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R L Bree

Publications and source records attributed to R L Bree.

At least 19 recordsLinked to original sources
PubMed1995

Automated localization of the prostate at the time of treatment using implanted radiopaque markers: technical feasibility.

PURPOSE: Prostate movement is a major consideration in the formation of target volumes for conformal radiation therapy of prostate cancer. The goal of this study was to determine the technical feasibility of using implanted radiopaque markers and digital imaging to localize the prostate at the time of treatment, thus allowing for reduction of the margin required for uncertainty in target position. METHODS AND MATERIALS: Radiopaque markers implanted around the prostate prior to treatment are visible on electronic radiographs generated with a portal imager or diagnostic imaging device. The locations of the images of these markers on the digital radiographs were automatically determined by a template-matching algorithm. The coordinates of the markers were found by projecting rays through the marker locations on orthogonal radiographs using a three-dimensional (3D) point-matching algorithm. Prostate and/or patient movement was inferred from the marker displacements. Images generated from known movements of a phantom with implanted markers were tested with this algorithm. Locations of markers from daily images of patients with implanted markers were determined by both manual and automatic techniques to determine the efficacy of automated localization on typical clinical images. RESULTS: Prostate movements can be automatically detected in a phantom using low-energy photons within 30 s after image acquisition and with a precision of better than 1 mm in translation and 1 degree in rotation (indistinguishable from the uncertainty in measuring precision). CONCLUSION: The studies show that on-line repositioning of the patient based on localization of the markers at the time of treatment is feasible, and may reduce the uncertainty in prostate location when combined with practical on-line repositioning techniques.

Feasibility Studies↗
PubMed1995

Scintigraphy of incidentally discovered bilateral adrenal masses.

The purpose of this study was to determine the patterns of iodine-131 6 beta-iodomethylnorcholesterol (NP-59) imaging and the correlation with computed tomography (CT)-guided adrenal biopsy and follow-up in patients with bilateral adrenal masses. To this end we investigated a consecutive sample of 29 euadrenal patients with bilateral adrenal masses discovered on CT for reasons other than suspected adrenal disease. Adrenal scintigraphy was performed using 1 mCi of NP-59 injected intravenously, with gamma camera imaging 5-7 days later. In 13 of the 29 patients bilateral adrenal masses were the result of metastatic involvement from lung carcinoma (5), lymphoma (3), adrenocarcinoma of the colon (3), squamous cell carcinoma of the larynx (1), and anaplastic carcinoma of unknown primary (1). Among these cases the NP-59 scan demonstrated either bilaterally absent tracer accumulation (in eight, all with bilateral metastases proven by CT-guided biopsy or progression on follow-up CT) or marked asymmetry of adrenocortical NP-59 uptake (in five). Biopsy of the adrenal demonstrating the least NP-59 uptake documented malignant involvement of that gland in five of five patients. In two patients an adenoma was found simultaneously in one adrenal with a contralateral malignant adrenal mass. In each of these cases, the adenoma demonstrated the greatest NP-59 uptake. In 16 patients diagnosis of adenoma was made on the basis of (a) CT-guided adrenal biopsy of the gland with the greatest NP-59 uptake of the pair (n = 4), or (b) adrenalectomy (n = 2), or (c) absence of change in the size of the adrenal mass on follow-up CT scanning performed 6 months to 3 years later (n = 10).(ABSTRACT TRUNCATED AT 250 WORDS)

Adosterol↗
PubMed1995

Prostate cancer: diagnosis with color Doppler sonography with histologic correlation of each biopsy site.

PURPOSE: To correlate the findings at prostate color Doppler sonography (CDS) with those of site-specific transrectal core biopsy. MATERIALS AND METHODS: Forty-three patients underwent prostate transrectal ultrasonography (US) and biopsy. CDS was performed at all biopsy sites before US-guided core biopsy. Vascularity at CDS was prospectively graded on a scale of 0-2 (0 = no visible peripheral zone [PZ] flow, 2 = markedly increased PZ vascularity). CDS results were correlated with histologic findings from 220 separate biopsy sites that included 27 focal lesions. RESULTS: Of 34 grade 2 biopsy sites, 21 revealed carcinoma, eight revealed prostatitis, and five were negative. CDS depicted at least one focus of carcinoma in seven patients with no gray-scale abnormality. CDS had a sensitivity of 49%, specificity of 93%, and positive predictive value of 62%. CONCLUSION: Focal PZ hypervascularity at CDS is associated with an increased likelihood of prostate cancer or inflammation at biopsy, often without a focal gray-scale abnormality. CDS may help identify an appropriate site for biopsy. A negative CDS scan, however, should not preclude biopsy, as CDS has a limited sensitivity in the detection of all sites of cancer.

Aged↗
PubMed1992

Penetrating atherosclerotic ulcers of the descending thoracic aorta: evaluation with CT and distinction from aortic dissection.

Penetrating atherosclerotic ulceration of the aorta is a poorly understood entity that clinically mimics classic aortic dissection but has imaging features that are distinctly different. In a review of 16 patients with penetrating atherosclerotic ulceration, patients were typically hypertensive (n = 14), and they experienced chest or back pain (n = 13). All patients had an abnormal chest radiograph, with diffuse (n = 14) or focal (n = 2) enlargement of the descending thoracic aorta. Features at contrast material-enhanced computed tomography (CT) included intramural hematoma (n = 16), focal ulcer (n = 15), displaced intimal calcification (n = 13), pleural and/or extrapleural fluid (n = 7), mediastinal fluid (n = 4), and a thick or enhancing aortic wall (n = 6). The chest radiograph and CT findings were compared in patients treated conservatively (n = 9) and surgically (n = 7). These findings did not correlate with the need for surgery. Eight of nine conservatively treated patients were asymptomatic after treatment with antihypertensive medication. Contiguous dynamic contrast-enhanced CT of the aorta enables distinction of ulceration from dissection, which is particularly important in the hemodynamically unstable patient because the surgical management of ulceration is more extensive than that for aortic dissection.

Aged↗
PubMed1992

Focal and diffuse benign hepatic disease: correlative imaging.

With the large numbers of screening CT scans and ultrasounds performed in a busy radiologic practice, it is not uncommon to discover an unexpected focal or diffuse process in the liver. When there is no history of primary malignancy, many of these lesions are benign. We discuss the variety of benign focal and diffuse diseases that can be readily imaged within the liver using ultrasound, CT, and MR.

Cysts↗
PubMed1991

Sonography of large scrotal infections.

We have described 14 cases of large scrotal infections with diffuse involvement of testis and epididymis, thick septations within the cavity, and associated thickening of the scrotal wall and tunica albuginea. The combination of these findings should help distinguish this process from a diffuse neoplastic involvement of the testis where the scrotal wall is almost always of normal thickness. The presence of patchy inhomogenous testicular echo pattern should alert the sonologist to the presence of diffuse suppurative epididymo-orchitis, which may result in necrosis with subsequent orchiectomy in such patients.

Epididymitis↗
PubMed1991

Endorectal sonography in the evaluation of rectal and perirectal disease.

Endorectal sonography initially was developed for evaluation of the prostate and now has been adapted for evaluation of rectal and perirectal disease. We used endorectal sonography to evaluate a spectrum of diseases, including primary and recurrent rectal carcinoma, metastases, villous adenoma, leiomyosarcoma, endometriosis, sacrococcygeal teratoma, chordoma, retroperitoneal cystic hamartoma, pelvic lipomatosis, diverticulitis, and perirectal abscess. The technique has been useful in localization of perirectal abscesses and in sonographically guided biopsy of perirectal masses. Knowledge of normal sonographic anatomy of the rectum is essential in the evaluation of rectal and perirectal disease. In this essay, we describe the technique of endorectal sonography and illustrate the sonographic findings in a variety of diseases.

Abscess↗
PubMed1991

Ultrasonography of liver. Technique and focal and diffuse disease.

Because of its widespread use and availability, ultrasonography is frequently the first test used to assess patients with focal or diffuse hepatic disease. While ultrasonographic features of hepatic lesions often do not allow for a specific diagnosis, this article demonstrates typical ultrasonographic features of commonly encountered disease entities as an aid to differential diagnosis. Recent advances, including Doppler and intraoperative ultrasonography also are discussed.

Humans↗
PubMed1990

Ultrasound of the normal nongravid uterus: correlation with gross and histopathology.

Accurate assessment of uterine size and significance of uterine enlargement are common clinical problems. We examined 156 patients by sonography prior to scheduled hysterectomy. Uterine volumes from normal-sized uteri were calculated from the sonograms using the equation of a prolate ellipsoid formula, and these calculated volumes were highly correlated with actual measured uterine volumes. Mean values and normal ranges of uterine weight were determined. These values are of particular value in postmenopausal patients in whom subjective evaluation of uterine enlargement is often difficult. When a sonographically enlarged, but otherwise normal uterus is discovered, it may contain a leiomyoma or other pathology not morphologically detectable by ultrasound.

Age Factors↗
PubMed1990

Transrectal ultrasound appearance of granulomatous prostatitis.

Granulomatous prostatitis is an uncommon condition that can masquerade as prostatic carcinoma on both digital rectal exam and prostate ultrasound. It occurs most often after acute urinary tract infection, transurethral prostate resection, or needle biopsy. It can be seen in systemic granulomatous diseases and after intravesical bacillus Calmette-Guerin (BCG) therapy for bladder carcinoma. In some cases it is idiopathic. Six patients who underwent transrectal ultrasound of the prostate and subsequent transrectal ultrasound-guided biopsy had histologic diagnosis of granulomatous prostatitis. One patient was undergoing BCG therapy for bladder cancer. Two patients had recent urinary tract infections. The other three patients had no known predisposing conditions. Sonographically, the glands were enlarged in five patients, with multiple large and small hypoechoic zones throughout the peripheral, transition, and central zones. The appearance was similar to that seen in diffuse prostatic carcinoma. In one patient, a solitary hypoechoic lesion in the peripheral zone, indistinguishable from carcinoma, was present. Granulomatous prostatitis should be considered in the differential diagnosis of focal and diffuse abnormality with prostatic ultrasound.

Adult↗
PubMed1989

Advances in pelvic ultrasound: endovaginal scanning for ectopic gestation and graded compression sonography for appendicitis.

Endovaginal sonography and graded compression sonography for appendicitis are two recent, significant advances in the imaging evaluation of the pelvis. Endovaginal sonography is performed by placing a dedicated high-frequency ultrasound probe within the vagina to evaluate the uterus and adnexa. Much early research with this technique has focused on the evaluation of early pregnancy, where changes related to intrauterine and ectopic gestation are evident at least one week earlier when compared with routine transabdominal ultrasound. Graded compression sonography for appendicitis is an ultrasound search for the inflamed, nonruptured appendix performed by compressing the right lower quadrant with a linear array transducer. Both techniques are fast, safe, and inexpensive evaluations that can be used to evaluate patients with nonspecific clinical findings and are particularly helpful in women of childbearing age.

Adult↗
PubMed1989

Computed tomography of chest wall masses.

The authors argue that CT is superior to other imaging techniques for the examination of the bones and soft tissues of the chest wall. They also note the importance of CT in planning therapy for lesions involving these structures. In support of these theses they present computed tomograms showing 26 different types of lesion involving the chest wall ranging from sternal fracture to malignant fibrous histiocytoma. Malignant neoplasms involving the chest wall by metastasis or direct extension from the breast, lung or mediastinum are emphasized.

Humans↗
PubMed1989

Transvaginal sonography in the evaluation of normal early pregnancy: correlation with HCG level.

Transvaginal sonography (TVS) is the procedure of choice in evaluating the viability of embryos early in pregnancy. However, viability based on TVS can be assessed more accurately when the exact gestational age from the last menstrual period is known or when the findings are correlated with beta human chorionic gonadotropin (HCG) levels. No large series has been reported with correlative data between early pregnancy findings, HCG, and gestational age. We performed 75 transvaginal examinations in 53 patients with proved normal pregnancy in the fifth through seventh weeks of gestation. The presence and size of the gestational sac, presence of a yolk sac, and identification of embryonic heart activity were correlated with the level of HCG. Sac size was correlated with yolk sac and heart activity and the three parameters correlated with gestational age in days. When the level of HCG reached 1000 mIU/ml by using the first International Reference Preparation, a gestational sac was seen sonographically in each patient. When the HCG level reached 7200 mIU/ml, a yolk sac was seen in every patient. Ten of 22 patients with HCG between 1000 and 7200 mIU/ml had a visible yolk sac. Every patient with an HCG level greater than 10,800 mIU/ml had a visible embryo with a heartbeat. A discriminatory level of 32 days was found for the presence of a gestational sac. A yolk sac was first seen in every patient between 36 and 40 days. Every patient with accurate dates greater than 40 days had an embryo with a heartbeat identified. When correlating sac size with structures within the sac, a yolk sac was first seen in a gestational sac between 6 and 9 mm and a heartbeat seen in every patient with a 9-mm or greater gestational sac diameter. These data allow identification of normal intrauterine pregnancy and distinction of normal from ectopic gestation at least 1 week earlier than is possible with transabdominal techniques.

Chorionic Gonadotropin↗
PubMed1988

Small renal cell carcinomas: resolving a diagnostic dilemma.

Thirty-nine patients with pathologically proved renal cell carcinomas 3 cm or les in diameter were examined. Results of intravenous urography (n = 30) were true positive in 20 patients and false negative in ten (sensitivity, 67%). Renal ultrasound (US) (n = 29) had true-positive results in 23 patients and false-negative results in six (sensitivity, 79%); computed tomography (CT) (n = 36) had true-positive results in 34 and false-negative results in two (sensitivity, 94%). For selective renal angiography (n = 35%), the results were true positive in 26 and false negative in nine (sensitivity, 74%), with typical hypervascular renal cell carcinomas demonstrated in 17. Finally, the findings of percutaneous fine-needle aspiration biopsy were true positive in one of five patients when US guidance was used (sensitivity, 20%) and in five of eight when CT guidance was used (sensitivity, 62%). Small renal cell carcinomas are more frequently encountered in clinical practice than heretofore realized, and they are best imaged by CT.

Adult↗
PubMed1987

MR imaging of hepatic focal nodular hyperplasia: characterization and distinction from primary malignant hepatic tumors.

Spin-echo MR imaging at 0.35 T was used to image hepatic focal nodular hyperplasia (FNH) and to attempt to distinguish it from primary malignant hepatic tumors. There were six FNH and 10 malignant tumors including seven hepatocellular carcinomas, two cholangiocarcinomas, and one hepatoblastoma. Our results show that FNH has a fairly consistent appearance, dissimilar from that of malignant primary hepatic tumors. Four of six FNH lesions were isointense (except for a central scar in three) and indistinguishable from normal hepatic parenchyma on all pulse sequences, whereas two of six were homogeneous but slightly hyperintense on T2-weighted sequences. Furthermore, a central hyperintense scar was seen in three of six lesions on T2-weighted sequences. In contrast, each of the malignant primary hepatic tumors was hyperintense on T2-weighted sequences and seven of 10 were hypointense on T1-weighted sequences; in nine of 10, heterogeneous areas of intensity were noted. In two fibrolamellar hepatocellular carcinomas a central scar was seen that was hypointense on all pulse sequences. By using quantitative data, the best characterization was obtained by using lesion/normal-liver intensity ratios from a T2-weighted sequence; all FNH had a ratio less than 1.33, while in nine of 10 primary malignant tumors it was greater than 1.41. We conclude that focal nodular hyperplasia may have a consistent appearance on spin-echo MR imaging and probably can be distinguished from primary malignant lesions in most instances.

Adenoma, Bile Duct↗
PubMed1987

The accuracy of CT in the staging of carcinoma of the prostate.

Previous studies have reported the accuracy of CT in distinguishing stages of prostatic carcinoma, but they lack uniform surgical proof of histopathologic stage. We evaluated CT scans in 32 patients who underwent radical prostatectomy to assess its role in the preoperative staging of prostatic carcinoma. Two experienced radiologists blindly interpreted CT scans of the pelvis; they looked for evidence of tumor beyond the prostatic capsule and involvement of the seminal vesicles (stage C) or involvement of pelvic lymph nodes (stage D). Sixty-four interpretations in 32 patients yielded a specificity of 75% for predicting stages A or B disease (local disease), a sensitivity of 50% for the prediction of stages C or D, and an overall accuracy of staging of 67%. Interpretation errors were due to an inability to detect lymph node metastases, errors in evaluating the seminal vesicles, and errors in interpreting densities surrounding the prostate gland. Our data suggest that CT should not be used to influence decisions concerning surgical vs nonsurgical treatment in patients with clinically staged local disease and is only useful when unsuspected metastatic nodal disease is detected.

Diagnostic Errors↗