Magnetic resonance imaging and image analysis of post - radiation changes of bone marrow in patients with skeletal metastases.

PURPOSE: To evaluate the post-radiation lesions of the bone marrow with magnetic resonance imaging (MRI) and image analysis in patients with bone metastases undergoing radiation therapy (RT). METHODS: Thirty-five patients with bone metastases were studied from June 2008 to December 2010. All patients had osseous metastases from various primary malignancies and underwent palliative RT. MRI was performed in a Philips Gyroscan Intera 1T scanner at the beginning of RT and 12-18 days later. T1-TSE, T2-TSE and short tau inversion recovery (STIR) sequences were used. All images obtained were evaluated for early post-radiation lesions. Additionally, 1st and 2nd order textural features were extracted from these images and were introduced into a probabilistic neural network (PNN) classifier in order to create an automated classification system for those lesions. RESULTS: Changes of signal intensity in T1-TSE, T2-TSE and STIR sequences were evaluated for the presence of edema, fatty conversion of the bone marrow or areas of hemorrhage within the limits of the irradiated area. The automated classification system showed positive results in correctly discriminating the post-radiation lesions that MRI revealed. The overall classification accuracy for discriminating between pre-radiation and post-radiation lesions was 93.2%. Furthermore, the overall classification accuracy for discriminating between post-radiation lesions was 86.67%. CONCLUSION: It seems that MRI can evaluate the degree of early therapy-induced bone marrow lesions observed during the first 18 days from the beginning of RT. The proposed neural network-based classification system might be used as an assisting tool for the characterization of these lesions.

Does below-the-knee placement of drug-eluting stents improve clinical outcomes?

Modern critical limb ischemia management algorithms endorse an "endovascular first" strategy of treatment. The advent of stents coated with anti-restenotic agents that are gradually eluted to the vessel wall has revolutionized modern endovascular therapies. Several single-center, non-randomized cohort series have provided compelling data about the short- to mid-term safety and effectiveness of drug-eluting stents in below-the-knee lesions and have fuelled further large-scale research. Three multicenter randomized trials (the YUKON-BTX, the DESTINY and the ACHILLES trials) are now available and have paved the way for level I-A evidence about infrapopliteal use of drug-eluting stents. Amassed evidence strongly supports the use of olimus-eluting metal stents for focal obstructive infrapopliteal lesions in order to inhibit restenosis, prolong vessel patency and thereby achieve sustained patient improvement, as reflected by the significantly improved Rutherford-Becker classification, reduced number of repeat procedures and a trend towards improved wound healing. The present overview outlines current evidence about clinical outcomes after below-the-knee drug-eluting stent placement compared to more traditional endovascular treatments like conventional old balloon angioplasty and bare metal stents. Available evidence is appraised in the context of clinically meaningful results and relevant unresolved issues are highlighted.

Endovascular management of aortoenteric fistulas with aortic cuff extenders: report of two cases.

Despite immediate open surgery, aortoenteric fistula (AEF) remains a highly lethal condition. Endovascular management is widely employed, although there is no agreement on its role as a definite treatment or, because of a high incidence of recurrent bleeding and sepsis, as a bridge to open repair. Two cases of secondary AEFs after distant elective abdominal aortic aneurysm repair are presented. The first patient was a 76-year-old man and the second one a 70-year-old man. Both patients presented with hematemesis, had no signs of sepsis and were successfully managed with endovascular surgery, using aortic cuff extenders. Postoperative course was uneventful for both patients who were discharged on long-term antibiotics. However, during follow-up the first patient was readmitted four times; twice due to infection (at 2 and 6 months, respectively) and twice due to recurrent bleeding (at 5 and 9 months, respectively). The last episode of bleeding was managed with axillobifemoral bypass grafting, removal of the prostheses and closure of the aortic stump and the duodenal defect, but the patient died on the 5th postoperative day from multiple organ failure. The second patient remained asymptomatic until the 16th postoperative month when he developed lumbar spine osteomyelitis as a direct extension of graft infection and was deemed inoperable due to multiple comorbidities. Endovascular management of AEF can achieve satisfactory short-term results. Due to the high rate of recurrent bleeding and sepsis it should be used as a temporary measure and a bridge to open repair, whenever this is feasible.

Does ultrasound-guided lidocaine injection improve local anaesthesia before femoral artery catheterization?

AIM: To present the results of a prospective, randomized, single-centre study investigating local anaesthesia before percutaneous common femoral artery (CFA) puncture and catheterization with the use of ultrasound-guided injection of lidocaine versus standard infiltration by manual palpation. MATERIALS AND METHODS: Patients scheduled to undergo diagnostic or therapeutic transfemoral catheter-based procedures gave informed consent and were randomized in two groups. In the first arm local anaesthesia with lidocaine hydrochloride 1% was performed under ultrasound guidance (group U/S), while in the second arm the standard method of manual artery palpation was applied (group M). In both groups, subsequent CFA catheterization was achieved under ultrasound guidance. The primary study endpoint was peri-procedural pain level evaluated with a visual-analogue scale (VAS score 0-10). RESULTS: Between January 2009 and 2010, 200 patients (161 men, mean age 63±12 years) were equally assigned to each group without any significant differences in baseline demographics. Patients in group U/S experienced significantly less pain during CFA catheterization in comparison with group M with a difference of three points in mean VAS score reported (1.6±1.6 versus 4.6±1.9, p<0.0001). In addition, significantly less volume of lidocaine was used in group U/S compared to group M (16±2.7 versus 19±0.8ml, p<0.001).Total vascular access time was similar in both groups (4.4±1.3 versus 4.5±1.3min). Overall complications included two small groin haematomas in each group. CONCLUSION: Ultrasound-guided local anaesthesia of the CFA prior to percutaneous transcatheter procedures is safe and achieves superior levels of analgesia with minimal patient pain and discomfort compared to the standard method of manual palpation.

Influence of contrast media on red blood cell deformability.

Iodinated contrast media (CM) are widely used in diagnostic imaging and therapeutic interventional procedures of everyday clinical practice and are associated with multiple hemodynamic and hemorheological effects. The purpose of our work was to investigate the red blood cell (RBC) rheological properties after in vivo administration of low-osmolar or iso-osmolar CM by measuring their membrane deformability (Index of Rigidity, IR) using a filtration method. Blood samples were taken from patients who underwent digital subtraction angiography of the peripheral arteries at various times before and after intravenous administration of CM. CM included iso-osmolar Iodixanol, low-osmolar Iopromide and low-osmolar Iopentol. In the whole patient group an IR increase of 59% was calculated 5 minutes after administration of CM followed by a normalization of elevated IR values within the following hour. The 5-min IR increase was strongest in the group treated with Iopromide, whereas administration of Iodixanol was associated with a more modest transient IR increase. Intravenous injection of CM in humans may be associated with a transient but considerable decrease of RBC membrane deformability and particularly for the iso-osmolar CM the induced changes in membrane deformability seem to be more moderate.

Clinical-oriented collaboration over the Web during interventional radiology procedures.

Multidisciplinary collaboration is a key requirement in several contemporary interventional radiology procedures (IRPs). We proposed a hybrid system (NetAngio) to enable "on the fly" heterogeneous collaboration to support IRP providing intraoperating essential services, and investigate its feasibility and effectiveness in a referral medical center. We have developed a Web-based, cost-effective structure, able to support real-time mentoring, image manipulation, and education services beyond the boundaries of the single institution and potentially allow sub specialists to participate in opinion and decision making in more complex cases. Supported services based on a Motion Joint Photographic Experts Group (MJPEG) coder/decoder (CODEC) can be easily accessible by authorized collaborators, within a user-friendly interface by using a typical Web-browser. Ten interventional radiologists, two vascular surgeons and two medical physicists participated in 33 "fully collaborative" cases during a 13-month period from January 2004 to February 2005. In addition, fifteen 90-minute open seminars and finally, 75 expert's module activations, and 255 learner's module activations were performed during the evaluation period. Collaborative procedures are able to enhance outcomes performance especially in more complex cases where the simultaneous presence of a remote expert interventionist and a medical physicist or a surgeon is required. Further research is needed to promote integration of additional data sources and services.

Ureteral injuries during gynecologic surgery: treatment with a minimally invasive approach.

PURPOSE: To report the safety and efficacy of percutaneous nephrostomy and primary antegrade recanalization for treatment of iatrogenic ureteral strictures after gynecologic surgery. PATIENTS AND METHODS: Ten women had symptoms suggestive of ureteral obstruction during the immediate postoperative period (5 days-1 week after surgery). Under analgesia and conscious sedation, standard percutaneous nephrostomy was performed, and a long 7F sheath was placed in the upper ureter. The obstructions were traversed with the aid of a 0.0035-inch Glidewire and a 5F angled Glide catheter (Terumo, Japan). Subsequently, the areas were dilated with angioplasty balloons to a maximum diameter of 7 mm. Finally, an 8F percutaneous internal/external nephroureteral drainage stent was inserted to secure ureteral patency. Follow-up was carried out by serial nephrostomography until removal of the stent and by renal ultrasonography thereafter. RESULTS: Twelve obstructions with a mean length of 1.4 cm (range 0.4-1.9 cm) were managed. The technical success rate was 100%. No major complications occurred, and normal renal function was restored. The mean follow-up was 12 months. In 60% of the patients, a patent ureter was depicted at 1 week, whereas in four patients, repeat dilation of the obstructed segment was required. The stents were removed after a mean period of 4.8 weeks. CONCLUSION: Percutaneous nephrostomy and primary antegrade ureteral balloon dilation is safe and efficacious for treating ureteral injury after pelvic surgery and obviates open surgical manipulations.

Valgus impacted proximal humeral fractures and their blood supply after transosseous suturing.

We treated 16 patients (11 women and five men, average age 45 years), all having four-part valgus impacted fractures of the proximal humerus, with transosseous suturing. All had preoperative angiography performed 6-12 h after admission. The average impaction angle was 43 degrees , and the mean lateral displacement of the humeral head was 1.4 mm. Postoperative angiography was performed 8-10 weeks after the operation followed by digital image processing using the segmentation technique. No statistically important reduction in the length and area of large (>0.5 mm) vessels was seen. Union was confirmed by the reduction in the length and area of small vessels (<0.5 mm). At a mean follow-up of 40 months, avascular necrosis was only found in one patient. The average Constant-Murley score was 87 (67-100) points, whereas the functional score in comparison with the unaffected shoulder was 94% (89-100%). Despite the small number of patients, transosseous fixation seems to preserve the remaining blood supply of the humeral head.

Coated v noncoated ureteral metal stents: an experimental model.

PURPOSE: The purpose of the present study was to compare the standard metal stents with internally and externally coated metal stents in the pig model. MATERIALS AND METHODS: In nine female pigs weighing between 25 and 30 kg, the metal stents were randomly placed in either the right or left ureter, for a total of 18 stented ureters. Six ureters were stented with a Wallstent (Schneider, Zurich, Switzerland), six with a Passager stent (Boston Scientific, Natick, MA, USA), and six with a Corvita endoluminal graft (CEG) (Boston Scientific, Natick, MA, USA). Patency was examined by nephrostotomography 24 hours and 21 days after the initial procedure. RESULTS: Free flow of urine through the stents into the bladder was revealed in all ureters with the exemption of four cases where a Passager stent migrated into the bladder, jeopardizing ureteral patency. The Wallstent generated mild inflammation with metaplasia of the urothelium; the CEG a more pronounced inflammatory response in the adjacent ureter; and the Passager stent severe inflammatory reaction with necrosis of the urothelium. The sections of the Wallstents revealed the presence of a mild polypoid reaction adherent to the internal surface of the devices. The coated stents showed no tissue ingrowth through the lining material into the ureteral lumen, and thus, the urothelium was compressed beneath the prostheses. CONCLUSIONS: Our experimental results suggest that the standard Wallstent generates less inflammation of the surrounding tissues than coated stents. The coated stents have the advantage of minimal tissue ingrowth but have a tendency to migrate toward the bladder.

Quantification of the ionising radiation effect over angiogenesis in the chick embryo and its chorioallantoic membrane by computerised analysis of angiographic images.

PURPOSE: We evaluated, in vivo, the effect of ionising radiation on the angiogenesis process in the chick embryo and its chorioallantoic membrane (CAM) using digital subtraction angiography (DSA) in conjunction with computer-assisted image analysis. Information regarding the ionising effect on endothelial cells during radiation treatment was extracted. MATERIAL AND METHODS: Two series of fertilized eggs were irradiated with a single ionising radiation dose of 10 Gy on days 9 and 13 of embryonic development. Angiography was carried out 24 h after irradiation. The angiographic images were digitized and subsequently processed. A set of specific morphological parameters was defined to allow an analytical characterization of the vascularity status. Vessels were classified into three categories according to their diameters (> or = 200 microm, 100-200 microm and 50-100 microm). The data were normalized and statistically evaluated. RESULTS: On day 10, total vascular area and total vascular length presented a 15.6+/-1.2% and 18.4+/-2.4% reduction, respectively, while vascular diameters increased 3.3+/-0.5%. The vessel area and length of the first category > or = 200 microm) increased 9.8+/-1.1% and 8.1+/-0.9%, respectively, while these morphometric parameters for each of the remaining two categories decreased 44.3+/-2.9%, 38.7+/-4.2% and 45+/-3.8%, 30.7+/-3.4%, respectively. On day 14 insignificant changes were observed. CONCLUSION: Computerised analysis of angiographic images showed that the antiangiogenic effect of irradiation during the various phases of CAM development is larger on the 10th day than that observed on day 14 and it depends on the vessel size.

VDD pacing from the middle cardiac vein via a persistent left superior vena cava.

We report a combination of unusual features demonstrating a permanent pacemaker implantation of a single-pass VDD lead by way of an anomalous persistent left superior vena cava in the middle cardiac vein. The ventricular stimulation resembled a right bundle branch block QRS morphology and was successfully synchronized by spontaneous atrial activity. This case illustrates an alternative approach of effective VDD pacing and sensing in patients with such a venous anomaly when other standard implantation sites fail.

Metal stents for the management of atherosclerotic renovascular disease.

PURPOSE: We report on our experience with the use of metal stents for the treatment of atherosclerotic renovascular disease. PATIENTS AND METHODS: Since 1996, 62 patients (mean age 67 years) with ostial atherosclerotic renal artery stenosis were treated successfully by placement of metal stents. All patients presented with renovascular hypertension, and eight had additionally impaired renal function. In 12 patients, stents were placed bilaterally. In 54 patients, the introduction of stents was performed as the primary mode of treatment, and in the remaining 8 patients, the positioning of the endoprosthesis was deemed necessary because of recurrence of stenosis previously treated by renal percutaneous transluminal angioplasty (PTA). The patients were followed for a mean period of 18 months (range 9-48 months). RESULTS: Positioning of the endoprosthesis was successful in all patients. No major complications were reported. The 18-month patency rate was 77.4% (48 patients). Hypertension resolved in 39 patients and showed a trend to improvement in 15 patients. We observed no improvement of renal function in the eight patients who had impaired function prior to the procedure. CONCLUSION: Implantation of metal stents is a safe and effective method for the treatment of atherosclerotic renal artery stenosis and certainly presents an important alternative to renal PTA.

Liposome-coated metal stents: an in vitro evaluation of controlled-release modality in the ureter.

PURPOSE: In vitro preparation of liposome-covered metal stents and loading of liposomal drug formulations that will slowly release the drug in the vicinity of the stent. MATERIALS AND METHODS: Polytetrafluoroethylene-coated stents were used. Large multilamellar (MLV) liposomes (phosphatidylcholine:cholesterol 1:1 mol/mol), empty or entrapping the corticosteroid anti-inflammatory drug, dexamethasone, were prepared by the thin-film hydration method and applied to pieces of stent using a simple and mild evaporation technique. Initially, a freeze-drying method for applying liposomes to stents was also evaluated, but it failed to produce stents that efficiently retain liposomal lipid when incubated in an aqueous environment. The presence of liposomes on the stent surface was confirmed by scanning electron microscopy. RESULTS: After analyzing the release of liposomal lipid (using a phospholipid assay) and liposomal drug (by a modified dexamethasone high-pressure liquid chromatography method) in an in vitro system developed to simulate in vivo conditions, it was found that 39.11+/-6.8% of the lipid and 50.84+/-5.48% of the drug was released from the stent pieces during 48 hours of incubation in the presence of artificial urine. The amount of dexamethasone released from stents during their application procedure was found to be negligible in an in vitro dry run. CONCLUSION: The use of stent-associated liposomal drug formulations as slow-release depots could be an efficient method of treating the untoward event of ureteral stent obstruction.

Encrustation of a metal alloy urinary stent: a mechanistic investigation.

MATERIALS AND METHODS: A section of a metal stent consisting mainly of tantalum coated partially by strongly adhering calcium oxalate monohydrate (COM) crystals was immersed in supersaturated solutions prepared from calcium chloride and sodium oxalate at 37 degrees C and ionic strength 0.15 M in NaCl. Abstract OBJECTIVES: To investigate the kinetics of encrustation of a metall alloy urinary stent system in vitro by calcium oxalate and characterize the crystals forming from solutions supersaturated with respect to all calcium oxalate hydrates. RESULTS: The COM-coated stent mineralized upon immersion in the supersaturated solutions. The process was monitored with a calcium ion-selective electrode and the rates were measured at conditions of sustained solution supersaturation. COM crystals formed on the stent and the rate of COM crystal growth yielded a second-order dependence on the solution supersaturation. CONCLUSIONS: The deposition of COM crystals on the metal stents coated partially with COM crystals by adhesive forces was found to be most important for the acceleration of the encrustation process. The dependence of the rates on the solution supersaturation suggested absence of secondary nucleation and a surface-controlled process for the encrustation process.

Metallic stents in gynecologic cancer: an approach to treat extrinsic ureteral obstruction.

OBJECTIVE: We report on our experience with the use of self-expandable metal stents for the treatment of extramural ureteral obstruction in patients with gynecologic cancer to restore ureteral patency and to alleviate the ureterectasis and hydronephrosis proximal to the ureteral narrowing. METHODS: Fourteen women (mean age 48 years) with obstructive uropathy secondary to gynecologic malignancies were treated successfully by placement of Wallstent self-expandable intraureteral metallic stents. The patients were followed for a mean period of 15 (range 9-24) months. RESULTS: Obstructive uropathy was resolved in all cases. In 1 patient placement of an additional, totally coaxial, stent was considered necessary because of tumor ingrowth, occurring 6 months after the procedure. In another patient, tumor overgrowth invading the borderline area between the proximal ureteric end and the metallic prosthesis was seen 12 months after stent placement causing obstruction. Thus, an additional Wallstent was implanted overlapping the initially placed stent. Patency was achieved in all the remaining ureters, during the follow-up period, without any need for further intervention. CONCLUSION: Implantation of self-expandable metal stents is a safe and effective method for bypassing ureteral obstruction due to gynecologic malignancies.

Percutaneous treatment of large symptomatic renal cysts.

PURPOSE: To evaluate the efficacy of alcohol in combination with tetracycline for the treatment of symptomatic renal cysts. PATIENTS AND METHODS: Twenty-four patients age 45 to 77 years (mean 66 years) with a large (5-13-cm; mean 7.5-cm) symptomatic renal cyst associated with flank pain were treated by aspiration under ultrasound guidance and injection of alcohol and tetracycline. Patients were followed with ultrasonography at 1, 6, and 12 months and once a year thereafter. RESULTS: The aspirated volume ranged from 65 to 1500 mL (mean 360.5 mL). Two patients experienced mild pain during alcohol injection, but the procedure was completed successfully. One patient reported severe pain after tetracycline injection. The tetracycline was immediately aspirated, and the procedure was then aborted. The remaining patients were relieved of their symptoms after treatment, and they remained symptom free during a mean follow-up of 20 months (range 7-36 months). CONCLUSIONS: The combination of alcohol and tetracycline is safe and effective and offers a very favorable minimally invasive therapeutic alternative for the treatment of symptomatic renal cysts.

Quantitative assessment of angiogenesis in the chick embryo and its chorioallantoic membrane by computerised analysis of angiographic images.

We studied, in vivo, the angiogenesis process in the chick embryo and its chorioallantoic membrane (CAM) using digital subtraction angiography (DSA) in conjunction with computer-assisted image analysis. In a series of fertilised eggs, angiography was carried out at days 8, 10, 12 and 14 of embryonic development. The angiographic images were digitised and subsequently processed for a specific image analysis. A set of specific morphological parameters has been defined to allow an analytical characterisation of the vascularity status. Vessels were classified into three categories according to their diameter (50-100, 100-200, and > 200 microm). The data were normalised and statistically evaluated. Graphs showing the development of angiogenesis were obtained. Total vascular area revealed a continuous rise, whereas, total vascular length increased until day 12 and then it started decreasing. These morphometric parameters in the first two vessel categories progressively increased throughout the entire period of development, whereas in the third category they increased until day 10 and then they started decreasing. By applying a vascular casting technique CAM vessels were visualised and compared with those extracted from the processed angiographic image. The comparison revealed that there is exact matching for the first two vessel categories (diameters higher than 100 microm) while the matching of the third category (diameters between 50 and 100 microm) is approximate.

Aortocaval fistula in ruptured aneurysms.

OBJECTIVES: to study incidence, clinical presentation and problems in management of aortocaval fistula in our series. DESIGN: retrospective study. MATERIALS: during a seven-year period, 112 patients operated on for abdominal aortic aneurysm, including four patients with aortocaval fistula. METHODS: standard repair of aortocaval fistula from inside the aneurysmal sac was the preferred operative technique. RESULTS: the incidence of aortocaval fistula was 3.6%. Three cases were found incidentally during emergency surgery for ruptured aneurysms; the fourth case was an isolated aortocaval fistula associated with inferior vena cava thrombosis, diagnosed preoperatively by angiography. In this case, inferior vena cava ligation instead of standard aortocaval repair was performed. CONCLUSIONS: Aortocaval fistulas, although rare, should be kept in mind, because clinical diagnosis is often difficult. Furthermore, unsuspected problems during repair may necessitate appropriate change in operative technique.

Treatment of varicocele for male infertility: a comparative study evaluating currently used approaches.

OBJECTIVE: To evaluate the results of four currently used approaches for the treatment of clinically diagnosed varicoceles, and compare their influence on semen parameters. METHODS: We prospectively evaluated 88 patients, 23-39 years old (mean age 31), with a clinically diagnosed varicocele. Patients were allocated randomly to be treated either by a retroperitoneal (group A), inguinal (group B), subinguinal (group C), or percutaneous venous embolization approaches (group D). All patients were evaluated 6 and 12 months postoperatively. RESULTS: Clinical recurrence of varicocele occurred in 4 patients of group A (18.2%), 1 patient of group B (4.5%), and 2 patients of group D (9.1%). Hydrocele formation was seen in 1 patient of group B (4.5%), and 2 patients of group C (9.1%). In all groups statistically significant improvement as to the sperm concentration was found in both the 6- and 12-month follow-up. This significance was more prominent in group C followed by groups B and D, and finally by group A. As to sperm motility, in group C there was a statistical significance in both follow-up evaluations, and in group B statistical difference was reached only in the 12-month evaluation. Sperm morphology did not differ in any of the groups postoperatively compared to the preoperative values. CONCLUSIONS: The subinguinal approach disclosed a more prominent improvement in both semen concentration and motility in the 6- and 12-month follow-up evaluation when compared to the other techniques. Furthermore, due to its simplicity and avoidance of opening the external oblique fascia, we believe it represents the more plausible approach when treating clinical varicocele.