Blinded comparison of an "ultrasound stethoscope" and standard echocardiographic instrument

A fully programmable computing architecture for medical ultrasound machines

Application-specific ICs have been traditionally used to support the high computational and data rate requirements in medical ultrasound systems, particularly in receive beamforming. Utilizing the previously developed efficient front-end algorithms, in this paper, we present a simple programmable computing architecture, consisting of a field-programmable gate array (FPGA) and a digital signal processor (DSP), to support core ultrasound signal processing. It was found that 97.3% and 51.8% of the FPGA and DSP resources are, respectively, needed to support all the front-end and back-end processing for B-mode imaging with 64 channels and 120 scanlines per frame at 30 frames/s. These results indicate that this programmable architecture can meet the requirements of low- and medium-level ultrasound machines while providing a flexible platform for supporting the development and deployment of new algorithms and emerging clinical applications.

Use of hand-carried ultrasound devices to augment the accuracy of medical student bedside cardiac diagnoses

BACKGROUND

Hand-carried ultrasound (HCU) devices used by cardiologists as extensions of the physical examination have been shown to improve the accuracy of bedside diagnoses. We tested the feasibility of teaching medical students to use HCU devices to make bedside cardiac diagnoses and compared the accuracy of their HCU and physical examinations.

METHODS

In all, 10 fourth-year medical students enrolled in a 4-week medical school course on the cardiac examination. Students examined 12 standardized patients at 3 different time intervals: (1) on day 1 of the course; (2) on day 10 after review of cardiac physical examination using traditional teaching methods; and (3) after instruction on the use of HCU devices. Students were scored at each time interval for primary findings (most salient) and all findings, accounting for both errors of commission and omission. Scores could range from +12 to -12 for primary findings and from +22 to -22 for all findings. A perfect score was +12 for primary findings and +22 for all findings.

RESULTS

The average score for all students at baseline was -3.2 +/- 3.1 and -5.7 +/- 4.8 for primary and all findings, respectively. A significant improvement in the scores was noted with use of the HCU device (2.6 +/- 3.1 and 5.2 +/- 6.6 for primary and all findings, respectively) compared with the baseline and two subsequent physical examinations.

CONCLUSION

Instruction of fourth-year medical students on the use of HCU device is feasible and results in significantly more accurate bedside diagnoses.

Hand-Carried Ultrasound Improves the Bedside Cardiovascular Examination

OBJECTIVES

We assessed the clinical utility of hand-carried cardiac ultrasound (HCU) devices to assist physicians in the diagnosis of cardiovascular disease.

MATERIALS AND METHODS

We reviewed 42 articles published from 1978 to 2004.

RESULTS

The capability and simplicity of the HCU device assist physicians in the diagnosis of cardiovascular disease at the initial patients contact. HCU is particularly useful in the setting of emergency or critical care, community screening, or in remote areas with limited access to health care.

CONCLUSION

The inherent limitations of the physical examination as well as the reduced focus and training in physical diagnosis of current and recent medical school graduates has set the stage for the HCU device to modify traditional medical practices by complementing the physical examination with real-time cardiovascular imaging.

Influence of hand-carried ultrasound on bedside patient treatment decisions for consultative cardiology

To test the hypothesis that hand-carried ultrasound (HCU) may influence patient treatment on consultative cardiology rounds, 235 patients who were hospitalized (aged 65 +/- 10 years) were studied. First, routine treatment decisions regarding diagnostic workup and therapy were made from patient history, physical examination, 12-lead electrocardiogram, and chart data. Second, a goal-directed HCU study was performed in <10 minutes focusing on left ventricular global and regional function, wall thickness, and presence of pericardial effusion, followed by a reassessment of treatment decisions. HCU data influenced treatment decisions in 149 patients (63%); 50% had a change in medical therapy and 22% had a change in their diagnostic workup (most with changes in both). In all, 12 patients (5%) had an immediate change in the decision for cardiac catheterization or pericardiocentesis. Overall agreement for the above findings with subsequent full-size system echocardiography ranged from 92% to 100% (kappa 0.91-0.96). Goal-directed HCU has the potential to influence bedside patient treatment decisions and expedite health care.

Utility of hand-carried ultrasound for consultative cardiology

Although the stethoscope has been an important part of the bedside cardiac diagnostic examination for generations of physicians, this clinical tool has been relatively unchanged in over 150 years. Echocardiography is established as an essential diagnostic imaging method for patients with known or suspected cardiovascular diseases. However, routine echocardiography systems are large and heavy, and although they are portable, they remain inconvenient for bedside patient rounds. Technologic advances have resulted in miniaturization of electronic components and small, lightweight ultrasound systems have been recently introduced. These hand-carried units offer clinically acceptable two-dimensional image quality for rapid "quick-look" bedside diagnostics, in particular focusing on global and regional left ventricular function and presence or absence of pericardial effusion. This article proposes a general approach to the rapid hand-carried ultrasound cardiac exam as an extension of the physical examination. It details case examples and reviews the initial clinical experience of hand-carried ultrasound on cardiac consultation rounds. Hand-carried ultrasound has promise to have an immediate impact on bedside patient management though expediting and facilitating the delivery of medical care.