PubMed HealthSearch

Biomedical subjects

W D Foley

Publications and source records attributed to W D Foley.

At least 19 recordsLinked to original sources

Color Doppler ultrasonography in the evaluation of the acute scrotum.

Color Doppler ultrasonography was used to assess 20 patients with the acute onset of scrotal pain. Patients were categorized into 3 groups according to the initial clinical impression of the examining physician: ischemia, inflammation or trauma. Color Doppler ultrasonography correctly predicted the need for surgery in 8 of 9 operated patients (89%) and correctly predicted the outcome in all 11 nonoperated patients (100%). The anatomical resolution possible, as well as information regarding blood flow made color Doppler ultrasonography a useful tool in the assessment of acute scrotal processes.

Acute Disease

Color Doppler sonography in the evaluation of erectile dysfunction.

Color Doppler sonography can be useful in the evaluation of erectile dysfunction, which can result from psychogenic, endocrinologic, neurogenic, pharmacologic, and vasogenic causes. It is used to determine the integrity of the vascular mechanism. After an intracavernosal injection of a vasodilatory agent, color Doppler sonography is performed to evaluate cavernosal arteries and dorsal vessels. Color flow imaging allows direct visualization of intrapenile anatomy, vascular variants, and disease. It is also helpful in demonstrating transitions in cavernosal and dorsal blood flow. Color Doppler sonography is combined with spectral interrogation of the cavernosal arteries and dorsal veins to help determine peak systolic and end-diastolic velocities. Cavernosal artery size and systolic velocities help diagnose arterial insufficiency. Recent work on cavernosal artery diastolic flow and dorsal vein flow has indicated that color Doppler sonography, when correlated with cavernosographic findings, may be helpful in diagnosing venous incompetence. Temporal variations in transitions in cavernosal artery and dorsal vein flow during various stages of erection are important in the accurate diagnosis of vasogenic impotence.

Color

Evaluation of traumatic aortic injury: does dynamic contrast-enhanced CT play a role?

To investigate the value of 5-mm contrast material-enhanced computed tomography (CT) in patients with moderate to low probability of aortic laceration after a substantial deceleration injury, scans were obtained through the upper mediastinum in 160 consecutive patients. Thoracic angiography and aortography were performed in patients with evidence of mediastinal hemorrhage at CT. There was no evidence of mediastinal hemorrhage in 132 patients with normal admission chest radiographs. In the 28 patients with abnormal admission chest radiographs, CT helped exclude mediastinal hemorrhage in 22 patients (78%), and 19 patients (68%) were treated without undergoing angiography. Six patients had mediastinal hematoma at CT. Only one had an aortic laceration at angiography. The authors conclude that 5-mm contrast-enhanced CT can help exclude mediastinal hemorrhage and reduce the angiography rate in low-to-moderate-risk patients with a widened or indeterminate mediastinum. There were no unsuspected cases of mediastinal hemorrhage in patients with normal chest radiographs. Angiography is recommended for patients considered to be at high risk for aortic laceration.

Angiography

Ureteric jets: evaluation of normal flow dynamics with color Doppler sonography.

This study was designed to investigate a variety of sonographic features of ureteric jets in order to define patterns of flow and ranges of flow values in an asymptomatic population. The following features of ureteric jets were measured during a period of up to 30 min in a group of 15 asymptomatic volunteers after oral hydration (the mean value was calculated on each side): peak velocity (mean, 57 cm/sec); jet duration (mean, 4.6 sec); and number of peaks and subpeaks (mean, 2.2). Several flow patterns were observed, including discrete jets, ureteric streaming, and rest periods. For each patient the ratios of values obtained on the left and right sides were calculated for peak velocity (1.00-1.74; mean, 1.26); jet duration (1.00-4.69; mean, 1.83); and jet frequency (1.00-1.21; mean, 1.11). The interjet interval (period between jets) ranged from 2 to 150 sec. Bolus volume and jet frequency showed simultaneous moment-to-moment variation. The frequency and velocity rather than the duration ratios may be of greatest value in identifying patients with normal ureterodynamics. Our findings challenge two current concepts of renal pelvic and ureteral response to changes in urine output: (1) ureters have a fixed maximal discharge rate and (2) bolus volumes do not change until this rate is achieved. Asymmetric moment-to-moment fluctuations observed in jet frequency suggest that prolonged examination may be necessary to confirm normal symmetry of jet frequency in some patients with suspected ureteric obstruction.

Adult

Color Doppler sonography in the evaluation of the adult acute scrotum.

Color Doppler sonography (CDS) was used to evaluate 35 adult males with acute scrotal discomfort. Correlative nuclear scintigraphy was performed in 15 patients. Surgical correlation was available in 10 patients with clinical follow-up in the remaining 25. The complete absence of intratesticular color flow was used as our criterion for testicular ischemia. This was found to be 100% sensitive and 100% specific in 8 patients with surgically confirmed testicular ischemia. Spontaneous detorsion was noted in one patient with hyperemia demonstrated by color imaging. Increased color flow was found in 20 patients with the clinical impression of scrotal inflammation. Nuclear scintigraphy and color Doppler imaging had 100% agreement in 15 patients. Color Doppler sonography is a useful and highly accurate diagnostic method in the evaluation of patients with the acute scrotal syndrome. Color flow imaging is comparable to nuclear scintigraphy in the diagnosis of testicular ischemia.

Acute Disease

Hepatic metastases: CT versus MR imaging at 1.5T.

A prospective multi-institutional study was performed to compare the sensitivity of computed tomography (CT) and high-field magnetic resonance (MR) imaging (1.5T) in the detection of hepatic metastases. T1-weighted and 72-weighted spin-echo (SE) MR images were compared with noncontrast, dynamic, and delayed CT. Sixty-nine oncology patients were studied. Noncontrast CT showed an overall sensitivity of 57%, dynamic CT 71%, delayed CT 72%, T1-weighted SE MR 47%, and T2-weighted SE MR 78%. Although there was no statistically significant (p less than 0.05) difference among dynamic CT, delayed CT, and T2-weighted SE MR, these three methods were significantly more sensitive (p less than 0.005) than noncontrast CT or T1-weighted SE MR. T2-weighted SE MR was significantly more sensitive (p less than 0.006) than CT or T1-weighted SE MR in the detection of small (less than 1 cm) lesions. CT was more sensitive in the detection of extrahepatic disease. These data confirm the superiority of T2-weighted SE over T1-weighted SE pulse sequences at 1.5T.

Adult

Color Doppler flow imaging.

The performance requirements and operational parameters of a color Doppler system are outlined. The ability of an operator to recognize normal and abnormal variations in physiologic flow and artifacts caused by noise and aliasing is emphasized. The use of color Doppler flow imaging is described for the vessels of the neck and extremities, upper abdomen and abdominal transplants, obstetrics and gynecology, dialysis fistulas, and testicular and penile flow imaging.

Abdomen

Color Doppler sonography in the evaluation of erectile dysfunction: patterns of temporal response to papaverine.

Most studies of duplex Doppler sonography for the assessment of erectile dysfunction involve determination of peak systolic velocities 5 min after intracavernosal injection of papaverine. The purpose of this study was to determine the effect of the timing of Doppler measurements of flow after papaverine injection for establishing the presence of arterial and venous abnormalities. Color Doppler sonography was performed in 75 patients for evaluation of vasculogenic impotence. After intracavernosal injection of 60 mg of papaverine, measurements of peak systolic and end-diastolic velocities were obtained in each cavernosal artery at 5-min intervals for a total of 30 min. A peak systolic velocity of less than 25 cm/sec was used as the threshold for arterial insufficiency. An end-diastolic velocity of greater than 5 cm/sec was used to predict venous incompetence. Scanning was performed for direct assessment of dorsal venous flow. Thirty patients were subsequently evaluated by cavernosometry and cavernosography. In most patients (76%), maximum response to papaverine was achieved within the first 5 min. In eight patients, significant increases in systolic velocity were seen only after 5 min. In 10 patients, significant changes in end-diastolic velocity between 5 and 30 min resulted in diagnostic reclassification. Data acquisition for 30 min significantly improved the sensitivity (95%) and specificity (83%) for the prediction of venous incompetence in patients with correlative cavernosography. Transient, early dorsal vein flow was noted in normal subjects. Persistent dorsal vein flow had an 80% sensitivity and 100% specificity for venous incompetence. Our results suggest that, when using color Doppler sonography, gathering data for 30 min may improve the prediction of vasculogenic impotence.

Adult

Evaluation of renal transplant dysfunction using color Doppler sonography.

Color Doppler sonography (CDS) detects changes in renal blood flow that may be useful in evaluating renal transplant dysfunction (RTD). To assess the performance of CDS as a clinical test, we reviewed results from 223 CDS measurements in 130 renal transplant recipients during a 26 month period. Spectral wave forms were characterized by pulsatility index (PI) (maximum frequency shift minus minimum frequency shift divided by mean frequency shift). In 27 individuals with stable renal function, mean PI was 1.80 +/- 0.23 (S.D.). Abnormal PI were subsequently defined as greater than two S.D. more than the mean (PI greater than or equal to 2.3). CDS performed during the early post-transplant period (n = 91) could not differentiate acute tubular necrosis (ATN), obstruction and rejection. Abnormal studies were seen in 35 of 46 instances of ATN and in three of obstruction. In 132 studies done after the postoperative period, CDS became abnormal during rejection episodes in only 45 of 71 instances (sensitivity rate of 63 per cent). When abnormal, CDS was highly suggestive of rejection, however (45 of 49, 92 per cent specificity). Cyclosporine toxicity was not associated with abnormal pulsatility (zero of seven). In 68 instances, CDS and conventional 99mTc DTPA renogram flow studies were performed together within 24 hours. CDS was more sensitive in detecting rejection but the difference did not reach statistical significance (25 of 36 versus 17 of 36). The major advantage of CDS over conventional radionuclide imaging relates to its shorter examination time, lower cost and portable capabilities. CDS will probably become the roentgenologic imaging modality of choice in renal transplantation.

Color

Computed tomography. Focal and diffuse liver disease.

Contrast enhanced CT is very accurate in the detection of focal hepatic disease. Lesion characterization is a more complex issue, in some instances requiring a combination of CT and other diagnostic tests or biopsy for accurate diagnosis. Although CT remains the modality of choice in the evaluation of suspected focal hepatic disease, this role may change if progress in MR imaging leads to further improvements in lesion detection and characterization.

Contrast Media

Display of CT studies on a two-screen electronic workstation versus a film panel alternator: sensitivity and efficiency among radiologists.

Prototype electronic workstations incorporated in networks linking computed tomographic (CT) and magnetic resonance imaging systems are being developed. The authors compared observer efficiency and sensitivity in reading body CT studies from a two-screen workstation (1,000-line monitors and 12-bit dynamic range in image memory) and conventional film panel alternator. The two-screen workstation displayed 32 images at a matrix resolution of 256 x 256 or eight images at a matrix resolution of 512 x 512 simultaneously. Ninety-six images with a matrix resolution of 512 x 512 could be displayed simultaneously at the film panel alternator. Four observers read images from 20 cases, 10 with repeat examinations, in a randomized viewing sequence. There was an average of 32 images per case. Reporting time was less with the film panel alternator (average, 5.08 minutes) than with the workstation (average, 6.66 minutes). There was improved sensitivity for all observers in reading from the film panel alternator (range, 1%-12%) (P less than .05). In complex cases evaluated by means of body CT, the current prototype two-screen electronic workstation is limited by display capabilities.

Data Display

Color Doppler sonographic imaging in the assessment of upper-extremity deep venous thrombosis.

Color Doppler flow imaging with linear-array transducers was performed in 130 extremities in 91 patients with suspected upper-extremity deep venous thrombosis. Thrombi were detected in 39 studies (30%). Eighty-four patients had either imaging examinations (22 studies comprising venography in 20 patients, CT in one, and MR imaging in one) or clinical follow-up (99 studies) for correlation. In studies with imaging correlation, the sensitivity of the Doppler studies was 78% and the specificity was 92%. There were two false-negative examinations in which the proximal subclavian vein either could not be imaged or the anatomy was distorted. There was one false-positive color Doppler diagnosis of deep venous thrombosis in a case of partial obstruction of the subclavian vein caused by extrinsic compression. There were no known additional errors in color Doppler imaging in patients who had clinical follow-up. Four cases of isolated superior vena cava or proximal innominate vein obstruction were missed by color Doppler imaging. Color Doppler flow imaging is an accurate, noninvasive method for the evaluation of upper-extremity deep venous thrombosis. Other imaging tests may be required when the color Doppler study is negative and central venous thrombosis is suspected.

Adolescent

Color Doppler evaluation of arterial stenoses and occlusions involving the neck and thoracic inlet.

Color Doppler flow imaging is a new technique providing simultaneous display of a gray-scale tissue and a color-flow vascular image. We demonstrate its ability to predict accurately occlusions of numerous vessels, including the internal carotid, external carotid, common carotid, subclavian and innominate arteries. Alterations in flow direction and changes in spectral wave form provide useful clues to the presence of these occlusions. The cases are correlated with angiographic findings and functional flow diagrams of the hemodynamic changes involved.

Arterial Occlusive Diseases

Dynamic hepatic CT.

A technique for incremental dynamic computed tomography (CT) of the liver with boluses of contrast material (with a 50-g iodine load) administered intravenously is described. For most focal liver lesions, which are hypovascular in relation to normal hepatic parenchyma, bolus contrast material enhancement and incremental dynamic scanning improve detectability, compared with that yielded by nondynamic, contrast material infusion techniques. The bolus contrast-enhanced dynamic scan technique is reproducible and of value in patients undergoing sequential CT for assessment of tumor bulk response to chemotherapy. Patients who are potential candidates for resection of focal hepatic lesions should preoperatively undergo intraarterial contrast-enhanced CT. Intravenous bolus enhanced dynamic hepatic CT can be extended to cover more than one anatomic region (eg, abdomen and thorax), as in patients undergoing CT for staging lung carcinoma. In these patients, incremental scan sequences are programmed caudad to cephalad. Incremental dynamic CT is also an appropriate technique to use in cooperative patients who have suffered blunt abdominal trauma.

Contrast Media

Thrombosis at venous insertion sites after inferior vena caval filter placement.

Color Doppler flow imaging or compression ultrasound (US) was used to prospectively determine frequency of thrombosis at 54 venous insertion sites (47 in common femoral veins, seven in right internal jugular veins) after percutaneous placement of Greenfield filters for interruption of the inferior vena cava. Fifty-one filters were successfully placed in 51 patients with a dilator set or a balloon angioplasty catheter. Nine focal thrombi were detected in the common femoral vein (19%) and one in the right internal jugular vein (14%). Use of dilators induced eight thrombi (24%), compared with two (10%) from balloon catheters. The left common femoral vein had a high frequency of thrombosis, regardless of dilation technique (five of nine). Of nine patients with acute common femoral vein thrombosis, four became symptomatic within 10 days after the procedure. Patients may remain asymptomatic or have delayed symptoms; thus, US is valuable for determining patients at risk of thrombosis of the common femoral vein.

Catheterization