Prostate tissue characterization/classification in 144 patient population using wavelet and higher order spectra features from transrectal ultrasound images.

In this work, we have proposed an on-line computer-aided diagnostic system called "UroImage" that classifies a Transrectal Ultrasound (TRUS) image into cancerous or non-cancerous with the help of non-linear Higher Order Spectra (HOS) features and Discrete Wavelet Transform (DWT) coefficients. The UroImage system consists of an on-line system where five significant features (one DWT-based feature and four HOS-based features) are extracted from the test image. These on-line features are transformed by the classifier parameters obtained using the training dataset to determine the class. We trained and tested six classifiers. The dataset used for evaluation had 144 TRUS images which were split into training and testing sets. Three-fold and ten-fold cross-validation protocols were adopted for training and estimating the accuracy of the classifiers. The ground truth used for training was obtained using the biopsy results. Among the six classifiers, using 10-fold cross-validation technique, Support Vector Machine and Fuzzy Sugeno classifiers presented the best classification accuracy of 97.9% with equally high values for sensitivity, specificity and positive predictive value. Our proposed automated system, which achieved more than 95% values for all the performance measures, can be an adjunct tool to provide an initial diagnosis for the identification of patients with prostate cancer. The technique, however, is limited by the limitations of 2D ultrasound guided biopsy, and we intend to improve our technique by using 3D TRUS images in the future.

MRI and "tenderness guided" transvaginal ultrasonography in the diagnosis of recto-sigmoid endometriosis.

PURPOSE: To compare the diagnostic accuracy of MRI and "tenderness-guided" transvaginal ultrasonography (tg-TVUS) in the identification of recto-sigmoid endometriosis. MATERIALS AND METHODS: Institutional Review Board approval for this study was obtained, and written informed consent was given by all patients. This study is compliant with the STARD (Standards for Reporting of Diagnostic Accuracy) method. Fifty-nine patients (mean age, 33 years; range, 21-44 years) with clinical suspicion of deep pelvic endometriosis were prospectively enrolled. They underwent tg-TVUS and MRI before surgery. The characteristics of the MRI signal were analyzed. Mapping of recto-sigmoid endometriosis was performed and tg-TVUS and MR imaging results were compared with surgical and pathological findings. Sensitivity, specificity, and the positive and negative likelihood ratio (LR+ and LR-) were calculated. Inter-technique concordance was assessed using the Cohen statistic, and receiver operating characteristic (ROC) curves were obtained. Logistic regression analysis was performed. RESULTS: The prevalence of recto-sigmoid endometriosis was 51%. The specificity, sensitivity, and LR+ and LR- were 90%, 73%, 7.089 and 0.297, respectively, for MRI and 86%, 73%, 5.317 and 0.309, respectively, for tg-TVUS. The presence of a high T1 signal spot was an excellent specific finding (100%) but was associated with a low sensitivity (30%). Inter-technique concordance using the Cohen statistic indicated a kappa value of 0.658 (± 0.098 SD). According to the logistic regression equation obtained, the use of both tg-TVUS and MRI allows optimal diagnostic performance. CONCLUSION: MRI and tg-TVUS show similar results in the identification of recto-sigmoid endometriosis. The Cohen kappa value suggests that these methods may have complementary roles in the identification of recto-sigmoid endometriosis, depending on the site affected.

Anatomic variations of arterial liver vascularization: an analysis by using MDCTA.

PURPOSE: The knowledge of celiac trunk vascularization and hepatic arteries' configuration is extremely important in several areas like hepato-biliary pancreatic surgery, as well as in interventional radiological treatment. Our purpose was to evaluate the incidence of anatomic variation of arterial liver vascularization by using MDCTA in a large, homogeneous population. METHODS: Between January 2004 and December 2009, 1,910 patients (1,156 men; mean age, 62.7 years) who underwent MDCT were retrospectively analyzed. Hepatic arterial configuration was classified according to Michels' classification. Image quality was graded according to an ordinal scale. RESULTS: Of the 1,910 examined patients, 281 (15, 67%) were excluded because of sub-optimal image quality. Of the remaining 1,629 patients (986 men; mean age, 61.1 years ± 8 (SD); age range, 19-90 years), anatomic variations were detected in 631 patients (38.73%). CONCLUSIONS: MDCT was useful in analyzing arterial liver configuration and demonstrated the presence of a significant incidence of arterial variants (38.73%) in the examined population.

Learning curve in the detection of ovarian and deep endometriosis by using Magnetic Resonance: comparison with surgical results.

PURPOSE: Determining if Magnetic Resonance Imaging (MRI) accuracy in diagnosing endometriosis is related to radiologist's expertise. METHODS AND MATERIALS: Written informed consent was obtained from all patients. This study is compliant to STARD method. Thirty patients (mean age 34; range 21-45 years) who had undergone MRI study for suspected endometriosis underwent surgery were retrospectively evaluated. MRI at 1.5T was performed with SE and TSE sequences, T1 and T2-weighted with and without fat suppression. Four localizations were analyzed: ovary, uterosacral ligaments (USL), vaginal fornix and Rectum\Sigma\Douglas (R.S.D.). One radiologist evaluated each dataset; sensitivity, specificity, PPV and NPV, accuracy, LR+ and LR- were calculated according to the surgical results (first analysis). Dataset were then re-analyzed 12 months (second analysis) and 24 months (third analysis) later. McNemar test was applied to determine differences between the three analysis. RESULTS: Sensitivity, specificity and accuracy for the ovary at the first analysis were 88.9%, 87% and 88%, at the second 92.6%, 87% and 90% whereas at the third 92.6%, 91.3% and 92%. Sensitivity, specificity and accuracy for the USLs at the first analysis were 62.5%, 76.9% and 70%, at the second 72%, 80.8% and 76% whereas at the third 80%, 84.6% and 82%. Sensitivity, specificity and accuracy for the vaginal fornix at the first analysis were 63.2%, 64.5% and 64%, at the second 73.7%, 77.4% and 76% whereas at the third 73.7%, 83.9% and 80%. Sensitivity, specificity and accuracy for the R.S.D. at the first analysis were 39.1%, 81.5% and 62%, at the second 62.5%, 85.2% and 76% whereas at the third 73.9%, 88.9% and 82%. McNemar test indicated a significant statistical difference in sensitivity in detecting nodules of endometriosis in R.S.D. between first and third analysis (p=0.0215). The mean review time decreased (p=0.0001). CONCLUSIONS: Accuracy of MRI in diagnosing endometriosis increased with radiologist's expertise and the improvement was statistically significant in determining RSD involvement.

Comparison between quantification methods of carotid artery stenosis and computed tomographic angiography.

PURPOSE: The purpose of this study was to compare 3 percentage carotid artery measurement methods (the North American Symptomatic Carotid Endarterectomy Trial [NASCET], the European Carotid Surgery Trial [ECST], and the Carotid Stenosis Index [CSI]) and 1 millimeter method (direct millimeter measurement) to evaluate the difference and correlation between them. MATERIALS AND METHODS: Seven hundred ninety-two patients (591 men; age: mean, 63 years; range, 32-91 years) studied by using a multi-detector row computed tomographic scanner for a total of 1584 carotid arteries were retrospectively analyzed. Each carotid stenosis was measured according to 4 measurement methods (the NASCET, the ECST, the CSI, and the direct millimeter measurement). Carotid arteries with near-occlusion condition were excluded. The Kolmogorov-Smirnov Z test was used to test the normality of continuous variable groups. Comparison of derived ratio-percent methods was performed by using the Bland-Altman plots, and receiver operating characteristic curves were calculated. Correlation coefficients were also calculated by using a nonparametric Spearman correlation. A P < 0.05 was considered to mean statistical significance. RESULTS: Four hundred sixteen carotid arteries were excluded, and in the remaining 1168 ones, a strength correlation according to quadratic regression between the NASCET and ECST methods was observed (Spearman rho coefficient, 0.948; P < 0.0001). An inverse correlation according to linear regression was observed between the NASCET and the direct millimeter measurement (Spearman rho coefficient, -0.972; P < 0.0001); the CSI shows a quadratic regression with the NASCET, a linear regression with the ECST, and an inverse linear regression with the direct millimeter measurement (Spearman rho coefficient, 0.946, 0.932, and -0.939 respectively). The cutoff values for 50% and 70% NASCET stenosis were 2.36 and 1.51, respectively. CONCLUSIONS: Our study results indicate that the direct millimeter measurement of stenosis, by using appropriate equations, can reliably predict NASCET-, ECST-, and CSI-type percent stenoses. The use of direct millimeter measurement may remove the pitfalls and the discrepancies deriving from the use of different ratio-percent methods.

Agreement and reproducibility in identification of endometriosis using magnetic resonance imaging.

BACKGROUND: Magnetic resonance imaging (MRI) is a promising technique in the study of endometriosis, allowing a complete mapping of lesions before surgery. However, the value of MRI in the diagnosis of endometriosis in the bladder, in superficial peritoneal lesions, and in ovarian foci and uterosacral ligaments is still under debate. PURPOSE: To assess inter- and intra-observer agreement in the evaluation of endometriosis in different anatomical locations using MRI. MATERIAL AND METHODS: From June 2006 to February 2008, 83 female patients (mean age 39, range 19-49 years) who had undergone MRI examination for suspected endometriosis were evaluated by two radiologists. MRI at 1.5 Tesla was performed with SE and TSE sequences, T1- and T2-weighted with and without fat suppression. Each examination was completed with gadolinium administration. Each dataset was independently evaluated by the radiologists for the presence or absence of endometriosis. The location (ovaries, uterosacral ligaments (USLs), pouch of Douglas, vagina, rectosigmoid, rectovaginal septum, and bladder) of suspected lesions was recorded. Cohen kappa statistical analysis was performed to calculate agreement between measurements. After 2 months the data were analyzed again by the two observers to assess intra-observer agreement. RESULTS: Of the 83 MRI examinations performed, 12 patients demonstrated no evidence of endometriosis. In the remaining 71 studies, 157 endometriotic lesions ranging in size from 0.4 to 6.2 cm were detected. Of the 157 lesions, 53 (33.75% incidence) were smaller than 1 cm. In the ovaries, the inter-observer agreement was 92.77% and the kappa value was 0.802 (95% CI, 0.695-0.91). In the bladder the inter-observer agreement was 96.39% and the kappa value was 0.553 (95% CI 0.056-1). In the USLs the inter-observer agreement was 90.96% and the kappa value 0.583 (95% CI, 0.381-0.784). In the rectovaginal septum the inter-observer agreement was 94.58% and the kappa value 0.739 (95% CI, 0.572-0.905). In the rectovaginal pouch the inter-observer agreement was 88.55% and the kappa value 0.608 (95% CI, 0.443-0.774). In the vaginal fornix the inter-observer agreement was 94.58% and the kappa value 0.726 (95% CI, 0.552-0.901). In the rectosigmoid the inter-observer agreement was 89.76% and the kappa value 0.589 (95% CI, 0.389-0.768). CONCLUSION: The results of our study indicate that MRI has a high inter- and intra-observer agreement in the identification of endometriosis located in the ovary, rectosigmoid, and rectovaginal septum, whereas the agreement is suboptimal for the identification of endometriosis located in the USLs.

Angio computed tomography preoperative evaluation for anterolateral thigh flap harvesting.

The vascular anatomy of the anterolateral thigh flap (ALTF) has many possible variations, and none of the currently used mapping techniques (eg, Echo Color Doppler) gives a thorough knowledge of all details. Among the last generation of angiographic diagnostic techniques, multi detector computed tomography, popularly known as Angio CT, has emerged as an outstanding noninvasive operator independent option, and has been described for deep inferior epigastric perforator and pedicled transverse rectus abdominis muscle planning. This study was conducted to evaluate its usefulness prior to ALTF harvesting.Nine consecutive patients were considered for oral or lower extremity reconstruction with the ALTF. After written informed consent was obtained from all patients, a preoperative Angio-CT study was performed for surgical planning. Accurate identification of septocutaneous or musculocutaneous perforator vessels was achieved and their location, course, and anatomic variations were reported and influenced surgery. Angio CT allows a complete vascular study of the donor area of the ALTF and evaluation of the best perforator vessels before surgery allows surgeons to get an ideal planning of the flap. This imaging method is currently proposed to every patient undergoing ALT flap reconstruction.

Mature and immature ovarian teratomas: CT, US and MR imaging characteristics.

Ovarian teratomas (OTs) are the most common germ cell neoplasm. They include mature cystic teratomas, monodermal teratomas (neural tumors, struma ovarii, carcinoid tumors) and immature teratomas. Teratomas are the most common benign ovarian neoplasms in women less than 45 years old. OTs are usually characterized by ultrasound (US) and magnetic resonance (MR) whereas they are usually an incidental finding on CT. The purpose of this paper is to review the most common types of teratomas and to describe CT, US and MR imaging features of the various types of mature and immature OTs.

Agreement between multidetector-row CT angiography and ultrasound echo-color Doppler in the evaluation of carotid artery stenosis.

PURPOSE: Stroke is a leading cause of severe disability in the western world. A correct diagnostic procedure to stratify risk is necessary in order to rapidly plan the most efficient therapy. The purpose of this work was to evaluate the agreement between ultrasound echo-color Doppler (US-ECD) and multidetector-row CT angiography (MDCTA) in determining the degree of carotid stenosis. METHODS AND MATERIALS: From January 2004 to February 2007, 187 patients who had previously undergone both US-ECD and MDCTA were studied retrospectively. For each patient, stenosis degree was measured by applying the North American Symptomatic Carotid Endarterectomy Trial criteria. Data derived from MDCTA and US-ECD were then compared to calculate the inter-technique variability by using Cohen kappa statistics. For all plaque types (fatty, mixed and calcified), inter-technique variability was assessed. The Wilcoxon signed-rank test was used to highlight differences between the procedures, and scatterplots were also calculated. As a gold standard, reference surgical comparisons were performed in 50 patients. RESULTS: The percentage of observed agreements in the evaluation of stenosis degree was 72.19% with a kappa value of 0.659 (95% confidence interval: 0.604-0.715) and a weighted kappa of 0.789. After the evaluating stenosis degree in fatty, mixed and calcified plaques, the percentages of observed agreements were 79.31, 74.58 and 64.29%, respectively, with kappa values of 0.738, 0.691 and 0.565. CONCLUSION: A good agreement between US-ECD and MDCTA in the evaluation of stenosis degree was observed, together with a remarkable difference between the 2 techniques in the assessment both of calcified plaques and of plaques showing a predominant calcific component.

Computed tomographic imaging findings of bowel ischemia.

LEARNING OBJECTIVES: Learning objectives of this paper are to review and to summarize the pathogenesis of bowel ischemia and to describe its clinical, pathological, and radiological manifestations. BACKGROUND: Bowel ischemia is a common disorder produced by several causes, and it shows various clinical presentations connected with an high mortality. With the increase in average life expectancy, bowel ischemia represents one of the most threatening abdominal conditions in elderly patients. In the last decade, computed tomography has tremendously altered the diagnostic approach to bowel ischemia also influencing the therapeutic approach in the current practice. IMAGING FINDINGS: Computed tomographic imaging findings include bowel wall thickening, portal venous gas, intramural pneumatosis, engorgement of mesenteric veins, loss or increase of bowel wall enhancement, and infarction of other abdominal organs. CONCLUSIONS: Bowel ischemia shows a broad spectrum of radiological manifestations, and regardless of the primary causes, it produces similar radiological features. Bowel ischemia may simulate cancer or inflammatory conditions; so it is a mandatory tight integration between radiological and clinical signs.

Carotid artery wall thickness and ischemic symptoms: evaluation using multi-detector-row CT angiography.

The purpose of this study was to determine if carotid artery wall thickness (CAWT) studied by using multi-detector-row CT angiography (MDCTA) can be considered an effective parameter predictive of increased risk of stroke. A total of 217 patients were retrospectively studied by using MDCTA. In all patients CAWT was measured with an internal digital caliper. Continuous data were described as the mean value +/- standard deviation (SD), and they were compared with Student's t-test. Scatter plots to determine interobserver agreement were performed, and correlation coefficient was calculated with Pearson statistics. A P value <0.05 was considered to mean statistical significance. Measurements of the distal common CAWT ranged from 0.5 to 1.6 mm. In the patient group without stroke, average CAWT was 0.82 mm (0.22 SD), whereas in patient group with stroke it was 1.096 mm (0.21 SD). CAWT in patients without stroke showed statistical difference (P < 0.0001) when compared to patients with stroke. By using a threshold of 1 mm, an important statistical association between thick CAWT and stroke was found (P < 0.0001). In fact, patients with > or = 1 mm CAWT had stroke with an odds ratio of 8.16 when compared with patients with <1 mm CAWT. Resulting data suggested that an increased CAWT is an indicator for risk of stroke. This parameter should be considered in addition to other well-known risk factors such as diabetes, hypertension, smoking, and dyslipidemia.

Preoperative Angio-CT preliminary study of the TRAM flap after selective vascular delay.

BACKGROUND: The pedicled TRAM (pTRAM) flap is one of the best options for autologous breast reconstruction, but vascular complications reported in the standard versions are about 30%. To reduce complication rate, especially in high-risk patients, surgical delay has been suggested. Individual precise preoperative location and evaluation of perforating vessels and of variations of the diameter of the deep superior epigastric artery (DSEA) are highly desirable for improving surgical strategy. Previous reports using color duplex scanning, although generally confirming the validity of the delay maneuver, have showed several pitfalls. The aim of this report was to demonstrate the usefulness of multidetector computed tomography angiography (MDCTA) for preoperative planning in patients undergoing pTRAM flap breast reconstruction after selective vascular delay. METHODS: Three patients were considered for breast reconstruction with the pTRAM flap. An MDCTA was performed before and after selective delay to locate the muscle perforators and to show increase in DSEA diameter. Axial images, multiplanar reconstruction, and 3D volume images were analyzed. RESULTS: Accurate identification of the main perforators was achieved. Location, course, and anatomic variations of DSEA were reported. The average increase in diameter of the DSEA was 29.3%. CONCLUSION: Preoperative planning of pTRAM flap with MDCTA allows surgeons to visualize and locate the dominant perforators and to select the best DSEA. Consequently, the choice between the homolateral or contralateral rectus muscle is facilitated. The high sensitivity and specificity and the ease of interpreting data have made MDCTA a highly promising diagnostic tool for planning a pTRAM flap.

Computer-aided detection of pulmonary nodules in computed tomography: analysis and review of the literature.

PURPOSE: To evaluate diagnostic sensitivity of the pulmonary nodules computer-aided detection (CAD) in computed tomography. To analyze parameters that modify CAD performance. We made a critical analysis of the literature, and we described CAD sensitivity. Moreover, we compared CAD and CAD plus radiologist sensitivity in detection of pulmonary nodules, and we compared different acquisition techniques (thin slice vs thick slice and low dose vs normal dose). MATERIALS AND METHODS: We used as major data sources the medical literature database of PubMed and MEDLINE, where we searched for articles in English language published from January 2001 to November 2006. We included studies that used spiral or multidetector row CT for CAD. RESULTS: Twenty studies met the inclusion criteria containing a total of more than 827 patients and 2717 pulmonary nodules detected by CAD. We observed an overall sensitivity of 79% for the CAD and of 92% for CAD plus radiologist; CAD sensitivity was 80% and 74% for thin slice and thick slice protocols, respectively. CONCLUSIONS: Results of our study suggest that CAD technique is an accurate tool in detection of pulmonary nodules, by working as useful second look for the physician. Sensitivity becomes higher by using it together with radiologist. Actually, the main limitation about the use of CAD to be solved is represented by the persistent high false-positive rate.

Stop Flow in abdominal and pelvic cancer relapses.

To determinate MTD, DLT and safe doses for phase II study, a dose finding study with Mitomycin and Adriamycin Stop-Flow administration was carried out. A phase II study focused on resectability of pelvic colorectal relapses is in progress. From November 1995, 84 pts, 52 male and 32 female (94 treatments), with advanced not resectable abdominal (14 pts) or pelvic (70 pts) relapses, and resistant to previous systemic chemotherapy, were enrolled in the study. 46 pts entered the phase I-early phase II study, while subsequently 38 pts were recruited in ongoing phase II study. Safe dose were: MMC 20 mg/mq and ADM 75 mg/mq. The phase II study focused on colorectal relapses registered very promising responses: 90% pain control, 1 pCR and 26 PR / 63 (OR 43%), 8 NC (13%) 9/27 responder patients (33%) obtained a complete resectability of colorectal relapses. Stop-Flow is a safe and feasible technique very useful as a palliation treatment.

Short-term variations in bone remodeling markers of an oral contraception formulation containing 3 mg of drospirenone plus 30 microg of ethinyl estradiol: observational study in young postadolescent women.

The clinical study of treated subjects and nontreated controls was made in healthy eumenorrheic young postadolescent women volunteers in the Department of Obstetrics and Gynaecology at Cagliari University, to investigate whether an oral contraceptive (OC) containing drospirenone (3 mg) plus ethinyl estradiol (30 microg) (DRSP+EE) can affect bone metabolism. Control group (n = 26) and OC group (n = 28) women did not differ in age, body mass index, waist-to-hip ratio and main outcome measures [urinary levels of deoxypyridinoline and pyridinoline, serum levels of osteocalcin, bone specific alkaline phosphatase (bSAP), total testosterone (total-T), sex hormone-binding globulin (SHBG), progesterone and bone mineral density (BMD) at the heel]. The control group was studied at the luteal phase (LP) during both the first and the sixth menstrual cycle; the OC group was studied during the first cycle at the LP, and on days 16-18 of the sixth cycle of DRSP+EE treatment. At the sixth cycle, in the control group, the main outcome measures did not change compared to baseline. In the OC group, deoxypyridinoline, pyridinoline, osteocalcin, bSAP, total-T and progesterone levels were reduced, whereas SHBG levels were increased. The BMD was unchanged compared to baseline. The results suggest that 6-month DRSP+EE treatment decreases bone turnover.

No recurrence of mature ovarian teratomas after laparoscopic cystectomy.

Recurrence of ovarian teratomas was evaluated in a randomised trial to determine whether laparoscopic cystectomy had the same efficacy as laparotomy. Forty premenopausal non-pregnant women with a unilateral teratoma no larger than 10 cm were randomised to laparoscopy or laparotomy. Post-operative pain, duration of stay in hospital and duration of convalescence were compared. Women were reviewed every six months for five years. A higher proportion had milder pain, faster hospital discharge and faster recovery following laparoscopy than laparotomy. There were no recurrences of teratomas in both arms of the study, suggesting that laparoscopy has the same efficacy as laparotomy.