Ectopic internal carotid artery presenting as an oropharyngeal mass.

Ectopic internal carotid artery (ICA) is a very rare variation. The major congenital abnormalities of the ICA can be classified as agenesis, aplasia and hypoplasia, and they can be unilateral or bilateral. Anomalies of the neck artery may be vascular neoplasms or ectopic position.

Dosimetric characteristics of a 16-slice computed tomography scanner.

Standard CT dose measurements were performed on a Siemens Sensation 16 scanner. CT dose indices, free-in-air (CTDI(F)) and weighted (CTDI(W)), were measured in all available axial and helical beam collimations of the head and body scanning modes. The effect of tube current, high voltage, rotation time, beam collimation and pitch on the CT doses was investigated.

Fractional anisotropy and mean diffusivity measurements on normal human brain: comparison between low-and high-resolution diffusion tensor imaging sequences.

Non-invasive in vivo visualization of white matter fiber tracts is currently feasible by means of diffusion tensor imaging (DTI) techniques. DTI-derived metrics, like fractional anisotropy (FA) and mean diffusivity (MD), have the potential to improve tissue characterization. Technical optimization of diffusion tensor sequences, including signal-to-noise ratio and spatial resolution, was performed for 20 normal subjects.

Quantification of magnetization transfer rate and native T1 relaxation time of the brain: correlation with magnetization transfer ratio measurements in patients with multiple sclerosis.

The purpose of this paper is to perform quantitative measurements of the magnetization transfer rate (Kfor) and native T1 relaxation time (T1free) in the brain tissue of normal individuals and patients with multiple sclerosis (MS) by means of multiple gradient echo acquisitions, and to correlate these measurements with the magnetization transfer ratio (MTR). Quantitative magnetization transfer imaging was performed in five normal volunteers and 12 patients with relapsing-remitting MS on a 1.5 T magnetic resonance (MR) scanner.

Scleredema adultorum of Buschke presenting as periorbital edema: a diagnostic challenge.

Scleredema adultorum is a rare sclerotic disorder characterized by diffuse swelling and nonpitting induration of the skin. Its occurrence has been documented in association with infections, diabetes mellitus, paraproteinemia, multiple myeloma, and monoclonal gammopathy. We report an unusual case of a 48-year-old man with an asymptomatic bilateral eyelid edema of sudden onset.

Cerebral infections.

Despite the development of many effective antibiotic therapies and the general improvement in hygiene and health care systems all over the world, the incidence of central nervous system (CNS) infection has increased significantly in the past 15 years. This can be attributed primarily to the acquired immunodeficiency syndrome (AIDS) epidemic and its devastating effect on the immune system and secondarily to various immunosuppressive agents that are being used in aggressive cancer treatment and in organ transplantations. The brain particularly is protected from infection by the calvarium, meninges and blood brain barrier.

Stereological estimation of total intracranial volume on CT images.

This study aims to investigate the possibility of generating stereological estimations of total intracranial volume (TIV) on CT scans. The study group included 16 consecutive patients referred for a cranial CT examination. The TIV was estimated using the stereological point counting technique.

T2 relaxation time analysis in patients with multiple sclerosis: correlation with magnetization transfer ratio.

The aim of the current study was to perform T2 relaxation time measurements in multiple sclerosis (MS) patients and correlate them with magnetization transfer ratio (MTR) measurements, in order to investigate in more detail the various histopathological changes that occur in lesions and normal-appearing white matter (NAWM). A total number of 291 measurements of MTR and T2 relaxation times were performed in 13 MS patients and 10 age-matched healthy volunteers. Measurements concerned MS plaques (105), NAWM (80), and "dirty" white matter (DWM; 30), evenly divided between the MS patients, and normal white matter (NWM; 76) in the healthy volunteers.