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International Journal of Radiation Oncology Biology Physics | 1995

Tumor perfusion studies using fast magnetic resonance imaging technique in advanced cervical cancer: A new noninvasive predictive assay

Nina A. Mayr; William T. C. Yuh; Vincent A. Magnotta; James C. Ehrhardt; James A. Wheeler; Joel I. Sorosky; Charles S. Davis; B.-Chen Wen; Douglas Martin; Retta E. Pelsang; Richard E. Buller; Larry W. Oberley; David E. Mellenberg; David H. Hussey

PURPOSE This study investigated sequential changes in tumor blood supply using magnetic resonance (MR) perfusion imaging and assessed their significance in the prediction of outcome of patients with advanced cervical cancer. The purpose of this project was to devise a simple, noninvasive method to predict early signs of treatment failure in advanced cervical cancer treated with conventional radiation therapy. METHODS AND MATERIALS Sixty-eight MR perfusion studies were performed prospectively in 17 patients with squamous carcinomas (14) and adenocarcinomas (3) of the cervix, Stages bulky IB (1), IIB (5), IIIA (1), IIIB (8), and IVA (1), and recurrent (1). Four sequential studies were obtained in each patient: immediately before radiation therapy (pretherapy), after a dose of 20-22 Gy/ approximately 2 weeks (early therapy), after a dose of 40-45 Gy/ approximately 4-5 weeks (midtherapy), and 4-6 weeks after completion of therapy (follow-up). Perfusion imaging of the tumor was obtained at 3-s intervals in the sagittal plane. A bolus of 0.1 mmol/kg of MR contrast material (gadoteridol) was injected intravenously 30 s after beginning image acquisition at a rate of 9 ml/s using a power injector. Time/signal-intensity curves to reflect the onset, slope, and relative signal intensity (rSI) of contrast enhancement in the tumor region were generated. Median follow-up was 8 months (range 3-18 months). RESULTS Tumors with a higher tissue perfusion (rSI > or = 2.8) in the pretherapy and early therapy (20-22 Gy) studies had a lower incidence of local recurrence than those with a rSI of < 2.8, but this was not statistically significant (13% vs. 67%; p = 0.05). An increase in tumor perfusion early during therapy (20-22 Gy), particularly to an rSI of > or = 2.8, was the strongest predictor of local recurrence (0% vs. 78%; p = 0.002). However, pelvic examination during early therapy (20-22 Gy) commonly showed no appreciable tumor regression. The slope of the time/signal-intensity curve obtained before and during radiation therapy also correlated with local recurrence. Follow-up perfusion studies did not provide information to predict recurrence. CONCLUSION These preliminary results suggest that two simple MR perfusion studies before and early in therapy can offer important information on treatment outcome within the first 2 weeks of radiation therapy before response is evident by clinical examination. High tumor perfusion before therapy and increasing or persistent high perfusion early during the course of therapy appear to be favorable signs. High perfusion suggests a high blood and oxygen supply to the tumor. The increase in tumor perfusion seen in some patients early during radiation therapy suggests improved oxygenation of previously hypoxic cells following early cell kill. Radiation therapy is more effective in eradicating these tumors, resulting in improved local control. Our technique may be helpful in identifying early-while more aggressive therapy can still be implemented-those patients who respond poorly to conventional radiation therapy.


International Journal of Radiation Oncology Biology Physics | 1995

Usefulness of tumor volumetry by magnetic resonance imaging in assessing response to radiation therapy in carcinoma of the uterine cervix

Nina A. Mayr; Vincent A. Magnotta; James C. Ehrhardt; James A. Wheeler; Joel I. Sorosky; B.-Chen Wen; Charles S. Davis; Retta E. Pelsang; Barrie Anderson; J. Fred Doornbos; David H. Hussey; William T. C. Yuh

PURPOSE Clinical evaluation of tumor size in cervical cancer is often difficult, and clinical signs of radiation therapy failure may not be present until well after completion of treatment. The purpose of this study is to investigate early indicators of treatment response using magnetic resonance (MR) imaging for quantitative assessment of tumor volume and tumor regression rate before, during, and after radiation therapy. METHODS AND MATERIALS Thirty-four patients with cervical cancer Stages IB [5], IIB [8], IIIA [1], IIIB [14], IVA [3], IVB [1], and recurrent [2] were studied prospectively with four serial MR examinations obtained at the start of radiation therapy, at 2-2.5 weeks (20-24 Gy), at 4-5 weeks (40-50 Gy), and 1-2 months after treatment completion. Tumor volume was assessed by three-dimensional volumetric measurements using T2-weighted images of each MR examination. The volume regression rate was generated based on the four sequential MR studies. These findings were correlated with local control, metastasis rate, and disease-free survival. Median follow-up was 18 months (range: 9-43 months). RESULTS The tumor regression rate after a dose of 40-50 Gy correlated significantly with treatment outcome. The actuarial 2-year disease-free survival was 88.4% in patients with tumors regressing to < 20% of the initial volume compared with 45.4% in those with > or = 20% residual (p = 0.007). The incidence of local recurrence was 9.5% (2 out of 21) and 76.9% (10 out of 13), respectively (p < 0.001). Analysis by initial tumor volume showed that this observation was valid in patients with initial volumes between 40 and 100 cm3. Analysis by FIGO stage confirmed this observation in all patients except those with Stage IB. CONCLUSION Sequential tumor volumetry using MR imaging appears to be a sensitive measure of the responsiveness of cervical cancer to irradiation. Treatment response can be assessed as early as during the course of radiation therapy by measurement of initial tumor volume and regression rate at 40-50 Gy. In patients with large (> 40 cm3) and advanced (Stage > or = IIIA) tumors, this technique may be helpful in supplementing the clinical examination for response assessment. The identification of patients at high risk for treatment failure may ultimately lead to improved clinical outcome.


Digestive Diseases and Sciences | 1997

Effects of biofeedback therapy on anorectal function in obstructive defecation.

Satish S. Rao; Kimberly Welcher; Retta E. Pelsang

Biofeedback therapy improves symptoms inpatients with constipation and obstructive defecation.Whether it also improves anorectal function is unclear.Our purpose was to investigate prospectively the effects of biofeedback therapy on subjective andobjective parameters of anorectal function in 25consecutive patients with obstructive defecation.Biofeedback therapy consisted of pelvic floor relaxationexercises (phase I) and neuromuscular conditioning ofrectal sensation and rectoanal coordination, with asolid state manometry system and simulated defecationmaneuvers (phase II). The number of sessions wascustomized for each patient. Clinical improvement wasassessed from the changes in anorectal manometry,balloon (50 cc) expulsion test, and the symptom andstool diaries. The number of therapy sessions varied[mean (range) = 6 (2-10)]. After therapy, whenstraining as if to defecate, the percentage analrelaxation, intrarectal pressure, and defecation indexincreased (P < 0.001). The balloon expulsion time,laxative consumption, and straining effort decreased (P< 0.001). Before therapy, 16/25 (64%) patients hadimpaired rectal sensation, and after therapy thisimproved (P < 0.001). After therapy, 15/25 (60%) patients reported 75% satisfaction with bowelhabit and 8/25 (32%) reported ≥50% satisfaction (P< 0.001); 15/16 (94%) patients discontinued digitaldisimpaction. Biofeedback therapy not only improves subjective but also objective parameters ofanorectal function in at least 76% of patients byrectifying the underlying pathophysiologicdisturbance(s). Sensory conditioning and customizing thenumber of sessions may offer additionalbenefits.


International Journal of Radiation Oncology Biology Physics | 1996

Tumor size evaluated by pelvic examination compared with 3-D MR quantitative analysis in the prediction of outcome for cervical cancer

Nina A. Mayr; William T. C. Yuh; Jie Zheng; James C. Ehrhardt; Joel I. Sorosky; Vincent A. Magnotta; Retta E. Pelsang; David H. Hussey

PURPOSE Tumor size estimated by pelvic examination (PE) is an important prognostic factor in cervical cancer treated with radiation therapy (RT). Recent histologic correlation studies also showed that magnetic resonance (MR) imaging provides highly accurate measurements of the actual tumor volume. The purpose of this study was to: (a) compare the accuracy of PE and MR in predicting outcome, and (b) correlate tumor measurements by PE versus MR. METHODS AND MATERIALS Tumor measurements were performed prospectively in 43 patients with advanced cervical cancer. MR and PE were performed at the same time intervals: (a) at the start of RT, (b) after 20-24 Gy/2-2.5 weeks, (c) after 40-50 Gy/4-5 weeks, and (d) at follow-up (1-2 months after RT completion). PE measured tumor diameters in anteroposterior, lateral, and craniocaudal direction, and PE-derived tumor size was computed as maximum diameter, average diameter, and ellipsoid volume. MR-derived tumor size was calculated by summation of the tumor areas in each section and multiplication by the section thickness. Tumor regression during RT was calculated for each method as percentage of initial volume. The measurements were correlated with local failure and disease-free survival. Median follow-up was 29 months (range: 9-56 months). RESULTS Prediction of local control: Overall, tumor regression rate (rapid versus slow) was more precise than the initial tumor size in the prediction of outcome. MR provided a more accurate and earlier prediction of local control (at 2-2.5 weeks, and at 4-5 weeks of RT) than PE (only at follow-up). Based on the initial tumor size, MR was also better than PE in predicting disease-free survival and local control, particularly in large (> or = 100 cm3) tumors. Size correlation: Tumor size (maximum diameter, average diameter, volume) by PE and MR did not correlate well (r = 0.51, 0.61, and 0.58, respectively). When using MR measurements as a reference, PE tended to overestimate intermediate-size (40-99 cm3) tumors. CONCLUSION This preliminary study suggests that increased precision of tumor volume measurement leads to more accurate and earlier prediction of outcome in cervical cancer. MR tumor volumetry may be useful as an adjunct to PE in selected cases, and holds the potential to impact therapeutic decision-making.


Journal of Magnetic Resonance Imaging | 2000

Safety and efficacy of mangafodipir trisodium (MnDPDP) injection for hepatic MRI in adults: results of the U.S. multicenter phase III clinical trials (safety).

Michael P. Federle; Judith L. Chezmar; Daniel L. Rubin; Jeffrey C. Weinreb; Patrick C. Freeny; Richard C. Semelka; Jeffrey J. Brown; Joseph A. Borrello; Joseph K. T. Lee; Robert F. Mattrey; Abraham H. Dachman; Sanjay Saini; Marc J. Fenstermacher; Retta E. Pelsang; Steven E. Harms; D. G. Mitchell; Hollis H. Halford; Mark W. Anderson; C. Daniel Johnson; Isaac R. Francis; James G. Bova; Philip J. Kenney; Donald L. Klippenstein; Gregory S. Foster; David A. Turner; Arthur E. Stillman; Rendon C. Nelson; Stuart W. Young; Richard H. Patt; Matthew Rifkin

The short‐term1 safety of mangafodipir trisodium (MnDPDP) injection was studied in 546 adults with known or suspected focal liver lesions. An initial contrast‐enhanced computed tomography examination was followed by unenhanced magnetic resonance imaging (MRI), injection of MnDPDP (5 μmol/kg), and enhanced MRI. Adverse events were reported for 23% of the patients; most were mild to moderate in intensity, did not require treatment, and were not drug related. The most commonly reported adverse events were nausea (7%) and headache (4%). The incidence of serious adverse events was low (nine events in six patients) and not drug related. Injection‐associated discomfort was reported for 69% of the patients, and the most commonly reported discomforts included heat (49%) and flushing (33%). Changes in laboratory values and vital signs were generally transient, were not clinically significant, and did not require treatment. There were no clinically significant short‐term risks from exposure to MnDPDP. J. Magn. Reson. Imaging 2000;12:186–197.


The American Journal of Gastroenterology | 2002

Phantom study to determine radiation exposure to medical personnel involved in ERCP fluoroscopy and its reduction through equipment and behavior modifications

Frederick C. Johlin; Retta E. Pelsang; Mary Greenleaf

OBJECTIVE:The aim of this work is to evaluate the potential radiation exposure to medical personnel by comparing results from phantom studies of two different fluoroscopic units used for ERCP, and to determine which equipment or behavior modification can reduce radiation exposure.METHODS:Radiation exposures using an opaque tissue equivalent chest phantom with an abdominal insert were performed on a stationary dedicated fluoroscopy unit and a mobile C-arm unit, comparing varying equipment manipulations. Scatter radiation was recorded at 1) the patients’ head, 2) where the endoscopist stands, and 3) where the equipment personnel stands.RESULTS:Radiation exposures were significantly higher for the mobile C-arm unit, revealing a 4160-times greater dosage increase for head and neck and a 8660-times increase for body than the fixed unit. Tower position and vertically stationed lead shields facilitated exposure reduction by means of equipment manipulation. The positioning of the endoscopist away from the right corner of the units also decreased exposure.CONCLUSIONS:Dedicated stationary fluoroscopy units provide significantly less radiation exposure. Equipment and behavior modification including tower positioning down and vertical shielding are essential for reduction in radiation exposure to medical personnel.


The American Journal of Gastroenterology | 2001

Management of suppurative pylephlebitis by percutaneous drainage: placing a drainage catheter into the portal vein

Retta E. Pelsang; Frederick C. Johlin; Rommel Dhadha; Marta M. Bogdanowicz; Gary D. Schweiger

Persistent infection of the portal vein is a rare entity with significant mortality. We present two cases of infected thombis of the portal vein, one infected with fungus and the other with bacteria, both requiring percutaneous drainage to allow a response to antibiotics. The distinction between bland thrombis, infected thrombis, portal venous air, and pneumobilia will be discussed so that suppurative pylephlebitis can be recognized more easily as drain placement appears to affect a more prompt degree of improvement than antibiotics alone.


Journal of Ultrasound in Medicine | 1996

Pulsatile lower limb venous Doppler flow: prevalence and value in cardiac disease diagnosis.

M E Kakish; Monzer M. Abu-Yousef; P B Brown; Niall G. Warnock; Thomas J. Barloon; Retta E. Pelsang

The purpose of this study was to assess the frequency and significance of pulsatile Doppler waveforms in lower limb veins. We used Doppler sonographic data from the common femoral vein. In the first of two groups, the findings in 250 patients were correlated with the presence of cardiac decompensation on concurrent chest radiographs. In the second group, the findings in 81 patients were correlated with the presence of tricuspid regurgitation on Doppler echocardiograms. A venous Doppler sonographic examination was considered normal if spontaneous anterograde phasic flow was present and pulsatile if flow had a cyclic retrograde component. In group 1, 21% had pulsatile waveforms whereas 24% had cardiac decompensation. In group 2, 36% had pulsatile waveforms and 43% had tricuspid regurgitation. A statistically significant correlation was found between the presence of these abnormal waveforms and cardiac decompensation or tricuspid regurgitation, with sensitivities of 57% and 54%, specificities of 91% and 78%, positive predictive values of 66% and 66%, negative predictive values of 87% and 69%, and accuracies of 82% and 68%, respectively. In a subgroup of 55 patients who had both tests for correlation and in whom both were in agreement, the sensitivity of venous Doppler sonographic examination for detecting pathologic cardiac conditions was 79%, specificity was 87%, positive predictive value was 83%, negative predictive value was 84%, and accuracy was 84%. In 77 patients with pulsatile waveforms, including 24 without concurrent chest radiographs or echocardiograms, 63 (82%) had no prior history of cardiac disease. When correlated separately with chest radiograph or Doppler echocardiography, the test is not very sensitive in the diagnosis of cardiac disease; however, when both correlating tests are performed and are in agreement, all diagnostic parameters of the venous Doppler sonographic test, including sensitivity, become fairly high. The presence of pulsatile lower limb venous Doppler flow should alert the sonologist that a pathologic cardiac condition may be the culprit, especially in patients who have no such prior diagnosis.


Journal of Ultrasound in Medicine | 1994

Diagnosis of acute appendicitis on transvaginal ultrasonography.

Retta E. Pelsang; Niall G. Warnock; Monzer M. Abu-Yousef

Appendicitis is the most common acute abdominal condition requiring surgery in the western world.1 The combination of signs, symptoms, and laboratory values may, however, be equivocal in approximately one-third of patients with acute appendicitis.1 Diagnosis is particularly difficult in young women of childbearing age in whom acute gynecologic problems can be confused with acute appendicitis. In such patients, an increased rate of normal appendices are found more frequently at surgery (35 to 40%).2.3 Using transabdominal ultrasonography in patients with clinical suspicion of appendicitis, an accurate diagnosis of appendicitis can be made in approximately 52% of young women, and an alternative diagnosis can be made in 33%.4 Many advocate graded compression sonography of the right lower quadrant to evaluate for appendicitis, combined with transvaginal ultrasonography of the pelvis for evaluation of acute gynecologic pathologic processes. We endorse this view but present the two cases in whom the diagnosis of acute appendicitis was made at the transvaginal examination.


Abdominal Imaging | 1997

A percutaneous biopsy technique for patients with suspected biliary or pancreatic cancer without a radiographic mass

Retta E. Pelsang; F. C. Johlin

Abstract.Background: Treatment of malignant pancreatic and/or biliary strictures requires tissue diagnosis. Since cytologic brushings at endoscopic retrograde cholangiopancreatography (ERCP) of these strictures has a poor sensitivity for malignancy (30–83%) (see ME Ryan. Gastrointestinal Endoscopy 1991;37(2):139–143; and MB Cohen, Wittchow RJ, Johlin FC, et al. Mod Pathol 1995;8:498–502), tissue diagnosis must be obtained by another route. We report our experience of percutaneous biopsy of malignant pancreatic and/or biliary strictures even when no radiographic mass is present. Methods: At ERCP, five patients demonstrated pancreatic and/or biliary duct strictures, had atypical cytological brushings, and had their strictures stented. No mass to account for the strictures could be identified on CT. These five patients underwent percutaneous biopsy of the peri-stent material by CT within 10 days of the ERCP. Results: Two patients had adenocarcinoma of the pancreas. One patient had malignant lymphoma and another had cholangiocarcinoma. One patient had inflammatory cells and was followed. Conclusions: If the diagnosis of malignancy cannot be made at the time of the ERCP sampling, then our experience suggests that a percutaneous biopsy should be performed even if a mass is not present using the stent as a target.

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