Registration of three-dimensional MR and CT studies of the cervical spine

A three-dimensional image registration technique for CT and MR studies of the cervical spine was evaluated for feasibility and efficacy. Registration by means of external fiducial markers was slightly more accurate than registration by anatomic landmarks. The interrelationships between bony (eg, neural foramina) and soft tissue structures (eg, nerve roots) in the cervical spine were more conspicuous on registered images than on conventional displays. Registration of CT and MR images may be used to examine more precisely the relationships between bony and soft tissue structures of the cervical spine.

Transcranial color Doppler sonography of basal cerebral arteries in 182 healthy subjects: age and sex variability and normal reference values for blood flow parameters

OBJECTIVE

Only a limited number of transcranial color-coded Doppler studies have provided ranges for the normal reference values of cerebral hemodynamic parameters. These reports are not fully convergent in relation to the range of values or to the age and sex dependence of blood flow parameters. The aim of the present study was to provide data regarding normal reference ranges.

SUBJECTS AND METHODS

We examined 182 healthy volunteers (79 men and 103 women; age range, 20-86 years old) with color-coded Doppler sonography via a temporal acoustic window with a 2.5-MHz transcranial probe. The subjects were divided into three age groups: 20-40 years old (group 1), 41-60 years old (group 2), and more than 60 years old (group 3). Angle-corrected peak systolic, end-diastolic, and mean velocities as well as impedance indexes were determined in anterior, middle, and posterior cerebral arteries.

RESULTS

Mean velocity values for middle, anterior, and posterior cerebral arteries in age group 1 were 81+/-20, 56+/-14, and 52+/-12 cm/sec (mean +/- SD), respectively. In group 2, the values were 73+/-19, 53+/-16, and 51+/-12 cm/sec (mean +/- SD), and in group 3, the values were 59+/-11, 44+/-11, and 40+/-9 cm/sec (mean +/- SD). Decrease in blood flow velocities and a concomitant increase in impedance indexes were found in all vessels with advancing age-findings that were most pronounced in subjects who were more than 40 years old. In the 20- to 40-year-old group, mean velocities for all vessels were higher in women than in men, whereas impedance indexes were not significantly different.

CONCLUSION

Flow velocities in basal cerebral arteries range widely and are significantly age dependent. Age and sex matching of Doppler sonographic data is a prerequisite for clinically valuable conclusions.

Ultrasound vascular imaging with subtraction in evaluation of lung tumor vascularity--a case report

Ultrasound vascular imaging with subtraction is considered as very useful method to evaluation vascularity of tumor and its relationships to great vessels. Lung tumor was evaluated with power color Doppler ultrasound with and without B-mode scanning. Power color Doppler imaging without B-mode scanning is better depicted tumor internal vascular architecture and its relationships to great vessels then with B-mode. This method makes differentiation of tumor character possibly and interventional procedures more safely.

Evaluation of colour Doppler sonography in lung tumor biopsy

Between 1986 and 1995, 1800 ultrasound examinations of the chest were done. Addition of colour Doppler imaging improves safety of procedures and allowed to perform ultrasound guided biopsy in 47 patients. On the basis of our experience we state that colour Doppler sonography guided needle aspiration biopsy is useful, sufficient and safety diagnostic method of malignant lung masses, especially peripheral and wall-chest located.

Focal solitary hypoechoic area in hepatic fatty infiltration: a cause of hepatic pseudomass in ultrasound examination

A unusual pattern of hepatic fatty infiltration was detected sonographically in 43 patients over a 2-year period. At appropriate gain settings and time gain compensations, the liver parenchyma demonstrated diffuse increased echogenicity except for a solitary hypoechoic area with relatively distinct margins, usually locate in the medial segment of the left hepatic lobe or right lobe in pericholecystic, perivascular or subcapsular locations. This hypoechoic focus varied in size between 15 and 50 mm and was typically ovoid, but was occasionally spherical or irregular in shape. Fourteen patients with such skip area underwent percutaneous needle biopsy because of concern that there was a space-occupying mass. Microscopic examination of specimens from the hypoechoic region revealed normal hepatic parenchymal cells, while tissue samples from the surrounding liver had high fat levels. In the remaining 29 patients, correlative radiologic studies supported the diagnosis of fatty liver and excluded a central-mass lesion. A localized area of normal hepatic tissue should be considered among the possible hypoechoic periportal area demonstrated within a fatty liver.