[Homogenization of unequally darkened roentgenograms; comment on W. Buchholz work: on simultaneous exposure of roentgenograms by means of equalizing foils].
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The current study examined whether a three hour roentgenogram of the chest was as reliable as the six hour roentgenogram of the chest in detecting delayed complications (that is, pneumothorax and hemothorax) of penetrating and nonpenetrating trauma to the chest. The 285 patients in the study were placed into three groups: those stabbed in either the chest or back; those sustaining multiple fractures of the ribs, and those with gunshot wounds to the chest or back. All the patients selected for study by three and six hour films of the chest were asymptomatic on admission and no pneumothorax or hemothorax was seen on initial anteroposterior and lateral roentgenograms of the chest. None of the patients included in the study required immediate operation. Twelve patients (4 percent) had delayed pneumothoraces on the three hour roentgenogram of the chest. Nine of these 12 (75 percent) required thoracostomy tube drainage, while the remaining three patients were managed with needle aspiration. No additional patients had complications on the six hour roentgenogram of the chest. Computed tomographic (CT) scan discovered five additional patients (2 percent) with pneumothoraces not visualized by the three or six hour films. Seventeen patients (6 percent) had delayed pneumothoraces despite negative admission roentgenograms of the chest and lack of symptoms. Twelve of the 17 (71 percent) were discovered on three hour roentgenogram of the chest, while an additional five of 17 (29 percent) were only seen by CT scan. Three hour roentgenograms of the chest are as reliable as six hour roentgenograms of the chest in visualizing the development of delayed complications of penetrating and nonpenetrating thoracic trauma. The CT scan is more effective than the roentgenogram of the chest in visualizing small pneumothoraces, but its use as a screening tool for detection of delayed complications of trauma to the chest pneumothoraces is probably cost-prohibitive.
An experimental model of the L4-L5 lumbar motion segment was developed that allowed precise manipulation of sagittal translation, rotation of L5 relative to L4, tilt of L4 on L5, and control of roentgenogram quality (image clarity) by placing a water bath between the tube and the vertebral body. A series of experiments were designed to systematically assess the consistency and accuracy of sagittal translation measurements from roentgenograms of varying quality, using different measurement protocols and various rater combinations on models with varying degrees of concomitant motions (rotations and tilts). Study 1 assessed the effects of roentgenogram quality, raters, and seven measurement methods on the consistency and accuracy of evaluating translations in the sagittal plane. Results indicated very high reliabilities across roentgenogram quality, raters, and measurement. As expected, high-quality roentgenograms were more accurately evaluated than lower-quality roentgenograms. However, closer inspection of the consequences of errors in measured translations indicated surprisingly high false-positive and false-negative rates, with significant differences observed between measurement methods. Study 2 assessed the effects of concomitant motions and measurement methods on the consistency and accuracy of evaluations. Within-rater consistency and accuracy indices were remarkably high and similar across measurement methods and degrees of concomitant motions. However, important differences in the false-positive and false-negative rates were again observed. Method 2, described by Morgan and King, demonstrated the overall best performance and the least interference due to concomitant motions. Study 3 assessed the effects of raters and measurement methods on the consistency of measuring translation in clinical roentgenograms, where concomitant motion factors may be present, but not explicitly considered. Results indicated substantially lower within- and between-rater consistency estimates relative to consistencies obtained from the model, although these magnitudes were similar to those reported by others evaluating clinical roentgenograms. The implications of lower consistency estimates relative to increased false-positive and false-negative rates must be more closely examined. These studies present evidence suggesting that high consistency and accuracy indices do not ensure acceptable false-positive and false-negative rates and, thus, provide empirical evidence supporting the view that using roentgenograms as a basis for diagnosing instability often can lead to errors in classification. This is less so when observed translations are relatively large (+/- 5+ mm) on roentgenograms that are relatively clear, with little obliquity, and when concomitant motions are minimal.(ABSTRACT TRUNCATED AT 400 WORDS)
Follow-up chest roentgenograms are a commonly performed test. We prospectively evaluated their diagnostic and therapeutic influence at a tertiary care teaching hospital. When a follow-up chest roentgenogram was ordered, physicians indicated their reason for ordering the test, the likelihood that the roentgenogram would show changes, and expected alterations in therapy. After the roentgenogram was obtained, physicians described the help provided by the roentgenogram and what changes in therapy were performed. Using receiver operating characteristic curves, we have shown that physicians have difficulty in predicting which roentgenograms will show important changes. Unexpected findings are frequent (25.4%) and highly valued by the physician. Fifty-seven percent of these roentgenograms had a definite or possible influence on patient treatment. Further studies are indicated to define when follow-up chest roentgenograms are likely to be of benefit.
We performed a prospective, blinded, controlled study to test the hypothesis that supine cross-table lateral chest roentgenograms might have an advantage over conventional lateral chest roentgenograms for the detection of pericardial effusion using the epicardial fat stripe sign. In comparison with echocardiography as the gold standard, we found that supine cross-table lateral chest roentgenograms had greater sensitivity (51%) for pericardial effusions than conventional lateral chest roentgenograms (sensitivity, 31%). Specificity was essentially the same for both techniques. A large pericardial effusion was more readily detected by supine cross-table lateral chest roentgenograms (86%) than by the conventional lateral chest roentgenograms (36%). We conclude that a supine cross-table lateral chest roentgenogram should be included in the evaluation of patients with suspected pericardial effusion or in patients in whom a large cardiac silhouette is detected on a standard chest roentgenogram.
Chest roentgenograms were obtained in 90 episodes of acute asthma in adults coming to an emergency room. Of these 90 roentgenograms, 50 (55 percent) were interpreted as normal, 33 (37 percent) showed hyperinflation, and 6 (7 percent) showed minimal interstitial abnormalities unchanged from previous roentgenograms. One (1 percent) showed a new alveolar infiltrate in a patient with allergic aspergillosis. There was no significant correlation between chest roentgenogram interpretation and hospitalization. Our data show that the incidence of specific abnormalities on chest roentgenogram in adults with uncomplicated acute asthma is low and suggests that the information obtained from the roentgenogram is rarely helpful to outpatient management. Chest roentgenograms probably are indicated only when there is clinical evidence of pneumonia, a complication of asthma, or a pulmonary disorder that mimics asthma.
Plain chest roentgenograms may be normal or show nonspecific abnormalities during the frequent febrile episodes that occur in patients after bone marrow transplantation. In this group, ultrafast 10-mm and 3-mm high-resolution CT scans were prospectively performed in 33 patients to determine if useful information was provided that either changed the patient's clinical management or added confidence to the clinical diagnosis. The 36 symptomatic episodes that occurred in 33 patients included fever in 20 episodes and fever combined with cough, dyspnea, chest pain, or rales in 16. Fourteen chest roentgenograms were interpreted as normal, and 22 were interpreted as demonstrating nonspecific changes; however, none of the roentgenograms was considered helpful in that they did not provide sufficient information for further management. In 2 of 14 episodes in patients with normal chest roentgenograms and in 9 of 22 episodes in patients with nonspecific chest roentgenograms, CT scanning resulted in a change in clinical management that included performing bronchoscopy, increasing or changing antibiotic coverage, starting white blood cell transfusions, requesting surgical biopsy, or a combination of these. In 1 of 14 episodes in patients with normal chest roentgenograms and in 8 of 22 episodes in patients with nonspecific roentgenograms, CT added confidence to the diagnosis. In the remaining 16 episodes, CT scans provided no additional information. We conclude that in many instances, noncontrast ultrafast chest CT scans can provide information that may either change a patient's clinical management or more clearly establish the extent of pulmonary disease.
To evaluate the usefulness of lateral neck roentgenograms when laryngotracheobronchitis (LTB) is the suggested diagnosis, three pediatric radiologists were asked to examine a series of lateral neck roentgenograms of subjects with LTB and controls. In six of the group with LTB, the roentgenograms were unreadable. Given adequate roentgenograms, the radiologists diagnosed or excluded LTB with a high degree of accuracy (sensitivity, 93%; specificity, 92%). However, their predictions of severity based on the roentgenograms showed a poor correlation with measures of clinical severity. The clinical severity of those with unreadable roentgenograms was significantly greater.
OBJECTIVE: To determine whether fecal retention in encopretic children can be assessed objectively using the plain abdominal roentgenogram and whether roentgenographic evidence of fecal retention is associated with clinical findings on presentation in encopretic children. DESIGN: Retrospective case studies. SETTING: Two pediatric incontinence clinics. PARTICIPANTS: Sixty children (72% male), aged 4 to 18 years (mean, 8 years), who met Diagnostic and Statistical Manual of Mental Disorders, Revised Third Edition criteria for the diagnosis of encopresis. All had a plain abdominal roentgenogram obtained on presentation. INTERVENTIONS: None. RESULTS: Using a systematic assessment tool with good interrater reliability (kappa = 0.65), 78% (47) of the children had fecal retention by roentgenographic criteria on presentation, while 22% (13) did not. Retentive encopretic children were less likely to have a history of difficult toilet training (P = .018) than nonretentive encopretic children. There was no association between fecal retention and several clinical factors, including historical features commonly attributed to fecal retention. Retentive encopretic children were no more likely to have a palpable abdominal mass than nonretentive encopretic children, but they were more likely to have excessive stool on rectal examination (P = .015). Using the plain abdominal roentgenogram as the gold standard, the rectal examination showed a positive predictive value of 84.8% and a negative predictive value of 50% in assessing fecal retention. CONCLUSIONS: Fecal retention in encopretic children can be assessed objectively from a plain abdominal roentgenogram. Most, but not all, encopretic children present with fecal retention. A positive rectal examination is strongly predictive of fecal retention, in which case a roentgenogram is not necessary to make that diagnosis. A negative rectal examination may not rule out fecal retention, in which case an abdominal roentgenogram may be useful to make that diagnosis.
Forty lumbar pedicles and pedicle screws in four cadavers were used to identify the anterior and posterior portions of the lumbar pedicle cortex by roentgenograms in order to evaluate the penetration of the pedicle cortex by pedicle screws intraoperatively. Firstly, the transverse pedicle angles were measured on roentgenograms. Three roentgenograms were taken on each pedicle in three different directions: (1). medial to the pedicle axis; (2). pedicle axis; (3). lateral to the pedicle axis. They revealed that the anterior portion of the lateral pedicle cortex was demonstrated by the pedicle lateral outline on the roentgenogram medial to the pedicle axis, and the posterior portion by the pedicle lateral outline on the roentgenogram lateral to the pedicle axis. Wire markers were used to confirm these data. Finally, anterior and/or posterior penetrations on the lateral pedicle cortex in pedicle screw fixation were studied by roentgenograms in these cadavers and showed that anterior penetration of lateral cortex was demonstrated by the view medial to the pedicle axis, and posterior penetration by the view lateral to the pedicle axis. It is concluded that projections medical and lateral to the pedicle axis are necessary to identify lateral screw penetration intraoperatively when X-ray checking is used.
To determine the sensitivity for detecting pelvic pathology and instability, roentgenograms and computed tomographic (CT) scans from 59 patients with pelvic injuries that had been admitted to a Level I trauma center were randomly reviewed by a orthopedic surgeon blinded to the study. Normal control roentgenograms and CT scans were included to decrease observer bias. The anteroposterior (AP) roentgenogram detected 66% of all pelvic injuries, 78% of those involving the anterior ring, and 53% of those involving the posterior pelvic ring. The trauma CT scan, 10-mm axial images of the abdomen and pelvis, detected 86% of all pelvic injuries, and 78% of anterior ring and 93% of posterior ring injuries. The sensitivity for detecting pelvic instability from one plain film AP pelvis roentgenogram taken in a trauma room setting was 74%. Inlet and outlet views were 75% sensitive. Trauma CT scans were 93% sensitive and high-definition pelvic CT scans (5-mm pelvic cuts) yielded 100% sensitivity. The mechanism of injury could be ascertained with 73% sensitivity by plain films and with 79% sensitivity by inlet and outlet views; trauma CT scans were 96% and high-definition pelvic CT scans were 100% sensitive. When combined, the AP pelvis roentgenograms and trauma CT scans identified 96% of the injured structures and were 100% sensitive in determining injury force patterns and instability. The data suggested that a good quality AP pelvis roentgenogram in conjunction with a complete trauma CT scan of the abdomen/pelvis should identify both the injury mechanism and pelvic instability with a high degree of sensitivity.
This prospective study evaluated the relative value of lumbar roentgenograms, metrizamide myelography, and discography in identifying structural sources for chronic low-back syndrome. One hundred and eight patients with chronic low-back syndrome were evaluated. Patients had not previously had pathology identified which could explain their pain. On discography, 83 patients (78%) had their pain reproduced at least one abnormal level, identifying a structural component to their pain. Only 22 patients (21%) had all levels of pathology identified by roentgenograms and an additional 17 (16%) had pathology appropriately identified by a combination of myelograms and roentgenograms. Using roentgenograms, myelography, and discography, organic pathology was identified which could explain the patient's symptoms in 100 of 108 patients (93%). Based on this study, we think discography is an important diagnostic tool for use in evaluating patients with chronic low-back syndrome. Discography is essential to adequately identify abnormal levels in patients being considered for fusions. Roentgenograms and myelograms are inadequate evaluation in this chronic pain group in that lack of organic pathology cannot be assumed in the presence of normal roentgenograms and myelograms.
The changes in bone-mineral content in the distal aspect of a cadaveric femur that had been prepared for insertion of the femoral component of a total condylar knee prosthesis were evaluated with visual inspection and computer-processing of roentgenograms and with dual-energy x-ray absorptiometry. Seventeen small slices of bone, each three millimeters wide, were removed so that, finally, 89 per cent of the bone was lost from the distal femoral metaphysis. Standardized lateral roentgenograms of the specimen were made with use of a reference step-wedge of hydroxyapatite, and dual-energy x-ray absorptiometry studies were performed with the x-ray beam tangential to the interface. The roentgenograms were digitized and the bone mineral was measured with use of computer analysis. Dual-energy x-ray absorptiometry was performed with and without the femoral prosthesis in place, in order to determine the effect of the metallic prosthesis on the accuracy of the measurement. A bone loss of 25 per cent or more was identified visually by all five of the readers 100 per cent of the time; losses of 20 to 24 per cent, 15 to 19 per cent, 10 to 14 per cent, and 3 to 9 per cent were correctly identified 92, 75, 66, and 59 per cent of the time, respectively. The measurements of bone-mineral content that were obtained from the digitized roentgenograms were linearly correlated with the actual bone-mineral content (the ash content) (r = 0.97, p < 0.001) and were three times more accurate than the visual readings. The determinations of bone-mineral content with dual-energy x-ray absorptiometry correlated highly with the ash content (r = 1.00, p < 0.001) and were seven times more accurate than the visual readings. There was only a 4 per cent difference between the measurements with dual-energy x-ray absorptiometry made with the prosthesis in place and those made without it in place (p < 0.01). Dual-energy x-ray absorptiometry was the most accurate of the three methods and could detect the smallest experimentally created loss; computer-processing and visual-processing of roentgenograms detected losses of 8 per cent or more and 25 per cent or more, respectively. Dual-energy x-ray absorptiometry and computer-processing of the roentgenograms quantified the bone loss, while visual-processing could detect only the presence or absence of bone loss.(ABSTRACT TRUNCATED AT 400 WORDS)
Eleven clinical criteria have been proposed to limit use of lumbosacral spine roentgenograms in patients with acute low-back pain who are at risk for vertebral cancer, osteomyelitis, acute fracture, or herniated disk. We retrospectively applied the criteria to 471 patients with acute low-back pain in three teaching hospital walk-in clinics. Roentgenograms were obtained at the initial visit in 99 patients (21.1%); the number would have increased to 217 (46.1%) if the criteria had been used. The following four patient characteristics were associated with actual roentgenogram use: older age, longer duration of symptoms, reflex asymmetry, and point vertebral tenderness. Adoption of the 11 criteria studied herein may inadvertently increase roentgenogram use, thereby raising health care costs and exposing more patients to gonadal irradiation. The standard of practice in these three clinics seemed to entail use of less broad roentgenogram selection criteria. Other published guidelines for roentgenograms emphasize clinical follow-up, reserving further evaluation for patients who fail to improve after a trial of bed rest and analgesics.
A new Hokkaido University picture archiving and communication system (HU-PACS) has been in clinical use in the outpatient clinic at HU Hospital. To evaluate the quality of the cathode-ray tube (CRT) monitor images, we compared the detectability of line shadows in the chest roentgenogram images on the CRT monitor with those on the computed radiography (CR) film. We randomized chest roentgenograms from 20 patients who were admitted to the outpatient clinic with pulmonary disease. Two physicians, whose speciality is chest roentgenogram diagnosis, checked whether they could recognize a horizontal fissure line (hairline) on the posteroanterior view and a minor fissure line and major fissure lines on the lateral view. Only 30% of hairlines were recognized on CRT monitor as compared with 65% on CR film. On the lateral view, only 68% of major fissures and 53% of minor fissures on CRT monitor were recognized as compared with 89% and 79%, respective on CR film. Furthermore, it was somewhat difficult to follow entire lines on some of the CRT monitor images. Clinically, the greatest advantage of the PACS is immediate availability of images, including chest roentgenogram, chest computed tomography (CT) and magnetic resonance imaging (MRI). PACS is also convenient for consulting colleagues in other departments. Unfortunately, the quality of the image on the CRT monitor is not yet good enough to visualize line shadows and small solitary lesions on the chest roentgenogram image. Recent advances in high technology have been so rapid, however, that higher resolution CRT monitors will be available soon.
Fractures of the ankle are one of the most commonly treated injuries by orthopedic surgeons. The adequacy of closed treatment of stable lateral malleolar ankle fractures is frequently assessed by repeated roentgenograms. There are no standards, nor studies, however, that provide guidelines as to the necessity of such roentgenograms. This study was designed to determine the average frequency of follow-up roentgenograms in ankle fractures treated by casting, as well as the clinical impact of these roentgenograms. The clinical radiographic data base of a university hospital was reviewed to identify all ankle fractures treated between January 1, 1992 and June 30, 1993. A total of 82 patients satisfied the study criteria of having sustained a stable ankle fracture that was treated by closed means, with sufficient clinical and radiographic follow-up to assess healing of the fracture. All patients healed their fractures at an average of 8.4 weeks (+/- 3.0 weeks), with weight-bearing initiated at 4.0 weeks (+/- 2.7 weeks). No patients developed radiographic evidence of a talar shift during treatment, and none required surgery for a failure of closed treatment. At no time did any ankle exhibit a significant change in fibular alignment relative to the initial injury films. Each patient had an average of 4.5 (+/- 2.0) radiographic studies performed throughout their treatment. This study indicates that secondary displacement of either the talus or fibula in a stable ankle fracture is very unusual. In conjunction with the generally excellent outcome for such fractures, this suggests that frequent roentgenograms are not justified on clinical grounds.(ABSTRACT TRUNCATED AT 250 WORDS)
One hundred thirty-six charts of preoperative patients over the age of 59 years were reviewed to determine whether clinical criteria alone are sufficient to identify patients who would not benefit from preoperative chest roentgenograms. Thirty-four percent of the patients without risk factors and 62% of those in the high-risk group were found to have significant abnormalities on chest roentgenograms (P less than 0.05). Postoperative complications occurred in 20% of patients in the high-risk group compared to 11% complication-rate in patients without clinical risk factors. The difference is not statistically significant. The prevalence of abnormal preoperative chest roentgenograms among those over the age of 70 years (49%) was not significantly different from the prevalence in those between the ages of 60 and 70 years (59%); however, the incidence of major postoperative complications was significantly higher in the older group (17 v 4%, P less than 0.01). Because of the substantial prevalence of abnormal chest roentgenograms and postoperative complications, it is concluded that in the elderly preoperative patients, in particular those over the age of 70 years, chest roentgenograms should be done on all patients regardless of clinical history.