Imaging of four-corner fusion (SLAC arthrodesis) of the wrist with 64-slice computed tomography.

PURPOSE: To find out whether it is possible to evaluate the healing of wrist arthrodesis, carried out with a metallic spider plate, by means of 64-slice computed tomography (CT). MATERIAL AND METHODS: 18 CT examinations were performed in 12 patients 2 weeks to 37 months following scapholunate advanced collapse (SLAC) arthrodesis fixed with a metallic plate. Ten patients also had plain films of the wrist. Radiation doses were estimated. RESULTS: Plain films were difficult to evaluate due to overprojection of the spider plate. With 64-slice CT, however, it was possible to evaluate the healing process in all patients in spite of metallic artifacts. Radiation doses were low. CONCLUSION: The healing of SLAC arthrodesis of the wrist is difficult to evaluate with conventional radiography due to the metallic plate. By means of 64-slice CT, however, it was possible to "see under" the plate in all 12 patients.

Early chest radiography and CT in the diagnosis, management and outcome of invasive pulmonary aspergillosis.

PURPOSE: We report the chest radiographic and CT findings in 21 immunocompromised patients with invasive pulmonary aspergillosis (IPA) and describe the outcome when the early diagnosis was linked to treatment with liposomal amphotericin B. MATERIAL AND METHODS: Chest radiographs and CT examinations were analyzed retrospectively in 53 consecutive neutropenic patients with suspected early IPA. RESULTS: Twenty-one of 244 patients admitted for chemotherapy of hematologic malignancy fulfilled the definition for IPA - incidence of 8.6%. The incidence of normal and non-specific chest radiographic findings was high (29% and 71%, respectively) during the early stages of IPA. The CT halo sign was seen in 20 of the 21 patients (95%), and occurred within 5 days of neutropenic fever that was unresponsive to antibiotics in 5 patients. Crescent signs or cavitations were seen in 7 patients (33%). Treatment with liposomal amphotericin B was associated with an attributable mortality of 9.5%. Two patients died from IPA having a high fungal burden. CONCLUSION: Early chest CT in neutropenic patients at risk for IPA is an important diagnostic and management tool and should be included in the investigative protocol even when chest radiographs are normal or non-specific.

MR and other imaging methods in the investigation of mycetomas.

PURPOSE: To report features of mycetomas (actino- and eumycetoma infection), which belong to the so-called rare bone infections, as evaluated by MR and other imaging methods and to assess chemotherapy treatment. MATERIAL AND METHODS: Twenty patients (average age 57 years) were diagnosed by different modalities. Analyses of 57 plain films, 31 three-phase bone scans, 28 CT and 35 MR examinations were performed. The MR protocol included T1-weighting without and with contrast, T2-weighted, proton density and fat suppressing sequences. RESULTS: Signs of chronic osteomyelitis were seen in plain films of 10 patients (50%), but the healing process was difficult to assess. Bone scintigraphy was positive in 12 patients (60%). In 14 patients (70%), CT could demonstrate bone lesions, but the healing process was difficult to estimate in 4 patients. MR imaging provided accurate diagnostic information in 15 cases (75%). In 16 patients (80%), small lesions could be identified due to grains, which seemed to differentiate mycetoma from other infections and tumorous lesions. MR examination gave definitive answer about the healing process in 18 cases (90%). CONCLUSION: MR investigation was superior to the other imaging techniques in the evaluation of mycetoma and the assessment of therapy.

Diagnostic radiology in an integrated curriculum: evaluation of student appraisal.

RATIONALE AND OBJECTIVES: This study determined student perceptions of the effectiveness of an integrated radiology curriculum in a 6-year undergraduate medical school program. MATERIALS AND METHODS: Student perceptions of the effectiveness of an integrated radiology curriculum were assessed with a self-administered questionnaire that was developed in house and consisted of Likert-type and open-ended items. The questionnaire was distributed to 1997-1998 and 1998-1999 cohorts of 2nd- to 6th-year medical students. Quantitative data were analyzed by using descriptive statistics. RESULTS: Ninety-nine of 173 students (57% response) returned completed questionnaires. Overall, students perceived integrated radiology teaching as satisfactorily achieved and useful in facilitating learning. Compared with students in the 2nd and final years of undergraduate medical education and training, those in years 3-5 considered integrated radiology teaching to be very effective. Results of the survey suggest future modifications to improve the effectiveness of integrated radiology teaching. CONCLUSION: Radiology can be successfully integrated into modern medical curricula. Student comments indicate the need to structure and organize the integrated teaching better and to introduce it earlier in the medical school curriculum.

Interval cancers and cancers in non-attenders in the Ostergötland Mammographic Screening Programme. Duration between screening and diagnosis, S-phase fraction and distant recurrence.

The study was based on a population mammographic screening programme for women aged 40-74 years. Metastatic potential was analysed in 843 invasive breast cancers with regard to mode of detection and a number of prognostic factors. There was a higher metastatic capacity in clinically detected cases, but multivariate analyses showed that neither the mode of detection (hazard rate ratio of distant recurrence RR = 1.39, 95% CI 0.78-2.46 interval cancers and RR = 1.6, 95% CI 0.76-3.36 non-attenders) nor the duration between screening and diagnosis for true interval cancers (RR = 0.47, 95% CI 0.16-1.35 in tumours detected later than one year after screening) were independent prognostic factors. A correlation was found between metastatic potential and the SPF (RR = 2.94, 95% CI 1.57-5.50 in tumours with a high SPF), the oestrogen receptor status and the tumour stage. In conclusion, interval cancers intrinsically are not different from other breast cancers with equivalent characteristics; the duration between screening and diagnosis in interval cancers was not clearly correlated to the prognosis, but the S-phase fraction was a powerful predictor of prognosis.

Blood pressure and heart rate response during exercise in men and women in the USA and Russia lipid research clinics prevalence study.

Examination of blood pressure (BP) and heart rate (HR) measurements at rest and during exercise in samples of USA and Russian middle-aged men and women show significant differences between countries for both genders. Russian men had higher resting systolic blood pressure (SBP) than USA men but lower SBP at both stages of exercise. Russian women had significantly higher resting SBP than USA women at rest and also during exercise. Russian men and women had significantly lower HR at rest and during exercise than USA men and women. Differences between countries were also noted for mean body weight, height, lipid levels, percentages of smokers and several other variables, and it was postulated that differences in these factors might be responsible in part for differences in SBP and HR during exercise. After adjustment for these variables, differences in SBP during exercise between USA and Russian men remained, but differences between USA and Russian women disappeared. For both genders, differences in HR during exercise remained after adjustment. Mortality analyses in USA and Russian men indicated that stage 2 SBP response during exercise was generally not a significant mortality risk factor after adjustment for age, BMI, TC, smoking and resting SBP. In a similar model, stage 2 HR response during exercise was also a non-significant risk factor in mortality.

MR angiography of abdominal and peripheral arteries. Techniques and clinical applications.

This review article deals with MR angiography (MRA) of abdominal and peripheral arteries. Pulsatile flow, respiratory motion and peristalsis impose difficulties in imaging the vascular structures in the abdomen and the lower extremities. Development of new techniques, such as segmentation of the data acquisition, using specific acquisition windows in relation to a cardiac trigger, magnetization preparation of the tissue and phase-encoding re-ordering or sorting, have reduced the artifacts associated with abdominal and peripheral MRA. Clinical MR investigations of the arteries branching from the abdominal aorta such as the renal and mesenteric arteries and arteries in the lower extremities have revealed that severe stenoses or occlusions can be diagnosed accurately while the grading of less severe stenosis is more difficult. The phase-contrast method has been used to quantify blood flow and study the hemodynamics in abdominal and peripheral vessels. Quantitative flow information can be used to diagnose vascular disease and provides important physiological information. More prospective clinical studies, in which recently developed MRA techniques are compared with conventional angiography, are necessary before conclusive decisions can be made as to whether MRA may replace these methods.

The pregnancy zone protein response during gestation: a metabolic challenge.

Prospective studies of pregnant women were performed to compare individual variations in the plasma concentration of sex hormone binding globulin (SHBG) and pregnancy zone protein (PZP) during pregnancy, and to elucidate the degree of co-variation between these oestrogen sensitive proteins during gestation. The plasma concentration of SHBG manifested continuous increase reaching a 12-fold peak at delivery. The increase of the protease inhibitor PZP paralleled that of SHBG reaching a peak with a 25-fold increase by the beginning of the third trimester. Then it started to decline, while that of SHBG continued to increase. The synthesis of the protease inhibitor may also continue to increase during late gestation but its elimination from the circulation may be accelerated when the syncytiotrophoblastic area in contact with the maternal blood approaches its maximum. The unusually wide individual variation of PZP concentrations in non-pregnant women was confirmed. However, the individual levels increased proportionally during the progress of pregnancy, and we may speak of low, medium and high reactors for PZP. One initial conclusion to be drawn from the present findings is that the value of the plasma PZP concentration can only be interpreted from a pathophysiologic point of view if the patient's baseline level is known.

Quality-adjusted meta-analysis of the hypertension/coronary dilemma.

Primary investigators of randomized drug trials in hypertension were invited to rate quality of such trials. The intention of the survey was to ask if antihypertensive drug therapy reduces incidence of coronary heart disease (CHD) in hypertensive patients. Response was obtained for 7 of the 11 invited investigators, covering 69% of patients and 75% of CHD cases. Principal component analysis was used to construct a quality score based on answers to 12 questions along visual analog scales. The score correlated well with the answer to a global question of overall quality given by the raters. No systematic tendency toward favoring one's own trial could be demonstrated, therefore, all raters have contributed to the rating. The trials with the highest rated quality to answer the research question were Systolic Hypertension in the Elderly Program (SHEP), Australian National Blood Pressure Study, Medical Research Council, Veterans Administration, and European Working Party of Hypertension in the Elderly. The large Heart Detection and Follow-up Program (HDFP) trial was rated at 11th place among the trials with a score of < 40% of the SHEP. The small trials performed in the 1960s were placed at the bottom of the ranking list. Because SHEP is the only trial without diastolic hypertension, results were given with and without SHEP results. When incorporating the quality score into a meta-analysis of CHD outcome, results were dependent on whether SHEP was included or not. For diastolic hypertension only, the effect of therapy was estimated to be about 8% for all higher quality studies, whereas inclusion of the lower quality HDFP changed it to 14%. When isolated systolic hypertension trial was pooled with the others, no major relation to quality rating was observed. A 14% CHD preventive efficacy was established when pooling the three top quality studies. This stayed unchanged until HDFP at rank 11 was included raising this estimate to 16%. Inclusion of the two latest published trials in the elderly, the Medical Research Council trial of treatment of hypertension in older adults and the Swedish Trial in Old Patients with hypertension, did not change this overall estimate of 16% (standard error = 3.8%). It is concluded that if all randomized drug trials in hypertension had the same treatment efficacy, the estimated CHD prevention would be in the range of 15%. Subgroup analyses revealed no relationship to age, but a difference in efficacy was shown depending on whether the trials were performed in the United States or elsewhere. Also, patients at higher risk levels showed better benefit than lower risk patients.

Black-white differences in electrocardiographic left ventricular mass and its association with blood pressure (the ARIC study). Atherosclerosis Risk in Communities.

Black-white differences in the association between antihypertensive therapy, continuous measures of mean arterial and pulse pressures and left ventricular (LV) mass estimated from a multivariable electrocardiographic algorithm were examined in 6,020 men (23% black) and 7,970 women (29% black) participating in the Atherosclerosis Risk in Communities (ARIC) study. Mean arterial and pulse pressures, weight, the percentage of subjects taking antihypertensive medication, and LV mass were higher in black than in white men (98 vs 89 mm Hg, 47 vs 46 mm Hg, 188 vs 187 pounds, 30% vs 17%, and 243 vs 217 g, respectively). Results of similar direction but greater magnitude were observed in black versus white women (mean arterial pressure, 94 vs 85 mm Hg; pulse pressure, 50 vs 47 mm Hg; weight, 180 vs 153 pounds; percent treated, 42% vs 18%; and LV mass, 203 vs 169 g, respectively). In multivariable regression analyses, blacks had higher levels of LV mass, and LV mass increased more sharply with increasing mean arterial pressure in blacks than in whites after adjusting for age, pulse pressure, and weight. At equal mean arterial and pulse pressures, age, and weight, treated blacks had higher LV mass than treated whites. These data indicate that blacks have higher LV mass than whites, and a more pronounced blood pressure-LV mass relation after controlling for other risk factors and treatment status. Given the prognostic importance of LV hypertrophy,

Effects of felodipine versus nifedipine on exercise tolerance in stable angina pectoris.

The effects of single doses of felodipine (5 and 10 mg) and nifedipine (10 and 20 mg) on chronic stable effort angina pectoris were assessed in a placebo-controlled, double-blind, crossover study of 24 patients receiving beta blockers and short-acting nitroglycerin. The effects were measured by repeated bicycle ergometer tests. The total work, and time until 1 mm of ST depression increased significantly by 9 to 31% after both active drugs at both dose levels in comparison with placebo. The differences were not significant between drugs or doses. At rest, blood pressure decreased (10 to 15%) and heart rate increased (5 to 10%) significantly after both active drugs. During exercise at the highest comparable work load, systolic blood pressure decreased significantly (23 to 26%), whereas heart rate was not affected after felodipine and nifedipine compared with placebo. The 2 drugs were well tolerated, and side effects were mild. Therefore, single doses of 5 and 10 mg of felodipine, and 10 and 20 mg of nifedipine have similar antianginal and anti-ischemic properties. However, felodipine has a longer duration of action, which may improve compliance.

Selective salpingography and fluoroscopic transcervical salpingoplasty for diagnosis and treatment of proximal fallopian tube occlusions.

In 25 women with primary or secondary infertility, primary hysterosalpingography (HSG) or laparoscopy with chromopertubation indicated 33 proximal and 2 distal tubal obstructions. Four salpingectomies had been performed earlier. All patients were considered for transcervical catheter salpingoplasty (TCSP) to reconstruct tubal patency. Secondary examination with repeat HSG or selective osteal salpingography confirmed 26 proximal and 3 distal tubal occlusions while 17 tubes were patent. Selective osteal salpingography was performed successfully in 32 of 33 (97%) tubes. Sixteen of 26 (61.5%) proximally occluded tubes were successfully recanalized by coaxial catheter and guidewire technique while two of three distally occluded tubes were reopened by forceful flushing of contrast medium. So far, one ectopic and five intrauterine pregnancies were achieved in ten patients with observation time more than four months. Three patients have had normal deliveries. The favorable results, lack of complications and low costs seem to justify the recommendation to use selective salpingography and fallopian tube recanalization as the first intervention in patients with obstruction of the proximal fallopian tube.

Evaluation of anatomical obstruction by Doppler echocardiography and magnetic resonance imaging in patients with coarctation of the aorta.

OBJECTIVE: To evaluate a new Doppler echocardiographic index of obstruction in patients with native coarctation or recoarctation. PATIENTS: 32 patients (mean age 20, range 3 months--50 years). METHODS: Magnetic resonance imaging (MRI) was used to investigate the descending aorta. The cross sectional area of the obstruction was compared with the area of the abdominal aorta as an index of obstruction (CoA index). Doppler echocardiography was used to record the velocities in the coarctation jet and in the abdominal aorta. According to the continuity equation the ratio of these velocities should equal the ratios of the cross sectional areas. The gradients and diastolic half time of the Doppler curve were calculated. RESULTS: There was a close correlation between the MRI index of obstruction and the Doppler velocity ratio (r = 0.92). The sensitivity and specificity of this ratio in detecting a CoA index equal to or less than 0.25 were better than those obtained with gradients only or the combination of gradients and diastolic half time. CONCLUSION: The new Doppler velocity ratio correlated closely with an anatomical index of obstruction. It was easy to record in most patients and it avoided difficulties about the choice of instantaneous or peak to peak gradients and whether or not to subtract proximal velocities for the calculation of gradients.

Instability and femoral head vitality in fractures of the femoral neck.

Sixteen patients with femoral neck fractures were studied with roentgen-stereophotogrammetric analysis (RSA) and low-field magnetic resonance (MR) imaging in addition to plain roentgenography. In six patients, these results were compared with the results of histopathologic analyses. All fractures were stabilized with two cannulated titanium screws. Evaluation of fracture movement before weight bearing (nine fractures) revealed no or only slight movement (less than 3.4 mm or 4.7 degrees). During weight bearing, two undisplaced fractures were compressed about 5 mm and one 20.3 mm, because of delayed union, which was verified by repeated RSA measurements and MR imaging. The average compression in nine displaced fractures that subsequently healed was 13.3 mm. MR imaging revealed signs of femoral head necrosis in three healed and two unhealed fractures. Segmental or total femoral head necrosis was histologically confirmed in all removed femoral heads, and the fracture areas were shown to be bridged by bone trabeculae to a varying degree. Absence of micromovement six months after fracture implied uncomplicated healing. Fracture stabilization at nine to 12 months postfracture was associated with femoral head necrosis or delayed union in four of six cases. Micromotion after more than one year indicated femoral head necrosis or pseudarthrosis.

Clinical characteristics of patients in studies of left ventricular dysfunction (SOLVD).

The Studies of Left Ventricular Dysfunction (SOLVD) trials were designed to evaluate the effects of enalapril on long-term mortality in patients with severe left ventricular (LV) dysfunction. Patients with LV ejection fractions less than or equal to 0.35 and symptoms of congestive heart failure (CHF) were enrolled in the treatment trial, whereas those with no history of overt CHF and taking no treatment directed for LV dysfunction were enrolled in the prevention trial. The baseline clinical characteristics of SOLVD patients were compared to characterize differences between patients in these 2 separate but concurrent trials. From over 70,000 patients screened with LV dysfunction, 4,228 patients were enrolled in the prevention trial and 2,569 patients in the treatment trial. Ischemic heart disease was the primary cause of LV dysfunction in both prevention (83%) and treatment (71%) trial patients. Prior myocardial infarction was present in 80% of the prevention and 66% of the treatment trial patients (p less than 0.001). In the prevention trial, infarction was recent (less than or equal to 6 months) in 27% patients and remote (greater than 6 months) in 57% patients. Treatment trial patients had proportionately more women (20 vs 13%; p less than 0.001) and non-Caucasians (20 vs 14%; p less than 0.001), as well as the coexisting risk factors of hypertension (42 vs 37%; p less than 0.001) and diabetes (26 vs 15%; p less than 0.001) than did prevention trial patients. Clinical characteristics of patients in both trials were influenced by the gender and race of enrolled patients. Similarly, coronary artery bypass surgery was performed less often in women and non-Caucasians.(ABSTRACT TRUNCATED AT 250 WORDS)

Ultra low field MR imaging of cervical spine involvement in rheumatoid arthritis.

In a study of 30 patients with longstanding rheumatoid arthritis the diagnostic usefulness of ultra low field MR equipment was analyzed in assessing lesions of the craniocervical junction. It was found that at 0.04 T all the examinations were diagnostic and that in combination with plain radiography the diagnostic information obtained was valuable in further planning of the treatment strategies. The neurologic findings were related to the degree and severity of atlantoaxial luxation, either horizontal or vertical, and to the periodontoid pannus formation. The correlation between the degree of cord compression shown with MR imaging and the clinical symptoms, especially long tract symptoms, was poor. The only correlating factor was the duration of the disease.

Ultra-low field MR imaging of hepatic hemangiomas (at 0.02 and 0.04 T).

Twelve patients with cavernous hemangiomas of the liver were studied with computed tomography (CT) and ultra-low field magnetic resonance imaging (MRI). Seven patients were examined at a field strength of 0.02 T and 5 patients at 0.04 T, while 3 patients were studied at both field strengths. On T2-weighted images all hemangiomas had the same characteristic appearance of a homogeneous high signal intensity that has been described at higher field strengths. Signal characteristics of the hemangiomas were the same at 0.02 and 0.04 T, but the higher field strength provided better signal-to-noise (S/N) ratio and hence improved image quality. Homogeneous contrast enhancement was seen in three hemangiomas examined after intravenous administration of gadopentetate dimeglumine. Our results indicate that ultra-low field MRI can be useful in the differential diagnosis of hepatic hemangiomas.