Minimally invasive surgery and radiation exposure

Non-invasive and quantitive analysis of flatfoot based on ultrasound

Flatfoot is a common foot deformity that seriously affects the quality of life. The aim of this study is to develop an accurate and noninvasive method for the diagnosis of flatfoot based on B-mode ultrasound. In this study, 51 patients (the flatfoot group) and 43 healthy subjects (the control group) were included. The plantar fascia angle, a new measurement for use in the diagnosis of flatfoot is proposed, as determined using B-mode ultrasound. For comparison, the calcaneal pitch angle and medial cuneiform height were also measured using lateral X-radiography, based on traditional diagnostic methods. The intraclass correlation values of the plantar fascia angle, the calcaneal pitch angle, and the medial cuneiform height were all more than 0.95, and there is a moderate correlation (r = 0.51) between the medial cuneiform height and the calcaneal pitch angle, and an excellent correlation (r = 0.85) between the plantar fascia angle and the calcaneal pitch angle. The optimal cutoff value, sensitivity, and specificity for medial cuneiform height in flatfoot diagnosis were 12.8 mm, 93.0%, and 54.9%, respectively. The optimal cutoff value, sensitivity, and specificity for plantar fascia angle in flatfoot diagnosis were 9.8°, 97.7%, and 94.1%, respectively. The proposed plantar fascia angle has good sensitivity and specificity in diagnosing flatfoot, therefore supplying a new approach for the noninvasive diagnosis of flatfoot.

Computed Tomography-Based Navigation System in Current Spine Surgery: A Narrative Review

The number of spine surgeries using instrumentation has been increasing with recent advances in surgical techniques and spinal implants. Navigation systems have been attracting attention since the 1990s in order to perform spine surgeries safely and effectively, and they enable us to perform complex spine surgeries that have been difficult to perform in the past. Navigation systems are also contributing to the improvement of minimally invasive spine stabilization (MISt) surgery, which is becoming popular due to aging populations. Conventional navigation systems were based on reconstructions obtained by preoperative computed tomography (CT) images and did not always accurately reproduce the intraoperative patient positioning, which could lead to problems involving inaccurate positional information and time loss associated with registration. Since 2006, an intraoperative CT-based navigation system has been introduced as a solution to these problems, and it is now becoming the mainstay of navigated spine surgery. Here, we highlighted the use of intraoperative CT-based navigation systems in current spine surgery, as well as future issues and prospects.

ESTIMATED EXPOSURE OF SPINE SURGEONS TO RADIATION

ABSTRACT Objective To estimate the amount of radiation received and accumulated in the bodies of two surgeons, one being the responsible surgeon and the other the assistant, performing spine surgery procedures over a period of 25 years. Methods Seventy-two spinal surgeries were performed during a seven-month period and the radiation loads were measured in both surgeons. The measurement of radiation was captured in fluoroscopy in anteroposterior and lateral incidences. The surgeon and the assistant used two dosimeters, one in the cervical region protecting the thyroid and the other on the lead apron in the genital region. The radioactive loads were measured in millisieverts and the accumulated charges were recorded monthly in both regions of the body in the two surgeons for seven months and the means for the work periods (1, 5, 10, 15, 20 and 25 years) were estimated. Results It was observed that in the surgeon the average accumulated radiation loads were 131.9% and 176.92% higher than those of the assistant in the cervical and genital regions, respectively. Conclusion While the use of X-rays is indispensable in routine orthopedic surgery, we have to consider the development of techniques of protection, rigor and discipline in the use of safety materials for surgeons. Preventive exposure reduction measures such as using thyroid protection equipment and turning the head away from the patient during fluoroscopy, among others, should be mandatory to promote less radiation exposure. Level of evidence II; Comparative prospective study.

Measurements of surgeons' exposure to ionizing radiation dose during intraoperative use of C-arm fluoroscopy

STUDY DESIGN

Measurement of radiation dose from C-arm fluoroscopy during a simulated intraoperative use in spine surgery. OBJECTIVE.: To investigate scatter radiation doses to specific organs of surgeons during intraoperative use of C-arm fluoroscopy in spine surgery and to provide practical intraoperative guidelines.

SUMMARY OF BACKGROUND DATA

There have been studies that reported the radiation dose of C-arm fluoroscopy in various procedures. However, radiation doses to surgeons' specific organs during spine surgery have not been sufficiently examined, and the practical intraoperative radioprotective guidelines have not been suggested.

METHODS

Scatter radiation dose (air kerma rate) was measured during the use of a C-arm on an anthropomorphic chest phantom on an operating table. Then, a whole body anthropomorphic phantom was located besides the chest phantom to simulate a surgeon, and scatter radiation doses to specific organs (eye, thyroid, breast, and gonads) and direct radiation dose to the surgeon's hand were measured using 4 C-arm configurations (standard, inverted, translateral, and tube translateral). The effects of rotating the surgeon's head away from the patient and of a thyroid shield were also evaluated.

RESULTS

Scatter radiation doses decreased as distance from the patient increased during C-arm fluoroscopy use. The standard and translateral C-arm configurations caused lower scatter doses to sensitive organs than inverted and tube translateral configurations. Scatter doses were highest for breast and lowest for gonads. The use of a thyroid shield and rotating the surgeon's head away from the patient reduced scatter radiation dose to the surgeon's thyroid and eyes. The direct radiation dose was at least 20 times greater than scatter doses to sensitive organs.

CONCLUSION

The following factors could reduce radiation exposure during intraoperative use of C-arm; (1) distance from the patient, (2) C-arm configuration, (3) radioprotective equipments, (4) rotating the surgeons' eyes away from the patient, and (5) avoiding direct exposure of surgeons' hands.