Pietro Andrea Bonaffini

Quantitative evaluation of CT-perfusion map as indicator of tumor response to transarterial chemoembolization and radiofrequency ablation in HCC patients.

PURPOSE To assess if radiofrequency ablation (RFA) and transarterial chemoembolization (TACE) may influence the evaluation of perfusion parameters obtained with CT-perfusion (CT-p) in HCC treated patients. MATERIALS AND METHODS Thirty-three consecutive cirrhotic patients with biopsy-proven diagnosis of HCC lesions and candidates to TACE or RFA were included. The CT-p study of hepatic parenchyma and of treated lesions was performed about 1 month after treatment on 16 multidetector CT after injection of 50mL of non ionic contrast agent (350mg I/mL) at a flow rate of 6mL/s acquiring 40 dynamic scans. A dedicated perfusion software which generated a quantitative map of arterial and portal perfusion by means of colour scale was employed.The following perfusion parameters were assessed before and after RFA or TACE treatment: hepatic perfusion (HP), arterial perfusion (AP), blood volume (BV), time to peak (TTP), hepatic perfusion index (HPI). RESULTS A complete treatment was obtained in 16 cases and incomplete treatment in the 17 remaining cases. The perfusion data of completely treated lesions were: HP 10.2±6.3; AP 10.4±7; BV 4.05±4.8; TTP 38.9±4.2; HPI 9.9±9.2, whereas in partially treated lesions were: HP 43.2±15.1mL/s/100g; AP 38.7±8.8mL/min; BV 20.7±9.5mL/100mg; TTP 24±3.7s; HPI 61.7±7.5%. In adjacent cirrhotic parenchyma, the parameters of all evaluated patients were: HP 13.2±4; AP 12.3±3.4; BV 11.8±2.8; TTP 43.9±2.9; and HPI 17.1±9.8. A significant difference (P<0.001) was found for all parameters between residual viable tumor tissue (P<0.001) compared to successfully treated lesion due to the presence of residual arterial vascular structure in viable portion of treated HCC. CONCLUSION According to our results, CT-p evaluation is not influenced by TACE or RFA treatments, thus representing a feasible technique that allows a reproducible quantitative evaluation of treatment response in HCC patients.

Diagnostic value of whole-body low-dose computed tomography (WBLDCT) in bone lesions detection in patients with multiple myeloma (MM)

PURPOSE To assess the role of whole-body low-dose computed tomography (WBLDCT) in the diagnosis and staging of patients with suspicion of multiple myeloma (MM). MATERIALS AND METHODS A total of 138 patients (76 male and 62 female; mean age 63.5 years, range 50-81 years), with early MM, underwent WBLDCT protocol study, performed on 16-slice scanner (Brilliance, Philips Medical System, Eindhoven, The Netherlands): tube voltage 120 kV; tube current time product 40 mAs. Diagnosis of osteolytic lesions was performed on the basis of axial and multiplanar reformatted images, whereas the assessment of spinal misalignment and fracture was done by using multiplanar reformatted images. The overall dose delivered to each patient was 4.2 mSv. Every patient gave personal informed consent, as required by our institution guidelines. RESULTS The diagnosis was established either by histopathology or imaging follow-up (size increase of over a period time). In all 138 patients, image resolution was diagnostic, enabling correct classification of multiple myeloma patients. WBLDCT showed a total of 328 pathologic bone findings in 81/138 patients. CT scanning resulted in complete evaluation of the bone lesions in these areas of the skeleton: skull (42), humerus (15), femur (20), ribs (7), scapulae (13), pelvis (35), clavicle (13), sternum (10), cervical (39), dorsal (65), lombar (48) and sacral rachis (21). In 40/81 bone involvement detected by CT was the only CRAB criterion present. Furthermore, WBLDCT demonstrated pleuro-pulmonary lesions in 20 patients (11 infective, 9 as MM localizations) and 1 renal neoplasia. CONCLUSION WBLDCT, detecting bone marrow localizations and demonstrating extra-osseous findings, with a fast scanning time and high resolution images, is a reliable imaging-based tool for a proper management of MM patients.

Low kV settings CT angiography (CTA) with low dose contrast medium volume protocol in the assessment of thoracic and abdominal aorta disease: a feasibility study

OBJECTIVE To assess the diagnostic quality of low dose (100 kV) CT angiography (CTA), by using ultra-low contrast medium volume (30 ml), for thoracic and abdominal aorta evaluation. METHODS 67 patients with thoracic or abdominal vascular disease underwent multidetector CT study using a 256 slice scanner, with low dose radiation protocol (automated tube current modulation, 100 kV) and low contrast medium volume (30 ml; 4 ml s(-1)). Density measurements were performed on ascending, arch, descending thoracic aorta, anonymous branch, abdominal aorta, and renal and common iliac arteries. Radiation dose exposure [dose-length product (DLP)] was calculated. A control group of 35 patients with thoracic or abdominal vascular disease were evaluated with standard CTA protocol (automated tube current modulation, 120 kV; contrast medium, 80 ml). RESULTS In all patients, we correctly visualized and evaluated main branches of the thoracic and abdominal aorta. No difference in density measurements was achieved between low tube voltage protocol (mean attenuation value of thoracic aorta, 304 HU; abdominal, 343 HU; renal arteries, 331 HU) and control group (mean attenuation value of thoracic aorta, 320 HU; abdominal, 339; renal arteries, 303 HU). Radiation dose exposure in low tube voltage protocol was significantly different between thoracic and abdominal low tube voltage studies (490 and 324 DLP, respectively) and the control group (thoracic DLP, 1032; abdomen, DLP 1078). CONCLUSION Low-tube-voltage protocol may provide a diagnostic performance comparable with that of the standard protocol, decreasing radiation dose exposure and contrast material volume amount. ADVANCES IN KNOWLEDGE Low-tube-voltage-setting protocol combined with ultra-low contrast agent volume (30 ml), by using new multidetector-row CT scanners, represents a feasible diagnostic tool to significantly reduce the radiation dose delivered to patients and to preserve renal function, while also maintaining adequate diagnostic quality images in assessment of aorta.

Apparent Diffusion Coefficient Maps Integrated in Whole-Body MRI Examination for the Evaluation of Tumor Response to Chemotherapy in Patients with Multiple Myeloma

RATIONALE AND OBJECTIVES To determine the diagnostic value of apparent diffusion coefficient (ADC) maps in the assessment of response to chemotherapy in patients with multiple myeloma (MM). MATERIALS AND METHODS Fourteen patients (seven women) with MM underwent whole-body magnetic resonance imaging (WB-MRI) study on a 1.5T scanner, before and after chemotherapy. DWI with background body signal suppression (DWIBS) sequences (b values: 0, 500, and 1000 mm(2)/sec) were qualitatively analyzed, along with T1 turbo spine echo and short tau inversion recovery T2-weighted images, to evaluate bone lesions. On ADC maps, regions of interest were manually drawn along contours of lesions. The ADC values percentage variation (ΔADC) before (MR1) and after (MR2) chemotherapy were calculated and compared between responders (11 of 14) and nonresponders (3 of 14). The percentage of plasma cells by the means of the bone marrow aspirate was evaluated as parameter for response to chemotherapy. RESULTS Twenty-four lesions, hyperintense on DWIBS as compared to normal bone marrow, were evaluated. In responder group, the mean ADC values were 0.63 ± 0.24 × 10(-3) mm(2)/s on MR1 and 1.04 ± 0.46 × 10(-3) mm(2)/s on MR2; partial or complete signal intensity decrease during follow-up on DWIBS was found along with a reduction of plasma cells infiltration in the bone marrow. The mean ADC values for nonresponders were 0.61 ± 0.05 × 10(-3) mm(2)/s on MR1 and 0.69 ± 0.09 × 10(-3) mm(2)/s on MR2. The mean variation of ΔADC in responders (Δ = 66%) was significantly different (P < .05) than in nonresponders (Δ = 15%). CONCLUSIONS WB-MRI with DWIBS sequences, by evaluating posttreatment changes of ADC values, might represent a complementary diagnostic tool in the assessment of response to chemotherapy in MM patients.

CT enterography: Diagnostic value of 4th generation iterative reconstruction algorithm in low dose studies in comparison with standard dose protocol for follow-up of patients with Crohn’s disease

PURPOSE To compare radiation dose, image quality and diagnostic performance of low dose CT enterography (CTE) protocol combined with iterative reconstruction algorithm (iDose(4)) with standard dose CTE in follow-up of patients with known Crohns disease (CD). MATERIALS AND METHOD Thirty-six patients (12 females), with CD underwent a low-dose CTE scan during single venous phase on 256 MDCT scanner, with the following parameters: 120 kV, automated mAs dose-modulation, slice thickness 2mm and iDose(4) iterative reconstruction algorithm. A control group of thirty-seven patients underwent standard dose CTE examination on the same CT scanner. Two radiologists, blinded to clinical and pathological findings, independently evaluated in each scan, HU values in bowel wall and any presence of CD activity features and disease complications. Image noise and diagnostic quality were evaluated using a 4-point scale. Dose-length product (DLP) and CT-dose-index (CTDI) were recorded and data from both examinations were compared and statistically analyzed. RESULTS Low-dose CTE protocol showed high diagnostic quality in assessment of Crohns disease obtaining significantly (p ≤ 0.001) lower values of DLP and CTDI (604.98 mGy*cm and 12.29 mGy) as compared to standard dose examinations (974.85 mGy*cm and 19.71 mGy), with an overall dose reduction of 37.6%. Noise resulted slightly higher in iDose(4) images (SD=15.97) than in standard dose ones (SD=13.61) but this difference was not statistically significant (p=0.064). CONCLUSION Low-dose CTE combined with iDose(4) reconstruction algorithm offers high quality images with significant reduction of radiation dose, and therefore can be considered a useful tool in the management of CD patients, considering their young age and the frequent imaging follow-up required.

Semiquantitative perfusion combined with diffusion-weighted MR imaging in pre-operative evaluation of endometrial carcinoma: Results in a group of 57 patients

PURPOSE To evaluate the semiquantitative DCE and quantitative DWI parameters in endometrial cancer, in order to assess the presence of neoplastic tissue and normal myometrium and to ascertain a potential relationship with tumor grade. METHODS AND MATERIALS A total of 57 patients with biopsy-proven endometrial adenocarcinoma who underwent MR imaging examination for staging purposes were retrospectively evaluated. Imaging protocol included multiplanar T1- and T2-weighted TSE, DCE T1-weighted (THRIVE; 0, 30, 90 and 120seconds after intravenous injection of gadolinium) and DWIBS sequences (b values=0 and 1000mm(2)/s). Color perfusion and ADC maps were automatically generated on dedicated software. Relative enhancement (RE, %), maximum enhancement (ME, %), maximum relative enhancement (MRE, %), time to peak (TTP, s) and mean apparent diffusion coefficient (ADC) were calculated by manually drawing a region of interest (ROI) both on the neoplastic tissue and the normal myometrium. Histopathology was used as reference standard. RESULTS Histopathological analysis confirmed the presence of endometrial carcinoma in all patients. Neoplastic tissue demonstrated significantly lower (P<0.001) values of RE (%) 63.92±35.68; ME (%) 864.91±429.54 and MRE (%) 75.97±38.26 as compared to normal myometrium (RE (%) 151.43±55.99; ME (%) 1800.73±721.32; MRE (%) 158.28±54.05). TTP was significantly higher (P<0.05) in tumor lesion (385.51±1630.27 vs 195.44±78.69). Mean ADC value of neoplastic tissue (775.09±?220.73×10(-3)mm(2)/s) was significantly lower (P<0.05) than in myometrium (1602.37±378.54×10(-3)mm(2)/s). The analysis of perfusion and diffusion parameters classified according to tumor grades, showed a statistically significant difference only for RE (P=0.043) and ME (P=0.007). CONCLUSIONS Perfusion parameters and mean ADC differ significantly between endometrial cancer and normal myometrium, potentially reflecting the different microscopical features of cellularity and vascularity; however a significant relationship with tumor grade was not found in our series.

Diagnostic Accuracy of 256-Detector Row Computed Tomography in Detection and Characterization of Incidental Pancreatic Cystic Lesions

Purpose. To assess the diagnostic value of 256-detector row MDCT in the characterization of incidentally detected pancreatic cystic lesions (PCLs). Materials and Methods. We retrospectively reviewed 6389 studies performed on a 256-row detector scanner, wherein ≥1 PCLs were incidentally detected. Images from a total of 192 patients (99 females; age range 31–90 years) were analysed referring to morphologic predictive signs of malignancy, including multifocality, inner septa, wall thickening, and mural enhancing nodules. Results. We evaluated 292 PCLs in 192 patients (solitary in 145 and ≥2 in 47; incidence 2.05%). Size ranged from 3 to 145 mm (mean 15 mm); body was the most common location (87/292; 29.8%). Intralesional septa were detected in 52/292 lesions (17.8%), wall thickening >2 mm in 13 (4.5%), enhancing wall and mural nodules in 15 (5.1%) and 12 (4.1%), respectively. Communication with ductal system was evident in 45 cases. The most common diagnoses, established by histology or imaging analysis, were IPMNs (about 86%), while serous cystic neoplasia (3.7%) and metastases (0.5%) were the less common. Conclusion. MDCT provides detailed features for characterization of PCLs, which are incidentally discovered with increased frequency due to the widespread use of cross-sectional imaging.

Diagnostic Value of Semiquantitative Analysis of Dynamic Susceptibility Contrast Magnetic Resonance Imaging with GD-EOB-DTPA in Focal Liver Lesions Characterization: A Feasibility Study

Purpose. To assess the diagnostic accuracy of dynamic susceptibility contrast-enhanced magnetic resonance imaging (DSCE-MRI) in differentiation between benign and malignant liver lesions by assessment of tumoral perfusion parameters. Methods Materials. Seventy-three patients with known focal liver lesions, including 45 benign (16 FNH, 27 angiomas, and 2 abscesses) and 28 malignant ones (17 metastases, 9 HCCs, and 2 cholangiocarcinoma) underwent 1.5 T MRI upper abdominal study, with standard protocol that included dynamic contrast-enhanced sequences. On dedicated workstation, time-intensity curves were determined and the following perfusion parameters were calculated: relative arterial, venous and late enhancement (RAE, RVE, RLE), maximum enhancement (ME), relative enhancement (RE), and time to peak (TTP). Results. All diagnoses were established either by histopathology or imaging follow-up. Perfusion mean values calculated in benign lesions were RAE 33.8%, RVE 66.03%, RLE 80.63%, ME 776.00%, MRE 86.27%, and TTP 146.95 sec. Corresponding perfusion values calculated in malignant lesions were RAE 22.47%, RVE 40.54%, RLE 47.52%, ME 448.78%, MRE 49.85%, and TTP 183.79 sec. Statistical difference (p < 0.05) was achieved in all the perfusion parameters calculated, obtaining different cluster of perfusion kinetics between benign and malignant lesions. Conclusions. DSCE-MRI depicts kinetic differences in perfusion parameters among the different common liver lesions, related to tumour supply and microvascular characteristics.

Duodenocaval Fistula in a Patient with Inferior Vena Cava Leiomyosarcoma Treated by Surgical Resection and Caval Polytetrafluoroethylene Prosthesis.

Inferior vena cava (IVC) leiomyosarcoma represents an extremely rare disease that commonly involves the segment between the inflow of the renal veins and the inflow of the hepatic veins (46% of cases). We report the case of a patient affected by an IVC leiomyosarcoma, treated with surgical resection, caval reconstruction with polytetrafluoroethylene (PTFE), and right nephrectomy, followed by external beam radiotherapy. Oncological follow-up was negative for 17 years after this combined treatment, since the patient developed a duodenocaval fistula (DCF).

Relative volume measured with magnetic resonance imaging is an articular collapse predictor in hematological pediatric patients with femoral head osteonecrosis.

AIM To assess the potential value of femoral head (FH) volume measurements to predict joint collapse, as compared to articular surface involvement, in post-treatment osteonecrosis (ON) in pediatric patients affected by lymphoproliferative diseases. METHODS Considering 114 young patients with lymphoproliferative diseases undergone a lower-limbs magnetic resonance imaging (MRI) examination between November 2006 and August 2012 for a suspected post-treatment ON, we finally considered a total of 13 cases (7 males, mean age 15.2 ± 4.8 years), which developed a FH ON lesions (n = 23). The MRI protocol included coronal short tau inversion recovery and T1-weighted sequences, from the hips to the ankles. During the follow-up (elapsed time: 9.2 ± 2 mo), 13/23 FH articular surface (FHS) developed articular deformity. The first MRI studies with diagnosis of ON were retrospectively analyzed, measuring FH volume (FHV), FHS, ON volume (ONV) and the articular surface involved by ON (ONS). The relative involvement of FHS, in terms of volume [relative volume (RV): ONV/FHV] and articular surface [relative surface (RS): ONS/FHS], was then calculated. RESULTS By using receiver operating characteristic curve analysis (threshold of 23% of volume involvement), RV predicted articular deformity in 13/13 FHS [sensitivity 100%, specificity 90%, accuracy 95%, positive predictive value (PPV) 93%, negative predictive value (NPV) 100%]. Considering a threshold of 50% of articular involvement, RS predicted articular deformity in 10/13 femoral heads (sensitivity 77%, specificity 100%, accuracy 87%, PPV 100%, NPV 77%). CONCLUSION RV might be a more reliable parameter than RS in predicting FH deformity and could represent a potential complementary diagnostic tool in the follow-up of femoral heads ON lesions.