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M Esposito

Publications and source records attributed to M Esposito.

At least 73 records · Page 4Linked to original sources
PubMed2000

Histopathologic observations on late oral implant failures.

BACKGROUND: Despite good success rates of osseointegrated oral implants, failures do occur. To minimize losses, failure mechanisms should be elucidated. PURPOSE: This study sought to describe the morphology of tissues surrounding late failed Brånemark implants in relation to their clinical and radiographic findings to acquire a better understanding of the etiologic factors. MATERIAL AND METHODS: Ten failed implants and their surrounding tissues were consecutively retrieved from nine patients after prosthesis placement (late losses). On radiographs, a radiolucent line was visible around nine clinically mobile implants. Tightening of the abutment screw evoked pain at seven mobile implants. Clinically, no other visual inflammatory sign or symptom was manifest. A fistula originated from one stable implant, surrounded on radiographs by a diffuse bone rarefaction. Retrieved implants were electrochemically dissolved. Intact tissue-implant thin (1 micron) and ultrathin (70-80 nm) sections were analyzed with light and transmission electron microscopy. RESULTS: Peri-implant marginal tissues displayed moderate inflammatory infiltrates located adjacent to and beneath the junctional epithelium. One patient affected by oral lichen planus displayed an intense lymphocyte/plasma cell-dominated immune reaction. Deep peri-implant tissues surrounding mobile implants consisted of a dense, fibrous tissue capsule with minimal inflammation. Epithelial downgrowth was observed around four implants. Small areas of nonmineralized bone in contact with the implant were noticed in the apical portion of two implants. One implant was almost entirely colonized by bacterial plaque with the exception of its apical portion, where bone-implant contact was observed. The stable implant was characterized by bone-implant contact. CONCLUSION: Altogether clinical, radiographic, and histologic findings indicated that two major etiologic factors might have been implicated in the failure process of the investigated implants: excessive occlusal load in relation to the bone-supporting capacity and, in two cases, infection.

Aged↗
PubMed2000

Sequence effect of epirubicin and paclitaxel treatment on pharmacokinetics and toxicity.

PURPOSE: Sequence-dependent clinical and pharmacokinetic interactions between paclitaxel and doxorubicin have been reported. Some data have shown an influence of paclitaxel on epirubicin metabolism, but no data are available about the effect of diverse sequences of these drugs. We investigated whether reversing the sequence of epirubicin and paclitaxel affects the pattern or degree of toxicity and pharmacokinetics. PATIENTS AND METHODS: Patients receiving epirubicin 90 mg/m(2) by intravenous bolus followed by paclitaxel 175 mg/m(2) over 3-hour infusion or the opposite sequence every 3 weeks for four cycles were eligible. Toxicity was recorded at nadir. Pharmacokinetic data were evaluated at the first and the second cycle and were correlated with toxicity parameters. RESULTS: Thirty-nine consecutive stage II breast cancer patients were treated. Twenty-one patients received epirubicin followed by paclitaxel (ET group), and 18 received the opposite sequence (TE group). No significant difference in nonhematologic toxicity was seen. A lower neutrophil and platelet nadir and a statistically significant slower neutrophil recovery was observed in the TE group. Area under the concentration-time curve (AUC) of epirubicin was higher in the TE group (2,346 ng/mL. h v 1,717 ng/mL. h; P =.002). An inverse linear correlation between epirubicin AUC and neutrophil recovery was also observed (P =.012). No difference was detected in paclitaxel pharmacokinetics. CONCLUSION: Our results support a sequence-dependent effect of paclitaxel over epirubicin pharmacokinetics that is associated with increased myelotoxicity. Because schedule modifications of anthracyclines and paclitaxel can have clinical consequences, the classical way of administration (ie, anthracyclines followed by paclitaxel) should be maintained in clinical practice.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2000

An unusual variant of composite lymphoma: a short case report and review of the literature.

We recently encountered an unusual case of composite lymphoma arising in a 73-year-old man with a history of follicular small cleaved cell lymphoma. The neoplasm was composed of follicular small cleaved cell lymphoma and nodular sclerosing Hodgkin disease within a single groin lymph node. In addition to morphologic evidence, the immunologic studies performed in this case demonstrated the simultaneous occurrence of 2 separate lymphocytic proliferations. To the best of our knowledge, only one such histologic type has been reported in the literature.1 Hodgkin lymphoma can develop in patients with non-Hodgkin disease and vice versa, especially after treatment. The simultaneous occurrence of Hodgkin disease and non-Hodgkin lymphoma in a single lymph node is extremely rare. In this article, the relationship between Hodgkin disease and non-Hodgkin lymphoma is explored, possible explanations for the occurrence of composite lymphoma are discussed, and the literature is reviewed.

Aged↗
PubMed2000

Reduction of cisplatin nephrotoxicity by procainamide: does the formation of a cisplatin-procainamide complex play a role?

Procainamide protects mice bearing P388 leukemic cells against the toxicity of cisplatin without diminishing antitumor activity. The mechanism of action of procainamide protection was investigated both in vitro and in vivo. HPLC studies showed that procainamide forms a complex with cisplatin in vitro that has a UV spectrum similar to that of DPR, a triamine platinum complex that contains procaine as ligand. We report here the effect of the reaction product of cisplatin and procainamide on both cisplatin-induced DNA interstrand cross-links (ISCLs) and on the total DNA platination of isolated DNA. Total DNA platination in vitro of isolated DNA was increased by 113% (P <.01) and 17% (P <.05) after incubation times of 1.75 and 6 h, respectively, compared with products from the reaction of cisplatin with water. Furthermore, the reaction product of cisplatin and procainamide was bound to DNA to a significantly greater extent than was cisplatin itself. ISCLs were decreased by 41% when this drug combination was incubated with DNA for 1.75 h, but no changes were observed after incubation for 6 h. We also examined the influence of the time interval between administration of cisplatin and procainamide on normal kidney injury, the renal distribution and urinary excretion of platinum, and the formation of cisplatin-DNA adducts in renal tissue of Sprague-Dawley rats after i.p. administration of 7.5 mg/kg cisplatin either with or without procainamide. The plasma concentrations of urea and creatinine and kidney histology demonstrated that procainamide provided effective protection in vivo in the rat when administered either simultaneously or at 0.5 and 1 h before or after cisplatin. The protection was accompanied by both higher renal levels of platinum and cisplatin-DNA adducts and by an increase in the formation of ISCLs. Moreover, a dose-dependent reduction of urinary excretion and concentration of platinum was also observed. We propose that procainamide, after accumulation in the kidney, may coordinate with cisplatin to form a less toxic DPR-like complex that renders rats less susceptible to cisplatin-induced toxicity.

Animals↗
PubMed2000

[Multiphasic helical computerized tomography of hepatocarcinoma. Assessment after chemoembolization].

PURPOSE: To report our personal experience with the addition of contrast-enhanced multiphase helical CT to unenhanced CT (Lipiodol CT) in the evaluation of patients with hepatocellular carcinoma treated with chemoembolization and to analyze the present role of oily agent CT. MATERIAL AND METHODS: We retrospectively reviewed the examinations of 42 consecutive patients submitted to global chemoembolization over a 2-year period. CT was performed 18-30 days after the treatment. The Lipiodol CT study was carried out with volume acquisitions. We considered as nodules all well-defined areas with dense oily agent uptake; uptake itself was classified as: 0 = absent, I = lower than 10% of the tumor volume, II = lower than 50%, III = higher than 50%, IV = homogeneous. Contrast-enhanced helical CT was performed with the 2-phase technique in 28 patients and with the 3-phase technique in 14; we considered as nodules all well-defined and relatively homogeneous areas with hyperattenuation in the arterial phase and hypo-isoattenuation in the portal and/or delayed phase, or with hypo-isoattenuation in the arterial phase and in the portal and/or delayed phase. RESULTS: Lipiodol CT permitted to recognize 65 nodules (1-5/patient, mean 1.5), namely 15 grade I, 21 grade II, 20 grade III and 9 grade IV. Multiphase CT identified 6 additional nodules in 5 patients, 5 hypervascular and 1 hypovascular, and better assessed the correct morphology and volume of grade I nodules. Only 4 of 6 nodules missed on Lipiodol CT showed oily agent uptake after a new chemoembolization session. Moreover after retreatment, carried out in 6 of 9 patients with grade I uptake (11 nodules in all), we found persistence of the grade I pattern in 5 nodules, grade II in 5, and grade III in 1. CONCLUSION: Lipiodol CT may miss liver nodules and underestimate the volume of nodules with poor uptake. Though Lipiodol CT should still be considered slightly more sensitive than multiphase CT, in our opinion this technique has several limitations, as also shown in recent literature papers, and its clinical applications should be reduced. Multiphase helical studies may provide useful information and should be performed routinely in patients treated with chemoembolization. The present availability of alternative tools such as contrast-enhanced Doppler US and MRI should also be stressed and their potential role investigated.

Adult↗
PubMed1999

Human transaldolase and cross-reactive viral epitopes identified by autoantibodies of multiple sclerosis patients.

Multiple sclerosis is mediated by an autoimmune process causing selective destruction of oligodendrocytes. Transaldolase, which is expressed in the brain selectively in oligodendrocytes, is a target of high affinity autoantibodies in serum and cerebrospinal fluid of multiple sclerosis patients. A three-dimensional model of human transaldolase was developed based on the crystal structure of the enzyme from Escherichia coli. To identify immunodominant epitopes, 33 peptides overlapping human transaldolase by 5 amino acids were synthesized. Ab 12484, raised against enzymatically active human transaldolase, recognized antigenic determinants corresponding to linear epitopes (residues 27-31 and 265-290) and alpha helices (residues 75-98 and 302-329). Four immunodominant peptides harboring charged amino acid residues with topographically exposed side chains were identified by sera from 13 multiple sclerosis patients with predetermined autoreactivity to transaldolase. Autoantibodies binding to the most prominent human transaldolase epitope, between residues 271 and 285, showed cross-reactivity with Epstein-Barr and herpes simplex virus type 1 capsid-derived peptides. Molecular mimicry between immunodominant autoepitopes and viral Ags may be a decisive factor in directing autoimmunity to transaldolase in multiple sclerosis patients.

Amino Acid Sequence↗
PubMed1999

Surface analysis of failed oral titanium implants.

The aim of the present study was to investigate the surface topography, composition, and oxide thickness of consecutively failed, oral Brånemark implants in order to determine possible causes for failure. The failure criterion was lack of osseointegration manifested as implant mobility. Ten implants were retrieved before loading (early failures) and 12 during a period of function up to 8 years (late failures). At retrieval, early losses did not display any clinical sign of infection. All late failures were radiographically characterized by peri-implant radiolucency and did not show infectious signs with one exception. No implant seemed to be lost due to peri-implantitis (plaque-induced progressive marginal bone loss). Twelve implants were analyzed by scanning electron microscopy (SEM), Auger electron spectroscopy (AES), and depth profiling using a blind protocol. Two pristine fixtures, which underwent the same preparation as the failed implants, were used as controls. In the SEM, control samples were essentially free from macroscopic contamination, whereas failed implants contained varying amounts of tissue residues. AES showed that all surfaces consisted of Ti oxide and varying amounts of additional elements, with C dominating in most cases. Nitrogen and sometimes Na, Ca, P, Cl, S, and Si were detected. The Si contamination was most likely due to ion leaching from the glass vials used for storage. Depth profiles showed a typical oxide thickness of 5-8 nm for all samples. In conclusion, no significant changes in the oxide layer composition or thickness as a result of implantation were observed. The results do not indicate any material-related cause for the failures of these implants. Possible reasons for these failures were impaired healing, asymptomatic infection, and overload.

Adult↗
PubMed1999

Pleural space perfusion with cisplatin in the multimodality treatment of malignant mesothelioma: a feasibility and pharmacokinetic study.

INTRODUCTION: Malignant pleural mesothelioma is an ideal model for testing new locoregional multimodality approaches because of its aggressive local behavior. METHODS: This study was planned to investigate the feasibility, safety, and pharmacokinetics of a multimodality therapy including an operation, pleural space perfusion (60 minutes) with cisplatin (100 mg/m2), hyperthermia (41. 5 degrees C), and postoperative radiotherapy (55 Gy to chest wall incisions). The effects of the extent of resection and perfusion temperature on cisplatin pharmacokinetics were evaluated. Ten patients with epithelial or mixed, stage I or II, malignant pleural mesothelioma underwent the following procedures: group A (3 patients), pleurectomy/decortication and normothermic pleural space antineoplastic perfusion; group B (3 patients), pleurectomy/decortication and hyperthermic perfusion; and group C (4 patients), pleuropneumonectomy and hyperthermic perfusion. Operations were selectively applied depending on tumor extent. Platinum levels were serially measured by atomic absorption in systemic blood, perfusate, lung, and endothoracic fascia. RESULTS: The overall procedure was completed in every case, without any death or toxicity. No lung damage was demonstrated after treatment. Major complications included 1 wound infection and 1 diaphragmatic prosthesis displacement. The mean peak platinum plasma levels were reached within 45 to 60 minutes after perfusion was started. Systemic drug concentrations were greater after pleurectomy/decortication than after pleuropneumonectomy (P =.006). The local tissue/perfusate ratio of platinum concentrations tended to be higher after hyperthermic perfusion rather than normothermic perfusion. CONCLUSION: This multimodality approach is feasible, pharmacokinetically advantageous, and safe enough to undergo further clinical investigations.

Adult↗
PubMed1999

Percutaneous nephrostomy as adjunct management in advanced upper urinary tract infection.

OBJECTIVES: To determine by retrospective review of 315 percutaneous nephrostomies, performed for pyonephrosis, whether this intervention has major clinical advantages. METHODS: From 1977 to 1996, under the direct supervision of the senior author of this report (E.K.L.), at seven hospital sites, 315 patients (181 males, 134 females; 17 to 88 years of age) were treated with percutaneous nephrostomy and antibiotic therapy for infected hydronephrosis. RESULTS: Additional or disparate pathogens were identified in 116 (36.8%) of 315 patients, leading to a clinically significant change in, or addition of, antibiotics and/or antifungal agents in 84 (73%) of 116. Most notably, we often found a clinically important disparity between the results of cultures obtained from the nephrostomy and those obtained from bladder-urine specimens. CONCLUSIONS: This retrospective review confirms previously reported advantages of percutaneous upper urinary tract drainage as a potentially life-saving adjunct in the treatment of pyonephrosis. Several case studies highlight the advantage of this maneuver in difficult cases involving obstruction due to extensive fungus or debris. In particular, our review focuses attention on the clinically important insight that urine cultures from percutaneous nephrostomy drainage often identify pathogens that differ from those detected in concurrent bladder cultures.

Humans↗
PubMed1999

Cisplatin combined with tiopronin or sodium thiosulfate: cytotoxicity in vitro and antitumor activity in vivo.

We have previously reported that the thiol compound tiopronin protects rat kidneys in vitro against the toxic activity of cisplatin. The influence of tiopronin and sodium thiosulfate (STS) on the cytotoxicity of cisplatin has been investigated on P388 leukemic cells in vitro after 3 days. The combination has also been investigated in vivo in BDF1 mice bearing a P388 s.c. tumor. In contrast to STS, tiopronin did not significantly reduce the cytotoxic activity of cisplatin in vitro and nor did it affect the uptake of platinum (cisplatin-derived), binding to DNA or the percentage of interstrand cross-links (%ISCL) formation. The co-administration of cisplatin (4 mg/kg) and tiopronin (150 and 300 mg/kg) to BDF1 female mice bearing a s.c. P388 tumor produced a significant reduction in tumor growth similar to that of a single 6 mg/kg dose of cisplatin. Interestingly, pre-incubation in vitro of either tiopronin or STS for 2 h with the species formed from cisplatin by hydrolysis demonstrated their ability in inhibiting the cytotoxicity of these reactive platinum products. These results indicate that tiopronin does not reduce the cytotoxicity of cisplatin in vitro, as STS does. This may be, at least partly, because of a different effect of the two thiol compounds on the cellular uptake and binding of platinum to DNA. Notably, tiopronin substantially reduced tumor growth in mice treated with a non-toxic dose of cisplatin (p < or = 0.0277), suggesting some positive influence of this thiol compound on the antitumor properties of cisplatin. The ability of tiopronin to protect in vitro against the cytotoxicity of the aquation products of cisplatin may be related to its nephroprotective effect.

Animals↗
PubMed1999

Tiopronin protects against the nephrotoxicity of cisplatin in the rat.

1. Tiopronin (N-(2-mercaptopropionyl)-glycine) is a drug with a free thiol (sulphydryl) group that is used clinically. We have reported previously that tiopronin protects rat kidney slices in vitro from the nephrotoxic effects of cisplatin and does not reduce the antitumour activity of cisplatin. Tiopronin has been investigated therefore for its protective effects in rats in vivo. 2. The extent of kidney damage was studied 5 days after the administration of cisplatin. A single injection (i.p.) of cisplatin (6 mg/kg; 20 micromol/kg) to female Wistar albino rats caused a sustained decrease in body weight and, after 5 days, plasma urea, creatinine and kidney weight were increased. Tiopronin (2.5 mmol/kg, p.o.) ameliorated cisplatin nephrotoxicity when given 1 h before cisplatin. Tiopronin provided marked protection against cisplatin-induced increases in urea (from 237+/-19 mg to 48+/-23 mg/100 ml; control: 17+/-1) and creatinine (from 6.5+/-0.5 to 1.7+/-0.5 mg/100 ml control: 1.0+/-0.1). Tiopronin did not, prevent the body weight loss caused by cisplatin. In addition, an intraperitoneal dose (1 mmol/kg) of tiopronin afforded similar protection to that of an oral dose. Rats that received an i.p. mixture of cisplatin (6 mg/kg) and tiopronin (65 mg/kg) displayed generally less toxicity, as indicated by a small fall in body weight and smaller increases in urea and creatinine and kidney weight. 3. The results show that tiopronin protects against cisplatin-induced nephrotoxicity. Oral administration of tiopronin may be a clinically useful way to prevent cisplatin nephrotoxicity.

Administration, Oral↗
PubMed1999

Comparative effects of paclitaxel and docetaxel on the metabolism and pharmacokinetics of epirubicin in breast cancer patients.

PURPOSE: To investigate whether paclitaxel and docetaxel influence the pharmacokinetics and metabolism of epirubicin. PATIENTS AND METHODS: We studied the pharmacokinetics and biotransformation patterns of epirubicin in 27 cycles and 20 breast cancer patients. Four patients received epirubicin alone 90 mg/m(2) by intravenous (IV) bolus; eight patients received the same dose of epirubicin followed immediately by paclitaxel 175 mg/m(2) in a 3-hour infusion; the other eight patients received epirubicin 90 mg/m(2) followed immediately by docetaxel 70 mg/m(2) in a 1-hour infusion. Epirubicin and its metabolites, epirubicinol (EOL) and 7-deoxydoxorubicinone (7d-Aone), were identified by high-pressure liquid chromatography. RESULTS: No pharmacokinetic interaction between the parent compound epirubicin and taxanes was detected. Conversely, a significant effect on epirubicin metabolism by both paclitaxel and docetaxel was found. Epirubicin given with paclitaxel or docetaxel yielded areas under the plasma concentration-time curves (AUC) for 7d-Aone 1. 7-fold and 1.9-fold higher (P <.05), respectively, than epirubicin alone. The appearance of two polar metabolites sensitive to glucuronidase was also significantly greater in both taxane groups. Quantitatively different metabolic rates and patterns for EOL were observed in the paclitaxel and docetaxel combinations. The EOL AUC after paclitaxel treatment (1,521 +/- 150 ng/mL*h) was significantly higher (P <.01) than the corresponding values after epirubicin administered either as a single agent (692 +/- 46 ng/mL*h) or in combination with docetaxel (848 +/- 237 ng/mL*h). CONCLUSION: There is no apparent pharmacokinetic interaction between the parent compound epirubicin and paclitaxel or docetaxel. A different pattern of interaction between these taxanes and epirubicin metabolism is clearly evident.

Antibiotics, Antineoplastic↗
PubMed1999

[Contrast media extravasation in upper abdominal injuries: detection with spiral computerized tomography].

PURPOSE: The possibility of detecting contrast agent extravasation (i.e., active hemorrhage) with dynamic conventional Computed Tomography (CT) in patients with abdominal trauma has already been reported in small series. We report our experience in the demonstration of contrast material extravasation using helical CT; we also investigate the diagnostic and clinical value of this finding. MATERIAL AND METHODS: January 1997 to July 1998, we examined 41 consecutive patients with upper abdominal trauma. Twelve patients (29%) had contrast material extravasation. The examinations were performed with a helical unit and volumetric acquisitions (thickness 8-10 mm, pitch 1, reconstruction interval 5-8 mm). The intravenous contrast medium (350 mgI/mL, 130-140 mL) was administered with rapid infusion (2-2.5 mL/s, 40-50 s acquisition delay from bolus starting) and using a power injector. We reviewed the CT studies and clinical records of these 12 patients. Contrast agent extravasation was considered present when this finding, not recognizable on plain scans, showed equal attenuation to or higher attenuation than the vessels within the same level. Moreover we assessed leak site, CT appearance, the direct visualization of the involved vessel, the evidence of other abdominal or extra-abdominal injuries, the CT signs of hypovolemic shock, clinical and surgical data. For comparison, we finally evaluated 50 examinations performed with a conventional CT scanner in subjects with abdominal trauma. RESULTS: Active hemorrhage involved the abdominal wall in 1 case (intercostal artery), the solid organs in 4 (splenic in 2, hepatic in 1, of the middle hepatic vein in 1), the peritoneal cavity in 3 (splenic, midcolic, and gastroduodenal artery in 1 each), the retroperitoneum in 4 (renal pedicle in 2, renal parenchyma in 1, lumbar artery in 1). In all cases the site of contrast extravasation corresponded at surgery to the site of active bleeding. The pattern was localized in 10 cases and diffuse in 2. The involved vessel could be identified in 5 cases while in the other ones the origin could be inferred from the leakage site. Associated injuries of upper abdominal organs were seen in 11 of 12 patients and extra-abdominal trauma in 6. In 4 cases there were CT features of hypovolemia. One patient died during transport to the operating room and another after surgery, while all the others survived. Contrast extravasation was identified in 9 (18%) of the patients examined with a conventional CT unit. CONCLUSIONS: Active contrast material extravasation can be recognized with conventional CT scanners, though it has been considered a rare finding. Helical CT seems to increase the detection rate and especially to boost the radiologist's confidence in this diagnosis. Though active bleeding is identified in severely-injured subjects requiring urgent intervention and may be associated with findings of hypovolemic shock, it should not be considered itself as a negative prognostic factor. Contrast extravasation is due to ongoing hemorrhage and its detection is critical for urgent treatment. Accurate anatomical location permits to choose surgical management or transcatheter embolization and thus decreases time consumption for precise bleeding site identification.

Abdominal Injuries↗
PubMed1999

[Evaluation of the cardiotocographic specificity in antepartum diagnosis].

BACKGROUND: In last years, pregnancies and deliveries carefully monitorized, have led to perinatal mortality decrease. The more common diagnostic method used to point out fetal distress is cardiotocography, which is carried out as a routine screening during pregnancy and labor. The importance of cardiotocography, the limitations of this of measurement of fetal heart rate (FHR) are highlighted: no decrease in neurologic sequelae, positive and/or negative falses, dependence in interpretation on clinicians' experience. Our search aimed at checking the specificity of electronic fetal monitoring of fetal hearth rate at antepartum diagnosis moment. METHODS: 53 pregnant women in the third trimester of gestation period have been studied and the pregnancies results have been compared with specific women CTG trace and results of other diagnostic method (Ultrasound, Velocimetry). RESULTS: Analysing our data we find out that diagnostic methods of fetal distress, at present, are not significative. CONCLUSIONS: To sum up, it is possible to confirm that cardiotocography has a low specificity in fetal distress diagnosis, although it remains the most reliable method. In any case a global evaluation is necessary to monitorize pregnancy by means of clinical screening ordinary used.

Cardiotocography↗
PubMed1999

[Diagnostic imaging and interventional radiology of amebic liver abscesses. Personal experience].

PURPOSE: The diagnostic imaging findings in hepatic amebiasis and the capabilities of percutaneous drainage have already been described but some debate is open on both diagnosis and treatment. We report our experience with ultrasound (US) and Computed Tomography (CT) studies of the hepatic amebic abscess and its management. MATERIAL AND METHODS: During the last 4 years we examined 14 patients with liver abscess: 11 men and 2 women; 13 were Italian and 1 African (25-61 years old, mean 36). All subjects underwent US and contrast-enhanced CT (with a conventional scanner in 12 and a helical unit in 2). The first 4 cases were also submitted to US-guided diagnostic aspiration. Six patients were treated with percutaneous drainage under US guidance using an 8-10 F pig-tail catheter which was removed 4-18 days later (mean 6). RESULTS: The abscesses were always single and uniloculated, in most cases located peripherally in the right lobe. They were large (2-11 cm, mean 7) and had round, oval, or irregular shape in 9, 3, and 2 cases respectively. US generally showed the abscess as an inhomogeneously hypoechoic mass with ill-defined walls. CT demonstrated a homogeneously hypodense collection with a thick peripheral hypodense halo; after contrast agent administration wall attenuation was increased between the edematous halo and the cavity, and an incomplete idosense ring appeared. Biphasic helical acquisitions allowed demonstration of some difference between the two vascular phases and yielded other interesting findings. Drug treatment provided complete abscess resolution in 8 patients, though in 2 it was badly tolerated. In one case no improvement was found and the patient was submitted to percutaneous drainage, which was the treatment of choice in the remaining 5 patients. The treatment was successful in all cases, but 1 patient who discontinued the combined medical therapy developed a heterotopic lesion. CONCLUSION: US and CT findings, though variable and partially different from those previously reported, may be considered sufficient for diagnostic assessment, especially if in the proper clinical and biohumoral setting. Both drug treatment and percutaneous drainage (to be considered for selected cases) are effective in the treatment of this type of abscess.

Adult↗
PubMed1999

[The angiogram sign in pulmonary atelectases studied by spiral computed tomography. Its incidence and semeiologic value].

PURPOSE: We investigated the yield of Helical CT in the study of lung vessels, the incidence of the angiogram sign and its actual value. MATERIAL AND METHODS: July 1997 to December 1998, we studied 30 cases of pulmonary collapse of different origin. We found 15 cases of passive collapse (10 from pleural effusion, 2 from diaphragmatic compression, 2 from traumatic pneumothorax, and 1 from isthmic aortic aneurysm), 12 cases of obstructive collapse (9 from bronchogenic carcinoma, 1 from mucoid obstruction, 1 from hilar lymphadenopathy, and 1 from mediastinal cancer), 2 cases of adhesive collapse and 1 case of round atelectasis. All the examinations were performed with the Helical technique during nonionic iodinated contrast agent injection (bolus, 300-350 mg/mL); we used an automatic injector set at 2-3 mL/s. We studied the images for the angiogram sign, that is hyperdense bands, usually longer than 2 cm, through the collapsed lung, which correspond to normal pulmonary vascular branches. RESULTS: The angiogram sign was found in 95% of passive (14/15) and in 80% of obstructive (10/12) collapses. However in 2 of those we also found some hyperdense spots referable to vessels seen on transverse slices. The angiogram sign was missing in 1 of 2 adhesive collapses because of vascular distortion from irradiation-related fibrosis. The "comet-tail" vascular pattern was seen in round atelectasis. We had no cases of cicatricial collapse. CONCLUSIONS: Thanks to its fast acquisition capabilities, Helical CT well depicts peak vascular enhancement, which permitted identification of the angiogram sign in several pulmonary collapse cases. Thus, this sign becomes even less specific, and just one of the signs of pulmonary consolidation.

Angiography↗
PubMed1999

[Multiphasic spiral computed tomography in hepatocarcinoma. An evaluation following different percutaneous ablative procedures].

PURPOSE: To report our personal experience with helical CT evaluation of hepatocellular carcinoma treated with various percutaneous interventional procedures. We assessed both nodular response and the spectrum of changes within normal parenchyma. MATERIAL AND METHODS: December 1996 to September 1998 we examined with helical CT 41 patients (73 nodules in all) with hepatocellular carcinoma treated with percutaneous ablation therapies: conventional ethanol injection in 18 subjects (31 nodules), one-shot ethanol injection in 3 (8 nodules), radiofrequency thermal ablation in 16 (25 nodules), and combined chemoembolization and ethanol injection in 4 (9 nodules). CT performed was 4-27 days after the last session, acquiring biphasic volumetric images in 14 patients and triphasic volumetric images in 27. A second treatment with subsequent CT study was performed for 28 lesions; 15 underwent 3 serial studies and 6 underwent 4 studies. RESULTS: Compared with pretreatment findings, the diameter was unchanged in 62% of the nodules and increased in 38%. Morphology was unchanged in 63% of the lesions while in 37% a mild deformation toward the needle path or a more regular and round shape was evident. Borders were unchanged in 37% of the cases and modified in 63%, appearing well-defined in 73% and ill-defined in 27%. The necrotic portion had a low attenuation with a nodule-to-parenchyma gradient more evident on delayed than on venous and finally arterial acquisitions; 8% of the lesions were not recognizable on unenhanced scans. Residual viable tissue was identified in 44% of the nodules and quantified as 100% in 1% of all lesions, > 75% in 3%, > 50% in 4%, > 25% in 12%, < 25% in 23%. It was located centrally in 6% of the cases, peripherally in 12%, and eccentrically in 81%, and the shape was crescent in 66% of the cases, oval in 19%, and different in 16%. During the arterial phase the residual tumor appeared hyperdense in 97% of the nodules and isodense in 3%, while during the portal phase it was hyperdense in 22%, isodense in 28% and hypodense in 50%, and during the delayed phase hypodense in 100%. For what concerns the uninvolved parenchyma, lobar atrophy was present in 4% of the nodules, segmental atrophy in 8%, and subsegmental in 16%; caval thrombosis was found in 1 patient, portal thrombosis in 4. Arterioportal fistulas were identified in 5% of the nodules and areas of transient inhomogeneous attenuation in several cases. Subsegmental biliary dilation was detected in 4% of the lesions. CONCLUSION: Multiple-phase helical CT allows optimal depiction of primitive liver nodules treated with percutaneous interventional procedures and has a central role in the assessment of tumor response. Accurate is also the evaluation of changes or complications involving the surrounding parenchyma. Regarding the ablation effect, two typical features can be identified: after total necrosis nodular volume is unchanged or increased, borders are well-defined, and density is low and homogeneous (especially in delayed phases), while after partial necrosis the diameter is not modified, margins are ill-defined, attenuation is less decreased, and peripheral tumor maintains high density in arterial phase and low density in delayed phases. As for the treatment procedure, we found that thermal ablation with radiofrequency and single-session ethanol injection cause more evident alterations within both nodule and hepatic parenchyma, while after multi-session ethanol injection changes are less dramatic and consequently more difficult to assess.

Adult↗