Luca Salvolini

Performance of imaging modalities in diagnosis of liver metastases from colorectal cancer: A systematic review and meta-analysis

Surgery of liver metastases can be effective, and the appropriate selection of surgical candidates relies first on imaging. Different techniques are available, but information on their relative performance is unclear. The aim of this overview is to assess the imaging modality performance in the diagnosis of colorectal cancer (CRC) liver metastases. MEDLINE and EMBASE were searched for articles published from January 2000 to August 2008. Eligible trials had to be conducted on patients with diagnosis/suspicion of CRC liver metastases, comparing more than two modalities among MRI, computed tomography (CT), positron emission tomography using fluoro‐18‐deoxyglucose (FDG‐PET), ultrasonography (US). Pooled estimates of sensitivity, specificity were calculated and pair‐wise comparisons were performed. Of 6030 screened articles, 25 were eligible. Sensitivity and specificity on a per‐patient basis for US, CT, MRI, and FDG‐PET were 63.0% and 97.6%, 74.8% and 95.6%, 81.1% and 97.2, and 93.8% and 98.7%, respectively. On a per‐lesion basis, sensitivity was 86.3%, 82.6%, 86.3%, and 86.0%, respectively. Specificity was reported in few studies. MRI showed a better sensitivity than CT in per‐patient (odds ratio [OR]: 0.69; 95% confidence interval [CI]: 0.47–0.99; P = 0.05) and in per‐lesion analysis (OR: 0.66; 95% CI: 0.55–0.80; P < 0.0001). In per‐lesion analysis, the difference was higher when liver‐specific contrast agents were administered. Available evidence supports the MRI use for the detection of CRC liver metastases. J. Magn. Reson. Imaging 2010;31:19–31.

Magnetic resonance cholangiopancreatography in primary sclerosing cholangitis in children.

Background: Primary sclerosing cholangitis (PSC) is a chronic cholestatic syndrome of unknown aetiology. Diagnosis is based on clinical and laboratory data in conjunction with imaging of the biliary tree using endoscopic retrograde cholangiopancreatography (ERCP). Objective: To evaluate the clinical usefulness of MR cholangiopancreatography (MRCP) in the diagnosis of PSC in children. Materials and methods: Twenty-one children with clinical and laboratory suspicion of PSC were enrolled. MRCP was performed using a superconductive system with a phased-array coil. Rapid acquisition with relaxation enhancement (RARE) T2-weighted and half-Fourier single-shot turbo-spin-echo (HASTE) sequences were used. The distribution and extent of biliary tree changes were evaluated and classified according to Majoies classification. A comparison between MRCP and ERCP was performed blind in all cases to evaluate the usefulness of MRI. Results: In 13 cases (62%), MRCP showed abnormalities of the biliary tree which were considered positive for PSC, while in 8 cases there were no signs of PSC. Both MRCP and ERCP correctly identified changes in 13 cases and excluded abnormalities in 5. MRCP had a sensitivity of 81%, specificity of 100%, negative predictive value of 62%, positive predictive value of 100% and an accuracy of 85%. Conclusions: MRCP can be proposed as the preliminary non-invasive imaging modality for the diagnosis of PSC in children.

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

PurposeWe 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 methodsA 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.ResultsIn 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.ConclusionsHepatobiliary-specific contrast agents allow for accurate and extensive study of biliary tract alterations, especially in assessing postsurgical complications.RiassuntoObiettivoScopo del nostro lavoro è valutare l’utilità della colangio-risonanza magnetica (RM) con mezzo di contrasto epatospecifico (CE-MRC) nello studio delle complicanze post-chirurgia epatica.Materiali e metodiSono stati valutati 142 pazienti sottoposti ad intervento di chirurgia epatica con sospette complicanze biliari con colangio-pancreato-RM (MRCP) e sequenze post-contrasto con somministrazione di gadolinio-acido etossi-benzil-dietilen-triamino-pentaacetico (Gd-EOB-DTPA). Due radiologi con decennale esperienza specifica hanno valutato in cieco le immagini ottenute dalla MRCP e quelle della CE-MRC con analisi semiquantitativa dei reperti.RisultatiIn tutti i casi si è ottenuta adeguata visualizzazione biliare dopo somministrazione di mezzo di contrasto (MdC). ventidue dei 142 casi esaminati hanno mostrato complicanze biliari post-chirurgiche. La MRCP ha rilevato il 64% delle lesioni, ma nel 36% dei casi ha permesso solo di sospettare un’alterazione, senza consentire una definizione dirimente. La CE-MRC ha consentito una diagnosi certa nel 100% dei casi.ConclusioniL’uso di MdC ad escrezione epatobiliare consente uno studio accurato e panoramico delle alterazioni delle vie biliari, specie nelle complicanze postchirurgiche.

Magnetic resonance imaging (MRI) artefacts in hip prostheses: a comparison of different prosthetic compositions

PurposeThe purpose of the study was to compare the artefacts produced by different hip prostheses on magnetic resonance imaging (MRI).Materials and methodsAn identical MRI protocol was used to perform a quali-quantitative in vitro evaluation of artefacts caused by different hip prosthetic materials at different field strengths: prosthesis number 1, composed of cobalt–chrome–molybdenum (head and stem); prosthesis number 2, composed of ceramic (head) and titanium (stem); prosthesis number 3, composed of cobalt–chrome (head) and titanium (stem). All prostheses were imaged with both a clinical 1 Tesla (T) (Signa Horizon, General Electrics) and 1.5 T (Achieva, Philips) MRI system, using spin echo (SE) and gradient echo (GRE) sequences: sagittal T1 SE, coronal T2 fast SE (FSE), axial T1 SE, axial T2 FSE, sagittal T2 GRE, axial T2* GRE, coronal T1 GRE, axial T1 GRE. The artefacts produced by each prosthesis were assessed in each sequence at the different field strengths, by measuring the two longest diameters of the artefact in each section and sequence and comparing them to the actual diameters so as to obtain a ratio expressing the effective degree of artefact.ResultsCobalt–chrome produced the largest artefacts both in SE (1.73 at 1 T and 2.37 at 1.5 T) and GRE sequences (2.8 at 1 T and 3.06 at 1.5 T) followed by titanium (SE, 1.6 at 1 T, 2.13 at 1.5 T; GRE, 2 at 1 T, 2.94 at 1.5 T) and cobalt–chrome–molybdenum (SE, 1.51 at 1 T, 1.67 at 1.5 T; GRE, 2.13 at 1 T and 2.48 at 1.5 T); ceramic produced the smallest artefacts in all sequences (SE, 1.0 at 1 T and 1.18 at 1.5 T; GRE, 1.3 at 1 T and 1.22 at 1.5T). Increasing the magnetic field strength, titanium showed the greatest variations in artefact size, and ceramic the smallest ones.ConclusionsThe composition of prosthetic implants is decisive in determining the quality of MR imaging.

Chest radiography in intensive care: an irreplaceable survey?

PurposeThis study evaluated the impact and value of bedside chest X-ray in intensive care units.Materials and methodsThis observational study considered the bedside chest X-rays performed on 258 consecutive patients (160 men, 98 women; mean age, 58 years) admitted to intensive care units. Stratification of patients according to the reason for hospitalisation and analysis of the reasons for chest X-ray examinations were performed to assess the diagnostic efficacy (DE).ResultsDE for chest X-rays was 84.5%, with 15.5% of tests remaining unchanged over time. Patient stratification by disease indicated that the DE was 85.27% in transplant, 90.79% in postoperative care after general surgery, 83.89% in respiratory failure, 82.42% in polytrauma, 90.54% in postoperative care after neurosurgery, 86.6% in postoperative care after vascular surgery, 83.3% in neurological conditions and 93.4% in other diseases.ConclusionsChest X-rays performed at the bedside are the most widely used imaging method in the follow-up of critically ill patients. DE is approximately 84.5%. Radiologists should maintain familiarity with the interpretation of this examination.RiassuntoObiettivoIl presente lavoro si propone la valutazione dell’incidenza e della validità dell’utilizzo dell’Rx torace a letto nei reparti di terapia intensiva.Materiali e metodiSi tratta di uno studio osservazionale sugli Rx torace a letto effettuati su 258 pazienti consecutivi (160 maschi/98 femmine; età media 58 anni) ricoverati presso i reparti di terapia intensiva. è stata effettuata una stratificazione dei pazienti in base al motivo del ricovero ed analisi sui motivi che hanno portato agli esami Rx torace al fine di valutarne l’efficacia diagnostica (ED).RisultatiL’ED è risultata dell’84,5%. Il 15,5% degli esami eseguiti è risultato invariato; stratificando i pazienti per patologia si è visto che l’ED per i pazienti sottoposti a trapianto è stata dell’85,27%, nei post-operatori (PO) di chirurgia generale 90,79%, negli affetti da insufficienza respiratoria (IR) 83,89%, nei politrauma (PT) 82,42%, nei PO di neurochirurgia 90,54 %, nei PO di chirurgia vascolare 86,6%, negli affetti da patologie neurologiche 83,3% ed in quelli ricoverati per altre patologie 93,4%.ConclusioniIl radiogramma del torace eseguito a letto è la metodica di imaging maggiormente utilizzata nel follow-up dei pazienti critici con una ED dell’84,5% circa. Il radiologo deve mantenere una grande dimestichezza nell’interpretazione di questo esame.

Studio con mezzo di contrasto: perfusione e delayed enhancement

Nella cardiopatia ischemica, il danno finale miocardico evolve in modo plurifattoriale, attraverso una cascata di eventi in cui ad ogni livello patologico (preclinico, danno reversibile, lesione stabilizzata) corrisponde l’applicazione di uno o piu test diagnostici elettrofisiologici, clinico-laboratoristici e di imaging [1]. Nell’ambito della diagnostica per immagini, mentre la tomografia computerizzata (TC) si e andata affermando nello studio del versante coronarico, la risonanza magnetica (RM) ha consolidato la sua posizione nello studio di tutta la gamma delle ripercussioni cardiache gia a partire dal piu precoce evento della cascata ischemica, costituito dall’iniziale compromissione perfusionale sub-endocardica anche latente, proseguendo nella dimostrazione del deficit funzionale, fino alle lesioni stabilizzate ischemiche, dapprima reversibili, e quindi alla necrosi irreversibile [2, 3, 4]. Negli ultimi anni lo sviluppo tecnologico dell’hardware (magneti ad alta omogeneita e gradienti piu potenti e veloci) e del software (sequenze ibride ed imaging parallelo) hanno consentito un imaging cardiaco affidabile allo stato dell’arte, caratterizzato da un’elevata risoluzione temporale, spaziale e di contrasto.

Tromboembolia polmonare con embolia paradossa

1. L’embolizzazione arteriosa sistemica associata alla trombosi venosa profonda con embolia polmonare. 2. Pervieta del forame ovale. 3. Ecocardiografia. 4. Terapia anticoagulante/trombolitica, eventualmente filtro cavale e chiusura del forame ovale.

Ematoma intramurale dell’aorta toracica complicato

1. Lo stravaso ematico acuto tra gli strati di parete aortica. 2. Si, e indispensabile ai fini di una corretta diagnosi differenziale. 3. Tipo A. 4. La presenza di emopericardio, oltre che di soffusione peri-avventiziale e del versamento pleurico.

Dissezione aortica di Tipo A secondo Stanford con malperfusione coronarica e carotidea

1. Dissezione aortica di Tipo A secondo Stanford. 2. Interessamento da parte della dissezione della carotide comune destra. 3. Ipoperfusione della coronaria sinistra ad origine dal vero lume ipoperfuso. 4. Trattamento chirurgico.