Assessment of ultrasonic computed tomography in symptomatic breast patients by discriminant analysis

From 95 subjects imaged with both speed of sound and attenuation ultrasonic computed tomography (UCT), quantitative analyses are presented on 40 cases where unequivocal correlating clinical diagnoses are available. Using four attenuation and speed of sound parameters from different regions of interest in the breast, a linear discriminator detects cancer with approximately 90% sensitivity and specificity. Increased confidence in the predictive power of this small study is given by a modern test of predictive power (jackknifing) and by the fact that diagnostic discrimination remains as high as 85% when only two parameters are employed--attenuation and speed of sound in the lesion minus those values in the remaining central mammary tissues. Speed of sound images appear particularly useful in older, fatty breasts where pulse echo ultrasound is particularly lacking. While UCT in the form studied here is not likely to receive wide clinical acceptance in the near future, a combined UCT/pulse echo system might find wide clinical utility if it can be sufficiently convenient and inexpensive.     

Results of a multicenter study of the modified hook-titanium Greenfield filter

Initial efforts to modify the stainless steel Greenfield filter for percutaneous insertion led to development of a titanium Greenfield filter, which could be inserted by use of a 12F carrier. This device functioned well as a filter but had an unacceptable 30% rate of migration, tilting, and penetration. Therefore a titanium Greenfield filter with modified hooks was developed and has been tested in 186 patients at 10 institutions. Successful placement occurred in 181 (97%); placement of the remainder was precluded by unfavorable anatomy. A contraindication to anticoagulation was the most frequent indication for insertion (75%). All but two were inserted percutaneously, predominantly via the right femoral vein (70%). Initial incomplete opening was seen in four patients (2%), which was corrected by guide wire manipulation and asymmetry of the legs in 10 (5.4%). Insertion site hematoma occurred in one patient, and apical penetration of the cava during insertion occurred in a second patient. Both events were without sequelae. Follow-up examinations were performed at 30 days at which time 35 deaths had occurred. Recurrent embolism was suspected in six patients (3%) and two of three deaths were confirmed by autopsy. Filter movement greater than 9 mm was seen in 13 patients, (11%) and increase in base diameter greater than or equal to 5 mm was seen in 17 patients (14%). CT scanning showed evidence of caval penetration in only one patient (0.8%). Insertion site venous thrombosis was seen in 4/46 (8.7%) patients screened. The modified hook titanium Greenfield filter is inserted percutaneously or operatively through a sheath, eliminating concern for misplacement from premature discharge.(ABSTRACT TRUNCATED AT 250 WORDS)     

Production of penile veno-occlusive insufficiency by arterial occlusion in a canine model

Angiographic evaluation of impotent men revealed a frequent association between penile arterial disease and veno-occlusive insufficiency of the corpora cavernosa. In order to evaluate a possible cause-and-effect relationship, we investigated the competence of the cavernosal veno-occlusive mechanism in a canine model at various intervals after onset of cavernosal ischemia. In most dogs, the veno-occlusive mechanism could no longer be activated by papaverine after about 30 minutes of ischemia. If ischemia was relieved shortly thereafter, veno-occlusive competence returned after a further delay of one or two hours. The evidence suggests that veno-occlusive failure is not simply a hemodynamic consequence of loss of arterial inflow, but instead secondary to some ischemic injury. We conclude that arterial insufficiency may be one of the causes of cavernosal veno-occlusive insufficiency in humans.     

Pulsed-spray thrombolysis of arterial and bypass graft occlusions.

Pulsed-spray thrombolysis is accomplished through forceful injection of a spray of highly concentrated urokinase into clot by using catheters with multiple side holes. We previously reported the immediate technical efficacy of the method in eight arterial and 10 bypass graft occlusions. We now describe the clinical efficacy of the method in a second, larger series of 23 native artery occlusions and 25 bypass graft occlusions. Transluminal angioplasty was performed after thrombolysis in 21 of the arteries and 24 of the bypass grafts. Initial thrombolysis was observed in all artery occlusions and all but one bypass graft occlusion with an average time for pulsed-spray lysis of 65 +/- 28 min in native arteries and 93 +/- 38 min in bypass grafts. Recanalization with improvement in symptoms or distal pulses after thrombolysis and angioplasty was achieved in 74% of treated arterial occlusions and 92% of treated graft occlusions. Of the 15 arteries that were recanalized and did not require adjunctive surgery, seven remained patent at 3-28 months follow-up. Nine of 23 recanalized bypass grafts required early adjunctive surgery. Of the nine synthetic and five saphenous vein grafts successfully recanalized and not requiring surgical revision, the mean patency was 4.3 +/- 3.1 months and 3.0 +/- 2.2 months, respectively. Minor complications were seen in 23% of cases. The two major complications (4%) involved one groin hematoma requiring surgery and one episode of gastrointestinal hemorrhage. We conclude that combined pulsed-spray thrombolysis and angioplasty achieve rapid and consistent arterial and graft recanalization with minimal risk. The method offers a favorable alternative to standard thrombolytic therapy of arterial occlusions. In occluded synthetic and vein bypass grafts, the technique is sometimes beneficial, either alone or combined with surgical revision.     

An analysis of serum enzyme changes and clinical biochemical abnormalities of the anemia in Olympic runners

In order to assess the changes in the clinical biochemistry of runner's anemia and its evolution during a prolonged period of high-intensity training, 11 male international class distance runners (mean time for 1 mile 4 min, 2.5 sec) were followed over a 10-month period prior to the 1984 U.S. Olympic Trials. Mean values of hemoglobin, hematocrit, and mean corpuscular hemoglobin (MCH) decreased modestly over the period of study. Means of haptoglobin, iron, and total iron binding capacity (TIBC) remained roughly constant. Percentage of saturation of TIBC by iron (% sat) averaged 30% or less in 5 of 11 runners, suggesting mild iron deficiency. Most measured haptoglobin levels were below normal range throughout the study period. The cause of runner's anemia has been demonstrated to be multifactorial, including disordered iron metabolism, iron deficiency, and hemolysis. Other studies have shown absent bone marrow iron in male athletes, secondary to hematuria, ischemia of the intestinal mucosa with bleeding, and iron losses due to heavy perspiring. Cardiorespiratory fitness, evaluated through repetitive treadmill testing, was not adversely affected in our athletes. Total creatine kinase (CK) increased significantly after a training session, while the MB fraction of CK never exceeded 3%. Total lactate dehydrogenase (LD) also rose after exercise, but the fractions represented by isozymes 1-5 were unaltered; specifically, there was no change in the LD-1/LD-2 ratio. Enzyme elevations were thus derived from skeletal muscle and not from heart.