Carlo Biasiutti

Characterization of cystic tumors of the pancreas: CT accuracy.

PURPOSE The purpose of this work was to evaluate the capabilities of CT to accurately characterize cystic tumors of the pancreas. METHOD Two observers retrospectively evaluated the CT exams of 100 cystic masses of the pancreas, with pathological confirmation. The two observers, blinded about clinical information and the final diagnosis, tried to categorize the lesions according to well established morphologic features. Statistical analysis was performed to measure the agreement between each radiologist and the consensus diagnosis and to evaluate the usefulness of certain CT findings in differentiating one type of cystic pancreatic neoplasm from another. RESULTS Serous cystadenoma was better diagnosed by CT [Youden misclassification index (Ymi) = 0.72] than mucinous cystic tumor (Ymi = 0.44) and solid pseudopapillary tumor (cystic variant) (Ymi = 0.47). CONCLUSION As patients with previous history of pancreatitis were excluded from the study, CT findings allowed correct characterization of only 60% of cystic pancreatic masses. Among the remaining 40%, 15-20% of the wrong diagnoses could not be corrected by means of CT, given the patterns shown by the tumors. In 20-25% of the cases, a nonspecific diagnosis of cystic mass was made.

Nonfunctioning endocrine tumors of the pancreas: Possibilities of spiral CT characterization

Abstract. The aim of this study was to assess the ability of spiral CT to adequately characterize the nonfunctioning endocrine tumors (NFETs) of the pancreas, distinguishing this lesion from the other pancreatic tumors. The spiral CT examinations of 21 cases of histologically proven NFETs, along with those of 29 cases of other pancreatic tumors and tumor-like lesions, were retrospectively reviewed in a blinded fashion by two radiologists, in order to correctly classify the lesions, highlighting the typical signs reported in the literature. Discordant cases were further analyzed in the presence of a third radiologist. The final diagnosis was acquired by means of a majority or overall consensus. The histopathologic examination was considered the gold standard. The sensitivity, specificity, and positive and negative predictive values of CT were calculated. After the consensus evaluation, the correct diagnosis was reached in 72% of cases, with 10% of nonspecific diagnoses of solid pancreatic tumor and 18% of wrong diagnoses. The sensitivity and specificity of spiral CT in identifying NFETs were 66.6 and 82.7%, respectively. The positive and negative predictive values were 73.7 and 77.4%, respectively. In up to 70% of cases the NFET demonstrates a typical aspect of a mass hyperdense in the arterial contrastographic phase eventually associated with hyperdense hepatic metastases in more than half of the patients. This finding does allow the diagnosis of NFET but without certainty indeed, since other tumors can show a similar densitometric behavior and among them particularly the ductal adenocarcinoma. On the other hand, both the solid, hypovascularized NFETs, and the cystic form, cannot be differentiated from the other solid and cystic tumors of the pancreas.

Autoimmune Pancreatitis: Possibilities of CT Characterization

Background: Pancreatitis is defined as an inflammatory disease of the pancreas, leading to morphological and pathological changes. Recently, an autoimmune pathogenesis of this disease has been proposed. This type of pancreatitis should be differentiated from other pancreatic diseases, since appropriate therapy is effective and morphological changes and pancreatic function can recover to normal levels. Aim of the Study: To assess the possibility of distinguishing autoimmune pancreatitis from other pancreatic diseases with an analogous clinical presentation on the basis of CT findings alone. Methods: The CT images of 7 patients with proven autoimmune pancreatitis, along with those of 20 patients with other pancreatic diseases, but with an analogous clinical presentation, were retrospectively evaluated in a blinded fashion by 2 radiologists. In particular, the radiologists had to search for the typical signs of autoimmune pancreatitis. Discordant cases were further analyzed in the presence of a 3rd radiologist. The final diagnosis was acquired by means of a majority or overall consensus. The sensitivity, specificity, positive and negative predictive values of CT were calculated against each of the diseases (autoimmune pancreatitis; other pancreatic diseases), in order to evaluate the diagnostic value of the scan. Results: After the consensus evaluation, the correct diagnosis was reached in 25/27 (92.5%) cases, with only 2/27 wrong diagnoses (autoimmune pancreatitis diagnosed as another pancreatic disease and vice versa). The sensitivity and specificity of CT against autoimmune pancreatitis were 86 and 95%, respectively. The positive and negative predictive values were 89 and 93%, respectively. Conclusion: Patients with autoimmune pancreatitis demonstrate imaging findings that enable the correct diagnosis by dynamic CT, even in the presence of nonspecific clinical symptoms. The precise classification of the disease is extremely important, since simple steroid therapy then represents the correct treatment, and leads to complete recovery.

Intraductal papillary mucinous tumors of the pancreas: spectrum of CT and MR findings with pathologic correlation.

Abstract. The reports of intraductal papillary mucinous tumors (IPMT) of the pancreas are increasingly more frequent in the literature. The diagnosis by means of cross-sectional imaging of these tumors is not easy, especially in the early stages, when they can mimic an inflammatory disease of the pancreas. Prompt identification of the disease is nevertheless extremely important, especially in the case of tumors originating from the collateral branches, since its recognition can modify the management of the patient, in some cases obviating recourse to surgery.

Autoimmune pancreatitis: imaging findings on contrast-enhanced MR, MRCP and dynamic secretin-enhanced MRCP.

PurposeThis study retrospectively determined magnetic resonance (MR), MR cholangiopancreatography (MRCP) and secretin-MRCP findings in patients with autoimmune pancreatitis (AIP).Materials and methodsThe MR examinations of 28 patients with histopathologically proven AIP were reviewed. In 14 cases, secretin-enhanced MRCP was performed. The observers evaluated pancreatic parenchymal enlargement, signal intensity abnormalities, enhancement, vascular involvement, bile-duct diameter and main pancreatic duct (MPD) narrowing (diffuse/focal/segmental). After secretin administration, the presence of the “duct-penetrating” sign was evaluated.ResultsMR imaging showed diffuse pancreatic enlargement in 8/28(29%) cases, focal pancreatic enlargement in 16/28 (57%) cases and no enlargement in 4/28 (14%) cases. The alteration of pancreatic signal intensity was diffuse in 8/28 (29%) cases (eight diffuse AIP) and focal in 20/28 (71%) cases (20 focal AIP). Delayed pancreatic enhancement was present in all AIP, with peripheral rim of enhancement in 8/28 (29%) AIP (1/8 diffuse, 7/20 focal); vascular encasement was present in 7/28 (25%) AIP (1/8 diffuse, 6/20 focal); distal common bile duct narrowing was present in 12/28(43%) AIP (5/8 diffuse, 7/20 focal). MRCP showed MPD narrowing in 17/28 (61%) AIP (4/8 diffuse, 15/20 focal), MPD dilation in 8/28(29%) AIP (3/8 diffuse, 5/20 focal) and normal MPD in1/8 diffuse AIP. Secretin-MRCP showed the duct-penetrating sign in 6/14(43%) AIP (one diffuse AIP with MPD segmental narrowing, five focal AIP with MPD focal narrowing), demonstrating integrity of the MPD.ConclusionsDelayed enhancement and MPD stenosis are suggestive for AIP on MR and MRCP imaging. Secretin-enhanced MRCP is a problem-solving tool in the differential diagnosis between focal AIP and ductal adenocarcinoma.RiassuntoObiettivoScopo di questo lavoro è stato valutare i rilievi di pancreatite autoimmune (AIP) nella revisione retrospettiva delle immagini di risonanza magnetica (RM), colangiopancreatografia-RM (CPRM) e CPRM con secretina.Materiali e metodiÈ stata valutata l’indagine RM di 28 pazienti con diagnosi patologica di AIP; in 14 casi è stato espletato l’esame CPRM con somministrazione di secretina. Le immagini sono state analizzate considerando i seguenti parametri: volume del pancreas, alterazioni dell’intensità di segnale del parenchima, impregnazione del pancreas, coinvolgimento vascolare, calibro delle vie biliari e restringimento (diffuso/focale/segmentale) del dotto pancreatico principale (DPP). Dopo somministrazione di secretina, è stata verificata la presenza del segno del “dotto penetrante”.RisultatiL’esame RM ha evidenziato un incremento dimensionale diffuso del pancreas in 8/28 (29%) casi, un ingrandimento di una parte del pancreas - focale - in 16/28 (57%) casi e pancreas di regolare dimensione in 4/28 (14%) casi. L’alterazione dell’intensità di segnale del pancreas era diffusa in 8/28 (29%) casi (8 AIP di tipo diffuso) e focale in 20/28 (71%) casi (20 AIP di tipo focale). Impregnazione pancreatica tardiva con “cercine” periferico iperintenso si è rilevata in 8/28 (29%) AIP (1/8 AIP di tipo diffuso, 7/20 AIP di tipo focale); “encasement” vascolare è stato dimostrato in 7/28 (25%) AIP (1/8 AIP di tipo diffuso, 6/20 AIP di tipo focale); restringimento del dotto biliare comune è stato rilevato in 12/28 (43%) AIP (5/8 AIP di tipo diffuso, 7/20 AIP di tipo focale). L’esame CPRM ha mostrato restringimento del DPP in 17/28 (61%) AIP (4/8 AIP di tipo diffuso, 15/20 AIP di tipo focale), dilatazione del DPP in 8/28 (29%) AIP (3/8 AIP di tipo diffuso, 5/20 AIP di tipo focale), e DPP normale in 1 AIP di tipo diffuso. L’esame CPRM con secretina ha fatto rilevare il segno del “dotto penetrante” in 6/14 (43%) AIP (1 caso di AIP diffusa con restringimento segmentale del DPP, 5 casi di AIP focale con restringimento focale del DPP) dimostrano l’integrità del DPP.ConclusioniAll’indagine RM e CPRM, il pattern di impregnazione tardivo e l’assotigliamento del DPP sono reperti suggestivi di AIP. La somministrazione di secretina durante l’esame CPRM è uno strumento utile nella diagnosi differenziale tra AIP di tipo focale e adenocarcinoma duttale.

Afferent loop syndrome presenting as enterolith after Billroth II subtotal gastrectomy: a case report

We present a rare late-onset (after 24 years) complication of gastric surgery with a combination of afferent loop syndrome associated with a large duodenal stone. The patient, who had undergone Billroth II partial gastrectomy for benign ulcer 24 years before, developed abdominal pain in the right upper quadrant, associated with nausea, vomiting, and high grade fever. Abnormal laboratory values included elevated liver function test, suggesting a pressure-related phenomenon. Leukocytosis and a high level of platelets were also found. Only computed tomography and endoscopy of the upper gastrointestinal tract confirmed the diagnosis of a huge stone in the dilated duodenal afferent loop. To our knowledge, a case like this has not been reported previously in the literature.

Duodenal duplication cyst identified with MRCP

Abstract. We report a case of a stalked cystic duodenal duplication. The lesion, hyperintense on T2-weighted GRE images, maintained the signal intensity after oral administration of a negative contrast agent (Lumirem, Guerbet, Aulnay-Sous-Bois, France), confirming its independence from the duodenal lumen. To our knowledge, this is the first demonstration of duodenal duplication by means of MR cholangiopancreatography.

A simplified approach to virtual colonoscopy using different intestinal preparations: preliminary experience with regard to quality, accuracy and patient acceptability

PurposeThe authors assessed the quality, diagnostic accuracy and patient acceptability of computed tomography (CT) colonography performed using a simplified bowel preparation and software for post-processing digital elimination of stool and fluid data from images compared with the examination obtained with conventional preparation.Materials and methodsTwo groups of 40 consecutive asymptomatic patients aged between 48 and 72 years underwent CT colonography. In group A, the CT scan was performed with conventional bowel preparation (a full cathartic dose and oral contrast medium to tag any residue in the 3 days preceding the study). In the second group, CT colonography was performed after a reduced bowel preparation, with the oral contrast medium for residue tagging being administered only on the day of the investigation. Examination quality, diagnostic performance and patient acceptability (rated with a self-completed questionnaire) in the two groups of patients were compared by using the McNemar test.ResultsNo significant difference was obtained with regard to examination quality (180 vs. 165 segments free from stools and fluid, p>0.05) and overall diagnostic accuracy (16/17 colonic polyps detected in group A and 12/13 in group B, p>0.05). The questionnaires revealed a greater acceptability of the reduced bowel preparation compared with the standard procedure (p=0.01).ConclusionsIn asymptomatic patients, the use of software for post-processing digital elimination of residue from images in conjunction with reduced bowel preparation does not reduce examination quality or diagnostic performance when compared with the conventional CT colonography technique and is more acceptable to and better tolerated by the patient.RiassuntoObiettivoScopo del nostro lavoro è stato valutare qualità d’esame, performance diagnostica ed accettabilità da parte del paziente della colonscopia virtuale con tomografia computerizzata (colon-TC) dopo preparazione intestinale semplificata, mediante utilizzo del software di sottrazione dei residui colici, a confronto con l’esame ottenuto mediante preparazione convenzionale.Materiali e metodiDue gruppi di 40 pazienti asintomatici consecutivi, di età fra i 48 ed i 72 anni, sono stati sottoposti a colon-TC: nel gruppo A l’esame TC è stato eseguito con preparazione intestinale convenzionale (catartico a piena dose e mezzo di contrasto orale per la marcatura dei residui nei 3 giorni precedenti l’indagine); il secondo gruppo ha eseguito la colon-TC dopo preparazione intestinale ridotta con somministrazione orale di contrasto per la marcatura dei residui solo il giorno dell’indagine. Mediante il test di McNemar sono state confrontate qualità d’esame, performance diagnostica ed accettabilità (mediante questionario autocompilativo) degli esami nei due gruppi di pazienti.RisultatiSi è ottenuta una differenza non significativa per quanto concerne qualità d’esame (180 vs. 165 segmenti liberi da feci e liquidi, p>0,05) e performance diagnostica globale (16/17 polipi nel gruppo A; 12/13 nel gruppo B, p>0,05). Dai questionari è emersa una maggiore accettabilità della preparazione intestinale parziale rispetto a quella standard (p=0,01).ConclusioniIn pazienti asintomatici, l’utilizzo di un software per la sottrazione di liquidi in concomitanza ad una ridotta preparazione intestinale, non comporta una riduzione di qualità e performance diagnostica rispetto alla tecnica colon-TC tradizionale, mentre risulta più accettabile e meglio tollerato da parte del paziente.

Percutaneous transhepatic sphincterotomy of the major papilla and stone extraction without endoscopic control

Obstructive jaundice due to an impacted stone in the common bile duct (CBD) was seen in a patient who had previously undergone Billroth II gastric resection and cholecystectomy. Surgical and endoscopic approaches to the common bile duct failed owing to pericholedochal adhesions and the excessive length of the duodenal loop. The patient was therefore treated percutaneously (sphincterotomy and stone extraction) without endoscopic control.

Imaging of Pancreatic Pseudocyst

Pseudocysts are fluid filled masses with a wall made of inflammatory and fibrotic tissue rather than a true epithelial lining. They develop from a fluid collection following a pancreatic injury and are circumscribed by a pseudo-capsule (Fig. 15.1) (Hammond et al. 2002; Kim et al. 2005). Open image in new window Fig. 15.1. Contrast enhanced CT (CECT), portal phase, axial plane: typical pseudocyst following acute pancreatitis. The lesion is characterized by homogenous fluid content and thin pseudocapsule