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At least 109 records · Page 6Linked to original sources
PubMed2005

Registration of three-dimensional left atrial computed tomographic images with projection images obtained using fluoroscopy.

BACKGROUND: Anatomic structures such as the left atrium and the pulmonary veins (PVs) are not delineated by fluoroscopy because there is no contrast differentiation between them and the surrounding anatomy. Representation of an anatomic structure via a 3D model obtained from computed tomography (CT) imaging and subsequent projection of these images over the fluoroscopy system may help in navigation of the mapping and ablation catheter to the appropriate sites during electrophysiology procedures. METHODS AND RESULTS: In this feasibility study, in vitro experiments were performed with a plastic heart model (phantom) with 2 catheters or radiopaque platinum beads placed in the phantom at the time of CT imaging and fluoroscopy. Subsequently, 20 consecutive patients underwent contrast-enhanced, ECG-gated CT scanning. Left atrial volumes were generated from the reconstructed data at &75% of the R-R interval during the cardiac cycle. Similarly, the superior vena cava and the coronary sinus were also reconstructed from these images. During the electrophysiology procedure, digital records (cine sequences) were obtained. Using predetermined algorithms, both the phantom model and the patients' 3D left atrial models derived from the CT were registered with projection images of fluoroscopy. Registration was performed with a transformation that linked the superior vena cava and the coronary sinus from the CT model with a catheter placed inside the coronary sinus via the superior vena cava. Registration was successfully accomplished with the plastic phantom and in all 20 patients. Registration accuracy was assessed in the phantom by assessing the overlapping beads seen both in the CT and the fluoroscopy images. The mean registration error was 1.4 mm (range 0.9 to 2.3 mm). Accuracy of the registered images was assessed in patients with recordings from a basket catheter placed sequentially in the superior PVs and by injecting contrast into the PVs to assess overlapping of contrast-filled PVs with the corresponding vessels on the registered images. The images could be calibrated quite accurately. Any rotational error, which was usually minor, could be corrected by rotating the images as needed. CONCLUSIONS: Registration of 3D models of the left atrium and PVs with fluoroscopic images of the same is feasible and could enable appropriate navigation and localization of the mapping and ablation catheter during procedures such as atrial fibrillation ablation.

Aged↗
PubMed2001

Accuracy of detecting screw penetration of the acetabulum with intraoperative fluoroscopy and computed tomography.

BACKGROUND: The purpose of this study was to determine the accuracy of computed tomography and fluoroscopy in assessing joint penetration by periacetabular screws. METHODS: A 3.5-mm acetabular periarticular screw was inserted in each of thirty-nine cadaveric hemipelves. Twenty screws were intentionally directed to violate the articular surface, whereas nineteen screws were positioned to avoid the articular surface. Using two fluoroscopic views (tangential and axial) in a manner simulating the clinical setting, an examiner blinded to the actual screw location determined whether each screw was violating the articular surface. In addition, each hemipelvis was examined with computed tomography with use of two different techniques: (1) a 1-mm slice thickness at 1-mm intervals, and (2) a 4-mm slice thickness at 3-mm intervals. Each scan was evaluated by another examiner who was blinded to the actual screw location. Sensitivity, specificity, and percent correct interpretations were then calculated for each method. RESULTS: The sensitivity, specificity, and percent correct interpretations were 95%, 84%, and 90%, respectively, for axial fluoroscopy; 85%, 89%, and 87% for tangential fluoroscopy; 100%, 84%, and 92% for the computed tomography scans with a 1-mm slice thickness at 1-mm intervals; and 100%, 58%, and 79% for the computed tomography scans with a 4-mm slice thickness at 3-mm intervals. Tangential fluoroscopy was found to be more specific than the computed tomography scans with a 4-mm slice thickness at 3-mm intervals (p = 0.02). No other significant differences were found. CONCLUSIONS: Fluoroscopy and computed tomography are equally accurate for determining intra-articular screw penetration. Computed tomography scans with thick slices (4 mm at 3-mm intervals) have a low specificity. Their use postoperatively may lead to a false-positive interpretation of the scan and unnecessary exploration of a hip for screw penetration.

Acetabulum↗
PubMed2001

Is sedation safe during dynamic sleep fluoroscopy of children with obstructive sleep apnea?

OBJECTIVE: Airway compromise is considered a relative contraindication for pediatric sedation. This contraindication presents a paradoxical problem when patients require sedation in preparation for imaging performed to evaluate the cause of airway obstruction. We use dynamic sleep fluoroscopy in the evaluation of children who have obstructive sleep apnea. The purpose of this study was to evaluate the success and safety of a structured sedation program for dynamic sleep fluoroscopy. MATERIALS AND METHODS: Eighty consecutive dynamic sleep fluoroscopic studies were evaluated. The type of sedation used, success rate, complications related to the sedation, and characteristics of the children studied were reviewed. Patients were sedated in accordance with our departmental sedation program guidelines. Findings on fluoroscopy were correlated with episodes of oxygen desaturation or noisy breathing. RESULTS: In all 80 cases, dynamic sleep fluoroscopy was successfully performed. Seventy-two studies were performed, with sedation supervised by the radiologist. Four patients fell asleep without sedation. In four patients, sedation was performed by an anesthesiologist (preprocedural decision). Sixty-four children (80%) had complex medical problems, and 39 (49%) had a history of previous airway surgery. All studies were considered successful. Specific diagnoses were identified in 66 children (83%). No children suffered complications or required tracheal intubation. CONCLUSION: Children with airway compromise who are being evaluated for obstructive sleep apnea can be successfully and safely sedated for dynamic sleep fluoroscopy when a structured sedation program is used.

Child, Preschool↗
PubMed1999

Ultrasound-fluoroscopy guided access to the intrarenal excretory system.

The access to the collecting system can be performed under fluoroscopy computerized tomography, ultrasonographic, mixed ultrasonographic and fluoroscopic guidance. In this paper the creation of a percutaneous transparenchymal ultrasound-fluoroscopy guided access to the intrarenal collecting system completely performed by urologist for different purposes is presented. In five years 297 patients underwent 330 percutaneous kidney accesses to perform derivative nephrostomies (217 pts), percutaneous nephrolithotomies (37 pts), antegrade ureteral manoeuvres (34 pts), antegrade endopyelotomies (7 pts), transitional cell carcinoma of the upper tract resection (2 pts). 11 patients out of these had a percutaneous kidney access in a transplanted kidney. The percutaneous access was successful in 98% of the attemps. A posterior calyx of the lower group (74%), of the medium group (25%) or of the upper group (1%) was accessed. In 73 accesses the mean target calyx diameter was 12.8 mm (range 5-45 mm), the mean operative time 5.4 minutes and the mean fluoroscopy time 5.1 seconds. In 84.5% of the patients the access was performed under local anesthesia when a dilation of the tract was not required. Gross haematuria was observed in 3.9% of the accesses and an arterial lesion treated by embolization in 0.9% of the accesses. Blood transfusion was required in 0.3% of the patients. The ultrasound-fluoroscopy guided access is at least as precise as the fluoroscopy guided one moreover it makes the procedure less invasive and it makes more precise the surgical planning.

Fluoroscopy↗
PubMed2000

Transbronchial needle aspiration: guidance with CT fluoroscopy.

BACKGROUND: Bronchoscopy with transbronchial needle aspiration (TBNA) is valuable to diagnose lesions in the mediastinum and lung, but conventional fluoroscopic guidance may be suboptimal. We describe the use of CT fluoroscopy to provide real-time, transaxial TBNA localization, thus facilitating biopsy. METHODS: Patients were selected because of prior unsuccessful bronchoscopy or anticipated difficulty owing to small size or inaccessibility of the lesion. CT fluoroscopy consists of a spiral CT scanner adapted using a rapid-reconstruction algorithm and hardware that permits real-time in-room imaging. The bronchoscope was inserted on the CT scanner, which was used to guide TBNA instruments into the target lesion. RESULTS: Of 27 patients who underwent TBNA with CT fluoroscopic assistance, 15 had mediastinal nodes, and 12 had lung nodules or focal infiltrates. Mean lesion size was 1.7 cm in the mediastinum, 2. 2 cm in the lung. A correct diagnosis was established in 10 of 12 mediastinal lesions (83%) for which follow-up was available and in 8 lung lesions (67%). Diagnoses included small cell and non-small cell lung cancer and invasive aspergillosis. False-negative results were caused by sampling errors or inability to reach the lesion as documented by CT fluoroscopy. Postprocedure CT fluoroscopy revealed no complications. CONCLUSION: CT fluoroscopy provides effective, real-time guidance for TBNA and may be particularly valuable in patients with small or less accessible mediastinal or lung lesions.

Adult↗
PubMed2001

Fluoroscopy-guided lumbar puncture: decreased frequency of traumatic tap and implications for the assessment of CT-negative acute subarachnoid hemorrhage.

BACKGROUND AND PURPOSE: In patients with suspected subarachnoid hemorrhage (SAH) and negative CT findings, the iatrogenic introduction of RBCs into the CSF during lumbar puncture may lead to a misdiagnosis. We tested the hypothesis that the risk of traumatic lumbar puncture is lower with the fluoroscopy-guided technique than with the standard bedside technique. METHODS: Data were collected retrospectively from two populations: adult inpatients undergoing standard bedside lumbar puncture for any reason and adult patients undergoing fluoroscopy-guided lumbar puncture for myelography. Patients with SAH and CSF samples with significant abnormalities other than erythrocytosis (ie, CSF leukocytosis, xanthochromia, or elevated protein) were excluded. In all, 1489 bedside procedures and 723 fluoroscopy-guided procedures met the criteria. RESULTS: We found a significant difference in the level of iatrogenic CSF erythrocytosis produced by the two procedures. Using a cutoff of 1000 cells/mm(3), the frequency of traumatic lumbar puncture was 10.1% for bedside lumbar puncture and 3.5% for fluoroscopy-guided lumbar puncture. With fluoroscopic guidance, the frequency of a traumatic tap varied significantly with the operator, ranging from 0% to 24%. CONCLUSION: The use of fluoroscopy-guided lumbar puncture in patients with suspected SAH and negative CT findings should reduce the frequency of false-positive diagnoses of acute SAH as well as the number of unnecessary angiograms for patients with suspected SAH but no underlying intracranial vascular malformation.

Fluoroscopy↗
PubMed2004

Lyon Schuss radiographic view of the knee. Utility of fluoroscopy for the quality of tibial plateau alignment.

OBJECTIVE: The "Lyon schuss" (LS) view is a fluoroscopically assisted radiographic technique of the knee in flexion. The quality of medial tibial plateau (MTP) alignment is a key element for accuracy and sensitivity to change of knee radiography. We collected data on the geometry of the osteoarthritic (OA) knee when positioned under fluoroscopy according to the LS protocol, then applied the results to develop an angulation standard for a nonfluoroscopically guided examination, and evaluated the performance of fluoroscopic and nonfluoroscopic alternatives for good alignment of the MTP. METHODS: 1. For 50 patients with knee pain (100 knee radiographs): Standardized radiographic procedure under fluoroscopy (LS view and lateral weight-bearing radiograph of the 2 knees); measurement of the tibial plateau inclination with the horizontal (TPI-h); evaluation of the quality of MTP alignment; assessment of the mean x-ray beam angle to obtain satisfactory MTP alignment. 2. For 30 patients with knee OA: LS radiograph of the knee performed without fluoroscopy, using a fixed 11 degrees downward x-ray beam angle (mean value of the angle obtained in the first part of the study) and standardized procedure; then assessment of the quality of MTP alignment. RESULTS: With the fluoroscopically assisted protocol, MTP alignment was satisfactory in 88% of cases. The mean x-ray beam angle was 11.2 degrees downward (SD 3.3 degrees, range 4-22 degrees ) and was unrelated to sex, height, weight, body mass index, and joint space width. The mean TPI-h was 19.6 degrees (SD 6.9 degrees, range 3-35 degrees ). Beam angle and TPI-h were correlated only in the satisfactorily aligned radiographs. In the 30 knees radiographed using a standardized procedure without fluoroscopy, the MTP alignment was satisfactory in 60% of cases. CONCLUSION: Fluoroscopy is useful to obtain satisfactory MTP alignment in LS radiographs because of large interindividual variations in anatomy of the knee.

Aged↗
PubMed2005

Value of CT fluoroscopy for lumbar facet blocks.

We compared the diagnostic accuracy of lumbar facet blocks guided by either conventional fluoroscopy or CT fluoroscopy (CTF). Seventy-one blocks were performed with conventional fluoroscopy, and 58 were performed using CTF. Pain scores were measured before and after the procedure. The CTF group had a greater percentage decrease in pain (79.5% +/- 31.1%) than did the conventional fluoroscopy group (55.5% +/- 38.0%; P < .0005). We conclude lumbar facet blocks by using CTF guidance results in greater diagnostic accuracy than do conventional fluoroscopy.

Adolescent↗
PubMed2006

[Intra-operative fluoroscopy for detecting pedicle screw violation in lumbar vertebrae by guided pin axial position].

OBJECTIVES: To develop an applicable and accurate intra-operative fluoroscopical angle to observe the placement of pedicle screw and pedicle violation. METHODS: Lateral radiographs were taken on eighty lumbar pedicles in eight cadaveric vertebral specimens to measure the sagittal pedicle angles. The pedicles of the vertebral arch were scanned by computed tomography (CT) to measure the transverse pedicle angles. Guided pins and pedicle screws were inserted by awl into the pedicles through the holes drilled in the lumbar pedicles so as to establish 3 types of model: medial violation (n = 29), lateral violation (n = 25), and properly placed screw (n = 26) the anterior and posterior portions of the lumbar pedicle cortex could be identified by the fluoroscopy C-arm. Fluoroscopy with the aid of C-arm was taken on each pedicle in five different directions: lateral position; anteroposterior position; pedicle axial position; guided pin axial position; and pedicle screw axial position. The positions of guided pin and pedicle screw were evaluated. The gold standard was acquired by excising the vertebral plate and observing directly. RESULTS: Nine cases of medial violation were discovered and the accuracy rate was 33.75% by anteroposterior fluoroscopy. The accuracy rate was 95% by the pedicle axial fluoroscopes, including 4 cases of medial inclination but properly placed screws were mistaken for medial violation by pedicle axial fluoroscope. The accuracy rate was 100% by guided pin axial position fluoroscopy, including 29 cases of medial violations, 25 cases of lateral violation, and 26 cases of properly placed screws. CONCLUSION: The approach of intra-operative fluoroscopy of guided pin axial position is a reliable technology for detecting pedicle violation with the aid of C-arm. The incidence of flexible pedicle screw from human factors can be reduced.

Adult↗
PubMed1989

[Radiographic examination of the thorax, fluoroscopy and echocardiography in cardiac calcification].

The value of radiographic examination of the thorax, fluoroscopy and echocardiography in demonstration and localization of intracardiac calcifications were compared in an investigation of 40 patients with valvular heart disease prior to planned cardiac catheterization or operation. Radiographic examination of the thorax revealed only the most severe calcifications. By means of echocardiography it proved possible to undertake a simple semi-quantitative characterisation of the calcified tissue with acceptable intra- and inter-observer variation. Echocardiography and fluoroscopy were found to be of equal value in demonstration of the degree of calcification of the heart. Echocardiography was, however, superior to fluoroscopy in fine localization of the calcifications. The relative and additive values of the methods could be illustrated employing Bayes' theorem and could be represented graphically provided that the observations carried out with the three methods could be considered independent of one another. It is concluded that radiographic examinations of the thorax is unsuitable for screening for cardiac calcifications. Fluoroscopy can no longer be considered to be the method of choice in assessing lesions of this type but should be employed in cases where echocardiography does not provide sufficient information or is not available. The greatest certainty in demonstration of calcifications is obtained with combined employment of fluoroscopy and echocardiography.

Adult↗
PubMed1995

[Evaluation of sleep apnea syndrome (SAS) with low field MR fluoroscopy].

Eight cases of clinically diagnosed sleep apnea syndrome (SAS) and two normal volunteers were studied with low field MR fluoroscopy in order to monitor the waking and sleeping status of the upper airway. MR fluoroscopy revealed that only the sleeping patients showed occlusions of the upper airway. This technique provided us with useful information about the level, frequency and duration of occlusion in each case. Four of the eight patients demonstrated simple retropalatal occlusion, whereas the other four demonstrated mixed retropalatal and retropalato-retroglossal occlusion. Thus long-time monitoring, which is only possible with MR fluoroscopy, is needed to appreciate the complex nature of the disease. In addition, the comfortable surroundings and low noise level provided by the low field enabled physiological study to be performed without any tranquilizers in most of the patients, which is again only possible with MR fluoroscopy. MR fluoroscopy may become a tool of great clinical value, providing much important information for disease evaluation and treatment selection.

Adult↗
PubMed2001

The practical application of signal detection theory to image quality assessment in x-ray image intensifier-TV fluoroscopy.

This paper applies a published version of signal detection theory to x-ray image intensifier fluoroscopy data and compares the results with more conventional subjective image quality measures. An eight-bit digital framestore was used to acquire temporally contiguous frames of fluoroscopy data from which the modulation transfer function (MTF(u)) and noise power spectrum were established. These parameters were then combined to give detective quantum efficiency (DQE(u)) and used in conjunction with signal detection theory to calculate contrast-detail performance. DQE(u) was found to lie between 0.1 and 0.5 for a range of fluoroscopy systems. Two separate image quality experiments were then performed in order to assess the correspondence between the objective and subjective methods. First, image quality for a given fluoroscopy system was studied as a function of doserate using objective parameters and a standard subjective contrast-detail method. Following this, the two approaches were used to assess three different fluoroscopy units. Agreement between objective and subjective methods was good; doserate changes were modelled correctly while both methods ranked the three systems consistently.

Biophysical Phenomena↗
PubMed2003

Real-time adaptive filtering for projection reconstruction MR fluoroscopy.

Magnetic resonance (MR) imaging has faced a dramatic increase in real-time capabilities over the last years. However, the application of fast pulse sequences still suffers from low signal-to-noise ratios (SNRs), which can be the limiting factor for the actual acquisition speed. In MR fluoroscopy, filtering along the time and/or spatial domain can be applied to increase the image quality. In this paper, a projection-based noise filter is presented that significantly enhances the SNR in projection reconstruction (PR) fluoroscopy without apparent loss of resolution in the reconstructed images. In contrast to an imaged-based approach, this method allows a very efficient computational implementation. The filter algorithm was implemented on a digital signal processor and was applied to real-time processing during PR fluoroscopy. A quantitative analysis of the improvement in SNR and results for different fluoroscopic MR applications are given. Apart from MR fluoroscopy, the proposed technique has the potential to be applied to low dose computed tomography fluoroscopy.

Algorithms↗
PubMed2003

Magnetic resonance fluoroscopy allows targeted delivery of mesenchymal stem cells to infarct borders in Swine.

BACKGROUND: The local environment of delivered mesenchymal stem cells (MSCs) may affect their ultimate phenotype. MR fluoroscopy has the potential to guide intramyocardial MSC injection to desirable targets, such as the border between infarcted and normal tissue. We tested the ability to (1) identify infarcts, (2) navigate injection catheters to preselected targets, (3) inject safely even into fresh infarcts, and (4) confirm injection success immediately. METHODS AND RESULTS: A 1.5-T MRI scanner was customized for interventional use, with rapid imaging, independent color highlighting of catheter channels, multiple-slice 3D rendering, catheter-only viewing mode, and infarct-enhanced imaging. MRI receiver coils were incorporated into guiding catheters and injection needles. These devices were tested for heating and used for targeted MSC delivery. In infarcted pigs, myocardium was targeted by MR fluoroscopy. Infarct-enhanced imaging included both saturation preparation MRI after intravenous gadolinium and wall motion. Porcine MSCs were MRI-labeled with iron-fluorescent particles. Catheter navigation and multiple cell injections were performed entirely with MR fluoroscopy at 8 frames/s with 1.7x3.3x8-mm voxels. Infarct-enhanced MR fluoroscopy permitted excellent delineation of infarct borders. All injections were safely and successfully delivered to their preselected targets, including infarct borders. Iron-fluorescent particle-labeled MSCs were readily visible on delivery in vivo and post mortem. CONCLUSIONS: Precise targeted delivery of potentially regenerative cellular treatments to recent myocardial infarction borders is feasible with an MR catheter delivery system. MR fluoroscopy permits visualization of catheter navigation, myocardial function, infarct borders, and labeled cells after injection.

Animals↗
PubMed2002

Measurement and correction of the effects of lag on contrast-detail test results in fluoroscopy.

Persistence of the video signal between TV frames, an effect also known as image lag, can lead to anomalously good contrast-detail test results for fluoroscopy systems. In this practical paper, a simple method is described which quantifies lag in fluoroscopy systems and corrects for its effect on threshold contrast. A digital framestore was used to acquire temporally contiguous fluoroscopy images. Correlation of the variance between an initial base TV frame and successive later frames was then measured via the correlation coefficient. Plotted against time, this function defines a time constant which characterizes the rate at which the initial variance pattern is replaced by incoming quantum noise. A survey of seven fluoroscopy units incorporating vacuum TV camera tubes found a mean time constant of 0.06 s. The relative change in contrast-detail performance was then measured as a function of applied digital frame averaging for two separate fluoroscopy units. A time constant was found for each frame averaging mode using the correlation of variance between frames. These measurements were used to derive a function which corrects contrast-detail results obtained for a unit with a measured nominal time constant to the typical vacuum camera tube time constant of 0.06 s. The correction is shown to significantly reduce the spread of contrast-detail results obtained over a range of temporal filtration settings.

Algorithms↗
PubMed2000

Accurate placement of the distal end of a ventriculoatrial shunt catheter using Alphacard: direct intraoperative comparison with fluoroscopy.

BACKGROUND: Surgical insertion of a ventriculoatrial shunt requires accurate placement of the atrial catheter in the right atrium in order to prevent postoperative complications. Fluoroscopy is the standard method for monitoring correct positioning of the catheter. METHODS: This paper reports a prospective study in 50 patients with the aim of comparing electrocardiographic monitoring of the catheter position by means of Alphacard with concomitant intraoperative fluoroscopic examination. The Alphacard was evaluated in terms of accuracy, time requirement, and ease of handling. The mean postoperative follow-up period was 54 (range 42-66) months. FINDINGS: Reliable control of the catheter position was possible by means of electrocardiographic guidance in all 50 patients (100%) by fluoroscopy in 49 cases (98%). The average time required for intra-operative monitoring of the catheter position was 55 (40-70) seconds for electrocardiography as compared to 8 (5-12) minutes for fluoroscopy. None of the patients showed obstruction of the atrial catheter during the postoperative follow-up period. INTERPRETATION: Alphacard offers an excellent alternative for monitoring the position of the tip of an atrial catheter because it requires little equipment and time. In terms of reliability, it is comparable or even superior to fluoroscopy.

Adolescent↗
PubMed2006

Effect of physician training on fluoroscopy time during ERCP.

Our purpose was to compare fluoroscopy time during endoscopic retrograde cholangiopancreatography (ERCP) between endoscopists with different levels of experience. We performed a cross-sectional analysis of 269 consecutive ERCPs at an academic hospital during 1 year. Median fluoroscopy time was significantly longer in more complex cases, such as in therapeutic (406.5 s [IQR, 235.5-685]) compared to diagnostic (202 s [IQR, 141-481]; P = 0.002) procedures. The experience (number of prior ERCPs) of gastroenterology fellows involved in procedures was an independent predictor of shorter fluoroscopy time when controlling for patient and procedure characteristics (P < 0.0001). Median fluoroscopy time was 2.73 min shorter after at least 50 procedures had been performed (P = 0.039). Time for ERCPs involving fellows was not significantly longer than cases by attending physicians alone (P = 0.23). Increased experience is associated with lower radiation exposure during ERCP training. Radiation reduction methods should be prospectively investigated and integrated into training programs.

Cholangiopancreatography, Endoscopic Retrograde↗
PubMed1988

Value of fluoroscopy in the detection of coronary stenosis: influence of age, sex, and number of vessels calcified on diagnostic efficacy.

Although fluoroscopically detected coronary artery calcification is known to correlate with the presence of coronary artery stenosis, age, sex, and extent of calcification influence the strength of this association. To clarify its diagnostic potential, we performed fluoroscopy before coronary angiography in 600 patients and analyzed the results according to all three factors simultaneously. The sensitivity of fluoroscopy for significant stenosis exceeded 65% in all groups except women less than 45 years of age. Specificity exceeded 90% in patients less than 45 years and 85% in patients less than 55 years of age, and declined significantly with age. The number of vessels calcified was an important determinant of predictive value, except in those less than 45 years of age in whom even a single mild calcification markedly increased the chance of stenosis. In patients aged 45 to 64 years, calcification of two or three vessels substantially increased the chances of stenosis, but single-vessel calcification increased the risk only slightly. In patients more than 65 years of age, fluoroscopy was not helpful in detecting stenosis, regardless of the number of vessels calcified. Our findings were similar in men and women. We conclude that if both age and the number of vessels calcified are considered, fluoroscopy can provide useful information regarding the presence of stenosis in young and middle-aged patients.

Age Factors↗