Antonio Rotondo

Spontaneous rupture of a hepatic angiomyolipoma: CT findings and literature review

Abstract. Angiomyolipoma is an uncommon lipomatous neoplasm of the liver, usually asymptomatic and identified incidentally. We describe the CT findings of a surgically confirmed case of spontaneously ruptured angiomyolipoma with evidence of internal hemorrhage and hemoperitoneum. The CT features were that of an exophitic, oval, well-defined mass with inhomogeneous attenuation values due to the presence of fat- and soft-tissue densities. A review of the literature identified 49 cases of hepatic angiomyolipoma. Few of these occurred in symptomatic patients and showed intratumoral hemorrhagic foci, but none had a clear rupture with external bleeding. To our knowledge, this is the first reported case with this complication.

Small animal imaging facility: new perspectives for the radiologist

In recent years, new technologies have become available for imaging small animals. The use of animal models in basic and preclinical sciences, for example, offers the possibility of testing diagnostic markers and drugs, which is becoming crucial in the success and timeliness of research and is allowing a more efficient approach in defining study objectives and providing many advantages for both clinical research and the pharmaceutical industry. The use of these instruments offers data that are more predictive of the distribution and efficacy of a compound. The mouse, in particular, has become a key animal model system for studying human disease. It offers the possibility of manipulating its genome and producing accurate models for many human disorders, thus resulting in significant progress in understanding pathologenic mechanisms. In neurobiology, the possibility of simulating neurodegenerative diseases has enabled the development and validation of new treatment strategies based on gene therapy or cell grafting. Noninvasive imaging in small living animal models has gained increasing importance in preclinical research, itself becoming an independent specialty. The aim of this article is to review the characteristics of these systems and illustrate their main applications.RiassuntoNegli ultimi anni si sono rese disponibili nuove apparecchiature per lo studio di piccoli animali. L’utilizzo di modelli sperimentali nelle scienze di base e pre-cliniche consente di verificare test diagnostici e farmaci, divenendo essenziale per il successo e la tempestività della ricerca, offrendo un approccio più efficace nella definizione degli obiettivi da studiare e notevoli vantaggi sia per la ricerca clinica sia per le industrie farmaceutiche. L’utilizzo di tali tecnologie consente di ottenere informazioni più predittive riguardo alla distribuzione o all’efficacia di una molecola. Il topo, in particolare, è un modello animale insostituibile per lo studio delle malattie umane. Esso offre la possibilità di manipolare il suo genoma e di riprodurre accuratamente malattie umane, consentendo progressi significativi nella comprensione dei meccanismi patogenetici. In neurobiologia, la possibilità di ricreare malattie neurodegenerative ha permesso lo sviluppo e la convalida di nuove strategie terapeutiche basate sulla terapia genica o sul trapianto di cellule. L’imaging non invasivo su piccoli animali in vivo ha acquisito un ruolo sempre maggiore nella ricerca pre-clinica fino a divenire un settore autonomo. Scopo di questo contributo è presentare le caratteristiche di queste apparecchiature illustrandone le principali applicazioni.

Seven-Tesla micro-MRI in early detection of acute arterial ischaemia: evolution of findings in an in vivo rat model

Purpose. Acute mesenteric ischaemia (AMI) is a lifethreatening vascular emergency with a high mortality rate. Early diagnosis is the key to reducing its mortality rate and improving the quality of life. Although computed tomography (CT) is still the gold standard for acute intestinal disorders, over the last few years, magnetic resonance imaging (MRI) has become a useful alternative tool. An animal model of AMI was developed in order to study the effectiveness of MRI in early detection of this condition and to observe lesion evolution. Methods. Thirty Sprague Dawley rats were randomly divided into two groups (n=15): in the fi rst group, after laparotomy, the animals underwent ligation of the superior mesenteric artery (SMA), followed by macroscopic monitoring and histological evaluation; in the second, ischaemia was induced by squeezing a loop around the SMA 3 days before evaluation with 7-T micro-MRI. Results. Macroscopically, a refl ex spastic ileus followed by refl ex hypotonic ileus and colour changes in some of the loops were detected. MRI evidenced luminal dilatation with air‐fl uid levels, free intraperitoneal fl uid and bowelwall oedema. Histological analysis confi rmed ischaemia and earlier damage involving the central portion of thePurposAcute mesenteric ischaemia (AMI) is a life-threatening vascular emergency with a high mortality rate. Early diagnosis is the key to reducing its mortality rate and improving the quality of life. Although computed tomography (CT) is still the gold standard for acute intestinal disorders, over the last few years, magnetic resonance imaging (MRI) has become a useful alternative tool. An animal model of AMI was developed in order to study the effectiveness of MRI in early detection of this condition and to observe lesion evolution.MethodsThirty Sprague Dawley rats were randomly divided into two groups (n=15): in the first group, after laparotomy, the animals underwent ligation of the superior mesenteric artery (SMA), followed by macroscopic monitoring and histological evaluation; in the second, ischaemia was induced by squeezing a loop around the SMA 3 days before evaluation with 7-T micro-MRI.ResultsMacroscopically, a refl ex spastic ileus followed by refl ex hypotonic ileus and colour changes in some of the loops were detected. MRI evidenced luminal dilatation with air-fluid levels, free intraperitoneal fluid and bowelwall oedema. Histological analysis confirmed ischaemia and earlier damage involving the central portion of the ileum.ConclusionsThis model shows the correct sequence of events during arterial AMI and demonstrates that MRI can be recommended for early diagnosis of these lesions.RiassuntoObiettivoL’ischemia mesenterica acuta (IMA) rappresenta un’emergenza vascolare ad elevata mortalità. La diagnosi precoce è imprescindibile per migliorare sopravvivenza e qualità di vita dei pazienti. Sebbene attualmente la tomografia computerizzata (TC) rimane la metodica di scelta nelle patologie intestinali acute, negli ultimi anni la risonanza magnetica (RM) si è proposta come valida alternativa. Per valutare l’efficacia della RM nella diagnosi precoce di IMA ed investigare l’evoluzione delle lesioni è stato utilizzato un modello animale di ischemia mesenterica.Materiali e metodiTrenta ratti Sprague-Dawley sono stati divisi casualmente in 2 gruppi (n=15): nel primo, dopo legatura dell’arteria mesenterica superiore (AMS) in laparotomia, le lesioni sono state monitorate macroscopicamente e istopatologicamente; nel secondo, grazie ad un cappio posizionato all’emergenza dell’AMS tre giorni prima, è stata indotta l’ischemia e valutata con micro-RM a 7 T.RisultatiMacroscopicamente si è osservato un ileo rifl esso spastico, transitato poi in ipotono, ed il viraggio cromatico di alcune anse. La RM ha documentato la dilatazione luminale con livelli idro-aerei, liquido libero intraperitoneale ed edema parietale. L’analisi istopatologica ha confermato l’ischemia con danno più precoce a carico dell’ileo centrale.ConclusioniIl modello documenta la corretta sequenza degli eventi dell’ischemia mesenterica arteriosa acuta (IMAA) e dimostra che la RM può essere proposta per la sua diagnosi precoce.

Ultrasonography versus computed tomography in evaluation of the femoral trochlear groove morphology: a pilot study on healthy, young volunteers

The aim of the study was to verify the efficacy of ultrasonography (US) in evaluating the morphology of normal trochlea, especially the sulcus angle and the trochlear depth, in comparison with computed tomography (CT) (gold standard). The knees of 11 asymptomatic volunteers were subjected to US and CT evaluation of the same section planes and the results were compared. For statistical evaluation Spearman’s correlation coefficient analysis was used. A statistically significant correlation was found between the two diagnostic procedures (sulcus angle: r = 0.820; trochlear depth: r = 0.802; Spearman’s correlation coefficient) and the intra-observer variability for the US measurements (sulcus angle: r = 0.966; trochlear depth: r = 0.914; Spearman’s correlation coefficient). The mean value of sulcus angle and trochlear depth was 132 ° and 5.6 mm, respectively, similar to those reported in the literature. We conclude that evaluation by US of both sulcus angle and trochlear depth is as reproducible and sensitive as that performed with CT.

The role of Tc-99m-2-Methoxy-Isobutyl-Isonitrile Single Photon Emission Computed Tomography in visualizing anterior mediastinal tumor and differentiating histologic type of thymoma

OBJECTIVEnTo evaluate the usefulness of (99m)Tc-2-Methoxy-Isobutyl-Isonitrile Single Photon Emission Computed Tomography (MIBI-SPECT) for assessing anterior mediastinal mass, and distinguishing the grade of malignancy of thymic epithelial tumors to offer guidance for decision making.nnnMETHODSnFrom January 2006 to November 2009, 31 consecutive patients with an anterior mediastinal mass at CT were enrolled. All patients underwent (99m)Tc-MIBI-SPECT before invasive diagnostic procedures and/or surgical resection. The uptake of the mediastinal tumor (T) was compared with the normal tissue (N) and the T/N ratio was calculated to define the metabolic activity of the lesions. Patients were divided into six groups according histologic patterns, which were then correlated to the T/N value: benign tumor (BT), lymphoma (LYM), other malignant tumor (OMT), and low-risk thymoma (LRT) including types A, AB, and B1, high-risk thymoma (HRT) including types B2 and B3, and thymic carcinoma (TC).nnnRESULTSnThere were five BT, eight LRT (four = A, two = AB, and two = B1), four HRT (three = B2 and one = B3), four thymic carcinoma, six LYM and four OMT. The T/N value of BT, LRT, HRT, CT, LYM, and OMT was 1.3 ± 0.3, 1.3 ± 0.2, 1.8 ± 0.3, 2.7 ± 0.5, 2.8 ± 0.1, and 2.9 ± 0.2, respectively. The T/N ratio of BT and of LRT was significantly lower than that of HRT, of CT, of LYM, and of OMT (p < 0.05), while there is no significant difference of MIBI uptake between BT and LRT. MIBI uptake in HRT was significantly lower than that in TC, LYM, and OMT (p < 0.05), whereas no significant difference was found between the different types of malignant lesions (TC, LYM, and OMT). Regarding thymoma, the degree of MIBI accumulation significantly increased as the World Health Organization (WHO) classification shifted from type A to type B and to TC. Yet, the T/N value of stages I and II was significantly lower than that of stages III and IV. The size of the lesion and the presence of myasthenia were not correlated with MIBI uptake.nnnCONCLUSIONn(99m)Tc-MIBI-SPECT seems to be useful in the evaluation of malignancy in anterior mediastinal mass, and is significantly correlated with the WHO classification and the Masaoka stage. Thus, this technique may add further information to morphological studies for decision making.

Renal oncocytoma: misleading diagnosis of benignancy by using angular interface sign at MR imaging.

We have read the letter from Drs Lacout and Marcy regarding our recent Radiology article ( 1 ) and hereby provide our reply. We investigated all nodules that underwent US-guided FNAB, regardless of size and gray-scale US features, not just nodules with at least one suspicious gray-scale feature. Suspicious gray-scale US features that were widely used were determined on the basis of all the nodules studied, not a subgroup. Suspicious US features were investigated for all nodules to evaluate the association between the prediction of malignancy and US features. If the study were performed in a subgroup, the power Doppler US features would not be factors for differentiating benign and malignancy; they would simply be predominant features in the subgroups. The power Doppler features were investigated in the hypoechoic subgroup in our study, but the diagnostic performance was also low. In terms of the qualitative analysis, it should be performed after intranodular vascularity is validated as a factor that predicts malignancy. Moreover, there were no objective criteria for “the rich intralesional vascularity with anarchical structure and winding vessel” or “nodules Renal Oncocytoma: Misleading Diagnosis of Benignancy by Using Angular Interface Sign at MR Imaging

Sonography of chondral print on humeral head

ObjectiveThe aim of this study is to determine the diagnostic accuracy of sonography in order to identify the chondral print on the humeral head.Materials and methodsIn total, 44 patients who had already been candidates for arthroscopic surgery were prospectively studied with ultrasound to assess the presence of humeral subchondral erosion at the level of the biceps pulley; no patient had undergone previous surgery or radiographic calcification of rotator cuff tendons. Using arthroscopy as the reference standard the sensitivity, specificity, positive predictive, negative predictive and diagnostic accuracy values were calculated.ResultsOf the 44 patients, arthroscopy showed the humeral chondral print in 30 patients. Of the 30 arthroscopy proven humeral chondral prints, ultrasound identified 28 subchondral erosions at the same level, with two false negatives. One of the 14 patients without arthroscopic humeral chondral print was positive for subchondral erosion at ultrasound. The sensitivity, specificity, positive predictive, negative predictive, and diagnostic accuracy values of ultrasound were respectively of 93, 93, 96, 87 and 93xa0%.ConclusionUltrasound has a good diagnostic accuracy in identifying the chondral print sign.

Role of percutaneous transcatheter embolization (PTE) in the treatment of spontaneous bleeding associated with anticoagulant therapy

AbstractPurposeTon evaluate safety and clinical efficacy of percutaneous transcatheter embolization (PTE) in the treatment of spontaneous bleedings (SBs) in patients submitted to chronic anticoagulation therapy.Materials and methodsFrom January 2007 to December 2012, 20 patients (mean age 75.8xa0years, range 68–91xa0years) with 23 SBs were retrospectively evaluated. Active bleeding was documented by contrast enhanced-multidetector row computed tomography (CE-MDCT). PTE was performed using different embolic agents. Technical success (TS), clinical success (CS), late success (LS) and mortality rate (M) related to the angiographic procedure and complications were evaluated.ResultsCE-MDCT and digital subtraction angiography (DSA) identified active bleeding sites in 18 cases (18/20). In two cases (2/20) DSA did not confirm the arterial bleeding diagnosed on CE-MDCT. Twenty-three sessions of PTE were performed. TS, CS, LS and M were, respectively, 100, 85, 15 and 0xa0%. No major complications were observed.ConclusionsPTE could be considered a safe and effective “first line” approach to treat SB associated with anticoagulation therapy.

Segmental pulmonary arteries: two-dimensional and three-dimensional time-of-flight magnetic resonance angiography.

The authors compared two-dimensional (2D) and three-dimensional (3D) time-of-flight (TOF) magnetic resonance angiography in ten healthy volunteers to establish which of two techniques is more effective in representing the pulmonary segmental arteries. No respiratory trigger or electrocardiogram gating was used. Pre-saturation pulses were used to eliminate venous flow. Images acquired in the sagittal planes were processed using maximum intensity projection. A total of 200 segmental arteries were evaluated with each technique by three observers (M.S., C.S., A.R.) in terms of vessel visibility. There was no significant difference among the observers interpretations (p < 0.05). On average, 2D fast, low-angle shot breath-hold TOF sequences showed 136.1 of 200 (68%) segmental arteries, 74.1 of 100 in the right lung and 62 of 100 in the left lung. Three-dimensional fast imaging with steady state precession showed 171.6 of 200 (85.8%) segmental arteries, 94 of 100 in the left lung and 77.6 of 100 in the left lung. Three-dimensional imaging appeared to be better than 2D MRA for demonstration of segmental pulmonary arteries.

SPLIT-BOLUS SINGLE-PASS MULTIDETECTOR-ROW CT PROTOCOL FOR DIAGNOSIS OF ACUTE PULMONARY EMBOLISM

Background: Currently computed tomography pulmonary angiography (CTPA) has become a widely accepted clinical tool in the diagnosis of acute pulmonary embolism (PE). Objectives: To report split-bolus single-pass 64-multidetector-row CT (MDCT) protocol for diagnosis of PE. Patients and Methods: MDCT split-bolus results in 40 patients suspicious of PE were analyzed in terms of image quality of target pulmonary vessels (TPVs) and occurrence and severity of flow-related artifact, flow-related artifact, false filling defect of the pulmonary veins and beam hardening streak artifacts. Dose radiation to patients was calculated. Results: MDCT split-bolus protocol allowed diagnostic images of high quality in all cases. Diagnosis of PE was obtained in 22 of 40 patients. Mean attenuation for target vessels was higher than 250 HU all cases: 361 ± 98 HU in pulmonary artery trunk (PAT); 339 ± 93 HU in right pulmonary artery (RPA); 334 ± 100 HU in left pulmonary artery (LPA). Adequate enhancement was obtained in the right atrium (RA):292 ± 83 HU; right pulmonary vein (RPV): 302 ± 91 HU, and left pulmonary vein (LPV): 291 ± 83 HU. The flow related artifacts and the beam hardening streak artifacts have been detected respectively in 4 and 25 patients. No false filling defect of the pulmonary veins was revealed. Conclusion: MDCT split-bolus technique by simultaneous opacification of pulmonary arteries and veins represents an accurate technique for diagnosis of acute PE, removes the false filling defects of the pulmonary veins, and reduces flow related artifacts.