Nonpalpable breast lesions: preoperative radiological guidance in radioguided occult lesion localisation (ROLL).

PURPOSE: This study evaluated the methods, technical aspects and impact of preoperative radiological guidance in radioguided occult lesion localisation (ROLL) for single nonpalpable breast lesions. MATERIALS AND METHODS: A total of 288 patients underwent ROLL before surgery. Human serum albumin macroaggregates labelled with 3.7-7.4 MBq of technetium(99) were injected into the lesion. In the case of ultrasonographic guidance (221/288 patients), inoculum positioning resulted in a change of echogenicity at the lesion site. In the case of mammographic guidance (67/288 patients), iodinated contrast medium was injected following the radiotracer for subsequent mammographic evaluation. Patients underwent surgery within 24 h from ROLL. A gamma-detecting probe was used to locate the lesion during surgery and guide its removal. After excision, the specimen was examined by either ultrasonography or mammography to verify complete lesion removal before histological evaluation. RESULTS: The lesion was correctly localised in 281/288 patients (97.5%). One ROLL procedure failed because surgery could not be performed within 24 h and the radioactivity decayed. Of the six incorrect localisations, 2 were due to the radiological guidance and 4 to technetium(99) dispersion. CONCLUSIONS: Radiological guidance in ROLL ensured the outcome of the procedure of localisation and removal of single, nonpalpable breast lesions in the majority of cases.

Successful use of sodium hypochlorite pack plus systemic and local antibiotic therapy for the treatment of pseudomonas infection of peritoneal dialysis catheter exit-site.

Peritoneal catheter exit-site and tunnel infections remain critical problems in patients undergoing peritoneal dialysis. Catheter-related peritonitis occurs in about 20% of patients and exit-site infections are responsible for catheter removal in more than one-fifth of the cases. For the last 2 years in the Department of Nephrology, San Bortolo Hospital, Vicenza, Italy, we have been treating exit-site infections caused by Pseudomonas with sodium hypochlorite packs as well as systemic and local antibiotic therapy. Considering the encouraging results obtained on Pseudomonas infection, we decided to utilize the same schedule for the treatment of exit-site infections caused by other germs which are generally difficult to eradicate to prevent peritonitis and catheter removal. Between 2003 and 2004, 10 patients contracted infection of the exit-site. All patients underwent a swab test because of the reddening and the purulent secretion of the exit-site. The swab resulted positive for Pseudomonas in 7 patients, Corynebacterium sp. in 2 patients, and Candida albicans in 1 patient. All patients were treated with systemic antibiotic therapy or antifungal therapy, local sodium hypochlorite 50% packs. After 15 days all patients were submitted to a swab test of the exit site. In all patients, the swab test resulted negative after 15 days and 1 month, and they could continue peritoneal dialysis. This procedure avoided peritoneal catheter removal and temporary switch to hemodialysis in all patients with exit site infection. The mechanism of action is related to the wide antimicrobial spectrum and the rapid action of sodium hypochlorite possibly creating a protective barrier on the exit-site.

Acid-base balance in peritoneal dialysis.

In patients without functioning kidneys, alkali replenishment is accomplished by the addition, via dialysis solution, of either HCO 3 - itself or a metabolic precursor of this anion, such as lactate. The body base balance in peritoneal dialysis (PD) patients is self-regulated by the feedback between plasma bicarbonate concentration and dialytic base gain. Dialytic base gain is the only source of buffer for PD patients and this gain should counteract the metabolic acid production. Dialytic base gain depends on peritoneal buffer fluxes (lactate reabsorption minus bicarbonate lost). The plasma bicarbonate level is determined by the dialytic base gain and the metabolic acid production. Bicarbonate buffered PD solution provides some advantages over the conventional lactate buffered PD solution.

The ''Ronco'' catheter for continuous flow peritoneal dialysis.

To perform CFPD, a two way access must be available in order to allow continuous inflow and outflow of the solution. This is most likely achieved with a double lumen peritoneal catheter. To design a double lumen catheter does not necessarily mean to increase the size of the tube or to increase the discomfort of the patient. However, the real challenge is to find a design in which minimal re-circulation is experienced. The two tips of the catheter must be positioned such that a maximal exposure of the peritoneal surface to the fluid is guaranteed during one single passage of the fluid from one lumen to another. Double lumen catheters with one short branch and another long of straight and of spiral shape were originally designed. Ash and coworkers have designed a catheter with a t-shape configuration in order to distantiate to the maximum the tips of the two lumens. Recently we have designed a novel catheter for CFPD equipped with a thin walled silicone diffuser used to gently diffuse the inflow dialysate into the peritoneum. The holes on the round tapered diffuser are positioned to allow dialysate to perpendicularly exit 360 degrees from the diffuser. The diffuser design and hole locations disperse the high-flow dialysate fluid at 360 degrees, reducing trauma to the peritoneal walls and allowing the dialysate to mix into the peritoneum. The dispersed fluid infused into the peritoneal cavity is then drained through the second lumen whose tip is placed into the lower Douglas cavity. The new catheter with diffuser is also equipped with a special removable hub that allows for easy creation of the subcutaneous tunnel without increasing the size of the skin exit site. The results so far achieved seems to offer advantages in terms of high flows, minimal pressure regimes and negligible recirculation.

The Vicenza ''Short'' peritoneal catheter: a twenty year experience.

Dislocation of peritoneal dialysis catheters is one of the major causes of technique failure. We evaluated 701 Vicenza catheters, implanted since 1985 in 365 males, mean age 53 +/- 16 yrs, range 24 - 87, and 336 females, mean age 51 +/- 17 yrs, range 21 - 82. The Vicenza catheter is defined "short" since it consists of a classic straight double cuff PD catheter having however an inner segment (the portion located in the peritoneal cavity) much shorter than any other type of catheter. It is implanted in the lower abdomen, just a few centimeters above the pubis. The analysis of our results obtained in a large PD population displayed good device survival at 2 and 5 years (94.3% and 91.5% respectively), a low dislocation rate (4%) and an exit-site infection rate similar to other double cuffed catheters. There was no selection of patients receiving this catheter since from 1985 we have used this catheter in every incident patient. Due to its lower implantation site this catheter demonstrates excellent wearability and good body image acceptance.

Practice pattern and treatment options for kidney patients in a single North Italian nephrology center.

The experience and the current practice of a single center located in northern Italy is reported. The center of Vicenza is a self-standing nephrologic unit serving a population of about 300,000 individuals. The overall province counts approximately 800,000 individuals and some of them are referred to our center from peripheral hospitals for renal transplantation and/or particular pathologic conditions. The center offers an integrated approach to the treatment of uremia including hemodialysis (HD), peritoneal dialysis (PD), and renal transplantation. In HD and PD, the most peculiar aspect is the treatment personalization that leads to numerous types of applied therapies and technologies. The policy of the center is based on the belief that the nephrology team has a substantial influence on the outcomes of dialysis patients. A large number of treatment options are available. Special care is placed on the delivery of an adequate amount of dialysis, but the fractional clearance of urea in relation to volume (Kt/V) is seen as a prerequisite and other factors are considered important. Reduction in mortality and morbidity is largely dependent on beginning therapy early in the course of renal treatment. The attainment of appropriate hemoglobin concentrations, good nutrition, good control of calcium and phosphorus metabolism, lipids, and blood pressure, is considered of great importance. Beyond all these factors the time spent by the physician with the patient is considered one of the major factors influencing quality of care. The particularly low mortality of the center (6%/yr) may also be ascribed to a lower incidence of diabetes and other comorbidities.

Dialysate flow distribution in hollow fiber hemodialyzers with different dialysate pathway configurations.

UNLABELLED: The efficiency of a hemodialyzer is largely dependent on its ability to facilitate diffusion, since this is the main mechanism by which small solutes are removed. The diffusion process can be impaired if there is a mismatch between blood and dialysate flow distribution in the dialyzer. The objective of the paper was to study the impact of different dialysate compartment designs on dialysate flow distribution and urea clearances. Eighteen hollow fiber 1.3 m2 hemodialyzers were studied, 6 each of 3 designs: Type A--standard fiber bundle (PAN 65DX Asahi Medical, Tokyo, Japan); Type B--spacing filaments external to the fibers (PAN 65SF Asahi Medical, Tokyo, Japan); Type C--fibers waved to give Moiré structure (FB130 Nissho-Nipro, Osaka, Japan). IN VITRO STUDIES: 3 dialyzers of each type were studied following dye injection into the dialysate compartment. Dynamic sequential imaging of longitudinal sections of the dialyzer were undertaken, using a new generation helical CT scanner (X-Press/HS1 Toshiba Corporation, Tokyo, Japan). In vivo studies: 3 dialyzers of each type were studied, in randomized sequence, in 3 different patients under standardized dialysis conditions. Blood- and dialysate-side urea clearances were measured at 30 and 150 minutes of treatment. Macroscopic and densitometrical analysis revealed that flow distribution was most homogeneous in the dialyzer with Moiré structure (Type C) and least homogeneous in the standard dialyzer (Type A). Space yarns (Type B) gave an intermediate dialysate flow distribution. Significantly increased urea clearances (p<0.001) were seen with Types B and C, compared to the standard dialyzer. Type C (Moiré) had the highest clearances although these were not significantly greater than Type B (space yarns). In conclusion, more homogeneous dialysate flow distribution and improved small solute clearances can be achieved by use of spacing yarns or waved (Moiré structure) patterns of fiber packing in the dialyzer. These effects are achieved probably as a result of reduced dialysate channeling resulting in a lower degree of mismatch between blood and dialysate flows. The new radiological technique using the helical CT scanner allows detailed flow distribution analysis and has the potential for testing future modifications to dialyzer design.

Cannulation of the internal jugular vein: comparison of the classic Seldinger technique and an ultrasound guided method.

Central venous catheterization allows immediate and easy vascular access for hemodialysis. Accidental arterial puncture is the most frequent complication of central vein cannulation and may occur in up to 8% of cases with the classic Seldinger procedure. We compared the Seldinger technique which implies manual localization of the vascular access, and an ultrasound guided technique, to assess whether the latter is an improvement on the Seldinger procedure.

[The diagnostic accuracy of a digital mammography system with photostimulable storage phosphors used with automatic reading]. / Accuratezza diagnostica di un sistema di mammografia digitale con piastre fotostimolabili utilizzato con lettura automatica.

Even though digital mammography might potentially yield major advantages in management, biology and diagnosis, state-of-the-art digitalization is still in a clinical experimental phase. To assess the diagnostic accuracy of a digital mammography system with storage phosphors, we analyzed 320 digital and 320 conventional mammograms acquired in lateral-oblique projection in the same patients. Digital mammography capabilities in identifying and characterizing breast lesions were compared with those of conventional mammography; the presence/absence of lesions and their benign/malignant nature were investigated. Complete conventional mammography was our gold standard. The digital system did not miss any malignant lesion but it did miss some benign lesions (focal masses) which had been depicted with conventional mammography, especially small low-contrast opacities. Microcalcifications were better depicted on digital images which showed, at the same time, tissues of different density, thanks to their wider dynamic range. Digital mammography yielded a false positive result on a cluster of microcalcifications, because its spatial resolution is lower. The diagnostic yield of digital mammography was poorer only in the detection of small low-contrast lesions and in the characterization of microcalcifications. To conclude, in our experience, the storage phosphor system seems to be suitable for clinical mammography, but only with careful monitoring; in contrast, we think it is not yet suitable for screening purposes.

Phospholipid hydroperoxide glutathione peroxidase in the normal human kidney: a possible role in protecting cell membranes.

Reactive oxygen species have been implicated in the pathogenesis of tissue injury. It is generally accepted that selenium-glutathione peroxidases form an integrated system defending the living organism against oxidative damage. Phospholipid hydroperoxide glutathione peroxidase (PHGPX) is thought to play a prominent role in preventing lipid peroxidation. Indeed, the function of PHGPX is to reduce the lipophilic substrates in membranes. In the present study, we evaluated the expression of PHGPX in normal human kidney by immunohistochemistry. The enzyme in glomeruli is mainly expressed in podocytes and parietal epithelial cells. In addition, PHGPX antigen was detected in tubule epithelial cells. Therefore, these results suggest that renal epithelial cells possess an important antioxidizing activity related to the presence of PHGPX.

[Invasive carcinoma of the cervix uteri (Stage IB-IIB). Comparison of CT and MR for the assessment of the parametrium]. / Il carcinoma invasivo della cervice uterina (Stadio IB-IIB). Confronto TC-RM nella valutazione del parametrio.

In the patients with invasive cervical carcinoma, the accurate assessment of parametrial invasion greatly affects the therapeutic choice between surgery and radiation therapy. As a matter of fact, surgery is usually performed only in the patients with carcinoma confined to the cervix, whereas those with parametrial involvement, or more advanced stages, are treated with radiation therapy. This prospective study was aimed at investigating the comparative adequacy of CT and MR imaging in assessing parametrial status in the patients with invasive cervical cancer. Twenty-one consecutive patients, with histologic diagnosis of cervical carcinoma, were investigated. All of them were clinically considered as having invasive cervical cancer (FIGO stages IB-IIB), and subsequently underwent surgery. In all cases, detailed histology of the parametrium was obtained. Pathologic data were compared with CT and MR findings in all cases. As for assessing parametrial involvement by cancer, CT had 62% accuracy, 63% sensitivity, and 60% specificity, versus MR imaging 81% accuracy, 69% sensitivity, and 80% specificity. Therefore, MR imaging appears to be superior to CT in assessing the parametrial status of patients with invasive cervical carcinoma; the method yields valuable information for treatment planning.

[MR (1.5 T) in the evaluation of pancreas transplant rejection]. / La RM (1.5 T) nella valutazione del rigetto del trapianto di pancreas.

Graft rejection is the major cause of graft loss following pancreatic transplantation. Early detection of the rejection process is of great importance towards planning effective treatment when transplant recipients present with aspecific clinical findings suggesting rejection. Up to date, the demonstration of pancreatic transplant rejection has been attempted with nuclear medicine and sonography (US). The authors studied high-field (1.5 T) MR potentials in pancreatic transplantation and rejection and correlated MR findings with clinical and laboratory data. Eleven MR scans were obtained from 4 patients with suspected pancreatic graft rejection, and 9 MR images from 4 patients with normal pancreatic allografts. Qualitative image evaluation showed the pancreatic tissue of the patients diagnosed with rejection to be hypointense on T1-weighted scans and highly hyperintense on T2-weighted scans, as compared to normal grafts. Quantitative data were obtained by comparing the signal intensity of pancreatic grafts to that of the nearby muscle. On both T1- and T2-weighted images, pancreatic tissue/muscle signal-intensity ratios were significantly different, in rejecting transplants, from those of normal allografts (p less than 0.001). Our qualitative and quantitative findings suggest the use of MR imaging as a reliable means of detecting pancreatic graft rejection.

[Conventional radiography and digital radiography of the thorax: evaluation of anatomo-radiological parameters]. / Radiografia tradizionale e radiografia digitale del torace: valutazione di parametri anatomo-radiologici.

We report the results of a comparative study of digital and conventional chest radiographs to detect normal anatomical structures of the thorax. A digital Toshiba unit (TCR 201) was used to examine 100 selected patients who were diagnosed with no chest pathologic conditions. The images in both modes were submitted for interpretation to five radiologists. The depiction of nine normal anatomical structures was more accurate on digital than on conventional radiographs. The mean confidence levels achieved in viewing digital images were higher than those obtained with conventional radiographs. This difference was statistically significant (p = 0.002).