"CADEAT": considerations on the use of CAD (computer-aided diagnosis) in mammography.

Computer-aided diagnosis (CAD) has been extensively reported to increase sensitivity by about 10% when added to a single reading while increasing recall rate by 12%, and its current use can be safely recommended in clinical practice. CAD has been suggested as a possible alternative to conventional double reading in screening. Uncontrolled comparison is consistent and suggests that CAD is comparable to double reading in incremental cancer detection rate (CAD +10.6%, double reading +9.1%) and possibly better in recall rate (CAD +12.5%, double reading +28.8%). However, controlled studies comparing single reading + CAD to conventional double reading are not consistent and on average suggest a lower cancer detection rate (-5.1%) and a lower recall rate (-9.8%) for CAD. Scientific evidence is not sufficient for a safe recommendation of single reading + CAD as a current alternative to conventional double reading.

Virtual colonoscopy.

Computed axial colonography, usually called virtual colonoscopy, is a new diagnostic method potentially useful for investigating polyps and tumors of the colon and rectum. It uses spiral axial tomography data to build up images similar to those given by conventional colonoscopy, offering advantages in that it causes no adverse reactions, and is accepted well by patients, who do not need to be sedated. Reports to date show its sensitivity and specificity vary in identifying polyps in the colon, and there are still many problems with the new method, such as its cost, its learning curve, the identification of flat lesions, and detection of extracolonic abnormalities. There is a pressing need to establish the accuracy and cost-effectiveness of virtual colonoscopy as a screening method for colorectal tumors, and for post-polypectomy surveillance.

[Pulse inversion ultrasonography with ultrasonography contrast media (levovist) in the evaluation of hepatic metastasis]. / Ecografia con tecnica di inversione di impulso e mezzo di contrasto ecografico (Levovist) nella valutazione delle metastasi epatiche.

PURPOSE: To evaluate if Pulse Inversion Harmonic Imaging with contrast agent injection (Levovist) is able to determine an increase of echogenicity in normal hepatic parenchyma, and to compare its capability to detect metastatic focal lesions with that of standard US and spiral CT. To define and standardize the technical and methodological aspects of this new technique. MATERIAL AND METHODS: A selected group of 72 patients (42 males and 30 females) with clinical and instrumental suspect of hepatic metastatic lesions was included in the prospective study. Each patient was examined by conventional ultrasound (US), Pulse Inversion Harmonic Imaging (PI) and spiral-CT (spCT). US examination was performed using an HDI 5000 (ATL, Bothell, USA) equipped with a broadband probe (5.0-2.0 MHz). 2.5 g Levovist (Schering AG-Berlin) was administered intravenously, at concentration of 300 mg/ml and a flow rate of 7 ml/min. Video clips obtained with the acquired images before and after contrast medium administration were transferred to a magnet optic disk unit. Examinations were evaluated by an experienced radiologist blindly on a workstation that allowed a qualitative-quantitative analysis. SpCT images were evaluated separately by another experienced radiologist. US images were evaluated qualitatively (number of lesions, site of lesion, diameter of the smallest lesion detectable) and quantitatively (increase in parenchymal echogenicity 20", 40", 60" and 5' after the injection of contrast agent). RESULTS: In all cases examined, the echogenicity of normal hepatic parenchyma increased after contrast agent administration, reaching a peak of about 250% (1DS) at 60 s and a decreasing gradually in 5 minutes. Conventional US detected 195 focal lesions, CT 231, and US with pulse inversion technique and contrast agent (US-PI) 287. Mean differences among the number of lesions detected by the different techniques per each patient were also calculated. Wilcoxon Signed Rank Test showed a statistically significant difference between US-PI and US (p < .0001), CT and US (p = .0052) and US-PI and CT (p = .0121). US-PI detected the smallest lesions, which went undetected by the CT and conventional US examinations. DISCUSSION AND CONCLUSIONS: In 10 cases (14.3%) contrast enhanced US-PI demonstrated the presence of a number of lesions greater than 5 (diffuse metastatization and inoperability) in comparison to that detected by spCT). The greater echogenicity of normal hepatic parenchyma using pulse inversion technique after Levovist infusion allowed to better demonstrate hepatic metastases. This technique showed a higher identification rate of small lesions in comparison to basal examination and to spiral CT. Contrast enhanced US-PI demonstrated a remarkable increase in echogenicity of hepatic parenchyma in portal phase. The technique significantly improves the detection of focal lesions allowing visualization of smaller lesions compared to CT and US. These results indicate that the technique could be used in the staging of liver metastasis. However, large multicentric trials are required to validate US-PI and better define its role in the work-up of patients with neoplastic disorder.

Computed tomographic colonography and conventional colonoscopy for colon diseases: a prospective, blinded study.

OBJECTIVES: Computed tomographic (CT) colonography or virtual colonoscopy is a new diagnostic method for the colon and rectum, developed on the basis of spiral computed axial tomography and employing virtual reality technology. The aim of this study was to determine the sensitivity, specificity, and diagnostic accuracy of CT colonography compared with colonoscopy in a prospective, blinded study in one single institution in Italy. METHODS: Ninety-nine patients randomly selected among those attending the open-access endoscopy unit for diagnostic colonoscopy underwent colonoscopy and spiral CT. The images obtained were transmitted to generate the virtual colonoscopy pictures. A supervisor compared the results with the findings of conventional colonoscopy. RESULTS: CT colonography diagnosed seven of eight tumors, one being missed because the patient had been inadequately prepared. In 28 patients, CT colonography identified 26 polyps of 45 (57.8% sensitivity, 92.6% specificity, 86.7% positive predictive value), regardless of their size. The sensitivity in detecting colonic polyps was 31.8% (7/22) in the first 25 cases and 91.6% (11/12) in the last 20 patients. CT colonography missed one flat adenoma, some angioectasias and colonic lesions because of portal hypertension in one patient, Crohn's disease ulcers in two patients, and ulcerative colitis lesions in three. CONCLUSIONS: CT colonography shows poor sensitivity for identifying colonic polyps and does not always detect neoplastic lesions. Flat lesions are impossible to see by this method.

A new Doppler signal enhancing agent for flow assessment in breast lesions.

OBJECTIVE: To determine the diagnostic performance of SonoVue (Bracco) in the enhancement of Doppler signals in breast lesions and in the improvement of diagnostic accuracy. METHODS: This multicenter study included 220 patients undergoing investigations of parenchymal lesions, 40 of which had breast tumors. After a baseline Doppler examination, intravenous doses of 0.3, 0.6, 1.2 and 2.4 ml SonoVue were injected. Doppler signal quality before and after injection was compared. Off-site assessment of the global quality of Doppler signal and duration of clinical useful enhancement, as well as off-site and on-site evaluation of quality of color and spectral Doppler, were performed. On-site evaluation of diagnostic accuracy was also carried out. Safety assessments included monitoring of adverse events up to 24 h following the last injection of SonoVue. RESULTS: On-site evaluations: baseline Doppler was conclusive in only 4/21 carcinomas and in 2/17 benign lesions. Enhanced Doppler improved differential diagnosis in 20/21 carcinomas and in 9/12 benign lesions. Time to color enhancement was 0.55 min for the lowest and 0.35 min for the highest dose. The total duration of enhancement was 3.47 min for the lowest and 5.62 min for the highest dose, respectively. Off-site assessment: SonoVue improved the quality of Doppler blood flow information both in parenchymal and focal lesions. Statistically significant changes from baseline in global quality of Doppler investigations were observed at all four SonoVue doses (P<0.05). The duration of clinically useful signal enhancement increased with doses and a significant dose relationship was obtained (P<0.001). Mild adverse events were observed in two patients only. CONCLUSION: The results obtained from this study, following both off-site and on-site assessment, demonstrate that the administration of SonoVue to patients with focal breast lesions provides significant improvement over the baseline of Doppler signal quality and a clinically useful duration of signal enhancement, related to the dose. SonoVue was shown to be a safe and well-tolerated compound.

[Mammography changes associated with hormone replacement therapy in post-menopausal patients]. / Le modificazioni mammografiche nella terapia ormonale sostitutiva nelle pazienti dopo la menopausa.

Hormone replacement therapy (HRT) in post-menopausal or ovariectomized women reduces mortality due to cardiovascular diseases, lowers morbidity due to osteoporosis and improves vasovagal symptoms. Long-term therapy, however, increase the risk of side-effects. HRT may decrease mammographic sensitivity, markedly increasing glandular density. Enlargement of pre-existing cysts and fibroadenomas has also been reported after HRT. The correlation between HRT and breast cancer is highly controversial. We examined 650 women: 550 of them (84.6%) received HRT (157 estrogens and 393 estrogens-progestins) and 100 (15.4%) refused treatment and were thus considered as a control group. All patients underwent mammography and DEXA before HRT and, during treatment, were followed-up yearly with mammography, often combined with US, and DEXA. Fisher's test was used for data analysis (confidence interval: 95%). The statistical analysis showed a significant difference between the HRT group and the control group only for the lumbar spine. Mammographic changes (Tab. II) were shown in 150 of 550 HRT patients. Increased breast density was the most frequent finding. Benign lesions arising de novo or increasing in size and/or number were observed in 41 of 150 patients (27.3%) in the HRT group, where 3 breast carcinomas were detected, versus 1 breast cancer only in the control group. HRT had a marked positive effect on bone mineral content (BMC) at 2 years' follow-up, but it remains debated if it reduces breast cancer risk. In conclusion, our results indicate that a yearly mammography is mandatory in long-term HRT subjects and US may be also needed in particularly dense breasts.

Shape of the human corpus callosum in childhood. Elliptic Fourier analysis on midsagittal magnetic resonance scans.

RATIONALE AND OBJECTIVES: The authors previously investigated the midsagittal magnetic resonance images of neurologically intact adults, and analyzed the shape of corpus callosum from a mathematic standpoint. Significant effects of age were demonstrated, without significant sex differences. In the current study, the same mathematic method was applied to analyze the sex and age shape differences of the human corpus callosum in childhood. METHODS: On the midsagittal magnetic resonance images of 84 neurologically intact children (39 boys, 45 girls, aged 4 months to 15 years) the outline of the corpus callosum was identified. Its shape was quantified using elliptic Fourier analysis, which allows for global evaluation of the shape of organs identified by their outlines independently from size, spatial orientation, and relationship to reference planes. Subjects were grouped by sex and age. RESULTS: The shape of the corpus callosum within age and sex classes in childhood was more homogeneous than in adulthood. A significant effect of age was demonstrated by the analysis of variance; however, no significant sex differences were found. CONCLUSIONS: Corpus callosum shape in midsagittal magnetic resonance images was strongly influenced by central nervous system development and aging, but the influence of sex was not sufficient to be detected by current standard magnetic resonance imaging technology, and by the available sample sizes. The current investigation supplies data on the normal callosal shape in the first two decades of life, thus completing previous analysis.

Shape of the human corpus callosum. Elliptic Fourier analysis on midsagittal magnetic resonance scans.

RATIONALE AND OBJECTIVES: Sex, age, or functional-asymmetry-related variations in the size and shape characteristics of the midsagittal magnetic resonance (MR) image of the human corpus callosum (CC) have been widely investigated in the last 10 years, with conflicting results. In the current study, the authors attempted to analyze the sex- and age-related shape differences of the human CC in a large sample of adult subjects from a mathematical standpoint. METHODS: On the midsagittal MR images of 143 neurologically intact adults (75 women, 68 men, 21 to 81 years of age) the outline of the CC was identified. The shape of the CC was quantified using elliptic Fourier analysis, which allows for a global evaluation of the shape of organs identified by their outlines independent of their size, spatial orientation, and relation to reference planes. Subjects were grouped by sex and age. RESULTS: The shape of the human CC within age and sex class was highly variable. The analysis of variance showed a significant effect of age; however no significant sex differences could be demonstrated. CONCLUSIONS: Larger sample sizes are required to definitively assess the normal shape variations in human CC. The method developed also could be applied to the comparison of healthy and diseased individuals.

Variation in hemostatic parameters after intra-arterial and intravenous administration of iodinated contrast media.

RATIONALE AND OBJECTIVES: A few case reports have suggested a possible thrombogenic effect of nonionic contrast media. In vitro investigations have lead to conflicting results. The authors performed three ex vivo studies to evaluate the influence of an ionic, ioxaglate, and a nonionic, iopamidol, low-osmolality contrast medium on a series of clotting and fibrinolytic parameters, after intravenous or intra-arterial administration, during routine diagnostic procedures. METHODS: In the first study, iopamidol was given to 20 consecutive patients through an arterial catheter for digital subtraction arteriography (DSA). In the second study, iopamidol was compared with ioxaglate. The media were randomly and blindly administered intravenously to 21 consecutive patients undergoing brain computed tomography (CT). Finally, ioxaglate was administered intra-arterially to 20 consecutive patients, in a situation comparable with that of the first study. RESULTS: In the first study, a weak anticoagulant effect and an activation of fibrinolysis were found, associated with indirect markers of thrombin generation, such as increased plasma levels of fibrinopeptide A (FpA) and thrombin-antithrombin III complexes (TAT). In the second study, no significant changes were seen with either contrast medium, for thrombin or fibrinolysis activation parameters. In the third study, the intra-arterially administered contrast medium elicited a marked increase of FpA and TAT, together with an anticoagulant effect. CONCLUSION: Both ionic and nonionic contrast media are able to interfere with the clotting/fibrinolytic system in the general circulation when they are administered to patients at the usual dosages. Ioxaglate shows more marked anticoagulant and thrombin-generating effects than iopamidol. The procedure (ie, arterial catheter versus intravenous infusion) seems to be more important than the category of contrast medium in conditioning the magnitude of these effects.

[The role of color Doppler echography in the diagnosis of breast tumors]. / Il ruolo dell'eco Color-Doppler nella diagnostica dei tumori della mammella.

The authors discuss the results from a series of 45 patients with breast lumps. All patients were studied by means of mammography, sonography, color Doppler US, and biopsy. Abnormal Doppler signal was observed in 94% of the patients with breast cancer. However, this finding is not specific because it can be occasionally found in benign lesions too. The use of color Doppler US is suggested in those cases where neither US nor mammography is conclusive.

[A comparative evaluation of the centering precision performed with 2 different stereotaxic instruments in nonpalpable breast lesions]. / Valutazione comparativa della precisione nella centratura di lesioni mammarie non palpabili eseguita con due differenti apparecchi stereotassici.

Two different instruments for nonpalpable breast lesion localization, with different patient position (prone and sitting), were evaluated in precision performances by measuring the mean needle deviation on X and Y axes in 150 and 100 examinations, respectively. Both instruments yielded precise information: some drawbacks were observed with the stereotaxic instrument fitted to the plain mammographic unit, due to imperfect fixation in the sitting position of the patient. The development of special seats could obviate the problem, thus allowing a further improvement in the performance of this kind of instruments.

[Role of echography in the diagnosis of ovarian tumors]. / Ruolo dell'ecografia nella diagnosi dei tumori ovarici.

The role of sonography is evaluated in the diagnosis of ovarian tumors. Real-time US proves more sensitive than gynecological examination in the diagnosis of ovarian diseases. As yet, however, no correlation has been found between histological findings and US appearance. An accurate review of the relative literature and of our results lead us to the conclusion that sonography does not significantly affect the early diagnosis of ovarian tumors.

[Urography with non-ionic contrast media. Multicenter experience on the optimization of the technic]. / Urografia con mezzi di contrasto non ionici. Esperienza multicentrica sulla ottimizzazione della tecnica.

The authors report the results of a multicentric experience based on 1200 urograms performed with nonionic contrast medium. The global diagnostic reliability is evaluated, together with the specific reliability for kidneys, ureters, and bladder, according to the various pathologies. The eventual need of radiographs of completion is showed. In searching for an optimization of the technique for nonionic contrast medium, a panoramic radiograph performed 10' after the end of the injection is pointed out as the key-moment of the test, being extremely rich in information, so as to help defining the most appropriate technique to continue the examination. For its excellent tolerability and high reliability, the nonionic contrast medium is recommended also in routine IVP, not only in risk patients.

[CT x-ray in recurrences of lumbar disk herniation. Usefulness of the examination with contrast enhancement]. / La TC nelle recidive di ernia discale lombare. Utilità dell'esame con contrast enhancement.

The CT is an important and valuable instrument in the study of the postoperative lumbar spine, in the patients which presented persistent clinical manifestation. In this report the technique with contrast enhancement is outlined, the criteria for its interpretations are presented, and its advantages and limitations are reviewed; pitfalls in technique interpretation are stressed. Two hundred and fifty patients are referred to the CT without and with i.v. contrast medium for this diagnostic request: scar or herniation at surgery level.