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At least 1,495 records · Page 83Linked to original sources

Percutaneous radiologic gastrostomy with and without T-fastener gastropexy: a randomized comparison study.

PURPOSE: T-fastener gastropexy is used by many interventional radiologists during percutaneous radiologic gastrostomy (PRG) placement. Whether gastropexy is a prerequisite to safe gastrostomy placement is uncertain. We evaluated the use of T-fastener gastropexy versus no gastropexy for PRG in a prospective, randomized study. METHODS: Of 90 consecutive patients referred for PRG, 48 were randomly selected to receive T-fastener gastropexy (M:F, 35:13; mean age 62 years, range 20-90 years) and 42 to receive no gastropexy (M:F, 31:11; mean age 63 years, range 40-90 years). Technical difficulties and fluoroscopy times were recorded for both groups and all patients were followed up for postprocedural complications. T-fasteners were removed between 3 and 7 days after gastrostomy insertion. RESULTS: A major complication was encountered in four patients from the non-gastropexy group (10%). In these cases the guidewire and dilator "flipped" out of the stomach into the peritoneal cavity. This resulted in misplacement of the gastrostomy tube in the peritoneal cavity in two of the patients. This was discovered at the end of the procedure when a test injection of contrast medium was performed. In three of these patients the procedure was rescued and completed radiologically. One patient underwent endoscopic gastrostomy placement. Five of 48 patients (10%) who received a gastropexy had pain associated with the T-fastener sites. Six patients (13%) had skin excoriation at the T-fastener sites. No skin complications were seen in the non-gastropexy group. No statistical difference in fluoroscopy time was observed between the two groups. CONCLUSION: Our experience of PRG without T-fastener gastropexy involved a 10% incidence of serious technical complications. We suggest that T-fastener gastropexy should be performed routinely for all PRG procedures. T-fastener gastropexy has an associated minor complication of pain and skin excoriation at the gastrostomy site which resolves on removing the T-fasteners.

Abdominal Wall↗

Angiographic guidewire with measuring markers: design and clinical experience.

PURPOSE: We have developed an angiographic guidewire with measuring markers to determine accurately how far a guidewire is inserted within a catheter. We investigated whether use of this guidewire reduces the risk of vascular injury and the fluoroscopic time during guidewire manipulations. METHODS: Four markers were put on the surface of the guidewire at 80, 100, 110, and 120 cm from the tip. The actual lengths of 54 catheters from seven manufacturers were measured and compared with the nominal lengths. Sixty consecutive patients who underwent angiography were randomized into two groups: in one group guidewires with surface markers were used (marker group) and in the other group, conventional guidewires (control group). For each guidewire insertion, the fluoroscopic time before the guidewire was pushed forward into the vessel lumen was recorded. The number of occasions on which unintentionally the guidewire had already been pushed out of the catheter at the start of fluoroscopy was also evaluated. RESULTS: The actual lengths of all catheters were greater than the nominal lengths by 1.0-11.0 cm. Mean fluoroscopic time for each guidewire insertion was 3.3 sec in the marker group and 5.7 sec in the control group (p < 0.05). Guidewires were unintentionally pushed out of the catheters without fluoroscopy three times (3.6%), in each case in the control group. CONCLUSION: The guidewire with measuring markers is effective for enhancing safety and in reducing fluoroscopic radiation during angiographic procedures. It is recommended that operators be aware that actual lengths of catheters may vary significantly from the nominal lengths listed; they should be aware of this with any guidewire, but particularly with the angiographic measuring guidewire.

Aged↗

Peripheral insertion of a central venous access device under fluoroscopic guidance using a peripherally accessed system (PAS) port in the forearm.

PURPOSE: We describe the technique, efficacy, and complications of fluoroscopy-guided implantation of a central venous access device using a peripherally accessed system (PAS) port via the forearm. METHODS: Beginning in July 1994, 105 central venous access devices were implanted in 104 patients for the long-term infusion of antibiotics or antineoplasmic agents, blood products, or parenteral nutrition. The devices was inserted under fluoroscopic guidance with real-time venography from a peripheral route. RESULTS: All ports were successfully implanted. There were no procedure-related complications. No thrombosis or local infection was observed; however, in six patients catheter-related phlebitis occurred. CONCLUSION: Fluoroscopy-guided implantation of a central venous access device using a PAS port via the forearm is safe and efficacious, and injection of contrast medium through a peripheral IV catheter before introduction of the catheter helps to avoid catheter-related phlebitis.

Adolescent↗

Routine chest radiographs after central line insertion: mandatory postprocedural evaluation or unnecessary waste of resources?

PURPOSE: To study the cost and impact on patient management of the routine performance of chest radiographs in patients undergoing imaged-guided central venous catheter insertion. METHODS: Six hundred and twenty-one catheters placed in 489 patients over a 42-month period formed the study group. Catheters were placed in the right internal jugular vein (425), left internal jugular vein (133), and subclavian veins (63). At the end of the procedure fluoroscopy was used to assess catheter position and check for complications. A postprocedural chest radiograph was obtained in all patients. RESULTS: Postprocedural chest fluoroscopy showed no evidence of pneumothorax, hemothorax, or mediastinal hematoma. Inappropriate catheter tip position or catheter kinks were noted with 90 catheters. These problems were all corrected while the patient was on the interventional table. Postprocedural chest radiographs showed no complications but proximal catheter tip migration was noted in six of 621 catheters (1%). These latter six catheters required further manipulation. The total technical and related charges for the postprocedural chest radiographs in this series were estimated at pound15,525. CONCLUSION: Postprocedural chest radiographs after image-guided central venous catheter insertion are not routinely required. A postprocedural chest radiograph can be performed on a case-by-case basis at the discretion of the interventional radiologist.

Adolescent↗

Radiation dose optimization in coronary angiography and percutaneous coronary intervention (PCI). I. Experimental studies.

The objectives of this study were to evaluate the influence on image quality and dose to the patient and operator of various equipment settings for percutaneous coronary intervention (PCI), and to optimize the set-up. With an Alderson phantom, different settings, such as projection, protective screens, filtration, image intensifier size and collimation, were evaluated. Kerma-area product (KAP) was recorded as a measure of patient dose and scattered radiation was measured with an ionization chamber. Effective dose for a standardized PCI procedure was measured with thermoluminescent dosimeters inside the phantom. Image quality was evaluated with a contrast-detail phantom. Based on these findings, the equipment set-up was optimized to a low fluoroscopy dose rate with a sufficient image quality. Several operating parameters affected dose, particularly scattered radiation. The optimization reduced the fluoroscopy KAP rate from 44 to 16 mGy cm(2)/s using 15 cm of acrylic. The effective dose was reduced from 13 to 4.6 mSv for a standardized PCI procedure. Radiation dose to patient and operator in PCI is heavily dependent on both equipment set-up and operating parameters which can be influenced by the operator. With a careful optimization, a large reduction of radiation dose is possible.

Angioplasty, Balloon, Coronary↗

Radiogenic risks from hysterosalpingography.

The aim of this study was to determine ovarian dose, effective dose and associated radiogenic risks from hysterosalpingography (HSG), and to provide data for the estimation of radiogenic risks related to HSG studies performed in any laboratory. The fluoroscopy time, number of radiographs taken and entrance surface dose were measured in a series of 78 consecutive patients undergoing HSG as part of their infertility work-up. Organ-dose values per radiograph and per minute of fluoroscopy were separately determined using an anthropomorphic phantom and thermoluminescence dosimetry. The radiogenic risk for deleterious effects on a possible future embryo and the radiogenic risk for cancer induction on the patient undergoing HSG were estimated. The average HSG procedure in our laboratory involves a mean fluoroscopic time of 0.3 min and a mean number of radiographs of 3.2. The dose to female gonads from an average HSG procedure was 2.7 mGy and the patient effective dose was 1.2 mSv. The risk for radiogenic anomalies in a future embryo of the woman undergoing an average HSG procedure and the risk for radiogenic fatal cancer induction in the exposed woman were estimated to be less than 10(-3) of the correspondent nominal risks. Radiation risks from a typical HSG are low, but they may be elevated if fluoroscopic and/or radiographic exposures are prolonged for any reason. Present data allow the estimation of radiogenic risks associated with HSG procedures performed in other laboratories with use of different equipment, screening time and number of radiographs taken.

Abnormalities, Radiation-Induced↗

Dose and image quality in the comparison of analogue and digital techniques in paediatric urology examinations.

In paediatric radiology it has been recognised that children have a higher risk of developing cancer from the irradiation than adults (two to three times); therefore, increased attention has been directed towards the dose to the patient. In this study the effect on patient dose and image quality in replacing the exposure in micturating cystourethrography (MCUG) examinations with the stored fluoroscopy image has been investigated. In the intravenous urography (IVU) examination we compared analogue and digital image quality, but the dose measurements were performed on a phantom. Standard clinical X-ray equipment was used. Sixty-eight patients in each of two centres were studied for the MCUG. Doses were measured with a dose-area product (DAP) meter and the image quality was scored. A non-parametric statistical analysis was performed. For the IVU, a phantom was used in the dose measurements but clinical images were scored in the comparison between analogue and digital images. For the MCUG, replacing the exposure with stored fluoroscopy images lowered the DAP value from 0.77 to 0.50 Gy cm2. The image quality did not show any difference between the techniques; however, if reflux was to be graded, exposure was needed. For the IVU, the doses could be lowered by a factor of 3 using digital techniques. The image quality showed no statistical difference between the two techniques. There is a potential for a substantial dose reduction in both MUCG and IVU examinations using digital techniques.

Child↗

Dose reduction in evacuation proctography.

The goal of this study was to reduce the patient radiation dose from evacuation proctography. Ninety-eight consecutive adult patients referred for proctography to investigate difficult rectal evacuation were studied using a digital imaging system with either a standard digital program for barium examinations, a reduced dose digital program (both with and without additional copper filtration), or Video fluoroscopy. Dose-area products were recorded for each examination and the groups were compared. All four protocols produced technically acceptable examinations. The low-dose program with copper filtration (median dose 382 cGy cm2) and Video fluoroscopy (median dose 705 cGy cm2) were associated with significantly less dose than other groups (p < 0.0001). Patient dose during evacuation proctography can be reduced significantly without compromising the diagnostic quality of the examination. A digital program with added copper filtration conveyed the lowest dose.

Adult↗

Cement leakage during vertebroplasty: an underestimated problem?

Overall, vertebroplasty has a low complication rate. Nevertheless, severe complications can occur. The majority of these are related to cement extrusion. The rate of cement leakage is often obtained by X-ray, with only a single leak registration per vertebra. Detection rate of leaks in comparison with CT and inter-observer reliability for X-ray is, in large parts, unknown. We conducted this study to determine the value of fluoroscopy and X-ray used to detect cement leakage as compared to CT scans. Intraoperative findings in lateral fluoroscopy by the surgeon, and postoperative findings in X-rays by two orthopaedic surgeons, were compared with CT scans for the same study group. Multiple cement leakage was considered, and agreement rate was determined. The detection rate for leaks was 34% for lateral X-ray and 48% for lateral and AP view. Additional AP views only enhanced the detection of leaks in the segmental veins. The agreement rate between fluoroscopy/X-ray and CT scans ranged between 66% and 74%, while inter-observer reliability showed only fair agreement. The rate of cement leaks in vertebroplasty is high if multiple leaks are considered in CT scans. Detection rates using X-rays are low and complicated by only fair inter-observer agreement. Leaks in the basivertebral veins are frequently misinterpreted and can lead to severe complications. Therefore, CT scans should be obtained to calculate the exact leakage rate and to assess persistent or new pain occurring postoperatively.

Aged↗

Prospective randomized comparison of radiation exposure from full spine radiographs obtained in three different techniques.

PROBLEM: The purpose of the investigation was a comparison of two different digital X-ray techniques with conventional standing full spine films. Evaluation of dose area product, image quality and inter-observer error of Cobb-angle measurement in patients with scoliosis and kyphoscoliosis were studied. METHODS: A consecutive series of 150 patients were prospectively randomized into three groups. Patients in group 1 (n=53) received a conventional standing postero-anterior full spine radiograph. All films were evaluated on the light box. Patients in group 2 (n=48) received a X-ray using the digital storage phosphor plate system (CR). For group 3 (n=49) digital pulsed fluoroscopy was used. In groups 2 and 3 images were exported to a picture archiving and communicating system (PACS) workstation and viewed on a monitor (Siemens SMM 21140P, Germany). Dose area product measurements were performed in all three groups (Diamentor-M, PTW, Freiburg). Three experienced investigators independently reviewed all pictures. Pedicles and endplates were counted. Cobb-angles of the main curves were measured. RESULTS: The mean dose area product was 97.0 cGy cm(2) (37.0-380.0 cGy cm(2)) for conventional films, 31.5 cGy cm(2) (6.0-66.0 cGy cm(2)) for CR imaging and 5.0 cGy cm(2) (1.0-29.0 cGy cm(2)) for digital fluoroscopy. The differences of Cobb-angle measurements were not significantly different for the three methods. Differences in the count of pedicles and endplates between the investigators were significantly lower for the conventional film as an indicator for the best detail presentation. CONCLUSION: A significant reduction in dose area product is possible with modern digital X-ray methods. The inter-observer error of Cobb-angle measurement is not significantly altered. The detail information is decreased in comparison to conventional films.

Adolescent↗

Cervical pedicle screw placement: feasibility and accuracy of two new insertion techniques based on morphometric data.

This morphometric and experimental study was designed to assess the dimensions and axes of the subaxial cervical pedicles and to compare the accuracy of two different techniques for subaxial cervical pedicle screw (CPS) placement using newly designed aiming devices. Transpedicular fixation is increasingly used for stabilizing the subaxial cervical spine. Development of the demanding technique is based on morphometric studies of the pedicle anatomy. Several surgical techniques have been developed and evaluated with respect to their feasibility and accuracy. The study was carried out on six conserved human cadavers (average age 85 years). Axes and dimensions of the pedicles C3-C7 (60 pedicles) were measured using multislice computed tomography (CT) images prior to surgery. Two groups consisting of 3 specimens and 30 pedicles each were established according to the screw placement technique. For surgical technique 1 (ST1) a para-articular mini-laminotomy was performed. Guidance of the drill through the pedicle with a handheld aiming device attached onto the medial aspect of the pedicle inside the spinal canal. Screw hole preparation monitored by lateral fluoroscopy. In surgical technique 2 (ST2) a more complex aiming device was used for screw holes drilling. It consists of a frame with a fully adjustable radiolucent arm for carrying the instruments necessary for placing the screws. The arm was angled according to the cervical pedicle axis as determined by the preoperative CT scans. Drilling was monitored by lateral fluoroscopy. In either technique 3.5 mm screws made of carbon fiber polyetheretherketone (CF-PEEK) were inserted. The use of the CF-PEEK screws allowed for precise postoperative CT-assessment since this material does not cause artifacts. Screw placement was qualified from ideal to unacceptable into four grades: I = screw centered in pedicle; IIa = perforation of pedicle wall less than one-fourth of the screw diameter; IIb = perforation more than one-fourth of the screw diameter without contact to neurovascular structures; III = screw more than one-fourth outside the pedicle with contact to neurovascular structures. Fifty-six pedicle screws could be evaluated according to the same CT protocol that was used preoperatively. Accuracy of pedicle screw placement did not reveal significant differences between techniques 1 and 2. A tendency towards less severe misplacements (grade III) was seen in ST2 (15% in ST2 vs. 23% in ST1) as well as a higher rate of screw positions graded IIa (62% in ST2 vs. 43% in ST1). C4 and C5 were identified to be the most critical vertebral levels with three malpositioned screws each. Because of the variability of cervical pedicles preoperative CT evaluation with multiplanar reconstructions of the pedicle anatomy is essential for transpedicular screw placement in the cervical spine. Cadaver studies remain mandatory to develop safer and technically less demanding procedures. A similar study is projected to further develop the technique of CPS fixation with regard to safety and clinical practicability.

Aged, 80 and over↗

Robot-assisted versus freehand cannulated-screw fixation for femoral neck fractures: a systematic review of technical, clinical and adoption outcomes.

Robot-assisted guidance may improve the technical precision of percutaneous cannulated-screw fixation for femoral neck fractures. Whether these procedural advantages translate into better clinical outcomes remains uncertain. We compared robot-assisted and conventional freehand fixation in adults with femoral neck fractures. MEDLINE, Embase and CINAHL were searched from inception to 15 July 2026 without language restrictions. Google Scholar was used only as a supplementary search source, together with forward and backward citation searching. Comparative studies of robot-assisted versus freehand fluoroscopy-guided cannulated-screw fixation were included. Risk of bias was assessed using RoB 2 and ROBINS-I, with the Newcastle-Ottawa Scale used as a complementary appraisal of non-randomised studies. Random-effects meta-analyses included prediction intervals and prespecified sensitivity analyses. The protocol was registered prospectively (PROSPERO CRD420261465038). Sixteen comparative studies involving 1,293 participants were included. Of these, 597 underwent robot-assisted fixation and 696 underwent freehand fixation. Two studies reporting random allocation and 14 non-randomised studies were included in the study. Robot-assisted fixation was associated with fewer guide-wire manipulations, greater screw-placement accuracy and 13.9 fewer fluoroscopic acquisitions per procedure (95% confidence interval [CI] -20.3 to -7.5). Earlier radiographic healing and modestly higher final Harris Hip Scores were also observed. Pooled estimates suggested lower risks of union failure, avascular necrosis and composite complications. Fluoroscopy duration, overall operative time and reoperation did not differ significantly. Heterogeneity was substantial for several continuous outcomes, with prediction intervals crossing the null for several estimates, indicating that the magnitude of benefit varied considerably between studies. Some clinical associations were also sensitive to eligibility-restricted analyses. Robot-assisted cannulated-screw fixation improves technical execution compared with freehand fixation. Patient-important clinical superiority and economic value have not been established, and evidence concerning learning curves, operator acceptability and system reliability remains insufficient. Current evidence does not support routine widespread adoption; adequately powered multicentre randomised trials incorporating economic and implementation evaluation are required.

Humans↗

Noninvasive diagnosis of ischemic cardiomyopathy by fluoroscopic detection of coronary artery calcification.

Twenty-four patients with severe congestive heart failure and cardiomegaly in whom the presence or absence of significant coronary disease could not be ascertained clinically underwent fluoroscopy for coronary artery calcification prior to cardiac catheterization. Ten of the patients were found to have significant coronary artery disease, and 14 had normal coronary arteriograms. Coronary artery calcification was found in all ten patients with significant coronary disease, and was absent in all of those patients with normal coronary arteriograms. We conclude that fluoroscopy for coronary artery calcification provides a reliable noninvasive method for differentiating ischemic from nonischemic cardiomyopathy.

Adult↗

Prevalence of fluoroscopic coronary calcific deposits in high-risk asymptomatic persons.

Coronary calcific deposits are always associated with coronary atherosclerosis. Sensitive radiographic technology can detect coronary calcium before atherosclerosis becomes symptomatic. A total of 1461 asymptomatic high-risk adult subjects were studied with digital subtraction fluoroscopy to detect coronary calcium. Risk factor data were recorded including age, sex, family history, smoking history, diabetes history, body mass index, systolic blood pressure, left ventricular hypertrophy on ECG, total serum cholesterol level, high-density lipoprotein (HDL) cholesterol, and total cholesterol/HDL ratio. Digital subtraction fluoroscopy in the left anterior oblique projection was performed in all subjects. The prevalence of calcific deposits in at least one major coronary artery was high (58.3%). Eleven percent had coronary calcium in all three major arteries. Multivariate logistic regression analysis showed significant correlations (p < 0.05) between the prevalence of coronary calcium and age, smoking history (relative risk = 1.30), diabetes history (relative risk = 1.24), and family history (relative risk = 1.26). In older subjects (at least 65 years of age), smoking and serum lipoproteins assumed greater importance as contributors to coronary calcium, whereas in younger subjects a history of diabetes was more significant. Coronary calcific deposits are prevalent in high-risk asymptomatic subjects. Their occurrence is closely related to most known risk factors.

Age Distribution↗

Comparative accuracy of clinical tests for diagnosis and prognosis of coronary artery disease.

The discriminant accuracy of 14 variables derived from clinical evaluation, cardiac fluoroscopy, exercise electrocardiography, thallium scintigraphy and radionuclide angiography was assessed with respect to the diagnosis of angiographic coronary artery disease (CAD) among 607 patients undergoing coronary angiography, and with respect to the prognosis of subsequent cardiac death or nonfatal infarction among 4,104 patients followed for 1 year after testing. Discriminant accuracy (quantified in terms of the area under a receiver-operating characteristic curve for each variable) ranged from 50 to 73% for diagnosis, and from 54 to 77% for prognosis. Although there was a great deal of variability from test to test, variables representing direct or indirect manifestations of myocardial ischemia tended to correlate better with prognosis. Thus, variables derived from radionuclide angiography and thallium scintigraphy tended to have more prognostic accuracy than diagnostic accuracy, while fluoroscopy tended to have more diagnostic accuracy than prognostic accuracy. The pattern associated with clinical evaluation and exercise electrocardiography was less discernable. Accordingly, the accuracy of noninvasive tests with respect to diagnosis and prognosis of CAD should be separately determined based on individual empiric observation.

Adult↗

Radiation exposure to patients and medical personnel during radiofrequency catheter ablation for supraventricular tachycardia.

Radiofrequency catheter ablation is an effective alternative to medical therapy for patients with supraventricular arrhythmias. The purpose of this study was to determine the risks to the patient and to medical personnel due to radiation exposure from fluoroscopy during radiofrequency ablation of supraventricular tachycardia. One hundred eight consecutive patients with Wolff-Parkinson-White syndrome or atrioventricular nodal reentry who underwent the ablation procedure were studied. The ablation procedure was successful in 95% of the patients studied. Preexcitation or supraventricular tachycardia recurred in 5% of the patients during a mean follow-up of 9 +/- 4 months. The mean fluoroscopy time was 50 +/- 31 minutes. An anthropomorphic radiologic phantom was used to determine organ exposure and the effective dose equivalents for the patient and medical personnel. The patient's effective dose equivalent during a representative ablation procedure was 1.7 rems, which is comparable to other invasive cardiovascular procedures. The risk of inducing a fatal cancer from this exposure is 1 chance in 745, which is 1% of the spontaneous risk. The risk of a serious birth defect is 1 chance in 80,000, which is 0.1% of the current incidence of serious birth defects in the United States. The cardiologist who receives the highest exposure among medical personnel, would incur 1.8 mrems per case or 450 mrems per year if 250 procedures were performed. This exposure is 9% of the recommended annual limit. These results demonstrate the efficacy of radiofrequency energy ablation of supraventricular tachycardia and confirm that radiation exposure to patients and medical personnel is within established guidelines.

Electrocoagulation↗

Quantification of coronary artery calcium using ultrafast computed tomography.

Ultrafast computed tomography was used to detect and quantify coronary artery calcium levels in 584 subjects (mean age 48 +/- 10 years) with (n = 109) and without (n = 475) clinical coronary artery disease. Fifty patients who underwent fluoroscopy and ultrafast computed tomography were also evaluated. Twenty contiguous 3 mm slices were obtained of the proximal coronary arteries. Total calcium scores were calculated based on the number, areas and peak Hounsfield computed tomographic numbers of the calcific lesions detected. In 88 subjects scored by two readers independently, interobserver agreement was excellent with identical total scores obtained in 70. Ultrafast computed tomography was more sensitive than fluoroscopy, detecting coronary calcium in 90% versus 52% of patients. There were significant differences (p less than 0.0001) in mean total calcium scores for those with versus those without clinical coronary artery disease by decade: 5 versus 132, age 30 to 39 years; 27 versus 291, age 40 to 49 years; 83 versus 462, age 50 to 59 years; and 187 versus 786, age 60 to 69 years. Sensitivity, specificity and predictive values for clinical coronary artery disease were calculated for several total calcium scores in each decade. For age groups 40 to 49 and 50 to 59 years, a total score of 50 resulted in a sensitivity of 71% and 74% and a specificity of 91% and 70%, respectively. For age group 60 to 69 years, a total score of 300 gave a sensitivity of 74% and a specificity of 81%. The negative predictive value of a 0 score was 98%, 94% and 100% for age groups 40 to 49, 50 to 59 and 60 to 69 years, respectively. Ultrafast computed tomography is an excellent tool for detecting and quantifying coronary artery calcium.

Adult↗

The tangential breast match plane: practical problems and solutions.

The three-field breast set-up, in which tangential oblique opposed fields are joined to an anterior supraclavicular field, has been the method of choice for treatment of breast cancer for many years. In the last several years many authors have suggested refinements to the technique that improve the accuracy with which fields join at a match plane. The three-field breast set-up, using a rotatable half-beam block is the technique used at our institution. In instituting this procedure, several practical problems were encountered. Due to the small collimator rotation angles used it is possible to clinically reverse the collimator angle without observing an error noticeable on fluoroscopy. A second error can occur when the table base angle is used to compensate for the incorrect collimator rotation. These potential sources of error can be avoided if a programmable calculator or computer program is used to assist the dosimetrist during the simulation. Utilization of fluoroscopy, digital table position displays and a caliper provide accurate input for the computer program. This paper will present a hybrid procedure that combines practical set-up procedures with the mathematical calculation of ideal angles to result in an accurate and practical approach to breast simulation.

Breast Neoplasms↗