Biomedical subjects
Publications and source records attributed to Misa Sumi.
OBJECTIVE: A balanced turbo field-echo (FE) sequence is a balanced steady-state free precession sequence used for achieving rapid and high imaging. We tested whether this imaging technique is applicable to the diagnosis of parotid gland diseases. CONCLUSION: The balanced turbo FE sequence is a novel alternative MRI technique for the diagnosis of various parotid gland diseases.
OBJECTIVE: We evaluated the diagnostic criteria of high-resolution MRI in differentiating benign and malignant cervical nodes that were palpable and superficial in the neck. SUBJECTS AND METHODS: We performed MR microimaging on 24 histologically proven metastatic nodes, 14 histologically proven lymphomas, and 35 histologically or clinically proven benign nodes in the necks of 26 patients. The lymph nodes were imaged with T1-weighted spin-echo, fat-suppressed T2-weighted turbo spin-echo, and spin-echo diffusion-weighted echo-planar sequences using a 47-mm microscopy coil. RESULTS: MR microimaging provided high-resolution images of the nodes. Hilar fat was lost in 92%, 79%, and 46% of the metastatic nodes, lymphomas, and benign nodes, respectively. Smooth nodal margins were lost in 58%, 23%, and 9% of metastatic nodes, lymphomas, and benign nodes, respectively. Heterogeneous nodal parenchyma on T1- or fat-suppressed T2-weighted images, or both, was observed in 88%, 29%, and 23% of metastatic nodes, lymphomas, and benign nodes, respectively. The apparent diffusion coefficients were significantly different among these three node groups (p < 0.001), with metastatic nodes being the highest, followed by benign nodes. Logistic regression analyses showed that heterogeneous nodal parenchyma and apparent diffusion coefficient levels were significant in discriminating metastatic nodes, and apparent diffusion coefficient levels in discriminating lymphomas. Combined use of these MR microscopic criteria on nodal architecture and apparent diffusion coefficients yielded 90% accuracy (86% sensitivity, 94% specificity) and 93% accuracy (85% sensitivity, 95% specificity) for discriminating metastatic nodes and lymphomas, respectively. CONCLUSION: The nodal architecture and apparent diffusion coefficient levels on MR microimaging may provide useful information in diagnosing benign and malignant nodes in the neck.
PURPOSE: To establish a fast and high-resolution MR sialographic technique that provides fast and high-resolution imaging. MATERIALS AND METHODS: MR sialography was performed on a 1.5-T MR imager using a small (47-mm) surface coil. We determined appropriate sequence parameters, and then applied the technique to the salivary glands of 143 patients with xerostomia (including those with Sjögren's syndrome or hyperlipidemia) or salivary gland inflammation. We compared the high-resolution MR sialography with conventional x-ray sialography in the patients with xerostomia to evaluate the effectiveness of the MR sialography technique. RESULTS: We found that a single-shot, single-slice MR sialography (TR/TR/number of signal acquisitions [NSA] = 8000 msec/1000 msec/6) using a small surface coil provides excellent duct images that are clinically feasible with fast (imaging time of 56 seconds) and high-resolution images. An alternative three-dimensional MR sialography technique provided better details of the branches at the expense of imaging time. The MR sialography technique using a small surface coil depicted effectively the ductal changes in the salivary glands in patients with or without Sjögren's syndrome, reflecting the severity of the diseases. CONCLUSION: We conclude that MR sialography can be performed using a fast and high-resolution sequence.
OBJECTIVE: The purpose of this study was to detect quantitative diffusion-weighted abnormalities in the lacrimal glands of patients with Sjogren's syndrome. MATERIALS AND METHODS: Diffusion-weighted MRI was performed on 31 healthy volunteers and 11 Sjogren's syndrome patients with impaired lacrimal function. The volunteers and patients underwent MRI with a single-shot spin-echo echo-planar technique using a 47-mm microscopy coil. The apparent diffusion coefficient (ADC) of the lacrimal and parotid glands was obtained with b factors of 500 and 1,000 sec/mm(2). T1-weighted and fat-suppressed T2-weighted MR microscopic images were also obtained to evaluate the gland morphology and signals. RESULTS: MR microscopy provided high-resolution images of the lacrimal glands that enabled ADC measurements. The ADCs of the normal lacrimal glands showed no significant sex- or age-related changes. The ADCs for the lacrimal glands were significantly higher than those of the parotid glands in the same subjects (mean +/- SD, 891 +/- 103 vs 703 +/- 84 x 10(-6) mm(2)/sec, respectively; p < 0.0001, Mann-Whitney U test). We found that ADCs of the lacrimal glands in Sjogren's syndrome patients were significantly lower than those from the normal glands of age-matched healthy volunteers (736 +/- 34 vs 923 +/- 84 x 10(-6) mm(2)/sec; p < 0.0001, Mann-Whitney U test). CONCLUSION: These findings suggest that the measurement of ADCs may be a useful tool to assess abnormalities of the lacrimal glands in patients with Sjogren's syndrome.
BACKGROUND AND PURPOSE: MR imaging of the salivary glands has been applied to the diagnosis of Sjogren's syndrome; however, the diagnosis remains qualitative. We sought to establish and evaluate quantitative MR imaging criteria for the diagnosis of Sjogren's syndrome. METHODS: MR imaging with a 47-mm microscopy coil was performed in 83 patients with xerostomia (55 patients with Sjogren's syndrome, 28 without Sjogren's syndrome). MR images were obtained by T1-weighted and fat-suppressed T2-weighted imaging and by MR sialography of the parotid glands. MR imaging findings of the parotid glands in Sjogren's syndome included increases in fat areas and decreases in intact lobule areas. These MR images were morphometrically analyzed for the diagnostic criteria. RESULTS: MR imaging with a microscopy coil demonstrated well the details of the damaged parotid glands in patients with xerostomia. Quantitative MR imaging of fat, intact gland lobule, and number of sialoectatic foci significantly and highly correlated with severity of disease. Receiver operating characteristic (ROC) curve analysis demonstrated that quantitative MR imaging yielded high diagnostic ability in differentiating patients with xerostomia who have Sjogren's syndrome from those without Sjogren's syndrome, with areas under the ROC curve of 0.94 for fat area, 0.98 for intact lobule area, and 0.91 for number of sialoectatic foci. The best cutoff points by quantitative MR imaging were each associated with high sensitivity and specificity, and, when used in combination, yielded 96% sensitivity and 100% specificity. CONCLUSION: Quantitative MR imaging effectively differentiated the parotid glands in patients with xerostomia who have Sjogren's syndrome from those without the syndrome and provided criteria for staging the gland disease.
BACKGROUND AND PURPOSE: The size of the primary lesion and the lymph node metastasis are critical indicators for the patient prognosis. Here we attempted to assess the correlation between these 2 prognostic parameters in patients with oropharyngeal, hypopharyngeal, oral, or maxillary sinus cancer. METHODS: We retrospectively studied 66 patients with oropharyngeal or hypopharyngeal (n = 24), oral (n = 35), or maxillary sinus (n = 7) cancer. Of these patients, 25 (10 with oral or maxillary sinus and 15 with pharyngeal cancers) had lymph node metastases. We measured the volumes of the primary lesions as sums of gadolinium-enhanced areas on fat-suppressed, spectral presaturation with inversion recovery (SPIR) T1-weighted images. Histologically confirmed metastatic nodes were mapped to the neck levels. RESULTS: The tumor volumes were well correlated with the clinical T-category for the primary lesions in oral, maxillary sinus, and oropharyngeal and hypopharyngeal cancers. The volumes of the oropharyngeal and hypopharyngeal cancers were significantly greater (P < .05) in patients with metastatic nodes than in patients without metastasis, whereas there was no significant correlation between the tumor volume and nodal metastasis in patients with oral or maxillary sinus cancer (Mann-Whitney U test). Furthermore, the correlation between tumor volume and the distribution of metastatic nodes in the neck was observed to be weak in patients with oral or maxillary sinus cancer. CONCLUSION: The MR image-based tumor volume measurement proved to be clinically feasible. We observed a good correlation between tumor volume and lymph node metastasis in patients with oropharyngeal or hypopharyngeal cancer but not in those with oral or maxillary sinus cancer.
We evaluated 9.4-T magnetic resonance (MR) microimaging in assessing normal and defective bone development in mouse embryos. For this purpose, we performed 9.4-T MR microimaging on developing bones in normal embryos, and also in Runx2/Cbfa1-/- embryos with severely defective bone development. MR images were compared with the histological and histochemical features of these fetal bones. MR microimaging delineate successfully the normal long bone development in embryos. The T1- and T2-weighted MR microimaging demonstrated chondrocyte maturation in different regions of growing cartilage, such as epiphysis, physis, hypertrophic cartilage, and zone of provisional calcification. These developmental changes were detectable in as early as E14.5 embryos. The MR microimaging clearly demonstrated defective bone development in Runx2/Cbfa1-/- embryos. The femur from E18.5 homozygous Runx2/Cbfa1-/- embryos lacked MR signal intensity patterns including the hypertrophic cartilage, which are characteristic of the bone from the age-matched Runx2/Cbfa1+/+ embryos. Interestingly, however, the tibia from the same mutants was associated with MR signal patterns indicative of hypertrophic cartilage but not of the primary spongiosa and ossifying perichondrium, suggesting that bone development is differently regulated in these two long bones. On the other hand, the bones from heterozygous Runx2/Cbfa1+/- embryos exhibited an MR phenotype intermediate between the Runx2/Cbfa1+/+ and Runx2/Cbfa1-/- embryos; the primary spongiosa and ossifying perichondrium formation occurred normally even in the absence of preceding organized maturation of chondrocytes, a phenotype that was not detected by histological examinations. We concluded that MR microimaging is useful in assessing the bone development.
We asked in this study if the quantitative sonographic analysis could diagnose effectively the benign and malignant tumors of the parotid gland. Sonographic analyses using mean grey values and SDs of echo levels were performed on the 21 benign tumors and 22 malignant tumors of the parotid glands. Both the mean grey level and the SD of the echo levels were significantly and characteristically different among the different parotid tumor groups. Discrimination analysis showed that, compared with single uses, a combined use of these two criteria improved diagnostic accuracy to 81% (carcinoma vs. pleomorphic adenomas), 93% (malignant lymphomas vs. pleomorphic adenomas), 91% (carcinomas vs. malignant lymphomas), 100% (pleomorphic adenomas vs. Warthin's tumors), 100% (carcinomas vs. Warthin's tumors) and 100% (malignant lymphomas vs. Warthin's tumors). These findings suggest that quantitative sonographic analysis is effective in differentiating benign and malignant tumors of the parotid gland.
BACKGROUND AND PURPOSE: Correctly diagnosing metastatic nodes is important for the follow-up of patients with clinical N0 stage neck disease and oral cancer. A combination of helical CT and Doppler sonography may facilitate the accurate detection of lymph node metastasis in patients with clinical N0 stage neck disease. METHODS: A combination of contrast-enhanced helical CT and Doppler sonography was performed to monitor the necks of 58 patients with initial clinical N0 stage neck disease. Of these patients, 17 underwent surgery; nodal metastasis in the neck was histopathologically confirmed. A node was diagnosed as metastatic if it fulfilled the CT criteria for metastatic nodes (short-axis diameter equal to or greater than the cutoff points for each level of the neck or central nodal necrosis) and if, additionally, it did not exhibit sonographic features for nonmetastatic nodes (normal hilar echogenicity and hilar flows). The presence of metastasis was confirmed histopathologically. RESULTS: During the follow-up periods, metastatic nodes were histologically confirmed in 17 (29%) patients. Of 30 metastatic nodes from the 17 patients with metastatic nodes, 22 (73%) appeared within the first year and 28 (93%) within the first 2 years; 20 developed from nonmetastatic nodes, and 10 were newly detectable. The combined criteria were effective in revealing 26 (87%) nodes, yielding 87% sensitivity, 100% specificity, and 100% positive and 99% negative predictive values. The independent use of one of these techniques alone resulted in low (67%) or moderate (87%) positive predictive values for sonography and CT, respectively. Seven hundred forty-one (97%) of 761 nodes that were nonmetastatic at initial examination remained nonmetastatic (737 nodes) or had disappeared (four nodes). As a result, a combination of CT and sonography was effective in revealing all 17 cases of metastatic nodes. CONCLUSION: A combination of contrast-enhanced helical CT and Doppler sonography is useful for the follow-up study of clinical N0 stage neck disease.
BACKGROUND AND PURPOSE: Metastasis to the regional cervical lymph nodes may be associated with alterations in water diffusivity and microcirculation of the node. We tested whether diffusion-weighted MR imaging could discriminate metastatic nodes. METHODS: Diffusion-weighted echo-planar and T1- and T2-weighted MR imaging sequences were performed on histologically proved metastatic cervical lymph nodes (25 nodes), benign lymphadenopathy (25 nodes), and nodal lymphomas (five nodes). The apparent diffusion coefficient (ADC) was calculated by using two b factors (500 and 1000 s/mm(2)). RESULTS: The ADC was significantly greater in metastatic lymph nodes (0.410 +/- 0.105 x 10(-3) mm(2)/s, P <.01) than in benign lymphadenopathy (0.302 +/- 0.062 x 10(-3) mm(2)/s). Nodal lymphomas showed even lower levels of the ADC (0.223 +/- 0.056 x 10(-3) mm(2)/s). ADC criteria for metastatic nodes (>/= 0.400 x 10(-3) mm(2)/s) yielded a moderate negative predictive value (71%) and high positive predictive value (93%). Receiver operating characteristic analysis demonstrated that the criteria of abnormal signal intensity on T1- or T2-weighted images (A(z) = 0.8437 +/- 0.0230) and ADC (A(z) = 0.8440 +/- 0.0538) provided similar levels of diagnostic ability in differentiating metastatic nodes. The ADC from metastatic nodes from highly or moderately differentiated cancers (0.440 +/- 0.020 x 10(-3) mm(2)/s, P <.01) was significantly greater than that from poorly differentiated cancers (0.356 +/- 0.042 x 10(-3) mm(2)/s). CONCLUSION: Diffusion-weighted imaging is useful in discriminating metastatic nodes.
OBJECTIVE: We determined the apparent diffusion coefficients of normal and dysfunctional salivary glands. SUBJECTS AND METHODS: A diffusion-weighted single-shot spin-echo type of echoplanar MR imaging was performed on the parotid or submandibular glands, or both, in 36 healthy subjects, 20 patients with Sjögren's syndrome, and six patients with sialoadenitis. The apparent diffusion coefficient of the salivary gland was calculated using two b factors (b = 500 and 1,000 sec/mm(2)). RESULTS: The apparent diffusion coefficient was lower in the parotid glands (0.28 x 10(-3) mm(2)/sec) than that of the submandibular glands (0.37 x 10(-3) mm(2)/sec). The apparent diffusion coefficient was increased in sialoadenitis, whereas it decreased with abscess formation. The apparent diffusion coefficients of the parotid glands in patients with Sjögren's syndrome correlated with the salivary flow rates but not with the sialographic gradings of the glands. We also found a correlation of the decreases in apparent diffusion coefficients with the severity of gland damage as assessed on T1-weighted MR images. CONCLUSION: Diffusion-weighted echoplanar MR imaging may reveal diseased states of the salivary glands.
BACKGROUND AND PURPOSE: CT and MR imaging are useful for evaluating the extension of carcinomas in the face and neck. We evaluated the involvement by carcinoma arising from the gingiva (ie, gingival cancer) by using CT and MR imaging. METHODS: We retrospectively examined 122 patients with squamous cell carcinoma (SCCA) in the lower (88 patients) and upper (34 patients) gingiva. Extension of SCCA into the spaces of the face and neck was evaluated with CT and MR imaging, and findings were surgically confirmed. RESULTS: Spread into the face and neck spaces occurred in 58% of patients. The buccal space was the most common site of spread, occurring in 42% of the lower and of 47% of the upper gingival cancers. Spread into the masticator space occurred from the lower gingival cancers in the molar region (20%) but not from the anterior region. Masticator space involvement from the upper gingiva was rare (4%). The retromolar triangle and buccal space immediately anterior to the ramus served as a corridor for cancer extension from the lower gingiva into the masticator space. The sublingual space (11%) was a less common site of spread from the lower gingiva. CONCLUSION: Gingival cancers spread into the masticator, buccal, and sublingual spaces depending on the primary sites in the oral cavity. An understanding of the face and neck-space anatomy is important in diagnosing cancer extension in the oral cavity gingiva and in treating patients with such disease.