Local gyrification index in patients with major depressive disorder and its association with tryptophan hydroxylase-2 (TPH2) polymorphism.

The tryptophan hydroxylase-2 (TPH2) gene is considered a promising genetic candidate regarding its association with a predisposition to major depressive disorder (MDD). Local gyrification reflects the early neural development of cortical connectivity, and is regarded as a potential neural endophenotype in psychiatric disorders. They aimed to investigate the alterations in the cortical gyrification of the prefrontal cortex and anterior cingulate cortex and their association with the TPH2 rs4570625 polymorphism in patients with MDD. One hundred and thirteen patients with MDD and eighty-six healthy controls underwent T1-weighted structural magnetic resonance imaging and genotyping for TPH2 rs4570625. The local gyrification index of 22 cortical regions in the prefrontal cortex and anterior cingulate cortex was analyzed using the FreeSurfer. The patients with MDD showed significant hypergyria in the right rostral anterior cingulate cortex (P = 0.001), medial orbitofrontal cortex (P = 0.003), and frontal pole (P = 0.001). There was a significant genotype-by-diagnosis interaction for the local gyrification index in the right rostral anterior cingulate cortex (P = 0.003). Their study revealed significant hypergyria of the anterior cingulate cortex and prefrontal cortex and an interactive effect between the diagnosis of MDD and the genotype in the anterior cingulate cortex. This might be associated with the dysfunction of neural circuits mediating emotion processing, which could contribute to pathophysiology of MDD. Hum Brain Mapp 38:1299-1310, 2017. © 2016 Wiley Periodicals, Inc.

Lymph node metastases from gastric cancer: gadofluorine M and gadopentetate dimeglumine MR imaging in a rabbit model.

PURPOSE: To compare the diagnostic performance of gadofluorine M with that of gadopentetate dimeglumine in the diagnosis of lymph node metastases with magnetic resonance (MR) imaging in a rabbit model of gastric cancer. MATERIALS AND METHODS: The study protocol was approved by the institutional animal care committee. VX2 carcinomas were inoculated into the wall of the stomach in 20 rabbits. Gadopentetate dimeglumine-enhanced MR imaging was performed 4-6 weeks after inoculation, and gadofluorine M-enhanced MR imaging was performed approximately 24 hours later. Both MR imaging sets were analyzed separately and independently by four radiologists with respect to confidence level regarding the presence of metastases in lymph nodes and lymph node conspicuity. Statistical analysis was performed by using multiple-reader multiple-case (MRMC) receiver operating characteristic curve analysis and the Wilcoxon signed rank test. RESULTS: Metastases were confirmed at pathologic analysis in 32 of 104 lymph nodes from 16 rabbits. The area under the receiver operating characteristic curve (AUC) for confidence regarding the presence of metastases in lymph nodes was significantly greater for gadofluorine M than for gadopentetate dimeglumine (AUC, 0.947 vs 0.894; P = .009). However, most (81%, 25 of 32) metastatic nodes were necrotic, and no significant difference was obtained in nonnecrotic nodes. For lymph node conspicuity, the gadofluorine M MR imaging set was assigned a significantly higher score than was the gadopentetate dimeglumine MR imaging set by all readers (P < .001). CONCLUSION: Gadofluorine M showed significantly higher accuracy and better conspicuity than gadopentetate dimeglumine in the diagnosis of metastatic nodes, most of which were necrotic, in this animal model of gastric cancer.

Transarterial chemoembolization of a colic branch of the superior mesenteric artery in patients with unresectable hepatocellular carcinoma.

PURPOSE: To evaluate the technical feasibility, safety, and imaging response of transarterial chemoembolization performed through a colic branch of the superior mesenteric artery (SMA) in patients with hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Between July 2000 and June 2009, we observed tumor staining supplied by a colic branch of the SMA in 61 of 5,095 patients (1.2%) with HCC. Computed tomography (CT) scans and digital subtraction angiograms of these patients were retrospectively reviewed by two investigators in consensus to evaluate the tumor location, the technical success of chemoembolization, complications, and imaging response on a follow-up CT scan according to European Association for the Study of the Liver criteria. RESULTS: Tumors supplied by a colic branch of the SMA were located in segment VI (n = 58) or were extrahepatic metastases caused by peritoneal seeding (n = 3). Vessels supplying the tumor arose from the right colic artery (n = 23), middle colic artery (n = 22), or ileocolic artery (n = 26). Selective chemoembolization via a colic branch of the SMA was performed in 24 patients (39%). No patient developed symptoms related to colon ischemia. Complete response or partial response of the tumor fed by a colic branch of the SMA as depicted on follow-up CT was achieved in eight patients (33%). CONCLUSIONS: Chemoembolization via a colic branch of the SMA can be safely performed if the microcatheter can be advanced beyond the antimesenteric border of the colon.

The effects of clinically used MRI contrast agents on the biological properties of human mesenchymal stem cells.

This study was undertaken to compare the labeling efficiencies of three iron-oxide based MRI contrast agents [Feridex, Resovist and monocrystalline iron oxide (MION)] and to evaluate their effects on the biological properties of human mesenchymal stem cells (hMSCs). The hMSCs were cultivated for 1 and 7 days after 24-h labeling with iron oxide nanoparticles (12.5 microg Fe/mL) in the presence of poly-L-lysine (0.75 microg/mL). The hMSCs were labeled more efficiently with use of Feridex, Resovist as compared to MION. No significant differences were observed in terms of viability and proliferation of labeled hMSCs. The level of Oct-4 mRNA increased in labeled hMSCs at day 1 and the cellular phenotype changed from CD45-/CD44+/CD29+ to CD45low/CD44+/CD29+ at day 7, which closely resembles the phenotype of fresh bone marrow-derived hMSCs. Our study has demonstrated that the Feridex or Resovist is the preferred labeling agent for hMSCs. There was a change in Oct-4 and CD45 expression after labeling.

The effects of bone turnover rate on subchondral trabecular bone structure and cartilage damage in the osteoarthritis rat model.

The effects of bone turnover rate on subchondral trabecular changes and cartilage destruction were evaluated in an iodoacetate-induced osteoarthritis rat model. Thirty female rats were randomly divided into three groups as the ovariectomized group, the no-treatment group and the bisphosphonate medication group. Arthritis was induced by a single intra-articular iodoacetate injection into the right tibiofemoral joint. Eight weeks after this injection, tibiofemoral joints on both sides were scanned with a micro-CT. Subchondral trabecular indices were measured on both sides of the tibial lateral condyle epiphysis. In the ovariectomized group, the percentage of bone volume, trabecular thickness and trabecular bone pattern factor of the arthritic sides were lower than those of the control sides, while trabecular separation and structure model index of the arthritic sides were higher than those of the control sides (p < 0.05). In the no-treatment group, only trabecular thickness of the arthritic sides was lower than in the control sides (p < 0.05). In the bisphosphonate medication group, trabecular indices were no different between the arthritic and control sides. Articular cartilage destruction and severity of arthritis increased significantly in the order: ovariectomized group < no-treatment group < bisphosphonate medication group (p < 0.05). After osteoarthritis development, severities of subchondral trabecular changes appeared to be strongly affected by bone turnover rate. Furthermore, a correlation was found between cartilage destruction severity and subchondral trabecular change in the intra-articular iodoacetate-injected osteoarthritis rat model.

Transcatheter arterial chemoembolization for hepatocellular carcinoma: prospective assessment of the right inferior phrenic artery with C-arm CT.

PURPOSE: To assess the usefulness of C-arm computed tomography (CT) of the right inferior phrenic artery (RIPA) in transcatheter arterial chemoembolization of patients with hepatocellular carcinoma (HCC). MATERIALS AND METHODS: From December 2007 to April 2008, C-arm CT of the RIPA was prospectively performed in 32 patients with HCC. Two interventional radiologists who performed C-arm CT assessed the additional information provided with C-arm CT as grade 1 (no additional information), grade 2 (added information without an effect on the treatment plan), or grade 3 (added information with an effect on the treatment plan). Tumor feeders and feeders of a systemic-to-pulmonary shunt were recorded. RESULTS: The information provided by C-arm CT was classified as grade 1 for nine of the 32 patients (28%), grade 2 for 20 patients (63%), and grade 3 for three patients (9%). The most common additional information from C-arm CT scans of the RIPA was the differentiation between the tumor and the systemic-to-pulmonary shunt. A systemic-to-pulmonary shunt from the RIPA was observed in 22 patients (69%), and the most common feeder of a systemic-to-pulmonary shunt was the azygoesophageal branch. CONCLUSIONS: C-arm CT of the RIPA provides additional imaging information for the differentiation of a tumor from a nontumorous condition during chemoembolization for HCC with a suspected blood supply from an RIPA.

Performance of preoperative sonographic staging of papillary thyroid carcinoma based on the sixth edition of the AJCC/UICC TNM classification system.

OBJECTIVE: The purpose of this prospective study was to evaluate the overall performance of sonography for staging papillary thyroid carcinoma. SUBJECTS AND METHODS: Ninety-four consecutive patients with papillary thyroid carcinoma underwent preoperative sonography. Two experienced radiologists prospectively evaluated primary tumors (e.g., diameter, number, presence of extrathyroidal invasion) and cervical lymph nodes for metastasis. A 5-point scale grading capsular abutment was used to evaluate the possibility of extrathyroidal invasion. Lymph nodes were divided into central and lateral groups according to N staging requirements. The sonographic criteria for lymph node metastasis were an absent hilum, hyperechoic change, a round shape, calcification, cystic change, or an abnormal color Doppler pattern. Sonographic results were correlated with histopathologic findings. RESULTS: One hundred twenty-seven cancers in the 94 patients were proven after surgery. Sonography accurately identified 75.9% (22/29) of patients with multifocal cancer and 83.3% (15/18) of patients with bilateral cancers. Using a cutoff value of 50% or more of the tumor abutting the thyroid capsule (grade 2), the sensitivity, specificity, and accuracy of sonography in predicting extrathyroidal invasion were 85.3%, 70.0%, and 74.5%, respectively, and the overall accuracy of sonography for T staging was 67.0% (63/94). One hundred forty-seven cervical lymph node levels were dissected. All six sonographic findings were significantly more frequent in metastatic lymph nodes in the lateral group. However, in the central group, only two criteria-calcification and abnormal Doppler pattern-were found to significantly predict the presence of metastasis. The overall accuracy of sonography for N staging was 71.3% (67/94). CONCLUSION: Sonography is a feasible tool to use for the preoperative staging of papillary thyroid carcinoma.

Detection of metastatic cervical lymph nodes in recurrent papillary thyroid carcinoma: computed tomography versus positron emission tomography-computed tomography.

OBJECTIVE: We sought to determine whether positron emission tomography-computed tomography (PET-CT) is more accurate than CT for detecting metastatic cervical lymph nodes in recurrent papillary thyroid carcinoma (PTC) and to determine the relationship between the CT features and PET-CT findings of metastatic nodes. METHODS: Eleven consecutive patients with recurrent PTC underwent contrast-enhanced CT (CECT) and PET-CT before surgery. We retrospectively evaluated CECT and PET-CT images to determine the presence of metastatic nodes by level-by-level analysis. The CT findings of the PET-CT results that were positive and negative for metastatic nodes were compared. RESULTS: Metastatic nodes were found at 28 (78%) of 36 neck levels surgically explored. The sensitivity, specificity, and accuracy of CECT for the detection of metastatic nodes were 75.0%, 87.5%, and 77.8%, respectively, and those of PET-CT were 35.7%, 87.5%, and 48.6%, respectively, by level-by-level analysis. No significant difference in the CT features was found between the PET-CT findings positive and negative for metastatic nodes (P > 0.05). CONCLUSIONS: Computed tomography is more sensitive and accurate than PET-CT for detecting metastatic lymph nodes in recurrent PTC. No significant relationship was found between the CT features and the PET-CT findings of the metastatic nodes.

Semiquantitative measurement of murine bleomycin-induced lung fibrosis in in vivo and postmortem conditions using microcomputed tomography: correlation with pathologic scores--initial results.

OBJECTIVE: To evaluate whether the semiquantification of lung inflammation and fibrosis in murine bleomycin-induced lung fibrosis using micro-computed tomography (micro-CT) in in vivo and postmortem conditions is feasible, and to correlate micro-CT and pathologic scores. MATERIALS AND METHODS: Bleomycin-induced lung fibrosis was created by intratracheally instilling 3 mg/kg of bleomycin into C57BL/6 mice. Mice were allocated randomly to 2-week, 4-week, and 8-week follow-up groups. In each group, in vivo and follow-up postmortem micro-CT were performed using a voxel size of 35 x 35 x 35 microm. Ground-glass opacity (GGO), consolidation, parenchymal lines, honeycombing, and peripheral bronchial dilatation were scored on micro-CT images in a semiquantitative fashion, whereas inflammation and fibrosis were scored histopathologically. The confidence levels of micro-CT findings were also scored. Correlations between micro-CT and pathologic findings were examined using Spearman rank correlation analysis, and differences between CT scores and confidence levels for in vivo and postmortem micro-CT were subjected to Wilcoxon signed rank testing. Agreements between in vivo and postmortem micro-CT scores were tested using weighted kappa statistics. RESULTS: Consolidation in vivo (r = 0.46) and at postmortem (r = 0.39) and GGO in vivo (r = 0.31) by micro-CT showed fair to moderate correlation with pathologic inflammation scores (P < 0.001). By in vivo and postmortem micro-CT, parenchymal lines (r = 0.72 vs. 0.83) showed good to excellent and peripheral bronchial dilatation (r = 0.47 vs. 0.68) showed moderate to good correlation with pathologic fibrosis scores (P < 0.001). For GGO, consolidation, peripheral bronchial dilatation, and parenchymal lines, fair to moderate agreement was obtained between in vivo and postmortem micro-CT. However, confidence levels for peripheral bronchial dilatation, parenchymal lines, and honeycombing were significantly higher by postmortem micro-CT (P < 0.001). CONCLUSIONS: Micro-CT scores and pathologic scores were found to be well correlated by in vivo and postmortem micro-CT. Although agreements between in vivo and postmortem micro-CT were significant, the confidence levels for fibrosis-related CT findings were significantly higher by postmortem micro-CT.

Hepatocellular carcinoma: detection of blood supply from the right inferior phrenic artery by the use of multi-detector row CT.

PURPOSE: To evaluate retrospectively the ability of multi-detector row computed tomography (CT) to detect blood supply from the right inferior phrenic artery (RIPA) in patients with hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Between July 2006 and June 2007, angiography of the RIPA was performed in 178 patients (151 men, 27 women; mean age, 59 years) with HCC who also had undergone multi-detector row CT. CT scans and digital subtraction angiograms of these patients were retrospectively reviewed by consensus by two investigators to evaluate tumor feeder vessels. RESULTS: Tumor staining fed by the RIPA was noted on angiography in 113 patients (63%). Readers interpreted that the tumor feeder vessels were evident on CT images in 63 of these 113 patients (56%). Young age (odds ratio [OR], 0.934; P < .0001), exophytic growth pattern (OR, 2.702; P = .009), and presence of a visible feeder vessel on CT (OR, 6.933; P < .0001) were significant factors for predicting parasitic blood supply from the RIPA. In a subgroup of tumors smaller than 5 cm, multivariate analysis revealed that young age (OR, 0.94; P = .03) and repeated chemoembolization sessions (OR, 8.65; P = .01) were significant factors. CONCLUSIONS: Visualization of a tumor feeding vessel from the RIPA on multi-detector row CT could be a clue of a parasitic supply of a large tumor. In patients who have received repeated chemoembolization, small tumors in the dorsal hepatic area can be supplied by the RIPA.

Hepatocellular carcinoma: prediction of blood supply from an internal mammary artery with multi-detector row CT.

PURPOSE: To retrospectively evaluate the ability of multi-detector row computed tomography (CT) to predict a blood supply from an internal mammary artery in hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Between January 2003 and March 2007, 9,528 transcatheter arterial chemoembolization sessions were performed in 2,815 patients with HCC at the authors' institution. Sixty-three patients (45 men, 18 women; mean age, 61 years) also underwent internal mammary angiography. CT scans and digital subtraction angiograms were retrospectively reviewed by consensus between two authors to evaluate tumor feeding vessels. Univariate analysis and multiple logistic regression analysis were used to identify factors that help predict the presence of a blood supply from an internal mammary artery to HCCs. RESULTS: Tumor staining, supplied by the internal mammary artery, was noted at angiography in 38 of the 63 patients (60%). Readers found that a tumor feeding vessel was present at CT in 30 of these 38 patients (79%) and found no evidence of a tumor feeding vessel at CT in 22 of the 25 patients without a tumor feeding vessel at angiography (88%). A visible feeding vessel at CT (P = .002) and a large tumor size (>5 cm) were found to be significantly related to a blood supply from an internal mammary artery (P = .025). CONCLUSIONS: Multi-detector row CT enables interventional radiologists to predict blood supply from an internal mammary artery by demonstrating most of its tumor feeding vessels.

Preoperative diagnosis of cervical metastatic lymph nodes in papillary thyroid carcinoma: comparison of ultrasound, computed tomography, and combined ultrasound with computed tomography.

BACKGROUND: Although ultrasound (US) is routinely used for the preoperative evaluation of neck nodes in patients with papillary thyroid carcinoma (PTC), the diagnostic role of computed tomography (CT) has not been established. The purpose of our study is to determine the diagnostic accuracies of US, CT, and combined US and CT (US/CT) for detecting metastatic neck nodes in patients with PTC. METHODS: 165 consecutive patients (140 females and 25 males, mean age 47.9 years) with surgically proven PTC underwent US and CT for preoperative evaluation. CT was performed 2 or 3 months before radioiodine therapy. We assessed the diagnostic accuracies of US, CT, and US/CT using level-by-level analysis. RESULTS: In terms of predicting node metastases, overall sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of US were 51%, 92%, 77%, 81%, and 76%, respectively. Those of CT were 62%, 93%, 81%, 84%, and 80%, respectively, and those of US/CT were 66%, 88%, 79%, 77%, and 81%, respectively, at all neck levels. US/CT significantly increased sensitivity and demonstrated similar specificity compared with US alone in lateral neck levels (p = 0.02 and p = 1.0, respectively). US/CT increased sensitivity (p = 0.01), but decreased specificity compared with US alone in the central neck levels (p = 0.02). CT provided additional benefit for detecting metastatic nodes at more than one level in 8% of all patients, in 14% of patients with suspected nodal metastasis on US, and in 25% of patients with metastatic lymph nodes. CONCLUSIONS: The US/CT combination was found to be superior to US alone for the detection of metastatic lymph nodes in the lateral neck levels in PTC patients by level-by-level analysis.

Diffusion-weighted MR: therapeutic evaluation after chemoembolization of VX-2 carcinoma implanted in rabbit liver.

RATIONALE AND OBJECTIVES: The study goal was to evaluate the ability of diffusion-weighted imaging (DWI) in assessing the viability of rabbit liver VX-2 tumor after transcatheter arterial chemoembolization (TACE). MATERIALS AND METHODS: VX-2 tumors were grown in the livers of 19 rabbits, and chemoembolization was performed. MR imaging was acquired 1 week after TACE. The rabbits were killed for histologic investigation immediately after MR imaging, and the proportion of viable tumor was calculated based on histopathologic examination. Apparent diffusion coefficient (ADC) values were measured in viable and necrotic tumor portion, and were compared using the paired Student's t test. RESULTS: Viable tumors were absent (n = 3), less than 5% (n = 6), and 5% or more (n = 10) at pathology examination. On DWI, three tumors with no viable portion were interpreted as having no viable portion, but three of six tumors with a viable portion of less than 5% were considered as having no viable portion. The mean ADC values of necrotic and viable tumor were 1.653 +/- 0.126 mm(2)/sec and 0.883 +/- 0.407 mm(2)/sec (b = 1000 sec/mm(2)), respectively, and the ADC values of necrotic tumors were significantly greater than those in viable tumors (p < .01). CONCLUSION: Although DWI is a useful tool for assessing tumor viability, viable tumor may not be detected on DWI when it is too small.

Local toxicity of hepatic arterial infusion of hexokinase II inhibitor, 3-bromopyruvate: In vivo investigation in normal rabbit model.

RATIONALE AND OBJECTIVES: 3-Bromopyruvate (3-BrPA), an hexokinase II inhibitor, is known to have high necrotic rate in hyperglycolytic liver tumor models without apparent damage to the normal liver parenchyma. The toxicity of intra-arterial delivery of 3-BrPA in various concentrations has not been specifically investigated using a normal rabbit model. MATERIALS AND METHODS: Twenty rabbits treated with intra-arterial 3-BrPA were divided into four groups according to its dose and infusion level: 1 mM at the left hepatic artery (group I), 5 mM at the left hepatic artery (group II), 25 mM at the left hepatic artery (group III), and 25 mM at the common hepatic artery (group IV). After selective catheterization, 30 ml of 3-BrPA was infused for 2 minutes. As a control group, five rabbits were treated with normal saline. During 1-week follow-up, toxicities were evaluated with blood laboratory results, mortality, and histopathologic examination. RESULTS: All 10 rabbits treated with 25 mM 3-BrPA and 2 rabbits treated with 5 mM 3-BrPA died within 3 days after treatment. In 10 of the 12 deaths, hemorrhagic pyloric or duodenal necrosis was noted. Hepatotoxicities on blood laboratory results were dose dependent but transient in the surviving rabbits. CONCLUSION: Selective intra-arterial administration of 25 mM 3-BrPA can cause considerable toxicities not only in the liver but also in the gastrointestinal system and are dose dependent and can cause death in high doses.

Serial CT findings of Paragonimus infested dogs and the Micro-CT findings of the worm cysts.

OBJECTIVE: To investigate the serial CT findings of Paragonimus westermani infected dogs and the microscopic structures of the worm cysts using Micro-CT. MATERIALS AND METHODS: This study was approved by the committee on animal research at our institution. Fifteen dogs infected with P. westermani underwent serial contrast-enhanced CT scans at pre-infection, after 10 days of infection, and monthly thereafter until six months for determining the radiologic-pathologic correlation. Three dogs (one dog each time) were sacrificed at 1, 3 and 6 months, respectively. After fixation of the lungs, both multi-detector CT and Micro-CT were performed for examining the worm cysts. RESULTS: The initial findings were pleural effusion and/or subpleural ground-glass opacities or linear opacities at day 10. At day 30, subpleural and peribronchial nodules appeared with hydropneumothorax and abdominal or chest wall air bubbles. Cavitary change and bronchial dilatation began to be seen on CT scan at day 30 and this was mostly seen together with mediastinal lymphadenopathy at day 60. Thereafter, subpleural ground-glass opacities and nodules with or without cavitary changes were persistently observed until day 180. After cavitary change of the nodules, the migratory features of the subpleural or peribronchial nodules were seen on all the serial CT scans. Micro-CT showed that the cyst wall contained dilated interconnected tubular structures, which had communications with the cavity and the adjacent distal bronchus. CONCLUSION: The CT findings of paragonimiasis depend on the migratory stage of the worms. The worm cyst can have numerous interconnected tubular channels within its own wall and these channels have connections with the cavity and the adjacent distal bronchus.

FDG-PET for evaluating the antitumor effect of intraarterial 3-bromopyruvate administration in a rabbit VX2 liver tumor model.

OBJECTIVE: We wanted to investigate the feasibility of using FDG-PET for evaluating the antitumor effect of intraarterial administration of a hexokinase II inhibitor, 3-bromopyruvate (3-BrPA), in a rabbit VX2 liver tumor model. MATERIALS AND METHODS: VX2 carcinoma was grown in the livers of ten rabbits. Two weeks later, liver CT was performed to confirm appropriate tumor growth for the experiment. After tumor volume-matched grouping of the rabbits, transcatheter intraarterial administration of 3-BrPA was performed (1 mM and 5 mM in five animals each, respectively). FDG-PET scan was performed the day before, immediately after and a week after 3-BrPA administration. FDG uptake was semiquantified by measuring the standardized uptake value (SUV). A week after treatment, the experimental animals were sacrificed and the necrosis rates of the tumors were calculated based on the histopathology. RESULTS: The SUV of the VX2 tumors before treatment (3.87+/-1.51 [mean+/-SD]) was significantly higher than that of nontumorous liver parenchyma (1.72+/-0.34) (p < 0.0001, Mann-Whitney U test). The SUV was significantly decreased immediately after 3-BrPA administration (2.05+/-1.21) (p = 0.002, Wilcoxon signed rank test). On the one-week follow up PET scan, the FDG uptake remained significantly lower (SUV 1.41+/-0.73) than that before treatment (p = 0.002), although three out of ten animals showed a slightly increasing tendency for the FDG uptake. The tumor necrosis rate ranged from 50.00% to 99.90% (85.48%+/-15.87). There was no significant correlation between the SUV or the SUV decrease rate and the tumor necrosis rate in that range. CONCLUSION: Even though FDG-PET cannot exactly reflect the tumor necrosis rate, FDG-PET is a useful modality for the early assessment of the antitumor effect of intraarterial administration of 3-BrPA in VX2 liver tumor.

Predicting Extrathyroidal Extension in Patients With Papillary Thyroid Microcarcinoma According to a BRAF Mutation.

OBJECTIVES: The aim of this study was to evaluate the association between preoperative parameters and extrathyroidal extension (ETE) of papillary thyroid microcarcinoma (PTMC) according to the BRAF mutation and to evaluate the preoperative predictability of ETE. METHODS: We analyzed the medical records of 332 patients with PTMC (140 in the BRAF- group and 192 in the BRAF+ group). The presence of ETE was subjected to a correlation analysis with age, sex, tumor size, clinical nodal status, and ultrasonography (US) findings. Among the US findings, the correlation between tumors and the thyroid capsule was categorized into four groups; US group A, intraparechymal; US group B, tumor abutting the capsule <50% of diameter; US group C, tumor abutting >50% of diameter; and US group D, tumor destroyed the capsule. The predictive value of ETE, including sensitivity, specificity, and positive and negative predictive values were evaluated. RESULTS: Tumor size and US group were significantly correlated with gross ETE in the BRAF- and BRAF+ groups. Tumor size of 0.5 cm and US groups B and C in the BRAF- group were cutoff values for gross ETE, with a negative predictive value of 100%, whereas tumor size of 0.7 cm and US groups A and B in the BRAF+ group had negative predictive values of 92.4% and 100%, respectively. CONCLUSION: Excluding of ETE by US was categorized according to tumor size and US findings. A different categorization to exclude ETE is needed according to the BRAF mutation.

Diagnostic potential of three-dimensional ultrasound-based virtual cystoscopy: an experimental study using pig bladders.

OBJECTIVE: We sought to investigate the feasibility of 3-dimensional ultrasound (3D US)-based virtual cystoscopy in experimentally designed bladder phantoms using pig bladders. MATERIALS AND METHODS: Ten bladder phantoms with simulated polypoid tumors of different sizes were constructed to provide 3D US-based virtual cystoscopic images. The simulated polypoid tumors were divided by their location into 2 groups: group 1 included the polyps on the anterior and posterior walls, and group 2 included those on the remaining 4 walls. Two genitourinary radiologists independently interpreted the virtual cystoscopic images, with a consensus reached for cases with discrepant results. RESULTS: In a consensus reading, 3D US-based virtual cystoscopy detected 44 (91.7%) of 48 polypoid lesions. All lesions (n = 4) with false-negative results were 5 mm or smaller in diameter, and so the detection rate was 81.8% (18/22) for lesions 5 mm or smaller whereas it was 100% (26/26) for lesions larger than 5 mm. The detection rate for group 1 (93.8%) was not significantly different from that for group 2 (90.6%; P = 1.000). There were 7 false-positive lesions. Of these, 5 lesions were seen in group 1, and reverberation artifacts were the most common source of these errors (n = 4). Blind areas were present in 19 (31.7%) of 60 virtual cystoscopic images and were seen only in group 2. The differences in the false-positive rate and the incidence of blind area were statistically significant between both groups (P = 0.036, P = 0.00008, respectively). CONCLUSION: 3D US-based virtual cystoscopy may have diagnostic potential in the detection of polypoid bladder tumors.

CT analysis of the anterior mediastinum in idiopathic pulmonary fibrosis and nonspecific interstitial pneumonia.

OBJECTIVE: We wanted to determine whether the amount and shape of the anterior mediastinal fat in the patients suffering with usual interstitial pneumonia (UIP) or nonspecific interstitial pneumonia (NSIP) was different from those of the normal control group. MATERIALS AND METHODS: We selected patients who suffered with UIP (n = 26) and NSIP (n = 26) who had undergone CT scans. Twenty-six controls were selected from individuals with normal CT findings and normal pulmonary function tests. All three groups (n = 78) were individually matched for age and gender. The amounts of anterior mediastinal fat, and the retrosternal anteroposterior (AP) and transverse dimensions of the anterior mediastinal fat were compared by one-way analysis of variance and Bonferroni's test. The shapes of the anterior mediastinum were compared using the Chi-square test. Exact logistic regression analysis and polychotomous logistic regression analysis were employed to assess whether the patients with NSIP or UIP had a tendency to show a convex shape of their anterior mediastinal fat. RESULTS: The amount of anterior mediastinal fat was not different among the three groups (p = 0.175). For the UIP patients, the retrosternal AP dimension of the anterior mediastinal fat was shorter (p = 0.037) and the transverse dimension of the anterior mediastinal fat was longer (p = 0.001) than those of the normal control group. For the NSIP patients, only the transverse dimension was significantly longer than those of the normal control group (p < 0.001). The convex shape of the anterior mediastinum was predictive of NSIP (OR = 19.7, CI 3.32-infinity, p < 0.001) and UIP (OR = 24.42, CI 4.06-infinity, p < 0.001). CONCLUSION: For UIP patients, the retrosternal AP and transverse dimensions are different from those of normal individuals, whereas the amounts of anterior mediastinal fat are similar. UIP and NSIP patients have a tendency to have a convex shape of their anterior mediastinal fat.

Feasibility Study of a Contrast-Enhanced Multi-Detector CT (64 Channels) Protocol for Papillary Thyroid Carcinoma: The Influence of Different Scan Delays on Tumor Conspicuity.

BACKGROUND: Recently, a number of studies have advocated the diagnostic benefit of contrast-enhanced computed tomography (CECT) in the current ultrasound (US)-based preoperative evaluation of thyroid cancer. However, no study has been conducted to optimize a CECT protocol focusing on tumor conspicuity using a multi-detector CT scanner. This study aimed at determining the optimal scan delay for increased CT attenuation differences between thyroid cancer and parenchymal background using a biphasic CECT examination. METHODS: This study retrospectively enrolled 84 patients (M:F = 7:77; Mage = 44.8 ± 10.9 years) with 87 papillary thyroid carcinomas (Msize = 14.1 mm) who consecutively underwent US and CECT examination prior to surgery. In each patient, CT scanning was taken twice-once with a 40-second delay and once with a 70-second delay-using a 64-channel multi-detector scanner. After obtaining the mean attenuation value (MAV) of the thyroid cancer and the ipsilateral parenchyma by drawing regions of interest on the CECT images based on their cytopathologic results and US findings, the parenchyma-cancer differences (PCD) between the early and delayed scans were simply compared using a paired t-test. Then, the mean differences in the MAVs of the thyroid cancer and ipsilateral parenchyma (hereafter abbreviated as Group) between the early and delayed scans (abbreviated as Time) were compared after adjusting for the other factors that significantly affected MAVs, such as concentration of iodinated contrast medium (abbreviated as CCM) and size of thyroid cancer (abbreviated as Size) using a repeated-measures general linear model. RESULTS: Because the ipsilateral parenchyma exhibited significantly higher attenuation on the early scan and further decline on the delayed scan compared with thyroid cancer (p < 0.001), the PCD for thyroid cancer was significantly better with a 40-second scan delay than a 70-second delay (58.8 ± 36.6 Hounsfield units [HU] vs. 40.4 ± 25.6 HU; p < 0.001). Similar results were obtained from the repeated-measures general linear model that considered the effects of CCM, Size, Group, and Time, and the interaction of Group and Time. CONCLUSION: Based on this CECT study that adjusted for the effects of CCM and size on MAV, early scans (e.g., 40-second scan delay) are helpful for improving the tumor conspicuity of thyroid cancer on CECT images.