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PubMedDate not supplied

[Ionization chambers with preamplifiers for X-ray exposure metering systems].

Ionization chambers with preamplifiers available from SpektrAp, Ltd., are described. The ionization chambers are intended for use in X-ray automatic exposure systems of diagnostic X-ray apparatuses. The ionization chambers provide automated matching of their sensitivity to the sensitivity of modern intensifying screens. The preamplifier provides direct integration of the ionization chamber current. It can operate within the entire dose rate range of the roentgenographic mode and meets the requirements of modern diagnostic X-ray detectors to the dose range. Special techniques for increasing the noise immunity of preamplifiers are described. Performance specifications of the ionization chambers and preamplifiers are given.

Air Ionization↗

PubMed1994

Hip arthroplasty for failed internal fixation of intertrochanteric and subtrochanteric fractures in the elderly patient.

Nine elderly patients were treated by salvage hip arthroplasty following failed internal fixation of an intertrochanteric or subtrochanteric hip fracture. The mean age at time of fracture was 79 years (range 67-94 years). The mean interval from initial fracture fixation to conversion arthroplasty was 7 months (range 5 days to 19 months). One 84-year-old patient died 6 weeks postoperatively from a pulmonary infection. The remaining eight patients were assessed clinically and roentgenographically after a mean follow-up period of 41 months (range 4-85 months). The functional results, rated according to the Merle d'Aubigné hip rating scale, were excellent in one patient, very good in four patients, good in two patients, and fair in one patient. Serial roentgenographic analysis showed new bone formation around the extramedullary part of the femoral component in all these patients and bone remodelling of the diaphyseal part of the femur in all patients. The preservation of the functional continuity of the abduction apparatus during surgery and the early walking with full unrestricted weight-bearing made possible by the arthroplasty are considered to be the major contributing factors to these results.

Aged↗

PubMed1978

[Lymphographic data variants in cerival cancer after Wertheim's extended hysterectomy].

Lymphography data in 53 patients previously operated upon for cervical cancer were analysed. The results obtained enabled the author to state that the application of roentgenological investigation of the lymphatic system after Wertheim's radical operation makes it possible to define how adequately the iliac lymph apparatus was removed and also to recognize the presence of postoperative retroperitoneal lymph cysts. But the method is of little informative value, if it is necessary to settle whether metastases and recurrence are present or not. This is due to the fact that on roentgenographs changes related with traumatic injury to lymph nodes and vessels appear to be identical to the character of tumor-induced injuries.

Adult↗

PubMed1979

Classification of oblique facial clefts with microphthalmia.

We believe the Tessier classification system facilitates the description of complicated facial clefts, and we describe its use in 4 cases--all of whom had variations of a Tessier-3 cleft. Microphthalmia is associated with the Tessier-3 cleft. Computerized axial tomography may be helpful in differentiating an extreme microphthalmia from a true anophthalmia, and in detecting bony clefts not seen on roentgenographic studies. Facial tomograms show that abnormalities of the medial wall of the orbit in the Tessier-3 cleft vary from actual clefts to widening of the ethmoid. In our experience (with 4 patients) mental retardation does not necessarily occur in patients with the Tessier-3 cleft and extreme microphthalmia. Abnormalities of the nasolacrimal apparatus may be the most constant finding in patients with the Tessier-3 cleft. Children with the Tessier-3 cleft should be identified early for purposes of determining the proper treatment and valid genetic counseling.

Anophthalmos↗

PubMed1995

Staggering gait in medical history.

Drunkenness and senility were recognized early as the basis of a staggering gait. To these were added venereal excesses, hence syphilis. Medical and scientific concerns began to be focused on "locomotor ataxia" in the 19th century with the systematic development of neuroanatomy and physiology. Rolando and Flourens were followed by Romberg and Todd, and later Friedreich, who all gave the spinal cord temporal precedence as a culprit over the cerebellum--and there were some forerunners. New spinal sensory pathways were delineated by Goll, Flechsig, and Gowers. In France, we must specially credit Duchenne as well as Bouillaud, and later Babinski, Marie, and Dejerine, for correcting, differentiating, extending, and underpinning current concepts. Failures of input and output, of conduction and central coordination were invoked and explained, among them the vestibular apparatus, as well as the causation by neoplasms, demyelination, degeneration, and infarction affecting even the frontal lobe, thalamus, and basal ganglia. Clinical testing was brought up to 20th-century standards essentially by Sherrington and Bárány, followed by Dandy, the neurosurgeon who showed how to replace ventricular fluid by air, more recently made obsolete by modern roentgenographic procedures. And tabes dorsalis, once the chief culprit, has practically become a medical anachronism thanks to penicillin.

Ataxia↗

PubMed1980

Use of the Hoffmann apparatus in the treatment of unstable tibial fractures.

The Hoffmann apparatus was employed in the treatment of thirty-four complex tibial fractures that we considered to have a poor prognosis with more conventional forms of treatment. Complications were minimum. The time to union for all of the fractures averaged 5.8 months and appeared to be directly related to the accuracy of the reduction. In twenty-five fractures in which it was possible to achieve an anatomical reduction and to apply compression through the apparatus, the time to union averaged 5.1 months. In six fractures that could not be anatomically reduced and compressed, the time to union averaged 8.2 months. Shortening or significant angulation of the fractures did not occur. The accessibility of the wound for serial débridement and the stabilization of the fracture as well as the traumatized soft tissue were thought to be of great value in preventing deep wound infection. A retrospective evaluation of many of the healed fractures revealed roentgenographic evidence of primary bone-healing without visible callus. Knowledgeable application of the principles and biomechanics of primary bone-healing are essential for successful treatment by this method.

Adult↗

PubMed1982

[Critical study of patella alta. II. Patella alta and femoropatellar pathology].

Patella alta is radiologically defined by an Insall index equal to or greater than 1.3. In 50 patients suffering from pain of the femur and patella, roentgenographic studies consisting of a simple profile view and occasionally completed by a view through Smillie's angle with the knee hyperextended, revealed patella alta. The stretching of the patellar tendon is facilitated by excessive tension during growth and by excessively strenuous physical exercises; patella alta can occasionally be complicated by Osgood-Schlatter's or Sinding-Larsen Johansson's disease. Ruptured tendons have occasionally been observed. Genu recurvatum can also lead to patella alta. The joint should be routinely examined for excessive mobility. Patella alta is often associated with various affections of the extensor apparatus of the knee: pathology secondary to injury, external malposition, gonarthrosis, supratrochlear erosions of the femur. The importance of the role of this condition with respect to patellar chondromalacia has been estimated to varying degrees. The diagnosis of patella alta should be considered in all cases of knee pain.

Adolescent↗

PubMed1979

Contour analysis in plastic and reconstructive surgery.

Three-dimensional measurements of living objects may be made using various biostereometric techniques. Moire topography provides one-step contour line maps. It is a potential low-cost adjuvant to current photographic and cephalometric techniques for documentation of surface deformities. A relatively simple apparatus may be used with instant-processing film to produce immediate contour maps superimposed on the object image on the film. There is significant qualitative information highlighted by the fine resolution of the system. This immediate had data may be quantitatively analyzed by hand with ruler and/or caliper. In the future, off-line quantitative analysis may be made by computer. Geometric constraints of the system and examples of use of the technique are provided. Emphasis is placed on facial asymmetries that are difficult to analyze from plain photographs and inaccessible to data analysis from lateral cephalometric roentgenographs.

Adolescent↗

PubMed1980

[Quality control of Roentgen equipment with automatic exposure using a newly developed test phantom. Part II: surface dose, image parameters and quality number (author's transl)].

The article reproduces further results of quality control tests conducted with 42 automatically exposed roentgenographs of a test phantom, for the parameters surface dose (Do), film-distant (AF) and film-proximal (AN) resolution, optical density of dominant (SDom), film contrast (KF) and size of focus. By means of definition of the quality number z = AN x AF/log10 x Do, it is possible to state the sequence of qualitatively different X-ray films and to plot this against log10 t to take organ movements into consideration, thus supplying a simple criterion of the quality of Roentgen equipment. Good equipment will yield values of z/log10 t = 3, whereas medium-quality and insufficiently equipped apparatus will yield values around 2 or 1, respectively, or even below this figure. If the values are too low, analysis of all data obtained with the test phantom will supply indications with regard to the possible causes. Of the 42 X-ray films tested in this study, the z/log10 t values were above 2 in 15 cases, and below 2 in the same number of cases. Variations in the size of focus, optical density of dominant and contrast, are shown in the diagrams and described quantitatively by their average values anad standard errors.

Models, Structural↗

PubMed1998

Effect of low-power laser irradiation on the mechanical properties of bone fracture healing in rats.

BACKGROUND AND OBJECTIVE: Low-power laser irradiation (LPLI) has been found to have a positive effect on bone fracture healing in animal models, based on morphogenic, biochemical, roentgenographic, and electron microscopic measurements. We investigated the effect of LPLI on bone fracture healing in rats using biomechanical methods. STUDY DESIGN/MATERIALS AND METHODS: Two groups of male Wistar rats, divided in a randomized block design in a blinded fashion, each consisting of 25 animals, were subjected to anesthesia and tibial bone fracture with internal fixation. The first group was treated with LPLI (HeNe laser 632.8 nm, 35 mW), applied transcutaneously over 30 minutes to the area of the fracture daily for 14 days. The second group served as a control. After 4 weeks, the tibia was removed and tested at tension up to failure (by a Lloyd LR 50K testing apparatus, U.K.) in 16 rats from group I and 15 from group II. The maximal load at failure, the structural stiffness of the tibia (callus stiffness), and the extension maximal load were measured. RESULTS: The maximal load at failure and the structural stiffness of the tibia were found to be elevated significantly in the irradiated group (P = .014 and P = .0023, respectively), whereas the extension maximal load was reduced (P = .015). In addition, gross non-union was found in four fractures in the control group, compared to none in the irradiated group. CONCLUSION: These results suggest that LPLI treatment may play a role in enhancing bone healing.

Animals↗

PubMed1985

External catheters: hazards and benefits of their use by men with spinal cord lesions.

Urinary tract status was reviewed in 60 men with spinal cord injury who had external bladder drainage from 1 to 159 months. Before use, 34 (57%) patients were free of roentgenographic abnormalities, and 27 (79%) of these developed changes. Twenty-six (43%) patients of the total group initially had morphologic defects; 5 (19%) of these became free of abnormalities, while 21 (81%) did not improve or showed progression. Glomerular filtration rate improved in 2 (3%) of the total study group, deteriorated in 12 (20%), and remained stable in 46 (77%). Infection persisted in 32 (53%); 10 (31%) of the positive cultures grew multiple isolates. In 18 (56%) of those patients with positive urine cultures, tissue invasion was indicated by the presence of antibody-coated bacteria. After external drainage 5 (8%) required sphincterotomy, 3 (5%) supravesical diversion, and 2 (2%) suprapubic cystotomy. Patient histories and examinations revealed tendencies toward poor hygiene and inattention to adequate bladder emptying. Equipment obstruction was common because of twisting or improper placement of drainage apparatus. It was concluded that although carefully monitored external catheters may accomplish adequate drainage and sterile urine, the hazards of infection and overdistention are great and must be countered by medical monitoring and ongoing patient education.

Catheters, Indwelling↗

PubMed1990

Conventional CT of the aorta.

The advent of CT has changed the way thoracic aortic aneurysms and dissections are evaluated. In many cases, CT is the only roentgenographic examination needed beyond plain radiograph. In evaluating aneurysm. CT's advantage over aortography is that it shows the wall and the mural thrombus, not just the contrast column. In some cases of aneurysm, however, particularly those arising near the aortic arch, aortography may be necessary to establish the precise location of the lesion with respect to the brachiocephalic arteries. In evaluating dissection, CT is less invasive and at least as accurate as aortography. As with aortography, the classic findings are contrast-filled multiple channels with intervening intimal flap(s). CT's particular advantage over aortography is that it permits diagnosis of dissection when blood in the false channel is clotted rather than free-flowing. In this case, the diagnosis can be made by demonstrating displaced intimal calcifications or the high-attenuation thrombus in the aortic wall or periaortic tissues. In cases of acute dissection for which emergency surgery is considered, however, aortography is preferred to CT because CT cannot provide information about aortic insufficiency or the condition of critical arterial branches such as the coronary, brachiocephalic, mesenteric, and renal arteries. In follow-up of treated aortic dissection CT is preferred over aortography because it is noninvasive and more informative. Compared with MRI, CT has the advantages of greater reliability and of compatibility with life-support apparatus. MRI is not able to depict calcification, so any displacement of calcification cannot be detected. MRI is most suitable for follow-up of treated patients or for acute patients who are stable or who cannot tolerate intravenous contrast agents. A flexible approach is essential in choosing the appropriate radiographic tests in the work-up of aortic dissection. In this article, a workable strategy is outlined, but the radiologist should not hesitate to change the order of tests or use a second test if results from one test are confusing or inconsistent with other clinical data.

Aortic Dissection↗