Automated breast image classification using features from its discrete cosine transform.

Purpose: This work aimed to improve breast screening program accuracy using automated classification. The goal was to determine if whole image features represented in the discrete cosine transform would provide a basis for classification. Priority was placed on avoiding false negative findings.

Automatic detection of anomalies in screening mammograms.

Background: Diagnostic performance in breast screening programs may be influenced by the prior probability of disease. Since breast cancer incidence is roughly half a percent in the general population there is a large probability that the screening exam will be normal. That factor may contribute to false negatives.

Neuroimaging assessment of memory-related brain structures in a rat model of acute space-like radiation.

Purpose: To investigate the acute effects on the central nervous system (CNS) of (56)Fe radiation, a component of high-energy charged particles (HZE) in space radiation, using quantitative magnetic resonance imaging (MRI) noninvasively.

Materials And Methods: Sprague-Dawley rats were exposed to whole-brain (56)Fe (0, 1, 2, and 4 Gy). At 1 week postirradiation, MRI scans were made using T2-weighted (T2WI), diffusion-weighted (DWI), and contrast enhanced T1-(CET1) imaging.

Nuclear magnetic resonance spectroscopy of bovine ovarian follicular fluid at four selected times of the oestrous cycle.

The objective of the study was to determine if nuclear magnetic resonance (NMR) spectral features of ovarian follicular fluid were correlated with the physiological status of follicles so that we could assess the feasibility of using NMR spectroscopy during assisted reproduction therapy. Thirty-five sexually mature, nullparious heifers were monitored by transrectal ultrasonography to assess their follicle wave status during the oestrous cycle. Ovariectomies were performed on Day 3 of wave 1 (D3W1, n = 10), Day 6 of wave 1 (D6W1, n = 9), Day 1 of wave 2 (D1W2, n = 9), or in the immediate preovulatory period of at least 17 days after ovulation (De17, n = 9).

Automated search for arthritic patterns in infrared spectra of synovial fluid using adaptive wavelets and fuzzy C-means analysis.

Analysis of synovial fluid by infrared (IR) clinical chemistry requires expert interpretation and is susceptible to subjective error. The application of automated pattern recognition (APR) may enhance the utility of IR analysis. Here, we describe an APR method based on the fuzzy C-means cluster adaptive wavelet (FCMC-AW) algorithm, which consists of two parts: one is a FCMC using the features from an M-band feature extractor adopting the adaptive wavelet algorithm and the second is a Bayesian classifier using the membership matrix generated by the FCMC.

Neuroprotection from soman-induced seizures in the rodent: evaluation with diffusion- and T2-weighted magnetic resonance imaging.

Exposure to the organophosphate nerve agent soman produces seizures that in turn lead to neuropathology. This study describes the temporal and spatial evolution of brain pathology following soman-induced convulsions and the attenuation of these alterations after neuroprotective intervention with magnetic resonance imaging (MRI). Neuroimaging 12 h after soman exposure, the hippocampus and thalamus exhibited significant decreases (23%) in apparent diffusion coefficients (ADC).

Reconsideration of pacemakers and MR imaging.

The presence of an implanted pacemaker is widely regarded as an absolute contraindication to magnetic resonance (MR) imaging; however, this viewpoint is based largely on safety concerns in the 1982-1996 period. Since 1996, changes in pacemaker electronics including decreased ferromagnetic content, increased sophistication of the circuitry, and onboard computer capabilities suggest that the absolute contraindication of MR imaging for pacemaker patients should be reconsidered. In addition, there are now data from prospective trials of 232 patients with demand pacemakers who underwent MR imaging at 0.

Neuronal and glial cell populations in the piriform cortex distinguished by using an approximation of q-space imaging after status epilepticus.

Background And Purpose: Temporal lobe epilepsy produces an injury cascade that includes neuronal loss and gliosis. The pilocarpine model reliably reproduces the symptoms of temporal lobe epilepsy and the resulting neuronal glial changes can be accurately depicted on diffusion-weighted images. The judicious choice of diffusion-encoding gradients can isolate multiple apparently isochromatic diffusing populations, but the assignment of these populations to specific tissue characteristics has been difficult.

Magnetic resonance diffusion imaging of ovarian masses: a first experience with 12 cases.

Objective: The objective of the study was to determine the feasibility of using apparent diffusion coefficient (ADC) measurement for the differential diagnosis of malignancy in ovarian masses.

Materials And Methods: Twelve cases involving ovarian masses were imaged using spin echo diffusion magnetic resonance imaging (MRI). Five cases involved malignant ovarian masses, on the basis of postoperative histologic examination, and the rest involved benign masses.

Recurrent nonstatus generalized seizures alter the developing chicken brain.

Purpose: Noninvasive magnetic resonance imaging was used to assess the evolution of seizure-induced pathology in epileptic, carrier, and normal chickens. Our objective was to determine whether repetitively evoked seizures in an epileptic fowl model of generalized seizures resulted in altered brain development.

Methods: Data were obtained from seizure and control groups at 45, 90, and 180 days after hatching.

Water self-diffusion tensor changes in an avian genetic developmental model of epilepsy.

Diffusion tensor imaging (DTI) was used to investigate whether tissue anisotropy in the developing brain is modified by recurrent seizures in epileptic chickens. Twelve epileptic chickens were sorted equally into two experimental groups at 10 days old. Until the age of 180 days, one group was photically stimulated beginning at an age of 2 weeks and repeated every 2 days while the other group was not stimulated.

Evolution of beta-amyloid induced neuropathology: magnetic resonance imaging and anatomical comparisons in the rodent hippocampus.

Alzheimer's disease (AD) is characterized by the anatomical appearance of beta-amyloid (betaA) plaques and neurofibrillary tangles. These changes are also associated with cyclical inflammation, oxidative damage and, as inferred from the autopsied brains of patients, progressive injury to neurons. Here, we report the short-term effects of an intrahippocampal injection of the toxic betaA peptide fragment 25-35 in rats using quantitative magnetic resonance imaging (MRI) methods.