Comparison of LI-RADS with other non-invasive liver MRI criteria and radiological opinion for diagnosing hepatocellular carcinoma in cirrhotic livers using gadoxetic acid with histopathological explant correlation.

AIM: To establish the diagnostic accuracy of the Liver Imaging Reporting and Data System (LI-RADS) for hepatocellular carcinoma (HCC) and compare its performance to that of international criteria from European Assofor the Study of the Liver (EASL), Japan Society of Hepatology (JSH), Asian Pacific Association for the Study of the Liver (APASL), and Organ Procurement and Transplantation Network (OPTN), and to the reporting radiologist's overall opinion regarding the probability of a nodule being a HCC by correlating with a histological diagnosis from whole liver explants. MATERIALS AND METHODS: The present single-centre, retrospective review selected participants based on the following criteria: adults (≥18 years) listed for liver transplantation in 2014/2015, with liver cirrhosis at the time of magnetic resonance imaging (MRI) with hepatocyte specific contrast agent, and at least one liver lesion ≥10 mm on MRI with histology from subsequent liver explant for comparison. Each lesion was assessed against international criteria and given a "radiologist opinion" score of 1-5 (1 = definitely benign, 5 = definitely HCC). RESULTS: Total 268 patient records were reviewed, with 105 eligible lesions identified from 47 patients. Median lesion size was 15.5 mm (range 10-68 mm). Sensitivity (%), specificity (%), and positive predictive value (PPV; %) for LI-RADS LR5 was 45, 89, and 89, for LI-RADS LR4+5 + TIV was 61, 80, and 86, for EASL was 44, 86 and 86, for JSH/APASL was 64, 81, and 87, for OPTN was 36, 90, and 88, and for "radiologist impression" of probably or definitely HCC was 79, 79, and 88 respectively. CONCLUSIONS: MRI has moderate sensitivity and good specificity for the diagnosis of HCC with considerable variation depending on criteria used. OPTN criteria have the best specificity, but low sensitivity. "Radiologist opinion" gives highest overall accuracy with increases in sensitivity and reduction in specificity when compared to the imaging criteria.

Variation in referral practice for patients with colorectal cancer liver metastases.

BACKGROUND: Half of patients with colorectal cancer develop liver metastases. There remains great variability between hospitals in rates of liver resection for colorectal cancer liver metastases (CLM). This study aimed to determine how many patients with potentially resectable CLM are not seen by specialist liver surgeons. METHODS: Patients presenting with new CLM in a cancer network consisting of a tertiary centre and seven attached hospitals were studied prospectively over 12 months. Data were collected retrospectively for patients who did not have a complete data set. Outcomes for patients referred to the liver tertiary centre were collated. The radiology of tumours deemed inoperable by the local colorectal specialist teams was reviewed by specialist liver surgeons and radiologists. RESULTS: In total, 631 patients with CLM were assessed. Prospective data were complete for 241 patients, and 64 (26.6 per cent) of these were referred to the specialist liver team for consideration of resection. No decision was documented for 16 patients (6.6 per cent). Of those not referred, 30 (18.6 per cent) were deemed unfit or refused and 131 (81.4 per cent) were thought inoperable. Referral rates varied between hospitals (13-43.6 per cent). Of 131 patients deemed fit but inoperable by the colorectal specialist teams, 38 (29.0 per cent) were deemed operable and 20 (15.3 per cent) had equivocal imaging when assessed retrospectively by liver specialists. In total, 142 of the 631 patients were referred to liver specialists for consideration of treatments, and 107 (75.4 per cent) treated with curative intent. CONCLUSION: A considerable number of patients with potentially resectable CLM are not assessed by specialist liver teams. Improved referral rates could greatly improve resection rates for CLM, which may improve outcomes for patients with colorectal cancer.

Diffusion-weighted MRI of the liver-Interpretative pearls and pitfalls.

Diffusion-weighted magnetic resonance imaging (DW MRI) is an established technique in neuroradiology and more recently has emerged as a useful adjunct to various oncological applications of MRI. It has an expanding role in the evaluation of liver lesions, offers higher detection rates for small lesions, and can increase confidence in differentiating between benign and malignant lesions. Other applications include assessment of tumour response to therapy, differentiating tumour from bland thrombus, and assessment of liver fibrosis. DW sequences can be performed on most modern MRI machines with relative ease, in a short time period and without the need for contrast medium. DW MRI can be of value in the detection and characterization of hepatic lesions but there are pitfalls, which can potentially cause interpretative difficulty. This article will review the rationale for DW MRI in liver imaging, demonstrate the clinical utility of the technique in a spectrum of hepatic diseases, and illustrate key interpretative pearls and pitfalls.

Influenza control can be achieved in a custodial setting: pandemic (H1N1) 2009 and 2011 in an Australian prison.

OBJECTIVES: Information on the effectiveness of interventions regarding control in closed institutional settings, including prisons, is limited. This study gathered evidence relating to influenza control in an Australian prison. STUDY DESIGN: This study built on a 2009 H1N1 outbreak investigation at the Alexander Maconochie Centre (AMC) in the Australian Capital Territory (ACT). METHODS: Influenza surveillance data, ACT 2010 Inmate Health Survey data, New South Wales 2001 and 2009 Inmate Health Survey data, ACT Department of Corrective Services administrative data, and ACT Health clinical data were analysed. RESULTS: In 2011, the AMC was exposed to influenza virus, resulting in a single case. Public health activities included exclusion of symptomatic cases from the health facility, isolation of cases, and quarantine of contacts. Contact between prisoners and the ACT community was maintained; the AMC detainee visitor rate was one visitor per prisoner every 10 days. CONCLUSIONS: The rehabilitative benefits of human contact for AMC detainees were not compromised during the surveillance period, despite the potential that a higher visitor rate may suggest. This highlights some features of the AMC which make its operational context different from many other correctional settings, but gives some indication of how good public health practice supports human rights.

Hilar cholangiocarcinoma: MR correlation with surgical and histological findings.

AIM: To evaluate magnetic resonance cholangiography (MRC) with high-resolution dynamic gadolinium-enhanced magnetic resonance imaging (MRI) in determining the imaging features of hilar cholangiocarcinoma that relate to tumour extent and influence resectability. MATERIALS AND METHODS: Twenty-six patients that underwent resection were reviewed. Tumour location and extent, lobar atrophy, the degree of portal vein and hepatic artery involvement were recorded. The findings were correlated with surgical and histopathological findings. RESULTS: Biliary assessment was concordant in 14 and discordant in eight of 14 stented and four of 12 non-stented patients. In 63/82 veins and 43/74 arteries results were fully concordant. The mean sensitivity, specificity, positive and negative predictive values (PPV, NPV) in predicting involvement of the main portal vein (MPV) at surgery were 83.3, 100, 100, and 92.5%; of the left main branch of the portal vein (LPV) were 100, 91.6, 93.3, and 100%; and of the right branch of the portal vein (RPV) were 87.5, 100, 100, and 87.5%. The sensitivity, specificity, PPV and NPV of MRI in determining histological involvement of the MPV was 75, 90.9, 60, and 92.5%; 100, 73.3, 73, and 100% for the LPV, and 100, 66.6, 42.8, and 100% for the RPV, respectively. CONCLUSION: MRC with high-resolution dynamic gadolinium-enhanced MRI is effective in determining tumour extent and vascular involvement, but prior stenting may lead to overestimation.

Effect of slice thickness on liver lesion detection and characterisation by multidetector CT.

The purpose of our study was to compare the effectiveness of 3.2 mm, 5 mm and 7.5 mm slice thicknesses in the detection and characterisation of liver lesions found on CT in patients with known or suspected malignant disease. 110 patients underwent portal phase imaging using four-slice MDCT. Two blinded observers independently read hard copy images at each slice thickness. The size and location of each lesion detected was recorded by each observer on a diagram of liver segmental anatomy. Each lesion was characterised as benign, malignant or indeterminate in nature. A diagnostic confidence score was allocated for each lesion on a scale of 1-4. The pathology or behaviour of lesions was assessed using surgery with intra-operative ultrasound (IOUS) and histology, or interval imaging with MRI, CT, or sonography. 294 lesions were detected, 64 (22%) of which were malignant. Both observers detected significantly more lesions on the 3.2 mm versus 7.5 mm slice thickness (p < 0.0001). Both observers detected more malignant lesions on 3.2 mm and 5 mm slice thicknesses versus 7.5 mm. As slice thickness decreased there was a significant increase in the sensitivity of malignant lesion detection for observer 1 (p < 0.001) and borderline significance for observer 2 (p = 0.07). As slice thickness decreased the proportion of lesions characterised as indeterminate by both observers fell. With thinner slices, both detection and characterisation of liver lesions were improved. A slice thickness no greater than 5 mm should be used to maximise both detection and correct characterisation of liver lesions.

Case hepatic endometriosis: a continuing diagnostic dilemma.

BACKGROUND: Intraparenchymal endometriosis of liver is rare. It may present as liver tumour and the diagnosis is not usually established till after surgery. CASE OUTLINE: A 48-year-old postmenopausal woman presented with right upper quadrant pain and a cystic liver mass. Liver function tests and tumour markers (alphaFP, CEA, CA 19-9, and CA 125) were normal. Radiological imaging (USS, CT and MRI) suggested a thick walled cystic mass involving segments IV and VIII with complex intracystic septations. Frozen section at operation suggested a benign cystadenoma. The cyst was enucleated using a CUSA (Cavitron ultrasonic aspirator). The final histology confirmed endometriosis. DISCUSSION: Eleven cases of hepatic endometrioma have been reported and only four in postmenopausal women. Preoperative diagnosis poses a challenge and so far none of the cases have been diagnosed preoperatively. Surgery remains the treatment of choice. Accurate diagnosis at time of operation may avoid extensive liver surgery and its associated morbidity.

Granulomatous infiltration with replacement of liver parenchyma: first case report.

A 76-year-old man presented with fever, weight loss and abnormal liver function tests. Imaging demonstrated a diffusely abnormal liver, and a liver biopsy revealed a fibrosing granulomatous process infiltrating and replacing liver parenchyma. There was no clinical, radiological or laboratory evidence of autoimmune liver disease, sarcoidosis, lymphoma or tuberculosis. Treatment with steroids resulted in a remarkable resolution of the clinical symptoms and radiology. This is the first case of granulomatous infiltration of the liver replacing normal hepatic parenchyma.

Non-operative management of the primary tumour in patients with incurable stage IV colorectal cancer.

BACKGROUND: Excision of primary colorectal cancer associated with irresectable synchronous metastases confers high morbidity and mortality with uncertain benefit. METHODS: For patients with incurable stage IV colorectal cancer, minimally symptomatic primary tumours were left in situ and 5-fluorouracil-based chemotherapy was administered systemically. Primary tumour-specific complications and survival were monitored. RESULTS: There were 13 men and 11 women with primary tumours in the right colon (eight), transverse colon (one), sigmoid colon (eight) or rectum (seven). Eleven patients had metastases limited to the liver (liver replacement less than 25 per cent in one, 25-50 per cent in four and more than 50 per cent in six) and 13 patients had extrahepatic disease (lung or peritoneum). Four patients with sigmoid colon tumours developed bowel obstruction, which required an uncomplicated operation in two and deployment of colonic stents in two patients, at 1, 3, 12 and 20 months from diagnosis. Three further patients underwent right hemicolectomy for abdominal pain of uncertain aetiology, with poor symptomatic relief, and another had a potentially curative operation following disease downstaging. The overall median survival was 10.3 months with a 1-year actuarial survival rate of 44 per cent. CONCLUSION: A policy to defer resection of minimally symptomatic primary colorectal cancer is associated with a low risk of complications before death from progressive systemic disease.

Duplication of the vertebral artery: report of two cases and review of the literature.

Duplication of the vertebral artery is rare. We report two cases in which it was an incidental finding. In the first, duplication of the right vertebral artery was demonstrated by magnetic resonance angiography (MRA) and conventional angiography. The second patient had duplication of the right vertebral artery demonstrated by MRA. We discuss the origin of this abnormality, its radiological implications and its potential clinical significance are discussed.

Dual phase helical CT versus portal venous phase CT for the detection of colorectal liver metastases: correlation with intra-operative sonography, surgical and pathological findings.

AIM: To assess whether dual phase helical computed tomography (DPCT) of the liver improves the detection of colorectal liver metastases compared with portal venous phase (PVP) imaging alone. MATERIALS AND METHODS: DPCT was performed in 33 consecutive patients before laparotomy for resection of colorectal liver metastases. CT comprised 8-mm slice collimation with a pitch of 1 to 1.25; imaging was commenced 20-25 and 65-70 s after the start of injection of 150 ml of contrast medium at 5 ml/s to coincide with hepatic arterial phase (HAP) and PVP contrast enhancement, respectively. Four blinded observers independently reviewed the HAP, PVP and DPCT images recording the site and size of all lesions. Alternative-free response receiver operating characteristic (AFROC) methodology was used to analyse the results, which were correlated with surgery, intra-operative ultrasound and histology. RESULTS: The mean observer sensitivities for malignant lesion detection were 75.3% for DPCT, 69.7% for PVP imaging and 66.7% for HAP imaging alone. There was a statistically significant improvement in malignant lesion detection using DPCT when compared with PVP imaging alone (P < 0.05). The mean areas under the AFROC curves were 0.84 for DPCT and 0.82 for PVP (P < 0.03) imaging alone. CONCLUSION: The detection of colorectal liver metastases was marginally better with DPCT than with PVP imaging alone, but the discovery of additional lesions did not affect the management of any of the patients in this study.

Scleroderma "en coup de sabre": pathological evidence of intracerebral inflammation.

Linear scleroderma "en coup de sabre" (LScs) is associated with neurological complications, the pathogenesis of which is uncertain. A 27 year old woman is reported on who developed epilepsy and focal neurological signs in association with LScs. Brain MRI demonstrated predominantly ipsilateral relapsing and remitting grey and white matter lesions. Analysis of CSF and pathology obtained at brain biopsy provides evidence of an inflammatory process which may be amenable to immunosuppressive treatment.

Hepatocellular carcinoma in the cirrhotic liver: double-contrast MR imaging for diagnosis.

PURPOSE: To measure the sensitivity and accuracy of double-contrast magnetic resonance (MR) imaging for the diagnosis of hepatocellular carcinoma (HCC) in the cirrhotic liver. MATERIALS AND METHODS: Twenty-seven patients with MR features of dysplastic nodules and/or HCC were examined. T2-weighted spin-echo and T1-weighted gradient-echo imaging was performed before and after superparamagnetic iron oxide (SPIO) administration and immediately followed by T1-weighted gradient-echo imaging at 10, 40, and 120 seconds after bolus injection of a gadolinium-based contrast material. Nonenhanced, nonenhanced plus SPIO-enhanced, and nonenhanced plus SPIO-enhanced plus gadolinium-enhanced images were reviewed. Alternative-free response receiver operating characteristic (ROC) methodology was used to analyze the results, which were correlated with histopathologic findings after transplantation in 15 patients and at biopsy in 12. Lesions visualized with all three techniques were characterized as a dysplastic nodule or HCC, and ROC analysis was performed. RESULTS: For all observers, SPIO-enhanced MR imaging (mean accuracy, 0.76) was more accurate than nonenhanced MR imaging (mean accuracy, 0.64) (P <.04), and double-contrast MR imaging (mean accuracy, 0.86) was more accurate than SPIO-enhanced imaging (P <.05). Both types of lesions were correctly characterized with all three techniques, although observer confidence for lesion characterization was greatest with double-contrast MR imaging. CONCLUSION: Double-contrast MR imaging significantly improves the diagnosis of HCC compared with SPIO-enhanced and nonenhanced imaging (P <.01).

HIV and AIDS in aboriginal and Torres Strait Islander Australians: 1992-1998. The National HIV Surveillance Committee.

OBJECTIVE: To describe the epidemiological pattern of newly diagnosed HIV infection and AIDS among Indigenous Australians. DESIGN AND SETTING: National surveillance for newly diagnosed HIV infection and AIDS in Australia. Information on Indigenous status was sought at HIV/AIDS notification in all State/Territory health jurisdictions, except the Australian Capital Territory, and Victoria before June 1998. MAIN OUTCOME MEASURES: Number of people with newly diagnosed HIV per year and population rate of HIV diagnosis; demographic characteristics of people with HIV and AIDS diagnoses by Indigenous status. RESULTS: From 1992 to 1998, 127 Indigenous Australians were newly diagnosed with HIV infection and 55 were diagnosed with AIDS. The population rate of HIV diagnosis among Indigenous Australians (5.23/100,000 per year) was similar to that among non-Indigenous Australians (5.51/100,000 per year). The annual number of HIV diagnoses among Indigenous people was relatively stable, but among non-Indigenous people it declined steadily over time. A higher proportion of Indigenous people diagnosed with HIV were women (26.8% v 8.9%; P < 0.001). Although male homosexual contact was the predominant source of exposure for both Indigenous (46.7%) and non-Indigenous (75.0%) people with HIV infection, exposure by heterosexual contact (36.7% v 15.3%; P < 0.001) was reported more frequently among Indigenous people. CONCLUSION: Although HIV incidence was similar among Indigenous and non-Indigenous Australians, the lack of a recent decline in incidence and the higher proportion of Indigenous people exposed to HIV by heterosexual contact indicate the need to intensify interventions to prevent HIV transmission among Indigenous people.

MRI of liver: a comparison of CNR enhancement using high dose and low dose ferumoxide infusion in patients with colorectal liver metastases.

The purpose of this study was to compare the effects of high dose (HD) and low dose (LD) ferumoxides infusions on lesion-to-liver contrast-to-noise ratio (CNR) using four different T(2)-weighted MR sequences. Seventy-three patients with known colorectal liver metastases underwent T(2)-weighted fast spin echo (FSE) imaging before and after ferumoxides. After ferumoxides, T(2)-weighted dual echo (DE) and T(2)-weighted GRE FLASH images were also obtained. To evaluate the relationship between TE length and lesion-to-liver CNR, the same FLASH sequence was repeated in 18 LD patients after lengthening the TE. Ferumoxides was administered at a dose of 15 micromol/kg (HD) and 7.5 micromol/kg (LD) in 45 and 28 patients, respectively. The effects of HD and LD ferumoxides infusions were measured as the percentage signal intensity change (PSIC) in the liver and lesions, lesion-to-liver CNR and the change in lesion-to-liver CNR (DeltaCNR). In both LD and HD groups, all CNR values obtained after SPIO were significantly greater than those observed with unenhanced FSE (p < 0.01). There was no significant difference between the mean CNR values obtained with either dose for any sequence. With the FLASH sequence, CNR increased progressively with longer TE. At the longest TE of 26 ms, mean CNR was higher than that recorded with any of the other sequences. Although mean liver PSIC was significantly greater in the HD group than in the LD group (p < 0.01) because the mean lesion PSIC was also greater in the HD group, the mean DeltaCNR after ferumoxides was not significantly different in the two groups. LD SPIO enhanced MR significantly increases lesion-to-liver CNR compared with unenhanced images. At 1. 0 T, HD and LD ferumoxides infusions produce comparable lesion-to-liver CNR. Our results suggest that at 1.0 T ferumoxides may be administered at a dose of 7.5 micromol/kg without loss of image quality.

Hepatic lesion detection after superparamagnetic iron oxide enhancement: comparison of five T2-weighted sequences at 1.0 T by using alternative-free response receiver operating characteristic analysis.

PURPOSE: To compare the accuracy of five T2-weighted sequences in the detection of liver lesion at magnetic resonance (MR) imaging after superparamagnetic iron oxide (SPIO) enhancement. MATERIALS AND METHODS: Forty-nine candidates for hepatic resection with known coloretal metastases were examined. Before SPIO enhancement, fast spin-echo (SE) images were obtained. After enhancement, the same fast SE sequence and long; TR/short TE, short TE, long TR/TE, and T2-weighted fast low-angle shot (FLASH) sequences were used. All images were viewed independently by four observers who were blinded to the results of the other imaging sequences, the results of the other observers, and the findings at surgery and histopathologic examination. Four weeks after the initial reading, the combined long TR/short TE and long TR/TE dual-echo images were also viewed as an additional set. The alternative free response receiver operating characteristic (ROC) method was used to analyze the results, which were correlated with findings at surgery, intraoperative ultrasonography, and histopathologic examination. RESULTS: Irrespective of lesion size, the accuracy of all sequences after enhancement was significantly greater than that of the nonenhanced fast SE sequence (P < .01). Dual-echo and FLASH sequences were significantly more accurate than the enhanced fast SE sequence (P < .03 or P < .02, respectively). For all lesions, lesions smaller than 1 cm, and lesions 1 cm or larger, mean accuracies were as follows: dual-echo, 0.75, 0.54, and 0.93; FLASH, 0.75, 0.54, and 0.95; and enhanced fast SE, 0.72, 0.49, and 0.92. CONCLUSION: At 1.0 T, dual-echo and FLASH sequences are the most accurate pulse sequences after SPIO enhancement.