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K Yonetsu

Publications and source records attributed to K Yonetsu.

17 recordsLinked to original sources
PubMed1999

Sublingual gland: MR features of normal and diseased states.

OBJECTIVE: We describe the MR features of the sublingual gland in normal and diseased states. SUBJECTS AND METHODS: We used MR imaging to assess age-related changes in size and signal intensity of normal sublingual glands in 60 control subjects. The MR features of sublingual glands were also studied in 70 patients with cancer, cellulitis of the sublingual space, Sjögren's syndrome, or ranula. RESULTS: MR imaging efficiently revealed normal sublingual glands. On T1-weighted images, the MR signal intensity of the sublingual gland was lower than that of the surrounding fat but higher than that of muscle. The sublingual glands showed age-related decreases in size, with approximately 25% of the thickness present in the second decade of life being lost by the seventh decade. T1-weighted signal intensity of the parotid gland increased with age, but the signal intensity of the sublingual and submandibular glands did not. T1-weighted signal intensity of carcinomas in and near the sublingual space was lower than that of the sublingual glands, but T2-weighted signal intensity of carcinomas exceeded that of the glands. Gadolinium enhancement occasionally diminished the contrast between invading carcinomas and the glands. T1-weighted MR imaging showed that sublingual glands affected by Sjögren's syndrome exhibit features analogous to those of the other major salivary glands; however, the sublingual glands seemed to be less severely involved overall in this syndrome than the other major glands. We found that using fat suppression and short inversion time inversion recovery may be useful for assessment of sialadenitis of the gland. CONCLUSION: MR imaging is useful in depicting normal and diseased states of the sublingual gland.

Adolescent↗
PubMed1998

Imaging findings of some buccomasseteric masses.

OBJECTIVE: The purpose of this study was to review and illustrate the appearances on diagnostic images of pathologic conditions of the buccomasseteric region. STUDY DESIGN: Computed tomographic, sonographic, and magnetic resonance images of the buccomasseteric masses were reviewed retrospectively. RESULTS: In our series of 66 cases, there were 60 benign lesions; of these, 21 were benign masses, 11 were inflammations, and 28 were myopathies. The most common pathologic condition of the buccomasseteric region was masseteric hypertrophy (n = 22). The most common lesion manifesting as a benign mass in this series was hemangioma (n = 10), which was followed by lipoma (n = 6). Six of the 66 patients had malignant tumors. CONCLUSIONS: Computed tomography and magnetic resonance imaging were useful in demonstrating the location and extent of the buccomasseteric masses. Sonography provided clear images of internal architectures of the mass in this region.

Adolescent↗
PubMed1998

Deep facial infections of odontogenic origin: CT assessment of pathways of space involvement.

PURPOSE: We investigated the pathways of spread of odontogenic infection in the facial and neck spaces. METHODS: CT scans of 45 patients with extensive spread of odontogenic infection into the facial and neck spaces were analyzed to document pathways of spread. RESULTS: Odontogenic infections arising in the mandible first spread upward, into the masseter and/or medial pterygoid muscles in the masticator space, and downward, into the sublingual and/or submandibular spaces, and then spread into the spaces or muscles adjacent to one or more of these locations. Infections from the masseter muscle spread into the parotid space to involve the temporalis and lateral pterygoid muscles. Infections from the medial pterygoid muscle spread into the parapharyngeal space to involve the lateral pterygoid muscle. Infections in the maxilla did not spread downward; instead, they tended to spread upward and superficially into the temporal and/or masseter spaces and deeply involve the lateral and/or medial pterygoid muscles in the medial masticator space. CONCLUSION: CT may be useful to depict the extent of infection and to plan treatment of extensive odontogenic infection, which can be life threatening when therapy is ineffective.

Adolescent↗
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

Idiopathic osteosclerosis of the jaws: panoramic radiographic and computed tomographic findings.

OBJECTIVE: The purpose of this study was to determine the frequency and anatomic location of idiopathic osteosclerosis in the jawbones and to present computed tomographic findings of this lesion in Japanese patients. STUDY DESIGN: Panoramic radiographs of 1047 patients were examined for the presence of idiopathic osteosclerosis in the jawbones. Computed tomography was performed in 11 patients of this series. RESULTS: A total of 64 patients (6.1%) showed this radiopacity. The highest occurrence was in the mandibular first molar region. There was no statistically significant difference in the prevalence of idiopathic osteosclerosis between males and females. On computed tomography images, these radiopaque areas were divisible into two types: enostosis (five cases) and central sclerosis (six cases). CONCLUSION: This is the first report of computed tomographic findings on idiopathic osteosclerosis in the jawbones, although the results on panoramic radiographs are similar to other investigators.

Adolescent↗
PubMed1997

Reliability of ultrasonography and sialography in the diagnosis of Sjögren's syndrome.

OBJECTIVE: The purpose of this study was to evaluate quantitatively observer performance with ultrasonography and sialography in the diagnosis of parotid gland involvement of Sjögren's syndrome. STUDY DESIGN: Sixty-four parotid gland sialograms and 65 ultrasonograms were prepared for observer performance experiments. They included both modalities in 24 Sjögren's syndrome and 19 nonspecific parotitis cases, 21 normal parotid gland sialograms, and 22 normal ultrasonograms in healthy volunteers. The images were randomly sequenced and presented to five observers who were asked to describe several findings and finally to determine the imaging diagnosis by ranking the abnormal features and the diagnosis on a five-point-rating scale. Observer performance was evaluated on the basis of the reliability of findings interpreted and the diagnostic accuracy of each modality from observers' rating scores. RESULTS: The diagnostic accuracy of sialography was very high, nearly perfect. The diagnostic accuracy of ultrasonography was lower than that of sialography, resulting from the lower incidence of characteristic findings in the disease groups and lower sensitivity on ultrasonography. In the differentiation of Sjögren's syndrome from the normal, however, the diagnostic accuracy of ultrasonography increased to 80% for all cases, and up to nearly 90% in the advanced sialographic stages. CONCLUSION: Ultrasonography is useful for the diagnosis of Sjögren's syndrome in the advanced stages. Taking the noninvasiveness of this technique into account we recommend first applying ultrasonography to the diagnosis of Sjögren's syndrome and performing sialography when no positive findings are detected on ultrasonography.

Analysis of Variance↗
PubMed1997

Imaging findings of lipomas in the orofacial region with CT, US, and MRI.

OBJECTIVE: The aim of this study was to document retrospectively the imaging findings of lipomas with the use of computed tomography, ultrasonography, and magnetic resonance imaging. STUDY DESIGN: Thirteen patients with 11 lipomas and 2 lipomatoses were evaluated. Eleven cases were examined by computed tomography, 9 by ultrasonography, and 3 by magnetic resonance imaging. RESULTS: Lipomas had a density ranging from -134 to -83 Hounsfield units, (mean-108) on the computed tomography images. The margins were ill defined in 9 of 10 cases. The superficial muscles were displaced externally in 8 cases and internally in 2 cases. With ultrasonography, 8 lesions were hypoechoic, and one was hyperechoic. All three lesions had a high signal intensity on both T1- and T2-weighted images. CONCLUSIONS: Lipomas had a specific range of computed tomography Hounsfield unit values and also displaced the surrounding soft tissue. Although some variation in the ultrasonographic appearance was observed, the lesions tended to be hypoechoic. These findings may be useful for diagnosing lipomas in the orofacial region.

Adolescent↗
PubMed1997

A remote conference system for image diagnosis on the World-Wide Web.

OBJECTIVE: The World-Wide Web on the Internet enables an exchange of multimedia information among remote desktop computers. Therefore, a teleradiology system using the Web would allow remote consultation with expert radiologists. Our objective was to establish a Web-based prototype system for image interpretation. CONCLUSION: Our system allows a physician to transmit clinically useful images to an expert radiologist at a different location, who can see them on a Web browser and discuss diagnoses with the physician.

Computer Communication Networks↗
PubMed1996

Diagnostic value of magnetic resonance imaging for malignant tumors in the oral and maxillofacial region.

The purpose of this study was to clarify the diagnostic value of magnetic resonance imaging for malignant tumors in the oral and maxillofacial region. Computed tomography and magnetic resonance images of 25 patients with malignant tumors of the oral and maxillofacial region were evaluated. Computed tomography scans were performed with intravenous contrast enhancement. A 0.2-Tesla (Hitachi Medical Corp., Tokyo, Japan) permanent magnetic resonance unit was used to obtain T1-, T2-, and proton-density-weighted images with spin-echo pulse sequences. Gadolinium-diethylene-triamine-pentaacetic acid was administered in 11 cases. Severe artifacts influencing image interpretation were observed in 10 (40%) cases on computed tomography but only in 5 (20%) cases on magnetic resonance imaging. There was no difference in the detectability of bone invasion between images from the two systems. Contrast enhancement with gadolinium-diethylene-triamine-pentaacetic acid provided additional useful information in only 3 of 11 cases compared with nonenhanced magnetic resonance images. Malignant tumors showed a higher signal intensity than that of muscle on T2-weighted images in all cases and on proton-density-weighted images in 23 (92%) cases. On T1-weighted images, an intermediate signal intensity similar to that of muscle was seen in 16 (64%) cases and a hyperintense signal in 9 (36%) cases. There was poor correlation between signal intensity and pathologic diagnosis of the tumors. These results suggest that in cases with severe artifacts that disturb the interpretation of the images on computed tomography, magnetic resonance examinations are preferable for defining the exact extent of the primary lesion.

Adult↗
PubMed1996

Quantitative analysis of the submandibular gland using computed tomography.

OBJECTIVE: To evaluate the normal variation in size of the submandibular gland from computed tomographic (CT) scans. MATERIALS AND METHODS: CT was performed parallel to the Frankfurt horizontal (FH) and mandibular (MP) planes in 130 subjects (64 men and 66 women) with healthy submandibular glands, six patients with sialoadenitis and four with masseteric hypertrophy. RESULTS: The mean (s.d.) maximum cross-sectional area (MCSA) of the submandibular glands for FH was 324 (89) mm2 and for MP 364(101) mm2. There was a high correlation between individuals' right and left glands. There was no significant difference in the mean MCSA between the right and left, which varied by less than 10%. The mean (s.d.) volume of the gland was 8072 (2574) mm3. With a high correlation with mean MCSA in both scanning planes, the mean MCSA may be an indicator of the volume of the gland. MCSA increased significantly with body height, weight and body mass index, but decreased with age. The MCSA of the affected side in patients with sialoadenitis and masseteric hypertrophy was larger than both that of the normal side and the predicted values. CONCLUSION: MCSA is a useful indicator of gland volume, and differences of greater than 10% between the two sides may be used in the diagnosis of submandibular gland disease.

Adult↗
PubMed1994

Central squamous cell carcinoma of the mandible. Computed tomographic findings.

Five cases of central squamous cell carcinoma of the mandible were investigated with the use of computed tomography. Bucco-lingual extent and spread along the mandibular division of the trigeminal nerve were evaluated. Three patients with trismus showed involvement of the masseter or medial pterygoid muscle on computed tomography. Involvement of more than two landmarks along the trigeminal nerve were observed in cases with both paresthesia of the lower lip and severe pain that resembled neuralgia. Perineural invasion was confirmed histologically in four cases, and all of these patients had both severe pain and mandibular canal involvement that could be demonstrated with computed tomography. When localized soft tissue changes are evident along the course of the trigeminal nerve in the region between the mandibular foramen and foramen ovale, ascending perineural spread should be suspected. Computed tomography findings correlated well with clinical symptoms but added information about the spread of the lesion within the surrounding soft tissue.

Carcinoma, Squamous Cell↗
PubMed1993

Magnetic resonance imaging of oral and maxillofacial angiomas.

Eleven patients with oral and maxillofacial angiomas (seven hemangiomas and four lymphangiomas) were evaluated with magnetic resonance imaging using a 0.2-T permanent system and spin-echo pulse sequences. These lesions typically had signal intensities that were iso T1-weighted, similar to muscle, and high T2-weighted, greater than subcutaneous fat. Nine tumors had well- or relatively well-defined margins, and seven cases had curvilinear structures of low signal intensities in the masses on T2-weighted images. It was impossible to distinguish hemangiomas from lymphangiomas on MR images. Our experience suggested that most angiomas of oral and maxillofacial regions present special characteristics on magnetic resonance images. It is thought that information obtained with magnetic resonance images can contribute significantly to the evaluation of the extent of these lesions.

Adolescent↗
PubMed1993

Computed tomography of the jaws in familial adenomatosis coli.

Familial adenomatosis coli is known to be associated with tooth impactions, odontomas, and osteomas. Three cases were examined by panoramic radiography and computed tomography. Computed tomography was especially useful for detecting osteomas in the maxilla and also revealed a wavy cortical thickening in the mandible in one instance. The latter finding has been reported for other bones in the body but not previously for the mandible.

Child↗
PubMed1993

Analysis of maxillary sinusitis using computed tomography.

Odontogenic maxillary sinusitis can be defined as sinusitis induced by a dental lesion. We examined the CT findings of 68 patients with maxillary sinusitis in order to differentiate between inflammation of sinus origin and inflammation of dental origin. Maxillary sinusitis was classified into four types according to clinical symptoms, history and conventional radiographic findings: type 1, simple sinusitis; type 2, odontogenic sinusitis; type 3, mixed sinusitis; type 4, slight sinus abnormality with a dental lesion. The relationship between the type of maxillary sinusitis and CT findings was analysed. Type 1 sinusitis exhibited severe pathological changes in both mucosa and bone which often extended into the nasal cavity and other paranasal sinuses. Type 2 sinusitis exhibited localized pathology on the unilateral antral floor. Type 3 sinusitis exhibited severe pathology characteristic of type 1 combined with type 2 sinusitis. Type 4 sinusitis could be differentiated by the CT findings into type 1 or type 2 sinusitis. The classification of sinusitis in this manner has implications for treatment planning, and CT should therefore be performed when conventional radiography does not provide sufficient information.

Female↗
PubMed1991

Salivary SPECT and factor analysis in Sjögren's syndrome.

Salivary SPECT and factor analysis in Sjögren's syndrome were performed in 17 patients and 6 volunteers as controls. The ability of SPECT to detect small differences in the level of uptake can be used to separate glands from background even when uptake is reduced as in the patients with Sjögren's syndrome. In control and probable Sjögren's syndrome groups the uptake ratio of the submandibular gland to parotid gland on salivary SPECT (S/P ratio) was less than 1.0. However, in the definite Sjögren's syndrome group, the ratio was more than 1.0. Moreover, the ratio in all patients with sialectasia, which is characteristic of Sjögren's syndrome, was more than 1.0. Salivary factor analysis of normal parotid glands showed slowly increasing patterns of uptake and normal submandibular glands had rapidly increasing patterns of uptake. However, in the definite Sjögren's syndrome group, the factor analysis patterns were altered, with slowly increasing patterns dominating both in the parotid and submandibular glands. These results suggest that the S/P ratio in salivary SPECT and salivary factor analysis provide additional radiologic criteria in diagnosing Sjögren's syndrome.

Adult↗
PubMedDate not supplied

Ultrasonographic study of the relation of metastatic nodes to the carotid artery.

Ultrasonographic studies of the neck were performed in four patients with metastatic lymph nodes that exhibited limited mobility or fixation to the surrounding tissues on palpation to obtain information about the relationship of nodes to the carotid artery. Comparison of the ultrasonograms with the operative findings disclosed that when a metastatic lymph node adhered to the carotid artery, the lymph node pulsated with flattening of the carotid artery and the echoes between the metastatic lymph node and carotid artery were attenuated.

Aged↗