Wire Markers Research Articles

Preoperative spinal localization using the hook wire technique

Surgeons are increasingly required to resect disk herniations. Methods for preoperative or perioperative localization of such lesions require precision. This is difficult to achieve using the usual methods. We propose the use of a preoperative invasive technique: needle and marker wire. Its precision has been proved for preoperative localization of nonpalpable breast lesions.

Markers for implanted devices: need for standardization.

Some preventable diagnostic problems and risks related to medical devices indicate the need for logical marker standards and for input from radiologists in the design of these devices. The problems range from undetectable items inserted in the body to external equipment that needlessly hides detail on radiographs. The variety and absolute numbers of such devices used in patient care and monitoring are rapidly increasing. Some voluntary standardsfor radiologic detectability exist, but there is no organized method for the dissemination of these standards. A surprising variety of important devices are invisible or poorly opaque, ensuring lack of detection by radiography. These include venous catheters, vascular grafts, heart valve and breast prostheses, feeding tubes, and even ventricular shunts. Abstract markers for surgical sponges and pads can be mistaken for drains, surgical clips, or wire sutures [1 , 2]. Single wire markers found in tubes, aortic balloons, and venous catheters are similar to transcutaneous nerve stimulators and electrocardiographic leads. Rarely used specialty prostheses can be confusing without a detailed clinical history. All devices intentionally placed in patients or left in accidentally pose risks of infection, breakage, and displacement. Tubes and grafts may obstruct or leak. Casts, braces, and other external equipment can hide underlying anatomy and pathology. Dressings and stopcocks may cause confusing radiographic shadows. The following examples from a large hospital illustrate these problems (figs. 1-8). Discussion

Ｃｈａｒｎｌｅｙ式ＴＨＲのソケットの摩耗度測定法に関する一考案

With this method socket wears ware measured in 7 hips of Charnley THR cases. However, the result was not always constant.The principle of this method is that in two radiographs taken over a period of time, displacement of the center of the metal head, in relation to the center of the wire marker's elliptical curve, shows the socket wear over a given period of time.With this method socket wears were measured in 7 hips of Charnley THR cases. However, the result was not always constant.It is possible to know the degree and direction of the socket wear in two-dimentions by using this method. However, there are some problems such as the technical difficulties and the necessity to get two radiographs taken with the same direction.It seems that the inconstancy of the results may be due to those problems.

Roentgenographic Evaluation of Geometric Total Knee Arthroplasty with a Six-Year Average Follow-up Period

The geometric total knee prosthesis was used in the reconstruction of 70 damaged knee joints in 56 patients from November 1973 through March 1979. The average follow-up period extended to six years and seven months. Eleven patients had died and four could not be located. Eighty-one percent of the remaining knees had little or no pain at the time of the review. Pain in the patellofemoral joints was an insignificant problem in this series. The femorotibial shaft angle ranged from 0 degrees to 10 degrees of valgus in 43 (82.7%) of 52 knees. Six knees showed varus deformity at the time of follow-up examination. Stress fracture of the medial condyle of the tibia was found in two of these six knees. The absence of a radiolucent zone at the tibial cement-bone interface was noted in only ten (19.2%) of the 52 knee roentgenograms. New formation or progression of a radiolucent zone from six to 12 months after the operation was found in 36.5%. Positional abnormality of the marker wires seen in serial roentgenograms existed in 51.9% of the knees. Nine knees (17.3%) disclosed a gap between the metallic articular surface and the tibial component and also showed the collision of the tibial intercondylar eminence against the femur in the standing position. The tibial component of the prosthesis was fractured in one knee.

A Method for the Geometric and Densitometric Standardization of Intraoral Radiographs

The interpretation of dental radiographs for the diagnosis of periodontal disease conditions poses several difficulties. These include the inability to adequately reproduce the projection geometry and optical density of the exposures. In order to improve the ability to extract accurate quantitative information from a radiographic survey of periodontal status, a method was developed which provided for consistent reproduction of both geometric and densitometric exposure parameters. This technique employed vertical bitewing projections in holders customized to individual segments of the dentition. A copper stepwedge was designed to provide densitometric standardization, and wire markers were included to permit measurement of angular variation. In a series of 53 paired radiographs, measurement of alveolar crest heights was found to be reproducible within approximately 0.1 mm. This method provided a full mouth radiographic survey using seven films, each complete with internal standards suitable for computer-based image processing.

Preoperative localization of nonpalpable breast lesions using a wire marker and perforated mammographic grid.

Preoperative wire localization of mammographically identified nonpalpable breast lesions is facilitated by using a perforated mammographic compression plate. This device is used in conjunction with a self-retaining wire, and its use results in accurate placement of the wire-marker tip in close proximity to the mammographically suspicious lesion. In 39 of 47 lesions, the wire tip was within 1.0 cm of the lesion, and in 45 of 47 lesions, the wire tip was within 1.5 cm of the lesion.

Suctioning the left bronchial tree in the intubated adult.

The influence of various factors on left bronchial tree suctioning was assessed using suction catheters containing a radiopaque wire marker. In the control group, the left bronchial tree was entered in 33% of attempts through endotracheal tubes and 29% of attempts through tracheostomy tubes. Manipulation of either the trachea or the tracheostomy tube did not increase left bronchial entry. A curved-tip catheter significantly improved left bronchial entrance rate when passed through tracheostomy tubes (p < 0.05), but not when passed through endotracheal tubes.

Elongation in profundus tendon repair. A clinical and radiological study.

A radiographical study of 63 digits with tendon lacerations within the digital sheath is presented. 60 of these digits were evaluated clinically 6-36 months (mean 15 months) after surgery. At primary tendon repair one wire marker was placed on each side of the repair site in the profundus tendon. The distance between the markers was measured at operation and postoperatively on 3 different occasions on radiograms. The results showed that increase of the distance between the markers by more than 5 mm, considered to indicate elongation in the suture, occurred in 25 out of 59 repaired profundus tendons (42%) and in most instances this happened during the period of immobilization. The cause of elongation could be identified in 9 digits. In 5 it was due to rupture of the suture material, the tendons being repaired with 5-0 Flexon steel wire. In the other 4 digits, sutured with 4-0 Silky Polydec, slipping of the knot was revealed at reoperation. There was a strong correlation between increased distance between the markers and a poor outcome, elongation being the most frequent cause.

The effect of posterior spinal fixation with bone cement upon vertebral growth in dogs. An experimental study.

In an experimental study the authors tried to clarify the effect on vertebral growth and spinal curvature in dogs following fixation of the posterior elements of the spine at different levels using bone cement. In three separate experimental groups a segment of the dorsal spine, the dorso-lumbar spine or the lumbar spine was securely fixed with bone cement incorporating a radio-opaque wire marker. Growth of the spine was observed with renal X-rays over a six-month period and the following results obtained: 1. Growth in height of the vertebra was not affected by the fixation; 2. The intervertebral disc spaces widened anteriorly and narrowed posteriorly even when fracture of the bone cement occurred; 3. Increasing lordosis developed in all three experimental groups even when a physiological kyphosis was normally present. The greatest increase occurred in the lumbar spine; 4. Fracture of the cement occurred consistently when attempting to secure the dorso-lumbar junction.

Investigation of the high-temperature oxidation of Fe-Cr alloys by means of the isotope18O

The mechanism of oxidation at 1000°C of Fe-Cr alloys has been investigated. The samples were oxidized in two stages: first in an atmosphere of16O and subsequently in16O. Prior to each stage the samples had been marked with platinum wire markers. The concentration of18O in the scale was determined by means of two nuclear reactions:18O(α,n)21Ne, and18O(p,n)18F independently. The results show that the dissociative mechanism of scale growth on Fe-Cr alloys is similar to that found earlier for Cu-Zn type alloys for which measurements were made using the radioactive sulfur isotope,35S.

Self-diffusion of alpha-iron in a large temperature gradient

Experimental results of an attempt to measure the thermal gradient self-diffusion in iron are given. A temperature gradient of 2500°C/cm was placed on each of three iron samples for 550 hr. Platinum wire markers were placed 0.01 in. apart, normal to the sample length; the marker spacings were measured before and after the diffusion anneal. No marker shift greater than the 0.0001-in. probable error was observed; whereas marker shifts of the order of 0.001 in. were anticipated from theoretical calculations. Each of several alternative possible conclusions which may be drawn from these results are discussed: 1. (1) self-diffusion in α-iron is not via a vacancy mechanism, or 2. (2) if the vacancy mechanism predominates in α-iron, then either 1. (a) the activation energies for formation, E f , and migration of vacancies, E m , are nearly equal, or 2. (b) the role of the barrier atoms must be explicitly considered in the process of thermal activation for an atom jump in a temperature gradient, in which case the mass flow is not proportional to the difference in E f and E m . The model of thermal gradient self-diffusion is discussed and several experiments are suggested. In addition, a calculation is given for the dependence of thermal gradient self-diffusion on the separation of vacancy sources and sinks, using parallel grain boundaries normal to the temperature gradient as the only sources and sinks which are important.

Analogy to the Kirkendall Effect in the Gas Phase

THE Kirkendall effect1 was first observed as a movement of fine molybdenum wire markers in a contact plane between brass and copper during interdiffusion. If diffusion occurs by a random walk movement of individual atoms, then, no matter what theory is employed for their detailed motion, it is difficult to see how it could produce movement of markers. Darken2 considered that diffusion of copper and zinc occurred in opposite directions, at independent rates, and that the difference was compensated by a ‘bulk flow’. If it fails to occur, voids are left behind by the more rapidly moving component, and this result of diffusion in metals has in fact been observed3.

Methods of marking the plane of section in the open lobotomy operation.

A number of methods have been devised for visualizing the plane of section following lobotomy. Lipiodol was used successfully for this purpose by Freeman and Watts (1), but in the “open” lobotomy the lipiodol may fall to the basal cisterns or enter the lateral ventricles and be distributed throughout the spinal fluid pathways of the brain and spinal cord. A gross method used by the authors and others has been the application of silver clips at the base, mid-portion, and apex of the vertical plane of section in the open operation. An angled clip applicator is useful for insertion of these clips at the base of the plane of section. Putnam (2) first suggested the use of tantalum wire markers in various types of lobotomy. For the standard open lobotomy operation and for cortical under cutting of selected areas of the prefrontal cortex (as performed by Scoville), the authors have used 30-gauge stainless steel wire loops as markers, bending the tips of the loops backward upon themselves in order to blunt them (...

A comparison of percussion and radiography in locating the heart and superior mediastinal vessels

The deep dullness of heart and superior mediastinal vessels was percussed on 110 male university students (erect and recumbent) by one physician, wire markers were fastened to their chests, and teleoradiographic films were taken. All results were analyzed statistically. In these students the mean errors (difference between percussion and x-ray borders) were less than 1 cm. in most intercostal spaces; but much greater allowance for possible error had to be made in percussing any one individual—for example, a range of over 3.5 cm. in the fourth left intercostal space in erect students. The differences in error between erect and recumbent positions could be largely attributed to dispersion of x-rays. For practical purposes the variation between two percussions on the same student was as great as between different students because the correlation between the errors in repeated percussion of the same students, although significant, was low. From one-third to one-half of the variation in the cardiac (but not the superior mediastinal) region was attributable to diaphragm movement, owing to the impossibility of securing the same midphase of respiration on any two occasions. The risk of wide error in any individual percussion could be greatly lessened by taking the average of several independent readings, thereby reducing the effect of diaphragm movement. Stature, weight, and chest size or shape had no important relationship to the percussion error. Ten students, taken at random, sufficed to show the difference in error of two experienced physicians. Since each observer should know his own percussion error, the amount of information obtainable from a small series of films is illustrated.