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Neurolymphomatosis is a rare manifestation of non-Hodgkin lymphoma characterized by infiltration of peripheral nerves, nerve roots, plexus and cranial nerves by malignant lymphocytes. This report presents positron emission tomography/computed tomography (PET/CT)imaging with 2-deoxy-2-(18)F-fluoro-D-glucose ((18)F-FDG) in 3 cases of non-Hodgkin lymphoma with nerve infiltration, including one newly diagnosed lymphoma, one recurrent lymphoma in previous nerve lesions and one newly recurrent lymphoma. PET/CT could reveal the affected neural structures including cranial nerves, spinal nerve roots, brachial plexus, cervicothoracic ganglion, intercostal nerves, branches of the vagus nerve, lumbosacral plexus and sciatic nerves. There was relative concordance between PET/CT and MRI in detection of affected cranial nerves. PET/CT seemed to be better than MRI in detection of affected peripheral nerves. (18)F-FDG PET/CT was a whole-body imaging technique with the ability to reveal the affected cranial nerves, peripheral nerves, nerve roots and plexus in non-Hodgkin lymphoma. A thorough understanding of disease and use of advanced imaging modalities will increasingly detect neurolymphomatosis.

In this study, we aimed to describe the characteristics of portal vein tumor thrombosis (PVTT), complicating hepatocellular carcinoma (HCC) in contrast-enhanced FDG PET/CT scan.

RATIONALE and OBJECTIVE: As both contrast and radiation dose affect the quality of CT images, a constant image quality in abdominal contrast-enhanced multi-detector CT (CE-MDCT) could be obtained balancing radiation and contrast media dose according to the age of the patients. MATERIALS AND METHODS: Seventy-two (38M;34F; aged 20-83 years) patients underwent a single-pass abdominal CE-MDCT. Patients were divided into three different age-groups: A(20-44 years); B (45-65 years); C (> 65 years). For each group, a different Noise Index (NI) and contrast media dose (370 mgI/mL) was selected as follows: A (NI=15; 2.5 mL/kg); B (NI =12.5; 2 mL/kg); C (NI=10; 1.5 mL/kg). Radiation exposure was reported as Dose Length Product (DLP) in mGy*cm. For quantitative analysis, Signal-to-Noise (SNR) and Contrast-to-Noise (CNR) ratios were calculated for both the liver (L) and the abdominal aorta (A). Statistical analysis was performed with a one-way ANOVA. Standard imaging criteria were used for qualitative analysis. RESULTS: Whereas peak hepatic enhancement was 152±16, 128±12 and 101±14 HU (p

Renal masses are a common finding in diagnostic imaging; these lesions usually are solid or cystic, benign or malignant, and the correct diagnosis may be difficult. The aim of our study was the comparison of multi-slice computed tomography (MSCT) and high-field magnetic resonance (MR) in the diagnostic evaluation of renal masses.We studied 29 patients, 16 men and 13 women aged 8-85 years (mean 61±17 years) with histo-cytological diagnosis of renal masses (n=31), of which the majority (74%; n=23) was represented by malignant lesions [renal cell carcinoma (Ca) =16, chromophobe renal cell Ca =2, squamous cell Ca =1, urothelial Ca =2, lymphoma =1, Wilms tumor =1]; the remaining 8 masses (26%) were benign (pyelonephritis =2, simple cyst =1, hematic cyst =1, lipoma =1 and oncocytoma =3). All patients underwent MSCT and MR (3.0 Tesla) before and after contrast injection; the images were evaluated in double-blind by two expert radiologists. The results of the images were then compared with the histo-cytological data to calculate the values of diagnostic accuracy for both methods in the identification and characterization of renal masses. The benign or malignant nature of the lesions was established according to the regularity of the margins, presence or absence of significant contrast enhancement, infiltration of perirenal fat and vascular invasion. The concordance of the results of the two imaging techniques was then calculated using the coefficient Kappa Cohen.For both identification and characterization of renal masses, MSCT and MR showed comparable values of diagnostic accuracy with a significant concordance (k=1); in particular, the diagnostic accuracy of MSCT/MR was 100%/100% for lesion identification, 90%/90% for lesion characterization in terms of benign or malignant nature, 97%/97% for the evaluation of lesion edges, 90%/90% for the assessment of lesion contrast enhancement, 93%/93% for the evaluation of peri-renal fat infiltration and 96%/96% for the evaluation of vascular infiltration. Only in three cases of oncocytoma the two imaging methods were both inaccurate for diagnosis of benignity classifying the lesions as probably malignant on the basis of the absence of central scar and of dynamic contrast enhancement pattern.The results of our study show comparable diagnostic accuracy of computed tomography (CT) and MR for the identification and characterization of expansive renal lesions. High-field MR is, therefore, a valid alternative to MSCT in the evaluation of renal masses avoiding exposure to ionizing radiation.

Cystic lymphangioma is a rare malformation characterized by cystic structure deriving from detachment of lymph sacs from venous drainage systems (1). The cystic variant of lymphangioma is included in the general classification of lymphangiomas according to Landing and Farber (2) enclosing the capillary and venous variant, characterized respectively by dilatation of capillary and sinusoidal lymphatic vessels (the latter with continued growth of the stromal component) which remain connected to the lymphatic network

Aims and objectives Methods and materials Results Conclusion Personal information References, Aims and objectives: Chemical-shift (CS) MR sequence has been demonstrated to be able to identify lipid-rich (typical) adrenal adenomas (1-2) , while T1-weighted (T1-W) dynamic sequence after gadolinium (Gd) has been proposed to characterize both typical and a-typical...

Objective: To assess the etiology, management and outcome of iliac pseudoaneurysms following renal transplantation. Methods: Eleven patients who underwent repair between 1982 and 2007 were identified. Five (Group 1) presented pseudoaneurysm at the anastomosis of the donor renal and native iliac arteries, and six (Group 2) presented iliac pseudoaneurysm following transplant nephrectomy. Intraoperative cultures and immunohistochemical examinations were obtained from all surgical cases to determine the existence of a relationship between infection or transplant rejection and pseudoaneurysm formation. Results: Endovascular repair (EVR) was used to treat three patients, while eight patients underwent open repair (OR). Transplant nephrectomy was needed in all cases but one after anastomotic pseudoaneurysm repair. After pseudoaneurysm excision, arterial reconstruction was performed in all cases, with a limb salvage rate of 100%. At 30 days, no patients died in the EVR subgroup. In the OR subgroup, one patient died of sepsis (12.5%). Cultures taken from the pseudoaneurysm wall and content grew Candida albicans and E. coli in two febrile patients. Pathologic evaluation of donor renal arteries revealed evidence of chronic rejection in three patients (60%) in Group 1, and in two (33.3%) in Group 2. No patients in either Group presented late infection, failure of vascular reconstruction nor pseudoaneurysm recurrence. The follow-up ranges from 20 to 89 months. Conclusions: The etiology of pseudoaneurysms in this location is multifactorial, however, an association with chronic rejection must be considered. Though rare, the development of pseudoaneurysms at the donor renal-external iliac artery anastomosis results in high rates of transplant nephrectomy. Less invasive endovascular techniques offer a new therapeutic option in this challenging scenario notwithstanding the fact that they require further validation. © 2009 Published by European Association for Cardio-Thoracic Surgery. All rights reserved.

The recent and wide innovation in diagnostic imaging has provided the availability of multiple and different techniques to evaluate patients with hypersecreting or non-hypersecreting adrenal tumours, such as anatomic modalities, mainly represented by computed tomography (CT) and magnetic resonance (MR), or functional studies consisting of radionuclide molecular scans. Furthermore, advanced hybrid imaging, currently represented by combined positron emission tomography (PET) and CT (PET-CT), is attractive and reflects the diagnostic significance of morpho-functional integrated imaging which simultaneously offers information regarding the anatomic characteristics and metabolic features of adrenal tumours. Since the fundamental clinical issue in such patients is tumour characterization for correct treatment planning, it is crucial to establish the correct selection of imaging techniques as well as imaging protocols according to patient clinical scenario, patient safety and cost-effectiveness performance of selected diagnostic approach; therefore, the appropriate management of such imaging modalities is clinically recommended.

The aim of this study was to determine the diagnostic performance of ultrasound (US) in the quantitative assessment of steatosis by comparison with proton magnetic resonance spectroscopy ((1)H-MRS) as a reference standard. Three liver echo-intensity indices were derived: US hepatic mean gray level, hepatic-renal echo-intensity ratio (H/R), and hepatic-portal blood echo-intensity ratio. The (1)H-MRS degree of steatosis was determined as percentage fat by wet weight. Regression equations were used to estimate quantitatively hepatic fat content. The hepatic fat content by (1)H-MRS analysis ranged from 0.10% to 28.9% (median value, 4.8%). Ultrasound H/R was correlated with the degree of steatosis on (1)H-MRS (R(2)= 0.92; P < .0001), whereas no correlation with (1)H-MRS was found for hepatic mean gray level and hepatic-portal blood echo-intensity ratio. A receiver operating characteristic curve identified the H/R of 2.2 as the best cutoff point for the prediction of (1)H-MRS of at least 5%, yielding measures of sensitivity and specificity of 100% and 95%, respectively. In this pilot study, US H/R exhibits high sensitivity and specificity for detecting liver fatty changes. Our results indicate that quantitative evaluation of hepatic fat content can be performed using US H/R and could therefore be a valuable analytic tool in clinical investigation.

Objective. The aim of this study was to compare the results of ultrasound (US), “whole-body” scintigraphy with iodine-131 (WBS) and PET with fluorine-18 deoxyglucose (FDG-PET) in patients with differentiated thyroid carcinoma (DTC) during the post-surgical follow-up. Materials and methods. Thirteen patients (3M, 10F) were evalueted by neck US, WBS and FDG-PET; all patients had near-total thyroidectomy. In each patient 6 anatomic regions (right and left thyroid beds, right and left cervical areas, right and left up-clavear compartments) were investigated for a total of 78 anatomic regions; distant metastases have been considered as a different group in the analysis and were investigated by WBS and FDG-PET. Imaging findings were compared with standard reference data such as: biopsy (n=4) or clinical-radiological (n=9) results. Results. In the neck, US, FDG-PET and WBS showed concordant results in the majority (91%) of sites of which 70 with no lesions, while in a patient with left cervical metastatic lymph node imaging results were concordant for abnormal findings; in the remaining 9% (n=7) of cases, imaging results were discordant; in particular, tumor lesions were detected only by US (n=3), by US and WBS (n=1) and only by FDG-PET (n=3). The detection of distant metastases by FDG-PET and WBS was concordant in the majority (77%) of patients as normal images (n=9), while in a case imaging result were concordant for the presence of tumor lesion. In the last three patients the results were discordant; in particular, in two patients only WBS detected distant metastases, while in the last patient only FDG-PET showed tumor lesion. Conclusions. Results of our work show a fundemental role of US for the evaluation of the neck in patient affected by DTC during the post-surgical follow-up. WBS is useful to determine the differentiation of tumor lesions, for the identification of the residual thyroid gland and for the search of distant metastases. FDG-PET has an important role in cases of undifferentiated DTC in which WBS and thyreoglobulin assay are not able to detect tumor lesions.

Background. The aim of this study was to evaluate the diagnostic accuracy of nor-cholesterol radionuclide imaging in patients with adrenal tumors detected by CT or MR imaging studies. Methods. We studied 41 patients (18 M and 23 F, mean age 47±15 years) with hypersecreting (n=19) or non-hypersecreting (n=22) unilateral adrenal tumors. All patients underwent iodine-131 nor-cholesterol adrenal scintigraphy. Pathology examinations (n=26) or CT follow-up studies (n=15) were obtained. Adrenal lesions were represented by 34 adenomas, 2 cysts, 1 myelolipoma, 1 pheochromocytoma, 1 carcinoma and 2 metastases. Radionuclide studies were qualitatively evaluated and the corresponding results were classified as true-positive (TP), true-negative, false-positive (FP) and false-negative. Diagnostic sensitivity, specificity and accuracy as well as positive (PPV) and negative (NPV) predictive values were calculated. In addition, nor-cholesterol uptake was semi-quantitatively compared between hypersecreting and non-hypersecreting adenomas using a four-point scoring. Results. The diagnostic values of nor-cholesterol scintigraphy to identify adrenal adenomas were: sensitivity 100%, specificity 71%, accuracy 95%, PPV 94% and NPV 100%; of note, 2 FP cases were observed represented by a pheochromocytoma and a myelolipoma, while no FN findings occurred. A significantly (p=0.01) higher nor-cholesterol uptake was observed in hypersecreting (n=19) adenomas compared to non-hypersecreting (n=15) lesions; however, no significant difference in tumor size was found in this comparative analysis. Conclusion. In the large majority of cases, adrenal scintigraphy using nor-cholesterol was able to characterize specific lesions as cortical adenomas. These findings show relevant clinical impact particularly in patients with non-hypersecreting adenomas; in this setting, laboratory data are not helpful for lesions characterization, while radionuclide abnormalities allow tumor-type identification. However, rare as well as unusual findings of adrenal scintigraphy may be observed since nor-cholesterol uptake was also found in two non-adenoma tumors (a myelolipoma and a pheochromocytoma). Finally, the lower nor-cholesterol uptake of non-hypersecreting adenomas might suggest a normal hormone synthesis of these lesions and, thus, regular secretion.

Purpose Methods and Materials Results Conclusion References Personal Information, Purpose: Renal masses represent a really common finding in a radiological daily practice; these lesions can be solid or cystic, benign or malignant, and sometimes the exact diagnosis can be difficult. The aim of our study was to compare multi-slice CT and...

Purpose Methods and Materials Results Conclusion References Personal Information, Purpose: The most appropriate tools in diagnostic imaging for the characterization of focal liver lesions (FLL) are ultrasonography (US), computed tomography (CT) and magnetic resonance (MR); in particular, MR imaging is currently the method of choice as it...

Purpose Methods and Materials Results Conclusion References Personal Information, Purpose: Adrenal adenomas are the most common adrenal benign lesions detected on pathological studies in about 6% of patients over 60 years of age (1). The predominant characteristic of adrenal adenomas is the fatty content; because of this property, adrenal...

Purpose Methods and Materials Results Conclusion References Personal Information, Purpose: The aim of this study was to evaluate the role of MRCP compared with US and MSCT in diagnosing pancreaticobiliary disease; we performed a comparative analysis of imaging results in the main regions of the pancreaticobiliary system...

Purpose Methods and Materials Results Conclusion References Personal Information, Purpose: To compare metaiodobenzylguanidine (MIBG) uptake and magnetic resonance (MR) signal intensity ratio in differentiating benign and malignant disease in patients with pheochromocytoma or...

Purpose Methods and Materials Results Conclusion References Personal Information, Purpose: The aim of this study was to directly compare the results of nor-cholesterol scintigraphy and those of MR imaging in characterizing adrenal adenomas to differentiate between hypersecreting and non-hypersecreting...

INTRODUCTION: Magnetic Resonance Imaging (MRI) has been proposed as the diagnostic technique of choice to characterize adrenal tumors. However, the results of the current studies are controversial. MATERIAL AND METHODS: Forty-nine patients with unilateral adrenal masses were submitted to MRI for lesion characterization on the basis of MR signal intensity. Cytology and/or histology demonstrated 14 pheochromocytomas (pheos), 11 adenomas, 3 cysts, 2 myelolipomas, 4 carcinomas, 3 metastases and 1 fibrosarcoma; a clinical diagnosis of adenoma was made in the remaining 11 patients. MR studies were performed using spin-echo (SE) sequences with T1 (TR/TE = 600/17 ms) and T2 (TR/TE = 2000/15-90 ms) weighting. T1-weighted images were also acquired after Gadolinium-DTPA (Gd-DTPA) administration. MR studies were integrated with in- and out-of-phase (TR/TE = 100/4-6 ms) chemical-shift (CS) sequences. MR signal intensity (SI) was analyzed qualitatively and quantitatively; MR results were correlated with tumor type and hormone secretion. RESULTS: The qualitative analysis of T2 images showed high signal intensity in the majority (80%) of adrenal lesions (14 pheos, 12 adenomas, 3 cysts, 2 myelolipomas and 8 malignancies). The quantitative analysis of post-Gd-DTPA T1 images permitted to distinguish adenomas, cysts and myelolipomas from pheos and malignancies. The qualitative analysis of post-Gd-DTPA T2 and T1 images permitted to distinguish pheos and cysts from adenomas and malignancies (p < .05); however, pheos and cysts as well as adenomas and malignancies were not differentiated. MR SI was similar in secreting and nonsecreting adenomas from both a qualitative and a quantitative viewpoints. CS MRI permitted to distinguish adenomas (decreased signal intensity on out-phase relative to in-phase images) from other benign and malignant lesions (no signal change from out-phase to in-phase images). CONCLUSIONS: The qualitative analysis of MR SI on conventional T1 and T2 images does not permit to differentiate adrenal masses. The qualitative evaluation of T1 images after Gd-DTPA administration, the quantitative analysis and CS sequences are technical options improving lesion characterization.

123I-radiolabeled metaiodobenzylguanidine (123I-MIBG) cardiac imaging has been used to evaluate the distribution of sympathetic nervous system (SNS) in the heart. Different heart diseases have shown impaired cardiac SNS distribution as reflected by MIBG activity. The aim of this study was to assess the cardiac distribution of SNS in normal subjects, using MIBG imaging. Ten normal subjects (1 male and 9 females, mean age 46 +/- 9 years) with no cardiac abnormalities underwent myocardial 123I-MIBG scintigraphy, Tc-99m methoxyisobutylisonitrile (MIBI) cardiac perfusion imaging and equilibrium radionuclide angiography (RNA). Regional myocardial MIBG and MIBI activities were quantitatively evaluated using a region of interest analysis. For this purpose, the left ventricle was divided into 6 myocardial regions as anterior, apical, inferior, septum, lateral and posterolateral. In particular, myocardial MIBG and MIBI activities were measured as myocardium to mediastinum ratio. Regional left ventricular function was assessed by RNA. Myocardial MIBG uptake was homogeneous in anterior (2.2 +/- 0.5), inferior (2.5 +/- 0.7), septal (2.4 +/- 0.4), lateral (2.3 +/- 0.4), and posterolateral (2.3 +/- 0.4) regions. Conversely, MIBG uptake was significantly lower in the apical region (1.9 +/- 0.3) compared to all other left ventricular segments (p < 0.05). Regional myocardial perfusion, as measured by MIBI uptake, was homogeneous in all regions. No regional left ventricular wall motion abnormalities were observed by RNA. In conclusion, our data suggest that a decreased MIBG uptake may be observed in the left ventricular apical region of normal subjects reflecting reduced sympathetic innervation of the apex. This finding is not related to myocardial perfusion or wall motion abnormalities. The knowledge of cardiac sympathetic innervation in normal subjects may be helpful to assess SNS abnormalities in heart disease.