Postoperative spine complications

Imaging of the postoperative spine is common, although it remains a difficult task for radiologists. This article presents an overview of common surgical approaches and spinal hardware, and specific complications that may be associated with each procedure. In addition, expected postoperative changes and complications that are common among procedures, with their differential diagnosis and imaging features, are discussed.

Expression of EpCAM increases in the hepatitis B related and the treatment-resistant hepatocellular carcinoma

Increasing evidence supports the important role of cancer stem cells (CSCs). Many reports suggest that epithelial cell adhesion molecule (EpCAM) is a useful marker for cancer stem cells in hepatocellular carcinoma (HCC). To elucidate the mechanisms of cancer stem cells, the development of specific molecular targeted drugs has become very important. In the present study, we examined the EpCAM expression pattern and its characteristic expression in resected HCC. We studied the drug resistance of EpCAM expression cells. EpCAM expression was detected significantly more frequently with hepatitis B virus (HBV) than with other etiologies. In HCC resection patients who had received prior treatment (transcatheter arterial embolization or hepatic arterial infusion chemotherapy), EpCAM was strongly expressed. In particular, very strong expression was observed after hepatic arterial infusion chemotherapy. The PLC/PRF/5 human HCC cell line expressed bimodal EpCAM, and EpCAM-positive cells had CSC cell potency. The EpCAM expression in EpCAM-positive cells increased significantly by treatment with cisplatin. EpCAM-positive cells showed better viability than EpCAM-negative cells when treated with ciplatin. Collectively, our results suggest that cancer stem cells are highly expressed in hepatitis B and have potential anticancer drug resistance.

Intracranial primary dural diffuse large B-cell lymphoma successfully treated with chemotherapy

Diffuse large B-cell lymphoma (DLBCL) presented as a primary dural lesion is an extremely rare entity, which may be misdiagnosed as meningioma. Patients with symptomatic meningioma are usually treated with tumor resection. The five previously described cases of intracranial dural DLBCL were treated with surgery followed by chemotherapy and/or radiotherapy, with a favorable outcome, but with potential sequels. We reported the first case of DLBCL, presented as a primary dural lesion, successfully treated with chemotherapy only in a 52-year-old woman presented in October 2011 with rapidly progressive headaches, nausea and vomiting. Magnetic resonance imaging of the brain and head computed tomography showed a lesion en plaque in the right parieto-occipital region, tracking the dura matter, and osteolytic lesions. The patient underwent an open tumor biopsy, and the diagnosis of DLBCL was established. The patient received dexamethasone, cisplatin and cytarabine (DHAP) followed by methotrexate plus cytarabine, and obtained a durable complete response. Thus, intracranial dural DLBCL must be considered in differential diagnosis of meningeal lesions, particularly when a rapid progression of symptoms and osteolytic lesions are present, because an early diagnosis and rapid initiation of treatment, even though with chemotherapy, is associated with favorable outcome.

Microembolic signals detected with transcranial doppler sonography differ between symptomatic and asymptomatic middle cerebral artery stenoses in Northeast China

Although microembolus monitoring has been widely used for ischemic cerebrovascular disease, the clinical significance of microembolic signal (MES) in asymptomatic middle cerebral artery (MCA) stenosis remains unclear. We aim to investigate the frequency of MES and the value of MES in predicting ischemic stroke secondary to asymptomatic MCA stenosis. From June 2011 to December 2012, microembolus monitoring was performed in 83 asymptomatic and 126 symptomatic subjects. By comparing the demographics and risk factors between the symptomatic and asymptomatic subjects, we found that the ratio of male sexuality and smoking history differed (101/126 vs 43/83, and 88/126 vs 38/83, respectively, p<0.01). The frequency of MES was significantly higher in the symptomatic group than in the asymptomatic group (49/126 vs 2/108, p<0.01). Specifically, the frequency of MES in the symptomatic and asymptomatic groups with mild stenosis, moderate stenosis, severe stenosis and occlusion groups was 4/18 (22.22%) vs 0/30 (0), 13/31 (41.94%) vs 1/28 (3.57%), 30/62 (48.39%) vs 1/39 (2.56%), 2/15 (13.33%) vs 0/11 (0), respectively. Except for the occlusive group, the frequency of MES is correlated with stenosis degree and symptom. Two patients in the asymptomatic group were found positive for MES, and the MES number was 1 for both. During the one-year follow-up, neither of them developed ischemic stroke. In conclusion, MES detected with TCD differs between symptomatic and asymptomatic MCA stenoses. Due to the low frequency, the value of MES as a predictor of subsequent ischemic stroke in patients with asymptomatic MCA stenosis might be limited.

Interhemispheric auditory connectivity: structure and function related to auditory verbal hallucinations

Auditory verbal hallucinations (AVH) are one of the most common and most distressing symptoms of schizophrenia. Despite fundamental research, the underlying neurocognitive and neurobiological mechanisms are still a matter of debate. Previous studies suggested that “hearing voices” is associated with a number of factors including local deficits in the left auditory cortex and a disturbed connectivity of frontal and temporoparietal language-related areas. In addition, it is hypothesized that the interhemispheric pathways connecting right and left auditory cortices might be involved in the pathogenesis of AVH. Findings based on Diffusion-Tensor-Imaging (DTI) measurements revealed a remarkable interindividual variability in size and shape of the interhemispheric auditory pathways. Interestingly, schizophrenia patients suffering from AVH exhibited increased fractional anisotropy (FA) in the interhemispheric fibers than non-hallucinating patients. Thus, higher FA-values indicate an increased severity of AVH. Moreover, a dichotic listening (DL) task showed that the interindividual variability in the interhemispheric auditory pathways was reflected in the behavioral outcome: stronger pathways supported a better information transfer and consequently improved speech perception. This detection indicates a specific structure-function relationship, which seems to be interindividually variable. This review focuses on recent findings concerning the structure-function relationship of the interhemispheric pathways in controls, hallucinating and non-hallucinating schizophrenia patients and concludes that changes in the structural and functional connectivity of auditory areas are involved in the pathophysiology of AVH.

Role of CT angiography for detection of coronary atherosclerosis

As laparoscopic surgery is replacing open surgery, similarly computed tomography angiography is replacing invasive conventional cardiac angiography. In the last century, marvelous efforts in research have improved strategies for cure, diagnosis and prevention of fatal human diseases; however, coronary artery disease, as the most prevalent cause of mortality and morbidity in the world, has remained a great challenge. Due to advancements in technology and research, it has become more simple and robust to diagnose and treat coronary artery disease (CAD) with minimal or no intervention, promising to not only diagnosis at an early stage but potential prevention altogether. While most with obvious CAD can be diagnosed easily and quickly with ECG, those identified as 'low risk' require more extensive testing to diagnose or rule out CAD. For example in emergency departments, low-risk patients with chest pain are diagnosed solely depending on history, ECG and blood testing for biomarkers. This approach has resulted in either delayed or miss-diagnosis of Acute coronary syndrome. To prevent this, many emergency departments now use protocols for low-risk heart patients that include cardiac stress tests and/or CT heart imaging. This review provides an overview of the current literature on the value of Computed tomography angiography and discusses how prognostic information obtained with Computed tomography angiography can be used to further integrate the technique into clinical practice.

Imaging of acute pancreatitis and its complications. Part 1: acute pancreatitis

Acute pancreatitis is an acute inflammatory disease of the pancreas that may also involve surrounding tissues or remote organs. The Atlanta classification of acute pancreatitis was introduced in 1992 and divides patients into mild and severe groups based on clinical and biochemical criteria. Recently, the terminology and classification scheme proposed at the initial Atlanta Symposium have been reviewed and a new consensus statement has been proposed by the Acute Pancreatitis Classification Working Group. Generally, imaging is recommended to confirm the clinical diagnosis, investigate the etiology, and grade the extend and severity of the acute pancreatitis. Ultrasound is the first-line imaging modality in most centers for the confirmation of the diagnosis of acute pancreatitis and the ruling out of other causes of acute abdomen, but it has limitations in the acute clinical setting. Computed tomography not only establishes the diagnosis of acute pancreatitis, but also enables to stage severity of the disease. Magnetic resonance imaging has earned an ever more important role in the diagnosis of acute pancreatitis. It is especially useful for imaging of patients with iodine allergies, characterizing collections and assessment of an abnormal or disconnected pancreatic duct. The purpose of this review article is to present an overview of the acute pancreatitis, clarify confusing terminology, underline the role of ultrasound, computed tomography and magnetic resonance imaging according to the proper clinical context and compare the advantages and limitations of each modality.

Prevalence and risk of cancer of incidental uptake in prostate identified by fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography

OBJECTIVE

The objective was to investigate the prevalence of incidental fluorine-18 fluorodeoxyglucose (FDG) uptake in positron emission tomography/computed tomography.

METHODS

A total of 11,239 male nonprostate disease patients were included retrospectively.

RESULTS

The prevalence of incidental prostate FDG uptake was approximately 1.8%. Among 198 incidental lesions, 100 patients had further examinations; 20 lesions were confirmed to be malignant, while 80 lesions were benign. After logistic regression analysis, age, site, and the maximum standard uptake value were the potent predictors for differentiation of malignant prostate lesions.

CONCLUSION

When focal FDG uptake in the peripheral zone of prostate is detected, especially in elderly men, further clinical evaluation is recommended.

Intra-arterial infusion and chemo-embolization for melanoma liver metastases

This article will review the rationale for hepatic arterial administration of agents to treat melanoma liver metastases, the techniques and practical considerations pertinent to hepatic arterial therapy, the variety of agents that have been used and the reported outcomes. Recent and emerging developments will be highlighted and the potential role of liver-directed therapies in the context of molecular advances and improved systemic therapy will be discussed.

Volume-rendered hemorrhage-responsible arteriogram created by 64 multidetector-row CT during aortography: utility for catheterization in transcatheter arterial embolization for acute arterial bleeding

Aortography for detecting hemorrhage is limited when determining the catheter treatment strategy because the artery responsible for hemorrhage commonly overlaps organs and non-responsible arteries. Selective catheterization of untargeted arteries would result in repeated arteriography, large volumes of contrast medium, and extended time. A volume-rendered hemorrhage-responsible arteriogram created with 64 multidetector-row CT (64MDCT) during aortography (MDCTAo) can be used both for hemorrhage mapping and catheter navigation. The MDCTAo depicted hemorrhage in 61 of 71 cases of suspected acute arterial bleeding treated at our institute in the last 3 years. Complete hemostasis by embolization was achieved in all cases. The hemorrhage-responsible arteriogram was used for navigation during catheterization, thus assisting successful embolization. Hemorrhage was not visualized in the remaining 10 patients, of whom 6 had a pseudoaneurysm in a visceral artery; 1 with urinary bladder bleeding and 1 with chest wall hemorrhage had gaze tamponade; and 1 with urinary bladder hemorrhage and 1 with uterine hemorrhage had spastic arteries. Six patients with pseudoaneurysm underwent preventive embolization and the other 4 patients were managed by watchful observation. MDCTAo has the advantage of depicting the arteries responsible for hemoptysis, whether from the bronchial arteries or other systemic arteries, in a single scan. MDCTAo is particularly useful for identifying the source of acute arterial bleeding in the pancreatic arcade area, which is supplied by both the celiac and superior mesenteric arteries. In a case of pelvic hemorrhage, MDCTAo identified the responsible artery from among numerous overlapping visceral arteries that branched from the internal iliac arteries. In conclusion, a hemorrhage-responsible arteriogram created by 64MDCT immediately before catheterization is useful for deciding the catheter treatment strategy for acute arterial bleeding.

Radiological and practical aspects of body packing

Body packing represents the concealment of illegal substances in a person's body with the aim of smuggling. "Body packers" either swallow drug-filled packets or introduce drug-filled packets into their bodies rectally or vaginally with the purpose of concealing them. The three main smuggled drugs are cocaine, heroin and cannabis products. Body packing represents a serious risk of acute narcotic toxicity from drug exposure, intestinal obstruction owing to pellet impaction and bowel perforation with consequent abdominal sepsis. A suspected body packer is generally admitted to hospital to perform imaging investigations and confirm the presence of drugs in his/her body. Radiological imaging methods are essential to diagnose body packing and to detect potential complications. Increasing sophistication of traffickers and improvements in packaging add to the detection difficulty. Radiologists should be aware of the appearance of drug packets in a range of imaging modalities. This article informs physicians about the challenging aspects of body packing, its background and medicolegal issues, what imaging methods can be used and what criteria are necessary to perform a correct diagnosis.

Factors associated with the impossibility to obtain reliable liver stiffness measurements by means of Acoustic Radiation Force Impulse (ARFI) elastography--analysis of a cohort of 1,031 subjects

INTRODUCTION

Acoustic Radiation Force Impulse (ARFI) elastography is a non-invasive technique for liver fibrosis assessment.

AIM

To assess the feasibility of ARFI elastography in a large cohort of subjects and to identify factors associated with impossibility to obtain reliable liver stiffness (LS) measurements by means of this technique.

METHODS

Our retrospective study included 1031 adult subjects with or without chronic liver disease. In each subject LS was assessed by means of ARFI elastography. Failure of ARFI measurements was defined if no valid measurement was obtained after at least 10 shots and unreliable in the following situations: fewer than 10 valid shots; or median value of 10 valid measurements with a success rate (SR)<60% and/or an interquartile range interval (IQR) ≥ 30%.

RESULTS

Failure of LS measurements by means of ARFI was observed in 4 subjects (0.3%), unreliable measurements in 66 subjects (6.4%), so reliable measurements were obtained in 961 subjects (93.3%). In univariant analysis, the following risk factors were associated with failed and unreliable measurements: age over 58 years (OR=0.49; 95% CI 0.30-0.80, p=0.005), male gender (OR=0.58; 95% CI 0.34-0.94, p=0.04), BMI>27.7 kg/m(2) (OR=0.23, 95% CI 0.13-0.41, p<0.0001). In multivariate analysis all the factors mentioned above were independently associated with the risk of failed and unreliable measurements.

CONCLUSIONS

Reliable LS measurements by means of ARFI elastography were obtained in 93.3% of cases. Older age, higher BMI and male gender were associated with the risk of failed and unreliable measurements, but their influence is limited as compared with Transient Elastography.

Theoretical comparison of the iodine quantification accuracy of two spectral CT technologies

We compare the theoretical limits of iodine quantification for the photon counting multibin and dual energy technologies. Dual energy systems by necessity have to make prior assumptions in order to quantify iodine. We explicitly allow the multibin system to make the same assumptions and also allow them to be wrong. We isolate the effect of technology from imperfections and implementation issues by assuming both technologies to be ideal, i.e., without scattered radiation, unity detection efficiency and perfect energy response functions, and by applying the Cramér-Rao lower bound methodology to assess the quantification accuracy. When priors are wrong the maximum likelihood estimates will be biased and the mean square error of the quantification error is a more appropriate figure of merit. The evaluation assumes identical X-ray spectra for both methodologies and for that reason a sensitivity analysis is performed with regard to the assumed X-ray spectrum. We show that when iodine is quantified over regions of interest larger than 6 cm(2), multibin systems benefit by independent estimation of three basis functions. For smaller regions of interest multibin systems can increase quantification accuracy by making the same prior assumptions as dual energy systems.

Pediatric nephrogenic systemic fibrosis is rarely reported: a RADAR report

BACKGROUND

Nephrogenic systemic fibrosis is a fibrosing disorder associated with exposure to gadolinium-based contrast agents in people with severely compromised renal function.

OBJECTIVE

The purpose of this study was to determine the reported number of cases of nephrogenic systemic fibrosis in children using three distinct publicly available data sources.

MATERIALS AND METHODS

We conducted systematic searches of the U.S. Food and Drug Administration Adverse Event Reporting System (FAERS), the International Center for Nephrogenic Systemic Fibrosis Research (ICNSFR) registry and published literature from January 1997 through September 2012. We contacted authors of individual published cases to obtain follow-up data. Data sets were cross-referenced to eliminate duplicate reporting.

RESULTS

We identified 23 children with nephrogenic systemic fibrosis. Seventeen had documented exposure to gadolinium-based contrast agents. Six children had been reported in both the FAERS and the literature, four in the FAERS and the ICNSFR registry and five in all three data sources.

CONCLUSION

Nephrogenic systemic fibrosis has been rarely reported in children. Although rules related to confidentiality limit the ability to reconcile reports, active pharmaco-vigilance using RADAR (Research on Adverse Drug events And Reports) methodology helped in establishing the number of individual pediatric cases within the three major data sources.

Pancreatic cysts: etiology, diagnosis and management

Pancreatic cysts involve a wide spectrum of pathologies from post-inflammatory cysts to malignant neoplasms. Pancreatic pseudocysts, serous cystadenomas, mucinous cystadenomas, intraductal papillary mucinous neoplasms (IPMNs) and solid pseudopapillary tumors occur most frequently. Differential diagnosis involves the following imaging investigations: transabdominal ultrasonography (TUS), contrast enhanced ultrasonography (CEUS) and endoscopic ultrasonography (EUS), computed tomography (CT), magnetic resonance (MR) and magnetic resonance cholangiopancretography (MRCP), endoscopic retrograde cholangiopancretography (ERCP). The cyst fluid cytology is performed in difficult differential diagnosis between pseudocysts and benign and potentially malignant or malignant tumors. Most frequently, viscosity, amylase, CEA and CA 19-9 levels are determined. Imaging findings should be correlated with cytology. The management depends on the cyst type and size. Small asymptomatic pseudocysts, serous cystadenomas and branchduct IPMNs should be carefully observed, whereas symptomatic large or uncertain serous cystadenomas and cystadenocarcinomas, mucinous cystadenomas and cystadenocarcinomas, main-duct IPMNs and large branch-duct IPMNs with malignant features, serous and mucinous cystadenocarcinomas, and solid pseudopapillary tumors require surgery. Pseudocysts are usually drained. Percutaneous / EUS-guided or surgical cyst drainage can be performed. Complicated and uncertain pseudocysts and cystic tumors need surgical resection. The type of surgery depends on cyst location and size and includes proximal, central, distal, total pancreatectomies and enucleation.

Submucosal tunneling endoscopic resection for small upper gastrointestinal subepithelial tumors originating from the muscularis propria layer

BACKGROUND

This prospective study was designed to evaluate the safety and efficacy of submucosal tunneling endoscopic resection (STER) for small (≤3 cm) upper gastrointestinal (GI) subepithelial tumors (SETs) originating from the muscularis propria (MP) layer.

METHODS

Between August 2011 and February 2013, a total of 85 patients with upper GI SETs originating from the MP layer were treated with STER. The key steps were as follows: (1) locating the tumor by injection of methylene blue or indigo carmine and then creating a submucosal tunnel from 5 cm above the tumor between the submucosal and muscular layers; (2) resecting the tumor by endoscopic resection techniques; (3) closing the mucosal incision site with several clips after the tumor is removed.

RESULTS

Of the 85 SETs, 60 were located in the esophagus, 16 in the cardia, and 9 in the stomach. STER was successfully performed in all cases (success rate: 100 %). The mean tumor size was 19.2 mm. The mean procedure time was 57.2 min. The average hospital stay after the procedure was 5.9 days. Pathological diagnosis of the tumors were leiomyoma (65/85), gastrointestinal stromal tumor (GIST) (19/85), and calcifying fibrous tumor (1/85). During the procedure, eight patients developed pneumothorax, subcutaneous emphysema, and/or pneumoperitoneum. These patients recovered after conservative treatment. The rate of all complications was significantly higher for lesions originating in the deeper MP layer (70 %) than in the superficial MP layer (1.3 %; p < 0.001). The total complication rate for different histological diagnoses was also significantly different (26.3 % for GISTs, 4.6 % for leiomyomas, 0 % for calcifying fibrous tumors, p < 0.05). No residual or recurrent tumors were detected during the follow-up period (median: 8 months).

CONCLUSIONS

Submucosal tunneling endoscopic resection appears to be a feasible, safe, and effective procedure for treatment of small (≤3 cm) upper GI SETs originating from the MP layer.

Longitudinal monitoring with multiple MR techniques in a case of progressive multifocal leukoencephalopathy associated with multiple myeloma

Progressive multifocal leukoencephalopathy (PML) is a demyelinating disease of the brain caused by the JC virus in immunocompromised patients. We report characteristic features of proton MR spectroscopy, 3-dimensional pseudo-continuous arterial spin labeling imaging, and diffusion tensor imaging in a 53-year-old patient with PML. The utility of multi-modal magnetic resonance techniques for longitudinal monitoring was indicated by their reevaluation over time and consideration of their relation to prognosis.

Multimodal voxel-based meta-analysis of structural and functional magnetic resonance imaging studies in those at elevated genetic risk of developing schizophrenia

Computational brain-imaging studies of individuals at familial high risk for psychosis have provided interesting results, but interpreting these findings can be a challenge due to a number of factors. We searched the literature for studies reporting whole brain voxel-based morphometry (VBM) or functional magnetic resonance imaging (fMRI) findings in people at familial high risk for schizophrenia compared with a control group. A voxel-wise meta-analysis with the effect-size version of Signed Differential Mapping (ES-SDM) identified regional abnormalities of functional brain response. Similarly, an ES-SDM meta-analysis was conducted on VBM studies. A multi-modal imaging meta-analysis was used to highlight brain regions with both structural and functional abnormalities. Nineteen studies met the inclusion criteria, in which a total of 815 familial high-risk individuals were compared to 685 controls. Our fMRI results revealed a number of regions of altered activation. VBM findings demonstrated both increases and decreases in grey matter density of relatives in a variety of brain regions. The multimodal analysis revealed relatives had decreased grey matter with hyper-activation in the left inferior frontal gyrus/amygdala, and decreased grey matter with hypo-activation in the thalamus. We found several regions of altered activation or structure in familial high-risk individuals. Reliable fMRI findings in the right posterior superior temporal gyrus further confirm that alteration in this area is a potential marker of risk.

Prevalence and outcomes of symptomatic intracranial large artery stenoses and occlusions in China: the Chinese Intracranial Atherosclerosis (CICAS) Study

BACKGROUND AND PURPOSE

We aimed to establish the prevalence, characteristics, and outcomes of intracranial atherosclerosis (ICAS) in China by a large, prospective, multicenter study.

METHODS

We evaluated 2864 consecutive patients who experienced an acute cerebral ischemia<7 days after symptom onset in 22 Chinese hospitals. All patients underwent magnetic resonance angiography, with measurement of diameter of the main intracranial arteries. ICAS was defined as ≥50% diameter reduction on magnetic resonance angiography.

RESULTS

The prevalence of ICAS was 46.6% (1335 patients, including 261 patients with coexisting extracranial carotid stenosis). Patients with ICAS had more severe stroke at admission and stayed longer in hospitals compared with those without intracranial stenosis (median National Institutes of Health Stroke Scale score, 3 versus 5; median length of stay, 14 versus 16 days; both P<0.0001). After 12 months, recurrent stroke occurred in 3.27% of patients with no stenosis, in 3.82% for those with 50% to 69% stenosis, in 5.16% for those with 70% to 99% stenosis, and in 7.27% for those with total occlusion. Cox proportional hazards regression analyses showed that the degree of arterial stenosis, age, family history of stroke, history of cerebral ischemia or heart disease, complete circle of Willis, and National Institutes of Health Stroke Scale score at admission were independent predictors for recurrent stroke at 1 year. The highest rate of recurrence was observed in patients with occlusion with the presence of ≥3 additional risk factors.

CONCLUSIONS

ICAS is the most common vascular lesion in patients with cerebrovascular disease in China. Recurrent stroke rate in our study was lower compared with those of previous clinical trials but remains unacceptably high in a subgroup of patients with severe stenosis.

Management of hepatocellular carcinoma: The role of contrast-enhanced ultrasound

Hepatocellular carcinoma (HCC) is the sixth most common neoplasm and the third cause of cancer death worldwide. Contrast enhanced ultrasound (CEUS) has been applied for more than ten years and plays increasingly important roles in the management of HCC. On the basis of the Guideline and Good Clinical Practice Recommendations for CEUS in the liver-update 2012 and related literature about the management of HCC, we summarize the main roles and applications of CEUS in the management of HCC, including HCC surveillance, diagnosis, CEUS-guided treatment, treatment response evaluation and follow-up. The diagnostic algorithm for HCC is also suggested. Meanwhile, the comparisons between CEUS and contrast enhanced computed tomography/magnetic resonance imaging (CECT/CEMRI) in these areas are made. Although CEUS is subject to the same limitation as ordinary US and is inferior to CECT/CEMRI in some aspects, CEUS has proved to be of great value in the management of HCC with inherent advantages, such as sufficient high safety profile making it suitable for patients with renal failure or allergic to iodine, absence of radiation, easy reproducibility and high temporal resolution. The tremendous application of CEUS to the diagnosis and treatment of HCC provides more opportunities for patients with HCC diagnosed at different stages.

Therapeutic efficacy comparison of radiofrequency ablation in hepatocellular carcinoma and metastatic liver cancer

The aim of this study was to evaluate the effect of radiofrequency ablation (RFA) on malignant hepatic tumors and compare its therapeutic efficacy in hepatocellular carcinoma (HCC) and metastatic liver cancer (MLC). A total of 56 patients with malignant hepatic tumors (34 patients with HCC and 22 patients with MLC) underwent RFA treatment. Two weeks following the RFA treatment, contrast-enhanced abdominal computed tomography scans were used to investigate whether the ablation of the tumors was complete. The patients were followed up for a period ranging from 1 to 93 months, to compare recurrence rates, distant recurrence rates and survival rates. The HCC group exhibited an initial complete ablation rate of 94.1% compared with 95.4% for the MLC group; the difference in ablation rates was not identified to be statistically significant. The recurrence and distant recurrence rates were 14.7% and 11.8%, respectively, for the HCC group and 9.1% and 36.4%, respectively, for the MLC group. The 1-, 3- and 5-year survival rates of the patients with HCC were 86.2, 71.4 and 60.0%, respectively, whereas those for the patients with MLC were 73.9%, 45.4% and 37.5%, respectively. The survival rates of the two groups were identified to be significantly different (P=0.002). RFA treatment was therefore shown to be effective in treating small (<5 cm) malignancies, which is clinically significant.

Case report: maximum-intensity projection and minimum-intensity projection of computed tomography are helpful in the diagnosis of Budd-Chiari syndrome in complicated liver cirrhosis

BACKGROUND

Early detection of Budd-Chiari syndrome (BCS) to give the appropriate therapy in time is crucial. Angiography remains the golden standard to diagnose BCS. However, to establish the diagnosis of BCS in complicated cirrhotic patients remains a challenge. We used maximum intensity projection (Max IP) and minimum intensity projection (Min IP) from computed tomographic (CT) images to detect this syndrome in such a patient.

CASE REPORT

A 55-year-old man with a history of chronic hepatitis B infection and alcoholism had undergone previously a left lateral segmentectomy for hepatic epitheloid angiomyolipoma (4.6 × 3.5 × 3.3 cm) with a concomitant splenectomy. Liver decompensation with intractable ascites and jaundice occurred 4 months later. The reformed images of the venous phase of enhanced CT images with Max IP and Min IP showed middle hepatic vein thrombosis. He then underwent a living-related donor liver transplantation with a right liver graft from his daughter. Intraoperatively, we noted thrombosis of his middle hepatic vein protruding into inferior vena cava. The postoperative course was unevenful. Microscopic findings revealed micronodular cirrhosis with mixed inflammation in the portal areas. Some liver lobules exhibited congestion and sinusoidal dilation compatible with venous occlusion clinically.

CONCLUSIONS

We recommend Max IP and Min IP of CT images as simple and effective techniques to establish the diagnosis of BCS, especially in complicated cirrhotic patients, thereby avoiding invasive interventional procedures.

Pineal gland volume in primary insomnia and healthy controls: a magnetic resonance imaging study

Little is known about the relation between pineal volume and insomnia. Melatonin promotes sleep processes and, administered as a drug, it is suitable to improve primary and secondary sleep disorders in humans. Recent magnetic resonance imaging studies suggest that human plasma and saliva melatonin levels are partially determined by the pineal gland volume. This study compares the pineal volume in a group of patients with primary insomnia to a group of healthy people without sleep disturbance. Pineal gland volume (PGV) was measured on the basis of high-resolution 3 Tesla MRI (T1-magnetization prepared rapid gradient echo) in 23 patients and 27 controls, matched for age, gender and educational status. Volume measurements were performed conventionally by manual delineation of the pineal borders in multi-planar reconstructed images. Pineal gland volume was significantly smaller (P < 0.001) in patients (48.9 ± 26.6 mm(3) ) than in controls (79 ± 30.2 mm(3) ). In patients PGV correlated negatively with age (r = -0.532; P = 0.026). Adjusting for the effect of age, PGV and rapid eye movement (REM) latency showed a significant positive correlation (rS  = 0.711, P < 0.001) in patients. Pineal volume appears to be reduced in patients with primary insomnia compared to healthy controls. Further studies are needed to clarify whether low pineal volume is the basis or the consequence of functional sleep changes to elucidate the molecular pathology for the pineal volume loss in primary insomnia.

Usefulness of 3T diffusion-weighted MRI for discrimination of reactive and metastatic cervical lymph nodes in patients with oral squamous cell carcinoma: a pilot study

OBJECTIVES

To study the diagnostic accuracy of 3T diffusion-weighted MRI (DW-MRI) for the discrimination of reactive and metastatic cervical lymph nodes in patients with oral squamous cell carcinoma.

METHODS

DW T1 and T2 weighted MRI was performed in 25 patients with biopsy-proved primary oral squamous cell carcinoma. The mean apparent diffusion coefficient (ADC) values of 30 histopathologically proved reactive lymph nodes and 21 histopathologically proved metastatic lymph nodes were compared using an unpaired t-test. A cut-off ADC value with optimal diagnostic sensitivity, specificity and area under the curve in discrimination of the two groups was determined using a receiver operating characteristic curve analysis.

RESULTS

The mean ADC values of reactive lymph node and metastatic lymph node groups were (1.037 ± 0.149) × 10(-3) and (0.702 ± 0.197) × 10(-3) mm(2) s(-1), respectively. A statistically significant difference in ADC values of the two groups was certified (p < 0.0001). An optimal ADC threshold value of 0.887 × 10(-3) mm(2) s(-1) was suggested as the cut-off point, which resulted in 93.33% sensitivity, 80.95% specificity, 88.20% accuracy and area under curve of 0.887.

CONCLUSIONS

Our preliminary study indicates that the addition of 3T DW-MRI may be useful for discriminating between reactive lymph nodes and metastatic lymph nodes in patients with oral squamous cell carcinoma. However, larger studies are still required to validate our results and to standardize this imaging technique for daily clinical practice.

Diffuse large B-cell lymphoma of the mandible with periosteal reaction: a case report

This report describes a rare case of a 63-year-old man with a lymphoma in the right mandibular ramus with periosteal reaction. Computed tomography (CT) images showed a soft tissue density (28 × 48 × 32 mm) around the right mandibular foramen. Bone-mode CT images showed diffuse bone destruction of the right mandibular ramus. Moreover, a periosteal reaction was seen on the lingual cortical bone of the right mandibular ramus. Histopathologic examination found a diffuse large B-cell lymphoma.

Computed tomography-based preoperative vascular imaging in autologous breast reconstruction: A Canadian perspective

There appears to be increased use of computed tomography angiography (CTA) in the preoperative planning of autologous perforator flap breast reconstruction. Despite the advantages of providing superior anatomical detail, concerns regarding cost and radiation exposure of this technique remain. In the current study, a paper-based survey was distributed to 44 plastic surgeons with a special interest in breast reconstruction at 19 different centres across Canada to collect their perspectives and practice characteristics with respect to the use of CTA as a preoperative imaging modality in breast reconstruction. The response rate of the survey was 75%. The majority of respondents commonly use perforator flap breast reconstruction and CTA in their breast reconstruction practice. Surgeons identified particular benefits of CTA in patients who had previously undergone abdominal surgery. However, more than one-half of the overall cohort was concerned about radiation exposure associated with CTA. A review of the literature suggests that it may be worthwhile to reduce the unnecessary risks of additional radiation exposure to the breast cancer population. A prospective study may help to better define the group of patients in whom CTA will provide optimal benefits in terms of reducing perioperative microvascular morbidity.

Evolving role of MRI in Crohn's disease

MR enterography is playing an evolving role in the evaluation of small bowel Crohn's disease (CD). Standard MR enterography includes a combination of rapidly acquired T2 sequence, balanced steady-state acquisition, and contrast enhanced T1-weighted gradient echo sequence. The diagnostic performance of these sequences has been shown to be comparable, and in some respects superior, to other small bowel imaging modalities. The findings of CD on MR enterography have been well described in the literature. New and emerging techniques such as diffusion-weighted imaging (DWI), dynamic contrast enhanced MRI (DCE-MRI), cinematography, and magnetization transfer, may lead to improved accuracy in characterizing the disease. These advanced techniques can provide quantitative parameters that may prove to be useful in assessing disease activity, severity, and response to treatment. In the future, MR enterography may play an increasing role in management decisions for patients with small bowel CD; however, larger studies are needed to validate these emerging MRI parameters as imaging biomarkers.

Initial imaging analysis of Budd-Chiari syndrome in Henan province of China: most cases have combined inferior vena cava and hepatic veins involvement

AIM

To evaluate the type of venous involvement in Chinese Budd-Chiari syndrome (BCS) patients and the relative diagnostic accuracy of the different imaging modalities.

METHODS

Using digital subtraction angiography (DSA) as a reference standard, color Doppler ultrasound (CDUS), computed tomography angiography (CTA), and magnetic resonance angiography (MRA) were performed on 338 patients with BCS. We analyzed the course of the main and any accessory hepatic veins (HVs) and the inferior vena cava (IVC) to assess the etiology of obstructed segments and diagnostic accuracy of CDUS, CTA and MRA.

RESULTS

Among the 338 cases, there were 8 cases (2.4%) of isolated IVC membranous obstruction, 45 cases (13.3%) of isolated HV occlusion, and 285 cases (84.3%) with both IVC membranous obstruction and HV occlusion. Comparing with DSA, CDUS, CTA had a diagnostic accuracy of 89.3% and 80.2% in detecting BCS, and 83.4% of cases correctly correlated by MRA.

CONCLUSION

In Henan Province, most patients with BCS have complex lesions combining IVC and HV involvement. The combination of CDUS and CTA or MRI is useful for diagnosis of BCS and guiding therapy.

Magnetic resonance imaging of meningiomas: a pictorial review

Meningiomas are the most common non-glial tumour of the central nervous system (CNS). There are a number of characteristic imaging features of meningiomas on magnetic resonance imaging (MRI) that allow an accurate diagnosis, however there are a number of atypical features that may be diagnostically challenging. Furthermore, a number of other neoplastic and non-neoplastic conditions may mimic meningiomas. This pictorial review discusses the typical and atypical MRI features of meningiomas and their mimics.

TEACHING POINTS

There are several characteristic features of meningiomas on MRI that allow an accurate diagnosis Some meningiomas may display atypical imaging characteristics that may be diagnostically challenging Routine MRI sequences do not reliably distinguish between benign and malignant meningiomas Spectroscopy and diffusion tensor imaging may be useful in the diagnosis of malignant meningiomas A number of conditions may mimic meningiomas; however, they may have additional differentiating features.

Accuracy of high-resolution MRI with lumen distention in rectal cancer staging and circumferential margin involvement prediction

Objective

To evaluate the accuracy of magnetic resonance imaging (MRI) with lumen distention for rectal cancer staging and circumferential resection margin (CRM) involvement prediction.

Materials and Methods

Seventy-three patients with primary rectal cancer underwent high-resolution MRI with a phased-array coil performed using 60-80 mL room air rectal distention, 1-3 weeks before surgery. MRI results were compared to postoperative histopathological findings. The overall MRI T staging accuracy was calculated. CRM involvement prediction and the N staging, the accuracy, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were assessed for each T stage. The agreement between MRI and histological results was assessed using weighted-kappa statistics.

Results

The overall MRI accuracy for T staging was 93.6% (k = 0.85). The accuracy, sensitivity, specificity, PPV and NPV for each T stage were as follows: 91.8%, 86.2%, 95.5%, 92.6% and 91.3% for the group ≤ T2; 90.4%, 94.6%, 86.1%, 87.5% and 94% for T3; 98,6%, 85.7%, 100%, 100% and 98.5% for T4, respectively. The predictive CRM accuracy was 94.5% (k = 0.86); the sensitivity, specificity, PPV and NPV were 89.5%, 96.3%, 89.5%, and 96.3% respectively. The N staging accuracy was 68.49% (k = 0.4).

Conclusion

MRI performed with rectal lumen distention has proved to be an effective technique both for rectal cancer staging and involved CRM predicting.

Alveolar echinococcosis of the liver: diffusion-weighted MRI findings and potential role in lesion characterisation

PURPOSE

To report the diffusion-weighted MRI findings in alveolar echinococcosis (AE) of the liver and evaluate the potential role of apparent diffusion coefficients (ADCs) in the characterisation of lesions.

MATERIALS AND METHODS

We retrospectively included 22 patients with 63 AE liver lesions (≥1 cm), examined with 3-T liver MRI, including a free-breathing diffusion-weighted single-shot echo-planar imaging sequence (b-values=50, 300 and 600 s/mm(2)). Two radiologists jointly assessed the following lesion features: size, location, presence of cystic and/or solid components (according to Kodama's classification system), relative contrast enhancement, and calcifications (on CT). The ADC(total), ADC(min) and ADC(max) were measured in each lesion and the surrounding liver parenchyma.

RESULTS

Three type 1, 19 type 2, 17 type 3, three type 4 and 21 type 5 lesions were identified. The mean (±SD) ADC(total), ADC(min) and ADC(max) for all lesions were 1.73 ± 0.50, 0.76 ± 0.38 and 2.63 ± 0.76 × 10(-3)mm(2)/s, respectively. The mean ADC(total) for type 1, type 2, type 3, type 4 and type 5 lesions were 1.97 ± 1.01, 1.76 ± 0.53, 1.73 ± 0.41, 1.15 ± 0.42 and 1.76 ± 0.44 × 10(-3)mm(2)/s, respectively. No significant differences were found between the five lesion types, except for type 4 (p=0.0363). There was a significant correlation between the presence of a solid component and low ADCmin (r=0.39, p=0.0016), whereas an inverse correlation was found between the relative contrast enhancement and ADCtotal (r=-0.34, p=0.0072).

CONCLUSION

The ADCs of AE lesions are relatively low compared to other cystic liver lesions, which may help in the differential diagnosis. Although ADCs are of little use to distinguish between the five lesion types, their low value reflects the underlying solid component.

Involvement of both cervical lymph nodes and retropharyngeal lymph nodes has prognostic value for N1 patients with nasopharyngeal carcinoma

Background

The N1 definition of 2010 UICC/AJCC staging system for nasopharyngeal carcinoma (NPC) covers quite a large range of nodal pattern. The objective of this research is to investigate prognostic value of lymph nodes related factors including involvement of both cervical lymph nodes (CLNs) and retropharyngeal lymph nodes (RLNs) or not, size and number of cervical lymph nodes (CLNs) in N1 patients with NPC.

Methods

142 newly diagnosed non-metastatic N1 patients with NPC, staged according to the 2010 AJCC staging system for NPC were retrospectively enrolled. All patients had undergone contrast-enhanced magnetic resonance imaging (MRI), and received radiotherapy, with or without chemotherapy as their primary treatment.

Results

The median follow-up was 48 months. The 5-year local recurrence-free survival (LFS), nodal recurrence-free survival (NFS), local-regional recurrence-free survival (LRFS), distant metastasis-free survival (DMFS), progression-free survival (PFS), and overall survival (OS) of the whole group were 82.3%, 83.0%, 81.0%, 82.1%, 75.3% and 89.8%, respectively. In univariate analysis, patients with both CLNs and RLNs involvement showed a significant lower DMFS, PFS and LRFS than the rest patients (p = 0.004 p = 0.003 and p = 0.034, respectively). Neither size nor number of CLNs affected the survival. In multivariate analysis, involvement of both CLNs and RLNs was an independent prognostic factor for DMFS and PFS (p = 0.019, p = 0.019), but there was no enough evidence confirming its prognostic value for LRFS (p = 0.051).

Conclusions

For N1 patients with NPC, involvement of both RLNs and CLNs may be a potentially prognostic factor for distant metastasis and disease progression. The N stage for N1 patients with involvement of both cervical lymph nodes and retropharyngeal lymph nodes might need to be deliberated.

Evolution of the ablation region after magnetic resonance-guided high-intensity focused ultrasound ablation in a Vx2 tumor model

OBJECTIVES

Volumetric magnetic resonance (MR)-guided high-intensity focused ultrasound (HIFU) is a completely noninvasive image-guided thermal ablation technique. Recently, there has been growing interest in the use of MR-HIFU for noninvasive ablation of malignant tumors. Of particular interest for noninvasive ablation of malignant tumors is reliable treatment monitoring and evaluation of response. At this point, there is limited evidence on the evolution of the ablation region after MR-HIFU treatment. The purpose of the present study was to comprehensively characterize the evolution of the ablation region after volumetric MR-HIFU ablation in a Vx2 tumor model using MR imaging, MR temperature data, and histological data.

MATERIALS AND METHODS

Vx2 tumors in the hind limb muscle of New Zealand White rabbits (n = 30) were ablated using a clinical MR-HIFU system. Twenty-four animals were available for analyses. Magnetic resonance imaging was performed before and immediately after ablation; MR temperature mapping was performed during the ablation. The animals were distributed over 7 groups with different follow-up lengths. Depending on the group, animals were reimaged and then killed on day 0, 1, 3, 7, 14, 21, or 28 after ablation. For all time points, the size of nonperfused areas (NPAs) on contrast-enhanced T1-weighted (CE-T1-w) images was compared with lethal thermal dose areas (ie, the tissue area that received a thermal dose of 240 equivalent minutes or greater [EM] at 43°C) and with the necrotic tissue areas on histology sections.

RESULTS

The NPA on CE-T1-w imaging showed an increase in median size from 266 ± 148 to 392 ± 178 mm(2) during the first day and to 343 ± 170 mm(2) on day 3, followed by a gradual decrease to 113 ± 103 mm(2) on day 28. Immediately after ablation, the NPA was 1.6 ± 1.4 times larger than the area that received a thermal dose of 240 EM or greater in all animals. The median size of the necrotic area on histology was 1.7 ± 0.4 times larger than the NPA immediately after ablation. After 7 days, the size of the NPA was in agreement with the necrotic tissue area on histology (ratio, 1.0 ± 0.2).

CONCLUSIONS

During the first 3 days after MR-HIFU ablation, the ablation region increases in size, after which it gradually decreases in size. The NPA on CE-T1-w imaging underestimates the extent of tissue necrosis on histology in the initial few days, but after 1 week, the NPA is reliable in delineating the necrotic tissue area. The 240-EM thermal dose limit underestimates the necrotic tissue area immediately after MR-HIFU ablation. Reliable treatment evaluation techniques are particularly important for noninvasive, image-guided tumor ablation. Our results indicate that CE-T1-w imaging is reliable for MR-HIFU treatment evaluation after 1 week.

Endovascular repair of direct carotid-cavernous fistula in Ehlers-Danlos type IV

Ehlers-Danlos syndrome (EDS) type IV is a collagen vascular disease with an autosomal dominant inheritance caused by COL3A1 mutation. Patients with EDS type IV can present with organ rupture, spontaneous arterial dissections and ruptured aneurysms. Because of their propensity to form arterial dissections, aneurysms and rupture, they can develop carotid-cavernous fistula (CCF) after minor trauma or spontaneously. In EDS, it has been reported that even conventional catheter diagnostic angiography may result in large artery dissections and vessel rupture. In addition, the treatment of CCF in EDS type IV can result in up to 59% mortality after initial treatment, of which 23% is attributed to direct complications of treatment. We present the case of a patient with EDS type IV who previously had spontaneous dissection and multiple pseudoaneurysms of both the iliac and femoral arteries and the distal abdominal aorta. Several years later the patient developed a direct type A CCF which was successfully treated with endovascular embolization using a transvenous approach with detachable coils. The literature pertaining to CCF in EDS type IV and its treatment is reviewed.

Primary and secondary hepatic lymphomas diagnosed by image-guided fine-needle aspiration: a retrospective study of clinical and cytomorphologic findings

OBJECTIVES

To explore the diagnosis of hematolymphoid malignancies of the liver (hepatic lymphoma [HeL]) by image-guided fine-needle aspiration (FNA), which can often be difficult due to a low index of suspicion and nonspecific patient presentations, especially in the rare cases where the liver is the only site of disease (primary HeL [PHeL]). Understanding the clinical setting in which such lesions arise, as well as the cytomorphologic findings, may assist cytopathologists in making an accurate diagnosis and triaging samples for ancillary studies.

METHODS

In this retrospective study of 32 patients with HeL, the largest such study to our knowledge, we review the clinical and diagnostic features of HeL.

RESULTS

HeL and especially PHeL most commonly show a diffuse large B-cell lymphoma phenotype and have a poor prognosis (median survival of seven months). PHeL is strongly associated with human immunodeficiency virus infection (12/16 patients).

CONCLUSIONS

Image-guided FNA with immediate evaluation is a reliable means to obtain diagnostic material and triage for ancillary tests.

Contrast-enhanced ultrasonography findings using a perflubutane-based contrast agent in patients with early hepatocellular carcinoma

OBJECTIVE

We evaluated the contrast-enhanced ultrasonography (US) imaging features of early hepatocellular carcinomas (HCCs) and compared these findings with those obtained using contrast-enhanced computed tomography (CT).

SUBJECTS AND METHODS

Forty-three patients with 52 early HCCs with a mean maximal diameter of 15.6mm were enrolled in this retrospective study. After confirming the location of the target lesion using fusion imaging combining conventional US and hepatobiliary phase of contrast-enhanced magnetic resonance (MR) imaging with gadolinium ethoxybenzyl diethylenetriaminepentaacetic acid, we evaluated findings of contrast-enhanced US using a perflubutane-based contrast agent. The contrast-enhanced US detection rates for hyper-vascularity in early HCCs were compared with those obtained for contrast-enhanced CT.

RESULTS

Transient hypo-vascularity subsequent to iso-vascularity during arterial phase and iso-vascularity during portal and post-vascular phases were the predominant contrast-enhanced US findings seen for 25 (48.1%) of the 52 early HCCs. Nine (17.3%) showed iso-vascularity during all three phases, while 1 (1.9%) showed hypo-vascularity during all three phases. The remaining 17 (32.7%) showed partial or whole hyper-vascularity during arterial phase, iso-vascularity during portal phase, and iso- or hypo-vascularity during post-vascular phase. The detection rate for the hyper-vascularity of early HCCs using contrast-enhanced US (32.7%, 17/52) was significantly higher than that obtained using contrast-enhanced CT (21.2%, 11/52) (P<0.05 by McNemar test).

CONCLUSION

Hypo-vascularity, iso-vascularity, and hyper-vascularity were observed during the arterial phase of contrast-enhanced US in 50.0%, 17.3%, and 32.7% of the early HCCs, respectively. Contrast-enhanced US was more sensitive than contrast-enhanced CT for the detection of hyper-vascularity in early HCCs. Of note, early HCCs might not exhibit the early arterial enhancement that is generally considered to be a typical finding for HCCs.

Terahertz pulsed spectroscopy of paraffin-embedded brain glioma

The refractive indices, absorption coefficients, and complex dielectric constants of paraffin-embedded brain glioma and normal brain tissues have been measured by a terahertz time-domain spectroscopy (THz-TDS) system in the 0.2- to 2.0-THz range. The spectral differences between gliomas and normal brain tissues were obtained. Compared with normal brain tissue, our results indicate that paraffin-embedded brain gliomas have a higher refractive index, absorption coefficient, and dielectric constant. Based on these results, the best THz frequencies for different methods of paraffin-embedded brain glioma imaging, such as intensity imaging, coherent imaging with continuum THz sources, and THz pulsed imaging with short-pulsed THz sources, are analyzed.

Chondromyxoid fibroma of the mandible: Case report and review of the literature

INTRODUCTION

Chondromyxofibroma (CMF) is exceedingly rare, accounting for 0.5% of the 10,065 bone tumors categorized by Unni and Inwards and 1.6% of their catalog of benign bone tumors. Only 2 of the 50 chondromyxoid fibromas included in their study occurred in the skull. Chondromyxoid fibroma of the maxillofacial region is typically seen in patients in the 2nd-3rd decade of life with slight female predominance. It is more commonly seen in the maxilla and is unusual in the sphenoid and ethmoid sinuses. The tumor is composed of hypocellular chondroid or myxochondroid tissue with multinucleated giant cells.

CASE REPORT

A 30 year old Nigerian house wife was seen at the Oral and Maxillofacial clinic of the Dental and Maxillofacial Department of the Federal Medical Centre Lokoja with a 4 year history of Rt mandibular swelling which was initially slow growing and painless and difficulty in eating. The whole lesion was removed and result confirmed the previous biopsy of chondromyxofbroma of the jaw.

CONCLUSION

Patients with CMF need close monitoring due to high rate of recurrence with cases of malignant transformation at rate of 1-2%, and this seems to have occurred following irradiation.