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Biomedical subjects

R B Jeffrey

Publications and source records attributed to R B Jeffrey.

At least 55 records · Page 3Linked to original sources
PubMed1997

Power versus color Doppler sonography of the normal cystic artery: implications for patients with acute cholecystitis.

OBJECTIVE: The purposes of this investigation were to compare prospectively the pattern and extent of cystic artery flow revealed by power Doppler sonography and color Doppler sonography in patients with normal gallbladders and to analyze the potential implications of these findings for power Doppler sonography in diagnosing acute cholecystitis. SUBJECTS AND METHODS: The cystic arteries of 142 patients (79 women and 63 men) with normal gallbladders were imaged with both power Doppler sonography and color Doppler sonography using 5-MHz transducers and settings optimized to reveal low-volume flow. The presence or absence of cystic artery flow and the anatomic extent of its visualization were recorded for each patient. RESULTS: Power Doppler sonography revealed flow in 73% of patients with normal gallbladders compared with 53% revealed by color Doppler sonography. Cystic artery flow within the distal fundal quartile was revealed by power Doppler sonography in 20% of patients and flow spanning greater than 50% of the anterior gallbladder wall was revealed by power Doppler sonography in 17% of patients. These findings differed from those of color Doppler sonography at a highly significant level (p < .0001, chi-square test). CONCLUSIONS: Power Doppler sonography is significantly more sensitive than color Doppler sonography for revealing cystic artery flow in patients with normal gallbladders. The flow patterns in patients with normal gallbladders obtained with power Doppler sonography overlap flow patterns previously reported as fairly specific criteria for diagnosing acute cholecystitis using color Doppler sonography, namely, flow within the distal fundal quartile and flow spanning greater than 50% of the anterior gallbladder wall. Accordingly, these color Doppler sonography criteria are not applicable to the diagnosis of acute cholecystitis with power Doppler sonography. Different power Doppler sonography criteria are necessary for the diagnosis of acute cholecystitis.

Acute Disease↗
PubMed1997

Renal hypoperfusion: value of power Doppler imaging.

The improved depiction of renal parenchymal vascularity with power Doppler imaging facilitates the sonographic detection of hypovascular lesions such as pyelonephritis, renal abscesses, and infarction. However, the finding of diminished or absent lobar perfusion may be present in all of these entities; thus, the abnormalities shown on power Doppler imaging are often nonspecific. Clinical and laboratory data are often essential to establish the correct diagnoses. Contrast-enhanced CT remains useful for distinguishing these various disorders.

Adult↗
PubMed1997

Preliminary experience with power Doppler imaging of solid breast masses.

OBJECTIVE: The purpose of our study was to assess the potential of power Doppler imaging (PDI) to differentiate benign from malignant solid breast masses. MATERIALS AND METHODS: Sixty-nine biopsy-proven solid breast masses were evaluated with PDI using 7- to 10-MHz transducers optimized for low-volume flow sensitivity. The extent of flow on PDI was estimated as a percentage of the lesion area on multiple longitudinal and transverse static sonographic images. Flow was categorized as avascular; less than 10%; 10-25%; 25.1-50%; and greater than 50%. RESULTS: Of the 69 lesions evaluated, 33 were malignant and 36 were benign. Of the avascular lesions, nine were malignant and eight were benign. Significant overlap was seen in the vascularity of the other 52 lesions: both malignant and benign lesions revealed a similar range of vascular patterns. CONCLUSION: Preliminary experience with PDI suggests that both malignant and benign lesions can be avascular and that the presence of color within a solid breast mass is a nonspecific finding. Assessing the extent of vascularity with PDI appears to be of limited value in the diagnostic evaluation of solid breast masses.

Adult↗
PubMed1997

Acalculous cholecystitis in patients undergoing bone marrow transplantation.

OBJECTIVE: To evaluate factors associated with acalculous cholecystitis in patients undergoing bone marrow transplantation and the role of repeat ultrasound examinations. DESIGN: Retrospective study. SETTING: University hospital, United States. SUBJECTS: 381 Patients who underwent bone marrow transplantation between 1987 and 1992. INTERVENTIONS: Abdominal ultrasound examination (n = 134), repeat ultrasound in those considered to have acalculous cholecystitis (n = 8), and acute cholecystectomy (n = 5). RESULTS: 14 Patients (4%) with acalculous cholecystitis were identified. The 8 who had had liver tissue examined also had veno-occlusive disease of the liver. It was possible to follow progressing or resolving acalculous cholecystitis by repeat ultrasound examinations. 4 Of the 5 patients treated surgically survived, compared with 3 of the 9 not operated on. CONCLUSIONS: Acalculous cholecystitis was associated with veno-occlusive disease of the liver. Repeat ultrasound examinations were valuable in showing progressing or resolving acalculous cholecystitis and may guide treatment. Cholecystectomy seems to be a safe procedure for acalculous cholecystitis in patients undergoing bone marrow transplantation.

Adult↗
PubMed1996

Diagnosis of pancreatic injury after blunt abdominal trauma.

Expeditious diagnosis and treatment of pancreatic injury continues to elude the trauma surgeon and radiologist. Missed or underestimated pancreatic injury is responsible for a high level of morbidity and mortality after blunt or penetrating trauma. Unfortunately, inappropriate therapy can lead to devastating consequences such as severe endocrine or exocrine insufficiency. Abdominal CT is currently the imaging method of choice for evaluating patients with blunt trauma. This article reviews the constellation of CT findings that the radiologist must rely on to establish the diagnosis of pancreatic injury.

Abdominal Injuries↗
PubMed1996

Perspective volume rendering of CT and MR images: applications for endoscopic imaging.

PURPOSE: To use perspective volume rendering (PVR) of computed tomographic (CT) and magnetic resonance (MR) imaging data sets to simulate endoscopic views of human organ systems. MATERIALS AND METHODS: Perspective views of helical CT and MR images were reconstructed from the data, and tissues were classified by assigning color and opacity based on their CT attenuation or MR signal intensity. "Flight paths" were constructed through anatomic regions by defining key views along a spline path. Twelve movies of the thoracic aorta (n=3), tracheobronchial tree (n=4), colon (n=3), paranasal sinuses (n=1), and shoulder joint (n=1) were generated to display images along the flight path. All abnormal results were confirmed at surgery. RESULTS: PVR fly-through enabled evaluation of the full range of tissue densities, signal intensities, and their three-dimensional spatial relationships. CONCLUSION: PVR is a novel way to present volumetric data and may enable noninvasive diagnostic endoscopy and provide an alternate method to analyze volumetric imaging data for primary diagnosis.

Aorta, Thoracic↗
PubMed1996

Screening for deep venous thrombosis in asymptomatic postoperative orthopedic patients using color Doppler sonography: analysis of prevalence and risk factors.

OBJECTIVE: The purpose of our study was to assess the prevalence and risk factors for sonographically detectable lower extremity deep venous thrombosis (DVT) in asymptomatic patients following major orthopedic surgery. SUBJECTS AND METHODS: We performed color Doppler sonography of the lower extremities in 474 asymptomatic patients following major hip or knee surgery. We determined the prevalence of lower extremity DVT and used stepwise logistic regression to identify factors predictive of DVT. All patients received routine prophylactic measures. RESULTS: The prevalence of DVT was 7%. Laterality of surgery, age, and gender were all independent predictors of DVT (p < or = .01): the odds of having DVT were 20 times higher in the leg that was operated upon than in the leg that was not; the odds of DVT rose by a factor of 1.5 per decade of life; and the odds of DVT were 3.4 times greater in men than in women. DVT was more common in patients who had received general rather than epidural anesthesia, with borderline significance (p = .06). The length of anesthesia and the joint involved (hip or knee) were not predictive of DVT (p > .10). CONCLUSION: Despite prophylaxis, DVT is a relatively common postoperative complication in patients who undergo major orthopedic procedures. Routine screening for DVT is warranted in asymptomatic patients who have undergone hip or knee surgery, and color Doppler sonography, despite its limitations, offers a reasonably accurate noninvasive method for screening these patients. Subsets of patients who are at particular risk include the elderly, male patients, and patients who have undergone general anesthesia. The low prevalence of DVT in limbs not operated upon suggests that routine screening may be limited to evaluating the affected limbs only, thus helping to minimize the cost of screening.

Aged↗
PubMed1996

Normal variations in the lateral contour of the head and neck of the pancreas mimicking neoplasm: evaluation with dual-phase helical CT.

OBJECTIVE: The purpose of this study was to analyze variations in the lateral contour of the head and neck of the pancreas that can mimic pancreatic masses on CT imaging. MATERIALS AND METHODS: We retrospectively reviewed dual-phase helical CT examinations of 119 patients who had no clinical or CT evidence of pancreatic disease. Contour variations of the head and neck of the pancreas were analyzed and were classified according to their anatomic orientation. RESULTS: Forty-one (34.5%) of the 119 patients had discrete lobulations of pancreatic tissue greater than 1 cm lateral to the gastroduodenal or anterior superior pancreaticoduodenal artery. These lobulations showed normal pancreatic density on both predominantly arterial and portal venous phase images. Contour variants of the pancreatic head and neck were categorized as three main types: anterior (type I), posterior (type II), and horizontal (type III). In the 119 patients, we found 12 type I variants (10%), 23 type II variants (19%), and six type III variants (5%). CONCLUSION: Variations in the lateral contour of the normal head and neck of the pancreas are common. Recognition of the different types of contours may help avoid misinterpretation of normal variants as pancreatic masses.

Adolescent↗
PubMed1996

Power Doppler imaging of focal lesions of the gastrointestinal tract: comparison with conventional color Doppler imaging.

To compare the usefulness of power Doppler imaging and color Doppler imaging in the vascular evaluation of gastrointestinal lesions, 21 patients with focal gastrointestinal tract lesions were examined with both power and color Doppler imaging. Two reviewers blinded to the diagnosis compared intramural vascularity detected by each of these methods. Power Doppler imaging detected flow in 16 patients with nonischemic lesions, whereas color Doppler imaging detected flow in only 11 patients. Neither modality detected flow in three patients with transmural infarction, but only power Doppler imaging detected minimal flow in the two patients with reversible ischemia. Power Doppler imaging improves visualization of intramural gastrointestinal vascularity, increasing the level of confidence in differentiating ischemic from nonischemic lesions.

Adult↗
PubMed1995

Degenerated uterine leiomyoma mimicking acute appendicitis: sonographic diagnosis.

The present study reviews four cases in which degenerated uterine leiomyomas mimicked appendicitis clinically. The correct diagnosis was made prospectively by sonography in each case. Appendicitis was excluded by graded compression sonography and an exophytic uterine leiomyoma was identified at the point of maximal symptoms. The leiomyomas demonstrated central hypoechoic foci, but no detectable Doppler flow indicating necrosis. Although the phenomenon of a degenerated uterine leiomyoma mimicking appendicitis clinically is known, sonographic diagnosis has not been reported previously. The importance of making this diagnosis sonographically is that management of a degenerated leiomyoma is conservative and unnecessary surgery could be avoided.

Acute Disease↗
PubMed1995

CT of blunt trauma to the bowel and mesentery.

Injuries to the bowel and mesentery are found in approximately 5% of all patients undergoing laparotomy after blunt abdominal trauma. Bowel and mesenteric injuries are often subtle and difficult to diagnose, and a delay in the diagnosis is associated with increased mortality and morbidity. CT is the best imaging method for diagnosing injuries to the bowel and mesentery. With meticulous scanning techniques, most significant bowel and mesenteric injuries can be reliably identified with CT preoperatively, and associated injuries to other abdominal viscera can be confirmed.

Colon↗
PubMed1995

Magnetic resonance imaging and hepatic hemodynamics: correlation with metabolic function in liver transplantation candidates.

BACKGROUND: Preoperative assessment of orthotopic liver transplantation candidates requires definition of both the anatomy and metabolic function of the native liver. Current evaluation techniques combine computed tomographic scanning, duplex ultrasonography with blood chemistry analysis, and physical stigmata of end-stage liver disease. Recently, magnetic resonance imaging (MRI) has emerged as an alternative method for delineation of hepatic and portal venous anatomy. In addition, MRI accurately measures hepatic volume and portal venous blood flow. METHODS: To examine the role of MRI-derived indexes of hepatic hemodynamics in the preoperative assessment of liver function, 39 consecutive liver transplantation candidates were studied in a prospective manner. Liver function (aspartate aminotransferase), alanine aminotransferase, alkaline phosphatase, total bilirubin, and albumin levels), hematologic indexes (complete blood cell count, prothrombin time), and Child's classification were determined at the time of evaluation. Axial breath-held multiplanar spoiled-gradient echo MRI measured hepatic volume, whereas a cine phase-contrast sequence perpendicular to the portal vein measured flow. RESULTS: Hepatic index, defined as hepatic mass corrected for body surface area, was found to correlate with prothrombin time (p < 0.04) and platelet count (p < 0.03) by multivariate regression analysis. Portal flow index (PFI), defined as portal flow corrected for hepatic mass), was associated with aspartate aminotransferase (p < 0.02), alanine aminotransferase (p < 0.04), and albumin (p < 0.03) by multivariate regression analysis. In addition, PFI was closely correlated with the patients' functional status as determined by Child's classification system. Increasing values of PFI were associated with declining hepatic functional reserve. Child's class A patients had a mean PFI that was two times less than that of Child's class B patients (0.26 +/- 0.04 versus 0.04 +/- 0.06 ml/min/gm; p < 0.02) and five times less than that of Child's class C patients (0.26 +/- 0.04 versus 1.05 +/- 0.14 ml/min/gm; p < 0.001). Similarly, the mean PFI associated with Child's class B was two times less than that of Child's class C (0.46 +/- 0.06 versus 1.05 +/- 0.14 ml/min/gm; p < 0.01). These data show that MRI-derived indexes of portal hemodynamics and hepatic mass (1) correlate well with biochemical indexes of hepatic dysfunction and (2) serve as anatomic and hemodynamic correlates to Child's functional classification. CONCLUSIONS: We conclude that MRI may serve to noninvasively delineate preoperative hepatic vascular anatomy and metabolic dysfunction in candidates undergoing examination for liver transplantation.

Adult↗
PubMed1995

Quantitative evaluation of pancreatic enhancement during dual-phase helical CT.

PURPOSE: To determine the improvement in pancreatic enhancement at helical computed tomography (CT) performed with an early delay after administration of contrast material compared with that performed with a standard delay. MATERIALS AND METHODS: Dual-phase helical CT of the abdomen was performed in 120 patients with a 150-mL bolus of contrast material infused at 5 mL/sec. Early and standard delayed scanning was performed beginning at 20 seconds and 49-71 seconds, respectively. Regions of interest were measured in the head, body, and tail of the pancreas in 92 patients. The difference in enhancement between early and standard delayed scanning was calculated. RESULTS: Mean pancreatic enhancement was 82 HU +/- 3 (standard error) with an early delay, whereas enhancement on standard delay scans was 62 HU +/- 2 (P < .001). An improvement in enhancement greater than 10 HU was attained in 66 of 92 cases (72%). CONCLUSION: Pancreatic enhancement at helical CT with an early delay after contrast material administration is often significantly greater than the enhancement seen with a standard delay when a monophasic, rapidly infused bolus of contrast material is used.

Abdominal Neoplasms↗
PubMed1995

Assessment of living renal donors with spiral CT.

PURPOSE: To determine whether spiral computed tomography (CT) can be used to evaluate potential living renal donors. MATERIALS AND METHODS: Twelve potential living renal donors underwent spiral CT and conventional arteriography. CT angiography was performed with 30-second spiral acquisition during injection of 150 mL of nonionic iodinated contrast material into an antecubital vein at 5 mL/sec. Five minutes after injection, a frontal abdominal scout projection was obtained to assess the renal collecting system. Results of blinded interpretations of axial CT angiograms, three-dimensional CT angiograms, and conventional arteriograms were correlated with intraoperative findings in 11 cases. RESULTS: Axial and three-dimensional CT angiography were 100% sensitive for identifying seven accessory renal arteries and 14% and 93% sensitive for identifying five prehilar renal artery branches. Renal venous anomalies were confirmed in three patients at surgery. Operative management changed in four of 11 patients who underwent donor nephrectomy. CONCLUSION: Spiral CT holds promise as a single examination for anatomic assessment of living renal donors.

Adult↗
PubMed1995

Lymphoma and leukemia involving the testicles: findings on gray-scale and color Doppler sonography.

OBJECTIVE: The purpose of this study was to determine the gray-scale and color Doppler sonographic appearance of testicular lymphoma and leukemia to aid in its differentiation from primary testicular neoplasms and inflammatory processes. MATERIALS AND METHODS: We retrospectively reviewed the testicular sonograms of eight male patients 5-74 years old (mean age, 43 years) with pathologically proved testicular leukemia or lymphoma. All patients presented with testicular enlargement. Gray-scale sonograms were obtained to determine the presence or absence of a mass, focal nodule, or diffuse infiltration, as well as the degree of parenchymal echogenicity. Color Doppler sonography was applied in each case to determine the degree of vascularity compared with normal ipsilateral or contralateral testicular parenchyma. In patients with focal, measurable lesions, the size was correlated with its color Doppler sonographic appearance. RESULTS: Gray-scale sonograms showed either homogeneously hypoechoic testes in patients with diffuse round-cell infiltration or multifocal hypoechoic lesions of various sizes. Five patients had a total of 11 focal lesions that ranged in size from 8 mm to 26 mm in maximum diameter (mean diameter, 16 mm). Color Doppler sonography revealed increased intralesional flow in all areas of lymphomatous or leukemic involvement irrespective of lesion size. CONCLUSION: Our results show that testicular lymphoma and leukemia are hypervascular on color Doppler sonograms regardless of the size of the tumor. Although color Doppler sonography may provide useful information, differentiating round-cell infiltration from inflammatory processes of the testes remains difficult.

Adolescent↗