Search results for "Image processing"
showing 10 items of 3285 documents
Dynamic contrast-enhanced myocardial perfusion imaging using saturation-prepared TrueFISP.
2002
Purpose To develop and test a saturation-recovery TrueFISP (SR-TrueFISP) pulse sequence for first-pass myocardial perfusion imaging. Materials and Methods First-pass magnetic resonance imaging (MRI) of Gd-DTPA (2 mL) kinetics in the heart was performed using an SR-TrueFISP pulse sequence (TR/TE/α = 2.6 msec/1.4 msec/55°) with saturation preparation TD = 30 msec before the TrueFISP readout. Measurements were also performed with a conventional saturation-recovery TurboFLASH (SRTF) pulse sequence for comparison. Results SR-TrueFISP images were of excellent quality and demonstrated contrast agent wash-in more clearly than SRTF images. The signal increase in myocardium was higher in SR-TrueFISP …
Congenital Müllerian anomalies: diagnostic accuracy of three-dimensional ultrasound
1996
Objective To determine whether it is possible to identify and diagnose accurately Mullerian anomalies with three-dimensional (3-D) ultrasound (US). Design Controlled blinded clinical study. Setting Normal human volunteers undergoing infertility evaluation in a university hospital. Patients Forty-two patients who underwent laparoscopy and hysterosalpingography as part of their work up for infertility and were found to have either a normal uterus (30 patients) or a Mullerian abnormality (12 patients) consented to be evaluated with 3-D US by sonographers who were unaware of their infertility history or of their laparoscopy and hysterosalpingography diagnoses. Interventions Transvaginal 3-D US …
Subtemporal Keyhole Approach to the Suprasellar and Petroclival Region: Microanatomic Considerations and Clinical Application
1997
OBJECTIVE: To minimize surgical invasiveness, the keyhole concept is applied to the subtemporal approach. METHODS: Anatomic features were studied in 14 sides of adult cadaver heads, and the technique was used in 162 interventions. Although most of the lesions treated were 3 cm in size or smaller, larger lesions were also treated using this technique. In some cases, if needed, an endoscope-assisted microsurgical technique was used. RESULTS: The cadaveric study provided intimate experience with the microsurgical anatomy of the approach. The 162 consecutive patients who were operated on harbored various types of lesions; the most recent 43 consecutive interventions were investigated in detail.…
Middle patellar tendon to posterior cruciate ligament (PT–PCL) and normalized PT–PCL: New magnetic resonance indices for tibial tubercle position in …
2018
BACKGROUND To demonstrate whether the distance between the middle point of the patellar tendon and posterior cruciate ligament (PT-PCL) calculated on a single axial MR image could be an alternative measure to tibial tubercle-PCL (TT-PCL) distance for TT lateralization without the need of imaging processing. To show that normalization of PT-PCL (nPT-PCL) against the maximum diameter of the tibial plateau may help to identify patients with patellar instability (PI). METHODS MR scans of 30 patients (13 females, age 32 ± 13 years) with known PI and 60 patients (31 females, age 39 ± 19 years) with no history of PI were reviewed. Two operators calculated TT-PCL, and PT-PCL nPT-PCL. Intraclass cor…
MAGIC-5: an Italian mammographic database of digitised images for research
2008
The implementation of a database of digitised mammograms is discussed. The digitised images were collected beginning in 1999 by a community of physicists in collaboration with radiologists in several Italian hospitals as a first step in developing and implementing a computer-aided detection (CAD) system. All 3,369 mammograms were collected from 967 patients and classified according to lesion type and morphology, breast tissue and pathology type. A dedicated graphical user interface was developed to visualise and process mammograms to support the medical diagnosis directly on a high-resolution screen. The database has been the starting point for developing other medical imaging applications,…
Comparison of Histochemical Stainings in Evaluation of Liver Fibrosis and Correlation with Transient Elastography in Chronic Hepatitis.
2015
Background and Aim. The best staining to evaluate liver fibrosis in liver hepatitis is still a debated topic. This study aimed to compare Masson’s trichrome (MT), Sirius Red (SR), and orcein stainings in evaluating liver fibrosis in chronic HCV hepatitis (CHC) with semiquantitative and quantitative methods (Collagen Proportionate Area (CPA) by Digital Image Analysis (DIA)) and correlate them with transient elastography (TE).Methods. Liver stiffness evaluation of 111 consecutive patients with CHC was performed by TE. Semiquantitative staging by Metavir score system and CPA by DIA were assessed on liver biopsy stained with MT, SR, and orcein.Results. MT, SR, and orcein staining showed concord…
Digital image analysis of collagen assessment of progression of fibrosis in recurrent HCV after liver transplantation
2013
BACKGROUND & AIMS: Histological assessment of fibrosis progression is currently performed by staging systems which are not continuous quantitative measurements. We aimed at assessing a quantitative measurement of fibrosis collagen proportionate area (CPA), to evaluate fibrosis progression and compare it to Ishak stage progression. METHODS: We studied a consecutive cohort of 155 patients with recurrent HCV hepatitis after liver transplantation (LT), who had liver biopsies at one year and were subsequently evaluated for progression of fibrosis using CPA and Ishak staging, and correlated with clinical decompensation. The upper quartile of distribution of fibrosis rates (difference in CPA or Is…
The relationship between transient elastography and histological collagen proportionate area for assessing fibrosis in chronic viral hepatitis
2012
Collagen proportionate area (CPA) has a better correlation with hepatic venous pressure gradient (HVPG) than with Ishak stage. Liver stiffness measurement (LSM) is proposed as non invasive marker of portal hypertension/disease progression. Our aim was to compare LSM and CPA with Ishak staging in chronic viral hepatitis, and HVPG in HCV hepatitis after transplantation. One hundred and sixty-nine consecutive patients with chronic hepatitis B virus (HBV) or hepatitis C virus (HCV) infections pre/post liver transplantation (LT), had a liver biopsy combined with LSM (transient elastography), CPA (biopsies stained with Sirius Red and evaluated by digital image analysis and expressed as CPA) and H…
Computer-assisted image analysis of liver collagen: relationship to Ishak scoring and hepatic venous pressure gradient.
2009
Histopathological scoring of disease stage uses descriptive categories without measuring the amount of fibrosis. Collagen, the major component of fibrous tissue, can be quantified by computer-assisted digital image analysis (DIA) using histological sections. We determined relationships between DIA, Ishak stage, and hepatic venous pressure gradient (HVPG) reflecting severity of fibrosis. One hundred fifteen patients with hepatitis C virus (HCV) who had undergone transplantation had 250 consecutive transjugular liver biopsies combined with HVPG (median length, 22 mm; median total portal tracts, 12), evaluated using the Ishak system and stained with Sirus red for DIA. Liver collagen was expres…
Potential clinical value of quantitative fluorine-18-fluorodeoxyglucose-PET/computed tomography using a graph-based method analysis in evaluation of …
2019
Objectives To identify the clinical relevance of incidentally detected lesions (IDLs) in the gastrointestinal tract (GIT) with 18F-FDG PET/CT and to assess the potential benefit of using semiquantitative PET measures to discern malignant from benign lesions. Methods Forty-one patients who underwent F-FDG PET/CT scans during the oncologic follow-up, revealing abnormal incidental 18F-FDG accumulations in the GIT were included in this retrospective analysis. Incidental PET/CT findings were correlated with endoscopic and histological findings. Semiquantitative PET values (SUVmax, SUVmean, SULpeak, and TLG) were evaluated by using a new graph-based method. Two sample t-test analysis has been per…