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Abstract: Branch duct intraductal papillary mucinous tumors (IPMTs) are increasingly being described and represent a challenge for the physician. If on one hand the most recent imaging modalities, especially CT and MR, allow for a correct diagnosis, on the other IPMTs can manifest with different degrees of cellular atypia and therefore it is really important to be able to establish the biological behavior of the lesion. Sixty-five patients were included in this study: 29 of them underwent surgery, while the other 36 were followed-up with cross-sectional imaging. Among the patients submitted to surgery, 11 had benign lesions and 18 malignant lesions. The overall values of sensitivity, specificity, and accuracy in the diagnosis of malignancy for all the cross-sectional imaging techniques were, respectively, 61%, 81%, and 69%. Among the followed-up patients, who had an MRCP diagnosis of branch duct IPMT with imaging features indicative of benignity, only two showed modifications over the follow-up period. Even considering some important biases (small number of patients, relatively short follow-up), interesting conclusions can be drawn: the imaging diagnosis of malignancy is trustable, while that of benignity cannot be relied upon, but if the signs of malignancy are absent the slow growth of the lesions justifies watchful follow-up in the correct clinical setting.

La pancreatitis autoinmune (PAI) es una forma distinta de pancreatitis crónica, que se caracteriza por un mecanismo patogénico autoinmune. Su frecuencia es levemente mayor en los pacientes de sexo masculino (60%) y la edad promedio de presentación oscila entre los 40 y 60 años, aunque el rango etario es mucho más amplio (de 14 a 80 años). Desde el punto de vista histológico, la PAI se presenta con un infiltrado inflamatorio denso, de extensión variable, que puede ser focal o comprometer difusamente todo el páncreas. Su presentación clínica en la mayoría de los casos es inespecífica: dolor abdominal leve y rara vez síntomas de pancreatitis aguda, pérdida de peso o ictericia. Varios estudios han descrito un compromiso multiorgánico por el proceso autoinmune, indicando la naturaleza sistémica de la enfermedad.

We propose an innovative tool for Pancreatic Ductal AdenoCarcinoma 3D reconstruction from Multi-Detector-Computed Tomography. The tumor mass is discriminated from health tissue, and the resulting segmentation labels are rendered preserving information on different hypodensity levels. The final 3D virtual model includes also pancreas and main peri-pancreatic vessels, and it is suitable for 3D printing. We performed a preliminary evaluation of the tool effectiveness presenting ten cases of Pancreatic Ductal AdenoCarcinoma processed with the tool to an expert radiologist who can correct the result of the discrimination. In seven of ten cases, the 3D reconstruction is accepted without any modification, while in three cases, only 1.88, 5.13, and 5.70 %, respectively, of the segmentation labels are modified, preliminary proving the high effectiveness of the tool.

Backgrounds and aims: We assessed the associations between pancreatic fat accumulation and other fat compartments, including liver fat and visceral adipose tissue as well as insulin resistance and other metabolic abnormalities in obese individuals. Subjects and methods: We studied 42 Caucasian adults with obesity [20 men and 22 women; mean body mass index (BMI) 35.2±4 kg/m2], who had no history of liver diseases or excessive alcohol consumption, in which subcutaneous, visceral, liver, and pancreatic fat contents were quantified by an in-opposed-phase magnetic resonance imaging (MRI) technique. Results: Compared with patients in the lower tertile (<5.6%, no.=15), those in the upper tertile of liver fat content had more visceral adipose tissue, greater insulin resistance and had higher values of BMI, blood pressure, triglycerides and lower HDL-cholesterol and adiponectin. Notably, pancreatic fat accumulation also significantly increased across tertiles of liver fat content. In univariate analysis, the strongest correlates of pancreatic fat were visceral and liver fat contents (r=0.80 and r=0.54, p<0.001–0.0001, respectively). Pancreatic fat accumulation was also moderately associated with insulin resistance and other metabolic syndrome features. However, when adjusted for age, gender and visceral adipose tissue, the associations of pancreatic fat accumulation with liver fat and other metabolic abnormalities were no longer significant. Conclusions: There are significant associations between pancreatic fat accumulation and liver fat content as well as insulin resistance and other metabolic abnormalities in obese, but otherwise healthy, individuals. However, these associations are largely mediated by the amount of visceral adipose tissue.

White matter lesions (WMLs) are commonly found on brain MRI of migraine patients. Migraine with aura (MA) is associated with an increased frequency of right-to-left shunt (RLS) mostly due to patent foramen ovale. The relationship between WML load and RLS in MA is currently unknown.

Purpose:To assess the technical and clinical success of endovascular treatment of arterial bleeding in pancreatitis. Materials and Methods:From 1992 to 2005, 28 patients with pancreatitis underwent endovascular treatment of associated arterial lesions. Fifteen patients were affected by acute pancreatitis and 13 by chronic pancreatitis. The diagnosis was obtained according to medical history and clinical and laboratory evidence of disease. Arterial involvement was diagnosed by non-invasive imaging and angiography. After treatment, all patients underwent CT scanning at a minimum of 15, 30 and 90 days. We evaluated the feasibility of embolization and patients' survival at 90 days. Results:Transcatheter embolization was feasible in 26/28 patients (93%). In 2 patients with acute pancreatitis, selective catheterization failed so we could not proceed with the angiographic approach. After treatment, there were 3/26 rebleeds (11.5%), all of whom died within the first week. At 90 days' follow-up, 21/26 patients (81%) were alive. Two of 26 patients (8%) suffered splenic complications. Among the 13 patients with acute pancreatitis, 8 (61.5%) were alive after 90 days. All 13 patients with chronic pancreatitis were alive after 90 days. Conclusions:Comparing our results with the surgical literature, we found that embolization is less invasive and, at least, as successful as surgery. Thus, it should be considered the first choice in pancreatitis arterial complications.

IV methylprednisolone (IVMP) has been used to treat relapses in patients with relapsing-remitting (RR) MS, but its effect on disease progression is not known. Furthermore, there are no data on the impact of IVMP on T1 black holes or whole-brain atrophy.

Abstract: Correlation studies between various conventional and non-conventional MRI parameters and cognitive impairment in the early stages of multiple sclerosis (MS) are lacking, although it is known that a number of patients with early MS have mild cognitive impairment. Our aim was to explore whether this cognitive impairment is dependent on the extent and severity of the burden of disease, diffuse microscopic brain damage or both. We studied 63 patients with clinically definite relapsing-remitting (RR) MS, duration of disease 1–10 years and Expanded disability status scale scores ≤ 5.0. Mean age was 35.4 years, mean duration of disease 5.8 years and median EDSS score 1.5. Neuropsychological performance, psychological function, neurological impairment and disability were assessed. The patients also underwent MRI, including magnetisation-transfer (MT) studies. We quantified the lesion load on T2- and T1-weighted images, the magnetisation transfer ratio (MTR) of normal-appearing brain tissue (NABT) and the brain parenchymal fraction (BPF). No significant difference was found between lesion loads in patients with and without cognitive impairment. In 15 patients (23.8 %) with overall cognitive impairment, median BPF and average NABT MTR were significantly lower than those in patients without cognitive impairment (0.868 vs 0.892, P = 0.02 and 28.3 vs 29.7 P = 0.046, respectively). Multiple regression analysis models demonstrated that the only variables independently correlated with cognitive impairment were: BPF (R = 0.89, P = 0.001) and average NABT MTR (R = 0.76, P = 0.012). Our findings support the hypothesis that, cognitive decline in patients with MS, a low disability score and short duration of disease is directly associated with the extent and severity of diffuse brain damage. The loss of brain parenchyma did not correlate with the severity of microscopic damage in the NABT, indicating that the two processes could be distinct in the early stages of the disease.

The computed tomographic features of calcification in the eye were correlated with clinical and pathological findings in a variety of ophthalmic and systemic disorders. These consisted of ocular neoplasms, trauma and inflammation of the eye, idiopathic ocular lesions, and disorders of calcium metabolism. Computed tomographic documentation of ocular calcification was found to be useful in the differential diagnosis and management of patients with these disorders.

Primary panhypopituitarism consists of functional deficiency of the anterior pituitary lobe, which appears during infancy or adolescence. The magnetic resonance findings in 10 patients with a history of primary hopopituitarism are presented. The findings include: reduced pituitary size in all cases: partially (8 cases) or totally (2 cases) empty sella; thin (4 cases), partially visible (3 cases) or absent (2 cases) pituitary stalk; absence of the posterior lobe in 9 cases: bright spot corresponding to an ectopic posterior lobe in 8 cases. These findings are similar to those already reported in pituitary dwarfism and may help under-genesis of the pathogenesis of the disease: which seems to he related to a pituitary stalk lesion.

Previous work of Petrovic et al. (1982) demonstrated the possibility of using x-ray transmission, computed tomography (CT) scanning for soil bulk density analysis in soil. We show that CT can also be used for measuring the water content of soil. We also show that CT can be applied to measure and follow dynamically the motion of water in soil in three dimensions. Furthermore inhomogeneities of water content and motion in soil can be observed with this technique. Using a third-generation CT scanner, several different techniques can be applied, such as differential, real-time, and spatial distribution scanning modes. A linear dependence was demonstrated for the Hounsfield units (HU) used in CT and water content. The use of CT for water content and motion in soil in three dimensions opens new possibilities in this area of investigation.

MRI contrast between white and grey matter appears to be higher in young normal subjects than in older patients. The aim of the present study was to investigate the possible relationships between these changes in contrast and ageing. It consisted of two parts. In the first part we retrospectively evaluated 140 MRI brain examinations of healthy subjects, 20 per decade (age range 20–90 years), in whom the contrast was subjectively scored. In the second part we prospectively measured the actual T1, spin density (SD) and T2 values of white and grey matter in another 22 healthy subjects (age range 20–80 years). In the first group of subjects a progressive decrease in white/grey matter contrast was observed with ageing. In the second group of subjects the T1, SD and T2 values of white matter were always shorter than those of grey matter. There is a close relation among T1, SD and T2 values of white and grey matter with ageing. We suggest that there is a progressive loss of white/grey matter contrast with ageing. Such a phenomenon is possibly due to an increased water content in the white matter and the progressive neuronal loss in the grey matter that occurs with age.

Twenty-six patients with a clinical diagnosis of spondylodiscitis were examined with non-contrast and contrast-enhanced MRI in order to define the contribution of gadolinium-DTPA (Gd-DTPA) and different pulse sequences, including a fat suppression sequence (SPIR). Spin echo (SE) T1-weighted images before and after Gd-DTPA injection and SE T2-weighted images were obtained in all patients. Twelve patients were also examined using the SPIR sequence following Gd-DTPA injection. Signal intensity and morphological features of the disc and vertebral lesions were then evaluated. The SE T1-weighted sequence with Gd-DTPA was very effective in showing the pathological changes at the level of the disc as an area of low signal intensity surrounded by a peripheral rim of enhancement in 24 of 26 cases (92%). This feature was not visible on non-enhanced images. As regards contiguous vertebral lesions this sequence was less informative, since in 8 of 26 cases (31%) the vertebral lesions became isointense and therefore not detectable. In 12 cases there was extension into the surrounding structures (spinal canal and/or paravertebral tissues). An enhanced SE T1-weighted sequence provided good anatomical definition of the extension of the infection in the spinal canal in all cases with this type of involvement (7 of 12). Regarding the 7 cases with paravertebral extension, no extension was visible in 1 case due to the reduced contrast with the surrounding fat following Gd-DTPA injection. The enhanced SPIR sequence was very effective, particularly in detecting the lesions in the vertebral bodies, avoiding the limitation of the enhanced SE T1-weighted sequence. The SPIR sequence was also effective in showing the extension within the spinal canal and the paravertebral fat. On the basis of our results the combination of a SE T1-weighted sequence without contrast and SPIR sequence with Gd-DTPA seems to be the best approach in cases of spondylodiscitis.

Meningeal cysts (MC) are rare extensions of the meninges and are diverticula of the spinal meningeal sac, nerve root sheath or arachnoid that contain cerebrospinal fluid (CSF). They communicate with the subarachnoid space (SAS). The aim of this study was to demonstrate the MRI findings and to emphasise the contribution of MRI to the diagnosis of this rare pathology. MRI findings were evaluated according to a new classification that divides MCs into extradural cysts without (type 1) or with (type 2) spinal nerve root fibres and intradural cysts (type 3). Because of its high contrast resolution MRI can distinguish the three types of MC. The use of the different levels of signal intensity of the cyst and CSF in T2-weighted images to distinguish communicating from non-communicating MCs is illustrated. This diagnostic sign exploitats the signal loss due to flow phenomena of CSF pulsations on ungated sequences to reveal the communication of the MC with the SAS. We recommend MRI as the most sensitive and specific modality for the study of MCs.

Renal sarcomas and sarcomatoid renal cell carcinomas are extremely rare neoplasms of the kidney. The Authors reviewed the pathological files and report the features of 12 renal sarcomas and 22 sarcomatoid carcinomas. Leiomyosarcomas and liposarcomas were the most common tumors among the sarcomas, while sarcomatoid carcinomas presented different proportions of carcinomatous and sarcomatous elements. The findings of diagnostic imaging modalities, including plain film and intravenous urography (with nephrotomography), arteriography, ultrasonography and computed tomography, are reported. The findings enable the diagnosis of the nature of these masses. However, the actual experience does not allow a prospective diagnosis of renal sarcoma or of sarcomatoid carcinoma. The mesenchymal nature of the tumor may be suspected when the capsular or sinusal origin is evident, a fatty component is seen within a large aggressive mass and when a hypovascular mass with capsular vessels is seen in angiography.

Computed tomography (CT) and magnetic resonance (MR) findings in two patients with Fahr disease are presented. The CT scan showed extensive high attenuation foci with an almost symmetrical distribution in the dentate nuclei of the cerebellum, pons, basal ganglia and white matter. MR signals of the high attenuation CT foci ranged from hyperintensity to hypointensity. A hypothetical model for CT and MR signals is proposed, based upon the chemical composition of the deposits in Fahr disease. In the authors opinion the term mineralisation is more appropriate for this disease. A pattern of the location and distribution of the mineral ions that participate in this disease is proposed and a functional evaluation of the brain tissue has been estimated. A predictive pattern for the further evolution of the disease is proposed.

We describe the anatomical abnormalities in the hypothalamic-pituitary region revealed by magnetic resonance imaging (MRI) in 10 patients, 8 men and 2 women, affected by idiopathic anterior hypopituitarism (IAH). In all cases contiguous sagittal and coronal T-1 weighted images were obtained. In 9 patients the high-intensity posterior lobe was missing, in almost all patients the pituitary stalk was thin and/or transected, and in 8 a bright T-1 nodule was detected at the infundibular apex, near the tuber cinereum, in the median eminence. None had diabetes insipidus. MRI proves to be very useful in understanding the etiopathogenesis of IAH.

We report the findings on computed tomography (CT) in idiopathic and secondary retroperitoneal fibrosis in 7 patients. In all cases CT showed the fibrotic mass, accurately defining its extent and the involvement of adjacent anatomic structures.

La risonanza magnetica è la tecnica fondamentale nello studio della sclerosi multipla. Lo scopo di questo lavoro è stato il confronto, in termini di sensibilità, tra alcune sequenze di RM attualmente disponibili con l'intento di individuare quella che consente la migliore dimostrazione delle lesioni tipiche della sclerosi multipla.Sono stati studiati 71 pazienti affetti da sclerosi multipla, inclusi nello studio in base ai criteri di Poser. Tutti sono stati sottoposti ad un esame di RM comprendente una sequenza SE pesata in densità protonica (DP) e T2, una sequenza TSE pesata in T2 e una sequenza IR. Il giudizio sulla visibilità delle lesioni demielinizzanti è stato espresso sia in termini soggettivi che in modo oggettivo.Dalla valutazione soggettiva è emerso che, in generale, la visibilità delle placche è risultata soddisfacente nella maggior parte dei casi, con punteggi particolarmente elevati a livello della sostanza bianca periventricolare, mentre punteggi più bassi sono stati attribuiti alle lesioni del cervelletto e del tronco encefalico. Prendendo in considerazione i punteggi attribuiti alle diverse lesioni in relazione al tipo di sequenza impiegata, nel complesso quella migliore è risultata la SE pesata in T2. Dalla valutazione oggettiva invece la sequenza con maggiore contrasto intrinseco è risultata essere la TSE pesata in T2 con una eccezione per quanto concerne il contrasto tra placca e liquor dove la sequenza più affidabile è risultata essere la DP. Dalla valutazione oggettiva emerge dunque un risultato in apparente contraddizione con quello della valutazione soggettiva. Per conciliare risultati così diversi bisogna ipotizzare che il contrasto intrinseco delle immagini non sia il fattore principale che determina l'adeguata visibilità delle lesioni demielinizzanti. Ad esempio, nelle sequenze TSE pesate in T2 alcuni fattori riducono la visibilità delle stesse.In conclusione, dalla nostra esperienza emerge che la sequenza che consente la migliore dimostrazione delle lesioni della sclerosi multipla è la SE pesata in DP e T2, che permette la valutazione di più parametri tissutali in un'unica acquisizione oltre ad essere dotata di un contrasto intrinseco soddisfacente.

Wernicke's encephalopathy is an uncommon disorder caused by a thiamine deficiency which is clinically characterized by the triad of ophthalmoplegia, ataxia and disturbances of consciousness, each finding being variably present. The disease is caused by malnutrition or malabsorption, and is often associated with prolonged alcohol intake, neoplasm and extensive inflammatory processes of the digestive tract and parenteral hyperalimentation-induced gastrointestinal mucosal atrophy. Clinical diagnosis can be elusive and MRI may be the only imaging technique able to detect the cerebral lesions, whose type and distribution are characteristic of the Wernicke's encephalopathy, whereas CT is positive only in exceptional cases. We report a case of a 56-year-old woman who developed a Wernicke's encephalopathy 1 month after a colonic resection with signal intensity changes located in the mammillary bodies and in the medial thalamic nuclei.

Abstract.: The aims of this study were (a) to compare the MR appearance of normal articular cartilage in ex vivo MR imaging (MRI) and MR microscopy (MRM) images of disarticulated human femoral heads, (b) to evaluate by MRM the topographic variations in articular cartilage of disarticulated human femoral heads, and subsequently, (c) to compare MRM images with histology. Ten disarticulated femoral heads were examined. Magnetic resonance images were obtained using spin-echo (SE) and gradient-echo (GE) sequences. Microimages were acquired on cartilage–bone cylindrical plugs excised from four regions (superior, inferior, anterior, posterior) of one femoral head, using a modified SE sequence. Both MRI and MRM images were obtained before and after a 90 rotation of the specimen, around the axis perpendicular to the examined cartilage surface. Finally, MRM images were correlated with histology. A trilaminar appearance of articular cartilage was observed with MRI and with a greater detail with MRM. A good correlation between MRI and MRM features was demonstrated. Both MRI and MRM showed a loss of the trilaminar cartilage appearance after specimen rotation, with greater evidence on MRM images. Cartilage excised from the four regions of the femoral head showed a different thickness, being thickest in the samples excised from the superior site. The MRM technique confirms the trilaminar MRI appearance of human articular cartilage, showing good correlation with histology. The loss of the trilaminar appearance of articular cartilage induced by specimen rotation suggests that this feature is partially related to the collagen-fiber orientation within the different layers. The MRM technique also shows topographic variations in thickness of human articular cartilage.

In order to define the sensitivity and specificity of ultrasonography (US) in the diagnosis of hydronephrosis, 125 patients with normal renal function were examined after urography using high-resolution real-time scanning. The overall diagnostic accuracy of US in detecting hydronephrosis was 85.2%, with a specificity of 84.4% and a sensitivity of 89.9%. It is concluded that US may be considered the screening test of choice for the diagnosis of hydronephrosis. However, urography is still required for the evaluation of renal function, site, and nature of the obstruction when US shows a dilated collecting system and in the patient with a normal US but renal colic.

Ultrasonography was used to evaluate 18 proven cases of carcinoma of the gall-bladder and a prospective diagnosis was correctly achieved in 88.8%. The ultrasonographic findings may be classified into primary and associated. The diagnostic role of ultrasonography is considered and a flowchart of further investigations is suggested. The diagnostic limits for early detection are underlined.