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PubMed1985

Fluoroscopic and arthrographic evaluation of carpal instability.

The efficacy of a diagnostic protocol involving videotape fluoroscopy of carpal motion and radiocarpal arthrography was evaluated in patients with wrist pain unexplained by physical examination and conventional radiographs. Videotape fluoroscopy was performed as the first study in 68 consecutive cases and was positive in 44 (66%). Radiocarpal arthrography was performed after videotape fluoroscopy in 39 of the cases (57%), including the 24 in which videotape fluoroscopy was normal and 15 others in which further information was desired in spite of positive videotape fluoroscopy. The addition of radiocarpal arthrography to videotape fluoroscopy increased the diagnostic yield to 52 (76%) of the 68 cases and excluded significant anatomic or dynamic abnormality in the others. The diagnosis was proven surgically in 25 cases. This protocol was efficacious for ligament tears of the proximal carpal row, triangular fibrocartilage tears, and proximal and midcarpal instability. Videotape fluoroscopy should be the primary method of evaluating patients with unexplained wrist pain, and arthrography should be done in those cases in which fluoroscopy is either normal or does not fully explain physical findings.

Adolescent↗
PubMed1995

[Reducing radiation dosage with modern DSA equipment].

PURPOSE: In angiographic and interventional procedures the often long fluoroscopy times add a great deal to the total patient dose. The new Multistar T.O.P. (Siemens) is equipped with various features for dose reduction. In this study pulsed fluoroscopy was tested versus standard continuous fluoroscopy and supervisions. MATERIALS AND METHODS: Fluoroscopy with 3, 7.5, and 15 pulses/s in the Multistar T.O.P. were compared to standard fluoroscopy and to reduced-dose supervision in a human pelvic phantom. The skin entry dose and pelvic dose were continuously registered. RESULTS: The supervision mode used 58% of the dose used in continuous fluoroscopy. Pulsed fluoroscopy with 15 pulses/s required 54%, 7.5 pulses/s 27% and 3 pulses/s. These provide adequate image quality with only 10% of the standard dose. CONCLUSIONS: It was possible to save up to 90% of the fluoroscopy dose in interventions and angiographies when using the new pulsed fluoromodes available in the Multistar T.O.P.

Angiography, Digital Subtraction↗
PubMed1994

Observer performance and diagnostic outcome in diagnosis of the disk position of the temporomandibular joint using arthrography.

Observer performance and diagnostic outcome in the diagnosis of the disk position of the temporomandibular joint by arthrography were investigated. Three different radiographic techniques were studied: fluoroscopy, fluoroscopy in combination with lateral transcranial radiography, and fluoroscopy in combination with corrected sagittal tomography. Seven observers were asked to assess 30 joints representing three diagnoses, namely superior disk position and anterior disk position with and without reduction. The intraobserver agreement was high for all three techniques. The interobserver agreement of the seven observers when the disk position was diagnosed by fluoroscopy in combination with lateral transcranial radiography (Kappa index 0.68) was higher than that with fluoroscopy alone (Kappa index 0.54) and that with fluoroscopy in combination with corrected sagittal tomography (Kappa index 0.56). The sensitivity, specificity, and predictive values of fluoroscopy in combination with lateral transcranial radiography were also higher than those of the other radiographic techniques. Judged from this study, the observer agreement and the diagnostic outcome for arthrography with the use of the three examined techniques are high when well-defined criteria and reference images are applied.

Adolescent↗
PubMed2004

Computer aided long bone fracture treatment.

Intraoperative fluoroscopy is the tool for intraoperative control of long bone fracture reduction and osteosynthesis. Limitations of this technology include: High radiation exposure to the patient and the surgical team, limited field of view, image distortion, limitation to 2-D representations, and cumbersome updating of verification images. Fluoroscopy based navigation systems partially address these limitations by allowing fluoroscopic images to be used for real-time surgical localization and instrument tracking. In a clinical study on computer guidance by virtual fluoroscopy for distal locking, the capability to provide online guidance with significantly reduced fluoroscopy times is demonstrated. Virtual fluoroscopy applied for guidewire placement in a laboratory setup demonstrated the potential of the method to reduce procedure times, and the potential to increase precision of implant placement with decreased fluoroscopy times. By using virtual reality enhancement, starting from multiple registered fluoroscopy images, a virtual 3-D cylinder model for each principal bone fragment is reconstructed. This spatial cylinder model is not only used to supply a 3-D image of the fracture, but also allows effective fragment projection extraction from the fluoroscopic images and further achieves radiation-free updates of in-situ surgical fluoroscopic images through a non-linear interpolation and warping algorithm. After primary image acquisition, the image intensifier was replaced by the virtual reality system. It was shown that all the steps of the procedure, including fracture reduction and LISS osteosynthesis can be performed completely in virtual reality.

Fluoroscopy↗
PubMed2006

Incidence of simultaneous epidural and vascular injection during lumbosacral transforaminal epidural injections.

BACKGROUND CONTEXT: The incidence of vascular penetration during contrast confirmed fluoroscopically guided transforaminal lumbosacral epidural injections has been reported as 8.9% to 21.3% depending on the level of injection. Recently, intermittent fluoroscopy was shown to miss more than half of the vascular injections observed under live fluoroscopy. The number of misses increased when epidural and vascular contrast flow appeared simultaneously, even if the fluoroscopic image was taken during contrast injection. To date, no studies have documented the incidence of simultaneous epidural and vascular contrast injections. Also, most previous studies of vascular injections did not document use of live fluoroscopy during contrast injection, so the incidence of vascular injections may be higher than reported. PURPOSE: To determine the incidence of simultaneous epidural and vascular contrast injection during lumbosacral transforaminal epidural injections. STUDY DESIGN/SETTING: A prospective, observational, in vivo, study. PATIENT SAMPLE: Patients receiving lumbar transforaminal epidural injections at a university-based outpatient spine center. OUTCOME MEASURES: Incidence of epidural, vascular, and simultaneous epidural and vascular contrast patterns. METHODS: One interventional spine physician and three fellows under his direct supervision recorded contrast patterns observed during 191 fluoroscopically guided lumbosacral transforaminal epidural steroid injections with injection of contrast observed under live fluoroscopy. RESULTS: The incidence of simultaneous epidural and vascular injection during lumbosacral transforaminal epidural injections was 8.9%. The incidence of a vascular injection alone was 4.2%, for a total vascular injection incidence of 13.1%. Subjects with a simultaneous epidural and vascular injection who returned for repeat injection had a statistically significant chance of a repeat simultaneous epidural and vascular injection when the injection was done at the same location. Fluoroscopy time was significantly increased, an average of 8.8 seconds, when a vascular injection was identified. There was no statistically significant correlation between the incidence of simultaneous epidural and vascular injection with subjects' age, sex, level of injection, side of injection, needle gauge, or diagnosis. CONCLUSIONS: Simultaneous epidural and vascular injection is twice as likely to occur as vascular injection alone. Use of intermittent fluoroscopy can miss the transient appearance of the vascular component of these injections, giving the false impression of successful contrast placement. In light of these results, live fluoroscopy is recommended during contrast injection for confirmation of lumbosacral transforaminal epidural injections.

Adult↗
PubMed2001

Tibial intramedullary nail distal interlocking screw placement: comparison of the free-hand versus distally-based targeting device techniques.

Intramedullary nailing is the standard treatment for closed and some open unstable diaphyseal tibia fractures. Fluoroscopy, while essential for proper nail placement can subject the surgical team and patient to substantial radiation. A new targeting system for tibia nail distal interlocking was developed by Orthofix to limit fluoroscopy. This prospective clinical study compares the Orthofix targeting system versus a free-hand technique for the tibial nail distal interlocking. Fifty eight consecutive patients with sixty tibial fractures amenable for nail fixation were randomly assigned into two equal groups: Group 1: Orthofix distally based distal targeting device and Group 2: a free-hand technique. In all the cases stabilization was achieved with a reamed statically locked tibial nail. Recorded data included accuracy of screw placement, duration of surgery prior to and during distal interlocking, and the fluoroscopy time prior to and during distal interlocking. Both groups revealed comparable fracture patterns. In all fractures the technical aspects of the surgical treatment were performed without complications. There was no statistically significant difference between the groups in the mean time of surgery prior to (62.02 vs. 61.01 min, P=0.92) and during distal interlocking (17.06 vs. 19.08 min, P=0.55), or in the total surgical time (81 vs. 85 min), respectively. Neither was there a statistically significant difference in the mean fluoroscopy time prior to distal interlocking (69 vs. 81 s, p=0.22) nor in the total fluoroscopy time (84 vs. 117 s). There was however, a statistically significant difference between the Orthofix and free-hand groups with regards to the mean fluoroscopy time during distal interlocking (15 vs. 36 s, P=0.01, respectively). This study demonstrates that the distally based distal targeting device by Orthofix for tibial nailing can significantly decrease the mean fluoroscopy time necessary to complete distal interlocking versus free-hand technique.

Adolescent↗
PubMed2005

[Direct percutaneous radiologic jejunostomy (PR) and duodenostomy: a retrospective analysis].

PURPOSE: To present our experience with direct percutaneous radiologic duodenostomy and jejunostomy (PRJ) for alimentation. MATERIALS AND METHODS: A retrospective study identified 24 patients who had undergone percutaneous jejunostomy or duodenostomy guided by CT and fluoroscopy over a period of 9 years. Whenever possible, the jejunum was inflated with a 5 French diagnostic catheter and jejunopexy was performed using Cope anchors (T-fasteners). A 12 to14 French locking pigtail drain was inserted for alimentation. In 8 patients, percutaneous direct jejunostomy was performed using only fluoroscopy. In 9 patients, both CT and fluoroscopy were used to guide the jejunostomy. In all 7 patients who underwent duodenostomy, a combination of CT and fluoroscopy was used. The reports were reviewed for complications and the technical success rate. The technical success rate was determined. RESULTS: Percutaneous radiologic jejunostomy was attempted in 17 patients and failed in 5 patients. PRJ was successful in all 8 procedures guided by fluoroscopy and in 4 of 9 procedures guided by CT and fluoroscopy. Direct percutaneous duodenostomy guided by CT and fluoroscopy was successful in all 7 cases. There were no procedure-related laparotomies and no mortality related to the jejunostomy. Minor complications were infection of the abdominal wall (n = 1), lingering pain requiring a new jejunostomy (n = 1) and aspiration because of persistent reflux (n = 1). CONCLUSION: PRJ is a safe procedure even in critically ill patients. It is technically difficult and may fail if the jejunum cannot be distended. Percutaneous radiologic duodenostomy and jejunostomy are recommended for prolonged alimentation of malnourished patients following esophageal or gastric surgery.

Critical Illness↗
PubMed2006

The use of computerized image guidance in lumbar disk arthroplasty.

OBJECTIVES: Surgical navigation systems have been increasingly studied and applied in the application of spinal instrumentation. Successful disk arthroplasty requires accurate midline and rotational positioning for optimal function and longevity. A surgical simulation study in human cadaver specimens was done to evaluate and compare the accuracy of standard fluoroscopy, computer-assisted fluoroscopic image guidance, and Iso-C3D image guidance in the placement of lumbar intervertebral disk replacements. METHODS: Lumbar intervertebral disk prostheses were placed using three different image guidance techniques in three human cadaver spine specimens at multiple levels. Postinstrumentation accuracy was assessed with thin-cut computed tomography scans. RESULTS: Intervertebral disk replacements placed using the StealthStation with Iso-C3D were more accurately centered than those placed using the StealthStation with FluoroNav and standard fluoroscopy. Intervertebral disk replacements placed with Iso-C3D and FluoroNav had improved rotational divergence compared with standard fluoroscopy. Iso-C3D and FluoroNav had a smaller interprocedure variance than standard fluoroscopy. These results did not approach statistical significance. Relative to both virtual and standard fluoroscopy, use of the StealthStation with Iso-C3D resulted in improved accuracy in centering the lumbar disk prosthesis in the coronal midline. CONCLUSIONS: The StealthStation with FluoroNav appears to be at least equivalent to standard fluoroscopy and may offer improved accuracy with rotational alignment while minimizing radiation exposure to the surgeon. Surgical guidance systems may offer improved accuracy and less interprocedure variation in the placement of intervertebral disk replacements than standard fluoroscopy. Further study regarding surgical navigation systems for intervertebral disk replacement is warranted.

Aged↗
PubMed1999

Does fractionation decrease the risk of breast cancer induced by low-LET radiation?

Whether fractionation decreases the risk of breast cancer induced by low-LET radiation is a question of some importance. Analyses of the data for TB cohorts who were exposed to multiple fluoroscopies show an apparently similar breast cancer risk compared with those for the acutely exposed A-bomb survivors. However, the fluoroscopy cohorts were subjected to very much lower-energy photons (60-80 kVp) compared with the A-bomb survivors; the increased RBE associated with the low photon energies to which these fluoroscopy cohorts were exposed suggests that, in comparison to the risk estimates for the A-bomb survivors, the risk estimates from the X-ray fluoroscopy cohorts are increased because of the lower-energy X rays and decreased by a similar amount due to fractionation, resulting in an overall apparent equality of risk. Thus the results from the most powerful epidemiological data sets available for assessing breast cancer risks after fractionated exposure to low-LET radiation (the fluoroscopy cohorts) are quite consistent with a lower radiation risk for a fractionated exposure in comparison to an acute exposure. In general, for any cancer site, estimates of the dose-rate effectiveness factor (DDREF) generated by comparing the results for A-bomb survivors with those for the TB fluoroscopy cohorts should probably be roughly doubled from their apparent values because of the increased RBE of the fluoroscopy X rays.

Breast Neoplasms↗
PubMed2002

Radiation exposure to the physician in interventional pain management.

Fluoroscopy is an integral part of the practice of interventional pain management in present day modern medical practices. The major purpose of fluoroscopy in interventional pain management is correct needle placement to ensure target specificity and accurate delivery of the injectate. Fluoroscopy has become mandatory for multiple procedures based either on the definition of the procedure or the requirement of third parties. The most commonly used fluoroscopy in interventional pain management is with C-arm fluoroscopes with image intensification. Fluoroscopy is associated with risk for patients, clinicians, and the personnel in the operating room unless it is managed with appropriate understanding, skill, and vigilance. A total of 1,000 consecutive patients undergoing interventional procedures with chronic pain performed by one physician were studied. Two fluoroscopy units were utilized and operated by two certified radiological technologists. The procedures performed included caudal and interlaminar epidural injections, facet joint nerve blocks, percutaneous adhesiolysis, intercostal nerve blocks, sympathetic blocks, transforaminal epidural injections, along with other procedures. Results showed that a total of 1,000 patients underwent 1,729 procedures with average radiation exposure of 13.2 +/- 0.33 seconds per patient and 7.7 +/- 0.21 seconds per procedure. Dosimetry measurements showed total exposure of 1,345 mREM outside the apron and 0 mREM inside the apron during this period. The average exposure outside the apron was 1.345 mREM per patient and 0.778 mREM per procedure outside the apron and 0 mREM inside the apron. The levels of exposure are significantly below the annual limits recommended. It is concluded that it is feasible to perform all procedures under fluoroscopy in the described setting safely and effectively in interventional pain management.

Journal Article↗
PubMed2005

Pediatric patient surface doses in neuroangiography.

BACKGROUND: Neuroangiographic techniques (diagnostic and interventional) can be lengthy and complex and can be associated with high radiation entrance skin doses from fluoroscopy and digital subtraction angiography (DSA). OBJECTIVE: To measure entrance surface doses received by pediatric patients undergoing neuroangiographic procedures and to (1) compare these doses with thresholds for deterministic effects, (2) compare these doses with those reported in adults, and (3) to understand the dose relationships among diagnostic and interventional procedures, DSA and fluoroscopy. MATERIALS AND METHODS: A neurobiplane unit with fluoroscopic and DSA capabilities was used for all neuroangiographic procedures. An automated patient dosimeter, installed on both planes of the unit, calculated maximum surface dose. The dosimeter also recorded the number of angiographic frames and the length of fluoroscopy time for each procedure. RESULTS: This retrospective study analyzed entrance surface doses to 100 pediatric patients, 76 of whom underwent neuroangiographic diagnostic procedures and 24 of whom underwent neuroangiographic interventional procedures. The DSA acquisitions ranged from 44 frames to 1,428 frames per procedure and fluoroscopy times ranged from 1.1 to 85.6 min per procedure. The mean surface dose from fluoroscopy was 68.1 mGy (max: 397.1 mGy) in the frontal (PA) plane; in the lateral (LAT) plane, the mean surface dose was 40.9 mGy (max: 418.5 mGy). The mean surface doses from DSA were 263.1 and 126.9 mGy in the frontal and lateral planes, with maximum doses of 924.4 and 410.1 mGy, respectively. Mean fluoroscopy dose rates were 5.4 mGy/min in the PA plane and 4.7 mGy/min in the LAT plane. The DSA largely contributed to the overall procedural surface dose, accounting for 82% of the combined surface dose in the each of the imaging planes. CONCLUSION: The surface dose for each procedure measured in this study was found to be below thresholds for deterministic effects. Interventional procedures consistently yield the highest doses.

Adolescent↗
PubMed2000

Optimization of a fluoroscope to reduce radiation exposure in pediatric imaging.

BACKGROUND: A new children's hospital provided the impetus to investigate radiation dose and image quality in a fluoroscope that was specially engineered for pediatric fluoroscopy. Radiation protection management recommends radiation exposures that are as low as reasonably achievable, while still maintaining diagnostic image quality. OBJECTIVES: To obtain comparative phantom imaging data on radiation exposure and image quality from a newly installed fluoroscope before and after optimization for pediatric imaging. MATERIALS AND METHODS: Images were acquired from various thickness phantoms, simulating differing patient sizes. The images were evaluated for visualization of high- and low-contrast objects and for radiation exposure. Effects due to use of the image intensifier anti-scatter grid were also investigated. RESULTS: The optimization of the new fluoroscope for pediatric operation reduced radiation exposure by about 50% (compared to the originally installed fluoroscope), with very little loss of image quality. Pulsed fluoroscopy was able to lower radiation dose to less than 10% of continuous fluoroscopy, while still maintaining acceptable phantom image quality. CONCLUSION: Radiation exposure in pediatric fluoroscopy can be reduced to values well below the exposure settings that are typically found on unoptimized fluoroscopes. Pulsed fluoroscopy is considered a requisite for optimal pediatric fluoroscopy.

Adult↗
PubMed1994

Modifying fluoroscopic views reduces operator radiation exposure during coronary angioplasty.

OBJECTIVES: This three-part study examined the feasibility of reducing operator radiation exposure during coronary angioplasty. BACKGROUND: As case loads and complexity increase, some cardiologists are receiving increasing radiation scatter doses. Techniques to reduce this are therefore becoming more important. METHODS: First, the determinants of the operator dose were assessed by measuring the differences in scatter dose with different camera views. The relative contribution of fluoroscopy as opposed to cine was then quantified. Finally, operators were provided with these data, and subsequent changes in technique were evaluated. RESULTS: Left anterior oblique views resulted in 2.6 to 6.1 times the operator dose of equivalently angled right anterior oblique views. Increasing steepness of the left anterior oblique view also resulted in a progressive increase in operator dose, with left anterior oblique 90 degrees causing eight times the dose of left anterior oblique 30 degrees and three times that of left anterior oblique 60 degrees. In the 45 coronary angioplasty cases prospectively analyzed, fluoroscopy was found to be a greater source of total radiation than cine by a 6.3:1 ratio (range 1.1 to 15.8). Once operators were made aware of the importance of left anterior oblique fluoroscopy, there was a marked reduction in its use. When this was not feasible, there was a reduction in the steepness of the angulation. Left anterior oblique fluoroscopy during angioplasty of the left anterior descending and circumflex coronary arteries was reduced from 40% of total screening time to approximately 5%, and left anterior oblique angulation for fluoroscopy during angioplasty of the right coronary artery decreased from 43.6 degrees (+/- 9.1 degrees) to 29.4 degrees (+/- 2.2 degrees). Success rates (90% vs. 89%) and screening times (19.5 vs. 20.7 min) remained unchanged in 200 coronary angioplasties performed after the study. Average operator radiation dose (measured by radiation badges worn under lead at waist level) was reduced from 32.6 to 14.3 microSv/operator per week despite a slight increase in case load. CONCLUSIONS: Fluoroscopy is the major source of total radiation exposure during coronary angioplasty, with left anterior oblique views providing the highest dose. Modification of views is feasible and will result in significant reduction of operator radiation dose.

Angioplasty, Balloon↗
PubMed2002

Radiation exposure using laser aiming guide in orthopaedic procedures.

BACKGROUND: Ionizing radiation from intraoperative fluoroscopy presents a serious occupational health and safety concern to orthopaedic surgeons.The long-term effects of ionizing radiation are well known; they include damage to the eyes, increased risk of haematological malignancy and carcinomas throughout the body. We studied the effect of using an attachable laser aiming guide on radiation exposure during intraoperative fluoroscopy. METHODS: A prospective, randomized controlled trial was performed at a single institution. Eight hundred and eighty consecutive orthopaedic procedures involving fluoroscopy were randomized into two groups. One group had fluoroscopy without an aiming guide, the other group had fluoroscopy with the aiming guide. Total exposure time, number of exposures and the body region examined were recorded. RESULTS: For most regions studied, no significant difference in exposure time or number of exposures was found. For hip fractures, use of the laser aiming device was associated with an increase in the number of exposures (P = 0.035), but there was no significant difference in average exposure time (P = 0.31). Use of the aiming device was associated with an increased number of exposures (P = 0.0025) and an increased exposure time (P = 0.0016)for examination of the wrist, but this may represent selection bias. CONCLUSION: Use of a laser aiming device during intraoperative fluoroscopy was not associated with decreased exposure to radiation.

Fluoroscopy↗
PubMed2003

Pulmonary vein disconnection using the LocaLisa three-dimensional nonfluoroscopic catheter imaging system.

INTRODUCTION: Catheter ablation for atrial fibrillation (AF) is associated with prolonged fluoroscopy times. We prospectively evaluated the use of the LocaLisa three-dimensional nonfluoroscopic catheter imaging system with the aim of reducing fluoroscopy times during pulmonary vein (PV) disconnection. METHODS AND RESULTS: Fifty-two patients with AF (47 men and 5 women, mean age 53 +/- 9 years) underwent disconnection of all four PVs guided by a circumferential mapping catheter. The LocaLisa navigation system was used for real-time three-dimensional nonfluoroscopic imaging of the circumferential mapping catheter and ablation catheter electrodes in 26 patients. Procedural parameters were compared with those of a control group consisting of 26 patients in whom only standard fluoroscopy was used. PV disconnection was performed similarly in both groups by circumferential ablation around the ostia, with the endpoint of disconnecting left atrium to PV breakthroughs. The cumulative duration of radiofrequency (RF) energy delivery, procedural time, and fluoroscopy time required for PV disconnection were compared. Successful disconnection was achieved in all PVs, without acute complications. There was no significant difference in cumulative RF energy delivery: 34.8 +/- 11.4 minutes for the nonfluoroscopic imaging group versus 38.2 +/- 10.5 minutes for the control group. The fluoroscopy time required for disconnection of all four PVs was significantly lower in the LocaLisa group than in the control group: 8.4 +/- 4.3 minutes versus 23.7 +/- 9.7 minutes (P < 0.0001). There also was a significant difference in the mean time taken for PV disconnection: 46.5 +/- 12.0 minutes for the nonfluoroscopic imaging group versus 66.3 +/- 18.9 minutes for the control group (P < 0.0001). CONCLUSION: By allowing continuous three-dimensional monitoring of ablation and mapping catheter position and orientation, the LocaLisa nonfluoroscopic imaging system significantly reduces fluoroscopy and PV disconnection times.

Atrial Fibrillation↗
PubMed2006

An evaluation of image-guided technologies in the placement of percutaneous iliosacral screws.

STUDY DESIGN: A surgical simulation study in human cadaver spine specimens was conducted to evaluate the accuracy of 3 different surgical navigation systems compared to standard fluoroscopy in the percutaneous placement of iliosacral screws. OBJECTIVES: To compare the accuracy of percutaneous iliosacral screw placement using standard fluoroscopy, computer-assisted fluoroscopic image guidance, Iso-C3D image guidance (Medtronic Surgical Navigation Technologies, Louisville, CO), and electromagnetic fluoroscopic image guidance. SUMMARY OF BACKGROUND DATA: Conventional percutaneous sacroiliac screw placement has a malposition rate as high as 15%, as reported in the English-speaking literature (Hinsche et al [Clin Orthop Relat Res 2002;395:135-44] and Templeman et al [Clin Orthop Relat Res 1996;329:194-8]). Iso-C3D and computer-assisted image guidance technologies have been proposed to increase this accuracy rate. METHODS: Two iliosacral screws were placed bilaterally (4 screws) in each of 4 cadavers using standard fluoroscopy, computer-assisted fluoroscopic image guidance, Iso-C3D image guidance, and electromagnetic fluoroscopic image guidance. Screw positions were analyzed by computerized tomography after instrumentation and assigned a score based on deviation from ideal screw position. RESULTS: The StealthStation with FluoroNav (Medtronic Surgical Navigation Technologies) appeared to provide the highest accuracy of all guidance techniques. This result was more accurate than standard fluoroscopy. CONCLUSIONS: Computer-assisted fluoroscopy based image navigation appears to be more accurate than standard fluoroscopy in placing these screws. However, errors may occur with all techniques. Further refinement in registration procedures may highly improve the accuracy of percutaneous screw placement in a variety of spinopelvic procedures.

Aged↗
PubMed2004

Does fluoroscopic imaging still have a role in colonoscopy?

GOAL: To assess the use and value of fluoroscopic imaging in difficult colonoscopy. BACKGROUND: Few endoscopy centers have easy access to fluoroscopy to facilitate difficult colonoscopy. Its benefits are therefore unclear. Although interest in colonoscope imaging has recently been stimulated by magnetic imaging techniques, these are expensive and unlikely to be widely available for some time. STUDY: During routine colonoscopy lists, a mobile fluoroscopy unit was used when colonoscopy could not be completed in the absence of stricturing despite changes in patient position and application of external pressure. This retrospective review assesses the percentage of procedures completed with and without fluoroscopy. RESULTS: A series of 1551 procedures in adult patients without colon resection and with satisfactory bowel preparation was analyzed. The cecal intubation rate was 95.1% (1475/1551), rising to 96.5% (1475/1528) when impassable strictures were excluded. Fluoroscopy was used in 61 (4%) of the 1528 procedures without stricture, but allowed completion in only 13% (8/61). In the absence of stricture, fluoroscopy improved completion rate by only 0.5% (from 96.0% to 96.5%). CONCLUSIONS: Fluoroscopy is seldom required and even then contributes little to success. Magnetic imaging, which provides continuous 3-dimensional images, may be more likely to speed and facilitate completion.

Adolescent↗
PubMed2004

Radiopacity of current endovascular stents: evaluation in a multiple reader phantom study.

PURPOSE: To evaluate the radiopacity of endovascular stents based on the fluoroscopy mode in a phantom of the human pelvis. MATERIALS AND METHODS: The following stents were included in this study: Medtronic AVE Bridge, Medtronic AVE Bridge X, Cordis Covered Nitinol (Covent), Guidant Dynalink, Luminexx, Guidant Megalink, Memotherm Flexx, Palmaz Medium, Palmaz-Schatz Long-Medium, Palmaz Corinthian PQ394Q and PQ294Q, SelfX, SMART without markers, SMART with radiopaque markers, Easy Wallstent. To evaluate radiopacity, images of the stents placed in four different positions (lumbosacral junction left and right, iliosacral joint left and right) of a pelvic phantom were taken at the following modes: spotfilm, continuous fluoroscopy, 15 pulses per second, 7.5 pulses per second, and 3 pulses per second. Images were presented at random to four independent readers and radiopacity scores were assessed: 0 = not visible, 1 = poor visibility, 2 = average visibility, 3 = good visibility, and 4 = very good visibility. RESULTS: The Covent stent had the highest overall radiopacity score (3.25), followed by the Luminexx (3.04) and the Medtronic AVE Bridge X (2.74) stents. At the spotfilm mode, the best visible stents were the Medtronic AVE Bridge X, the Covent and the Easy Wallstent stents and at the continuous fluoroscopy mode, the Covent, the Luminexx, and the Medtronic AVE Bridge X stents. Decreasing the fluoroscopy mode went hand in hand with a reduction of the radiopacity scores of all stents. At the standard fluoroscopy mode of 7.5 pulses per second, the Covent stent was seen well or very well in 96.9%, followed by the Luminexx (76.9%), and the Medtronic AVE Bridge X (41.25%) stents. CONCLUSIONS: Stent radiopacity directly depends on the fluoroscopy mode; if the pulse frequency decreased, detecting the stents became more difficult. Stent mass correlates with stent radiopacity (e.g., Cordis Covered Nitinol, Bridge X). Radiopaque markers may improve stent radiopacity dramatically (e.g., Luminexx vs Memotherm Flexx).

Blood Vessel Prosthesis Implantation↗