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The prevalence of atherosclerosis at the carotid bifurcation and in the siphon was reviewed in 141 patients who underwent 149 endarterectomies. The relationship between the presence and severity of siphon lesions and focal neurologic symptoms, both before and after operation, was also examined. Siphon disease was found in 84% of the 282 sides. Most lesions (42%) were in the 20% to 49% diameter-reduction category. Only 9% were stenoses greater than 50%, and 10% were occlusions. The majority (65%) were smooth. No relationship was found between the severity of disease at the carotid bifurcation and in the siphon. No pattern of siphon disease could be related to the occurrence of symptoms. Furthermore, no relation was found between the severity of siphon disease and recurrent symptoms after endarterectomy.

Forty-six consecutive studies of carotid bifurcations were done with a Hokanson Ultrasonic Arteriograph before contrast arteriography. Based on the Doppler signal and the oscilloscopic image, each internal carotid artery was sorted into one of four categories as an estimation of the percent diameter reduction: less than or equal to 10 percent, 10 percent to 49 percent, 50 percent to 99 percent, and total occlusion. These results were compared with the percent diameter reduction determined from contrast arteriograms by a vascular radiologist unaware of the noninvasive test results. Overall, 83 percent of the arteries were correctly categorized. Detection of stenosis in the 50 percent to 99 percent range was 89 percent accurate. The sensitivity and specificity in detecting a 50 percent or greater stenosis were both 96 percent.

Duplex scanning provides real time B-mode images of the carotid bifurcation vessels along with a single gate pulsed Doppler flow velocity detector. By using the B-mode output of the duplex system to measure the Doppler angle and spectrum analysis to measure the frequency content of the Doppler signal, instantaneous flow velocity can be calculated. Mean velocity at peak systole was calculated retrospectively in 68 common (CCA) and internal (ICA) carotid arteries of 39 patients who had undergone prior angiography and prospectively in 30 arteries of 15 healthy young controls. The ratio of mean peak ICA velocity to mean peak CCA velocity at systole (VICA/VCCA) was below 0.8 in all 36 normal arteries and above 1.5 in all 21 high-grade stenoses of 60% or greater diameter reduction. Sixty-one percent of 41 vessels with less than 10 to 55% diameter reduction had a velocity ratio between 0.8 and 1.5. Only 10% of all ICA's with any stenotic lesion were incorrectly classified as normal. VICA/VCCA appears to be an accurate indicator of the degree of ICA stenosis.

With oculoplethysmography, conclusions are drawn regarding the state of internal carotid artery disease by measurements based upon pressure and flow in the eye, a location far removed from the site of the disease. Thus, many potential variables including ocular disease, vessel wall properties, intracranial atherosclerosis and collateral flow may affect the results. Although oculoplethysmography was quite accurate in detecting occlusion of the internal carotid artery, the identification of a high grade stenosis was much less precise. Furthermore, it could not distinguish between stenosis and occlusion, making angiography necessary for accurate diagnosis. In this study, oculoplethysmography, either alone or in combination with carotid phonoangiography, was not of sufficient accuracy to recommend its use as part of a noninvasive evaluation of carotid artery occlusive disease.

The duplex ultrasonic scanner combines real-time B-mode imaging with a single-gate, variable-range pulsed Doppler. The detection and categorization of the severity of carotid artery atherosclerosis is achieved by performing spectral analysis of the pulsed Doppler velocity signal obtained from vessels of interest. Using this technique, 750 patients with suspected extracranial carotid artery disease were evaluated between January 1978 and January 1980. One hundred thirty-five of these 750 patients (18%) underwent cerebral arteriography performed with biplanar views of the carotid bifurcation. The degree of stenosis was measured independently in these patients and was available for comparison with the results of duplex scanning and spectral analysis. Duplex scanning correctly detected the presence of disease in 252 of 259 carotid arteries studied (97%). The extent of involvement varied from plaques that produced less than 10% diameter reduction to those that resulted in a total occlusion. The technique was less accurate with lesions that produced less than 10% diameter reduction.

The authors report a case of regional enteritis complicated by nephrocalcinosis and nephrolithiasis. Enteric hyperoxaluria is documented and the pathophysiology is discussed.

We assessed the prognostic value of cardiothoracic ratio and plain film heart volume in relation to other clinical, exercise, hemodynamic and quantitative angiographic variables. Both cardiothoracic ratio and plain film heart volume are highly sensitive, but nonspecific, indicators of abnormal left ventricular end-diastolic volume and ejection fraction. Both variables are univariately important predictors of survival in cohorts of medically and surgically treated heart disease patients. Plain film heart volume significantly adds to the multivariate prediction of prognosis obtained from groups of clinical, exercise, hemodynamic and quantitative angiographic variables. These measurements from the routine chest roentgenogram are sensitive detectors of abnormal left ventricular function or volume and important predictors of long-term survival. The fact that they contribute prognostic information in addition to left ventricular volume and ejection fraction suggests that other cardiac chamber volumes are of prognostic importance.

The arteriograms of 109 patients with symptomatic cerebral ischemia were analyzed to determine the distribution of extracranial and intracranial vascular abnormalities. In the 66 patients with transient hemispheric or ocular ischemia, potentially embolic lesions were more common than hemodynamically significant lesions (84% versus 50%). In the 29 patients with fixed neurologic deficits, 25% had occlusion of the internal carotid artery on the appropriate side; ulcerated lesions were again more common in the remaining patent arteries than were hemodynamically significant lesions. The major difference between the transient group and the fixed group was the 29% incidence of intracerebral disease or anomaly in the transient group, with similar lesions in 90% of the group with fixed neurologic deficit. Symptoms of cerebral ischemia are more likely to be related to ulceration than to hemodynamically significant lesions. The risk of stroke seems greatest when there is also intracerebral siphon disease or anatomic anomaly of the circle of Willis.

A minicomputer based pattern recognition method has been used to prospectively classify the category of disease involvement of 105 carotid arteries. The system utilized spectral patterns obtained from a combined B-mode/pulsed Doppler unit. All decisions are based upon comparison of an unknown, averaged waveform with a series of vessels with known severity of disease. The variability in the computer decision as compared to arteriography is discussed.

One hundred twenty eight cervical carotid arteriograms were twice viewed by three readers for the evaluation of atherosclerotic disease at the carotid bifurcation. Stenoses were estimated using calipers to the nearest 5% and lesions were qualitatively characterized as smooth, irregular, or ulcerated. The intraobserver correlation coefficient between estimates of percent stenosis was .94 overall and .98 for the internal carotid artery. The average intraobserver variability in estimating percent stenosis was 5.23% for all vessels and 6.04% with a standard deviation of 8.09% for the internal carotid artery. The intraobserver percent agreement at a fixed stenosis is defined as the percent of the time one reader on two readings would read at least the fixed percent stenosis among cases that might be read as having the fixed percent stenosis. The intraobserver percent agreement rate for the internal carotid artery was 95.9% at greater than 0% stenosis, 90.4% for 50% or greater stenosis, and 96.8% for 100% stenosis (total occlusion). The interobserver correlation coefficient between readers was .92 overall and .97 for the internal carotid artery. The absolute difference in percent stenosis between readers was 7.21% for all vessels and 8.64% for the internal carotid artery with a standard deviation of 9.5%. The interobserver agreement rate for the internal carotid artery at greater than 0% stenosis was 93.0%, 85.4% for 50% or greater stenosis and 96.8% at 100% stenosis. The addition of oblique views had no statistical effect on estimates of percent stenosis but increased the frequency with which irregularity and ulceration were diagnosed in the internal carotid artery.

Moyamoya is an intriguing and controversial syndrome. This patient study serves to align the pathophysiology of intracranial hemorrhage in moyamoya with the cerebral vascular disease seen with hypertension, or aging. The historical evidence linking lipohyalinosis and microaneurysms to cerebral hemorrhage is reviewed, the pathogenesis of this angiopathy is discussed, and explanations considered for its association with the vascular pattern of moyamoya. We propose that hemodynamics, genetics or both are among the primary operant etiologic factors.

The nature of pleural based radiographic opacities in the chest can be uncertain; however, ultrasonic examination provides a reliable means of distinguishing solid from fluid-containing lesions. It is superior to both fluoroscopy and radiography in accurately localizing loculated fluid collections for thoracentesis and can be performed with commercially available gray scale contact scanning equipment. Cases representing a spectrum of clinical applications are discussed.

Ten radiologists at three levels of training visually assessed total heart and individual chamber size in 95 adults of both sexes with well defined cardiac diagnoses. Overall accuracy was highest for total heart size (82.2% correct), followed by left ventricular size, left atrial size and right heart size 79.6%, 75.0%, and 72.8%, respectively. Right heart and left atrial enlargement had a statistically significant negative effect on visual assessment of other chambers (P less than .05). Attempts to subclassify left ventricular enlargement into hypertrophy and hypertrophy and dilatation groups proved unsuccessful. While 63% of the hypertrophy group was detected as abnormal, only 24.3% were correctly subclassified as hypertrophy. For the hypertrophy and dilatation group, the corresponding values were 82% and 70%, respectively. Oblique views were useful in assessing left ventricular size only when inexperienced observers were included in the group of evaluators (P less than .05). A statistically significant improvement in assessment of normal left ventricular size and overall left atrial size was noted with experience (P less than .01 and P less than .05, respectively).

The results of ultrasonic duplex scanning combined with spectral analysis are compared with the results of contrast angiography in patients after endarterectomy in which recurrence of carotid arterial disease was suspected. Thirty-six patients underwent a duplex scan study within 3 months of their post-operative angiogram, performed at their physician's discretion (44 studies). The overall accuracy of the method was 80%. Our ability to predict a greater than 50% diameter reduction along with total occlusion was 94%. The measure of agreement corrected for chance between arteriography and duplex scanning as expressed by the Kappa statistic was 0.675 +/- SE (K) 0.096. This level of agreement compared favorably to that of inter- and intra-observer variability in reading cerebral angiograms. The accuracy reported justifies the clinical use of ultrasonic duplex scanning in the detection of recurrent stenosis after carotid endarterectomy.

Ultrasonic imaging of the cervical carotid arteries by ultrasonic arteriography and duplex scanning combined with pulsed Doppler spectrum analysis were investigated in a series of patients undergoing arteriography. By using the ultrasonic image as a guide for precise placement of the pulsed Doppler sample volume, the characteristics of blood flow at points of interest in the carotid arteries could be determined. Audible analysis of the Doppler signal permitted correct diagnosis of 23 of 26 (88%) high-grade stenoses or occlusions with ultrasonic arteriography and 24 of 26 (92%) with duplex scanning. Spectrum analysis of Doppler signals obtained with the duplex scanner detected all of the 22 high-grade stenoses. Spectral abnormalities of a lesser degree also were detected in 18 of 23 vessels (78%) with atherosclerotic plaques which should not have reduced cerebral blood flow. These techniques permit the accurate detection of and the distinction between high-grade stenoses and occlusion, as well as the identification of many plaques which are not large enough to affect intracranial hemodynamics.

A geometric representation of the carotid bifurcation is presented with data obtained from biplane angiograms of normal branches and branches exhibiting less than 5% vessel diameter reduction. Three features are identified that are of importance in the interpretation of ultrasonic Doppler velocity information and in the design of engineering flow models for evaluation of carotid branch hemodynamics: the variability of the bifurcation angles, the degree of tortuosity, and the nonplanar nature of the branches. In addition, data collected demonstrate the potential usefulness of the common carotid artery as a reference diameter in evaluating stenosis of the carotid bulb.

A papillary adenoma of the gall bladder was demonstrated by gray scale echography. The pathology of the tumor was described and the ultrasonic characteristics which distinguish it from a calculus were discussed.

A myelolipoma of the adrenal gland is reported. Diagnostic features include (1) hyperlucent mass on intravenous pyelography with renal displacement, (2) an avascular mass on arteriography and venography, (3) solid tissue mass on B-mode ultrasonography, and (4) no clinical or chemical evidence of adrenal hyperfunction.

In 76 adult males quantitative angiographic measurements of left ventricular size were compared to 12 plain chest film measurements of heart size and shape. Of the 18 normal cases, only Rigler's B measurement correlated with left ventricular volume (r = .64). However, this correlation was not statistically significant. Of the 58 patients with isolated aortic valve disease, 19 had increased left ventricular mass (hypertrophy) and 39 had both increased left ventricular end-diastolic volume and mass (hypertrophy and dilatation). In the hypertrophy group, plain film heart volume was the most sensitive detector of an enlarged left ventricle (21% false negative rate) and correlated with left ventricular end-diastolic volume (r = .62). Using stepwise discriminant analysis, the combination of heart volume, leftness of the heart, apex position, and roundness of the left ventricle decreased the false negative rate to 5%. In the hypertrophy and dilatation group, plain film heart volume had the highest correlation with left ventricular volume and mass (r = .66) and a false negative rate of 8%. No single variable or combination of variables could usefully discriminate between the hypertrophy and hypertrophy and dilatation groups. These data support the conclusion that plain film heart volume is the best single measurement for detecting left ventricular enlargement.

The results of ultrasonic pulsed Doppler duplex scanning with spectral analysis and computer pattern recognition are compared with the results of contrast arteriography in patients screened for extracranial carotid artery disease. The intraangiographer variability (one radiologist reading the same films twice) and the interangiographer variability (two radiologists reading the same film independently) were also studied. To calculate degrees of agreement corrected for chance, the Kappa statistic was computed for all the evaluation methods employed. At the present time, the concordance between spectral analysis and cerebral contrast angiography reaches a Kappa value of 0.682 +/- 0.064. This level of agreement compares favorably with the interangiographer agreement level (K = 0.568 +/- 0.058) and the intraangiographer agreement (K = 0.711 +/- 0.054). The computer pattern recognition program predicted the degree of stenosis by angiography with an agreement of K = 0.721 +/- 0.059. This concordance compares favorably to that observed when the radiologists are compared with themselves and is greater than that reached by two different radiologists. The continuous improvement in precision and accuracy of duplex scanning offers the promise of its usefulness in clinical and epidemiological studies.