Characteristics of Early Pancreatic Cancer: Comparison between Stage 1A and Stage 1B Pancreatic Cancer in Multicenter Clinical Data Warehouse Study.

BACKGROUND: Little is known about the characteristics of early pancreatic cancer. We aimed to identify the characteristics, clues for early detection, and prognostic factors for early pancreatic cancer by analyzing a large number of patients with stage 1 pancreatic cancer. METHODS: A clinical data warehouse that includes databases of all the medical records of eight academic institutions was used to select and analyze patients with pancreatic cancer that had been diagnosed from January 2010 to May 2023. RESULTS: In total, 257 stage 1 pancreatic cancer patients were included. There were 134 men (52%), and the average age was 67.2 ± 9.9 years. Compared to patients with stage 1B pancreatic cancer (2-4 cm), patients with stage 1A pancreatic cancer (≤2 cm) had more tumors in the body and tail than in the head (p = 0.028), more new-onset diabetes and less old diabetes (p = 0.010), less jaundice (p = 0.020), more follow-up of IPMN (intraductal papillary mucinous neoplasm, p = 0.029), and more histories of acute pancreatitis (p = 0.013). The pathological findings showed that stage 1A pancreatic cancer involved more IPMNs (p < 0.001) and lower pancreatic intraepithelial neoplasia (p = 0.004). IPMN was present in all 13 pancreatic tumors that were smaller than 1 cm. In multivariate analysis, positive resection margin (odds ratio [OR] 1.536, p = 0.040), venous invasion (OR 1.710, p = 0.010), and perineural invasion (OR 1.968, p = 0.002) were found to be risk factors affecting disease-free survival, while old diabetes (odds ratio [OS] 1.981, p = 0.003) and perineural invasion (OR 2.270, p = 0.003) were found to be risk factors affecting overall survival. CONCLUSIONS: IPMN is closely associated with early pancreatic cancer and may provide an opportunity for early detection. The presence of perineural invasion was a crucial prognostic factor for both overall and disease-free survival in patients with stage 1 pancreatic cancer.

mRNA expression of CDH3, IGF2BP3, and BIRC5 in biliary brush cytology specimens is a useful adjunctive tool of cytology for the diagnosis of malignant biliary stricture.

Although advances have been made in diagnostic tools, the distinction between malignant and benign biliary strictures still remains challenging. Intraductal brush cytology is a convenient and safe method that is used for the diagnosis of biliary stricture, but, low sensitivity limits its usefulness. This study aimed to demonstrate the usefulness of mRNA expression levels of target genes in brush cytology specimens combined with cytology for the diagnosis of malignant biliary stricture. Immunohistochemistry for cadherin 3 (CDH3), p53, insulin-like growth factor II mRNA-binding protein 3 (IGF2BP3), homeobox B7 (HOXB7), and baculoviral inhibitor of apoptosis repeat containing 5 (BIRC5) was performed in 4 benign and 4 malignant bile duct tissues. Through endoscopic or interventional radiologic procedures, brush cytology specimens were prospectively obtained in 21 and 35 paitents with biliary strictures. In the brush cytology specimens, the mRNA expressions levels of 5 genes were determined by real-time polymerase chain reaction. Immunohistochemistry for CDH3, p53, IGF2BP3, HOXB7, and BIRC5 all showed positive staining in malignant tissues in contrast to benign tissues, which were negative. In the brush cytology specimens, the mRNA expression levels of CDH3, IGF2BP3, HOXB7, and BIRC5 were significantly higher in cases of malignant biliary stricture compared with cases of benign stricture (P = 0.006, P < 0.001, P < 0.001, and P = 0.001). The receiver-operating characteristic curves of these 4 mRNAs demonstrated that mRNA expression levels are useful for the prediction of malignant biliary stricture (P = 0.006, P < 0.001, P < 0.001, and P = 0.002). The sensitivity and specificity, respectively, for malignant biliary stricture were 57.1% and 100% for cytology, 57.1% and 64.3% for CDH3, 76.2% and 100% for IGF2BP3, 71.4% and 57.1% for HOXB7, and 76.2% and 64.3% for BIRC5. When cytology was combined with the mRNA levels of CDH3, IGF2BP3, or BIRC5, the sensitivity for malignant biliary stricture improved to 90.5%. The measurement of the mRNA expression levels of CDH3, IGF2BP3, and BIRC5 by real-time polymerase chain reaction combined with cytology was useful for the differentiation of malignant and benign biliary strictures in brush cytology specimens.

Radiation Doses of Various CT Protocols: a Multicenter Longitudinal Observation Study.

Emerging concerns regarding the hazard from medical radiation including CT examinations has been suggested. The purpose of this study was to observe the longitudinal changes of CT radiation doses of various CT protocols and to estimate the long-term efforts of supervising radiologists to reduce medical radiation. Radiation dose data from 11 representative CT protocols were collected from 12 hospitals. Attending radiologists had collected CT radiation dose data in two time points, 2007 and 2010. They collected the volume CT dose index (CTDIvol) of each phase, number of phases, dose length product (DLP) of each phase, and types of scanned CT machines. From the collected data, total DLP and effective dose (ED) were calculated. CTDIvol, total DLP, and ED of 2007 and 2010 were compared according to CT protocols, CT machine type, and hospital. During the three years, CTDIvol had significantly decreased, except for dynamic CT of the liver. Total DLP and ED were significantly decreased in all 11 protocols. The decrement was more evident in newer CT scanners. However, there was substantial variability of changes of ED during the three years according to hospitals. Although there was variability according to protocols, machines, and hospital, CT radiation doses were decreased during the 3 years. This study showed the effects of decreased CT radiation dose by efforts of radiologists and medical society.

Interleukin-6 is associated with obesity, central fat distribution, and disease severity in patients with acute pancreatitis.

BACKGROUND/OBJECTIVE: Acute pancreatitis (AP) is a systemic inflammatory disease, and cytokines are suggested to be related to the course of AP. Obesity and central fat distribution are considered to have been associated with severe AP. This study investigated the profile of inflammatory cytokines in AP to determine how they are related to obesity, central fat distribution, and AP severity. METHODS: Fifty-nine patients with AP were prospectively enrolled in the study. Body mass index and waist circumference were obtained at admission. Serum levels of inflammatory cytokines, IL-Iß, IL-1ra, IL-6, TNF-α, sTNFR-I, and sTNFR-II, were measured on day 1 and 2 of AP. RESULTS: Of the patients included in the study, 19 (32%) were overweight, 23 (39%) had central fat distribution, and 23 (39%) had moderate AP. IL-1ra and IL-6 were significantly higher in overweight patients compared with non-overweight patients. IL-1ra, IL-6, TNF-α, and sTNFR-I were significantly higher in patients with central fat distribution compared with patients with non-central fat distribution. IL-6, sTNFR-I, and sTNFR-II were significantly higher in patients with moderate pancreatitis compared to those with mild pancreatitis. Among the six cytokines, IL-6 was commonly elevated in patients with central fat distribution, overweight, and moderate AP. The areas under the receiver operating characteristic curves of IL-6 for predicting the association with overweight, central fat distribution, and AP severity were 0.678, 0.716, and 0.801, respectively (P < 0.05). CONCLUSIONS: IL-6 is a good marker for AP severity and is associated with obesity and central fat distribution in AP patients.

Diagnostic accuracy of 64-slice multidetector CT angiography for detection of in-stent restenosis of vertebral artery ostium stents: comparison with conventional angiography.

BACKGROUND: There are very few reports assessing in-stent restenosis (ISR) after vertebral artery ostium (VAO) stents using multidetector computed tomography (MDCT). PURPOSE: To compare the diagnostic accuracy of computed tomography angiography (CTA) using 64-slice MDCT with digital subtraction angiography (DSA) for detection of significant ISR after VAO stenting. MATERIAL AND METHODS: The study evaluated 57 VAO stents in 57 patients (39 men, 18 women; mean age 64 years [range, 48-90 years]). All stents were scanned with a 64-slice MDCT scanner. Three sets of images were reconstructed with three different convolution kernels. Two observers who were blinded to the results of DSA assessed the diagnostic accuracy of CTA for detecting significant ISR (≥50% diameter narrowing) of VAO stents in comparison with DSA as the reference standard. The sensitivity, specificity, positive and negative predictive values, and accuracy were calculated. RESULTS: Of the 57 stents, 46 (81%) were assessable using CTA, while 11 (19%) were not. No stents with diameters ≤2.75 mm were assessable. DSA revealed 13 cases of significant ISR in all stents. The respective sensitivity, specificity, positive and negative predictive values, and accuracy were 92%, 82%, 60%, 97%, and 84% for all stents. On excluding the 11 non-assessable stents, the respective values were 88%, 95%, 78%, 97%, and 93%. Of the 46 CTA assessable stents, eight significant ISRs were diagnosed on DSA. Seven of eight patients with significant ISR by DSA were diagnosed correctly with CTA. The area under the receiver-operating characteristic curve (AUC) was 0.87 for all stents and 0.91 for assessable stents, indicating good to excellent agreement between CTA and DSA for detecting significant ISR after VAO stenting. CONCLUSION: Sixty-four-slice MDCT is a promising non-invasive method of assessing stent patency and can exclude significant ISR with high diagnostic values after VAO stenting.

Initial large diameter of common bile duct is associated with long-term dilatation of bile duct after endoscopic extraction of stones.

OBJECTIVE: To investigate the time and extent of recovery of dilated common bile duct (CBD) after the extraction of CBD stones and to identify the factors related to the long-term dilatation of the CBD after stone removal. METHODS: Data of 329 consecutive patients undergoing endoscopic extraction of CBD stones from January 2008 to December 2012 were retrospectively reviewed. Finally, 44 patients were enrolled in the study. RESULTS: The CBD diameter significantly decreased after stone extraction (P < 0.001). However, the CBD diameter in patients who were followed up for 1 week and longer and <1 week did not differ significantly. The diameter decreased more in patients with an initial CBD diameter ≥ 15 mm than in those with an initial CBD diameter <15 mm before stone extraction (P = 0.007), but the normalization of dilated CBD was less frequent in patients with a large initial CBD diameter. The factors related to the long-term dilatation of CBD (>10 mm for >6 months) were initial CBD diameter, the largest diameter of CBD stone and endoscopic papillary large balloon dilatation. Initial CBD diameter was an independent factor with multivariate analysis (OR 1.754, P = 0.017). CONCLUSIONS: The CBD diameter recovers rapidly after the extraction of CBD stones. An initial large CBD diameter before stone extraction is associated with the long-term dilatation of CBD.

In vivo evaluation of carotid artery stents using multi-detector-row computed tomography angiography: comparison of 3 kernels.

OBJECTIVE: The objective of this study was to assess the lumen visibility of carotid artery stents using multi-detector-row computed tomography (MDCT) angiography; compare medium-smooth, medium-sharp, and sharp kernels; and correlate these results to those of digital subtraction angiography (DSA). METHODS: We retrospectively evaluated 52 stents from 51 patients who underwent 16- and 64-slice MDCT angiography. Lumen diameters were measured 3 times by 2 neuroradiologists, and artificial luminal narrowing was calculated. To assess detection of in-stent restenosis (>50%), 2 neuroradiologists evaluated all MDCT and DSA images. RESULTS: Excellent intraobserver and interobserver agreements were obtained for the lumen diameter measurements (P < 0.001). Lumen diameter visibility improved, and artificial luminal narrowing decreased from the medium-smooth kernel to the sharp kernel. Visual estimation of all CT angiography using the 3 kernels showed high accuracy for detection of in-stent restenosis (>50%), compared with DSA. CONCLUSIONS: Computed tomography angiography using a sharp kernel allows for more accurate assessment of lumen visibility after carotid artery stenting.

Giant cell tumor with secondary aneurysmal bone cyst: a unique presentation with an ossified extraosseous soft tissue mass.

The authors describe a case of giant cell tumor (GCT) with secondary aneurysmal bone cyst (ABC) in a 44-year-old man with chronic, intermittent knee pain. A unique feature is the presentation of GCT with an ossified extraosseous soft tissue mass. Radiograph demonstrates a multiloculated lytic lesion in the distal meta-epiphyseal region of the femur with an adjacent extraosseous soft tissue mass. The soft tissue mass was partially ossified along its margin and internal septa. MRI demonstrates a multiloculated lesion in the distal femur with multiple fluid-fluid levels and cortical penetration of the lesion. Both the intraosseous lesion and extraosseous soft tissue mass have similar MR signal characteristics. At surgery, the intraosseous component was found to be contiguous with the extraosseous soft tissue mass through a cortical perforation. To the best of our knowledge, this is the first case report of GCT with aneurysmal bone cyst initially presenting with an extraosseous soft tissue mass.

Common bile duct stones on multidetector computed tomography: attenuation patterns and detectability.

AIM: To investigate the attenuation patterns and detectability of common bile duct (CBD) stones by multidetector computed tomography (MDCT). METHODS: Between March 2010 and February 2012, 191 patients with suspicion of CBD stones undergoing both MDCT and endoscopic retrograde cholangiopancreatography (ERCP) were enrolled and reviewed retrospectively. The attenuation patterns of CBD stones on MDCT were classified as heavily calcified, radiopaque, less radiopaque, or undetectable. The association between the attenuation patterns of CBD stones on MDCT and stone type consisting of pure cholesterol, mixed cholesterol, brown pigment, and black pigment and the factors related to the detectability of CBD stones by MDCT were evaluated. RESULTS: MDCT showed CBD stones in 111 of 130 patients in whom the CBD stones were demonstrated by ERCP with 85.4% sensitivity. The attenuation patterns of CBD stones on MDCT were heavily calcified 34 (26%), radiopaque 31 (24%), less radiopaque 46 (35%), and undetectable 19 (15%). The radiopacity of CBD stones differed significantly according to stone type (P < 0.001). From the receiver operating characteristic curve, stone size was useful for the determination of CBD stone by MDCT (area under curve 0.779, P < 0.001) and appropriate cut-off stone size on MDCT was 5 mm. The factors related to detectability of CBD stones on MDCT were age, stone type, and stone size on multivariate analysis (P < 0.05). CONCLUSION: The radiopacity of CBD stones on MDCT differed according to stone type. Stone type and stone size were related to the detectability by MDCT, and appropriate cut-off stone size was 5 mm.

Evaluation of middle cerebral artery stents using multidetector row CT angiography in vivo study: comparison of the three different kernels.

BACKGROUND: There are very few reports assessing middle cerebral artery (MCA) stents using multidetector computed tomography (MDCT). PURPOSE: To assess MCA stents using multidetector CT angiography (CTA) in vivo evaluation: the differences in the CTA results according to the three different kernels. MATERIAL AND METHODS: We retrospectively evaluated 27 MCA stents from 26 patients who underwent CTA with 16- and 64-slice MDCT after percutaneous transluminal angioplasty and stenting (PTAS). By CTA, using medium-smooth kernel (B30), medium-sharp kernel (B50), and sharp kernel (B60), the lumen diameter, artificial luminal narrowing (ALN), and subjective visibility score of the stented vessels were evaluated. The subjective visibility score ranged from 1 (poor quality) to 5 (excellent) using a five-point scale. RESULTS: There were excellent inter-observer agreements for the lumen diameter measurements (P < 0.001). The mean diameter of the stented vessels was 2.10 ± 0.31 mm on digital subtraction angiography (DSA), 0.93 ± 0.20 mm on CTA using B30, 1.18 ± 0.27 mm on CTA using B50, and 1.29 ± 0.29 mm on CTA using B60. The mean ALN was 55.7 ± 6.0% on CTA using B30, 43.8 ± 7.5% on CTA using B50, and 38.7 ± 8.3% on CTA using B60. CTA with higher kernels had a smaller ALN than images with smaller kernels. The median subjective visibility score on the CTA using B50 was 3, which was higher than for the other kernels. The differences in the lumen diameter, ALN, and the subjective visibility score of the stented vessels on CTA using the three different kernels was statistically significant (P < 0.001). CONCLUSION: The sharp kernel was better to assess the lumen diameter and ALN, but was inferior to the medium-sharp kernel for in-stent evaluation due to high image-to-noise. CTA with medium-sharp kernel showed good lumen visibility and acceptable ALN for MCA stents. This could therefore be a non-invasive, readily applicable clinical method for assessing MCA stent patency after stent placement.

Role of magnetic resonance cholangiopancreatography for choledocholithiasis: analysis of patients with negative MRCP.

OBJECTIVE: To investigate the negative predictive value of magnetic resonance cholangiopancreatography (MRCP) for common bile duct (CBD) stones and the prognosis of patients suspected to have choledocholithiasis in whom the MRCP was negative for CBD stones. METHODS: We enrolled the patients suspected to have choledocholithiasis in whom the MRCP was negative for the CBD stones between January 2008 and March 2011 and retrospectively analyzed the outcomes of 115 patients. RESULTS: Endoscopic retrograde cholangiopancreatography (ERCP) was performed in 27 patients (23%, group 1), and none had CBD stones. The negative predictive value of MRCP was 100%. During a median follow-up of 18.3 months, acute cholangitis with newly developed CBD stones occurred in two patients. Eighty-eight patients (77%, group 2) did not undergo ERCP and all recovered from acute cholangitis without CBD surgery. During a median follow-up of 18.7 months, acute cholangitis, acute cholecystitis, gallstone pancreatitis, and pancreatico-biliary cancers occurred in four (4.6%), three (3.5%), one (1.2%), and three (3.5%) patients, respectively. New CBD stones were found in only two patients among four patients with recurrent acute cholangitis. No patient had recurrent cholangitis caused by MRCP-missed CBD stones. The rates of recurrent cholangitis and cholangitis-free survival did not differ between groups 1 and 2. CONCLUSION: The negative predictive value of MRCP was very high. ERCP can be reserved for patients who are MRCP negative for choledocholithiasis, but close follow-up is needed because of recurrent cholangitis or pancreatico-biliary cancer.

Periosteal autograft for articular cartilage defects in dogs: MR imaging and ultrasonography of the repair process.

BACKGROUND: Autologous periosteal grafting is used as treatment for cartilage defects. PURPOSE: To assess the role of MR imaging and ultrasonography in the evaluation of the post-graft repair process with imaging and histologic correlation. MATERIAL AND METHODS: Periosteal grafts obtained from the tibia of eight dogs were transplanted to the experimental cartilage defects in the femoral condyles (15 knees). The control group was comprised of three dogs (five knees). MR imaging using 4.7T and ultrasonography of the grafted specimens was performed at one, two, four, eight, and 16 weeks after transplantation. The animals were sacrificed at the time of imaging at the previously specified intervals. Histologic analysis with imaging correlation was subsequently performed. RESULTS: All specimens taken from one to 16 weeks demonstrated periosteal proliferation in the graft. At one week, experimental cartilage defects were no longer present on MR imaging. Area of high signal intensity (SI) in the defect was present which corresponded to hemorrhage, edema, and fibrosis on histology. At two, four, and eight weeks, all but two graft demonstrated heterogeneous high SI on T2-weighted image, consistent with immature cartilage. At 16 weeks, all grafts showed heterogeneous isointense to adjacent cartilage on all sequences, which corresponded to dominant mature cartilage. The repair tissue near the exposed subchondral bone revealed heterogeneous high SI on T2-weighted images. This corresponded to the fibrosis with vascular penetration and edema. In the control group, no cartilage repair was noted within cartilage defects. The serial MR features of the grafted area correlated well with the histologic findings. Serial sonographic findings were not sufficient to provide the regenerated cartilage maturity. CONCLUSION: MR imaging is capable of depicting the repair characteristics following periosteal grafting for articular cartilage defects. MR imaging may provide useful information in the assessment of the graft appearance with definite implications regarding the degree and success of incorporation.

Relationship of visceral and subcutaneous adiposity with renal function in people with type 2 diabetes mellitus.

BACKGROUND: Obesity and diabetes mellitus (DM) are established risk factors for the development of chronic kidney disease. Visceral adiposity (VAT) and subcutaneous adiposity (SAT) may be associated with the differential metabolic risk. Our study was performed to determine whether VAT or SAT was associated with the decrease of renal function in people with type 2 DM. METHODS: Nine hundred and twenty-nine people with type 2 DM and who had undergone abdominal computed tomography assessment of the SAT and VAT areas were included. The estimated glomerular filtration rate (eGFR) was calculated using the Cockcroft-Gault equation and the Modification of Diet in Renal Disease (MDRD) four-variable equation at the time of the assessment of the SAT and VAT areas. RESULTS: VAT was negatively associated with eGFR using the MDRD equation after adjustment for the clinical variables (ß-coefficient = - 0.075, P = 0.034), while SAT was not significantly associated with eGFR. There was no significant association between the abdominal adiposity measurements and the eGFR using the Cockcroft-Gault formula. When stratifying the individuals by the body mass index groups, VAT was negatively associated with eGFR by the MDRD equation and the Cockcroft-Gault formula in the overweight and obese subjects after adjustment for the clinical variables, while there was no significant association between the VAT and the eGFR in the normal weight subjects. SAT was not significantly associated with eGFR in the normal weight, overweight and obese subjects. CONCLUSIONS: Our data suggest that VAT may be an additional prognostic factor for the decrease of renal function especially in the overweight or obese subjects with type 2 DM.

Emphasis on the MR imaging findings of brown tumor: a report of five cases.

OBJECTIVE: Brown tumors are focal reactive osteolytic lesions that are encountered in patients with primary or secondary hyperparathyroidism, and these tumors have nonspecific magnetic resonance (MR) imaging findings. However, there are only a few reports on MR imaging of brown tumors. The purpose of this study is to describe the spectrum of MR imaging findings of brown tumors. MATERIALS AND METHODS: The MR imaging features of five patients with clinical and pathological evidence of brown tumor were retrospectively reviewed by two radiologists. The patients had primary hyperparathyroidism, which was confirmed as parathyroid adenoma (n = 2) and parathyroid carcinoma (n = 3). The MR images were evaluated for the presence of solid or cystic portions, the signal intensity of the lesions, the contrast enhancement pattern and the presence of cortex destruction and fluid-fluid levels. RESULTS: Twelve bone lesions were detected on the MR images of five patients; three lesions in two patients, four lesions in one patient, and one lesion in two patients. The tumor was solid in three lesions, mixed solid and cystic in four, and cystic in five. All the solid lesions were accompanied by mixed lesions. Discontinuity of the cortex and adjacent soft-tissue enhancement were seen in all the solid lesions. Fluid-fluid levels were seen in two cases within the cystic component of the mixed lesions and cystic lesions. CONCLUSIONS: The five patients with brown tumor demonstrated a wide spectrum of MR imaging findings. There are few lesions that are osteolytic on the radiographs and that show a short T2 on MR imaging, such as brown tumor. Multiple cystic or mixed lesions are the expected findings of brown tumors.

Image quality improvement after implementation of a CT accreditation program.

OBJECTIVE: The purpose of this study was to evaluate any improvement in the quality of abdominal CTs after the utilization of the nationally based accreditation program. MATERIALS AND METHODS: Approval was obtained from the Institutional Review Board, and informed consent was waived. We retrospectively analyzed 1,011 outside abdominal CTs, from 2003 to 2007. We evaluated images using a fill-up sheet form of the national accreditation program, and subjectively by grading for the overall CT image quality. CT scans were divided into two categories according to time periods; before and after the implementation of the accreditation program. We compared CT scans between two periods according to parameters pertaining to the evaluation of images. We determined whether there was a correlation between the results of a subjective assessment of the image quality and the evaluation scores of the clinical image. RESULTS: The following parameters were significantly different after the implementation of the accreditation program: identifying data, display parameters, scan length, spatial and contrast resolution, window width and level, optimal contrast enhancement, slice thickness, and total score. The remaining parameters were not significantly different between scans obtained from the two different periods: scan parameters, film quality, and artifacts. CONCLUSION: After performing the CT accreditation program, the quality of the outside abdominal CTs show marked improvement, especially for the parameters related to the scanning protocol.

Assessment of vertebral artery stents using 16-slice multi-detector row CT angiography in vivo evaluation: comparison of a medium-smooth kernel and a sharp kernel.

OBJECTIVES: To assess the lumen visibility of extracranial vertebral artery stents examined with 16-slice multi-detector row computed tomography (MDCT) angiography in vivo using a medium-smooth kernel (B30s) and a sharp kernel (B60s), and to compare these with digital subtraction angiography (DSA) after stent placement. METHODS: Twenty stents from 20 patients (14 men, 6 women; mean age, 62.7+/-10.1 years) who underwent CT angiography (CTA) with 16-slice MDCT were retrospectively analyzed. In CT angiograms using a B30s and a B60s, the lumen diameters and CT attenuations of the stented vessels were measured three times by three observers, and artificial luminal narrowing (ALN) was calculated. To assess measurement reliability on CT angiograms, the intraclass correlation coefficient (ICC) was used. DSA served as the reference standard for the in-stent luminal measurements on CT angiography. The median interval between CT angiography and DSA was 1 day (range 1-10). RESULTS: For interobserver reliability, intraclass correlation coefficients for the lumen diameters on CT angiograms with a B30s and a B60s were 0.90 and 0.96, respectively. The lumen diameters on CT angiograms using a B30s were consistently smaller than that on CT angiograms using a B60s (p<0.01). The mean ALN was 37+/-7% on CT angiograms using a B30s and 25+/-9% on CT angiograms using a B60s. The mean CT attenuation in in-stent lumen was 347+/-55HU on CT angiograms using a B30s and 295+/-46HU on CT angiograms using a B60s. The ALN and CT attenuation within the stented vessels between CT angiograms using a B30s and a B60s was significant (p<0.01). CONCLUSIONS: 16-slice MDCT using a sharp kernel allows good visualization of the stented vessels and is useful in the assessment of vertebral artery stent patency after stent placement.

Polyvinyl alcohol embolization adjuvant to oily chemoembolization in advanced hepatocellular carcinoma with arterioportal shunts.

OBJECTIVE: To assess the feasibility and safety of polyvinyl alcohol (PVA) embolization adjuvant to transarterial oily chemoembolization (P-TACE) in advanced hepatocellular carcinoma (HCC) with arterioportal shunts (APS). MATERIALS AND METHODS: Nineteen patients who underwent PVA embolization for APS before a routine chemoembolization (TACE) procedure were retrospectively reviewed. 10 of these 19 patients underwent follow-up TACE or P-TACE after P-TACE (Group A), but nine patients underwent only initial P-TACE because of progression of HCC and/or underlying liver cirrhosis (Group B). Hepatic function tests, APS grades, and portal flow directions were evaluated before and after P-TACE sessions. Complications after procedures and survival days were also evaluated. RESULTS: In group A, APS grade was improved in eight patients and five of six patients with hepatofugal flow showed restored hepatopetal flow postoperatively. No immediate complication was developed in either group. Transient hepatic insufficiency developed in eight (42.1%) of 19 patients after P-TACE, and seven (87.5%) of these eight recovered within two weeks under conservative care. The mean and median survival time all study subjects was 280 days and 162 days. CONCLUSION: P-TACE is feasible and safe in advanced HCC patients with APS.

Acute and repeated inhalation lung injury by 3-methoxybutyl chloroformate in rats: CT-pathologic correlation.

OBJECTIVES: To investigate the acute and repeated pulmonary damage in Sprague-Dawley rats caused by the inhalation of 3-methoxybutyl chloroformate (3-MBCF) using computed tomography (CT), and to correlate these results with those obtained from a pathological study. METHODS: Sixty, 7-week-old rats were exposed to 3-MBCF vapor via inhalation (6 h/day) for 1 day (N=20), 3 days (N=20), and 28 days (5 days/week) (N=20) using whole body exposure chambers at a concentration of 0 (control), 3, 6 and 12 ppm. CT examinations including densitometry and histopathologic studies were carried out. For the follow-up study, the rats exposed for 3 days were scanned using CT and their pathology was examined at 7, 14, and 28 days. RESULTS: There was a significant decrease in the parenchymal density in the groups exposed to the 3-MBCF vapors for 1 day at 3 ppm (p=0.022) or 6 ppm (p=0.010), compared with the control. The parenchymal density of the rats exposed to 12 ppm was significantly higher. The pathological findings in this period, the grades of vascular congestion, tracheobronchial exfoliation, and alveolar rupture were significant. In the groups exposed for 3 days, there was a large decrease in the parenchymal density with increasing dose (control: -675.48+/-32.82 HU, 3 ppm: -720.65+/-34.21 HU, 6 ppm: -756.41+/-41.68 HU, 12 ppm: -812.56+/-53.48 HU) (p=0.000). There were significant density differences between each dose in the groups exposed for 28 days (p=0.000). The CT findings include an irregular lung surface, areas of multifocal, wedge-shaped increased density, a heterogeneous lung density, bronchial dilatation, and axial peribronchovascular bundle thickening. The histopathology examination revealed the development of alveolar interstitial thickening and vasculitis, and an aggravation of the mainstem bronchial exudates and bronchial inflammation. The alveolar wall ruptures and bronchial dilatation became severe during this period. On the follow-up study, the groups exposed for 3 days showed diffusely increased parenchymal density on the 7 days study, but the lung densities were lower at 14 and 28 days than at 3 days. In the rats exposed to lowest concentration, the pulmonary parenchymal density and pathologic findings rapidly returned to normal within 1 week. CONCLUSIONS: Decreased parenchymal density of the lung was a common CT finding in acute and repeated inhalation injury. The air accumulation is believed to be the results of tracheolaryngeal inflammatory edema, bronchial dilatation, and alveolar rupture from the early period.