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R L Bree

Publications and source records attributed to R L Bree.

At least 55 records · Page 3Linked to original sources
PubMed1995

Measurement of prostate movement over the course of routine radiotherapy using implanted markers.

PURPOSE: To measure the range and frequency of occurrence of intertreatment movement of the prostate gland over the course of radiotherapy, and to demonstrate that the prostate may move independently of the surrounding bones of the pelvis. METHODS AND MATERIALS: Ten patients underwent implantation of radiopaque markers around the prostate. Orthogonal portal films were taken at multiple stages during the course of treatment and digitized. An image registration tool was used to solve for film detector placement and, subsequently, to determine positional changes between structures on a reference portal image pair and all subsequent pairs for each patient. Transformations describing prostate movement were measured independently of those describing setup variations of the pelvic girdle. RESULTS: Translation and/or rotation of the prostate was detected in 70% of the treatments for which films were taken. The maximum measured displacement was 7.5 mm along a major axis. Typical translations of the prostate were between 0-4 mm. The translation and rotation had a predominant direction, suggesting a natural axis for prostate movement. CONCLUSION: Although significant prostate displacement can occur between treatments, the typical range of movement seen along a major axis was less than 5 mm. Proper treatment planning should consider the movement of the target independent of surrounding bony anatomy. Advances in online portal imaging, image registration, and dynamic field shaping may permit shaped fields that encompass the prostate gland in its position at the time of treatment, allowing for the use of smaller fields while ensuring proper target coverage.

Humans↗
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↗
PubMed1995

Sonography by the radiologist: self-referral, turf battles, and marketing.

Competition between radiologists and nonradiologists for the performance and billing of radiologic imaging examinations is, perhaps, most pervasive in the field of diagnostic sonography [1-3]. The purpose of this article is to help radiologists understand and deal with turf battles and the self-referral of clinicians and to describe marketing analyses and strategy that can be useful when attempting to decrease competition and increase referrals.

Economic Competition↗
PubMed1994

Magnetization transfer contrast imaging of hepatic neoplasms.

A method of performing magnetization transfer contrast (MTC) using a pulse sequence based on a series of on-resonance binomial pulses preceding a conventional spin-echo sequence has been recently described. We investigated this technique in the evaluation of circumscribed hepatic neoplasms on a 0.5 T imager. Conventional spin-echo imaging was performed in 18 patients with hepatic neoplasms, 15 with primary or metastatic hepatic neoplasms, and 3 with cavernous hemangiomas. The T1-weighted sequence was repeated following MTC saturation in 7 patients and the proton density sequence was repeated following MTC saturation in 13 patients (both were used in two patients). The mean lesion-to-liver contrast for neoplasms worsened with T1-MTC (0.87 vs. 1.04), but improved slightly with proton density-MTC (1.10 vs. 1.22) when compared to the corresponding non-MTC spin-echo images. However, these differences were not statistically significant (p = .19 and p = .16, respectively). The limited data on cavernous hemangiomas does not suggest these have consistently different MTC imaging characteristics from other hepatic neoplasms. In conclusion, MTC imaging using a binomial saturation pulse did not offer significant improvement in contrast between hepatic neoplasms and normal liver. Refinements of the binomial pulse sequence will be necessary if a consistent improvement in lesion sensitivity is to be achieved. Evaluation of its role in increasing diagnostic specificity will require further investigation.

Adenoma↗
PubMed1994

Power Doppler US: a potentially useful alternative to mean frequency-based color Doppler US.

PURPOSE: The authors present a preliminary report to demonstrate a new color Doppler (CD) ultrasonography (US) technique called power Doppler (PD), which displays the total integrated Doppler power in color, and to compare PD with CD imaging, which generally displays an estimate of the mean Doppler frequency shift. MATERIALS AND METHODS: Two standard commercial US scanners that encode the integrated power in the Doppler signal in color were used to demonstrate PD. A standard nonflow-containing US phantom, a normal right kidney, and a torsive and normal contralateral testis were scanned in the power mode. In the phantom and kidney, results with CD and PD were directly compared. RESULTS: PD does not alias, is relatively angle independent, and displays background noise in a way that increases the usable dynamic range of a US scanner. This extended dynamic range should increase machine sensitivity and may demonstrate increased flow in certain circumstances. CONCLUSION: PD is a new CD imaging imaging mode that might be superior to CD in some cases.

Humans↗
PubMed1994

Cost-effective use of low-osmolality contrast media for CT of the liver: evaluation of liver enhancement provided by various doses of iohexol.

OBJECTIVE: Because of pending efforts to reform health care in the United States, judicious use of low-osmolality contrast media is important. We studied the effects of using various concentrations and volumes of iohexol, compared with the conventional dose and concentration of diatrizoate meglumine used for CT, to determine if a more cost-effective dose results in diagnostically efficacious liver enhancement. SUBJECTS AND METHODS: A total of 902 patients received one of nine different doses of IV contrast media. Eight doses of iohexol were used: 125 ml of iohexol 350 (350 mg l/ml, 44 g l/dose), 100 ml of iohexol 350 (35 g l/dose), 150 ml of iohexol 300 (300 mg l/ml, 45 g l/dose), 120 ml of iohexol 300 (36 g l/dose), 100 ml of iohexol 300 (30 g l/dose), 175 ml of iohexol 240 (240 mg l/ml, 42 g l/dose), 150 ml of iohexol 240 (36 g l/dose), and 125 ml of iohexol 240 (30 g l/dose). A single dose (150 ml) of diatrizoate meglumine 60% (w/v) was used (42 g l/dose). Contrast material was injected at a rate of 2 ml/sec. Scanning began 35-45 sec after injection. Quantitative analysis of enhancement was performed by obtaining region-of-interest measurements through the liver on scans obtained before and after injection of contrast material. Mean and maximum changes in hepatic density and mean time to maximum enhancement were measured. Mean time-density curves were subsequently derived for each dose of contrast material. Qualitative analysis of enhancement was performed by using subjective, previously defined criteria. All studies were interpreted in a double-blind fashion. RESULTS: Mean hepatic enhancement was greater with 125 ml of iohexol 350 and 150 ml of iohexol 300 than with other doses of contrast material (p < .05). Both 125 ml of iohexol 350 and 150 ml of iohexol 300 produced actual hepatic enhancement of more than 50 H for over 60 sec. The greatest maximum increase in hepatic density occurred with 125 ml of iohexol 350. When analyzed qualitatively, 150 ml of iohexol 300 resulted in the highest percentage of optimum enhancement. CONCLUSION: According to quantitative analysis, 125 ml of iohexol 350 administered at a rate of 2 ml/sec produces the best enhancement, whereas according to qualitative analysis, 150 ml of iohexol 300 produces the best enhancement. All doses of iohexol 240 provide poor enhancement compared with a conventional dose of contrast material of 150 ml of diatrizoate meglumine 60% or 150 ml of iohexol 300. A moderate cost savings can be achieved by using 125 ml of iohexol 350 for dynamic sequential CT.

Cost-Benefit Analysis↗
PubMed1994

Scintigraphic evaluation of clinically silent adrenal masses.

UNLABELLED: We studied 229 patients with abnormal adrenal anatomy depicted by CT who were without biochemical evidence of endocrine dysfunction using the presence of 131I-6 beta-iodomethyl-nor-cholesterol (NP-59) adrenal gland uptake as an index of differential adrenal function in the evaluation of the clinically "silent" adrenal mass lesion. METHODS: NP-59 (1 mCi) was injected intravenously with posterior and lateral abdominal images obtained 5-7 days postinjection. RESULTS: One-hundred and fifty-nine of 185 patients with unilateral adrenal enlargement on CT had scintigraphic evidence that the mass represented a functioning (NP-59 avid) but not hypersecretory, (biochemically normal) adrenal cortical adenoma (concordant imaging pattern). Forty-one of 44 patients with intra-adrenal neoplasms were depicted on scintigraphy as decreased or absent NP-59 accumulation on the side of the adrenal mass (discordant imaging pattern). In this study, sensitivity was 71% (41 of 58 patients; 95% confidence interval (CI), 58% to 88%); specificity was 100% (171 of 171 patients; 95% CI, 95% to 100%) and accuracy was 93% (212 of 229 patients; 95% CI, 88% to 96%). CONCLUSIONS: These data confirm our earlier observations that the functional information depicted by scintigraphy complements the morphological evaluation by CT and in the absence of hormonal dysfunction, the presence of concordant CT and 131I-NP-59 scans are characteristic of functioning, but not hypersecretory, benign adrenocortical adenomas. Conversely, discordant CT and 131I-NP-59 scans are suggestive of nonfunctioning, space-occupying, adrenal lesions.

Adenoma↗
PubMed1993

Localization of the prostatic apex for radiation therapy using implanted markers.

PURPOSE: This report concentrates on the localization of the prostatic apex using implantable markers, and a comparison to localization defined by computed tomography (CT) and retrograde urethrography. METHODS AND MATERIALS: Fifteen patients were entered into a prospective trial and scheduled to undergo (a) pelvic CT, (b) retrograde urethrogram, and (c) transrectal ultrasound with placement of radiodense markers. Three markers were implanted: one was placed at the trapezoid area (prostatic apex), and the others placed lateral to the base of each seminal vesicle. The retrograde urethrogram was performed using standard technique. The superior-inferior distance between the apex identified by the marker placed at the prostatic apex and the other studies was measured. RESULTS: CT and urethrogram overestimated the inferior extent of the prostatic apex when compared to the location as defined by the implanted marker. With CT, the average distance from the marker to the CT-defined apex was 0.6 cm (95% C.I.--0.4-0.8 cm). With urethrogram, the average distance from the marker to the urethrogram-defined apex was 1.3 cm (95% C.I.--0.7-1.9 cm). When CT and urethrogram were compared, CT was more accurate in identifying the prostatic apex. CONCLUSION: Under ultrasound guidance, radiodense markers have been implanted into the prostate. This has revealed that the apex is localized superior to the apical margin as defined by retrograde urethrogram and CT, and that CT may be more accurate than retrograde urethrogram. In addition, the placement of multiple markers yields spatial information on prostatic position that can be extracted from megavoltage portal images.

Adenocarcinoma↗
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↗