Bull’s-eye pattern of pancreatic-duct stones on multidetector computed tomography and gene-mutation-associated pancreatitis (GMAP)

Purpose

This study prospectively assessed whether the presence of a bull??s-eye pattern of pancreatic-duct stones on multidetector computed tomography (MDCT) correlated with gene-mutation-associated pancreatitis (GMAP) and whether other signs suggestive of GMAP can be detected with MDCT.

Materials and methods

Forty-seven patients with chronic calcific pancreatitis underwent genetic testing for CFTR, SPINK1 and PRSS1 mutations and an MDCT scan of the abdomen. Qualitative analysis assessed the presence or absence of pancreatic-duct stones with bull??s-eye appearance. Quantitative analysis included the number and maximum diameter of stones and the diameter of the main pancreatic duct.

Results

Fifteen of 47 patients (32%) were positive for gene mutations (GMAP patients). The bull??s-eye pattern was found in 10/15 patients (67%) with GMAP and in 4/32 (12%) patients with chronic pancreatitis not associated with GMAP (NGMAP; p<0.0001). The mean diameter of duct stones was 15 mm in patients with GMAP and 10 mm in patients with NGMAP (p<0.04).

Conclusions

The presence of duct stones with a bull??s-eye pattern correlates with GMAP. Duct stones with diameter ??15 mm are another sign suggestive of GMAP.     

Multifocal branch-duct intraductal papillary mucinous neoplasms (IPMNs) of the pancreas: magnetic resonance (MR) imaging pattern and evolution over time

Purpose

The aim of our study was to follow the evolution over time of multifocal intraductal papillary mucinous neoplasms (IPMN) of the pancreatic duct side branches by means of magnetic resonance imaging (MRI).

Materials and methods

A total of 155 patients with multifocal IPMN of the side branches were examined with MRI and MR cholangiopancreatography (MRI/MRCP). Inclusion criteria were patients with ≥2 dilated side branches involving any site of the parenchyma; presence of communication with the main pancreatic duct and previous investigations by MRI/MRCP within at least six months. Median follow-up was 25.8 months (range, 12–217). Patients with a follow-up period shorter than 12 months (n=33) and those with a diagnosis of multifocal IPMN of the side branches without any follow-up (n=14) were excluded from the study. The final study population thus comprised 108 patients. A double, quantitative and qualitative, analysis was carried out. The quantitative image analysis included: number of dilated side branches in the head-uncinate process and body-tail; maximum diameter of lesions in the head-uncinate process; maximum diameter in the body-tail; maximum diameter of the main pancreatic duct in the head and body-tail. The qualitative image analysis included: presence of malformations or anatomical variants of the pancreatic ductal system; site of the lesions (head-uncinate process, body-tail, ubiquitous, bridge morphology); presence of gravity-dependent intraluminal filling defects; presence of enhancing mural nodules.

Results

At diagnosis, the mean number of cystic lesions of the side branches was 7.09. The mean diameter of the cystic lesions was 13.7 mm. The mean diameter of the main pancreatic duct was 3.6 mm. At follow-up, the mean number of cystic lesions was 7.76. The mean diameter of the cystic lesions was 13.9 mm. The mean diameter of the main pancreatic duct was 3.7 mm. Intraluminal filling defects in the side branches were seen in 18/108 patients (16.6%); enhancing mural nodules were seen in 3/108 patients (2.7%).

Conclusions

Multifocal IPMN of the branch ducts shows a very slow growth and evolution over time. In our study, only 3/108 patients showed mural nodules which, however, did not require any surgical procedure, indicating that careful nonoperative management may be safe and effective in asymptomatic patients.     

Classification of noncalcified coronary atherosclerotic plaque components on CT coronary angiography: impact of vascular attenuation and density thresholds

Purpose

The authors assessed the effect of vascular attenuation and density thresholds on the classification of noncalcified plaque by computed tomography coronary angiography (CTCA).

Materials and methods

Thirty patients (men 25; age 59±8 years) with stable angina underwent arterial and delayed CTCA. At sites of atherosclerotic plaque, attenuation values (HU) were measured within the coronary lumen, noncalcified and calcified plaque material and the surrounding epicardial fat. Based on the measured CT attenuation values, coronary plaques were classified as lipid rich (attenuation value below the threshold) or fibrous (attenuation value above the threshold) using 30-HU, 50-HU and 70-HU density thresholds.

Results

One hundred and sixty-seven plaques (117 mixed and 50 noncalcified) were detected and assessed. The attenuation values of mixed plaques were higher than those of exclusively noncalcified plaques in both the arterial (148.3±73.1 HU vs. 106.2±57.9 HU) and delayed (111.4±50.5 HU vs. 64.4±43.4 HU) phases (p<0.01). Using a 50-HU threshold, 12 (7.2%) plaques would be classified as lipid rich on arterial scan compared with 28 (17%) on the delayed-phase scan. Reclassification of these 16 (9.6%) plaques from fibrous to lipid rich involved 4/30 (13%) patients.

Conclusions

Classification of coronary plaques as lipid rich or fibrous based on absolute CT attenuation values is significantly affected by vascular attenuation and density thresholds used for the definition.     

Incidence for progression of hypervascular HCC in hypovascular hepatic nodules showing hyperintensity on gadoxetic acid-enhanced hepatobiliary phase in patients with chronic liver diseases

Purpose

The purpose of this study was to elucidate the incidence and risk factors for the progression of hyperintense nodules, observed in the hepatobiliary phase of gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid-enhanced magnetic resonance imaging (Gd-EOB-DTPA-enhanced MRI), to hypervascular hepatocellular carcinoma (HCC).

Materials and methods

Hypovascular nodules (n = 157) showing hyperintensity in the hepatobiliary phase of Gd-EOB-DTPA-enhanced MRI were examined in 41 patients. All patients underwent computed tomography (CT) during hepatic arteriography and CT during arterial portography within one month of Gd-EOB-DTPA-enhanced MRI. The incidence of progression to hypervascular or classical HCC was calculated using the Kaplan–Meier method.

Results

Tumor size was determined by univariate and multivariate analysis to be an important risk factor of hypervascularization (p = 0.041, odds ratio 1.135). The cumulative incidences of hypervascularization in hypovascular nodules showing hyperintensity on the hepatobiliary phase of Gd-EOB-DTPA-enhanced MRI were 2.4, 4.5, and 6.2 % at 12, 24, and 36 months, respectively. The incidence of hypervascularization was significantly increased in nodules >10 mm in diameter (p = 0.00035).

Conclusion

In patients with chronic liver disease, hypovascular nodules presenting as hyperintense in the hepatobiliary phase of Gd-EOB-DTPA-enhanced MRI and >10 mm in diameter have malignant potential for progression to hypervascular HCC and require careful management.     

Prospective study comparing two iodine concentrations for multidetector computed tomography of the pancreas

Purpose

The authors sought to determine the influence of two different iodine concentrations of nonionic contrast media (cm) on contrast enhancement in pancreatic computed tomography angiography (CTA).

Materials and methods

Sixty patients with clinically suspected or known pancreatic disease underwent pancreatic CTA. The patients were randomly assigned to group A (n=30) and group B (n=30). The contrast agent was injected with iodine concentrations of 400mgI/ml (Iomeron 400) in group A and 300mgI/ml (Iopamidol 300) in group B with the same total iodine dose (36 g). Arterial and portal venous phase contrast enhancement of the vessels, organs and pancreatic masses was measured, and blinded qualitative image assessment was performed by two expert radiologists.

Results

In the arterial and portal venous phase, the highly concentrated cm led to significantly greater enhancement in the abdominal main vessels, pancreas and pancreatic carcinoma than did the low concentrated cm. No statistically significant attenuation differences were measured between pancreatic carcinomas and the pancreatic parenchyma in the arterial and portal venous phase between group A and B. The overall trend for both readers was to assign higher scores to group A than group B.

Conclusions

The higher iodine concentration leads to greater contrast enhancement of abdominal vessels and organs in pancreatic CTA. Detection and demarcation of hypovascular pancreatic carcinoma was not found to be improved by the higher iodine concentration.     

慢性胰腺炎并发胆总管扩张的CT诊断

目的 提高对慢性胰腺炎并发胆总管扩张的知识。方法 对16例慢性胰腺炎并发胆总管扩张患者的CT图像进行分析。结果 16例中，胰头缩小8例，增大饱满6例，体积不变2例。轮廓不规则11例；胰实质不均15例；胰周脂肪间隙模糊12例；胆总管均扩张，直径在11mm～15mm之间的13例，15mm～20mm之间的3例；胰头段胆总管受压14例，胆总管狭窄2例。结论 慢性胰腺炎并发胆总管扩张的CT诊断并不困难，但在临床上应重视与其他中腹部疾病的鉴别。     

Assessment of left main coronary artery atherosclerotic burden using 64-slice CT coronary angiography: correlation between dimensions and presence of plaques

Purpose

The aim of this study was to correlate left main (LM) coronary artery dimensions with the presence of atherosclerosis by multidetector-row computed tomography (MDCT) coronary angiography (CA) and to assess coronary atherosclerotic plaques with a semiquantitative method.

Materials and methods

Sixty-two consecutive patients (41 men, mean age 60±11) with suspected coronary artery disease underwent 64-MDCT coronary angiography. LM dimensions (length, ostial and bifurcation diameters), quantitative [location, Hounsfield unit (HU) attenuation] and qualitative (composition, shape) analysis of plaques within the LM were performed. All patients underwent conventional CA.

Results

Thirty patients (mean age 55±10) without plaques in the LM presented the following average dimensions: length 10.6±6.1 mm, ostial diameter 5.5±0.7 mm, bifurcation diameter 4.9±0.9 mm. LM plaques (n=36) were detected in 32 patients (mean age 64±10) with the following LM average dimensions: length 11.3±4.0 mm, ostial diameter 6.0±1.2 mm and bifurcation diameter 6.0±1.2 mm. Plaques were calcified (40%, mean attenuation 742±191 HU), mixed (43%, mean attenuation 387±94 HU) or noncalcified (17%, mean attenuation 56±14 HU) and were frequently eccentric (77%). Age was significantly different in the two groups (p<0.05). LM diameters of patients with plaques were improved (p<0.05). A moderate correlation was found between the LM bifurcation diameter and the corresponding plaque area (r=0.56). Significant conventional CA lesions of the LM were present in just three patients (5%).

Conclusions

Increased LM diameters are associated with the presence of atherosclerosis. MDCT CA indicates relevant features of LM atherosclerotic burden, as rupture and subsequent thrombosis of vulnerable plaques may develop from lesions characterised as nonsignificant at conventional CA.     

Assessment of pulmonary melanoma metastases with 18F-FDG PET/CT: which PET-negative patients require additional tests for definitive staging?

Objectives

To determine, in patients with melanoma, the dependence of PET sensitivity on pulmonary metastasis size, and to determine patients who require further evaluation for definite staging.

Methods

Of 183 melanoma patients who underwent ¹⁸F-fluorodeoxyglucose PET/computed tomography (CT) for staging or follow-up between January 2008 and June 2011, 38 patients (18 women and 20 men; mean age 62.0?±?14.7?years) with one or more pulmonary metastases visible on CT were included in the retrospective study. Each pulmonary metastasis was rated as positive or negative on PET, and lesion size (maximum transverse diameter) was assessed on CT. PET sensitivity was calculated according to the lesions’ size, in 2-mm steps.

Results

A total of 181 pulmonary metastases were analysed. PET sensitivity was 7.9?% for lesions of 4–5?mm; 33.3?% for lesions of 6–7?mm; 56.8?% for lesions of 8–9?mm; 63.6?% for lesions of 10–11?mm; 100?% for lesions of 12–14?mm; and 100?% for lesions of at least 15?mm. The differences in sensitivity between the size groups were significant (P?<?0.001)

Conclusions

With current state-of-the-art PET/CT technology, additional tests are necessary for definitive staging of melanoma patients who have one or more PET-negative lung nodules less than 12?mm in diameter on expiratory CT.

Key Points

? PET cannot rule out malignancy in pulmonary nodules less than 12?mm on expiratory CT. ? Melanoma patients with PET-negative pulmonary nodules less than 12?mm require additional tests. ? Knowledge of these factors can help interpretation of PET and PET/CT findings.     

Gadoxetic acid-enhanced MRI for hepatocellular carcinoma and hypointense nodule observed in the hepatobiliary phase

Purpose

The aim of our study was to evaluate the diagnostic accuracy of gadoxetic acid-enhanced magnetic resonance (MR) imaging both in the detection of hepatocellular carcinoma (HCC) and precancerous lesions and in the assessment of their evolution.

Materials and methods

A retrospective study was undertaken on 56 patients with chronic liver disease and suspected liver lesions. We evaluated the number, size and signal intensity of the nodules on dynamic and hepatobiliary MR images. Follow-up studies were carried out every 3 months. Statistical analysis was performed using the Fisher’s exact test.

Results

A total of 120 nodules were identified in 41 patients. Of these, 92/120 nodules (76.6 %; mean diameter 18.4 mm) showed the typical HCC vascular pattern: 90/92 nodules appeared hypointense and 2/92 were hyperintense on hepatobiliary phase images. An additional 28/120 hypointense, nonhypervascular nodules (23.3 %; mean diameter 11 mm) were detected on hepatobiliary phase images, 15 of which showed hypointensity also on the equilibrium phase images. During the 3- to 12-month follow-up, 14/28 nodules (mean diameter 13.3 mm) developed the typical vascular pattern of HCC.

Conclusions

Gadoxetic acid-enhanced MR imaging is useful for detecting HCC as well as hypovascular nodules with potential progression to HCC. Lesions measuring more than 10 mm in diameter are at higher risk of developing into HCC (p = 0.0128).     

Contrast-enhanced ultrasonography (CEUS) immediately after percutaneous ablation of hepatocellular carcinoma

Purpose

This study evaluated the effectiveness of contrast-enhanced ultrasound (CEUS), performed immediately after percutaneous ethanol injection (PEI) or radiofrequency thermal ablation (RFTA), by comparing results with the computed tomography (CT) follow-up.

Materials and methods

Sixty-nine consecutive patients with a diagnosis of hepatocellular carcinoma (HCC) were included in this prospective study. All patients underwent PEI or RFTA. After treatment, three CEUS enhancement patterns were observed: isovascular, hypovascular and avascular, which were compared with the CT findings. Sensitivity of the avascular pattern at CEUS and effectiveness of the ablative procedures were evaluated and compared with the chi-square test.

Results

Ninety hypervascular HCCs, with a mean diameter of 2.6 cm (0.5–4.9 cm), underwent PEI (n=54) and RFTA (n=36). In the first group, CT identified complete necrosis in 28/54 (52%) lesions, 21 (75%) of which had avascular, one (4%) isovascular and six (21%) hypovascular patterns at CEUS. In the second group, CT showed complete necrosis in 31/36 (86%) lesions, all (100%) of which had a corresponding avascular pattern at CEUS. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy of the avascular pattern at CEUS compared with CT findings were 75%, 69%, 72%, 72% and 72% for PEI and 100%, 20%, 89%, 100% and 89%, for RFTA, respectively. A statistically significant difference (p<0.05) between the sensitivity of CEUS after PEI and after RFTA and between the necrosis obtained by RFTA and PEI were observed.

Conclusions

CEUS performed immediately after percutaneous ablation of hepatocellular carcinoma to evaluate treatment efficacy is compulsory in the case of RFTA but not for PEI.     

Percutaneous Transhepatic Removal of Bile Duct Stones: Results of 261 Patients

Purpose

To determine the effectiveness of percutaneous transhepatic removal of bile duct stones when the procedure of endoscopic therapy fails for reasons of anatomical anomalies or is rejected by the patient.

Methods

Between April 2001 and May 2010, 261 patients (138 male patients and 123 female patients; age range, 14–92 years; mean age, 64.6 years) with bile duct stones (common bile duct [CBD] stones = 248 patients and hepatolithiasis = 13 patients) were included in the study. Percutaneous transhepatic cholangiography was performed, and stones were identified. Percutaneous transhepatic balloon dilation of the papilla of Vater was performed. Then stones were pushed out into the duodenum with a Fogarty balloon catheter. If the stone diameter was larger than 15 mm, then basket lithotripsy was performed before balloon dilation.

Results

Overall success rate was 95.7%. The procedure was successful in 97.5% of patients with CBD stones and in 61.5% of patients with hepatolithiasis. A total of 18 major complications (6.8%), including cholangitis (n = 7), subcapsular biloma (n = 4), subcapsular hematoma (n = 1), subcapsular abscess (n = 1), bile peritonitis (n = 1), duodenal perforation (n = 1), CBD perforation (n = 1), gastroduodenal artery pseudoaneurysm (n = 1), and right hepatic artery transection (n = 1), were observed after the procedure. There was no mortality.

Conclusion

Our experience suggests that percutaneous transhepatic stone expulsion into the duodenum through the papilla is an effective and safe approach in the nonoperative management of the bile duct stones. It is a feasible alternative to surgery when endoscopic extraction fails or is rejected by the patient.     

Comparative diagnostic evaluation with MR cholangiopancreatography, ultrasonography and CT in patients with pancreatobiliary disease

Purpose

The aim of this study was to directly compare the results of magnetic resonance cholangiopancreatography (MRCP) with those of ultrasonography (US) and multislice computed tomography (MSCT) in the diagnosis of pancreaticobiliary diseases.

Materials and methods

A total of 70 patients (41 men, 29 women) aged 22-89 years were studied either before (n=59) or after cholecystectomy (n=11) for biliary lithiasis. Clinical signs and symptoms were jaundice (n=15), abdominal pain (n=37) and proven biliary lithiasis (n=18). MRCP was performed in all patients, whereas abdominal US was performed in 55 (group 1) and MSCT in 37 (group 2) patients. A regional evaluation of the main structures of the pancreaticobiliary system was performed: gallbladder and cystic duct, intra- and extrahepatic bile ducts and main pancreatic duct. Histology (n=27), biopsy (n=5), endoscopic retrograde cholangiopancreatography (ERCP) (n=28) and/or clinical-imaging follow-up (n=10) were considered standards of reference. In particular, patients were classified as showing benign (n=47) or malignant (n=12) lesions or normal biliary anatomy (n=11).

Results

In group 1, the results of MRCP and US were concordant in the majority (92%) of cases; however, statistically significant discordance (p<0.01) was found in the evaluation of the extrahepatic ducts, with nine cases (16%) of middle-distal common bile duct stones being detected on MRCP only. In group 2, the results of MRCP and MSCT were also concordant in most cases (87%). However, findings were significantly discordant when the intra- and extrahepatic ducts were analysed, with seven (19%) and six (16%) cases, respectively, of lithiasis being detected on MRCP only (p<0.01 for both).

Conclusions

The results of our study confirm the diagnostic potential of MRCP in the study of the pancreaticobiliary duct system. In particular, the comparison between MRCP and US and MSCT indicates the superiority of MRCP in evaluating bile ducts and detecting stones in the common bile duct.     

CT of the extrahepatic bile ducts: wall thickness and contrast enhancement in normal and abnormal ducts

Recent reports have described thickening and enhancement of the extrahepatic bile duct wall on CT scans obtained after administration of IV contrast material. We undertook this study to establish parameters for the normal thickness and enhancement of the bile duct wall on CT, and to develop a differential diagnosis for thickening of the duct wall. Routine CT examinations of 100 patients without biliary disease were evaluated prospectively. The common hepatic duct and common bile duct could be visualized in 66% and 82% of cases, respectively; the walls of these ducts could be separately discerned in 59% and 52%. The mean thickness of the duct wall was 1 mm, with a maximal thickness of 1.5 mm. Wall enhancement was similar to (51%), slightly greater than (44%), or markedly greater than (5%) the enhancement of adjacent pancreatic parenchyma. A review of records covering a 5-year period identified 52 patients in whom CT showed thickening of the bile duct wall (greater than or equal to 2 mm). These patients could be categorized by seven underlying diseases, and analysis of the CT scans revealed four general patterns of thickening. Focal, concentric wall thickening in the distal common bile duct was associated with pancreatitis, pancreatic cancer, and common bile duct stones; focal, eccentric thickening tended to occur with cholangiocarcinoma and sclerosing cholangitis. Diffuse, concentric thickening was seen with acute cholangitis; diffuse, eccentric thickening was associated with oriental cholangiohepatitis and sclerosing cholangitis. Thickening of greater than 5 mm was seen only with cholangiocarcinoma. Enhancement of the duct wall in these groups varied and was of no predictive value. In summary, the extrahepatic bile ducts can be visualized in the majority of patients, and the normal duct wall should be 1.5 mm or less in thickness. Contrast enhancement of the duct wall occurs in patients without biliary tract disease and alone is predictive not predictive of pathology. Pancreatitis, pancreatic cancer, common bile duct stones, cholangiocarcinoma, sclerosing cholangitis, acute cholangitis, and oriental cholangiohepatitis are associated with thickening of the duct wall.     

Percutaneous Transhepatic Removal of Bile Duct Stones: Results of 261 Patients

Purpose

To determine the effectiveness of percutaneous transhepatic removal of bile duct stones when the procedure of endoscopic therapy fails for reasons of anatomical anomalies or is rejected by the patient.

Methods

Between April 2001 and May 2010, 261 patients (138 male patients and 123 female patients; age range, 14–92 years; mean age, 64.6 years) with bile duct stones (common bile duct [CBD] stones = 248 patients and hepatolithiasis = 13 patients) were included in the study. First, percutaneous transhepatic cholangiography was performed and stones were identified. Percutaneous transhepatic balloon dilation of the papilla of Vater was performed. Then stones were pushed out into the duodenum with a Fogarty balloon catheter. If the stone diameter was larger than 15 mm, then basket lithotripsy was performed before balloon dilation.

Results

Overall success rate was 95.7%. The procedure was successful in 97.5% of patients with CBD stones and in 61.5% of patients with hepatolithiasis. A total of 18 (6.8%) major complications, including cholangitis (n = 7), subcapsular biloma (n = 4), subcapsular hematoma (n = 1), subcapsular abscess (n = 1), bile peritonitis (n = 1), duodenal perforation (n = 1), CBD perforation (n = 1), gastroduodenal artery pseudoaneurysm (n = 1), and right hepatic artery transection (n = 1), were seen after the procedure. There was no mortality.

Conclusion

Our experience suggests that percutaneous transhepatic stone expulsion into the duodenum through the papilla is an effective and safe approach in the nonoperative management of the bile duct stones. It is a feasible alternative to surgery when endoscopic extraction fails or is rejected by the patient.     

Incidental lung nodules on CT examinations of the abdomen: Prevalence and reporting rates in the PACS era

Objectives

To retrospectively evaluate prevalence, reporting rates and clinical implications of incidental pulmonary nodules detected in multidetector computed tomography (MDCT) abdominal studies.

Materials and methods

Abdominal MDCT studies of 243 consecutive patients, 94 of whom had a history of cancer, were evaluated. Lung bases included in the scan were reviewed on a PACS workstation with different window settings and post-processing techniques. Nodules were classified according to their density (calcified, solid noncalcified, non-solid, part-solid) and size (<4 mm; 4-6 mm; 6-8 mm; >8 mm). The study findings were compared with the corresponding radiologic reports. Previous of following CT studies, when available from the PACS, were also reviewed to evaluate changes in number and size of the detected nodules.

Results

An average of 8.2 cm of lung parenchyma was imaged in each patient. 213 noncalcified nodules (NCNs) were identified in 95 patients (39.1%) but only 8 patients (8.4%) had it mentioned in the final report. Comparison CT studies were available for 44 out of the 95 positive patients showing disappearance of the nodules in 2 cases, no interval change in 26 and progression in size and/or number in 16 patients, in whom a final diagnosis of metastasis or primary lung cancers was achieved.

Conclusion

Radiologists tend to overlook lung portions on abdominal CT studies. Underreporting may affect patient care and have medico-legal implications since images are permanently stored in digital format on PACS and CD-ROMs. Management of the discovered nodules should be tailored to the clinical situation of the patient, and particular care should be reserved to patients with oncologic history.     

Preoperative computed tomography of the chest in lung cancer patients: the predictive value of calcified lymph nodes for the perioperative outcomes of video-assisted thoracoscopic surgery lobectomy

Objectives

To determine the predictive value of identifying calcified lymph nodes (LNs) for the perioperative outcomes of video-assisted thoracoscopic surgery (VATS).

Methods

Fifty-six consecutive patients who underwent VATS lobectomy for lung cancer were included. We evaluated the number and location of calcified LNs on computed tomography (CT). We investigated clinical parameters, including percentage forced expiratory volume in 1 s (FEV₁%), surgery duration, chest tube indwelling duration, and length of hospital stay. We performed linear regression analysis and multiple comparisons of perioperative outcomes.

Results

Mean number of calcified LNs per patient was 0.9 (range, 0–6), mostly located in the hilar-interlobar zone (43.8 %). For surgery duration (mean, 5.0 h), FEV₁% and emphysema severity were independent predictors (P?=?0.010 and 0.003, respectively). The number of calcified LNs was an independent predictor for chest tube indwelling duration (P?=?0.030) and length of hospital stay (P?=?0.046). Mean duration of chest tube indwelling and hospital stay was 8.8 days and 12.7 days in no calcified LN group; 9.2 and 13.2 in 1 calcified LN group; 12.8 and 19.7 in ≥2 calcified LNs group, respectively.

Conclusions

The presence of calcified LNs on CT can help predict more complicated perioperative course following VATS lobectomy.

Key Points

? Preoperative chest CT can help predict perioperative outcome following video-assisted thoracoscopic surgery. ? Calcified lymph nodes should be assessed on CT to predict perioperative outcome. ? Multiple calcified LNs are associated with longer chest drainage. ? Hospital stay appears longer in patients with more calcified lymph nodes.     

The renal parenchymal stone: a benign calcified renal mass

Five patients are described, each with a densely calcified solitary mass in a peripheral location in the kidney. There was exophytic projection of the calcification in 4 cases. Three lesions were so completely calcified as to be regarded as stones. The bulk of the lesion was calcified in the 2 other cases, in which the noncalcified portion was either avascular or hypovascular. In no case was there evidence of a soft-tissue mass extending beyond the confines of the calcification. Pathologic correlation in 1 case showed only calcification in association with some renal scarring, and in a second case demonstrated an old organized and calcified abscess. Long-term follow-up in the other 3 cases has demonstrated complete stability without evidence of tumor. All cases are believed to represent examples of calcified renal parenchymal scars, resulting from old granulomatous disease, renal abscess, or hematoma. We propose that these lesions be regarded as solitary renal parenchymal stones without malignant potential, rather than calcified masses. The significance of the findings for patient management are discussed.     

Gallstone dissolution in methyl tert-butyl ether after mechanical fragmentation: in vitro study

Twenty sets of three gallstones matched for weight and appearance were selected from 20 surgically resected human gallbladders to test the effect of intracorporeal mechanical fragmentation on gallstone dissolution with methyl tert-butyl ether in vitro. One stone from each set was fragmented by a mechanical lithotriptor and then treated with methyl tert-butyl ether, and one was used as control and was treated intact. The third stone was analyzed for its density pattern on CT and biochemically for its cholesterol and calcium content. On the basis of CT appearance, the stones were classified as noncalcified, partially calcified, or heavily calcified. Mechanical fragmentation reduced dissolution time by 25-69% (mean +/- SD, 44 +/- 16%) for the noncalcified stones and by 20-42% (mean +/- SD, 30 +/- 8%) for the partially calcified stones. No significant reduction was observed for the heavily calcified stones. The degree of reduction was inversely related to maximal stone density (r = -.72) and was independent of its pattern of calcification. This study shows that mechanical fragmentation is effective in accelerating gallstone chemolysis by methyl tert-butyl ether for noncalcified and partially calcified but not for heavily calcified stones.     

The renal parenchymal stone: A benign calcified renal mass

Five patients are described, each with a densely calcified solitary mass in a peripheral location in the kidney. There was exophytic projection of the calcification in 4 cases. Three lesions were so completely calcified as to be regarded as stones. The bulk of the lesion was calcified in the 2 other cases, in which the noncalcified portion was either avascular or hypovascular. In no case was there evidence of a soft-tissue mass extending beyond the confines of the calcification. Pathologic correlation in 1 case showed only calcification in association with some renal scarring, and in a second case demonstrated an old organized and calcified abscess. Long-term follow-up in the other 3 cases has demonstrated complete stability without evidence of tumor. All cases are believed to represent examples of calcified renal parenchymal scars, resulting from old granulomatous disease, renal abscess, or hematoma. We propose that these lesions be regarded as solitary renal parenchymal stones without malignant potential, rather than calcified masses. The significance of the findings for patient management are discussed.     

Autoimmune pancreatitis: Assessment of the enhanced duct sign on multiphase contrast-enhanced computed tomography

Purpose

To assess the usefulness of the computed tomography (CT) finding of main pancreatic duct (MPD) wall enhancement, termed the “enhanced duct sign”, for diagnosis of autoimmune pancreatitis (AIP) in comparison with diagnosis of pancreatic carcinoma and chronic pancreatitis.

Materials and methods

Two radiologists independently evaluated the presence or absence of the enhanced duct sign on multiphase contrast-enhanced CT in patients with AIP (n = 55), pancreatic carcinoma (n = 50), and chronic pancreatitis (n = 50). The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of AIP were calculated. In patients demonstrating the enhanced duct sign, additional findings were evaluated by consensus.

Results

The enhanced duct sign was more frequently observed in patients with AIP (37/55, 67%) than in patients with pancreatic carcinoma (5/50, 10%) or chronic pancreatitis (0/50, 0%) (P < 0.05). The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of the finding were 0.67, 0.95, 0.85, 0.88, and 0.84, respectively. In AIP, the lumen within the enhanced duct was completely or partially invisible in 29 of 37 (78%) patients, and the enhanced duct was observed within the affected pancreatic parenchyma in 35 of 37 (95%) patients. In pancreatic carcinoma, the lumen within the enhanced duct was visible in all patients (5/5, 100%), and the enhanced duct was observed downstream of the tumor (5/5, 100%).

Conclusion

The enhanced duct sign is highly specific of AIP.