K Calculation Using Reference Method Corrected Native T for Breast Cancer Diagnosis.

Purpose: The objective of the study is to use multiple tube phantoms to generate correction factor at different spatial locations for each breast coil cuff to correct the native T value in the corresponding spatial location of the breast lesion. The corrected T value was used to compute K and analyze its diagnostic accuracy in the classification of target condition, i.e.

Use of Multiple-Tube Phantom: A Method to Globally Correct Native T1 Relaxation Time Inhomogeneity in Dedicated Molecular Magnetic Resonance Breast Coil.

Background: Native T1 relaxation time (T1) presents an important prerequisite to reliably quantify pharmacokinetic parameter like K (volume transfer constant). Native T1 value can be varied because of the inhomogeneity in the breast coil, thus influencing the K measurement.

Purpose: The current study aims to design and use a phantom with multiple tubes for both breast cuffs to assess native T1 inhomogeneity across the dedicated molecular magnetic resonance (mMR) breast coil and adopt corrective method to spatially normalize T1 values to improve homogeneity.

Association of pharmacokinetic and metabolic parameters derived using simultaneous PET/MRI: Initial findings and impact on response evaluation in breast cancer.

Purpose: To study relationships among pharmacokinetic and F-fluorodeoxyglucose (F-FDG) PET parameters obtained through simultaneous PET/MRI in breast cancer patients and evaluate their combined potential for response evaluation.

Methods: The study included 41 breast cancer patients for correlation study and 9 patients (pre and post therapy) for response evaluation. All patients underwent simultaneous PET/MRI with dedicated breast imaging.

Numerical modeling of vessel geometry to measure hemodynamics parameters non-invasively in cerebral arteriovenous malformation.

Cerebral arteriovenous malformations (CAVM) are congenital lesions that contain a cluster of multiple arteriovenous shunts (NIDUS). Cardiac arrhythmia in CAVM patients causes irregular changes in blood flow and pressure in the NIDUS area. This paper proposes the framework for creating the lumped model of tortuous vessel structure near NIDUS based on radiological images.

Computer simulation of Cerebral Arteriovenous Malformation-validation analysis of hemodynamics parameters.

Problem: The purpose of this work is to provide some validation methods for evaluating the hemodynamic assessment of Cerebral Arteriovenous Malformation (CAVM). This article emphasizes the importance of validating noninvasive measurements for CAVM patients, which are designed using lumped models for complex vessel structure.

Methods: The validation of the hemodynamics assessment is based on invasive clinical measurements and cross-validation techniques with the Philips proprietary validated software's Qflow and 2D Perfursion.

Role of pharmacokinetic parameters derived with high temporal resolution DCE MRI using simultaneous PET/MRI system in breast cancer: A feasibility study.

Purpose: To evaluate the reliability of pharmacokinetic parameters like K, Kep and v derived through DCE MRI breast protocol using 3T Simultaneous PET/MRI (3Tesla Positron Emission Tomography/Magnetic Resonance Imaging) system in distinguishing benign and malignant lesions.

Materials And Methods: High temporal resolution DCE (Dynamic Contrast Enhancement) MRI performed as routine breast MRI for diagnosis or as a part of PET/MRI for cancer staging using a 3T simultaneous PET/MRI system in 98 women having 109 breast lesions were analyzed for calculation of pharmacokinetic parameters (K, v, and Kep) at 60s time point using an in-house developed computation scheme.

Results: Receiver operating characteristic (ROC) curve analysis revealed a cut off value for K, Kep, v as 0.

Role of quantitative pharmacokinetic parameter (transfer constant: K(trans)) in the characterization of breast lesions on MRI.

Background: The semi-quantitative analysis of the time-intensity curves in dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) has a limited specificity due to overlapping enhancement patterns after gadolinium administration. With the advances in technology and faster sequences, imaging of the entire breast can be done in a few seconds, which allows measuring the transit of contrast (transfer constant: K(trans)) through the vascular bed at capillary level that reflects quantitative measure of porosity/permeability of tumor vessels.

Aim: Our study aims to evaluate the pharmacokinetic parameter K(trans) for enhancing breast lesions and correlate it with histopathology, and assess accuracy, sensitivity, and specificity of this parameter in discriminating benign and malignant breast lesions.

Optimizing MRI scan time in the computation of pharmacokinetic parameters (K(trans) ) in breast cancer diagnosis.

Purpose: To assess the effects of reduced scan time in dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) of breast for the evaluation of pharmacokinetic parameters (K(trans) , ve , and kep ).

Materials And Methods: High temporal resolution DCE-MRI was performed for calculation of pharmacokinetic parameters (K(trans) , ve , and kep ) at different timepoints using an in-house developed computation scheme adopting the standard model (SM).

Results: The receiver operating characteristic (ROC) curve analysis revealed an area under the ROC curve (AUC) of 0.

Handcrafted fuzzy rules for tissue classification.

This article proposes a handcrafted fuzzy rule-based system for segmentation and identification of different tissue types in magnetic resonance (MR) brain images. The proposed fuzzy system uses a combination of histogram and spatial neighborhood-based features. The intensity variation from one type of tissue to another is gradual at the boundaries due to the inherent nature of the MR signal (MR physics).

A soft-segmentation visualization scheme for magnetic resonance images.

Prevalent visualization tools exploit gray value distribution in images through modified histogram equalization and matching technique, referred to as the window width/window level-based method, to improve visibility and enhance diagnostic value. The window width/window level tool is extensively used in magnetic resonance (MR) images to highlight tissue boundaries during image interpretation. However, the identification of different regions and distinct boundaries between them based on gray-level distribution and displayed intensity levels is extremely difficult because of the large dynamic range of tissue intensities inherent in MR images.