHODS: Two patients were initially diagnosed with, and treated for, TMD. However the patients did not respond to the treatment. Limited range of motion and jaw pain were then clinically evaluated for differential diagnoses. Laboratory examinations and computerized tomography (CT) scans were carried out to disclose any underlying lesion. RESULTS: Laboratory examination, such as, C-reactive protein helped to detect latent infection. CT scans revealed insidious chronic dental infection imitating TMD. Surgical drainage and chemotherapy resolved the symptoms. CONCLUSION: The importance of a rational diagnostic process, including clinical and laboratory examinations and radiologic imaging, cannot be over-emphasized in elucidating true cause of the symptoms.

Aged↗

PubMed2001

Colour Doppler sonographic analysis of blood-flow velocity in the human facial artery and changes in masseter muscle thickness during low-level static contraction.

Muscle oedema, which can be seen as a thickness increment by ultrasonography, is important in provoking pain and fatigue during low-level contraction. Although oedema is related to the balance of inflow and outflow of blood, there are no data on the correlation between muscle thickness change and blood-flow. Blood-flow velocities in the facial artery and the muscle thickness changes were measured by colour Doppler ultrasonography in 30 healthy volunteers during 20 min contraction with 10% of maximum force. Thickness and velocity changes both reached a peak in the initial phase of contraction. The initial change of thickness did not correlate with the velocity in the facial artery, while those immediately after exercise showed a high correlation. The velocity changes in the facial artery might depend on both the general response to contraction and local metabolic or mechanical factors in the contracted masseters.

Adolescent↗

PubMed2001

Blood flow in and around the masseter muscle: normal and pathologic features demonstrated by color Doppler sonography.

OBJECTIVE: The purpose of this study was to clarify the normal findings of arteries in and around the masseter muscle and to present their pathologic changes with the use of color Doppler sonography. STUDY DESIGN: The vascular appearances were examined for the 4 main arteries feeding the masseter muscle in healthy volunteers (n = 38) and patients with inflammation (n = 5) and intramuscular hemangioma (n = 3). The features of these arteries were investigated together with the flow diameter, flow velocities, and arterial resistances. The symmetry indices were also calculated to assess the pathologic changes. RESULTS: The detection rates of the branch from the transverse facial artery, the masseter artery, and the branch from the maxillary or external carotid artery were 98.7%, 21.1%, and 84.2% in healthy volunteers, respectively. The facial artery that feeds the muscle from the inferior part represented 2 patterns according to anatomic variant: the masseteric branch (22.4%) and the main trunk itself (77.6%). The means of the flow diameter, maximum and minimum velocities, resistive index, and pulsatility index in healthy subjects were 1.8 mm, 24.6 cm/s, 5.1 cm/s, 0.80, and 2.51, respectively. In most of the patients with symptoms, the symmetry indices of all measurement values increased in comparison with those of healthy volunteers. CONCLUSION: Color Doppler sonography is useful in describing the arteries in and around the masseter muscle and has the potential of being used to depict the pathologic changes.

Adult↗

PubMed2001

Doppler sonography of the deep lingual artery.

PURPOSE: To clarify the Doppler sonographic features of the lingual artery in normal subjects and to evaluate those of patients with cancer of the tongue. MATERIAL AND METHODS: Sixty-seven volunteers and 12 patients with cancer and/or leukoplakia of the tongue were examined with an intraoral sonographic probe. The visibility of the deep lingual artery was determined on transverse and anteroposterior images. On the transverse images, the vascular index, which was defined as the number of colored pixels, was measured on bilateral lingual arteries. Thereafter, the degree of symmetry was evaluated for normal subjects and patients. RESULTS: In normal subjects, between younger and older volunteers, there were no significant differences in visibility of the trunk but differences were found between the two groups for the dorsal branches. The vascular indices of the right and left sides were not different. The characteristic Doppler sonographic feature was vasculature in and around the tumors in the patients with cancer of the tongue. The symmetry indices of the cancer patients were significantly different from those of normal subjects. CONCLUSION: Doppler sonography should be an important procedure for evaluation of tongue neoplasms.

Adult↗

PubMed2000

Three-dimensional computed tomographic evaluation of morphologic airway changes after mandibular setback osteotomy for prognathism.

OBJECTIVE: To observe changes in the pharyngeal airway and the hyoid bone position after mandibular setback osteotomy in 30 patients with mandibular prognathism by means of 3-dimensional computed tomography (3DCT). STUDY DESIGN: Preoperative and postoperative computed tomography (CT) examinations were performed on 17 patients treated by sagittal split ramus osteotomy with rigid osteosynthesis and on 13 patients treated by intraoral vertical ramus osteotomy without osteosynthesis. The amount of mandibular setback was measured by the preoperative to postoperative difference of the mandibular position in axial CT images. The sizes of the preoperative and postoperative pharyngeal airway were evaluated from semitransparent and crosscut 3DCT images. Postoperative displacement of the hyoid bone was evaluated by a technique to superimpose a postoperative hard tissue 3DCT image on the preoperative image. The helical scan technique was used in the CT examination. The volume rendering technique was used to create 3DCT images. RESULTS: The mean mandibular setback was 7.8 +/- 2.1 mm with a range of 5 to 11 mm. Three months after surgery, the lateral and frontal widths of the pharyngeal airway had decreased significantly in comparison with the preoperative width. The mean reduction rates of the lateral and frontal width were 23.6% and 11.4%, respectively. The diminished airway did not recover by either 6 months or 1 year after surgery in most cases. Downward and posterior displacement of the hyoid bone was seen postoperatively. There were positive correlations between the amount of mandibular setback and reduction of the lateral width of the pharyngeal airway (r = 0.54) and the amount of hyoid bone displacement (r = 0.42). There were no significant differences between the two surgical techniques. CONCLUSION: Three-dimensional computed tomography was a practical imaging technique to evaluate the morphologic airway changes. The pharyngeal airway may have irreversible narrowing after mandibular setback surgery.

Adolescent↗

PubMed2000

Can implants be correctly angulated based on surgical templates used for osseointegrated dental implants?

When placing osseointegrated dental implants, the site, angulation and depth of implants can be designed using a computed tomography (CT) or conventional X-ray tomography. To correctly identify placement pre-surgically, various kinds of surgical templates have been proposed. Although it is thought to be important to use templates, no material has been published on their accuracy. The purpose of this study was to propose a method for evaluating the placement accuracy using a specific surgical template. Twenty-one implants were evaluated in 6 patients with mean age of 50.7 years. All implants were implanted by two step surgery in the posterior mandible. A surgical template based on the CT images and the abutment replica on the working models were used for the evaluation of the accuracy of implant placement. The difference between the proposed and actual directions was measured by a milling machine. The difference in the angles between the proposed direction and actual direction were from 0.5 degrees to 14.5 degrees. The average was 5.0 degrees, and there were 12 implants (57%) within 5.0 degrees. This study demonstrated the accuracy of the template described in this article.

Dental Implantation, Endosseous↗

PubMed2000

Three-dimensional morphology of the masseter muscle in patients with mandibular prognathism.

OBJECTIVE: To compare the morphology of the masseter muscle in patients with mandibular prognathism with that of normal subjects. METHODS: Three-dimensional X-ray computed tomography (CT) was performed on 69 patients with mandibular prognathism and compared with 91 normal subjects. The angle of the muscle direction in relation to the Frankfurt horizontal plane and the area and the ratio of length of the short to long axes (s/l ratio) on the section perpendicular to the muscle direction were measured. RESULTS: The mean angle, area and s/l ratio in patients with mandibular prognathism was 76.6 degrees (s.d. 4.4 degrees), 318.3 mm2 (s.d. 77.2 mm2) and 0.312 (s.d. 0.049), respectively. Those of the normal subjects were 65.1 degrees (s.d. 4.4 degrees), 368.3 mm2 (s.d. 97.2 mm2) and 0.393 (s.d. 0.054), respectively. The angle was significantly larger, and the area and s/l ratio were significantly smaller than those of normal subjects (P < 0.001). CONCLUSION: The morphology of the masseter muscle in mandibular prognathism is significantly different from that of normal subjects. Our results may be helpful in evaluating the results of orthognathic surgery.

Adolescent↗

PubMed1999

Joint Photographic Experts Group compression of intraoral radiographs for image transmission on the World Wide Web.

OBJECTIVE: The purpose of this study was to evaluate the subjective quality of Joint Photographic Experts Group (JPEG) compressed images of intraoral radiographs with file sizes of 30 kilobytes or less, which can be transmitted quickly on the World Wide Web. STUDY DESIGN: Conventional intraoral radiographs were digitized at sampling rates of 100, 200, 300, 400, and 600 dots per inch through use of a flatbed scanner and saved in JPEG format in 11 compression degrees. Fifty-five combinations of sampling rate and compression degree were evaluated by means of a visual analog scale. Sampling rate and compression degree combinations whose quality was inferior to that of an average image were excluded. The quality of the remaining combinations was subsequently evaluated through assessment of 8 anatomical features in each image. RESULTS: Forty of the 55 combinations provided a file size less than 30 kilobytes. Thirty combinations obtained VAS scores of 0 or higher on the standardized VAS. As a result, 16 combinations of sampling and compression conditions were selected for the second part of the study. Only one combination of sampling rate and compression degree was found to provide sufficient image quality for all 8 anatomical features. CONCLUSIONS: Under the file size limit of the study design, the full-sized compressed image of an intraoral radiograph did not always provide sufficient quality. This problem will be reduced by improvements in telecommunications infrastructure, which will permit faster transfer of files of larger size.

Algorithms↗

PubMed1999

Customized mold brachytherapy for oral carcinomas through use of high-dose-rate remote afterloading apparatus.

OBJECTIVE: The aim of this study was to investigate the role of the combined use of customized molds and recently available remote afterloading brachytherapy apparatus with more flexible catheters in the treatment of superficial oral carcinomas. STUDY DESIGN: Four patients with oral squamous cell carcinoma who were treated through use of this combined technique were analyzed retrospectively. The molds were made from transparent acrylic resin through use of a dental technique. The combined approach was applied as a boost therapy after external irradiation. RESULTS: The 4 patients had had no recurrence of tumor or radiation injury by the end of the follow-up period. CONCLUSIONS: The combined technique could be an excellent method of treating superficial carcinomas of the oral cavity.

Brachytherapy↗

PubMed1999

Decreased disk-eminence ratio is associated with advanced stages of temporomandibular joint internal derangement.

OBJECTIVE: To examine the possible correlation between the stage of internal derangement and the antero-posterior length of the disk in relation to the length of the articular eminence. STUDY DESIGN: Twenty asymptomatic volunteers with normal joints and 120 patients with TMJ dysfunction underwent MR imaging. The A-P length of the disk in relation to the length of the articular eminence (D/E ratio) was measured. RESULTS: The D/E ratio was 0.95 in the asymptomatic volunteers, 0.83 in patients with disk displacement with reduction, 0.74 in those with disk displacement without reduction and 0.57 in the patients with disk displacement and osteoarthritis. The relationship between the D/E ratio and the stage of internal derangement was statistically significant (P<0.01). CONCLUSION: The D/E ratio decreases with advancing internal derangement. We suggest that it is a reliable numerical method for staging the degree of the internal derangement.

Adult↗

PubMed1998

Simple X-ray film holder for lateral view of the anterior jaws using dental X-ray apparatus.

A new X-ray apparatus, the occlusal X-ray film holder, was devised so that the lateral view of the jaw could be studied. This apparatus could easily be adjusted to a dental X-ray cone. In 21 cases of impacted teeth, cysts or foreign body in the maxilla and mandible and 6 cases that necessitated examination before or after implantation, the efficacy of this apparatus was confirmed. Its advantages are: it is applicable to dental X-ray equipment; it is cheap; there is no need for image intensifying to get a clear image; and follow-up examination is possible. We believe that this film holder would be useful for the diagnosis of lesions in the anterior maxilla and mandible as well as in the general dental clinic.

Foreign Bodies↗

PubMed1998

High-frequency color Doppler sonography of the submandibular gland: relationship between salivary secretion and blood flow.

OBJECTIVE: The purpose of this study was to evaluate the changes of blood flow of the submandibular gland in comparison with salivary secretion after gustatory stimulation through use of color Doppler sonography. STUDY DESIGN: High-frequency color Doppler sonography was performed on 30 healthy volunteers, aged 22 to 31 years. The prestimulation and poststimulation arterial blood flows were evaluated with color Doppler sonography and spectral analysis. RESULTS: The means of prestimulation maximum and minimum velocities and pulsatility index of the submandibular gland were 6.35 +/- 2.57 cm/sec, 1.79 +/- 0.93 cm/sec, and 1.53 +/- 0.42, respectively. After the stimulation, the color signals and velocities increased and the pulsatility index decreased. There was a close correlation between the increase in minimum velocity and that of salivary secretion. CONCLUSION: Color Doppler sonography is useful in analyzing changes in the blood flow of the submandibular gland caused by gustatory stimulation.

Adult↗

PubMed1998

Observer agreement in the detection of proximal caries with direct digital intraoral radiography.

OBJECTIVE: The aim of this study was to compare several values for consistency obtained by charged-coupled-device-based direct digital intraoral radiography with those obtained by conventional film-based radiography to evaluate observer agreement in determining the depth of proximal caries. STUDY DESIGN: A total of 93 proximal surfaces on radiologic images that were obtained by both the conventional film-based bite-wing technique and by direct digital intraoral radiography were evaluated by six observers. One of these observers also evaluated the same images six months after the initial evaluation. The kappa value, consistency ratio, agreement ratio, and Kendall's correlation coefficient were calculated for interobserver and intraobserver agreement. RESULTS: The overall kappa values for interobserver agreement were 0.439 and 0.424 in the direct digital system and the film-based radiography, respectively. The depth-related change of the values showed similar patterns in the two modalities for both interobserver and intraobserver agreement. CONCLUSION: The digital intraoral system resulted in no deterioration in observer agreement, and it presents no problems for clinical use with respect to the reliability of diagnosis.

Dental Caries↗

PubMed1998

Power Doppler sonography of cervical lymph nodes in patients with head and neck cancer.

PURPOSE: The purpose of this preliminary study was to evaluate the usefulness of power Doppler sonography in differentiating metastatic from nonmetastatic cervical lymph nodes in patients with cancer. METHODS: Histologically proved metastatic (n = 71) and nonmetastatic (n = 220) lymph nodes were examined with power Doppler sonography in 77 patients with head and neck cancer. Power Doppler sonography was assessed for its ability to differentiate metastatic from nonmetastatic lymph nodes. RESULTS: Power Doppler sonography showed characteristic features of parenchymal blood flow signal in 59 (83%) of the 71 metastatic lymph nodes. By contrast, only four (2%) of the 220 nonmetastatic nodes showed these power Doppler signals. In addition, power Doppler sonography showed high levels of sensitivity (83%) and specificity (98%) in depicting metastatic lymph nodes, which were superior to the values (66% sensitivity and 92% specificity) obtained by applying size criteria (transverse to longitudinal ratio). However, a combination of the two criteria (parenchymal color signal and transverse to longitudinal ratio) improved diagnostic accuracy to 92% sensitivity and 100% specificity. CONCLUSION: Our preliminary findings suggest that the power Doppler criteria of no hilar flow, peripheral parenchymal nodal flow, and a transverse to longitudinal ratio of more than 0.65 together constitute a powerful tool for depicting metastatic lymph nodes in patients with cancer.

Adult↗

PubMed1997

Computed tomography appearance of marked keratinization of metastatic cervical lymph nodes: a case report.

A case of squamous cell carcinoma of the tongue is reported with emphasis on an atypical finding of cervical lymph node metastasis visible on computed tomography. Multiple cervical lymph nodes revealed a high computed tomographic value of about 330 HU, lower than that of calcification. The lymph nodes revealed well-defined elliptical hyperechoic masses with an echogenic line and posterior shadow on ultrasonography. The appearance of a high density mass on computed tomography with a computed tomographic value lower than that of calcification may be a reliable finding of metastasis because it demonstrates the presence of marked keratinization produced by squamous cell carcinoma.

Calcinosis↗