A case of primary rectal angioleiomyoma: review of radiologic finding with histopathologic correlation.

Angioleiomyomas are benign smooth muscle tumors that originate from the tunica media of veins and arteries. They can occur anywhere in the body, but the preferential location of these tumors is the lower extremities. We describe a rare case of rectal angioleiomyoma and present our findings obtained by using computed tomography, magnetic resonance imaging, and histopathological analysis.

Calcified carcinoma of the gallbladder with calcified nodal metastasis presenting as a porcelain gallbladder: a case report.

Porcelain gallbladder is regarded as a risk factor of gallbladder cancer. A porcelain gallbladder with calcified regional lymph nodes was found using computed tomography (CT) and magnetic resonance imaging (MRI) in a 43-year-old man who presented with nausea, vomiting, and abdominal pain. His cholecystectomy specimen showed diffuse wall thickening and contained small gallstones. Histological examination revealed diffuse infiltrative adenocarcinoma with extensive intratumoral calcification (calcified carcinoma). The majority of the calcified material was located within or replaced the tumor glands, and was not found in the stroma. A lymph node was totally replaced with a calcified metastatic adenocarcinoma. To the best of our knowledge, only one case of calcified lymph node metastasis from a calcified carcinoma of the gallbladder has been previously reported in the literature. We herein add a case of calcified carcinoma of the gallbladder with calcified lymph node metastasis, presenting as a porcelain gallbladder on CT and MRI.

CT, MR, (18)F-FDG PET/CT, and their combined use for the assessment of mandibular invasion by squamous cell carcinomas of the oral cavity.

BACKGROUND: a reliable assessment of mandibular invasion is crucial for treatment planning to obtain both radical tumor resection and good functional results. PURPOSE: to retrospectively compare the diagnostic value of three different imaging methods - computed tomography (CT), magnetic resonance (MR) imaging, (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT - and their combined use for detection of mandibular invasion by squamous cell carcinoma (SCC) of the oral cavity. MATERIAL AND METHODS: forty-six patients (39 men and 7 women; mean age, 59.4 years) suspected of having mandibular invasion by SCC of the oral cavity underwent CT, MR, and PET/CT within 2 weeks before surgery. First, each study was reviewed separately for the presence of mandibular invasion by tumors. Then, the value of combined images was assessed based on a confidence rating score for each modality assigned by observers. These results were verified with histopathologic findings. RESULTS: HIstopathologic examination revealed mandibular invasion in 12 of 46 SCCs. The sensitivity, specificity, and accuracy were 41.7%, 100%, and 84.8% for CT; 58.3%, 97.1%, and 87.0% for MR; and 58.3%, 97.1%, and 87.0% for PET/CT, respectively. The comparison of these modalities showed no statistically significant difference among them (P > 0.05). The combination of CT, MR, and PET/CT improved sensitivity (83.3%), without loss of specificity (100%) and accuracy (95.7%), although the difference failed to reach statistical significance (P > 0.05). CONCLUSION: the combined analysis of CT, MR, and PET/CT can improve sensitivity in the detection of mandibular invasion by SCC of the oral cavity.

Small atypical cervical nodes detected on sonography in patients with squamous cell carcinoma of the head and neck: probability of metastasis.

OBJECTIVE: The purpose of this study was to assess the probability of metastasis of small atypical cervical lymph nodes detected on sonography in patients with squamous cell carcinoma (SCC) of the head and neck. METHODS: We reviewed, retrospectively and blindly, sonographic findings of 148 patients (118 men and 30 women; mean age, 58.2 years) who underwent curative neck dissection. Each lymph node was classified by using a 4-point scale: 1, definitely benign; 2, indeterminate (small [short-axis diameter <10 mm for levels I and II and <7 mm for levels III-VI] atypical node); 3, definitely metastatic; and 4, large (>3-cm) metastatic. Lymph nodes were considered atypical if they met at least 1 of the following criteria: a long- to short-axis diameter ratio of less than 2.0, absence of a normal echogenic hilum, and heterogeneous echogenicity of the cortex. These results were verified, on a level-by-level basis, with histopathologic findings. RESULTS: Small atypical nodes were found on sonography in 63 cervical levels of 48 patients, of which 18 (28.6%) were proved to have metastatic nodes. The probability of metastasis was significantly higher with than without a large (>3-cm) ipsilateral metastatic node (0.50 versus 0.20; P = .038) and marginally higher with than without an ipsilateral metastatic node (0.41 versus 0.16; P = .061) but not significantly associated with the T stage of the primary tumor (P = .238) or the presence of an ipsilateral tumor (P = .904). CONCLUSIONS: Metastasis was encountered in about 30% of small atypical cervical nodes on sonography in patients with SCC of the head and neck. Our results indicate that small atypical nodes must be interpreted with consideration of metastatic nodes in the ipsilateral neck.

"Taller-than-wide sign" of thyroid malignancy: comparison between ultrasound and CT.

OBJECTIVE: The objective of our study was to investigate the mechanism of the "taller-than-wide sign"--that is, an anteroposterior dimension-to-transverse dimension ratio of >or= 1 on ultrasound. MATERIALS AND METHODS: Ultrasound and CT images of 90 pathologically proven thyroid masses (57 malignant and 33 benign) smaller than 2 cm in 77 patients (mean age, 45 years) were retrospectively reviewed. Two readers assessed the anteroposterior and transverse dimensions of the mass, anteroposterior-transverse ratio of the mass, anteroposterior dimension of the ipsilateral thyroid lobe, and the position of the common carotid artery (CCA) relative to the thyroid lobe. In addition, the difference in the anteroposterior-transverse ratio of the mass between ultrasound and CT was correlated with the ultrasound characteristics of the thyroid mass (i.e., maximal diameter, location, location within lobe, and composition), histopathologic results, and ultrasound operator. RESULTS: The mean (+/- SD) anteroposterior-transverse ratio of the thyroid masses on ultrasound was significantly lower than that on CT (0.97 +/- 0.34 vs 1.07 +/- 0.28, respectively; p < 0.001), and the differences were significantly greater in benign masses than malignant masses, in masses located at the anterior or mid third of the lobe than those located at the posterior third, and in cystic masses than mixed or solid masses. There were statistically significant differences between the two techniques with regard to the anteroposterior dimension of the ipsilateral thyroid lobe and the position of the CCA, suggesting the effect of probe compression. CONCLUSION: The mechanism of the taller-than-wide sign is no or minimal compressibility of a thyroid mass by the ultrasound probe, which occurs more frequently in malignant masses than in benign masses.

CT features of foreign body granulomas after cosmetic paraffin injection into the cervicofacial area.

PURPOSE: Cosmetic injection of paraffin into cervicofacial tissues has been practiced in the past, especially in Asia, resulting in foreign body granuloma (paraffinoma). The purpose of this study was to describe the computed tomography (CT) findings of cervicofacial paraffinomas. MATERIALS AND METHODS: CT images of 5 patients (4 women and 1 man; age range, 54-80 years; mean age, 67.6 years), who had received direct paraffin injections into cervicofacial tissues, were reviewed retrospectively. RESULTS: The lesions were bilateral and located in the subcutaneous fat layer of the cheek (n = 5), buccal space (n = 2), periorbital area (n = 1), periauricular area (n = 1), neck (n = 1), and nose (n = 1). The predominant CT features were speckled mass formation (n = 3), fat-density nodule (n = 5), high-density nodule (n = 5), nodular calcification (n = 5), and rim calcification (n = 4). CONCLUSION: Paraffinomas in the cervicofacial region have specific CT features that are distinct from other soft tissue masses.

CT, MR, US,18F-FDG PET/CT, and their combined use for the assessment of cervical lymph node metastases in squamous cell carcinoma of the head and neck.

The purpose of this retrospective study was to compare the diagnostic value of four different imaging methods-computed tomography (CT), magnetic resonance (MR) imaging, ultrasonography (US), and (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT-and their combined use for preoperative detection of cervical nodal metastases in head and neck squamous cell carcinoma (SCC). Sixty-seven patients (58 men and 9 women; mean age, 60.1 years) with head and neck SCCs underwent CT, MR, US, and PET/CT before surgery. First, each study was reviewed separately for the presence of nodal metastases. Then, the value of combined images was assessed based on a confidence rating score for each modality assigned by observers. These results were verified, on a level-by-level basis, with histopathologic findings. Histopathologic examination revealed nodal metastases in 74 of 402 nodal levels. The sensitivity, specificity, and accuracy were 77.0%, 99.4%, and 95.3% for CT and MR; 78.4%, 98.5%, and 94.8% for US; and 81.1%, 98.2%, and 95.0% for PET/CT, respectively. The comparison of these modalities showed no statistically significant difference among them (p > 0.05). The combination of CT, MR, US, and PET/CT improved sensitivity (86.5%), without loss of specificity (99.4%) and accuracy (97.0%), although the difference failed to reach statistical significance.

CT, MR, and angiography findings of a solitary fibrous tumor of the larynx: a case report.

This report details the CT, MR, and angiography findings of a solitary fibrous tumor involving the larynx of a 34-year-old man. A precontrast CT scan revealed a well-defined isodense mass in the submucosal region of the supraglottic larynx. The tumor appeared as a mixed intensity lesion on the T1- and T2-weighted MR images. A T2-weighted MR image showed a central, round, and low signal intensity area within the mass. For both the CT and MR images, the mass demonstrated heterogeneous enhancement following the administration of contrast material. The angiography showed a hypervascular tumor with heterogeneous persistent staining.

The prevalence and significance of incidental thyroid nodules identified on computed tomography.

PURPOSE: The purpose of this study was to assess the prevalence of incidental thyroid nodules (ITN) found on computed tomography (CT) of the neck and to determine whether CT characteristics could distinguish malignant from benign thyroid lesions. MATERIALS AND METHODS: We retrospectively reviewed CT scans in 734 patients without known thyroid disease (384 men and 350 women; mean age, 49.8 +/- 13.7 years). The CT findings of ITN such as size, shape (anteroposterior-transverse diameter ratio [AP/T ratio]), margin, peripheral enhancing rim, intralesional calcification, and attenuation characteristics were analyzed and correlated with ultrasonographic (US) findings. RESULTS: One hundred sixty ITNs were noted in 123 (16.8%) patients. Of 120 ITNs whose histological diagnoses were available, 15 (12.5%) were malignant. Malignant nodules more frequently showed nodular or rim calcifications (46.7% vs 13.3%; P < 0.0005), AP/T ratio of greater than 1.0 (33.3% vs 9.5%; P < 0.05), and mean attenuation value on contrast-enhanced scan of greater than 130 Hounsfield units (86.7% vs 49.5%; P < 0.05) than benign nodules. CONCLUSIONS: We found at least a 9.4% (15/160) prevalence of malignancy among ITN detected on CT. The further evaluation with US or biopsy should be performed, if an ITN shows CT features suggesting malignancy (calcification; AP/T ratio, >1.0; or mean attenuation value, >130 HU).

Computer-aided diagnosis for the differentiation of malignant from benign thyroid nodules on ultrasonography.

RATIONALE AND OBJECTIVES: We sought to evaluate the diagnostic performance of an artificial neural network (ANN) and binary logistic regression (BLR) in differentiating malignant from benign thyroid nodules on ultrasonography. MATERIALS AND METHODS: Two experienced radiologists, who were unaware of the histopathological diagnosis, analyzed ultrasonographic (US) features of 109 pathologically proven thyroid lesions (49 malignant and 60 benign) in 96 patients. Each radiologist was asked to evaluate US findings and categorize nodules into one of the two groups (malignant vs. benign) in each case. The following 8 US parameters were assessed for each nodule: size, shape, margin, echogenicity, cystic change, microcalcification, macrocalcification, and halo sign. Statistically significant US findings were obtained with backward stepwise logistic regression and were used for training and testing of the ANN and the BLR. The performance of the ANN and BLR was compared to that of the radiologists using receiver-operating characteristic (ROC) analysis. RESULTS: Statistically significant US findings were size, margin, echogenicity, cystic change, and macrocalcification of the nodules. The area under the ROC curve (Az) values of ANN and BLR were 0.9492 +/- 0.0195 and 0.9046 +/- 0.0289, respectively. The Az value was 0.8300 +/- 0.0359 for reader 1 and 0.7600 +/- 0.0409 for reader 2. The Az values for ANN and BLR were significantly higher than those for both radiologists (all p < .05). CONCLUSION: The performance of the ANN and the BLR was better than that of the radiologists in the distinction of benign and malignant thyroid nodules.

Anaplastic thyroid carcinoma: computed tomographic differentiation from other thyroid masses.

BACKGROUND: Anaplastic thyroid carcinoma is rare but is one of the most aggressive malignancies. Therefore, accurate diagnosis is important in order to provide appropriate therapy. PURPOSE: To establish useful computed tomographic (CT) criteria for differentiating anaplastic carcinoma from other thyroid masses. MATERIAL AND METHODS: The CT scans of nine patients with anaplastic carcinomas were retrospectively reviewed and compared with those of 32 patients with papillary carcinomas (n = 12) or benign lesions (n = 20) exceeding a maximum diameter of 2.0 cm. Image analysis was performed according to the following CT parameters: size, margin (well defined or ill defined), composition (cystic, mixed, or solid), mean attenuation value, ratio of attenuation of the mass to that of the adjacent muscle (M/m attenuation ratio), necrosis (present or absent), and calcification (stippled, nodular, or absent) of the thyroid mass; and tumor-spreading patterns including the presence of surrounding normal thyroid tissue in the involved lobe, involvement of the contralateral thyroid lobe, extension into the adjacent structures, and cervical lymphadenopathy. RESULTS: Anaplastic carcinomas appeared as large (average 4.6 cm), solid (100%), and ill-defined (88.9%) masses accompanied by necrosis (100%), nodular calcification (44.4%), direct invasion into the adjacent organs (55.6%), and cervical lymph node involvement (77.8%). Tumor necrosis was the most valuable parameter in differentiating anaplastic carcinomas from other thyroid masses. Patient age (>70 years) and low attenuation value on postcontrast scan (attenuation value <100 HU, or M/m attenuation ratio <1.3) are also helpful predictors for anaplastic carcinoma. CONCLUSION: If a patient is older than 70 years of age and has a large necrotic thyroid mass of low attenuation, anaplastic carcinoma should be included in the differential diagnosis.

Peripheral calcification in thyroid nodules: ultrasonographic features and prediction of malignancy.

OBJECTIVE: The purpose of this study was to investigate the association between peripheral calcification in thyroid nodules detected on ultrasonography and thyroid malignancy. METHODS: We retrospectively analyzed the ultrasonographic features of 65 pathologically proven thyroid lesions showing peripheral calcification for their correlation with histopathologic results. The following ultrasonographic parameters were assessed for each nodule: size (maximal dimension), shape (anteroposterior dimension/transverse dimension ratio), internal echogenicity (hypoechoic, isoechoic, hyperechoic, or invisible), halo sign (present or absent), type of calcification (stippled, curvilinear/smooth margin, or curvilinear/irregular margin), and extent of calcification (arc or rim). RESULTS: Twelve (18.5%) of 65 thyroid nodules with peripheral calcification were malignant, and 53 (81.5%) were benign. Patient demographics (age and sex) and ultrasonographic features of the nodules (size, shape, internal echogenicity, halo sign, and type and extent of calcification) did not show any significant differences between benign and malignant groups. CONCLUSIONS: The relatively high prevalence of malignancy and no reliable criterion for malignancy in thyroid nodules with peripheral calcification indicate that fine-needle aspiration or careful ultrasonographic follow-up may be warranted in these cases.

Changes in the abdominal fat distribution after gastrectomy: computed tomography assessment.

BACKGROUND: We investigated the postoperative changes in visceral fat, as compared with subcutaneous fat in patients who underwent total gastrectomy (TG) or subtotal gastrectomy (STG). METHODS: Thirty-eight patients of gastric cancer who underwent abdominal and pelvic computed tomography scans before and after STG (n = 28) or TG (n = 10) were examined. The volumes of the total, visceral and subcutaneous adipose tissues (TAT, VAT and SAT, respectively) were calculated in each scan using the multislice method. Changes between the preoperative data and results obtained at 6 and 12 months after surgery were evaluated. RESULTS: In the first 6 months, there were significant decreases in TAT, VAT and SAT values in the TG (-2424 +/- 1309, -1535 +/- 1056 and -889 +/- 613 cm(3), respectively) and STG (-1590 +/- 1309, -1024 +/- 645, and -578 +/- 659 cm(3), respectively) groups. From 6 to 12 months after surgery, a further significant reduction in VAT (-351 +/- 196 cm(3)) in the TG group and significant regains in TAT and SAT (850 +/- 1205 and 757 +/- 1032 cm(3), respectively) in the STG group were observed. The ratio of VAT to SAT calculated in both groups decreased continuously in all periods of observation. CONCLUSION: Patients who underwent gastrectomy lost TAT, VAT and SAT during the postoperative period up to 6 months and the decrease in VAT was greater and more persistent than the decrease in SAT, particularly in the TG group.

Multi-detector row CT of the head and neck: comparison of different volumes of contrast material with and without a saline chaser.

INTRODUCTION: The aim of this study was to determine the effect of different volumes of contrast material with and without a saline chaser on tissue enhancement in multidetector row CT (MDCT) of the head and neck. METHODS: In a blind prospective fashion, 120 patients were randomized into the following four groups: group 1, 80 ml contrast material administered at a flow rate of 2.0 ml/s; group 2, 80 ml followed by 40 ml saline at 2.0 ml/s; group 3, 60 ml at 1.5 ml/s; and group 4, 60 ml followed by 30 ml saline at 1.5 ml/s. The attenuation values of the carotid artery, internal jugular vein, and muscle were measured at an interval of 1.5 s in each patient. The degree of perivenous artifacts was subjectively assessed. RESULTS: Mean attenuation values in the carotid artery and internal jugular vein were significantly higher in groups 1 and 2 than in groups 3 and 4. The width of the diagnostic window (both carotid and jugular enhancement >150 HU) were significantly longer in groups 1 and 2 than in groups 3 and 4. The addition of a saline chaser did not result in improved vascular enhancement or a wider diagnostic window, but reduced perivenous artifacts, compared with using contrast material alone. CONCLUSION: Reduction of contrast material from 80 to 60 ml results in insufficient enhancement of neck vessels. In addition, the benefit of a saline chaser technique is not obvious except for its ability to reduce perivenous artifacts.

Tailgut cyst: MRI evaluation.

OBJECTIVE: The purpose of our study was to evaluate the MRI features of tailgut cysts in five patients. CONCLUSION: Our results suggest that MRI may be useful in the diagnosis of tailgut cyst. A multilocular cystic mass in the presacral space is a characteristic MRI finding of tailgut cyst, which may also be revealed as a cystic mass consisting of a large cyst accompanied by a small peripheral cyst. However, further studies are necessary to establish the usefulness of MRI for evaluating tailgut cysts.