Colorectal duplication in adults: report of seven cases and review of the literature.

BACKGROUND: Gastrointestinal duplications are uncommon congenital abnormalities, usually recognised before the age of 2 (80%). Colorectal duplications (CDDs) occur in only 6.8% of cases, rarely in adults, and are revealed by abdominal pain and intestinal obstruction. Malignant changes are uncommon, but are most often found in the colon. METHODS AND RESULTS: During the last 7 years, the authors have observed seven cases of CDD (three men) with mean age 50.7 years (range 32-73). Four cases were revealed by abdominal pain, and three by intestinal obstruction. Five duplications were located in the caecum, one in the transverse colon, and one in the sigmoid colon. All CDDs were of the cystic type (4.42 cm, range 2-7.5), and three had a communication with the intestinal lumen. All patients except one underwent 'en bloc' resection of the cyst with the adjacent colon. On microscopic examination, CDDs contained multiple layers of the bowel wall, including colonic or small intestinal mucosa. Heterotopic gastric mucosa was observed in only one case, high-grade dysplasia in one case, and low-grade dysplasia in another. No invasive carcinoma was found. CONCLUSION: Although uncommon, CDDs should be included in the differential diagnosis of all abdominal masses. The treatment approach is excision, in order to avoid any complication. En bloc resection of the colon with CDD may be necessary, because of the intimate attachments of the common wall. Thorough sampling of the specimen is mandatory in order to detect any malignant changes.

Proximal splenic artery embolization for blunt splenic injury: clinical, immunologic, and ultrasound-Doppler follow-up.

BACKGROUND: To evaluate the clinical, US (ultrasound)-Doppler and hematologic findings after proximal splenic artery embolization (PSAE) for blunt injury. METHODS: From August 1998 to February 2003, 37 patients (28 men and 9 women; 20-89 years old, mean 40 years) underwent PSAE for blunt injuries. One patient required secondary splenectomy after PSAE. Early complications were investigated during the hospital stay. Delayed follow-up included review of the outpatient records, telephone interview, consultation, US-Doppler splenic study, Howell-Jolly body search, and serum antibody titer determinations (pneumococcus and Haemophilus influenzae B). RESULTS: No early postprocedural complications were depicted. Ten patients were lost on follow-up. Two patients had a telephone interview that revealed no complication. Twenty-four patients were examined 6 to 63 (mean 26) months after the embolization. No late complication was reported. Splenic measurements were in the normal range: length (53-110 mm; mean, 73), width (49-110 mm; 76), thickness (26-56 mm; 38), volume (61-508 mL; 226), standard ellipsoid formula volume (32-265 mL; 118), corrected volume (29-238 mL; 106), and splenic volumetric index (2.3-18.8; 8.4). The spleen was homogeneous in 23 patients (96%). Intrasplenic vascularization was present and splenic vein was patent in all patients. Howell-Jolly bodies were found in two patients. All patients (24 of 24) evaluated for exposure-driven immunity against Haemophilus Influenza b had sufficient immunity. Seventeen of the 18 patients (94%) evaluated for exposure-driven immunity against pneumococcus had sufficient immunity. Five of the six patients (83%) evaluated for pneumococcus vaccine response had a sufficient response. CONCLUSIONS: Proximal splenic artery embolization in blunt splenic injuries is a well-tolerated technique without major long-term impact on the splenic anatomy and immune function.

Clinical review: initial management of blunt pelvic trauma patients with haemodynamic instability.

Pelvic trauma can lead to severe, uncontrollable haemorrhage and death related to prolonged shock and multiple organ failure. Massive retroperitoneal haematoma should be assumed to be present in cases of post-traumatic haemodynamic instability associated with pelvic fracture in the absence of extrapelvic haemorrhagic lesions. This review describes the pathophysiology of retroperitoneal haematoma in trauma patient with blunt pelvic fracture, considering the roles of venous and arterial bleeding. Efficacy and safety of haemostatic procedures are also discussed, and particular attention is given to the efficacy of pelvic angiographic embolization and external pelvic fixation. A decision making algorithm is proposed for the treatment of trauma patients with pelvic fracture that takes haemodynamic status and associated lesions into account.

Interventional management of gastroduodenal lesions complicating intra-arterial hepatic chemotherapy.

Herein we report the efficacy of embolization of small patent gastric or duodenal vessels for treating gastroduodenal complications after hepatic arterial infusion therapy (HAIC). Catheter ports were implanted percutaneously from a femoral approach in three cases or surgically in the gastroduodenal artery in two cases. Acute abdominal pain developed on average after four HAIC courses of 5FU-oxaliplatin, mytomycin, oxaliplatin or fotemustine. Esophagogastroduodenoscopy showed gastroduodenal lesions (gastroduodenitis with or without ulcerations) in all cases. Despite the interruption of the HAIC, symptoms persisted and led to selective hepatic arteriography showing a patent right gastric artery (n = 4) or a recanalized gastroduodenal artery (n = 1) responsible for gastroduodenal misperfusion. Successful embolizations of the arteries responsible for gastroduodenal misperfusion (right gastric artery in four cases and gastroduodenal artery in one case) using 0.018 platinium coils relieved the patients' symptoms and allowed the HAIC to continue. In gastroduodenal complications of HAIC, a selective hepatic arteriography should be performed to search any artery responsible for the misperfusion of the toxic agent in the gastroduodenal area. Embolization of these arteries allowed the HAIC to be restored.

Evaluation of antiangiogenic treatment effects on tumors' microcirculation by Bayesian physiological pharmacokinetic modeling and magnetic resonance imaging.

A physiological pharmacokinetic (PBPK) model was used to estimate tumor microcirculation in nude mice with a grafted tumor. The kinetics of a rapid clearance blood pool agent, Vistarem, were investigated by dynamic MRI after bolus administration. Signal enhancements were recorded in arterial blood and in tumor tissue. To analyze these data, we developed a whole-body mathematical model of the agent's biodistribution using physiological parameters. The model included six compartments: arterial and venous plasma, tumor (split into capillaries and interstitium), and the rest of the body (also split into capillaries and interstitium). As an application, changes in tumor microcirculation parameters were evaluated in mice receiving either an antiangiogenic treatment (ZD4190) or a placebo. The analysis was performed in a Bayesian framework, and the model was fitted to experimental data using Markov Chain Monte Carlo techniques. Results showed a significant difference in tumor microcirculation between the two groups of mice when the microcirculation parameters are considered together. This whole-body physiological model enables to analyze jointly data in tumor tissue and in arterial blood. This leads to accurate estimates of microcirculation parameters and the evaluation of their uncertainty.

Nonoperative management of traumatic splenic injuries: is there a role for proximal splenic artery embolization?

OBJECTIVE: The objective of our study was to evaluate our experience with transcatheter proximal (i.e., main) splenic artery embolization (TPSAE) in the nonsurgical management of patients with grade III-V splenic injuries, according to the American Association for the Surgery of Trauma (AAST) guidelines, and patients with splenic injuries associated with CT evidence of active contrast extravasation or blush (or cases meeting both criteria). MATERIALS AND METHODS: The records of patients with traumatic splenic injuries admitted during a 52-month period were retrospectively reviewed for patient age and sex, mechanism of injury, injury severity score (ISS), RBC transfusion requirements, AAST splenic injury CT grade, presence of active contrast extravasation or blush on CT examination, and amount of hemoperitoneum on CT examination. Demographics, CT findings, transfusion requirements, and outcome were compared using the Student's t test or chi-square test in patients undergoing standard nonoperative management and nonoperative management TPSAE-that is, TPSAE followed by nonoperative management. RESULTS: Of the 79 identified patients with splenic trauma, 67 were managed nonoperatively. Thirty-seven patients (28 men, nine women; mean age, 40 years; mean ISS, 28.8) underwent nonoperative management TPSAE and 30 patients (27 men, three women; mean age, 37 years; mean ISS, 25.1) underwent nonoperative management. Age, sex, and ISS were not significantly different between the two groups. TPSAE was always technically feasible. Splenic injuries were significantly more severe in the nonoperative management TPSAE group than in the nonoperative management group with respect to the mean splenic injury AAST CT grade (3.7 vs 2, respectively; p < 0.0001), active contrast extravasation or blush (38% [14/37] vs 3% [1/30], respectively; p = 0.0005), and hemoperitoneum grade (1.6 vs 0.8, respectively; p = 0.0006). Secondary splenectomy rate was lower in the nonoperative management TPSAE group (2.7% [1/37] vs 10% [3/30]). No procedure-related complications were encountered during early and delayed clinical follow-up. CONCLUSION: TPSAE is a feasible and safe adjunct to observation in the nonoperative management of severe traumatic splenic injuries. The secondary splenectomy rate using nonoperative management TPSAE (2.7%) is among the lowest reported despite a selection of severe injuries.

Splenic arterial interventions: anatomy, indications, technical considerations, and potential complications.

Splenic arterial interventions are increasingly performed to treat various clinical conditions, including abdominal trauma, hypersplenism, splenic arterial aneurysm, portal hypertension, and splenic neoplasm. When clinically appropriate, these procedures may provide an alternative to open surgery. They may help to salvage splenic function in patients with posttraumatic injuries or hypersplenism and to improve hematologic parameters in those who otherwise would be unable to undergo high-dose chemotherapy or immunosuppressive therapy. Splenic arterial interventions also may be performed to exclude splenic artery aneurysms from the parent vessel lumen and prevent aneurysm rupture; to reduce portal pressure and prevent sequelae in patients with portal hypertension; to treat splenic artery steal syndrome and improve liver perfusion in liver transplant recipients; and to administer targeted treatment to areas of neoplastic disease in the splenic parenchyma. As the use of splenic arterial interventions increases in interventional radiology practice, clinicians must be familiar with the splenic vascular anatomy, the indications and contraindications for performing interventional procedures, the technical considerations involved, and the potential use of other interventional procedures, such as radiofrequency ablation, in combination with splenic arterial interventions. Familiarity with the complications that can result from these interventional procedures, including abscess formation and pancreatitis, also is important.

New criteria for assessing fit quality in dynamic contrast-enhanced T1-weighted MRI for perfusion and permeability imaging.

Contrast-enhanced (CE) MRI provides in vivo physiological information that cannot be obtained by conventional imaging methods. This information is generally extracted by using models to represent the circulation of contrast agent in the body. However, the results depend on the quality of the fit obtained with the chosen model. Therefore, one must check the fit quality to avoid working on physiologically irrelevant parameters. In this study two dimensionless criteria-the fraction of modeling information (FMI) and the fraction of residual information (FRI)-are proposed to identify errors caused by poor fit. These are compared with more conventional criteria, namely the quadratic error and the correlation coefficient, both theoretically and with the use of simulated and real CE-MRI data. The results indicate the superiority of the new criteria. It is also shown that these new criteria can be used to detect oversimplified models.

Percutaneous extraction of retained biliary T-tubes: a new technique.

Retained T-tubes are rare complications after biliary surgery. The authors present three cases of retained T-tubes in patients with transplanted liver that could not be removed by a standard manual traction. The authors describe a new simple percutaneous method that allows removal of these T-tubes without complication.

Malignant gastroduodenal obstruction: palliation with self-expanding metallic stents.

PURPOSE: To evaluate the feasibility, efficacy, and tolerance of self-expanding metallic stent insertion under fluoroscopic guidance for palliation of symptoms related to malignant gastroduodenal obstruction. MATERIALS AND METHODS: Seventy-two patients (38 men, 34 women) aged 25-98 years (mean, 62 years) with duodenal (n = 43), antropyloric (n = 13), surgical gastrojejunostomy (n = 10), or pyloroduodenal (n = 6) malignant obstruction were referred for insertion of self-expanding metallic stents over a 6-year period. Stent insertion was performed with use of a peroral or transgastric approach when necessary (n = 11). RESULTS: Stents were successfully inserted in 70 of the 72 patients (97%) and provided symptom relief in 65 patients (90%). Inserted stents were mainly uncovered vascular (n = 55) or enteral (n = 10) Wallstents. One hundred eight stents were initially inserted: one, two, three, or four stents were indicated in 43, 17, nine, and one patient, respectively. Mean follow-up was 119 days (range, 4-513 days). Mean stent patency was 113 days (range, 4-513 days). Mean survival of patients was 120 days. During follow-up, stent obstruction occurred in seven patients as a result of tumoral overgrowth (n = 5) or ingrowth (n = 2). Complications occurred in 12 of the 72 patients (17%), including stent migration (n = 8), stent fracture (n = 1), duodenal perforation (n = 1), and death related to general anesthesia (n = 1). CONCLUSION: Despite a significant complication rate, self-expanding metallic stent insertion under fluoroscopic guidance appears to be a feasible and useful technique in the palliative management of malignant gastroduodenal obstruction.

Multidetector CT enteroclysis: comparison of the reading performance for axial and coronal views.

The purpose of this study was to compare the diagnostic performance of axial and coronal views in multidetector CT enteroclysis (MDCTE). We retrospectively evaluated 48 patients with pathological correlation investigated by MDCTE for small bowel disorders. After nasojejunal administration of 2 l of 5% methylcellulose axial arterial and venous acquisition of MDCTE was followed by coronal reconstructions using equal slice thicknesses of 2.5 mm with 2 mm increments. Spatial resolution of both planes was evaluated by phantom. Three radiologists independently read axial and coronal images concerning 12 pathological features. The interobserver agreement and time of reading was calculated. Sensitivity and specificity resulted from comparison with histopathology (n=39) or follow-up (n=9). Phantom study revealed higher spatial resolution for axial than coronal views, whatever reconstruction interval was used. However, spatial frequency always remained high. Most pathological signs, such as bowel wall thickening (BWT), bowel wall enhancement (BWE) and intraperitoneal fluid (IPF), showed better interobserver agreement on axial than coronal views (BWT: 0.61 vs. 0.44; BWE: 0.56 vs. 0.5; IPF:0.53 vs. 0.43). The Wilcoxon signed-rank test revealed significantly higher sensitivity for axial than coronal views (P=0.0453); the time of reading was significantly shorter for the latter (P=0.0146). The diagnostic value of axial slices is superior to coronal reconstructions despite the reduced data volume and display of the physiological course of bowel loops on the coronal plane.

Glucose-receptor MR imaging of tumors: study in mice with PEGylated paramagnetic niosomes.

PURPOSE: To evaluate a magnetic resonance (MR) imaging contrast agent for tumor detection based on paramagnetic nonionic vesicles (niosomes) bearing polyethylene glycol (PEG) and glucose conjugates for the targeting of overexpressed glucose receptors. MATERIALS AND METHODS: Four gadobenate dimeglumine-loaded niosome preparations including nonconjugated niosomes, niosomes bearing glucose conjugates (N-palmitoyl glucosamine [NPG]), niosomes bearing PEG 4400, and niosomes bearing both PEG and NPG were tested. In vitro cellular uptake was measured at electron paramagnetic resonance (EPR) after incubation with human prostate carcinoma, PC3, cells. In vivo distribution was studied at MR imaging 6, 12, and 24 hours after injection, with assessment of tumor, brain, liver, and muscle signal intensity (SI) in 49 mice bearing PC3 cells. Efficiency of targeted contrast agents was assessed with tumor-to-muscle contrast-to-noise ratio (CNR). Testing for differences was performed with analysis of variance followed by a posteriori Fisher test. RESULTS: In vitro, gadolinium could be detected at EPR only in cell pellets incubated with niosomes bearing glucose conjugates or niosomes bearing both glucose conjugates and PEG (4.9. 10(-15) and 4.5. 10(-15) mol gadolinium per PC3 cell). In vivo, marked predominant tumor enhancement was demonstrated 24 hours after injection of glycosylated PEG niosomes (P <.01); no significant differences were observed following injection of nonconjugated niosomes, glycosylated niosomes, or PEG 4400 niosomes. Twenty-four hours after injection, sole presence of NPG or PEG 4400 on the surface of the niosome led to higher tumor-to-muscle CNR than that observed after injection of nonconjugated niosomes (CNR of 3.3 +/- 0.7 [SD], 3.4 +/- 2.2, and 0 +/- 1.9). Combination of NPG and PEG led to even higher tumor-to-muscle CNR (6.3 +/- 2.2). CONCLUSION: Combination of PEG and glucose conjugates on the surface of niosomes significantly improved tumor targeting of an encapsulated paramagnetic agent assessed with MR imaging in a human carcinoma xenograft model.

Interventional radiology in the management of complications after liver transplantation.

The arrival of new surgical transplantation techniques, such as split living donor or auxiliary liver transplantation, have increased the incidence of vascular and biliary complications. The causes, symptoms, and diagnostic modalities of arterial, portal caval, and biliary complications are detailed. Interventional techniques, such as balloon angioplasty and stent placement in the arterial and portal tree, as well as biliary interventional techniques, are discussed.

Enterobiliary fistula after radiofrequency ablation of liver metastases.

A 46-year-old man underwent radiofrequency (RF) ablation of three liver metastases 7 months after undergoing right colectomy for a pT2N0Mx colon adenocarcinoma. Three months after the procedure, he developed hepatic abscesses related to a fistula between the distal ileum and segment V biliary branches.

High-frequency sonography and color Doppler in the management of pigmented skin lesions.

We aimed to evaluate high-frequency sonography (HFS) coupled with color Doppler in the management of pigmented skin lesions (PSL). HFS examination was performed in 111 patients with 130 PSL. A color Doppler study was conducted in 107 lesions, to assess intralesional vascularization. Imaging findings were compared with histologic diagnosis. In the case of melanoma, sonographic and histologic maximum thickness measurements were compared. HFS showed 114 of the 130 lesions. Among the detected lesions, HFS alone provided 100% sensitivity and 100% specificity in the distinction of melanoma/nevi from other lesions, and 100% sensitivity and 32% specificity in the distinction of melanomas from nonmelanoma lesions. Sonographic and histologic measurement of melanoma thickness strongly correlated (r > 0.96, p < 0.001). Color Doppler detection of intralesional vessels had a 100% specificity and 34% sensitivity in the distinction of melanomas from other PSL. HFS coupled with color Doppler is a simple, reliable tool for PSL management.

Experience at a single institution with endovascular treatment of mechanical complications caused by implanted central venous access devices in pediatric and adult patients.

OBJECTIVE: Our objective was to describe the technical aspects and evaluate the feasibility, safety, and efficacy of endovascular management of mechanical complications related to implanted central venous devices. MATERIALS AND METHODS: One hundred fifty-six patients with cancer, who ranged in age from 3 months to 75 years (mean +/- SD, 47 +/- 18 years), were referred 290 +/- 200 days (mean +/- SD; range, 0-1202 days) after central venous device placement for retrieval of a fractured and embolized central venous device catheter (n = 100), retrieval of a guidewire embolized during placement of a central venous device (n = 2), repositioning of the migrated tip of a central venous device catheter (n = 38), and fibrin-sheath stripping (n = 16). All procedures were performed with the patient under local anesthesia on an outpatient basis, except for the eight pediatric patients. RESULTS: Ninety-five of the 100 embolized catheters and both of the guidewires were successfully retrieved. Retrieval was preceded by repositioning the embolized catheter with a pigtail catheter in 48 of these cases. Most of the procedures were performed with standard vascular tools (loop snares and pigtail catheters); the use of more sophisticated devices (grasping forceps, baskets, or balloons) rarely overcame the failure of a loop snare. Repositioning a migrated catheter tip was achieved with a pigtail catheter in 32 of 38 attempts. Of the repositioned catheters, only 24 could be used. Most of the 11 repositioning and retrieval failures were encountered because the catheter lacked a free end. Fibrin-sheath stripping was always technically successful: all these catheters were patent at 3-month follow-up. No procedure-related complications occurred. CONCLUSION: The endovascular approach is highly feasible, safe, and effective for the management of mechanical complications of central venous devices. It is probably advisable to reserve endovascular repositioning for port catheters that are cumbersome to exchange and to replace simple catheters.