Search PubMed⌕ Search

Biomedical subjects

Deborah J Rubens

Publications and source records attributed to Deborah J Rubens.

26 records · Page 2Linked to original sources
PubMed2003

Randomized prospective study comparing routine versus selective use of sonography of the complete calf in patients with suspected deep venous thrombosis.

OBJECTIVE: We compared patient outcomes using two protocols: one routinely and the other selectively evaluating the calves completely during sonographic assessment of the lower extremities in patients with suspected deep venous thrombosis. SUBJECTS AND METHODS: In this randomized prospective study, patients were assigned to two groups. In one group, the deep calf veins were routinely evaluated in their entirety, and in the other group the calf was not evaluated unless the patient had symptoms or physical signs in the calf, in which case only the areas of symptoms or physical signs were evaluated. Patients were followed up for 3 months by medical record review, physician surveys, and telephone calls. An adverse outcome was a propagated deep venous thrombosis into the thigh or a pulmonary embolus. Examination times were recorded when possible. RESULTS: Of the 235 patients in the group in which the deep calf veins were routinely evaluated, we saw no adverse outcomes (0.0%; 97.5% one-sided confidence interval [CI], 0.6-1.6%). Of the 261 patients in the group in which the calf was only evaluated if there were signs or symptoms, we saw two adverse outcomes (0.8%; 95% CI, 0.1-2.7%). CONCLUSION: We found no significant difference in adverse outcomes in patients undergoing a protocol in which the deep calf veins were routinely evaluated or a protocol in which the calf was evaluated only if physical signs or symptoms were present.

Adult↗
PubMed2003

Treated needles: do they facilitate sonographically guided biopsies?

OBJECTIVE: We sought to compare needle visualization and diagnostic yield rates resulting from the use of several commercially available treated needles in sonographically guided biopsies. METHODS: We conducted a randomized prospective study in which 61 patients (42 women and 19 men; mean age, 57 years; range, 19-84 years) were assigned to undergo biopsies (37 thyroid and 24 liver, 2 passes per patient) with 1 of 4 different 22-gauge needles: Teflon coated, etched tip, echogenic polymer coated, and untreated. Two blinded radiologists independently scored needle shaft and tip visualization from 0 (no visualization) to 4 (excellent visualization). After blinded cytologic evaluation, the individual passes were rated as adequate or inadequate for establishing a tissue diagnosis. RESULTS: The echogenic polymer-coated needle had the highest mean score +/- SD for visualization of both the shaft (3.4 +/- 0.90) and tip (3.5 +/- 0.87) compared with the untreated (shaft, 2.2 +/- 0.77; P = 0.003; tip, 2.8 +/- 0.92; P = 0.01), Teflon-coated (shaft, 2.7 +/- 0.94; tip, 3.1 +/- 0.75), and etched tip (shaft, 3.0 +/- 0.82; tip, 3.0 +/- 0.56) needles. Diagnostic yield rates for the 4 different needle types were 75.0% for the echogenic polymer-coated, 64.7% for the Teflon-coated, 56.3% for the etched tip, and 75.0% for the untreated needles (no significant difference). CONCLUSIONS: The echogenic polymer-coated needle was the best visualized of all needles evaluated, both treated and untreated. No significant difference was found in diagnostic yield rates, but that may be reflective of the relatively small sample size.

Adult↗
PubMed2002

Shear wave focusing for three-dimensional sonoelastography.

A new vibration scheme is shown to provide localized vibration fields for three-dimensional sonoelastography imaging. The theoretical vibration distributions of double strip loads vibrating normally to the surface of a semi-infinite elastic space are calculated. A localization or focusing of shear waves inbetween the double-strip loads is predicted. Experimentally, two parallel rigid rectangular cross-section bars are mounted on an electromagnetic shaker. Driven by the signal source, the bars vibrate against the surface of a tissue-mimicking phantom. The double-bar source is also used to propagate shear wave into an ex vivo prostate phantom with a 6 mm "tumor" in it. A combination of high frequencies (400-600 Hz) is used to drive the double-bar applicator. In the phantom experiments, a shear wave focal zone with higher vibration amplitude and uniformity predicted by the theory was confirmed. The position of the focal zone is controllable when adjusting the separation of the bars as the theory shows. When this vibration scheme was used in a prostate phantom experiment, high-resolution tumor images with clear boundaries are obtained. The parallel bar is an ideal applicator to create more uniform vibration within a controllable localized volume. The field has uniformity especially in the direction along the bars.

Culture Techniques↗
PubMed2002

Detection and diagnosis of nonpalpable supraclavicular lymph nodes in lung cancer at CT and US.

PURPOSE: To assess frequency and significance of enlarged nonpalpable supraclavicular lymph nodes by using chest computed tomography (CT) and supraclavicular ultrasonography (US) in patients at initial diagnosis of lung cancer. MATERIALS AND METHODS: Fifty-five patients with no prior malignancy who presented with suspected and subsequently proven lung cancer of any stage or a proven but potentially resectable lung cancer were prospectively selected after chest CT. Chest CT and other radiologic findings were reviewed and tabulated. Standardized US technique was used to identify and guide needle biopsy of enlarged supraclavicular lymph nodes (> or =0.5 cm short axis). RESULTS: Twenty-two (40%) of 55 patients had supraclavicular abnormalities detected at CT and/or US. In 18 (82%) of the 22 patients, supraclavicular abnormalities were recognizable at CT. Seventeen of 22 patients had malignant nodes, and five patients had benign nodes (n = 3), a cyst (n = 1), or an indeterminate lesion (n = 1) at US-guided supraclavicular needle sampling. There were no complications. Supraclavicular metastases (31% of patients) were about as common as the combined number of patients with indeterminate (n = 13) and probably or proven malignant (n = 6) adrenal nodules (35% of patients). Supraclavicular metastases were often associated with mediastinal adenopathy or suspected extrapulmonary nonnodal metastases (P <.05). CONCLUSION: In many patients with lung cancer, chest CT that includes the neck base followed by US-guided sampling of enlarged supraclavicular lymph nodes is a simple and safe method for simultaneously establishing a tissue diagnosis and tumor nonresectability.

Adult↗
PubMedDate not supplied

Slow flow or no flow? Color and power Doppler US pitfalls in the abdomen and pelvis.

Color and power Doppler ultrasonography allow rapid assessment of tissue vascularity. Motion sensitivity to phenomena such as flow along the edge of gallstones, urinary jets, and placentation abnormalities can result in artifactual flow patterns that require corroboration with spectral analysis. Similar artifacts have also been noted at the edge of bone and along the bowel wall secondary to bowel motion. These artifacts fall into four categories: (a) twinkle artifacts, which occur behind reflectors; (b) edge artifacts, which occur along strongly reflective interfaces; (c) flash artifacts, which occur due to tissue or fluid motion; and (d) pseudoflow, which occurs due to nonvascular flow of other fluids such as urine or ascites. Knowledge of the most common sites of color and power Doppler artifacts, familiarity with the typical appearances of these artifacts, and liberal use of spectral analysis will help prevent misinterpretation of these findings and may lead to improved diagnostic accuracy.

Abdomen↗
PubMedDate not supplied

Endoluminal management of arterioportal fistulae in liver transplant recipients: a single-center experience.

Transcatheter embolization of arterioportal fistulae in liver transplant recipients is restricted to symptomatic arterioportal fistulae. Angiograms of liver transplant recipients from a single university medical center were retrospectively reviewed. Hemodynamically significant arterioportal fistulae were defined as those exhibiting opacification of the main portal vein of the transplanted hepatic graft or its first order branch with or without portal venous changes by Doppler ultrasound imaging. Six arterioportal fistulae were found. Doppler ultrasound imaging detected 50% of all arterioportal fistulae and all 3 hemodynamically significant arterioportal fistulae. Three successful embolizations were performed. Follow-up (37 to 67 months) demonstrated patent hepatic arteries and no parenchymal ischemic changes with graft preservation. High-throughput arterioportal fistulae may require larger intrahepatic artery branch embolization. There is a window of opportunity for embolizing significant arterioportal fistulae before their progression to large symptomatic, high through-put arterioportal fistulae with their added risk of ischemic changes before and after embolization.

Adolescent↗