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Post-lymphographic percutaneous fine needle biopsy of lymph nodes guided by fluoroscopy.

Fine needle, percutaneous aspiration of suspect lymph nodes was carried out in 29 patients during fluoroscopy. The correct positioning of the needle was assured if the node moved with the tip of the needle. In 29 patients, there were 65 successful aspirations and 29 failures. Anesthesia is recommended but care should be taken that the anesthetic does not reach the lymph node itself as this can cause distortion of the cells.

Biopsy, Needle↗

A hybrid computerized fluoroscopy technique for noninvasive cardiovascular imaging.

The excellent linearity of digital image storage and retrieval permits hybrid analog-digital subtraction to extend the spatial resolution of two previously developed algorithms which employed entirely digital apparatus. A low resolution, time-integrated preinjection digital mask image is reconverted to analog form and subtracted from live analog video images of iodine administered by peripheral intravenous injection to produce a high resolution display of the cardiovascular system with contrast ten times greater than conventional fluoroscopy. Preliminary studies in dogs are compared with images obtained with our digital subtraction algorithms.

Animals↗

Routine fluoroscopy using minispot cameras.

Routine fluoroscopy was performed using 100- and 105-mm spot film cameras. Radiation dose was reduced to between 30% and 43%, and cameras were acceptably reliable. Cost for film and holders was high.

Fluoroscopy↗

Imaging-guided injection techniques with fluoroscopy and CT for spinal pain management.

Local spinal pain and radiculopathy are common conditions that debilitate millions of Americans annually. Most cases are successfully treated conservatively with rest or physical therapy. Chiropractic manipulation or, in some cases, surgery may also be performed. Percutaneous injection has been used for spinal pain management for many years, but many of these procedures have historically been performed without imaging guidance. Recently, however, newer minimally invasive, imaging-guided percutaneous techniques have been added to the list of available treatment options for spinal pain. Imaging-guided techniques with fluoroscopy or computed tomography increase the precision of these procedures and help confirm needle placement. Cervical, thoracic, lumbosacral, and sacroiliac pain can be evaluated and treated safely and effectively with injections of local anesthetics or long-acting steroids into facet joints, sacroiliac joints, selective nerve roots, spondylolytic areas, and the epidural space. Because imaging-guided techniques appear to provide better results and reduce complication rates, they are becoming more popular despite controversy regarding their effectiveness. Controversy will continue to surround these imaging-guided techniques until large, double-blinded studies become available. In the meantime, there is an increased demand for these procedures from referring physicians, and it is important to be able to safely perform them with a minimum of patient discomfort.

Anesthetics, Local↗

Radiography and fluoroscopy, 1920 to the present.

A survey of radiological procedures carried out in 1980 by J. L. Johnson and D. L. Abernathy indicated that of the 181 million procedures performed in that year, there were 77.5% plain radiographic studies, 12.7% contrast studies, 4.0% sonographic studies, 3.2% nuclear medicine studies, 1.8% CT studies and 0.8% special vascular procedures and cardiac catheterizations. Note that over 90% of all the studies were of the "conventional" type and that fewer than 2% were CT studies. In the early 70's when CT was introduced, it was predicted that it would soon take over most of radiography; some 7 or 8 years later, it was obvious that this would not take place. According to Tanako of the Fuji Photo Film Co. Ltd., conventional radiography has resisted being pushed aside because of its very high information content: 4-6 megabytes per image. A CT image contains about 0.5 megabytes. If a system is to take over from conventional radiography, it will have to overcome this large difference in information content. Digital or computed radiography seems capable of this, but probably not for some time (perhaps, 10 or 20 years). It seems unlikely that there will be much change, except for refinement, in the image intensified fluoroscopy equipment used for observing dynamic processes, and it will probably not be replaced. Another situation which will preclude the rapid demise of conventional radiography is financial inertia: There is between 5 and 10 billion dollars worth of diagnostic equipment in hospitals in this country and significant amount more in private offices and clinics. It is true that the amount has diminished in recent years, but this has been more because of DRG's than because of "takeover" by new modes of imaging. It is not likely that this investment will be given up quickly or easily. One must also keep in mind that the film digitization and the photostimulable phosphor digital systems, described above, do use existing radiographic equipment, and the image intensification system uses a great portion of existing fluoroscopic equipment, therefore "going digital" may not require complete replacement of existing equipment.

Fluoroscopy↗

Robotically driven interventions: a method of using CT fluoroscopy without radiation exposure to the physician.

Radiation exposure to physicians' hands during interventional procedures with computed tomography (CT) fluoroscopic guidance may be high. A robot was developed that could hold, orient, and advance a needle, with CT fluoroscopic guidance. This robot could be either computer or joystick controlled. Twenty-three robotically guided percutaneous interventions were performed without complication. Physician radiation exposure was negligible during the CT fluoroscopy-guided procedures.

Aged↗

Patient-specific region-of-interest fluoroscopy device for X-ray dose reduction.

A region-of-interest (ROI) fluoroscopy device that provides an automatically generated ROI filter with an arbitrary shape, as well as digitally compensated images, was built and evaluated. ROI filters were generated by using a deformable attenuation material. Images were compensated by using a compensation ratio and a running average interpolation method. Image compensation parameters were predicted on the basis of the x-ray tube potential used. The image quality with and without an ROI filter was evaluated. This ROI fluoroscopic technique was shown to substantially reduce patient and operator radiation exposure without degrading image quality within the ROI.

Filtration↗

Placement of peripherally inserted central catheters without fluoroscopy in children: initial catheter tip position.

PURPOSE: To determine how often placement of peripherally inserted central catheters (PICCs) without imaging guidance results in an initially correct central venous catheter tip location. MATERIALS AND METHODS: This study was approved by the hospital's institutional review board, which waived the requirement for informed consent. In a children's hospital, 843 PICCs were placed in 698 patients (age range, 0 days to 26 years; mean, 6.9 years) during a 14-month study period. All PICCs were placed by a specialized team of PICC nurses and interventional radiology technologists in an angiography suite with the supervision of pediatric interventional radiologists. All catheters were threaded blindly to a previously estimated length by either a PICC nurse or a pediatric interventional radiologist, according to National Association of Vascular Access Networks guidelines, and the initial PICC tip location was then determined by means of spot fluoroscopy. PICC tips were regarded as central if they resided anywhere within the superior vena cava (SVC). All catheters were then manipulated with intermittent fluoroscopic guidance to achieve a final central position in the distal third of the SVC. A chi2 test was used to compare initial and final PICC tip locations according to patient age, catheter size, accessed vein, and need for radiologist assistance. A t test was used to compare procedure time with and without radiologist assistance. RESULTS: Analysis included 843 consecutively placed pediatric PICCs, of which 723 (85.8%) had a noncentral initial PICC tip position and required additional manipulation. After catheter repositioning performed with intermittent fluoroscopic guidance, a final central PICC tip location was achieved in 760 PICCs (90.2%). CONCLUSION: Pediatric PICC placement without fluoroscopic guidance required catheter manipulation of initial PICC tip position in 723 cases (85.8%). PICC placement with fluoroscopic guidance is highly successful, and the authors believe it is best performed in an angiography suite.

Adolescent↗

Real-time digitally subtracted fluoroscopy for cervical myelography.

Improved visualization of the initial bolus of contrast material injected via a lateral Cl-2 puncture for cervical myelography can be obtained by using real-time digital subtraction fluoroscopy. As little as 0.1 ml of metrizamide (250 mg%) can be demonstrated easily.

Fluoroscopy↗

Ureteral calculi: percutaneous removal using modified basket extractors and fluoroscopy.

Two modified helical basket extractors are described that have increased the success rate of removing ureteral calculi using fluoroscopy from 63% to 92%. Initially a rather stiff and expandable basket with a 20-cm filiform tip is used with coaxial catheters and sheath (stage 1). If this procedure is unsuccessful, a basket with two long cable ends is passed from the nephrostomy out through the urethra (stage 2). When used with coaxial bladder catheters, this technique allows dilatation of the vesicoureteric junction and retrograde catheterization and injection of fluids or gas to dislodge the stone prior to extraction. In a series of 38 patients, stones were removed in all but three (a success rate of 92%). In five cases small stones (less than 5 mm) were not retrieved but subsequent studies were normal. Ureteral stones were found in the abdominal ureter in 28 cases, in the pelvic ureter in seven cases, and in multiple sites in three cases. Stones were larger than 1 cm in 27.7% of cases. Postextraction mucosal edema with reduced ureteral patency was common but usually cleared in 2-3 days. Occasional complications were related to the nephrostomy.

Fluoroscopy↗

Manual compression device for fluoroscopy.

A device for manual compression and palpation during supine fluoroscopy has been designed. It enables effective use of the physiologic grasping and lever force potentials of the hand and wrist. The device permits optimal fluoroscopic palpation and compression techniques and prevents direct exposure to the lead-gloved hand.

Fluoroscopy↗

MR fluoroscopy: initial clinical studies.

Magnetic resonance (MR) fluoroscopy is a method for high-speed MR image acquisition with the goals of short acquisition time per image (500 msec or less), high image rate (10 images or more per second), and high-speed image reconstruction (150 msec or less from data acquisition to image display). The authors present their results with the first two goals in volunteers. MR fluoroscopic image data were acquired with a limited flip angle pulse sequence with reduced repetition times (TRs) and fewer phase encodings used per image. The sequence was applied continuously, and images were formed by updating one set of data with data from the most recently taken measurements. Sample head images were generated with TR/echo times as small as 11/5.5 msec and 48 phase encodings for a total acquisition time of about 500 msec. Images were acquired while the volunteer flexed his head. Artifacts from the motion became less evident on images as progressively shorter acquisition times were used.

Brain↗

Intraoperative cholangiography: use of portable fluoroscopy and transmitted images.

Intraoperative cholangiograms were obtained with portable fluoroscopy in 53 patients during laparoscopic cholecystectomy, and the images were transmitted to the radiology department. Each image was assessed for diagnostic quality and bile duct abnormalities (eg, retained stones and duct aberrancies). The aberrancy rate was 5.7% with the aberrant duct in the region of surgical dissection. The fluoroscopic technique provided diagnostic images with the advantage of real-time visualization, immediate communication with the surgeon, and the potential to decrease the risk of bile duct injury.

Cholangiography↗

Fluoroscopy-guided sacroiliac joint injections.

The authors performed fluoroscopy-guided sacroiliac (SI) joint injections. With the patient prone and the x-ray tube perpendicular to the fluoroscopic table, the skin was marked over the distal 1 cm of the SI joint. With the tube angled 20 degrees - 25 degrees cephalad, a 22-gauge needle was inserted at the skin mark and advanced perpendicular to the fluoroscopic table toward the posterior joint. Nonionic contrast material was injected to confirm the intraarticular position of the needle. Of 31 SI joint injections, 30 (97%) were intraarticular. Mean procedure time was 108 seconds. This technique is safe, rapid, and reproducible.

Adult↗

Gynecologic brachytherapy: digital fluoroscopy for placement verification and treatment planning.

The authors evaluated the feasibility of using digital fluoroscopic images for device placement verification and dosimetric planning for gynecologic brachytherapy. Adequate images were obtained rapidly, and the limited pincushion distortion on digital fluoroscopic images produced negligible variations in brachytherapy dose calculations compared with those calculated with standard radiographs. Intraoperative digital fluoroscopy can facilitate both placement verification and dosimetric planning for gynecologic brachytherapy.

Brachytherapy↗

Validation of a novel luminal flow velocimeter with video fluoroscopy and manometry in the human esophagus.

There is currently no ideal method for concurrently assessing intraluminal pressures and flows in humans with high temporal resolution. We have developed and assessed the performance of a novel fiber-optic laser-Doppler velocimeter, mounted in a multichannel manometric assembly. Velocimeter recordings were compared with concurrent fluoroscopy and manometry following 50 barium swallows in healthy subjects. During these swallows, the velocimeter sensor was situated in either the proximal (24 swallows) or the distal (26 swallows) esophagus. It signaled intraluminal flow following 46 of 50 swallows. A greater mean number of deflections were recorded in the distal compared with the proximal esophagus (4. 3 vs. 2.4, P = 0.001). The maximal flow velocity recorded did not differ between the proximal and distal esophagus (76.7 vs. 73.8 mm/s). No velocimeter signals commenced after fluoroscopic lumen occlusion. The velocimeter signals were closely temporally related to fluoroscopic barium flow. Upward catheter movement on swallowing sometimes appeared to cause a velocimeter signal. Manometrically "normal" swallows were no different from "abnormal" swallows in the number and velocity of deflections recorded by the velocimeter. This novel instrument measures intraluminal flow velocity and pressures concurrently, thus enabling direct study of pressure-flow relationships. Flow patterns differed between the proximal and distal esophagus.

Adult↗

Diaphragmatic displacement measured by fluoroscopy and derived by Respitrace.

In eight healthy volunteers we simultaneously measured the axial diaphragmatic motion by fluoroscopy and the cross-sectional area changes of the rib cage (RC) and abdomen (ABD) by Respitrace (RIP) during semistatic vital capacities (VC). We found that, if the fluoroscopic axial displacement of the posterior part of the diaphragm between residual volume (RV) and total lung capacity (TLC) is considered equal to 100%, the movement of the middle part is 90%, whereas that of the anterior part is only approximately 60%; the ratio of the axial displacements to mouth volume, furthermore, decreases at high lung volumes, especially for the anterior part. The RIP signal is nearly linearly related to mouth volume, but the contribution of the RC (delta RC) progressively increases (and is approximately 80% RIP at TLC), whereas the volume contribution of the ABD (delta ABD) levels off (to 20% RIP at TLC). The diaphragmatic volume displacement calculated from the theoretical analysis described by Mead and Loring also levels off at high volumes similarly as the ABD but is approximately 50% RIP at TLC. Finally, the axial movements of the three parts of the diaphragm are linearly related to the RC and ABD cross-sectional-area changes (r 0.91-0.97) and are even significantly better correlated with the "calculated" diaphragmatic volume displacement.

Adult↗

Early experience with real-time CT-fluoroscopy for an intracranial lesion.

We have developed a real-time CT-fluoroscopy (CTF) system of which the initial trial was reported in 1993. This paper deals with the early clinical experience with this system. A third-generation scanner equipped with a slip-ring (Toshiba) was used. Images were reconstructed and displayed at a rate of 6/s with a 0.83-second delay time using a newly designed array processor. CTF was carried out in 12 cases (10 brain hemorrhages, 2 tumors). Good-quality fluoroscopic images were obtained in all cases. Real-time monitoring with CTF of needle placement and advancement was useful for accurate puncture needle biopsy and evacuation of the lesions. No serious complication was experienced in this series.

Biopsy, Needle↗