Doppler Appearance Research Articles

The transcranial doppler appearance of acute carotid artery occlusion

Transcranial Doppler ultrasound is a noninvasive technique of cerebral blood velocity measurement that is being increasingly used to detect untoward hemodynamic changes. In this report, we describe striking transcranial Doppler ultrasound changes occurring in 2 patients after cervical carotid artery occlusion that led to cerebral infarction. These changes consist of the sudden appearance of a Doppler signal of extremely low pulsatility and moderately high velocity in the middle cerebral artery distribution. In 1 patient, this signal was the first sign of carotid occlusion. We suggest that these transcranial Doppler ultrasound changes can provide an early warning of carotid artery compromise.

Duplex and color Doppler appearance of isolated internal iliac aneurysm

Duplex and color Doppler appearance of isolated internal iliac aneurysm

Unusual Pulmonic Regurgitant Jet on Color Flow Doppler

We describe the color flow Doppler appearances of an unusually directed jet of pulmonic valve regurgitation in a patient who has had surgery for aortic root dissection. This jet was bluish on color flow Doppler (away from transducer) and diastolic in timing, with peak velocity 1.8 m/sec; it originated at the point of apposition of the pulmonic cusps. These features served to distinguish the jet from that due to an iatrogenic aortic root-right ventricular fistula. We speculate that the pulmonary trunk was so distorted during surgery on the ascending aorta as to alter alignment of the pulmonic valve cusps, resulting in the unusual direction of the regurgitant jet.

Case report: The ultrasound and doppler appearances of pelvic varices

Dilatation of the veins of the broad ligament and ovarian plexi cause a very specific clinical entity called the pelvic congestion or pelvic pain syndrome. The ultrasound and Doppler appearances of this condition are unique and should be easily recognized. We describe these appearances in one patient and review the literature.

Color Doppler ultrasound of the normal testis

Color Doppler ultrasound with point spectral analysis was performed on 30 testes of 15 asymptomatic volunteers. Intratesticular arteries and testicular capsular arteries were imaged in all 30 cases. Waveforms from these vessels were similar and consistently showed a low-impedance pattern with high levels of diastolic flow. This reflects the low vascular resistance of the testis. Supratesticular arteries were also identified in all 30 cases. In addition to the low-impedance-type waveforms from the testicular artery, waveforms obtained in the supratesticular region also originated from the deferential and/or cremasteric arteries. This resulted in some waveforms with high-impedance patterns, reflecting the high vascular resistance of the epididymis and peritesticular tissues. We believe that color Doppler ultrasound is capable of reliably showing the normal testicular arterial anatomy by imaging intraarterial blood flow. Knowledge of the normal color Doppler appearance and waveform characteristics of the testicular artery should aid in diagnosing scrotal conditions that alter blood flow.

Doppler echocardiography appearance of cusp tears in tissue valve prostheses

Characteristic Doppler echocardiographic abnormalities were noted in five patients with a failing tissue prosthesis shown to have severe regurgitation and no evidence of obstruction. The audio signal was musical in quality and the regurgitant flow pattern was bidirectional and striated. There were 4 to 6 striations in the mitral and 18 in the aortic regurgitant jets per 100 cm/s length of signal. Pulsed Doppler ultrasound localized the jet to the valve in all cases although angiography failed to localize it in one of four cases. At surgery each valve had a tear in or partial disintegration of one cusp whereas the other two cusps were intact, mobile and of normal thickness. The Doppler appearance is thought to be caused by fluttering of the disrupted cusp leading to the shedding of families of vortices in both a retrograde and an orthograde direction. It is suggested that this is likely to be a useful sign for the diagnosis of cusp tears.