Diffusion-weighted magnetic resonance imaging in the prediction and assessment of chemotherapy outcome in liver metastases

Purpose

This study assessed the capability of magnetic resonance (MR) diffusion-weighted imaging (DwI) with measurement of apparent diffusion coefficient (ADC) in both predicting and evaluating the response to chemotherapy (CHT) of liver metastases by itself and along with preliminary dimensional assessment.

Methods and materials

Patients affected by liver metastases from cancers of the digestive tract and breast were prospectively enrolled and underwent computed tomography and MR-DwI before CHT (time 0) and 20–25 days after the beginning of the second cycle (time 3). Moreover, MR-DwI was performed 10–15 (time 1) and 20–25 days (time 2) after the beginning of the first cycle. Maximum diameter and mean ADC value (×10^?3 mm²/s) of metastases were evaluated. Lesions were classified as progressive disease (PD), stable disease (SD) or partial response (PR) according to dimensional changes between time 0 and time 3, following RECIST 1.1 indications. Clinically, PD lesions were defined as nonresponding (NR), and SD and PR lesions as responding (R). Analysis of variance and ROC analyses were performed (significance at p < 0.05).

Results

Eighty-six metastases (33 patients) were classified as follows: 15 PD, 39 SD and 32 PR without significant differences in mean ADC values among the groups before CHT and at all corresponding times. The mean ADC values of SD and PR groups at times 1 (respectively 1.66 ± 0.36 and 1.59 ± 0.23), 2 (1.72 ± 0.42 and 1.68 ± 0.37) and 3 (1.86 ± 0.44 and 1.73 ± 0.39) were significantly higher than the corresponding values at time 0 (1.50 ± 0.30 and 1.39 ± 0.33). An accurate cutoff value of ADC increase or diameter decrease for the early identification of R or NR lesions was not found.

Conclusion

The pretreatment ADC value of a liver metastasis does not seem useful in predicting the CHT outcome. A trend towards early ADC increase, alone or occurring with dimensional decrease, may be a good indicator of a responding lesion.     

CT enterography as a powerful tool for the evaluation of inflammatory activity in Crohn’s disease: relationship of CT findings with CDAI and acute-phase reactants

Purpose

Few studies have correlated computed tomography enterography (CTE) findings with Crohn’s disease (CD) clinical and biochemical activity. The aim of this study was to evaluate correlations between CTE findings with CD activity.

Materials and methods

The CTE datasets from 62 patients were retrospectively reviewed for different parameters: bowel wall thickening and hyperenhancement, mesenteric alterations, abdominal free fluid and complications related to the disease (fistulas, strictures, abscesses). Activity was assessed using the Crohn’s Disease Activity Index (CDAI) and some biochemical markers (C-reactive protein, erythrocyte sedimentation rate, alpha 2-globulins, fibrinogen, platelets, haemoglobin). Correlations between CTE parameters, clinical activity score and laboratory parameters were assessed by logistic regression.

Results

CDAI was significantly correlated with increased fat density (p = 0.03) and intestinal strictures (p = 0.04). Platelet counts were elevated in patients with enlarged mesenteric lymph nodes (p = 0.009) and the comb sign (p = 0.05). Serum alpha 2-globulins were higher in the presence of the comb sign (p = 0.03).

Conclusion

The CTE finding of perienteric inflammation (increased fat density) and vascular engorgement of the vasa recta in CD patients suggest that the disease is clinically active and that these patients may require more aggressive treatment than patients without these findings.     

Contrast-enhanced MR cholangiography (MRCP) with GD-EOB-DTPA in evaluating biliary complications after surgery

Purpose

We assessed the usefulness of contrast-enhanced magnetic resonance cholangiography (CE-MRC) with liver-specific contrast agent in evaluating the biliary tree after hepatic surgery.

Materials and methods

A total of 142 patients with suspected biliary complications after liver surgery underwent hepatobiliary MR before and after administration of gadolinium ethoxy benzylic diethylenetriamine pentaacetic acid (Gd-EOB-DTPA). Unenhanced MR cholangiopancreatography (MRCP) and postcontrast MRC were obtained in all patients. Blinded image evaluation and semiquantitative analysis comparing MRCP and CE-MRC were performed by two experienced radiologists.

Results

In all cases, optimal postcontrast visualisation of the biliary tract was obtained. In 22 patients, a postsurgical biliary complication was confirmed. MRCP detected 64% of lesions, but in 36% of cases, an alteration was only suspected but not clearly defined. CE-MRC allowed definite diagnosis in 100% of cases.

Conclusions

Hepatobiliary-specific contrast agents allow for accurate and extensive study of biliary tract alterations, especially in assessing postsurgical complications.     

Pulse inversion ultrasonography with ultrasonography contrast media (levovist) in the evaluation of hepatic metastasis

PURPOSE: To evaluate if Pulse Inversion Harmonic Imaging with contrast agent injection (Levovist) is able to determine an increase of echogenicity in normal hepatic parenchyma, and to compare its capability to detect metastatic focal lesions with that of standard US and spiral CT. To define and standardize the technical and methodological aspects of this new technique. MATERIAL AND METHODS: A selected group of 72 patients (42 males and 30 females) with clinical and instrumental suspect of hepatic metastatic lesions was included in the prospective study. Each patient was examined by conventional ultrasound (US), Pulse Inversion Harmonic Imaging (PI) and spiral-CT (spCT). US examination was performed using an HDI 5000 (ATL, Bothell, USA) equipped with a broadband probe (5.0-2.0 MHz). 2.5 g Levovist (Schering AG-Berlin) was administered intravenously, at concentration of 300 mg/ml and a flow rate of 7 ml/min. Video clips obtained with the acquired images before and after contrast medium administration were transferred to a magnet optic disk unit. Examinations were evaluated by an experienced radiologist blindly on a workstation that allowed a qualitative-quantitative analysis. SpCT images were evaluated separately by another experienced radiologist. US images were evaluated qualitatively (number of lesions, site of lesion, diameter of the smallest lesion detectable) and quantitatively (increase in parenchymal echogenicity 20", 40", 60" and 5' after the injection of contrast agent). RESULTS: In all cases examined, the echogenicity of normal hepatic parenchyma increased after contrast agent administration, reaching a peak of about 250% (1DS) at 60 s and a decreasing gradually in 5 minutes. Conventional US detected 195 focal lesions, CT 231, and US with pulse inversion technique and contrast agent (US-PI) 287. Mean differences among the number of lesions detected by the different techniques per each patient were also calculated. Wilcoxon Signed Rank Test showed a statistically significant difference between US-PI and US (p < .0001), CT and US (p = .0052) and US-PI and CT (p = .0121). US-PI detected the smallest lesions, which went undetected by the CT and conventional US examinations. DISCUSSION AND CONCLUSIONS: In 10 cases (14.3%) contrast enhanced US-PI demonstrated the presence of a number of lesions greater than 5 (diffuse metastatization and inoperability) in comparison to that detected by spCT). The greater echogenicity of normal hepatic parenchyma using pulse inversion technique after Levovist infusion allowed to better demonstrate hepatic metastases. This technique showed a higher identification rate of small lesions in comparison to basal examination and to spiral CT. Contrast enhanced US-PI demonstrated a remarkable increase in echogenicity of hepatic parenchyma in portal phase. The technique significantly improves the detection of focal lesions allowing visualization of smaller lesions compared to CT and US. These results indicate that the technique could be used in the staging of liver metastasis. However, large multicentric trials are required to validate US-PI and better define its role in the work-up of patients with neoplastic disorder.     

MR imaging of rheumatoid hand lesions: comparison with conventional radiology in 31 patients.

The purpose of this study was to evaluate the diagnostic accuracy of magnetic resonance imaging (MRI) in rheumatoid arthritis (RA) by comparing MRI with conventional radiology (CR) findings and by correlating these findings with the clinical and serological profile of the disease. The hands of 31 patients (24 females, 7 males) affected by classical RA were studied using a Magnetom 1.0 T tomograph. Coronal, axial, and/or sagittal SE T1 and GE (FLASH 2D FL: 70 degrees-15 degrees) images were obtained in all patients. Moreover, in 7 patients the MRI study was performed after i.v. injection of Gd DTPA contrast medium (0.2 mM/kg). Ten healthy volunteers were also studied as controls. In all patients a conventional radiological study was performed as well as a clinical and serological investigation. Two blinded observers evaluated the MRI and CR findings and checked 15 elementary pathological lesions, assigning an MRI and a CR score to each patient. MRI provided higher accuracy than CR in detecting rheumatoid soft tissue changes and minimal skeletal lesions, while the opposite was true for severe skeletal lesions. No correlations emerged between the MRI/CR findings and clinical and serological data. This study suggests that MRI and CR are complementary techniques in the evaluation of the anatomical changes in RA.     

Nodular pulmonary lesions. Evaluation of the significance of the radiographic semeiotics correlated with the results of transbronchial fiberscopic pulmonary biopsy and transparietal needle aspiration

The results obtained in 148 patients affected by nodular lung lesions have been evaluated. Transbronchial pulmonary biopsies (TBPB) and/or transthoracic fine needle biopsies (NB) have been performed. Diagnostic yield of the performed procedures was 61.5% for TBPB and 91.5% for NB. Radiographic findings and their incidence rates in benign and malignant nodular lung lesions have been considered. Accuracy rate of radiographic features, evaluated by discriminant analysis, was 77.4%. Radiographic appearance has been more related to NB (87.6%) than to TBPB (72.5%).     

Radiological study of the thorax. Evaluation of efficacy-efficiency of a large-field image intensifier in mass screening

Chest X-ray is the most frequent examination in radiology and accounts for a considerable portion of total population radiation exposure, mostly in screening programs. The ideal radiographic system is the one providing the best image quality together with the lowest dose to the patient, at a low cost. In this paper the authors analyze the potentials of a new chest X-ray examination unit equipped with a large-screen image intensifier (TS 57-Siemens). Two-thousand subjects were examined with this unit. The technical aspects of everyday practice are analyzed from the radiologist's point of view, together with the dose to the patient, image quality, and costs.     

Sonographic structural and morphological features of the parathyroid glands in patients on dialysis. Observations concerning 75 patients

The results of US study concerning parathyroid glands performed in 75 uremic patients on regular haemodialysis, examined by echography, are reported. The purpose of this research is the identification of the glands and the analysis of their sonographic features. The results show that parathyroids mostly have round shape and regular outlines, usually hypoechoic structure. The authors stress the use of US as a useful tool for visualization and anatomical definition of parathyroids, providing important information for surgical planning.