Study design: Equivalence trial (IRB not required for cadaveric studies).
Objective: To compare computer-guided and fluoroscopic kyphoplasty. Factors of interest were radiation exposure, position of cannula within pedicles and procedure time.
Methods: Kyphoplasty was performed on two cadavers. Computer-navigated, cross-sectional images from a cone-beam CT were used for one and fluoroscopic imaging for the other. In each, T6–9 and T11–L2 vertebrae were selected. For both imaging methods, anteroposterior and lateral x-rays were taken. Radiation exposure for both procedures was measured by four dosimeters. Procedure time, radiation to surgeon and cadaver, and position of cannula placement within pedicles were recorded. The surgeon wore one under the lead gown, another on the lead gown at shoulder level, and a third as a ring on the dominant hand. A dosimeter was also placed on the cadaver.
Results: The radiation from the cone-beam, computer-guided imaging system was 0.0 mrem to the surgeon and 0.52 rads to the cadaver. Using fluoroscopic imaging, surgeon's and cadaver's exposure was 5 mrem and 0.047 rads, respectively. Procedure times were similar and neither device resulted in cannula malposition.
Conclusions: Cone-beam CT appears as accurate as the fluoroscopy; radiation exposure to the surgeon is eliminated, and radiation levels to the patient are acceptable.
Percutaneous vertebroplasty (PV) requires relatively lengthy fluoroscopic guidance, which might lead to substantial radiation exposure to patients or operators. The two-fluoroscopic technique (two-plane radiographs obtained using two fluoroscopes) during PV can provide simultaneous two-planar projections with reducing operative time. However, the two-fluoroscopic technique may expose the operator or patient to increased radiation dose. The aim of this study was to quantify the amount of radiation exposure to the patient or operator that occurs during PV using one- vs. two-fluoroscopic technique.
Two radiation dosimeters were placed on the right flank of each patient and on the upper sternum of each operator during 26 single-level PV procedures by one senior surgeon. The use of two-fluoroscopic technique (13 patients) and one-fluoroscopic technique (13 patients) were allocated in a consecutive and alternative manner. The operative time and mean radiation dose to each patient and operator were monitored and compared between groups.
Mean radiation dose to the patient was 1.97 ± 1.20 mSv (95% CI, 0.71 to 3.23) for the one-fluoroscopic technique group vs. 0.95 ± 0.34 mSv (95% CI, 0.85 to 1.23) for the two-fluoroscopic technique group (P =0.031). Mean radiation dose to the operator was 0.27 ± 0.12 mSv (95% CI, 0.17–0.56) for the one-fluoroscopic technique group vs. 0.25 ± 0.14 mSv (95% CI, 0.06–0.44) for the two-fluoroscopic technique group (P = 0.653). The operative time was significantly different between groups: 47.15 ± 13.48 min (range, 20–75) for the one-fluoroscopic technique group vs. 36.62 ± 8.42 min (range, 21–50) for the two-fluoroscopic technique group (P =0.019).
Compared to the one-fluoroscopic technique, the two-fluoroscopic technique used during PV provides not only shorter operative times but also reduces the radiation exposure to the patient. There was no significant difference between the two techniques with regards to radiation exposure to the operator.
Vertebral compression fracture; Osteoporosis; Vertebroplasty; Radiation dose
BACKGROUND--Exposure to radiation is a hazard of invasive cardiology. To minimise the risk it is essential to keep the doses received as low as possible. AIM--To assess the effect on cardiologist radiation exposure and the quality of coronary artery opacification of the use of a remotely controlled mechanical pump for coronary arteriography. A secondary aim was to assess any disadvantages and safety. METHODS--319 patients were randomised to have coronary arteriography carried out with contrast injected either by hand or by a remotely controlled mechanical pump. Six cardiologists participated: two catheter laboratories were used and both brachial and femoral approaches were included. The exposure of the cardiologists to radiation was assessed by film badge dosimetry. The badges were worn on the hat. The total time for the procedure, screening time, the dose-area product meter reading, and any complications were recorded for each examination. The quality of arterial opacification was reported on a scale of 0-5. RESULTS--The mean radiation dose per procedure was 0.011 mSv for hand injection of contrast and 0.005 mSv for mechanical injection (p < 0.01). There were no differences in procedure times or screening times. There were no complications attributable to mechanical injection. Arterial opacification was not significantly different in the two groups (4.01 v 4.03 for the left coronary artery, 4.68 v 4.78 for the right coronary artery). The right coronary artery was consistently better opacified than the left by both techniques (4.59 v 3.89, p < 0.001). CONCLUSIONS--Use of a remotely controlled mechanical pump for coronary arteriography reduced cardiologist radiation exposure by half. It was not associated with any inconvenience, expense, or complications and produced arterial opacification at least as good as injection by hand.
Minimally invasive percutaneous pedicle screw instrumentation methods may increase the need for intraoperative fluoroscopy, resulting in excessive radiation exposure for the patient, surgeon, and support staff. Electromagnetic field (EMF)-based navigation may aid more accurate placement of percutaneous pedicle screws while reducing fluoroscopic exposure. We compared the accuracy, time of insertion, and radiation exposure of EMF with traditional fluoroscopic percutaneous pedicle screw placement.
Minimally invasive pedicle screw placement in T8 to S1 pedicles of eight fresh-frozen human cadaveric torsos was guided with EMF or standard fluoroscopy. Set-up, insertion, and fluoroscopic times and radiation exposure and accuracy (measured with post-procedural computed tomography) were analyzed in each group.
Sixty-two pedicle screws were placed under fluoroscopic guidance and 60 under EMF guidance. Ideal trajectories were achieved more frequently with EMF over all segments (62.7% vs. 40%; p = 0.01). Greatest EMF accuracy was achieved in the lumbar spine, with significant improvements in both ideal trajectory and reduction of pedicle breaches over fluoroscopically guided placement (64.9% vs. 40%, p = 0.03, and 16.2% vs. 42.5%, p = 0.01, respectively). Fluoroscopy time was reduced 77% with the use of EMF (22 s vs. 5 s per level; p < 0.0001) over all spinal segments. Radiation exposure at the hand and body was reduced 60% (p = 0.058) and 32% (p = 0.073), respectively. Time for insertion did not vary between the two techniques.
Minimally invasive pedicle screw placement with the aid of EMF image guidance reduces fluoroscopy time and increases placement accuracy when compared with traditional fluoroscopic guidance while adding no additional time to the procedure.
Minimally invasive; Electromagnetic field navigation; Pedicle screw; Fluoroscopy; Accuracy
Fluoroscopy has been an integral part of modern interventional pain management. Yet fluoroscopy can be associated with risks for the patients and clinicians unless it is managed with appropriate understanding, skill and vigilance. Therefore, this study was designed to determine the amount of radiation received by a primary operator and an assistant during interventional pain procedures that involve the use of fluoroscopy
In order to examine the amount of radiation, the physicians were monitored by having them wear three thermoluminescent badges during each single procedure, with one under a lead apron, one under the apron collar and one on the leg during each single procedure. The data obtained from each thermoluminescent badge was reviewed from September 2008 to November 2008 and the annual radiation exposure was subsequently calculated.
A total of 505 interventional procedures were performed with C-arm fluoroscopy during three months. The results of this study revealed that the annual radiation exposure was relatively low for both the operator and assistant.
With proper precautions, the use of fluoroscopy during interventional pain procedures is a safe practice.
fluoroscopy; interventional pain management; radiation exposure
Kyphoplasty (KP) is a minimally invasive technique for the percutaneous stabilisation of vertebral fractures. As such, this technique is highly dependent upon intraoperative fluoroscopic visualisation. In order to assess the range of radiation doses that patients are typically subjected to, 60 consecutive procedures using simultaneous bilateral fluoroscopy were analysed with respect to exposure time (ET). In a subset of 16 of these patients, a theoretical entrance skin dose (ESD) and effective dose was additionally calculated from intraoperatively measured dose area product. Average fluoroscopy time for single level cases reached 2.2 min (range 0.6–4.3) in the lateral plane and 1.6 min (range 0.5–3.0) in the anterior–posterior plane. For multiple level cases the corresponding ET per level was 1.7 min (range 0.6–2.9) per level in the lateral and 1.1 min (range 0.5–2.0) in the anterior-posterior plane. ESD was estimated as an average 0.32 Gy (range 0.05–0.86) in the anterior–posterior and 0.68 Gy (range 0.10–1.43) in the lateral plane. Effective dose (cumulative from both planes) averaged 4.28 mSv (range 0.47–10.14). Safety margins for the development of early transient erythema are respected within the presented fluoroscopy times. Longer ET in the lateral plane may however breach the 2 Gy threshold. Use of large c-arms and judiciously operating the exposure is recommended. With regard to effective dose, a single fluoroscopy guided KP performed for osteoporotic or traumatic vertebral fractures is a safe procedure.
Kyphoplasty; Patient radiation exposure; Biplanar fluoroscopy; Spine
Although many clinicians know about the reducing effects of the pulsed and low-dose modes for fluoroscopic radiation when performing interventional procedures, few studies have quantified the reduction of radiation-absorbed doses (RADs). The aim of this study is to compare how much the RADs from a fluoroscopy are reduced according to the C-arm fluoroscopic modes used.
We measured the RADs in the C-arm fluoroscopic modes including 'conventional mode', 'pulsed mode', 'low-dose mode', and 'pulsed + low-dose mode'. Clinical imaging conditions were simulated using a lead apron instead of a patient. According to each mode, one experimenter radiographed the lead apron, which was on the table, consecutively 5 times on the AP views. We regarded this as one set and a total of 10 sets were done according to each mode. Cumulative exposure time, RADs, peak X-ray energy, and current, which were viewed on the monitor, were recorded.
Pulsed, low-dose, and pulsed + low-dose modes showed significantly decreased RADs by 32%, 57%, and 83% compared to the conventional mode. The mean cumulative exposure time was significantly lower in the pulsed and pulsed + low-dose modes than in the conventional mode. All modes had pretty much the same peak X-ray energy. The mean current was significantly lower in the low-dose and pulsed + low-dose modes than in the conventional mode.
The use of the pulsed and low-dose modes together significantly reduced the RADs compared to the conventional mode. Therefore, the proper use of the fluoroscopy and its C-arm modes will reduce the radiation exposure of patients and clinicians.
fluoroscopy; radiation; radiation dosage; radiographic image enhancement
Over the years, there has been a tremendous increase in the use of fluoroscopy in orthopaedics. The risk of contracting cancer is significantly higher for an orthopedic surgeon. Hip and spine surgeries account for 99% of the total radiation dose. The amount of radiation to patients and operating surgeon depends on the position of the patient and the type of protection used during the surgery. A retrospective study to assess the influence of the radiation exposure of the operating surgeon during fluoroscopically assisted fixation of fractures of neck of femur (dynamic hip screw) and ankle (Weber B) was performed at a district general hospital in the United Kingdom.
Materials and Methods:
Sixty patients with undisplaced intertrochanteric fracture were included in the hip group, and 60 patients with isolated fracture of lateral malleolus without communition were included in the ankle group. The hip and ankle groups were further divided into subgroups of 20 patients each depending on the operative experience of the operating surgeon. All patients had fluoroscopically assisted fixation of fracture by the same approach and technique. The radiation dose and screening time of each group were recorded and analyzed.
The radiation dose and screening time during fluoroscopically assisted fixation of fracture neck of femur were significantly high with surgeons and trainees with less than 3 years of surgical experience in comparison with surgeons with more than 10 years of experience. The radiation dose and screening time during fluoroscopically assisted fixation of Weber B fracture of ankle were relatively independent of operating surgeon's surgical experience.
The experience of operating surgeon is one of the important factors affecting screening time and radiation dose during fluoroscopically assisted fixation of fracture neck of femur. The use of snapshot pulsed fluoroscopy and involvement of senior surgeons could significantly reduce the radiation dose and screening time.
Experience; fixation; fracture; radiation; surgeon
Background: Endoscopic retrograde cholangiopancreatography (ERCP) relies on the use of ionising radiation but risks to operator and patient associated with radiation exposure are unclear. The aim of this prospective study was to estimate the radiation dose received by personnel performing fluoroscopic endoscopic procedures, mainly ERCP.
Methods: Consecutive procedures over a two month period were included. The use of thermoluminescent dosimeters to measure radiation exposure to the abdomen, thyroid gland, and hands of the operator permitted an estimation of the annual whole body effective dose equivalent.
Results: During the study period 66 procedures (61 ERCP) were performed and the estimated annual whole body effective dose equivalent received by consultant operators ranged between 3.35 and 5.87 mSv. These values are similar to those received by patients undergoing barium studies and equate to an estimated additional lifetime fatal cancer risk between 1 in 7000 and 1 in 3500. While within legal safety limits for radiation exposure to personnel, these doses are higher than values deemed acceptable for the general public.
Conclusions: It is suggested that personnel as well as patients may be exposed to significant values of radiation during ERCP. The study emphasises the need to carefully assess the indication for, and to use measures that minimise radiation exposure during any fluoroscopic procedure.
The purpose of the study was to quantify patient exposure to ionising radiation during fluoroscopic-assisted arthroscopic surgery of the hip, establish a risk profile of this exposure, and reassure patients of radiation safety during the procedure.
We retrospectively analysed the dose area products for 50 consecutive patients undergoing arthroscopic hip surgery by an experienced hip arthroscopic surgeon. The effective dose and organ dose were derived using a Monte Carlo program.
The mean total fluoroscopy time was 1.10 minutes and the mean dose area product value was 297.2 cGycm2. We calculated the entrance skin dose to be 52 mGy to the area where the beam was targeted (81 cm2). The mean effective dose for intra-operative fluoroscopy was 0.33 mSv, with a SD of 0.90 Sv.
This study confirms that fluoroscopic-assisted arthroscopic surgery of the hip is safe with a low maximum radiation dose and supports its continued use in preference to alternative imaging modalities.
The aim of the present study was to determine whether there is a linear relation between the doses measured above and those measured under the lead apron of the radiologists performing interventional procedures. To monitor radiation exposure the International Commission of Radiological Protection (ICRP) recommends the use of a single dosimeter under the protective apron. To determine the exposure more accurately an additional dosimeter is recommended above the protective apron. The exposure of eight radiologists was monitored with two personal dosimeters during 3 consecutive years. To measure the doses uniformly the two dosimeters were worn in a special holder attached to the lead apron. The two personal dosimeters were replaced every 4 weeks on the same day. The doses above and under the protective aprons of seven radiologists did not differ significantly. A significant lower dose above and under the protective apron was measured for one of the radiologists. During a 4-week period the average dose measured above the lead apron was 3.44 mSv (median, 3.05 mSv), while that under the 0.25-mm lead apron was 0.12 mSv (median, 0.1 mSv). The coefficients of the regression line result in the equation Y = 0.036X − 0.004, with Y as the dose under the lead apron and X as the dose above the lead apron. The statistical analysis of the data established a linear relation between the doses above and those under the lead apron (R2 = 0.59). Before the special holder was introduced it was not possible to derive a relation between the doses above and those under the lead apron, as the doses were measured at varying places above and under the lead apron. There is no evidence that the effective dose can be estimated more accurately when an additional dosimeter is used. The present study revealed a threshold before doses under the lead apron were measured. Due to the threshold it can be concluded that the doses under the lead apron will not be underestimated easily when doses above the lead apron are used to calculate them. This is not the case when the doses above the lead apron are calculated for the doses under the lead apron.
Dosimetry; Fluoroscopy; Radiation protection; Effective dose; Lead apron
This study assessed the radiation safety at Nuclear Medicine Department being a work environment. Ionizing radiation exposure of the employees in the last 19 years and the effects of legislative changes in radiological protection were analyzed.
All employees of the investigated department were regularly and individually monitored using chest badges equipped with Kodak film type 2. Overall, 629 annual doses of the employees of nuclear medicine department, registered in the period 1991–2009, were analyzed statistically.
Technicians were found to be the largest exposed professional group, whereas nurses received the highest annual doses. Physicians received an average annual dose at the border detection methods. Ancillary and administration staff occasionally received doses above the method detection limit (MDL). The average annual dose for all dosimetry records was 0.7 mSv, and that for dosimetry records equal and higher than MDL was 2.2 mSv.
There was no case of an exceeded dose limit for a worker. Furthermore, improvement of radiological protection had a significant impact on the reduction of doses for the most exposed employees.
average annual effective dose; ionizing radiation exposure; radiation safety
Background Intramedullary nailing under fluoroscopic guidance is a common operation. We studied the intraoperative radiation dose received by both the patient and the personnel.
Patients and methods 25 intramedullary nailing procedures of the tibia were studied. All patients suffered from tibial fractures and were treated using the Grosse-Kempf intramedullary nail, with free-hand technique for fixation of the distal screws, under fluoroscopic guidance. The exposure, at selected positions, was recorded using an ion chamber, while the dose area product (DAP) was measured with a DAP meter, attached to the tube head. Thermoluminescent dosimeters (TLDs) were used to derive the occupational dose to the personnel, and also to monitor the surface dose on the gonads of some of the patients.
Results The mean operation time was 101 (48–240) min, with a mean fluoroscopic time of 72 seconds and a mean DAP value of 75 cGy·cm2. The surface dose to the gonads of the patients was less than 8.8 mGy during any procedure, and thus cannot be considered to be a contraindication for the use of this technique. Occupational dose differed substantially between members of the operating personnel, the maximum dose recorded being to the operator of the fluoroscopic equipment (0.11 mSv).
Interpretation Our findings underscore the care required by the primary operator not to exceed the dose constraint of 10 mSv per year. The rest of the operating personnel, although they do not receive very high doses, should focus on the dose optimization of the technique.
This software tool locates and computes the intensity of radiation skin dose resulting from fluoroscopically guided interventional procedures. It is comprised of multiple modules. Using standardized body specific geometric values, a software module defines a set of male and female patients arbitarily positioned on a fluoroscopy table. Simulated X-ray angiographic (XA) equipment includes XRII and digital detectors with or without bi-plane configurations and left and right facing tables. Skin dose estimates are localized by computing the exposure to each 0.01 × 0.01 m2 on the surface of a patient irradiated by the X-ray beam. Digital Imaging and Communications in Medicine (DICOM) Structured Report Dose data sent to a modular dosimetry database automatically extracts the 11 XA tags necessary for peak skin dose computation. Skin dose calculation software uses these tags (gantry angles, air kerma at the patient entrance reference point, etc.) and applies appropriate corrections of exposure and beam location based on each irradiation event (fluoroscopy and acquistions). A physicist screen records the initial validation of the accuracy, patient and equipment geometry, DICOM compliance, exposure output calibration, backscatter factor, and table and pad attenuation once per system. A technologist screen specifies patient positioning, patient height and weight, and physician user. Peak skin dose is computed and localized; additionally, fluoroscopy duration and kerma area product values are electronically recorded and sent to the XA database. This approach fully addresses current limitations in meeting accreditation criteria, eliminates the need for paper logs at a XA console, and provides a method where automated ALARA montoring is possible including email and pager alerts.
Peak skin dose; sentinal event; DICOM structured report dose; patient entrance reference point; fluoroscopy; interventional radiology; Joint Commission (JC); radiation dose; Digital Imaging and Communications in Medicine (DICOM)
Intramedullary nailing is a standard surgical procedure for fixation of proximal femoral fractures, but is associated with considerable radiation exposure for controlling the implant placement, due to the percutaneous insertion technique.
The aim of this study was the evaluation of potential benefits of 2D-fluoroscopic based navigation focused on the reduction of radiation exposure, a decrease of procedure time, as well as an increase of accuracy for Gamma3 nail insertions.
Twenty randomized Gamma3 nail insertions were performed in non-fractured synthetic femora according to the manufactures operation guidelines (group I) or with use of a 2D-fluoroscopic based navigation system (group II). Time of different steps of the procedure and the radiation exposure were measured, as well as the accuracy evaluated in postoperative CT scans.
Results and discussion
All Gamma3 nails were placed without any technical problems. Independent of the used procedure, the overall operating time (group I: 584 ± 99.2 sec; group II: 662 ± 64.9 sec; p=0.06) and accuracy of the final nail-positions were equivalent, but the radiation exposure was significantly reduced (92% reduction in fluoroscopic images and 91% reduction in fluoroscopic time, p< 0.01), using the 2D fluoroscopic based navigation procedure.
2D-fluoroscopic based navigation for Gamma3 nail insertion facilitates a relevant reduction of radiation exposure with equivalent accuracy of the final implant position and no prolonged operating time. This promising procedure modification is independent of different cephalomedullary implant manufacturers and specific implant designs, but needs to be evaluated in further clinical settings.
Femoral fracture; Navigation; Gamma nail; Geriatric traumatology; Computer assisted surgery; Fluoroscopic navigation; Proximal femoral nailing; Cephalomedullary nail; Trochanteric fracture; Radiation exposure
C-arm fluoroscope has been widely used to promote more effective pain management; however, unwanted radiation exposure for operators is inevitable. We prospectively investigated the differences in radiation exposure related to collimation in Medial Branch Block (MBB).
This study was a randomized controlled trial of 62 MBBs at L3, 4 and 5. After the patient was laid in the prone position on the operating table, MBB was conducted and only AP projections of the fluoroscope were used. Based on a concealed random number table, MBB was performed with (collimation group) and without (control group) collimation. The data on the patient's age, height, gender, laterality (right/left), radiation absorbed dose (RAD), exposure time, distance from the center of the field to the operator, and effective dose (ED) at the side of the table and at the operator's chest were collected. The brightness of the fluoroscopic image was evaluated with histogram in Photoshop.
There were no significant differences in age, height, weight, male to female ratio, laterality, time, distance and brightness of fluoroscopic image. The area of the fluoroscopic image with collimation was 67% of the conventional image. The RAD (29.9 ± 13.0, P = 0.001) and the ED at the left chest of the operators (0.53 ± 0.71, P = 0.042) and beside the table (5.69 ± 4.6, P = 0.025) in collimation group were lower than that of the control group (44.6 ± 19.0, 0.97 ± 0.92, and 9.53 ± 8.16), resepectively.
Collimation reduced radiation exposure and maintained the image quality. Therefore, the proper use of collimation will be beneficial to both patients and operators.
collimation; image quality; radiation absorbed dose; radiation exposure
Exposure to radiation over many years increases the incidence of cataracts and promotes the development of carcinoma of the thyroid gland. A prospective study of 24 operative procedures involving minimal invasive techniques and fluoroscopic guidance was undertaken in order to measure the radiation exposure to the primary surgeon. The study was conducted during 8 K-wire osteosyntheses in fractures of the distal radius, 8 closed interlocking intramedullary nailings in fractures of the femur and 8 internal fixator procedures, with or without posterior autogenic transpedicular bone grafting, in fractures of the lumbar spine. Radiation was monitored with the use of high sensitive thermoluminescent dosimeters. Fluoroscopy was necessary during the procedures, with exposure times ranging from 55 s to 12 min 35 s. The radiation dose received per procedure ranged from 0.6–259.3 μSv and was well within the dose limits set by German law.
ABSTRACT Analysis for chromosome aberrations in human peripheral blood lymphocytes has been developed as an indicator of dose from ionising radiation. This paper outlines the mechanism of production of aberrations, the technique for their analysis and the dose-effect relationships for various types of radiation. During the past ten years the National Radiological Protection Board has developed a service for the UK in which estimates of dose from chromosome aberration analysis are made on people known or suspected of being accidentally over-exposed. This service can provide estimates where no physical dosemeter was worn and is frequently able to resolve anomalous or disputed data from routine film badges. Several problems in the interpretation of chromosome aberration yields are reviewed. These include the effects of partial body irradiation and the response to variations in dose rate and the intermittent nature of some exposures. The dosimetry service is supported by a research programme which includes surveys of groups of patients irradiated for medical purposes. Two surveys are described. In the first, lymphocyte aberrations were examined in rheumatiod arthritis patients receiving intra-articular injections of colloidal radiogold or radioyttrium. A proportion of the nuclide leaked from the joint into the regional lymphatic system. In the second survey a comparison was made between the cytogenetic and physical estimates of whole body dose in patients receiving iodine 131 for thyroid carcinoma.
Precise tunnel positioning is crucial for success in anterior cruciate ligament (ACL) reconstruction. The use of intra-operative fluoroscopy has been shown to improve the accuracy of tunnel placement. Although radiation exposure is a concern, we lack information on the radiation risk to patients undergoing fluoroscopically-assisted ACL reconstruction with a standard C-arm. The aim of our study was to determine the mean radiation doses received by our patients.
PATIENTS AND METHODS
Radiation doses were recorded for 18 months between 1 April 2007 and 30 September 2008 for 58 consecutive patients undergoing ACL reconstruction assisted by intra-operative fluoroscopy. Dose area product (DAP) values were used to calculate the entrance skin dose (ESD), an indicator of potential skin damage and the effective dose (ED), an indicator of long-term cancer risk, for each patient.
The median age of 58 patients included in data analysis was 28 years (range, 14–52 years), of whom 44 were male (76%). The mean ESD during intra-operative fluoroscopy was 0.0015 ± 0.0029 Gy. The mean ED was 0.001 ± 0.002 mSv. No results exceeded the threshold of 2 Gy for skin damage, and the life-time risk of developing new cancer due to intra-operative fluoroscopy is less than 0.0001%.
Radiation doses administered during fluoroscopically-assisted ACL reconstruction were safe and do not represent a contra-indication to the procedure.
Anterior cruciate ligament; Reconstruction; Intra-operative fluoroscopy; Radiation dose; Radiation risk
The main emphasis of a provincial radiation protection program is on ionizing radiation produced by machines, although assistance is given to the Federal Radiation Protection Division in its program relating to radioactive substances. The basis for the Saskatchewan program of radiation protection is the Radiological Health Act 1961. An important provision of the Act is annual registration of radiation equipment. The design of the registration form encourages a “do-it-yourself” radiation and electrical safety inspection.
Installations are inspected every two years by a radiation health officer. Two hundred and twenty-one deficiencies were found during inspection of 224 items of radiation equipment, the commonest being failure to use personal film badges. Insufficient filtration of the beam, inadequate limitation of the beam, and unnecessary exposure of operators were other common faults.
Physicians have a responsibility to weigh the potential advantages against the hazards when requesting radiographic or fluoroscopic procedures.
We monitored image intensifier use by orthopaedic trainees to assess their exposure to ionising radiation and to investigate the influence of sub-specialty training.
MATERIALS AND METHODS
Five different orthopaedic registrars recorded their monthly image intensifier screening times and exposure doses for all cases (trauma and elective), for a combined total of 12 non-consecutive months. Radiation exposure was monitored using shoulder and waist film badges worn both by surgeons and radiographers screening their cases.
Registrars in spinal sub-specialties were exposed to significantly higher doses per case and cumulative doses per month than non-spinal trainees (P < 0.05), but significantly lower screening times per case (P < 0.05). There were no significant differences in cumulative screening times per month (P > 0.05). Regression analysis for all surgeons showed a significant relationship between shoulder film badge reading and cumulative dose exposed per month (P < 0.05), but not for cumulative screening time. Shoulder film badge recordings were significantly higher for spinal compared with non-spinal registrars (P < 0.05), although all badges were below the level for radiation reporting. Only one radiographer badge recorded a dose above threshold.
Whilst the long-term effects of sub-reporting doses of radiation are not fully understood, we consider that this study demonstrates that trainees should not be complacent in accepting inadequate radiation protection. The higher doses encountered with spinal imaging means that sub-specialty trainees should be alerted to the risk of their increased exposure. The principle of minimising radiation exposure must be maintained by all trainees at all times.
Radiation; Orthopaedics; Spine surgery
Percutaneous vertebroplasty (PV) is generally performed under fluoroscopic guidance. Technically, single fluoroscope is considered sufficient for effectively monitoring PV. However, single fluoroscopic technique might be time-consuming in rotating the C-arm of the fluoroscope for either antero-posterior (AP) or lateral radiographic view, and causing delay in detecting cement leakage that can occur if the correct sight is not given. The aim of the current investigation was to compare the efficacy and safety of performing PV using one or two sets of fluoroscope.
This retrospective study enrolled 43 patients with painful osteoporotic vertebral fractures and they were treated with one-level PV. A single orthopaedic surgeon operated on all these patients. The patients were divided into two groups on the basis of the method of fluoroscopic control. In Group 1 (15 patients), PV was performed under the assistance of one fluoroscope. In Group 2 (28 patients), PV was performed under the control of two fluoroscopes. The mean follow-up was 19 months (range, 12 to 30).
Neither symptomatic cement leakage nor postoperative infection was found in both groups. The mean operation time in Group 2 was shorter, 37.8 vs. 31.0 minutes for Groups 1 and 2, P = 0.03. The incidence of cement leakage for Groups 1 and 2 was 26.7% (4/15) vs. 14.3% (4/28), respectively, P = 0.19.
We found that the two-fluoroscopic technique can provide simultaneous, real-time AP and lateral radiographic views to monitor entry point and cement delivery for PV and therefore reduce the operation time. The two-fluoroscopic technique did not require a complex manpower organization and has been proved to be a safe and effective technique for PV.
Insertion of percutaneous iliosacral screws with fluoroscopic guidance is associated with a relatively high screw malposition rate and long radiation exposure. We asked whether radiation exposure was reduced and screw position improved in patients having percutaneous iliosacral screw insertion using computer-assisted navigation compared with patients having conventional fluoroscopic screw placement. We inserted 26 screws in 24 patients using the navigation system and 35 screws in 32 patients using the conventional fluoroscopic technique. Two subgroups were analyzed, one in which only one iliosacral screw was placed and another with additional use of an external fixator. We determined screw positions by computed tomography and compared operation time, radiation exposure, and screw position. We observed no difference in operative times. Radiation exposure was reduced for the patients and operating room personnel with computer assistance. The postoperative computed tomography scan showed better screw position and fewer malpositioned screws in the three-dimensional navigated groups. Computer navigation reduced malposition rate and radiation exposure.
Level of Evidence: Level II, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.
Vertebroplasty and kyphoplasty are well-established minimally invasive treatment options for compression fractures of osteoporotic vertebral bodies. Possible procedural disadvantages, however, include incomplete fracture reduction or a significant loss of reduction after balloon tamp deflation, prior to cement injection. A new procedure called “vertebral body stenting” (VBS) was tested in vitro and compared to kyphoplasty. VBS uses a specially designed catheter-mounted stent which can be implanted and expanded inside the vertebral body. As much as 24 fresh frozen human cadaveric vertebral bodies (T11-L5) were utilized. After creating typical compression fractures, the vertebral bodies were reduced by kyphoplasty (n = 12) or by VBS (n = 12) and then stabilized with PMMA bone cement. Each step of the procedure was performed under fluoroscopic control and analysed quantitatively. Finally, static and dynamic biomechanical tests were performed. A complete initial reduction of the fractured vertebral body height was achieved by both systems. There was a significant loss of reduction after balloon deflation in kyphoplasty compared to VBS, and a significant total height gain by VBS (mean ± SD in %, p < 0.05, demonstrated by: anterior height loss after deflation in relation to preoperative height [kyphoplasty: 11.7 ± 6.2; VBS: 3.7 ± 3.8], and total anterior height gain [kyphoplasty: 8.0 ± 9.4; VBS: 13.3 ± 7.6]). Biomechanical tests showed no significant stiffness and failure load differences between systems. VBS is an innovative technique which allows for the possibly complete reduction of vertebral compression fractures and helps maintain the restored height by means of a stent. The height loss after balloon deflation is significantly decreased by using VBS compared to kyphoplasty, thus offering a new promising option for vertebral augmentation.
Vertebral body stenting; Vertebroplasty; Kyphoplasty; Osteoporosis; Vertebral compression fracture
The C-arm fluoroscope is an essential tool for the intervention of pain. The aim of this study was to investigate the radiation exposure experienced by the hand and chest of pain physicians during C-arm fluoroscopy-guided procedures.
This is a prospective study about radiation exposure to physicians during transforaminal epidural steroid injection (TFESI) and medial branch block (MBB). Four pain physicians were involved in this study. Data about effective dose (ED) at each physician's right hand and left side of the chest, exposure time, radiation absorbed dose (RAD), and the distance from the center of the X-ray field to the physician during X-ray scanning were
Three hundred and fifteen cases were included for this study. Demographic data showed no significant differences among the physicians in the TFESIs and MBBs. In the TFESI group, there was a significant difference between the ED at the hand and chest in all the physicians. In physician A, B and C, the ED at the chest was more than the ED at the hand. The distance from the center of the X-ray field to physician A was more than that of the other physicians, and for the exposure time, the ED and RAD in physician A was less than that of the other physicians. In the MBB group, there was no difference in the ED at the hand and chest, except for physician D. The distance from the center of the X-ray field to physician A was more than that of the other physicians and the exposure time in physician A was less than that of the other physicians.
In conclusion, the distance from the radiation source, position of the hand, experience and technique can correlate with the radiation dose.
distance; exposure time; radiation dose; radiation protection