Lorenzo Cereser

Post-cholecystectomy syndrome: spectrum of biliary findings at magnetic resonance cholangiopancreatography

Post-cholecystectomy syndrome (PCS) is defined as a complex of heterogeneous symptoms, consisting of upper abdominal pain and dyspepsia, which recur and/or persist after cholecystectomy. Nevertheless, this term is inaccurate, as it encompasses biliary and non-biliary disorders, possibly unrelated to cholecystectomy. Biliary manifestations of PCS may occur early in the post-operative period, usually because of incomplete surgery (retained calculi in the cystic duct remnant or in the common bile duct) or operative complications, such as bile duct injury and/or bile leakage. A later onset is commonly caused by inflammatory scarring strictures involving the sphincter of Oddi or the common bile duct, recurrent calculi or biliary dyskinesia. The traditional imaging approach for PCS has involved ultrasound and/or CT followed by direct cholangiography, whereas manometry of the sphincter of Oddi and biliary scintigraphy have been reserved for cases of biliary dyskinesia. Because of its capability to provide non-invasive high-quality visualisation of the biliary tract, magnetic resonance cholangiopancreatography (MRCP) has been advocated as a reliable imaging tool for assessing patients with suspected PCS and for guiding management decisions. This paper illustrates the rationale for using MRCP, together with the main MRCP biliary findings and diagnostic pitfalls.

Comparison of Portal Venous and Delayed Phases of Gadolinium-Enhanced Magnetic Resonance Imaging Study of Cirrhotic Liver for the Detection of Contrast Washout of Hypervascular Hepatocellular Carcinoma

Objective: To retrospectively compare portal venous phase (PVP) and delayed phase (DP) for the detection of tumor washout at gadobenate dimeglumine-enhanced liver magnetic resonance imaging (MRI) in cirrhotic patients with hypervascular hepatocellular carcinoma (HCC). Methods: Thirty-three patients with 55 HCCs underwent 1.5-T MRI by means of fat-suppressed T1-weighted sequence obtained before and after gadobenate dimeglumine administration, during early and late arterial phases, PVP (70 seconds), and DP (180 seconds). Detection rates of contrast washout of hypervascular HCCs and tumor-to-liver contrast on PVP and DP were measured and compared. Results: Among 54 hypervascular HCCs, washout was present in 24 (44%) of 54 tumors on PVP and in 44 (82%) of 54 on DP (P < 0.001). In 20 (37%) of 54 tumors, washout was deemed present only on DP. Delayed phase images yielded significantly higher mean tumor-to-liver contrast absolute values compared with PVP images (−24.5 [56.1] vs −9.3 [52.6], P = 0.001). Conclusions: Delayed phase is superior to PVP for the washout detection of hypervascular HCC at gadobenate dimeglumine-enhanced MRI of cirrhotic liver.

Impact of clinical data on chest radiography sensitivity in detecting pulmonary abnormalities in immunocompromised patients with suspected pneumonia

PurposeChest radiography (CXR) of immunocompromised patients has low sensitivity in the early evaluation of pulmonary abnormalities suspected to be infectious. The purpose of the study was to evaluate whether the knowledge of clinical data improves the diagnostic sensitivity of CXR in the particular setting of immunocompromised patients after hematopoietic stem cell transplantation (HSCT).Materials and methodsSixty-four CXRs of immunocompromised patients with clinically suspected pneumonia were retrospectively and independently evaluated by two radiologists to assess the presence of radiological signs of pneumonia, before (first reading) and after (second reading) the knowledge of clinical data. A chest computed tomography (CT) performed within 3 days was assumed as the standard of reference. For each reading, sensitivity of both radiologists was calculated.ResultsReaders showed a sensitivity of 39% and 58.5% for the first reading, and 43.9% and 41.5% for the second reading, respectively. For both readers, these values were not significantly different from those obtained at first reading (McNemar’s test, p>0.05). Interobserver agreement at second reading was fair (Cohen test, k=0.33).ConclusionsThe sensitivity of CXR is too low to consider it a stand-alone technique for the evaluation of immunocompromised patients after HSCT with suspected pneumonia, even if the radiologist knows detailed clinical data. For these patients, an early chest CT evaluation is therefore recommended.RiassuntoObiettivoLa radiografia (Rx) del torace ha bassa sensibilità nell’individuazione precoce di infiltrati polmonari di sospetta natura infettiva nei pazienti immunocompromessi. Scopo dello studio è stato valutare se la conoscenza della clinica del paziente possa migliorarne la sensibilità diagnostica nel particolare contesto dei pazienti immunodepressi per trapianto di cellule staminali.Materiali e metodiDue medici radiologi hanno valutato retrospettivamente 64 radiografie del torace di pazienti immunocompromessi con sospetto clinico di polmonite per l’eventuale presenza di reperti compatibili con polmonite, senza conoscere (prima lettura) e conoscendone (seconda lettura) la storia clinica. Il gold standard utilizzato è stato una tomografia computerizzata (TC) del torace eseguita entro tre giorni dall’Rx. Per ciascuna lettura, è stata calcolata la sensibilità dei due lettori.RisultatiLa sensibilità dei due radiologi è stata rispettivamente del 39% e del 58,5% nella prima lettura e del 43,9% e del 41,5% nella seconda lettura. Confrontando i dati ottenuti nella prima e nella seconda lettura è emerso come, per entrambi i lettori, la differenza non fosse statisticamente significativa (test di McNemar, p>0,05). Nella seconda lettura, la correlazione inter-osservatore è stata discreta (k di Cohen 0,33).ConclusioniAnche alla luce di dettagliate informazioni cliniche, la sensibilità della radiografia del torace rimane troppo bassa per considerare tale indagine sufficiente nella valutazione dei pazienti immunocompromessi, in seguito a trapianto di cellule staminali emopoietiche, con sospetta polmonite. In tali pazienti, è dunque consigliabile un precoce utilizzo della TC torace.

Accuracy of visual analysis vs. apparent diffusion coefficient quantification in differentiating solid benign and malignant focal liver lesions with diffusion-weighted imaging.

PurposeThe authors compared the accuracy of diffusion-weighted imaging (DWI) visual analysis (VA) vs. apparent diffusion coefficient quantification (ADC-Q) in assessing malignancy of solid focal liver lesions (FLLs).Materials and methodsUsing a 1.5-T system, two radiologists retrospectively assessed as benign or malignant 50 solid FLLs: (a) by VA of signal intensity on DWI images at b=800 s/mm2 and ADC map; (b) by quantifying lesion ADC. Reference standard included histology or follow-up confirmation of diagnosis by a consensus panel. Receiver operating characteristic (ROC) curve analysis was performed.Results Because of 20 false-negative hepatocellular carcinomas, VA showed lower accuracy than ADC-Q (52.0% vs. 68.0%). However, stratified accuracy for metastases was higher with VA (75.0 vs. 66%). ADC and signal features of malignant and benign FLLs were found to largely overlapConclusionsVA performed worse than ADC-Q for hepatocellular carcinoma and better for metastases. Overall, the accuracy of both methods was limited because of the overlap in visual appearance and ADC values between solid benign and malignant FLLs.RiassuntoObiettivoUsando l’imaging pesato in diffusione (DWI), abbiamo confrontato l’accuratezza di analisi visiva (AV) e quantificazione del coefficiente di diffusione apparente (Q-ADC) nella diagnosi di malignità delle lesioni focali epatiche (LFE).Materiali e metodi Su un sistema ad 1,5 T, due radiologi hanno retrospettivamente caratterizzato come benigne o maligne 50 LFE solide: (a) attraverso la AV dell’intensità di segnale nelle immagini DWI acquisite a b=800 s/mm 2 e nella mappa ADC; (b) quantificando l’ADC delle lesioni. La diagnosi finale si è basata sui risultati dell’istologia o sulla conferma al follow-up della diagnosi ottenuta in consenso da due radiologi esperti. La analisi statistica è stata incentrata su una analisi receiver operating characteristic (ROC)Risultati A causa di 20 epatocarcinomi risultati falsinegativi, la AV ha dimostrato minore accuratezza rispetto alla Q-ADC (52,0% vs. 68,0%). Tuttavia, la stratificazione dell’analisi ha evidenziato che l’accuratezza nel caso delle metastasi era maggiore per la AV (75,0% vs. 66,7%). Gli ADC e le caratteristiche di segnale delle LFE maligne e benigne si sono dimostrati ampiamente sovrapponibiliConclusioniRispetto alla Q-ADC, la AV è risultata meno accurata nella diagnosi di malignità nel caso dell’epatocarcinoma, e più accurata nel caso delle metastasi. Complessivamente, l’accuratezza di entrambi i metodi è risultata limitata a causa della sovrapposizione delle caratteristiche di segnale e di ADC fra lesioni solide benigne e maligne.

Magnetic resonance cholangiography in the assessment and management of biliary complications after OLT

Despite advances in patient and graft management, biliary complications (BC) still represent a challenge both in the early and delayed period after orthotopic liver transplantation (OLT). Because of unspecific clinical presentation, imaging is often mandatory in order to diagnose BC. Among imaging modalities, magnetic resonance cholangiography (MRC) has gained widespread acceptance as a tool to represent the reconstructed biliary tree noninvasively, using both the conventional technique (based on heavily T2-weighted sequences) and contrast-enhanced MRC (based on the acquisition of T1-weighted sequences after the administration of hepatobiliary contrast agents). On this basis, MRC is generally indicated to: (1) avoid unnecessary procedures of direct cholangiography in patients with a negative examination and/or identify alternative complications; and (2) provide a road map for interventional procedures or surgery. As illustrated in the review, MRC is accurate in the diagnosis of different types of biliary complications, including anastomotic strictures, non-anastomotic strictures, leakage and stones.

Impact of magnetic resonance cholangiography in managing liver-transplanted patients: preliminary results of a clinical decision-making study

PurposeThis study was performed to assess the role of magnetic resonance cholangiography (MRC) in the clinical decision-making process of referring physicians when managing liver-transplanted patients.Materials and methodsOver a 6-month period, 21 liver-transplanted patients with a suspected biliary complication were referred for MRC. Referring physicians were asked to prospectively state, before and after MRC, the leading diagnosis; the level of confidence (on a 0–100% scale); the most appropriate diagnostic/therapeutic plan. Data analysis assessed was the diagnostic yield of MRC; the proportion of change in the leading diagnosis; the therapeutic efficacy (i.e. proportion of change in the initial diagnostic/therapeutic plan); the diagnostic thinking efficacy (i.e., gain in diagnostic confidence). Statistical significance was assessed with the Mann-Whitney U test. MRC accuracy was also calculated.ResultsData analysis showed a diagnostic yield of 85.7%; a proportion of change in leading diagnosis of 19.0%; a therapeutic efficacy of 42.8%; a diagnostic thinking efficacy for concordant and discordant leading diagnoses of 18.8% and 78.7%, respectively (p<0.01). MRC accuracy was 92.3%.ConclusionsMRC significantly increased the diagnostic confidence, irrespective of the concordance between pre- and posttest diagnoses. Moreover, MRC determined a change in patient management in a significant proportion of cases, leading to clinical benefits.RiassuntoObiettivoScopo del presente lavoro è stato definire il ruolo della colangiografia in risonanza magnetica (CRM) nei pazienti trapiantati di fegato, nel processo di clinical decision-making dei clinici di riferimento.Materiali e metodiIn un periodo di sei mesi, 21 pazienti trapiantati di fegato con sospette complicanze biliari sono stati inviati alla CRM. In modo prospettico, ai clinici di riferimento è stato richiesto di indicare, prima e dopo la CRM: la diagnosi presuntiva; il livello di confidenza (su scala 0%–100%); il piano diagnostico/terapeutico più appropriato. L’analisi dei dati ha valutato: la resa diagnostica; la proporzione di diagnosi presuntive modificate; l’efficacia terapeutica (vale a dire, proporzione di piani diagnostico/terapeutici modificati); l’efficacia diagnostica presuntiva (vale a dire, guadagno in confidenza diagnostica). La significatività statistica è stata valutata con test U di Mann-Whitney. È stata inoltre calcolata l’accuratezza della CRM.RisultatiL’analisi dei dati ha dimostrato: una resa diagnostica del 85,7%; una proporzione di diagnosi presuntive modificate del 19,0%; un’efficacia terapeutica del 42,8%; un’efficacia diagnostica presuntiva rispettivamente pari a 18,8% e 78,7% per diagnosi presuntive concordanti e discordanti (p<0,01). L’accuratezza della CRM è stata del 92,3%.ConclusioniLa CRM ha incrementato significativamente la confidenza diagnostica, indipendentemente dalla concordanza tra la diagnosi pre- e post-test. La CRM ha inoltre determinato una modifica nella gestione dei pazienti in una proporzione significativa di casi, portando ad un beneficio clinico grazie alla sua elevata accuratezza.

Chest multidetector computed tomography (MDCT) in patients with suspected acute pulmonary embolism: diagnostic yield and proportion of other clinically relevant findings

PurposeThe authors evaluated the diagnostic yield of chest multidetector computed tomography (MDCT) in acute pulmonary embolism (PE) and the proportion of other clinically relevant findings in a large cohort of consecutive inpatients and patients referred from the emergency department (outpatients).Materials and methodsA total of 327 radiological reports of chest MDCT scans performed for suspected acute PE in 327 patients (158 men, 169 women; mean age 69 years, standard deviation 17.33 years; 233 inpatients, 94 outpatients) were retrospectively evaluated and classified into four categories: 1, positive for PE; 2, negative for PE but positive for other findings requiring specific and immediate intervention; 3, completely negative or positive for findings with a potential for significant morbidity requiring specific action on follow-up; 4, indeterminate. The distribution of findings by categories among the entire population and inpatients and outpatients separately was calculated (chi-square test, α=0.05).ResultsIn the entire population, the diagnostic yield (i.e. proportion of cases classified as category 1) was 20.2% (66/327). Proportions of cases classified as categories 2, 3 and 4 were 27.5% (90/327), 44.3% (145/327) and 7.9% (26/327), respectively. No statistically significant difference was found between inpatients and outpatients (p=0.193).ConclusionsIn patients with suspected acute PE, chest MDCT provides evidence of conditions requiring immediate and specific intervention (i.e. categories 1 and 2) in nearly 50% of cases, without differences between inpatients and outpatients.RiassuntoObiettivoScopo del nostro lavoro è stato valutare la resa diagnostica della tomografia computerizzata multidetettore (TCMD) del torace nell’embolia polmonare acuta (EP) e la proporzione di altri reperti clinicamente rilevanti in un’ampia coorte di pazienti consecutivi, sia ricoverati che provenienti dal Pronto Soccorso (PS).Materiali e metodiSono stati retrospettivamente considerati 327 referti radiologici di TCMD del torace eseguite per sospetta EP acuta in 327 pazienti (158 M, 169 F; età media, 69 anni, deviazione standard [DS] 17,33 anni; 233 ricoverati, 94 provenienti dal PS). Gli esami sono stati classificati in quattro categorie: 1. positivi per EP; 2. negativi per EP, ma positivi per altri reperti richiedenti intervento specifico ed immediato; 3. negativi del tutto o positivi per reperti con potenziale significato di morbilità richiedenti specifico intervento al follow-up; 4. indeterminati. È stata calcolata la distribuzione dei reperti in categorie nell’intera popolazione e, separatamente, nei pazienti ricoverati e nei pazienti provenienti dal PS (test Chi-quadrato, α=0,05).RisultatiNell’intera popolazione, la resa diagnostica (vale a dire proporzione di casi classificati in categoria 1) è stata del 20,2% (66/327). Le proporzioni di casi classificati in categoria 2, 3 e 4 sono state del 27,5% (90/327), 44,3% (145/327) e 7,9% (26/327), rispettivamente. Non sono state rilevate differenze statisticamente significative tra i pazienti ricoverati e quelli provenienti dal PS (p=0,193).ConclusioniNei pazienti con sospetta EP acuta, la TCMD del torace evidenzia condizioni richiedenti un intervento specifico ed immediato (vale a dire, categorie 1 e 2) in quasi il 50% dei casi, senza differenze tra i pazienti ricoverati e quelli provenienti dal PS.

Can multiparametric MRI replace Roach equations in staging prostate cancer before external beam radiation therapy

PURPOSE To investigate the agreement between Roach equations (RE) and multiparametric magnetic resonance imaging (mpMRI) in assessing the T-stage of prostate cancer (PCa). MATERIALS AND METHODS Seventy-three patients with biopsy-proven PCa and previous RE assessment prospectively underwent mpMRI on a 3.0T magnet before external beam radiation therapy (EBRT). Using Cohens kappa statistic, we assessed the agreement between RE and mpMRI in defining the T-stage (≥T3 vs.T≤2) and risk category according to the National comprehensive cancer network criteria (≤intermediate vs. ≥high). We also calculated sensitivity and specificity for ≥T3 stage in an additional group of thirty-seven patients with post-prostatectomy histological examination (mpMRI validation group). RESULTS The agreement between RE and mpMRI in assessing the T stage and risk category was moderate (k=0.53 and 0.56, respectively). mpMRI changed the T stage and risk category in 21.9% (95%C.I. 13.4-33-4) and 20.5% (95%C.I. 12.3-31.9), respectively, prevalently downstaging PCa compared to RE. Sensitivity and specificity for ≥T3 stage in the mpMRI validation group were 81.8% (95%C.I. 65.1-91.9) and 88.5% (72.8-96.1). CONCLUSION RE and mpMRI show moderate agreement only in assessing the T-stage of PCa, translating into an mpMRI-induced change in risk assessment in about one fifth of patients. As supported by high sensitivity/specificity for ≥T3 stage in the validation group, the discrepancy we found is in favour of mpMRI as a tool to stage PCa before ERBT.

A prospective accuracy study of Prostate Imaging Reporting and Data System version 2 on multiparametric magnetic resonance imaging in detecting clinically significant prostate cancer with whole-mount pathology

OBJECTIVE To assess the accuracy of Prostate Imaging Reporting and Data System version 2 (PI-RADS v2) in detecting clinically significant prostate cancer (csPCa) on multiparametric magnetic resonance imaging (mpMRI) using whole-mount sections after radical prostatectomy (RP) as reference standard. METHODS Forty-eight patients undergoing mpMRI before RP were prospectively enrolled. Two experienced radiologists independently scored and mapped imaging findings according to PI-RADS v2. One experienced uropathologist mapped cancers detected on whole-mount sections using the PI-RADS v2 sector scheme. Per-lesion and per-patient analyses were run. Primary outcomes were sensitivity and false discovery rate (FDR) in detecting csPCa using PI-RADS v2 score ≥3 and ≥4 as thresholds. Secondary outcome was inter-reader agreement. RESULTS On the per-lesion analysis, sensitivity and FDR at the PI-RADS v2 threshold score ≥3 were 0.75 and 0.17 for Reader 1, and 0.67 and 0.13 for Reader 2, respectively. At the PI-RADS v2 threshold score ≥4, sensitivity was slightly lower, and FDR nearly halved for both readers. On the per-patient analysis, sensitivity for csPCa at the PI-RADS v2 threshold score ≥3 was 0.85 for Reader 1, and 0.78 for Reader 2. At the PI-RADS v2 threshold score ≥4, sensitivity was slightly lower for both readers. Inter-reader agreement was substantial (k 0.72 and 0.65 for PI-RADS v2 threshold score ≥3 and ≥4, respectively). CONCLUSION In our prospective study with pathology after RP as standard of reference, PI-RADS v2 showed good sensitivity in detecting csPCa on mpMRI with substantial agreement between 2 experienced readers. Threshold score ≥4 had lower FDR.

Interreader agreement of PI-RADS v. 2 in assessing prostate cancer with multiparametric MRI: A study using whole-mount histology as the standard of reference: Assessing Prostate Cancer With mpMRI

Most studies assessing interreader agreement of Prostate Imaging Reporting and Data System v. 2 (PI‐RADS v2) have used biopsy as the standard of reference, thus carrying the risk of not definitively noting all existent cancers.