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PubMed2002

Defining the femoral axis on lateral knee fluoroscopy.

The methodological detail about determining the femoral axis on lateral fluoroscopic images of the knee is lacking. This paper reports on the use of the posterior border of the lower femoral diaphysis to represent the axis. This method is accurate, simple, reliable and can be used by researchers studying knee joint kinematics using dynamic video fluoroscopy. It is also useful in the outpatient clinic to assess the flexion/extension position of femoral components after knee arthroplasty.

Arthroplasty, Replacement, Knee↗
PubMed2001

CT fluoroscopy-guided intervention: marked reduction of scattered radiation dose to the physician's hand by use of a lead plate and an improved I-I device.

PURPOSE: To estimate the effects of a lead plate, three types of needle holders, tube current, and slice thickness on decreasing the radiation dose to the physician's hand during interventional procedures with computed tomographic (CT) fluoroscopic guidance. The needle holders (I-I devices), which were developed by the authors, maintained the distance between the physician's hand and the CT plane at 7 cm, 10 cm, and 15 cm, respectively. MATERIALS AND METHODS: The dose rate (mSv/tube current/CT fluoroscopy time) was measured in 55 cases, which were divided into six groups. In group A (n = 14), the current was 135 kV, there was a 5-mm slice thickness, and a 7-cm I-I device was used without the lead plate. Group B (n = 11) entailed a 120-kV current, a 5-mm slice thickness, and a 7-cm I-I device without the lead plate. Group C (n = 8) entailed a 120-kV current, 5-mm slice thickness, and 7-cm I-I device with the lead plate. Group D (n = 9) entailed a 120-kV current, 5-mm slice thickness, and 10-cm I-I device with the lead plate. Group E (n = 7) entailed a 120-kV current, 5-mm slice thickness, and 15-cm I-I device with the lead plate. Group F (n = 6) entailed a 120-kV current, 1-mm slice thickness and 10-cm I-I device with the lead plate. To compare the effects of tube voltage, lead plate use, slice collimation, and I-I devices, differences were compared between groups A and B, B and C, D and F, and among groups C, D, and E. RESULTS: The dose rates of groups A, B, C, D, E, and F were 126.3, 75.2, 17.8, 13.9, 2.8, and 4.1 mSv/mA/sec x 100,000, respectively. There were significant differences in dose rates between groups A and B (t-test, P =.037), B and C (Student t-test, P =.002), D and F (Mann-Whitney test, P =.011), and among groups C, D, and E (Kruskal-Wallis test, P =.016). CONCLUSION: The lead plate, the improved I-I devices, use of a 120 kV (vs 135 kV) current, and 1-mm (vs 5 mm) collimation were all useful in decreasing the dose rate.

Biopsy, Needle↗
PubMed1997

Assessment of respiration during video fluoroscopy of dysphagic patients.

RATIONALE AND OBJECTIVES: The authors evaluated the coordination of swallowing and respiration in dysphagic patients. MATERIALS AND METHODS: Video fluoroscopy and respirometry were performed simultaneously during 98 swallows in 33 patients (18 women, 15 men) with a median age of 70 years (interquartile range, 52-78 years). Pharyngeal transit time, deglutition apnea, and the ratio between the two (swallowing safety index) were calculated. Presence of a misdirected swallow (aspiration or penetration) was indicated. RESULTS: Pharyngeal transit time was not associated with deglutition apnea. Misdirected swallow was associated with a slightly prolonged pharyngeal transit time, a slightly shorter deglutition apnea, and a significantly lower swallowing safety index (1.8 [1.0-4.2] vs 4.5 [2.4-6.7]; P < .001) compared with normally directed swallow. The association between misdirected swallow and lower swallowing safety index was independent of pharyngeal transit time. CONCLUSION: Assessment of respiration is important in the evaluation of dysphagia. Aspiration, especially in elderly dysphagic patients, may be a consequence of primarily disturbed respiration. A low swallowing safety index may indicate risk of misdirected swallow.

Aged↗
PubMed2006

Successful localization and surgical removal of ingested sewing needles under mini C-arm fluoroscopy: a case report.

Foreign body ingestion is common, but ingestion of multiple sewing needles is rare. Most ingested sharp metallic bodies pass through the digestive tract spontaneously and patients can be managed conservatively. Sometimes, however, perforation develops and surgical treatment is necessary. It is hard to localize ingested sewing needles because they tend to scatter widely in the digestive tract and are impalpable manually. We report a psychiatric patient who ingested six sewing needles: one intact needle was found at the larynx, one had penetrated into the stomach, one was in the duodenum, one was in the cecum, one was broken into two pieces, and the final needle was broken into three pieces. All of the broken fragments were in the colon. The needle at the larynx was removed by a laryngoscope. Subsequently, we used mini C-arm fluoroscopy to localize the remaining needles and successfully removed all of them intraoperatively.

Aged↗
PubMed2002

Investigation of cervical patency and uterine appearance in domestic cats by fluoroscopy and scintigraphy.

The cervical patency of six domestic female cats was monitored under sedation by infusion of contrast medium (Omnipaque) into the cranial vagina during early oestrus, mid-oestrus, late oestrus and interoestrus or a radiopharmaceutical ((99m)Tc-HSA) during mid- and interoestrus in a non-ovulatory oestrous cycle. The transport of the contrast medium or the radiopharmaceutical through the cervix and within the uterine horns was observed under fluoroscopy and with the aid of scintigraphy. In three of the queens, transcervical transport of contrast medium was demonstrated in all stages of oestrus, in one queen during mid-oestrus, late oestrus and 1 day after oestrus, and in two queens only during late oestrus. The relations between the cervical patency to the contrast medium and the oestrous behaviour, cornification of the vaginal cells and the serum oestradiol-17beta concentration were evaluated, and a relationship was found between the cervical patency and the degree of vaginal cornification. Transcervical transport of the radiopharmaceutical was observed in three queens during mid-oestrus. When the cervix was open, hysterography under a fluoroscope and hysteroscintigraphy were performed. The fluoroscopic and scintigraphic recordings revealed the patterns of the uterine contractions during oestrus in both ascending and descending directions, and the movement of the uterine contents back and forth between the uterine horns. The hysterograms were classified according to the shape of the uterine horns and the appearance of the endometrial lining. Spiral-shaped uterine horns with a smooth inner contour were observed in two queens, and a corkscrew appearance with irregular filling defects in the uterine lumen was shown in two queens that had developed subclinical cystic endometrial hyperplasia. These findings demonstrated that fluids or particles deposited in the cranial vagina of the cat can be transported into the uterus during some stages of the oestrous cycle. The fluoroscopic and scintigraphic techniques developed in this study may be further modified to permit more detailed studies of uterine contractile patterns and sperm transport in the feline female reproductive tract. Hysterography proved useful to diagnose uterine disease. The information on cervical patency is of value also for the development of techniques for artificial insemination in this species, and should be studied also in the ovulatory cycle.

Animals↗
PubMed2002

CT fluoroscopy-assisted puncture of thoracic and abdominal masses: a randomized trial.

PURPOSE: We investigated the benefit of real-time guidance of interventional punctures by means of computed tomography fluoroscopy (CTF) compared with the conventional sequential acquisition guidance. MATERIAL AND METHODS: In a prospective randomized trial, 75 patients underwent either CTF-guided (group A, n = 50) or sequential CT-guided (group B, n = 25) punctures of thoracic (n = 29) or abdominal (n = 46) masses. CTF was performed on the CT machine (Somatom Plus 4 Power, Siemens Corp., Forchheim, Germany) equipped with the C.A.R.E. Vision application (tube voltage 120 kV, tube current 50 mA, rotational time 0.75 s, slice thickness 10 mm, 8 frames/s). RESULTS: The average procedure time showed a statistically significant difference between the two study groups (group A: 564 s, group B 795 s, P = 0.0032). The mean total mAs was 7089 mAs for the CTF and 4856 mAs for the sequential image-guided intervention, respectively. The sensitivity was 71% specificity 100% positive predictive value 100% and negative predictive value 60% for the CTF-guided puncture, and 68, 100, 100 and 50% for sequential CT, respectively. CONCLUSION: CTF guidance realizes a time-saving but increases the radiation exposure dosage.

Abdominal Neoplasms↗
PubMed2003

The use of intraoperative fluoroscopy to reduce femoral interference screw divergence during endoscopic anterior cruciate ligament reconstruction.

Femoral interference screw divergence can potentially have detrimental consequences in the rehabilitation of anterior cruciate ligament (ACL) reconstruction. Several biomechanical studies suggest that divergence angles greater than 15 degrees significantly decrease the pullout strength of the graft. Numerous techniques have been described in the literature that address this issue; however, the use of an image intensifier intraoperatively is not frequently discussed. We describe a technique in which fluoroscopy is used to confirm the proper position of the femoral interference screw at the time of the procedure, and therefore minimizes the incidence of significant screw divergence. Radiographic analysis of 62 patients who underwent endoscopic ACL reconstruction using bone-patellar tendon-bone autograft using this technique revealed significant divergence in only 3% of patients.

Anterior Cruciate Ligament↗
PubMed2000

[Examination of the image quality from digital fluoroscopy equipment with 1k- and 2k-image matrix].

PURPOSE: The image quality of 1k- and 2k-radiographs from digital fluoroscopy equipments (Sireskop SX and Polystar SX--Siemens) are characterized by comparison with each other to evaluate the relevance of this technique in clinical routine. MATERIAL AND METHODS: We examined fabricated and evaluated images with 1k- and 2k-image matrix from several high and low contrast phantoms and from skeleton phantoms. On the one hand, the digital image values can be used directly for the evaluation, on the other hand the comparing evaluation by experienced radiologists resulted from a visual consideration in a blind study. RESULTS: The quality difference of the 1k- and 2k-images depends mainly on the distance of the investigated sector of the object to the image intensifier and on the scattering of the radiation in the object positioned between the investigated sector and the image intensifier. The nearer the investigated object is located to the intensifier and the smaller the radiation is scattered in the object, the more the image quality of a radiograph with a 2k-matrix is increasing in comparison to an image with 1k-matrix. The higher the tube voltage, the smaller are the differences. CONCLUSION: The image quality enhancement because of the more sensitive sampling of the Saticon target in the 2k-matrix is limited by the opening of the iris positioned in the light distributor. Therefore the image quality differences of medical 1k- and 2k-radiographs in many cases are small.

Bone and Bones↗
PubMed2004

[Ultrasound- and fluoroscopy-guided implantation of peripherally inserted central venous catheters (PICCs)].

PURPOSE: Evaluation of ultrasound- and fluoroscopy-guided implantation of peripherally inserted central venous catheters (PICCs). MATERIALS AND METHODS: In 32 patients (12 males, 20 females; mean age 64.1 +/- 11.9 years) with clinical indication for long term central venous catheter (chemotherapy: N = 5; parenteral nutrition and fluid substitution: N = 26; parenteral pain therapy: N = 1) a PICC was placed by an interventional radiologist using ultrasound guidance. RESULTS: The placement of the PICC was technically successful in 31 (96.9%) patients, with placement of 20 single-lumen 5F PICCs, 4 double-lumen 6F PICCs and 7 double-lumen 7F PICCs. The mean duration of catheter usage was 28.4 (2 - 161) days with a total of 910 catheter days. No catheter occlusions were recorded. Two patients developed a superficial venous thrombosis of the upper extremity. The resulting thrombotic rate was 2.2 per 1000 catheter days. No catheter associated infection was recorded. CONCLUSION: The ultrasound guided placement of peripherally inserted central venous catheters (PICCs) via a superficial vein of the upper extremity is a practical alternative to central catheters via central veins.

Adult↗
PubMed1997

[Spiral CT for the detection of coronary artery calcifications and the prognosis of coronary heart disease--a comparison with fluoroscopy and coronary angiography].

PURPOSE: Evaluation of clinical relevance of coronary calcifications detected by helical CT. Evaluation of congruence with fluoroscopy (FS) and coronary angiography. Comparison with studies reporting on application of ultrafast computed tomography. MATERIALS AND METHODS: 40 patients underwent helical CT (2 mm slice thickness, table-feed 3 mm/s). Coronary angiography and FS were performed in usual technique. Stenosis and calcifications were evaluated semiquantitatively. RESULTS: 28 of 28 stenoses > or = 75% were detected via helical CT by evaluation of calcification (FS: 19). One non-detected solitary stenosis was calculated as 40%. FS did not detect 4 cases with 2-vessel and 3-vessel disease each one case with 1-vessel disease, and one case with a main stem stenosis. Sensitivity of helical CT was 97% (FS: 66%). For the evaluation of stenosis III degree (> or = 75%), sensitivity was 100% (FS: 58%), specificity was 77% (FS: 48%). CONCLUSION: Helical CT is more sensitive for haemodynamically relevant stenoses than FS. Helical CT is suitable as a substantial non-invasive diagnostic procedure in coronary heart disease. In certain cases, e.g. if the patient suffers from additional risks, helical CT should be done prior to coronary angiography. Coronary calcifications found incidentally in symptomatic patients at chest CT warrant further cardiological investigation.

Adult↗
PubMed2001

Real-time 3-dimensional echocardiography imaging for right ventricular endomyocardial biopsy: a comparison with fluoroscopy.

Real-time 3-dimensional (RT3D) echocardiography has the potential to precisely identify the position of an object in 3-dimensional space. Therefore, we hypothesized that RT3D echocardiography could rapidly facilitate accurate placement of a bioptome within the right ventricle and may offer advantages over a fluoroscopically guided approach. During 63 routine right ventricular biopsy procedures (total of 315 biopsy attempts) in 33 cardiac allograft recipients, the bioptome was initially guided against the intraventricular septum with the use of biplane fluoroscopy. Bioptome position was then evaluated by RT3D echocardiography by using the Volumetrics Model 1 with the transducer placed at the apex. Multiple long-axis and short-axis planes were simultaneously visualized and customized to identify the tip of the bioptome. Bioptome placement was prospectively classified as septal, free wall/septal junction, or free wall. Of the 36 patients studied, 33 (91%) had adequate RT3D images. Of 315 bioptome placements visualized by RT3D echocardiography after fluoroscopic placement, bioptome position against the septum was confirmed in 113 (36%), against the septal/free wall (anterior or posterior) junction in 140 (44%), against the free wall in 60 (19%), and in the coronary sinus in 2 (1%). RT3D echocardiography is readily feasible for use in the majority of transplant patients undergoing right ventricular endomyocardial biopsy. Visualization of the bioptome in multiple simultaneous planes allows accurate localization of the biopsy site. The potential for improved localization of the bioptome tip in the right ventricle may have important clinical implications for augmenting the efficacy of this procedure.

Adult↗
PubMed1998

CT-guided transthoracic fine-needle aspiration versus transbronchial fluoroscopy-guided needle aspiration in pulmonary nodules.

PURPOSE: To evaluate the diagnostic yield of CT-guided (CTNAB) and fluoroscopy-guided transbronchial (TBNA) fine-needle aspiration cytology in pulmonary nodules and to compare their complications. MATERIAL AND METHODS: Thirty patients with pulmonary nodules not abutting upon the chest wall and inaccessible to bronchoscopy were randomised for CTNAB or TBNA. Eighteen patients underwent CTNAB and 16 TBNA. Four patients underwent both procedures. RESULTS: In the CTNAB group, a definitive diagnosis could be made in 14 (78%) out of 18 patients whereas in the TBNA group, a definitive diagnosis was made in 11 (69%) out of 16 patients. This difference was not statistically significant (p > 0.05). The final diagnosis in 29 out of 30 patients comprised primary bronchogenic carcinoma in 14 patients, metastases in 5 patients, and benign lesions in 10 patients (34%) of which 3 lesions (30%) were of tuberculous aetiology. There were 2 asymptomatic pneumothoraces in the CTNAB group and no complication was observed in the TBNA group. CONCLUSION: Both techniques were safe and effective in the diagnosis of peripheral pulmonary lesions. TBNA was best suited for lesions larger than 3 cm and located in the middle and lower lobes while CTNAB could be used for any lesions.

Adult↗
PubMed2001

Transrectal catheter drainage of deep abdominal and pelvic abscesses using combined ultrasonography and fluoroscopy.

OBJECTIVE: To describe our experience with transrectal drainage of deep abdominal or pelvic abscesses guided by ultrasonography and fluoroscopy. DESIGN: Open study. SETTING: Teaching hospital, Sweden. SUBJECTS: Eight seriously ill patients with deep abdominal or pelvic abscesses. INTERVENTION: Ultrasonographic and fluoroscopic transrectal drainage. MAIN OUTCOME MEASURES: Clinical follow-up. RESULTS: Eight patients (2 septic, 2 with high fever, and 2 with moderate fever) were effectively and safely drained without general anaesthesia. Their condition improved considerably within hours after drainage. Three patients had recurrent abscesses as a result of the underlying disease. The drainage overcame the sepsis in two patients and allowed a later elective operation. CONCLUSIONS: Transrectal ultrasonographic and fluoroscopic drainage is an effective and safe method for treatment of deep abdominal or pelvic abscesses in seriously ill patients.

Abdominal Abscess↗
PubMed1983

Theoretical and experimental studies of the influence of air kerma rate on threshold contrast in diagnostic fluoroscopy systems.

Experimental measurements of threshold contrast (CT) as a function of air kerma rate at the input plane of the image intensifier have been made for several diagnostic fluoroscopy units in clinical use. Threshold contrasts are determined by viewing a test object containing holes of fixed diameter and various depths under defined irradiation conditions. Kerma rate variations are effected by introducing aluminum sheets into the x-ray beam at fixed values of tube potential and current. At low kerma rates where quantum noise dominates, low tube potentials (60 kVp) usually yield lower values of CT than do higher potentials (100 kVp). At higher kerma rates the opposite is often true. A simple theoretical model for noise propagation in fluoroscopic imaging systems using models of diagnostic x-ray spectra lends qualitative support to the experimental findings. The often-quoted suggested upper limit of 100 mu R s-1 (0.87 mu Gy s-1) at the input phosphor would seem to be justified under the test conditions since little improvement in CT is usually observed at higher kerma rates. However, application to clinical practice would ideally require the use of more realistic phantom studies.

Air↗
PubMed1986

Use of digital fluoroscopy as an on-line verification device in radiation therapy.

We have applied digital fluoroscopy technology to the radiation therapy environment, and developed a real-time fluorescent dosemeter (RFD). Our aim was to utilise this system as an on-line treatment verification device. We have found that the system behaves basically as a large array (512 X 512) of dosemeters. Using this device, instantaneous information about the actual treatment beam can be obtained simultaneously with the commencement of irradiation. As an array of dosemeters, it provides a detailed description of the dose distribution (exit dose) throughout the treatment. Furthermore, by applying image enhancement techniques to this measured information, good quality portal images are produced instantaneously and continuously during the entire irradiation for visual evaluation. The availability of this system should lead to improvements in precision in present dose delivery procedures.

Fluoroscopy↗
PubMed2004

Corticosteroid injections for trochanteric bursitis: is fluoroscopy necessary? A pilot study.

BACKGROUND: Numerous studies have demonstrated that therapeutic injections carried out to treat a variety of different pain conditions should ideally be performed under radiological guidance because of the propensity for blinded injections to be inaccurate. Although trochanteric bursa injections are commonly performed to treat hip pain, they have never been described using fluoroscopy. METHODS: The authors reviewed recorded data on 40 patients who underwent trochanteric bursa injections for hip pain with or without low back pain. The initial needle placement was done blindly, with all subsequent attempts done using fluoroscopic guidance. After bone contact, imaging was used to determine if the needle was positioned on the lateral edge of the greater trochanter (GT). Once this occurred, 1 ml of radiopaque contrast was injected to assess bursa spread. RESULTS: The GT was contacted in 78% of cases and a bursagram obtained in 45% of patients on the first needle placement. In 23% of patients a bursagram was obtained on the second attempt and in another 23% on the third attempt. Four patients (10%) required four or more needle placements before a bursagram was appreciated. Attending physicians obtained a bursagram on the first attempt 53% of the time vs 46% for fellows and 36% for residents (P=0.64). Older patients were more likely to require multiple injections than younger patients. CONCLUSIONS: Radiological confirmation of bursal spread is necessary to ensure that the injectate reaches the area of pathology during trochanteric bursa injections.

Adrenal Cortex Hormones↗
PubMed2004

Assessing bone mineral density in vivo: digitized fluoroscopy and ultrasound.

The genetic component of osteoporosis in caged laying hens is large, and a method for detecting hens susceptible to fracture could be useful in breeding programs. A radiographic absorptiometry film method was modified by video digitization from an image intensifier and computer analysis and termed digitized fluoroscopy (DF). Humeral and ulnar DF values were measured in 165 hens during lay. Relationships (P < 0.001) were seen between DF assessments from 25 wk onward and postmortem measurements at 70 wk. We conclude that DF can detect poor bones in hens early but is problematic. Quantitative ultrasound was also investigated. We measured amplitude-dependent speed-of-sound (Ad-SoS) in the third toe in hens. Nutritional studies revealed Ad-SoS values correlated with postmortem peripheral quantitative computerized tomography, (control group, r = 0.48, P < 0.001; treatment group, r = 0.39, P < 0.001). In caged and free-range hens, Ad-SoS correlated with shear strength (r = 0.33, P < 0.001, all hens) and radiographic density values (r = 0.53, P < 0.001, all hens) measured postmortem. The Ad-SoS values were higher in free-range than in caged hens (1,904 vs. 1,850 m/s, P < 0.001). Ad-SoS measurements were made in hens from a study where divergent genetic selection has produced high and low bone index lines with 92% difference in tibia strength. The value in high bone index hens was higher than in low bone index hens at 32 (P < 0.001), 42 (P < 0.001), 52 (P < 0.05), and 62 wk (P < 0.001) in generation 8. In an Ad-SoS heritability study, heritability estimates ranged from 0.15 to 0.39. We conclude that Ad-SoS is a heritable trait, reflects other bone measurements, and rapidly detects poor bone quality in hens.

Animals↗
PubMed2006

Subjective and objective measures of image quality in digital fluoroscopy.

There are numerous methods for assessing image quality in diagnostic X ray. In our study we assessed how imaging quality assurance methods perform in practice. Physics assessments were based on IPEM protocols using Leeds test objects. Clinical assessment was based on a questionnaire. A total of 15 systems in three European locations were assessed, covering a range of image intensifier-TV digital fluoroscopy units. Analysis of 274 clinical questionnaires showed that clinical and physics assessments did not place systems in the same order, based on a given image quality parameter. In almost all the comparisons, low level correlation was measured for statistical comparison of rank order (rs < 0.3). However, broad agreement was observed between physics and clinical assessments for image quality associated with contrast and noise. This study emphasises the importance of maintaining links with clinical assessment, when developing quality assurance metrics, and measuring the mutual performance of clinical and physical assessments of image quality.

Europe↗