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1.
Surg Laparosc Endosc Percutan Tech ; 29(1): 22-25, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30520816

ABSTRACT

Radiation exposure during endoscopic retrograde cholangiopancreatography is known, however, data in relation to radiation usage is unclear. We evaluate radiation exposure using fluoroscopy dose (FD) and time (FT). A prospective analysis of 197 patients undergoing endoscopic retrograde cholangiopancreatography was completed. Univariate and multivariate analyses were performed to determine characteristics associated with higher FD and FT. The mean FT was 307 seconds; the mean FD was 16.5 centigray. On univariate and multivariate analysis, indication of common bile duct stricture and pancreatic stricture, interventions including dilation and the use of plastic stents placement, procedures that were moderately or very difficult, and procedures that used magnification and high-resolution images were associated with higher FD± and longer FT. Indications of common bile duct stricture and pancreatic stricture as well as interventions of dilation, plastic stents placement, and procedures that are moderately or very difficult, involve high-resolution image leading to a higher radiation exposure. Special care should be considered in these settings.


Subject(s)
Cholangiopancreatography, Endoscopic Retrograde/adverse effects , Cholestasis/surgery , Fluoroscopy/adverse effects , Pancreatic Diseases/surgery , Pancreatic Ducts/surgery , Cholangiopancreatography, Endoscopic Retrograde/methods , Constriction, Pathologic/surgery , Female , Fluoroscopy/statistics & numerical data , Humans , Male , Middle Aged , Prospective Studies , Radiation Dosage , Time Factors
2.
Am J Gastroenterol ; 112(5): 716-721, 2017 05.
Article in English | MEDLINE | ID: mdl-27958287

ABSTRACT

OBJECTIVES: Current international guidelines for ocular radiation exposure suggest a threshold of 20 millisieverts (mSv)/year. Although endoscopists wear lead aprons, use of protective eye wear is optional. This study was conducted to analyze the lens radiation exposure during endoscopic retrograde cholangiopancreatography (ERCP) for endoscopists to determine the time of fluoroscopy needed to warrant using lens protection during ERCP. METHODS: ERCP patients were prospectively enrolled. Indications, interventions, fluoroscopy time, dose, and attending ± fellow involvement were recorded. Radiation exposure was collected from body dosimeters and dosimeters placed between the eyes. Cumulative radiation doses were obtained at study completion and averaged over the total fluoroscopy time to determine the mSv/hour exposure. RESULTS: A total of 187 cases were included. Attendings and fellows wore lens dosimeters in 178 and 126 cases, respectively, and body dosimeters in 174 and 128 cases, respectively. Attendings and fellows wore lens dosimeters throughout 15.89 and 11.24 h of fluoroscopy, respectively. The cumulative radiation dose absorbed per lens dosimeters was 5.35 mSv for attendings and 2.55 mSv for fellows. The projected lens absorption by the body dosimeters was 19.03 mSv for attendings and 5.21 mSv for fellows. The hourly fluoroscopy lens exposure was 0.34 mSv/hour for attendings and 0.23 mSv/hour for fellows. CONCLUSIONS: The amount of fluoroscopy hours needed to reach the currently suggested lens threshold limit (20 mSv/year) was 59.41 h for attendings and 88.17 h for fellows. Radioprotective eye wear should be worn by physicians with yearly fluoroscopy times in similarly structured practices that meet or exceed these thresholds.


Subject(s)
Cholangiopancreatography, Endoscopic Retrograde , Fluoroscopy , Gastroenterology , Lens, Crystalline , Occupational Exposure , Radiation Dosage , Aged , Eye Protective Devices , Fellowships and Scholarships , Female , Humans , Male , Middle Aged , Occupational Exposure/prevention & control , Prospective Studies , Radiation Monitoring , Threshold Limit Values , Time Factors
4.
Radiographics ; 29(4): 1179-89, 2009.
Article in English | MEDLINE | ID: mdl-19605664

ABSTRACT

Image artifacts are commonly encountered in clinical ultrasonography (US) and may be a source of confusion for the interpreting physician. Some artifacts may be avoidable and arise secondary to improper scanning technique. Other artifacts are generated by the physical limitations of the modality. US artifacts can be understood with a basic appreciation of the physical properties of the ultrasound beam, the propagation of sound in matter, and the assumptions of image processing. US artifacts arise secondary to errors inherent to the ultrasound beam characteristics, the presence of multiple echo paths, velocity errors, and attenuation errors. The beam width, side lobe, reverberation, comet tail, ring-down, mirror image, speed displacement, refraction, attenuation, shadowing, and increased through-transmission artifacts are encountered routinely in clinical practice. Recognition of these artifacts is important because they may be clues to tissue composition and aid in diagnosis. The ability to recognize and remedy potentially correctable US artifacts is important for image quality improvement and optimal patient care.


Subject(s)
Artifacts , Image Enhancement/methods , Ultrasonography/methods
5.
Neurosurgery ; 51(2): 343-55; discussion 355-7, 2002 Aug.
Article in English | MEDLINE | ID: mdl-12182772

ABSTRACT

OBJECTIVE: The objective of the Brain Tumor Cooperative Group NIH Trial 87-01 trial was to investigate the effect of additional implanted radiation therapy in newly diagnosed patients with pathologically confirmed malignant gliomas. METHODS: The study involved a randomized comparison of surgery, external beam radiotherapy, and carmustine (BCNU) versus surgery, external beam therapy, interstitial radiotherapy boost, and BCNU in newly diagnosed malignant gliomas. (125)I was chosen as best suited for this effort because it allowed preimplantation planning and postimplantation quality assurance review. Two hundred ninety-nine patients met the eligibility criteria and were randomized into the two arms of the study between December 1987 and April 1994. Follow-up continued for an additional 3 years. Twenty-nine patients were identified as having committed protocol violations and were excluded, resulting in 270 subjects in the Valid Study Group. One hundred thirty-seven patients received external beam radiation and BCNU, and 133 underwent the (125)I implantation plus external beam radiation and BCNU therapy. RESULTS: The overall median survival for the Valid Study Group was 64.3 weeks. The median survival for patients receiving additional therapy of (125)I was 68.1 weeks, and median survival for those receiving only external beam radiation and BCNU was 58.8 weeks. The cumulative proportion surviving between the two treatment groups was not statistically significantly different (log-rank test, P = 0.101). As in other studies in the literature, age, Karnofsky score, and pathology were predictors of mortality. Additional analyses incorporating an adjustment for these prognostic variables, either in a stratified analysis or Cox proportional hazards model, did not result in statistically significant differences in the cumulative proportion of patients surviving between the two treatment groups. CONCLUSION: We conclude that there is no long-term survival advantage of increased radiation dose with (125)I seeds in newly diagnosed glioma patients.


Subject(s)
Antineoplastic Agents, Alkylating/therapeutic use , Brain Neoplasms/therapy , Carmustine/therapeutic use , Glioma/therapy , Neurosurgical Procedures , Radiotherapy/methods , Brachytherapy , Combined Modality Therapy , Dose-Response Relationship, Radiation , Female , Humans , Male , Middle Aged , Pilot Projects , Quality Assurance, Health Care , Survival Analysis
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